Littérature scientifique sur le sujet « Multiple disease resistance »
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Articles de revues sur le sujet "Multiple disease resistance"
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Drake-Stowe, Katherine, Nicolas Bakaher, Simon Goepfert, Berangere Philippon, Regis Mark, Paul Peterson et Ramsey S. Lewis. « Multiple Disease Resistance Loci Affect Soilborne Disease Resistance in Tobacco (Nicotiana tabacum) ». Phytopathology® 107, no 9 (septembre 2017) : 1055–61. http://dx.doi.org/10.1094/phyto-03-17-0118-r.
Texte intégralRésumé :
Phytophthora nicotianae and Ralstonia solanacearum are two of the most important pathogens affecting tobacco worldwide. Greater insight regarding genetic systems controlling resistance to these two soilborne pathogens, as well as identification of DNA markers associated with genomic regions controlling this resistance, could aid in variety development. An evaluation of 50 historical tobacco lines revealed a high positive correlation between resistances to the two pathogens, preliminarily suggesting that some genomic regions may confer resistance to both pathogens. A quantitative trait loci (QTL) mapping experiment designed to investigate the genetic control of soilborne disease resistance of highly resistant ‘K346’ tobacco identified four QTL significantly associated with resistance to P. nicotianae (explaining 60.0% of the observed phenotypic variation) and three QTL to be associated with R. solanacearum resistance (explaining 50.3% of the observed variation). The two QTL with the largest effect on Phytophthora resistance were also found to be the QTL with the greatest effects on resistance to Ralstonia. This finding partially explains previously observed associations between resistances to these two pathogens among U.S. current cultivars and within breeding populations. Further study is needed to determine whether these relationships are due to the same genes (i.e., pleiotropy) or favorable coupling-phase linkages that have been established over time.
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Steffenson, B. J., et K. P. Smith. « Breeding Barley for Multiple Disease Resistance in the Upper MidwestRegion of the USA ». Czech Journal of Genetics and Plant Breeding 42, No. 3 (21 novembre 2011) : 79–86. http://dx.doi.org/10.17221/3646-cjgpb.
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The Upper Midwest is one of the largest barley production areas in the USA. In this region, diseases can markedly reduce both the yield and quality of the crop. Molecular and classical breeding techniques are being employed to develop cultivars with resistance to five different diseases in the Minnesota barley improvement program. Stem rust and spot blotch have been successfully controlled for many years through the deployment of the major gene Rpg1 and a major effect QTL, respectively. A sequence characterized amplified region (SCAR) marker developed from the sequence of Rpg1 has made marker-assisted selection (MAS) for stem rust resistance highly effective. The major QTL controlling durable adult plant spot blotch resistance was first identified in the Steptoe/Morex population. This QTL was completely suppressed in the Harrington/Morex and Dicktoo/Morex populations, highlighting the importance of genetic background for the expression of resistance. The onset of Fusarium head blight (FHB) in 1993 led to dramatic changes in the focus of the breeding program. Significant resources have been expended to develop populations for mapping resistance QTL and identify closely linked markers for MAS. This is a difficult challenge because FHB resistance is controlled by many QTL with small effects. Sources of resistance to net blotch and Septoria speckled leaf blotch (SSLB) have been identified in a number of barley accessions. These resistances are simply inherited and are being introgressed into elite lines via phenotypic and MAS. Continued progress toward multiple disease resistance will require efficient phenotypic screening, MAS, and utilization of discoveries in barley genomics to manage numerous resistance genes and desirable gene complexes assembled over decades of breeding.
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Wiesner-Hanks, Tyr, et Rebecca Nelson. « Multiple Disease Resistance in Plants ». Annual Review of Phytopathology 54, no 1 (4 août 2016) : 229–52. http://dx.doi.org/10.1146/annurev-phyto-080615-100037.
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Fedak, G., D. Chi, C. Hiebert, T. Fetch, B. McCallum, A. Xue et W. Cao. « Multiple disease resistance in intergeneric hybrids ». Vìsnik Lʹvìvsʹkogo nacìonalʹnogo agrarnogo unìversitetu. Agronomìâ, no 23 (1 septembre 2019) : 173–76. http://dx.doi.org/10.31734/agronomy2019.01.173.
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Nene, Y. L. « Multiple-Disease Resistance in Grain Legumes ». Annual Review of Phytopathology 26, no 1 (septembre 1988) : 203–17. http://dx.doi.org/10.1146/annurev.py.26.090188.001223.
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Morelock, T. E., J. C. Correll et L. P. Brandenberger. « 483 PB 417 BREEDING SPINACH WITH MULTIPLE DISEASE RESISTANCE ». HortScience 29, no 5 (mai 1994) : 500e—500. http://dx.doi.org/10.21273/hortsci.29.5.500e.
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Downy mildew (Blue mold) is probably the most common spinach disease in most parts of the world, and it can be a problem in the mid-South. Frequently, other diseases such as white rust and fusarium cause major crop loss. The Arkansas breeding program was initiated 25 years ago to address white rust and fusarium, as well as other diseases that destroy spinach crops. Since single gene resistance is not available for most spinach diseases, it was necessary to utilize polygenic resistance to develop varieties that are resistant to most of the common spinach diseases that occur in the Arkansas River Valley of Arkansas and Oklahoma. Highly resistant genotypes have been developed by using disease nurseries and field screening, so frequent selections are made based on the reaction to 3-4 diseases.
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Erb, W. Alan, et Randall C. Rowe. « Screening Tomato Seedlings for Multiple Disease Resistance ». Journal of the American Society for Horticultural Science 117, no 4 (juillet 1992) : 622–27. http://dx.doi.org/10.21273/jashs.117.4.622.
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Two procedures for screening tomato (Lycopersicon esculentum Mill.) seedlings for resistance to three pathogens were developed. In one scheme, seeds were sprayed with a spore suspension of Fusarium oxysporum f. sp. radicis-lycopersici Jarvis & Shoemaker (fusarium crown and root rot). Resistant seedlings were root-dipped 2.5 weeks later in a spore suspension of Verticillium dahliae Kleb. (verticillium wilt), and 1 week following the root dip, leaves were rubbed with tobacco mosaic virus. In the other scheme, 2-week-old seedlings were dipped in a spore suspension of F. oxysporum Schlecht f. sp. lycopersici (Sacc.) Snyd. & Hans. races 1 and 2 (fusarium wilt). Resistant seedlings were root-drenched 1.5 weeks later with a suspension of Meloidogyne incognita Kofoid & White (rootknot nematode), and 1 week following, the leaves were rubbed with tobacco mosaic virus. These procedures were effective for disease screening, and their use should reduce the time required for development of two multiple disease-resistant populations. Inbreds from each population could be crossed to produce hybrids resistant to five pathogens.
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Thonhauser, K. E., S. Raveh, M. Thoß et D. J. Penn. « Does multiple paternity influence offspring disease resistance ? » Journal of Evolutionary Biology 29, no 6 (29 mars 2016) : 1142–50. http://dx.doi.org/10.1111/jeb.12854.
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Ogbonnaya, F. C., M. Imtiaz, H. S. Bariana, M. McLean, M. M. Shankar, G. J. Hollaway, R. M. Trethowan, E. S. Lagudah et M. van Ginkel. « Mining synthetic hexaploids for multiple disease resistance to improve bread wheat ». Australian Journal of Agricultural Research 59, no 5 (2008) : 421. http://dx.doi.org/10.1071/ar07227.
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A collection of 253 synthetic hexaploid wheats (SHWs) produced from 192 Aegilops tauschii accessions and 39 elite durum varieties were studied to identify, characterise, and evaluate potentially untapped diversity of disease resistance in wheat. The diseases for which resistance was sought included cereal cyst nematode (CCN), root lesion nematode (RLN), Stagonospora nodorum blotch (SNB), Septoria tritici blotch (STB), and the 3 rusts, leaf rust, stem rust, and stripe rust, all important diseases of bread wheat worldwide, which can severely reduce wheat yield and quality. The SHWs exhibited a wide spectrum of resistance to the 8 pathogens. The frequency of disease-resistant SHWs ranged from 1% for one species of RLN (Pratylenchus neglectus), 3% and 10% for Septoria nodorum leaf and glume blotch, 10% for seedling resistance to yellow leaf spot, 16% for CCN, 21% for the second species of RLN (Pratylenchus thornei), 73% for Septoria tritici blotch, and 15%, 40%, and 24% for leaf rust, stem rust, and stripe rust, respectively. Five SHWs, Aus26860, Aus30258, Aus30294, Aus30301, and Aus30304, exhibited high levels of resistance to CCN, YLP, STB, LR, and SR, while 56 SHWs showed resistance to either 3 or 4 diseases. The genetics of resistance to CCN in some of the SHWs revealed that some of the accessions carry the same CCN gene(s) against pathotype Ha13, while others may carry different resistance gene(s). Additional studies were carried out to understand the relationship between the resistances identified in SHWs and the ones already present in common wheat, in particular the resistance genes Cre1 and Cre3 against CCN. The use of perfect markers associated with Cre1 and Cre3 suggested that some SHWs may carry a new CCN resistance gene(s), which could be deployed in breeding programs to increase the diversity of available resistance. The identification of SHWs with resistance to a range of diseases provides an opportunity to generate genetic knowledge and resistant germplasm to be used in future variety development.
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Jansky, S. H., et D. I. Rouse. « Multiple Disease Resistance in Interspecific Hybrids of Potato ». Plant Disease 87, no 3 (mars 2003) : 266–72. http://dx.doi.org/10.1094/pdis.2003.87.3.266.
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Wild species of Solanum are excellent sources of disease resistance genes that may be incorporated into S. tuberosum through breeding. This study was initiated to determine whether multiple forms of disease resistance could be identified in interspecific Solanum hybrids. Thirty-two clones were evaluated for resistance to soft rot, common scab, black scurf, Verticillium wilt, and early blight. Most of the clones originated from populations that were not initially selected for disease resistance traits. Comparisons with the cultivars Atlantic, Russet Norkotah, and Russet Burbank indicated that all clones were more resistant than at least one cultivar for at least one disease resistance trait. Clone C545, which exhibited improved resistance to soft rot, scab, pitted scab, early dying disease, and early blight, appears to be an especially valuable source of disease resistance. The use of interspecific hybridization at the diploid level, combined with sexual polyploidization to return to the tetraploid level, provides a method to introduce multiple forms of disease resistance into advanced clones.
Thèses sur le sujet "Multiple disease resistance"
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Asea, Godfrey Rox. « Genetic characterization of partial resistance and comparative strategies for improvement of host-resistance to multiple foliar pathogens of maize ». Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1133833939.
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Kosaka, Ayumi. « Studies on postinvasive resistance of Arabidopsis thaliana against multiple fungal pathogens ». Kyoto University, 2019. http://hdl.handle.net/2433/245323.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第22128号
農博第2374号
新制||農||1073(附属図書館)
学位論文||R1||N5236(農学部図書室)
京都大学大学院農学研究科応用生物科学専攻
(主査)教授 髙野 義孝, 教授 田中 千尋, 教授 寺内 良平
学位規則第4条第1項該当
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Van, Eeden C. (Christiaan). « The construction of gene silencing transformation vectors for the introduction of multiple-virus resistance in grapevines ». Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/53764.
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Thesis (MSc)--University of Stellenbosch, 2004.ENGLISH ABSTRACT: Viruses are some of the most important pathogens of grapevines. There are no effective chemical treatments, and no grapevine- or other natural resistance genes have been discovered against grapevine infecting viruses. The primary method of grapevine virus control is prevention by biological indexing and molecular- and serological screening of rootstocks and scions before propagation. Due to the spread of grapevine viruses through insect vectors, and in the case of GRSPaV the absence of serological screening, these methods of virus control are not always effective. In the past several methods, from cross-protection to pathogen derived resistance (PDR), have been applied to induce plant virus resistance, but with inconsistent results. In recent years the application of post-transcriptional gene silencing (PTGS), a naturally occurring plant defense mechanism, to induce targeted virus resistance has achieved great success. The Waterhouse research group has designed plant transformation vectors that facilitate specific virus resistance through PTGS. The primary focus of this study was the production of virus specific transformation vectors for the introduction of grapevine virus resistance. The Waterhouse system has been successfully utilised for the construction of three transformation vectors with the pHannibal vector as backbone. Each vector contains homologous virus coat protein (CP) gene segments, cloned in a complementary conformation upstream and downstream of an intron sequence. The primary vector (pHann-SAScon) contains complementary CP gene segments of both GRSPaV and GLRaV-3 and was designed for the introduction of multiple-virus resistance. For the construction of the primary vector the GRSPaV CP gene was isolated from RSP infected grapevines. A clone of the GLRaV-3 CP gene was acquired. The second vector (pHann- LR3CPsas) contains complementary CP gene segments of GLRaV-3. The third vector (pHann-LR2CPsas) contains complementary CP gene segments of GLRaV-2. The cassette containing the complementary CP gene segments of both GRSPaV and GLRaV-3 was cloned into pART27 (pART27-HSAScon), and used to transform N tabacum cv. Petit Havana (SRI), through A. tumefaciens mediated transformation. Unfortunately potential transformants failed to regenerate on rooting media; hence no molecular tests were performed to confirm transformation. Once successful transformants are generated, infection with a recombinant virus vector (consisting of PYX, the GFP gene as screenable marker and the complementary CP gene segments of both GRSPaV and GLRaV-3) will be used to test for the efficacy of the vectors to induce resistance. A secondary aim was added to this project when a need was identified within the South African viticulture industry for GRSPaV specific antibodies to be used in serological screening. To facilitate future serological detection of GRSPaV, the CP gene was isolated and expressed with a bacterial expression system (pETI4b) within the E. coli BL2I(DE3)pLysS cell line. The expressed protein will be used to generate GRSPaV CP specific antibodies.
AFRIKAANSE OPSOMMING: Virusse is van die belangrikste patogene by wingerd. Daar bestaan geen effektiewe chemiese beheer nie, en geen wingerd- of ander natuurlike weerstandsgene teen wingerdvirusse is al ontdek nie. Die primêre metode van beheer t.o.v. wingerdvirusse is voorkoming deur biologiese indeksering, en molekulêre- en serologiese toetsing van onderstokke en entlote voor verspreiding. As gevolg van die verspreiding van wingerdvirusse deur insekvektore, en in die geval van GRSPa V die tekort aan serologiese toetsing, is dié metodes van virusbeheer nie altyd effektief nie. In die verlede is metodes soos kruis-beskerming en patogeen-afgeleide weerstand (PDR) gebruik om virusweerstand te induseer, maar met inkonsekwente resultate. In onlangse jare is post-transkripsionele geenonderdrukking (PTGS), 'n natuurlike plantbeskermingsmeganisme, met groot sukses toegepas om geteikende virusweerstand te induseer. Die Waterhouse-navorsingsgroep het planttransformasievektore ontwerp wat spesifieke virusweerstand induseer d.m.v. PTGS. Die vervaardiging van virus spesifieke tranformasievektore vir die indusering van wingerdvirusweerstand was die primêre doelwit van hierdie studie. Die Waterhouse-sisteem was gebruik vir die konstruksie van drie transformasievektore, met die pHannibal vektor as basis. Elke vektor bevat homoloë virus kapsiedproteïen (CP) geensegmente, gekloneer in 'n komplementêre vorm stroom-op en stroom-af van 'n intronvolgorde. Die primêre vektor (pHann-SAScon) bevat komplementêre CP geensegmente van beide GRSPaV en GLRaV-3, en was ontwerp vir die indusering van veelvoudige-virusweerstand. Die CP-geen van GRSPa V was vanuit RSP-geïnfekteerde wingerd geïsoleer, vir die konstruksie van die primêre vektor. 'n Kloon van die GLRa V-3 CP-geen was verkry. Die tweede vektor (pHann-LR3CPsas) bevat komplementêre CP geensegmente van GLRaV-3. Die derde vektor (pHann-LR2CPsas) bevat komplementêre CP geensegmente van GLRa V-2. Die kasset bestaande uit die komplementêre CP geensegmente van beide GRSPaV en GLRaV-3, was gekloneer in pART27 (pART27-HSAScon), en gebruik om N tabacum cv. Petit Havana (SRI) te transformeer d.m.v. A. tumefaciens bemiddelde transformasie. Ongelukkig het potensiële transformante nie geregenereer op bewortelingsmedia nie; gevolglik was geen molekulêre toetse gedoen om transformasie te bevestig nie. Na suksesvolle transformante gegenereer is, sal infeksie met 'n rekombinante-virusvektor (bestaande uit PYX, die GFP geen as waarneembare merker en die komplementêre CP geensegmente van beide GRSPa V en GLRa V-3) gebruik word om die effektiwiteit van die vektore as weerstandsinduseerders te toets. 'n Sekondêre doelwit is by die projek gevoeg toe 'n behoefte aan GRSPaV spesifieke teenliggame binne die Suid-Afrikaanse wynbedryf geïdentifiseer is, vir gebruik in serologiese toetsing. Om toekomstige serologiese toetsing van GRSPa V te bemiddel, was die CP-geen geïsoleer en in 'n bakteriële uitdrukkingsisteem (PETI4b) uitgedruk, in die E. coli BL21(DE3)pLysS sellyn. Die uitgedrukte proteïne sal gebruik word vir die vervaardiging van GRSPa V CP spesifieke antiliggame.
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Pierson, Frank William. « The roles of multiple infectious agents in the predisposition of turkeys to colibacillosis ». Diss., Virginia Tech, 1993. http://hdl.handle.net/10919/29318.
Texte intégralRésumé :
Colibacillosis is considered one of the more costly diseases encountered in the production of market turkeys. It is responsible for a significant amount of mortality in birds between the ages of 6-12 weeks.
Research conducted over the past 5 years has shown that within the Shenandoah Valley production area, multiple primary infectious agents are responsible for the predisposition of turkeys to colibacillosis. These agents were first identified as potential contributors through field case studies. They include hemorrhagic enteritis (HE) virus, Newcastle disease virus, and Bordetella avium. Further retrospective serologic studies affirmed the role of these primary agents and uncovered the potential involvement of Mycoplasma meleagridis.
Trials were conducted to determine the reproducibility of some multiple agent interactions under laboratory conditions. It was found that Newcastle disease virus or B. avium infection followed by HE virus and Escherichia coli challenge produced clinical colibacillosis.
It is believed that hemorrhagic enteritis virus is the pivotal agent in this process of predisposition. Almost all turkeys are vaccinated for hemorrhagic enteritis in the field. The virulent strains of the virus are known to be immunosuppressive. It is suspected that the vaccine strains are mildly so. Infection with HE vaccine virus was shown to cause an increase in CT8+ cells in peripheral blood. These cells are believed to be suppressor T-cells and may account for the reputed immunosuppressive effects of the virus.
Thus, interactions of multiple infectious agents including Newcastle disease virus, B. avium, M. meleagridis, and HE virus appear to be involved in the predisposition of turkeys to secondary E. coli infections.Ph. D.
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Bassil, Fares. « Multiple system atrophy : a translational approach Characterization of the insulin/IGF-1 signaling pathway ». Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0131/document.
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Ce travail porte sur des approches translationnelles dans les synucléinopathies notamment l’atrophie multisystématisée (AMS). Au-delà de leur rôle dans la régulation du glucose, l’insulin et l’insulin like growth factor-1 (IGF-1) ont des propriétés neurotrophiques. Des études ont montrées que la signalisation de l’insuline/IGF-1 est altérée dans la maladie d'Alzheimer et des données suggèrent l’altération de l’insuline/IGF-1 dans la maladie de Parkinson (MP) et l’AMS. Nous avons mis en évidence une résistance à l’insuline dans les neurones des patients MP et AMS ainsi que dans les oligodendrocytes chez les patients AMS.Mon travail a également consisté à cibler la troncation de l’α-synuclein (α-syn) comme cible thérapeutique. Nous avons démontré dans un modèle murin d’AMS que la diminution de l’α-syn tronquée permettait de réduire l’agrégation d’α-syn et la dégénérescence des neurones dopaminergiques.Enfin, nous avons étudié l’implication dans l’AMS des métalloprotéinases matricielles (MMP), des enzymes impliquées dans remodelage de la matrice, la démyélinisation, la troncation de l’α-syn et la perméabilité de la barrière hémato-encéphalique. Ce travail nous a permis de montrer une augmentation de l’expression et de l’activité de MMPs chez les patients AMS. Nous avons également montré que les cellules gliales sont la source de cette augmentation et que la MMP-2 est retrouvée dans les agrégats des patients AMS.Nous montrons ici de caractéristiques distinctes de l’AMS comme des altérations qui se produisent dans les oligodendrocytes. Nous présentons aussi VX-765 comme un candidat prometteur pour ralentir la progression de la pathologie dans un contexte de synucléinopathieThis work focused on translational approaches in synucleinopathies and more specifically in multiple system atrophy (MSA). Beyond their role in glucose homeostasis, insulin/IGF-1 are neurotrophic factors in the brain. Studies have shown altered insulin/IGF-1 signalling in Alzheimer’s disease and data suggest impaired insulin signaling/IGF-1 in Parkinson's disease (PD) and MSA. The aim of my work was to characterize insulin/IGF-1 signalling in MSA and PD brain tissue. Both groups showed neuronal insulin resistance. Oligodendrocytes in MSA patients were also insulin resistant.In line with the translational approach, we also targeted α-synuclein (α-syn) truncation pharmacologically in MSA transgenic mice, which led to reduced α-syn aggregation and the protection of dopaminergic neurons.We also assessed the activity and distribution of matrix metalloproteinases (MMPs) in the brain of MSA patients compared to healthy controls. MMPs are involved in the remodelling of the extracellular matrix, demyelination, α-syn truncation and blood brain barrier permeability. We showed altered expression and activity of MMPs in two distinct structures in MSA brains. We were also able to show that glial cells were the source of increased MMPs and show a unique expression of MMPs in α-syn aggregates of MSA patients compared to PD, evidence that might hint at a mechanism that is differently altered between PD and MSA.We here show distinct pathological features of MSA such as key alterations occurring in oligodendrocytes, further supporting MSA as a primary oligodendrogliopathy. We also present VX-765 as a candidate drug for disease modification in synucleinopathies
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Baring, Michael Robert. « Selection of a multiple disease resistant runner-type peanut ». Texas A&M University, 2003. http://hdl.handle.net/1969.1/5748.
Texte intégralRésumé :
Four F2:4 populations of peanut (Arachis hypogaea L.) resulting from the complex
cross Tamrun 96 X Tx901639-3 X Sun Oleic 95R were grown in three disease nurseries
over a 2 year period. Three separate selection techniques were applied to determine
which technique would provide the most effective method for selecting a multiple
disease resistant, runner-type peanut. Technique I involved selection at a tomato spotted
wilt virus nursery during the first cycle of selection and transferring the selections to a
Sclerotinia minor (Jagger) nursery for a second cycle of selection in year two.
Technique II was the reciprocal of Technique I. Technique III involved selection of the
populations at a multiple disease nursery for two consecutive years. Selections were
based on disease ratings, growth habits, pod and seed characteristics, and oleic/linoleic
acid ratios. Disease ratings were scored as percentage infection on a scale of 0 (0% plot
infected) to 10 (100% plot infected). Disease severity was also rated on a scale of 1
(symptoms noted, but no yield effects) to 10 (plant death, no yield). There were two
final selections for each population using each selection technique that were yield tested
over a 2 year period to determine which technique was superior. The yield tests were
conducted using completely randomized block design at all three disease nurseries with an additional disease-free site included. Data for disease ratings, yield, grade, and value
per hectare were combined within locations across years. All three selection techniques
provided lines with more disease resistance than the parents; however, there was no
difference detected between the effectiveness of the three techniques in terms of disease
resistance, yield, grade, or value per hectare.
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GIUDICE, GAETANO. « NEW PLANT BREEDING TECHNIQUES AND PRIMING AS A MULTIPLE LEVEL STRATEGY FOR THE CONTROL OF DOWNY MILDEW INFECTION IN GRAPEVINE ». Doctoral thesis, Università degli Studi di Milano, 2022. http://hdl.handle.net/2434/924372.
Texte intégralRésumé :
La presente tesi riguarda tre approcci complementari per un controllo più sostenibile del patogeno Plasmopara viticola: cisgenesi, RNAi e priming di difesa delle piante. Nel primo capitolo viene presentata una breve introduzione generale, toccando i principali aspetti relativi alla viticoltura in Europa, alle caratteristiche della malattia, alle nuove strategie biotecnologiche e al priming nella difesa delle piante. Nel secondo capitolo viene presentata una review che descrive in dettaglio i più recenti approcci biotecnologici per la protezione delle colture, tra cui la cisgenesi, l'editing del genoma, l'RNAi e l'epigenetica. Nel terzo capitolo sono riportate le attività relative alla cisgenesi per l’introduzione della resistenza alla peronospora nella vite, lo studio si è concentrato inizialmente sull'induzione dell'embriogenesi somatica in germoplasma d'élite, ottimizzando la coltivazione dei tessuti floreali per la generazione di calli embriogenici. I geni di resistenza TNL2a e TNL2b appartenenti al locus RPV3-1, che conferiscono resistenza a Plasmopara viticola, sono stati quindi selezionati per lo sviluppo di varietà cisgeniche, con la costruzione di un vettore cisgenico che ospita questi due geni. Viene quindi descritta la trasformazione dei calli embriogenici con i ceppi ingegnerizzati di Agrobacterium tumefaciens e le future attività per la rigenerazione di piante cisgeniche trasformate.
Nel quarto e nel quinto capitolo vengono presentati due articoli che affrontano diversi aspetti legati allo sfruttamento del sistema immunitario delle piante: il primo studio mira a chiarire gli effetti del priming indotto da micorrize sul bilancio tra crescita e difesa nella vite mentre il secondo studio si concentra sull'utilizzo di protocolli di protezione alternativi per il controllo della peronospora in un vigneto commerciale. In particolare, nel quarto capitolo “Mycorrhizal symbiosis balances rootstock-mediated growth-defence tradeoffs”, sono stati valutati i potenziali benefici di un inoculo formato da due specie di micorrize arbuscolari, con o senza aggiunta di monosaccaridi, su giovani barbatelle innestate sui portainnesti 1103P e SO4. L'influenza dei diversi trattamenti è stata valutata combinando l'analisi delle caratteristiche agronomiche con tecniche biochimiche e molecolari. I risultati hanno mostrato che, nonostante il comportamento opposto dei due portainnesti selezionati, nei campioni trattati con le micorrize l'intero microbioma della radice è attivamente coinvolto nel bilanciamento dei costi/benefici tra crescita e difesa.
Infine, nel quinto capitolo, viene presentato l’articolo "Novel Sustainable Strategy to control Plasmopara viticola in grapevine, unveil new insights on priming responses and artropods ecology". Lo studio affronta la riduzione del consumo di fungicidi in viticoltura e dei rischi associati attraverso lo sfruttamento di protocolli alternativi per il controllo della peronospora nella vite confrontandoli con un protocollo di protezione standard adottato da una cantina commerciale. Nel primo protocollo sono stati utilizzati solo induttori di resistenza, mentre il secondo e il terzo protocollo hanno seguito il protocollo standard ma sostituendo i fosfonati con anidride fosforica ed estratto di Ecklonia maxima. I risultati hanno mostrato che all'invaiatura l'incidenza e la gravità della peronospora in tutti i protocolli testati erano significativamente ridotte rispetto ai controlli non trattati sia sulla chioma che sui grappoli. Lo studio ha anche mostrato degli spunti interessanti sulla rimodulazione dell'acido salicilico e dell'acido jasmonico nei due protocolli per la sostituzione dei fosfiti. È interessante notare come gli induttori di resistenza attivando le difese della pianta abbiano indotto anche un breve ritardo nella maturazione dei grappoli, agendo, sul metabolismo dei carboidrati, sulla regolazione dei geni di difesa, sulla risposta sistemica acquisita e sulla disintossicazione dalle specie reattive dell’ossigeno. Nella conclusione sono quindi riassunti i principali risultati di ciascun capitolo, esaminandone gli aspetti più critici, inclusa una breve discussione delle attività preliminari che sono state condotte sull’uso dell’RNAi per il silenziamento di due geni essenziali di Plasmopara viticola.The present thesis relates on three complementary approaches for a more sustainable control of Plasmopara viticola: cisgenesis, RNAi and plant defence priming. A brief general introduction is presented in the first chapter, touching the main aspects relative to viticulture in Europe, characteristics of the disease, new biotechnological strategies and priming of plant defence. The second chapter consists of a review article describing with detail the most recent biotechnological approaches for crop protection, including cisgenesis, genome editing, RNAi and epigenetics. In the third chapter the activities concerning cisgenesis for grapevine downy mildew resistance are reported, the study initially focuses on the induction of somatic embryogenesis from elite germplasm, optimising the cultivation of floral tissues for the generation of embryogenic calli. The resistance genes TNL2a and TNL2b belonging to the RPV3-1 locus, which confers resistance to Plasmopara viticola, were then selected for the development of cisgenic varieties, with the construction of a cisgenic vector harbouring those two genes. Finally, the chapter reports on the Agrobacterium tumefaciens transformation of embryogenic calli that are currently cultivated on selective medium, and on the future activities for the regeneration of transformed cisgenic plants. In the fourth and fifth chapters, two papers addressing different aspects related to the exploitation of plant immune system are presented: the first study aimed at clarifying the effects of arbuscular mycorrhiza priming on the grapevine growth-defence trade-off while the second study was focused on the use of alternative protection protocols for the control of downy mildew in a commercial vineyard. Particularly, in the fourth chapter “Mycorrhizal symbiosis balances rootstock-mediated growth-defence tradeoffs”, the potential benefits of an inoculum formed by two arbuscular mycorrhiza fungal species, with or without a monosaccharide addition, were evaluated on young grapevine cuttings grafted onto 1103P and SO4 rootstocks. The influence of the different treatments was assessed by combining the analysis of agronomic features with biochemical and molecular techniques. The results showed that despite the opposite behaviour of the two selected rootstocks, in mycorrhized samples the whole root microbiome is actively involved in the growth-defence trade off balance. Finally in the fifth chapter the submitted paper “Novel sustainable strategies to control Plasmopara viticola in grapevine unveil new insights on priming responses and arthropods ecology” is presented. The study addresses the reduction of fungicide consumption in viticulture and its associated risks by the exploitation of alternative protocols for the control of downy mildew infection in grapevine, compared to a standard winery protection protocol. In the first protocol, only resistance inducers were used, while the second and third protocols followed the standard protocol but substituting phosphonates with phosphorus pentoxide and Ecklonia maxima extract. The results showed that, at véraison, downy mildew incidence and severity were significantly reduced on both canopy and bunches in the plants treated with all tested protocols compared to non-treated controls. The study also revealed interesting insights about the direct effect of protocols for phosphite substitution on the crosstalk between salicylic and jasmonic acid signalling pathways. Interestingly, by priming plant defences, the resistance inducers caused a short delay in bunch ripening, involving changes in carbohydrate metabolism, regulation of defence related genes, systemic acquired resistance and reactive oxygen species detoxification. In the thesis conclusion, the main findings are then summarised for each chapter, by examining the most critical aspects and including a brief discussion on the preliminary activities that were conducted to exploit the RNAi technique for silencing two essential genes of Plasmopara viticola.
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Oprica, Cristina. « Characterisation of antibiotic-resistant Propionibacterium acnes from acne vulgaris and other diseases / ». Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-755-3/.
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Wade, Jeremy James. « The emergence and significance of multiply resistant enterococcus faecium in patients with liver disease ». Thesis, King's College London (University of London), 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265981.
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Lee, Min Jae. « THE DEVELOPMENT OF NOVEL PROTEASOME INHIBITORS FOR THE TREATMENT OF MULTIPLE MYELOMA AND ALZHEIMER’S DISEASE ». UKnowledge, 2019. https://uknowledge.uky.edu/pharmacy_etds/99.
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Over a decade, proteasome inhibitors (PIs), bortezomib, carfilzomib (Cfz) and ixazomib, have contributed to a significant improvement in the overall survival for multiple myeloma (MM) patients. However, the response rate of PI was fairly low, leaving a huge gap in MM patient care. Given this, mechanistic understanding of PI resistance is crucial towards developing new therapeutic strategies for refractory/relapsed MM patients.
In this dissertation work, we found H727 human bronchial carcinoid cells are inherently resistant to Cfz, yet susceptible to other PIs and inhibitors targeting upstream components of the ubiquitin-proteasome system (UPS). It indicated H727 cells may serve as a cell line model for de novo Cfz resistance and remains UPS dependent for survival. To examine the potential link between proteasome catalytic subunit composition and cellular response to Cfz, we altered the composition of proteasome catalytic subunits via interferon-γ treatment or siRNA knockdown in H727 cells. Our results showed alteration in composition of proteasome catalytic subunits results in sensitization of H727 cells to Cfz. It supported that proteasome inhibition by alternative PIs may still be a valid therapeutic strategy for patients with relapsed MM after having received treatment with Cfz. With this in mind, we designed and synthesized a small library of epoxyketone-based PIs by structural modifications at the P1′ site. We observed that a Cfz analog, harboring a hydroxyl substituent at its P1′ position was cytotoxic against cancer cell lines with de novo or acquired resistance to Cfz. These results suggested that peptide epoxyketones incorporating P1′-targeting moieties may have the potential to overcome Cfz resistance mechanisms in cells.
The immunoproteasome (IP), an inducible proteasome variant which is harboring distinct catalytic subunits, LMP2, MECL1 and LMP7 of the proteasome typically expressed in cells of hematopoietic origin, plays a role in immune response and is closely linked to inflammatory diseases. It has been reported that the IP is upregulated in reactive glial cells surrounding amyloid β (Aβ) deposits in brains of Alzheimer’s disease (AD) patients and AD animal models.
To investigate whether the IP is involved in the pathogenesis of AD, we examined the impact of IP inhibition on cognitive function in AD mouse models. We observed that YU102, an epoxyketone peptide targeting the IP catalytic subunit LMP2, improved cognitive dysfunction in AD mice without clearance of Aβ deposition or tau aggregation. Our cell line model study also showed a potential mode of action of YU102 which is suppressing pro-inflammatory cytokine production in microglial cells. It suggested that LMP2 contributes to microglia-mediated inflammatory response. These findings supported that LMP2 may offers a valuable therapeutic target for treatment of Alzheimer’s disease, expanding the therapeutic potential of the LMP2-targeting strategy.
Livres sur le sujet "Multiple disease resistance"
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Stacey, Knobler, et Institute of Medicine (U.S.). Forum on Emerging Infections., dir. The resistance phenomenon in microbes and infectious disease vectors : Implications for human health and strategies for containment : workshop summary. Washington, D.C : National Academies Press, 2003.
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Hopkins, Tanne Janice, dir. Timebomb : The global epidemic of multi-drug-resistant tuberculosis. New York : McGraw-Hill, 2002.
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Border, Peter. Diseases fighting back : The growing resistance of TB and other bacterial diseases to treatment. London : Parliamentary Office of Science and Technology, 1994.
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Parliamentary Office of Science and Technology. Diseases fighting back. London : Parliamentary Office of Science and Technology, 1994.
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H, Gillespie S., dir. Management of multiple drug-resistant infections. Totowa, N.J : Humana Press, 2004.
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File, Thomas. New insights in the treatment of severe infections in the multiple-drug resistant situation : Proceedings of a satellite symposium to the 11th International Congress on Infectious Diseases, Cancun, Mexico, March 5, 2004. Basel, Switzerland : Karger, 2004.
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Fontanesi, Luca, dir. The genetics and genomics of the rabbit. Wallingford : CABI, 2021. http://dx.doi.org/10.1079/9781780643342.0000.
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Abstract The purpose of the book is to present in one location a comprehensive overview of the progress of genetics in the rabbit, with a modern vision that integrates genomics to obtain a complete picture of the state of the art and of the applications in this species, defined according to the multiple uses and multi-faceted places that this species has in applied and fundamental biology. The 18 chapters cover several fields of genetics and genomics: Chapters 1 and 2 present the rabbit within the evolutionary framework, including the systematics, its domestication and an overview of the genetic resources (breeds and lines) that have been developed after domestication. Chapters 3-5 cover the rabbit genome, cytogenetics and genetic maps and immunogenetics in this species. Chapters 6-8 present the genetics and molecular genetics of coat colours, fibre traits and other morphological traits and defects. Chapters 9-13 cover the genetics of complex traits (disease resistance, growth and meat production traits, reproduction traits), reproduction technologies and genetic improvement in the meat rabbits. Chapters 14-18 present the omics vision, the biotech and biomodelling perspectives and applications of the rabbit. This book is addressed to a broad audience, including students, teachers, researchers, veterinarians and rabbit breeders.
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Gillespie, Stephen H. Management of Multiple Drug-Resistant Infections (Infectious Disease). Humana Press, 2004.
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(Editor), Stacey L. Knobler, Stanley M. Lemon (Editor), Marian Najafi (Editor) et Tom Burroughs (Editor), dir. The Resistance Phenomenon in Microbes and Infectious Disease Vectors : Implications for Human Health and Strategies for Containment -- Workshop Summary. National Academies Press, 2003.
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Young, Rick. Hunting the nightmare bacteria. 2017.
Trouver le texte intégralChapitres de livres sur le sujet "Multiple disease resistance"
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Ayliffe, Michael, Ming Luo, Justin Faris et Evans Lagudah. « Disease Resistance ». Dans Wheat Improvement, 341–60. Cham : Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-90673-3_19.
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AbstractWheat plants are infected by diverse pathogens of economic significance. They include biotrophic pathogens like mildews and rusts that require living plant cells to proliferate. By contrast necrotrophic pathogens that cause diseases such as tan spot, Septoria nodurum blotch and spot blotch require dead or dying cells to acquire nutrients. Pioneering studies in the flax plant-flax rust pathosystem led to the ‘gene-for-gene’ hypothesis which posits that a resistance gene product in the host plant recognizes a corresponding pathogen gene product, resulting in disease resistance. In contrast, necrotrophic wheat pathosystems have an ‘inverse gene-for-gene’ system whereby recognition of a necrotrophic fungal product by a dominant host gene product causes disease susceptibility, and the lack of recognition of this pathogen molecule leads to resistance. More than 300 resistance/susceptibility genes have been identified genetically in wheat and of those cloned the majority encode nucleotide binding, leucine rich repeat immune receptors. Other resistance gene types are also present in wheat, in particular adult plant resistance genes. Advances in mutational genomics and the wheat pan-genome are accelerating causative disease resistance/susceptibility gene discovery. This has enabled multiple disease resistance genes to be engineered as a transgenic gene stack for developing more durable disease resistance in wheat.
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Jamaloddin, Mohammed, Anumalla Mahender, C. Guru Gokulan, Chintavaram Balachiranjeevi, A. Maliha, Hitendra Kumar Patel et Jauhar Ali. « Molecular Approaches for Disease Resistance in Rice ». Dans Rice Improvement, 315–78. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-66530-2_10.
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AbstractRice production needs to be sustained in the coming decades, with changing climatic conditions becoming more conducive to the prevalence of disease outbreaks. Major rice diseases collectively cause enormous economic damage and yield instability. Breeding for disease-resistant rice varieties could be one of the best options to counter these disease outbreaks. Disease-screening protocols and newer technologies are essential for effective phenotyping and would aid in gene discovery and function. Understanding the genetics of disease mechanisms and stacking of broad-spectrum disease-resistance genes could lead to faster development of rice varieties with multiple disease resistance. New molecular breeding approaches are discussed for the development of these varieties. The molecular biology of disease resistance is now better understood and could be well manipulated for improved resilience. Transgenic approaches for disease resistance are discussed. Genome-editing tools for the development of disease-resistant rice varieties are thoroughly discussed. The use of bioinformatics tools to speed up the process and to obtain a better understanding of molecular genetics mechanisms of disease resistance is explained.
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Gonzalez-Santamarta, Maria, Grégoire Quinet, Diana Reyes-Garau, Brigitte Sola, Gaël Roué et Manuel S. Rodriguez. « Resistance to the Proteasome Inhibitors : Lessons from Multiple Myeloma and Mantle Cell Lymphoma ». Dans Proteostasis and Disease, 153–74. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-38266-7_6.
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Ndayihanzamaso, Privat, Sheryl Bothma, Diane Mostert, George Mahuku et Altus Viljoen. « An Optimised Greenhouse Protocol for Screening Banana Plants for Fusarium Wilt Resistance ». Dans Efficient Screening Techniques to Identify Mutants with TR4 Resistance in Banana, 65–77. Berlin, Heidelberg : Springer Berlin Heidelberg, 2022. http://dx.doi.org/10.1007/978-3-662-64915-2_5.
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AbstractFusarium wilt, caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense (Foc), is considered one of the most devastating diseases of banana in the world. Effective management of Fusarium wilt is only achieved by planting banana varieties resistant to Foc. Resistant bananas, however, require many years of breeding and field-testing under multiple geographical conditions. Field evaluation is reliable but time consuming and expensive. Small plant screening methods are, therefore, needed to speed up the evaluation of banana varieties for Foc resistance. To this end, a small plant screening method for resistance to banana Fusarium wilt is presented. The method proposes the planting of 2- to 3-month-old banana plants in soil amended with 10 g Foc-colonised millet seeds. Rhizome discoloration is then evaluated to rank the disease resistance response. The optimized millet seed technique could be useful in mass screening of newly developed genotypes for resistance to Foc.
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Santos, Ana Dos, Alan Thompson, Juliette Awad, Michael J. Garlepp et Hilliard Festenstein. « DNA Polymorphism in Multiple Sclerosis, Correlations with Susceptibility and Resistance to the Disease ». Dans Immunobiology of HLA, 444–45. Berlin, Heidelberg : Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-662-39946-0_180.
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Shain, Kenneth H., et William S. Dalton. « The Bone Marrow Microenvironment : Novel Targets to Circumvent Minimal Residual Disease and Drug Resistance in Multiple Myeloma ». Dans Advances in Biology and Therapy of Multiple Myeloma, 141–68. New York, NY : Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4614-4666-8_8.
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Sofkova-Bobcheva, Svetla, Ivelin Pantchev, Ivan Kiryakov, Petar Chavdarov, Yordan Muhovski, Fatma Sarsu et Nasya Tomlekova. « Induced mutagenesis for improvement of bean (Phaseolus vulgaris L.) production in Bulgaria. » Dans Mutation breeding, genetic diversity and crop adaptation to climate change, 178–93. Wallingford : CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0018.
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Abstract Although historically a surplus food producer, Bulgarian agriculture has faced a downturn in recent decades. Local legume cultivars have lost favour with farmers and the canning industry, due to their low productivity in comparison with imported ones. Diseases and abiotic stresses are the most important factors limiting the production of edible legumes, costing farmers hundreds of euros in lost revenue each year. The overall objective of our ongoing bean mutation breeding programme was to enrich the gene pool of Phaseolus vulgaris L. and to develop genotypes resistant to Xanthomonas axonopodis pv. phaseoli (Smith) (Xap) and Pseudomonas savastanoi pv. phaseolicola (Burkh.) (Psp) using EMS. An elite line and common cultivar (an heirloom and a snap bean type) in Bulgaria, were selected as parents and the chemical mutagen EMS was used for generating mutations. In total, 1000 seeds were treated and the two generated M1 populations were grown in the field. All M2 mutant plants (1650 from initial line IP564 and 2420 from initial cultivar 'Mastilen 11b') were grown in field conditions and a number of phenotypic changes were observed on these mutated plants. They were also screened for Xap disease resistance via leaf artificial inoculation under greenhouse conditions. Individual plant selection was performed for the putatively resistant M2 plants. In the M3 generation these lines were screened using artificial inoculation with Xap and Psp pathogens (leaves and pods) under field conditions. Selected M3-M4 lines with confirmed disease resistance were tested for fresh pod quality. Yield tests were started in M4 and M5 generations and, according to their productivity performance, mutants were advanced to the M6/M7 generation for validation. The expression patterns of genes putatively involved in the resistance reactions towards two races of Psp were determined using qRT-PCR for the specific and reference genes. In conclusion, 50 plants with visible morphological changes and/or increased tolerance to the two targeted bacterial diseases were selected. A total of 20 advanced mutant bean lines are currently being evaluated for their competitiveness in multiple sites.
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Morschhauser, Franck, et Pier Luigi Zinzani. « Indolent Lymphomas ». Dans The EBMT/EHA CAR-T Cell Handbook, 83–86. Cham : Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-94353-0_15.
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AbstractIndolent non-Hodgkin lymphoma (iNHL), including follicular (FL) and marginal zone (MZL) lymphoma, now enjoy durable disease control with first-line immunochemotherapy, with a median overall survival (OS) of over 15 years in most series (Kahl and Yang 2016). However, iNHL is still widely considered incurable in most cases, and disease history remains characterized by a relapsing and remitting course, with each remission period shorter than the previous one, and OS and progression-free survival (PFS) decrease with each subsequent line of conventional therapy (Batlevi et al. 2020). Patients with unmet needs include approximately 20% of FL patients who experience disease progression within 24 months (POD24) after initial chemoimmunotherapy (with a 5-year OS of 48% (Casulo et al. 2015)—although it remains unclear how much this worse outcome is driven by misdiagnosed transformed follicular lymphoma (Freeman et al. 2019)) and those who fail multiple regimens (5-year PFS of 23%) (Rivas-Delgado et al. 2019) have double refractory disease (Gopal et al. 2017) or experience relapse after autologous stem cell transplantation (ASCT) (Sesques et al. 2020). Although promising results were obtained with an immunomodulatory regimen combining anti-C20 Moab and lenalidomide (Leonard et al. 2019; Morschhauser et al. 2019), most current approved therapies do not overcome incremental disease resistance, resulting in multiple lines of treatment with cumulative toxicity over a patient’s lifetime. The autologous anti-CD19 chimeric antigen receptor T cell (CAR-T) therapies tisa-cel and axi-cel, which are now approved for patients with relapsed/refractory (r/r) large B cell lymphoma (LBCL), have also been tested in iNHL, with promising results.
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Das, Priyanka, Rajeev N. Bahuguna, Rohit Joshi, Sneh Lata Singla-Pareek et Ashwani Pareek. « In search of mutants for gene discovery and functional genomics for multiple stress tolerance in rice. » Dans Mutation breeding, genetic diversity and crop adaptation to climate change, 444–50. Wallingford : CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0045.
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Abstract Mutation breeding is a commanding tool, which has been adapted to generate altered genetic material to study functional genomics, including understanding the molecular basis of stress tolerance. Hitherto, several rice lines have been generated through mutagenesis and the mutated genes responsible for the 'gain of function' in terms of plant architecture, stress tolerance, disease resistance and grain quality have been characterized. Oryza sativa L. cv. IR64 is a high-yielding rice cultivar but sensitive to abiotic stresses such as acute temperatures, salinity and drought. In this study, a population of rice IR64 mutants was generated using gamma irradiation. The population was then subjected to a preliminary phenotypic screening under abiotic stresses such as heat and salinity at the seedling stage. On the basis of root length, shoot length, fresh weight, dry weight and chlorophyll measurements, we identified eight 'gain-of-function' mutant lines and used them for further biochemical and molecular characterization. Phenotyping results demonstrated that the identified mutant plants have gained the potential to thrive under heat and salinity conditions. This information would be of wide scientific interest and helpful for developing novel cultivars able to maintain yield in saline, hot and dry areas.
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Millar, Michael. « A Capability Perspective on Antibiotic Resistance, Inequality, and Child Development ». Dans Ethics and Drug Resistance : Collective Responsibility for Global Public Health, 225–42. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-27874-8_14.
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Abstract Nussbaum’s capability theory by drawing attention to multiple determinants of wellbeing provides a rich and relevant evaluative space for framing antibiotic resistance. I consider the implications of antibiotic resistance for child development and adult capabilities. There are common risk factors for childhood growth stunting and the spread of infectious diseases in both antibiotic sensitive and resistant forms. The interaction between infectious diseases, antibiotic resistance and growth stunting illustrates a clustering of disadvantage. The control of antibiotic resistance requires wide-ranging cooperative action. Cooperation is predicated on an expectation of equitable access to effective antibiotics. This expectation is confounded by inequality both in access to antibiotics, and in the risk that available antibiotics will be ineffective. Securing child development (and adult capabilities) requires that inequalities both in access to antibiotics and in risk factors for the dissemination and transmission of antibiotic resistance are addressed. Inequality undermines the cooperative activity that is control of infectious diseases and compounds the threat to the securing of capabilities that arises from antibiotic resistance.
Actes de conférences sur le sujet "Multiple disease resistance"
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Song, Seung Yun, Yinan Pei, Steven R. Tippett, Dronacharya Lamichhane, Christopher M. Zallek et Elizabeth T. Hsiao-Wecksler. « Validation of a Wearable Position, Velocity, and Resistance Meter for Assessing Spasticity and Rigidity ». Dans 2018 Design of Medical Devices Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/dmd2018-6906.
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Patients with neuromuscular disorders such as Parkinson’s disease (PD), traumatic brain or spinal cord injury, or multiple sclerosis (MS) can develop different levels of abnormal muscle behavior (hypertonia) such as rigidity and spasticity [1], [2]. Hypertonia can affect different parts of the body such as upper or lower extremities. Symptoms include pain, increased muscle tone, spasms, and decreased functional abilities. Hypertonia can interfere with many activities of daily living, greatly affecting the quality of life in patients and causing anxiety, depression, and social isolation [2].
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Peelukhana, Srikara V., Kranthi K. Kolli, Massoud Leesar, Mohamed Effat, Tarek Helmy, Imran Arif, Eric W. Schneeberger, Paul Succop et Rupak K. Banerjee. « Distinguishing Epicardial and Microvascular Disease Using Combined Functional and Anatomical Endpoints in a Porcine Model ». Dans ASME 2012 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/sbc2012-80464.
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For a better treatment of coronary artery disease in a catheterization lab, detection of the relative contributions of the epicardial stenosis (ES) and concomitant microvascular disease (MVD) is important. To diagnose ES, fractional flow reserve (FFR), the hyperemic stenosis resistance index (hSRv) and to diagnose MVD, hyperemic microvascular resistance index (hMRv) have been tested in cath labs. However, for concurrent assessment of ES and MVD, functional parameter utilizing flow and pressure values, pressure drop coefficient (CDP) and combined functional and anatomical parameter, lesion flow coefficient (LFC) are defined. To test the ability of CDP and LFC to account for ES and MVD, they were correlated with the hSRv and hMRv. We hypothesize that CDP and LFC will have a better combined correlation with hSRv and hMRv. Simultaneous pressure and flow readings were obtained in 11 Yorkshire swine. Single and multiple linear regression analyses were conducted between the FFR, CDP and LFC vs hSRv and hMRv. The correlation coefficient (r) was used to check the strength of correlation. The individual correlation between hSRv and hMRV with CDP (r = 0.90; r = 0.78) and LFC (r = 0.89; r = 0.95) was stronger compared to FFR (r = 0.63; r = 0.32). The combined correlation between hSRv and hMRv with CDP (r = 0.95) and LFC (r = 0.95) increased from the individual correlation. Therefore, we conclude that CDP and LFC can diagnose ES and MVD concurrently and might prove to be improved diagnostic parameters than FFR.
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Araldi, Bianca Barbosa, Victor Hugo Gomes, Bruno Ludvig Vieira, Klesia Adayani Rodrigues, Andressa Gabrieli da Silva, Leticia Scolari, Gabriela Vasconcellos Santana, Jessica Marafiga, Maria Paula Carvalho et Heloise Helena Siqueira. « Effects of multiple sclerosis in pregnant and post-birth : particularities of the disease activity ». Dans XIII Congresso Paulista de Neurologia. Zeppelini Editorial e Comunicação, 2021. http://dx.doi.org/10.5327/1516-3180.704.
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Introduction: Demyelinating diseases are a heterogeneous group of neurological diseases related to autoimmunity whose representative is Multiple Sclerosis (MS). It is characterized by an immune-mediated demyelination of the central nervous system, with a typical outbreak and remission clinic. During pregnancy, a reduction in disease activity was noted due to immunomodulatory effects, and an increase in outbreaks in the puerperium. Thus, our goal is to demonstrate the relationship between pregnancy and MS. Methods: This is a systematic bibliographic review based on searching the SCIELO, PUBMED and UPTODATE databases using the words “Multiple Sclerosis”, “Pregnancy”, “Demyelinating diseases” and “Neurological Disorders”. Discussion: Pregnancy is responsible for numerous changes in the maternal body resulting from hormonal changes with an immunological and neuroprotective effect. Until the beginning of the 20th century, it was considered a risk factor or precipitator of outbreaks in these patients. In 1950, Tillmann et al. questioned him and concluded that pregnancy reduces the risk of outbreaks of the disease and that relapses were more associated with postpartum. The question is still raised by several authors, due to their interest in the search for intricate protective factors in the genesis and cure of the disease. It is believed that immunological changes in pregnancy tend to suppress the maternal immune system preventing fetal rejection, and together with gestational hormones, they are able to make neuronal tissue more resistant to inflammatory aggression and greater capacity for cell repair. In the puerperium, there was an increase in outbreaks of the disease, probably associated with a reduction in hormone levels, the effects of which are lost after the elimination of the fetus. Breastfeeding is not associated with the prevention or risk of new MS outbreaks. The frequency of outbreaks before conception is the only independent predictor of new post-term episodes. There is no consensus regarding the therapeutic approach in these pregnant women. Conclusion: Evidence supports the association between pregnancy, reduced activity of MS and increased activity in the 3 months postpartum, due to the probable loss of neuroprotective effects associated with hormones. Recommendations regarding the use of immunomodulator are suspended before conception (“washout”) until term. New evidence did not associate the use of interferon-β with abortion, cesarean section or low birth weight. There was a benefit of long-term parity with a cumulative effect on the patient’s immunohumor modulation.
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Sheets, Kevin, et Amrinder Nain. « Cell Shape Control and Related Focal Adheshion Dynamics on Aligned Fiber Networks ». Dans ASME 2012 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/sbc2012-80917.
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Cellular elasticity, a measure of a cell’s resistance to changing its shape in response to external stimuli, has been shown in the recent past to be a potential indicator of cell health [1]. A variety of methods including AFM techniques [1, 2], magnetic/optical tweezers [3, 4], and micropillar arrays [6–8] have been used to quantify cellular elasticity to identify cell disease state, including stages of progression in cancerous cells. Since cellular behavior is heavily dependent on the physical nature of the surrounding extracellular matrix (ECM), understanding mechanical cell-substrate interactions may lead to connections between the elasticity of a cell and the cell’s health state [1]. In this study, the STEP (Spinneret-based Tunable Engineered Parameters) technique is used to create suspended nanofibrous polystyrene substrates with tight control on fiber diameter and spacing in single and multiple layers. As cells interact with these various substrates, they take on repeatable configurations and allow the probing of biophysical traits. Specifically, cytoskeletal arrangements provide information on the behavior of the cell nucleus, f-actin stress fibers, and focal adhesions via paxillin staining, which allow for calculation of cellular elasticity.
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MAJEED, Huda Zuheir, Firas Nabeeh JAAFAR, Mohammed Twfeek ABID ALHUSAIN, Shatha Zuheir MAJEED et Nadia Kamil BASHAR. « THE ANTIBACTERIAL EFFECTS OF GREEN TEA EXTRACT ON RESISTANT BACTERIA ISOLATED FROM HUMAN EYE INFECTIONS ». Dans IV.International Scientific Congress of Pure,Appliedand Technological Sciences. Rimar Academy, 2022. http://dx.doi.org/10.47832/minarcongress4-28.
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Ocular infection is a world wide issue especially for public health field which could be a result to its own normal flora due to subjection to external factors (e.g. stress, getting older, hits, surgical operations, systemic diseases and losing commensal flora). Ocular pathogens could be healed by a group of topical antibiotics, but with time, drug resistance had been developed, which more magnified by wrong diagnosis and random use of antibiotics leading to unexpected complications e.g. visual problems, leading to blindness at last . Alternative therapy had been used to treat such infections including plant extracts like Green Tea (Camellia sinensis) . Eye swabs about (50) samples were gathered from people had ocular infections,then biochemical tests diagnosed (30) bacterial isolates. There were (17) isolates (6 isolates of Staphylococcus spp. and 11 isolates were Enterococcus) out of the (30) isolates showed multiple antibiotic resistance to nine antibiotics by disc-diffusion method,there were high complete resistance to Moxifloxacin and Bacitracin, in contrast to Ciprofloxacin and Chloramphenicol. The antibacterial effects of hot water, cold water,Acetone, Ethanol and Methanol Green tea extracts was examined against the (17) multiple antibiotic resistant isolates by agar-well diffusion method using. Only the Ethanol and Methanol green tea extract showed promising results, without any effect of the remaining green tea extracts. Green tea extracts were equal to Ciprofloxacin and Sulphamethoxazole in effectiveness against antibiotic resistant isolates . The (17) isolates were tested for production of biofilm and protease. (12) isolates were biofilm-producer but after subjection to Ethanol Green tea extract changed into non biofilmformer. (13) isolate were protease-producer but after subjection to Ethanol Green tea extract changed into non protease-former. Key words: Eye Swabs, Antibiotic Resistance, Alternative Therapy, Green Tea Extracts, Biofilm and Protease.
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Pangerti, Fitria Diyah Ayu, Pawito Pawito et Hanung Prasetya. « Factors Affecting Adherence to Antiretroviral Therapy : Application of Theory of Planned Behavior in Malang, East Java ». Dans The 7th International Conference on Public Health 2020. Masters Program in Public Health, Universitas Sebelas Maret, 2020. http://dx.doi.org/10.26911/the7thicph.02.53.
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Background: Adherence to antiretroviral (ARV) treatment is known as an important component in achieving the success of an optimal HIV therapy program. Poor adherence to antiretroviral therapy (ART) is associated with less effective viral suppression, which creating permanent treatment resistance. The purpose of this study was to examine factors affecting adherence to ARV therapy. Subjects and Method: A cross-sectional study was conducted in Malang, East Java, from September to October 2019. A sample of 200 PLWH was selected by fixed disease sampling. The dependent variable was adherence to ARV therapy. The independent variables were cues to action, perceived susceptibility, perceived benefit, attitude, and CST service. The data were collected by medical record and questionnaire. The data were analyzed by a multiple linear regression. Results: Adherence to ARV therapy in PLWH increased with strong cues to action (OR= 6.40; 95% CI= 3.13 to 13.12; p<0.001), strong perceived susceptibility (OR= 3.61; 95% CI= 1.82 to 7.13; p<0.001), strong perceived benefit (OR= 4.68; 95% CI= 2.37 to 9.28; p<0.001), and positive attitude (OR= 5.39; 95% CI= 2.69 to 10.83; p<0.001). CST service was associated with adherence to ARV therapy but it was statistically non-significant (OR= 0.63; 95% CI= 0.33 to 1.20; p=0.130). Conclusion: Adherence to ARV therapy in PLWH increases with strong cues to action, strong perceived susceptibility, strong perceived benefit, and positive attitude. CST Keywords: Care, support, and treatment service, people living with HIV/AIDS Correspondence: Fitria Diyah Ayu Pangerti. Masters Program in Public Health, Universitas Sebelas Maret. Jl. Ir. Sutami 36A, Surakarta 57126, Central Java, Indonesia. Email: ayupangerti13@yahoo.com. Mobile: 081332600710. DOI: https://doi.org/10.26911/the7thicph.02.53
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Lobis, Yusuf Bachtiyar, Bhisma Murti et Hanung Prasetya. « Influences of Peer Support Group and Psychosocio- Economic Determinants on Treatment Compliance in Hiv/Aids Patients in Sragen, Central Java ». Dans The 7th International Conference on Public Health 2020. Masters Program in Public Health, Universitas Sebelas Maret, 2020. http://dx.doi.org/10.26911/the7thicph.02.59.
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Background: Adherence to treatment is important to reduce viral replication, improve clinical and immunological conditions, reduce the risk of developing ARV resistance, and reduce the risk of HIV transmission. Peer support is suspected to be one of the factors driving drug intake adherence in patients with chronic disease. This study aimed to examine the influences of peer support and psychosocio-economic determinants on treatment compliance in HIV/AIDS patients. Subjects and Method: This was a case control design study conducted in Sragen, Central Java, Indonesia. A sample of 200 people with HIV/AIDS (PLWH) was selected by fixed disease sampling. The dependent variable was treatment compliance. The independent variables were knowledge toward HIV/AIDS, perceived benefit, perceived belief, perceived threat, perceived susceptibility, perceived seriousness, perceived barrier, attitude, indirect experience, family support, and peer support. The data were obtained from medical record and questionnaire. The data were analyzed by a multiple logistic regression run on Stata 13. Results: Treatment compliance increased with strong peer support (b= 1.34; 95% CI= 0.31 to 2.38; p= 0.011), strong family support (b= 1.09; 95% CI= 0.16 to 2.02; p= 0.021), knowledge toward HIV/AIDS (b= 1.65; 95% CI= 0.67 to 2.64; p= 0.001), high perceived benefit (b= 1.23; 95% CI= 0.28 to 2.18; p= 0.011), perceived belief (b= 2.05; 95% CI= 0.98 to 3.12; p<0.001), and high perceived threat (b= 1.22; 95% CI= 0.30 to 2.13; p= 0.009). Treatment compliance decreased with negative attitude (b= -2.47; 95% CI= -3.58 to -1.37; p <0.001), low perceived susceptibility (b= -1.26; 95% CI= -2.24 to – 0.27; p= 0.012), low perceived seriousness (b= -1.11; 95% CI= -2.06 to -0.16; p=0.021), high perceived barrier (b= -1.76; 95% CI= -2.81 to -0.70; p= 0.001), and indirect experience (b= -1.10; 95% CI= -2.05 to -0.14; p= 0.024). Conclusion: Treatment compliance increases with strong peer support, strong family support, high knowledge toward HIV/AIDS, high perceived benefit, perceived belief, and high perceived threat. Treatment compliances decrease with negative attitude, low perceived susceptibility, low perceived seriousness, high perceived barrier, and indirect experience. Keywords: HIV/AIDS, treatment compliance, peer support, psychosocial economy Correspondence: Yusuf Bachtiyar Lobis. Masters Program in Public Health, Universitas Sebelas Maret. Jl. Ir. Sutami 36A, Surakarta 57126, Central Java. Email: bachtiyar03@gmail.com. Mobile: +628111388841. DOI: https://doi.org/10.26911/the7thicph.02.59
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Johar, Alreem, Najlaa Al-Thani, Sara Al-Hadidi, Elyes Dlissi, Mahmoud Mahoud et Nahla Eltai. « Antibiotic Resistance and Virulence Gene Patterns Associated with Avian Pathogenic Escherichia coli from Broiler Chickens in Qatar ». Dans Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2021. http://dx.doi.org/10.29117/quarfe.2021.0102.
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Introduction: Avian Pathogenic Escherichia coli (APEC) is the contributing agent behind the avian infectious disease colibacillosis, which causes substantial fatalities in poultry industries that significantly impact the economy and food safety. Several virulence genes have been shown to be concomitant with the extra-intestinal survival of APEC. This study investigates the antibiotic resistance patterns and APEC‐associated virulence genes content in Escherichia coli (E. coli) isolated from non‐healthy and healthy broiler chickens from a commercial poultry farm in Qatar. Material and Methods: 158 E. coli strains were isolated from 47 chickens from five different organs (air sac, cloacal, kidney, liver, and trachea). Genomic DNA was extracted from E. coli using the QIAamp Pathogen Mini Kit. Multiplex PCR was executed to detect tsh, iucD, ompT, hlyF, iroN, iss, vat, cvi/cva genes associated with PPEC. Antibiotic susceptibility testing was performed using the standard Kirby-Bauer disk and E-test. Amplified virulence genes detected were sequenced and analyzed. Graph Pad version 8 and PAST software version 4.03 were used for statistical and clustering analysis. The chi-square test was performed on all data to compare the antibiotic resistance and virulence gene patterns between non-healthy and healthy chicken samples Results: 65% of the isolated bacteria were APEC strains containing five or more virulence genes, and 34% were non‐pathogenic E. coli (NPEC) strains. The genes ompT, hlyF, iroN, tsh, vat, iss, cvi/cva, and iucD were significantly prevalent in all APEC strains. E. coli isolates showed 96% resistance to at least one of the 18 antibiotics, with high resistance to ampicillin, cephalothin, ciprofloxacin, tetracycline, and fosfomycin. Conclusions: Our findings indicate high antibiotic resistance prevalence in non-healthy and healthy chicken carcasses. Such resistant E. coli can spread to humans. Hence, special programs are required to monitor the use of antibiotics in chicken production in Qatar.
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Ribeiro, Fernanda Cristina Poscai, et Everton Lopes Rodrigues. « Differentiating clinical examinations of Parkinson’s and parkisonisms ». Dans XIII Congresso Paulista de Neurologia. Zeppelini Editorial e Comunicação, 2021. http://dx.doi.org/10.5327/1516-3180.189.
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Introduction: The main symptoms of Parkinson are: tremors, movement resistance, postural instability and bradykinesia. However, other diseases such as Progressive Supranuclear Paralysis, Multiple System Atrophy and Corticobasal Degeneration have similar symptoms. This similarity generates a difficulty of diagnosis, for example, Corticobasal Degeneration is often diagnosed by autopsy. Objectives: To define the differentiating symptoms of Parkinson and the diseases mentioned and to find clinical tests that could aid in the diagnosis. Methodology: The integrative review utilized Scielo and Pubmed databases and the selected clinical examinations were obtained by the book Exame Clinico - 8° edition. Results: Multiple Systems Atrophy is distinguished from Parkinson by occurrence of cerebelar abnormalities, therefore Romberg Test can evidence modified coordination, which may be indicative of Multiple System Atrophy. Corticobasal Degeneration causes loss of ability to identify things by touch and impaired sensitivity on one side of the body, thereby the verification of stereognosia and the examination of superficial sensitivity are useful. Supranuclear Paralysis Progressive generates difficulty of performing vertical movements, thus the examination of ocular motility is necessary. Conclusion: Only clinical examinations aren’t sufficient to generate an accurate diagnosis and complementary exams are necessary for greater precision. However, knowledge about differentiating clinical examinations helps to generate a line of reasoning and examinations to be requested.
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Arora, Rahul D. « Definition, etiopathogenesis, management and role of flouroquinolone prophylaxis in prevention of spontaneous bacterial peritonitis complicating malignant ascites ». Dans 16th Annual International Conference RGCON. Thieme Medical and Scientific Publishers Private Ltd., 2016. http://dx.doi.org/10.1055/s-0039-1685345.
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Background: Malignancy related ascites encompasses multiple etiologies which include peritoneal carcinomatosis, hepatic synthetic dysfunction due to parenchymal involvement by the tumour, transcoeloemic metastasis and chylous ascites due to lymphatic obstruction. Primary Cancer type, liver metastasis and serum albumin have been listed as independent prognostic markers in malignant ascites. Spontaneous Bacterial Peritonitis is usually seen as a complication of decompensated chronic liver disease due to translocation of bacteria or haematogenous dissemination from a distant focus of infection. The combination of a positive peritoneal fluid culture and an ascitic fluid neutrophil count >250 cells/mm3 and no evidence of intra-abdominal source of infection; or 2) culture negative neutrocytic ascites: the combination of negative peritoneal fluid bacterial culture and neutrophil count >500 cells/mm3, without antibiotics within 7 days with no obvious source of infection are used to define spontaneous bacterialperitonitis. Ciprofloxacin prophylaxis has been proposed as a prophylaxis to reduce the incidence and prevent the recurrence of spontaneous bacterial peritonitis. Materials and Methods: A web search of indexed literature was carried out articles containing information on spontaneous bacterial peritonitis in the setting of malignancy or malignancy related ascites or malignant ascites. Articles that carried relevant information about etiopathogenesis, management and translational research in the context of malignant ascites were also included. Results: A total of 32 articles were analysed and about half of them included in the discussion to answer the research question. Discussion: Inflammatory cytokines released by tumor and immune cells compromise the mesothelial cell layer that lines the peritoneal cavity, exposing the underlying extracellular matrix to which cancer cells readily attach leading to formation of spheroids which imparts resistance to anoikis, apoptosis and chemotherapeutics leading to efficient feed forward progressive cycle of seeding and growth of peritoneal metastasis. Intraperitoneal metastasis can cause peritoneal dysfunction, adhesions and malignant ascites. Epithelial mesenchymal transistion and myofibroblastic transformation occur in the mesothelial cells in response to pathological stimuli. Vascular endothelial growth factor is an important mitogen for endothelial cells and plays an important role in increasing capillary vascular permeability. In preclinical studies systemic administration of VEGF Trap which acts as a decoy receptor for VEGF has shown to decrease the formation of ascites fluid and prevent tumour dissemination. Epithelial ovarian cancer cells have developed various mechanisms to evade immune surveillance like development of surface microvesicles which contain CD 95 ligand leading to apoptosis of immune cells. Higher levels of osteoproteogerin, IL 10 and leptin in the ascitic fluid have been associated with a poor prognosis in malignant ascites. Tethered bowel sign and presence of fluid in the omental bursa on CT have been shown to distinguish between malignant ascites and Cirrhotic ascites with accuracy. Immunological approaches to management of malignant ascites include use of intraperitoneal triamcinolone, interferon, long acting synthetic corticosteroids and the trifoliate antibody catumaxomab. VEGF Inhihibitors like octreotide and long acting depot preparations of lanreotide have also been shown to be feasible therapeutic options. Anti androgenic agents and PARP inhibitors have also been proposed as management options. Spontaneous bacterial peritonitis in the setting of malignancy in the absence of hepatic dysfunction has been reported to have a poorer prognosis than SBP in the setting of decompensated liver disease. Monomicrobial and polymicrobial bacterascites have been proposed in the absence of an elevated neutrophil ascitic fluid count that does not meet the diagnostic criteria. Extensive liver metastasis where the diseased liver can be expected to behave like a cirrhotic liver and gastrointestinal bleeding (on the basis of an isolated case report) have been considered as risk factors for the development of SBP in malignant ascites. In a case series of 8 patients with malignancy related ascites Patients with total ascitic fluid concentration of less than 1 gm per litre were found to be at risk for Spontaneous bacterial peritonitis and warrant flouroquinolone prophylaxis. Conclusion: Spontaneous Bacterial Peritonitis complicating malignant ascites is questionable entity. Good quality Audits and Randomised control trials are warranted to in this domain to enable the definition of incidence, antecedent complications, management and prophylaxis to ensure applicability of translational research to the clinical domain.
Rapports d'organisations sur le sujet "Multiple disease resistance"
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Sessa, Guido, et Gregory Martin. A functional genomics approach to dissect resistance of tomato to bacterial spot disease. United States Department of Agriculture, janvier 2004. http://dx.doi.org/10.32747/2004.7695876.bard.
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The research problem. Bacterial spot disease in tomato is of great economic importance worldwide and it is particularly severe in warm and moist areas affecting yield and quality of tomato fruits. Causal agent of spot disease is the Gram-negative bacterium Xanthomonas campestris pv. vesicatoria (Xcv), which can be a contaminant on tomato seeds, or survive in plant debris and in association with certain weeds. Despite the economic significance of spot disease, plant protection against Xcvby cultural practices and chemical control have so far proven unsuccessful. In addition, breeding for resistance to bacterial spot in tomato has been undermined by the genetic complexity of the available sources of resistance and by the multiple races of the pathogen. Genetic resistance to specific Xcvraces have been identified in tomato lines that develop a hypersensitive response and additional defense responses upon bacterial challenge. Central goals of this research were: 1. To identify plant genes involved in signaling and defense responses that result in the onset of resistance. 2. To characterize molecular properties and mode of action of bacterial proteins, which function as avirulence or virulence factors during the interaction between Xcvand resistant or susceptible tomato plants, respectively. Our main achievements during this research program are in three major areas: 1. Identification of differentially expressed genes during the resistance response of tomato to Xcvrace T3. A combination of suppression subtractive hybridization and microarray analysis identified a large set of tomato genes that are induced or repressed during the response of resistant plants to avirulent XcvT3 bacteria. These genes were grouped in clusters based on coordinate expression kinetics, and classified into over 20 functional classes. Among them we identified genes that are directly modulated by expression of the type III effector protein AvrXv3 and genes that are induced also during the tomato resistance response to Pseudomonas syringae pv. tomato. 2. Characterization of molecular and biochemical properties of the tomato LeMPK3MAP kinase. A detailed molecular and biochemical analysis was performed for LeMPK3 MAP kinase, which was among the genes induced by XcvT3 in resistant tomato plants. LeMPK3 was induced at the mRNA level by different pathogens, elicitors, and wounding, but not by defense-related plant hormones. Moreover, an induction of LeMPK3 kinase activity was observed in resistant tomato plants upon Xcvinfection. LeMPK3 was biochemically defined as a dual-specificity MAP kinase, and extensively characterized in vitro in terms of kinase activity, sites and mechanism of autophosphorylation, divalent cation preference, Kₘand Vₘₐₓ values for ATP. 3. Characteriztion of molecular properties of the Xcveffector protein AvrRxv. The avirulence gene avrRxvis involved in the genetic interaction that determines tomato resistance to Xcvrace T1. We found that AvrRxv functions inside the plant cell, localizes to the cytoplasm, and is sufficient to confer avirulence to virulent Xcvstrains. In addition, we showed that the AvrRxv cysteine protease catalytic core is essential for host recognition. Finally, insights into cellular processes activated by AvrRxv expression in resistant plants were obtained by microarray analysis of 8,600 tomato genes. Scientific and agricultural significance: The findings of these activities depict a comprehensive and detailed picture of cellular processes taking place during the onset of tomato resistance to Xcv. In this research, a large pool of genes, which may be involved in the control and execution of plant defense responses, was identified and the stage is set for the dissection of signaling pathways specifically triggered by Xcv.
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Michel Jr., Frederick C., Harry A. J. Hoitink, Yitzhak Hadar et Dror Minz. Microbial Communities Active in Soil-Induced Systemic Plant Disease Resistance. United States Department of Agriculture, janvier 2005. http://dx.doi.org/10.32747/2005.7586476.bard.
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Induced Systemic Resistance (ISR) is a highly variable property that can be induced by compost amendment of potting media and soils. For example, previous studies showed that only 1 of 79 potting mixes prepared with different batches of mature composts produced from several different types of solid wastes were able to suppress the severity of bacterial leaf spot of radish caused by Xanthomonas campestris pv. armoraciae compared with disease on plants produced in a nonamended sphagnum peat mix. In this project, microbial consortia in the rhizosphere of plants grown in ISR-active compost-amended substrates were characterized. The plants used included primarily cucumber but also tomato and radish. Rhizosphere microbial consortia were characterized using multiple molecular tools including DGGE (Israel) and T -RFLP (Ohio) in both ISR-active field plots and potting media. Universal as well as population-specific bacterial and fungal PCR primers were utilized. T -RFLP analyses using universal bacterial primers showed few significant differences in overall bacterial community composition in ISR-active and inactive substrates (Ohio). In addition, the community members which were significantly different varied when different ISR-activecomposts were used (Ohio). To better characterize the shifts in microbial community structure during the development of ISR, population specific molecular tools were developed (Israel, Ohio).-PCR primers were designed to detect and quantify bacterial groups including Pyrenomycetes, Bacillus, Pan toea, Pseudomonas, Xanthomonas and Streptomyces as well as Trichoderma and Fusarium; two groups of fungi that harbor isolates which are ISR active (Isreal and Ohio). Bacterial consortia associated with cucumber plants grown in compost-amended potting mixtures were shown to be dominated by the phylogenetic taxon Bacteroidetes, including members of the genus Chryseobacterium, which in some cases have been shown to be involved in biocontrol (Israel). Nested-PCR-DGGE analyses coupled with long l6S rDNA sequencing, demonstrated that the Chryseobacteriumspp. detected on seed and the root in compost-amended treatments were derived from the compost itself. The most effective ISR inducing rhizobacterial strains were identified as Bacillus sp. based on partial sequencing of l6S rDNA. However, these strains were significantly less effective in reducing the severity of disease than Trichoderma hamatum382 (T382). A procedure was developed for inoculation of a compost-amended substrate with T -382 which consistently induced ISR in cucumber against Phytophthora blight caused by Phytophthora capsiciand in radish against bacterial spot (Ohio). Inoculation of compost-amended potting mixes with biocontrol agents such as T -382 and other microbes that induce systemic resistance in plants significantly increased the frequency of systemic disease control obtained with natural compost amendments.
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Mawassi, Munir, Adib Rowhani, Deborah A. Golino, Avichai Perl et Edna Tanne. Rugose Wood Disease of Grapevine, Etiology and Virus Resistance in Transgenic Vines. United States Department of Agriculture, novembre 2003. http://dx.doi.org/10.32747/2003.7586477.bard.
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Rugose wood is a complex disease of grapevines, which occurs in all growing areas. The disease is spread in the field by vector transmission (mealybugs). At least five elongated-phloem- limited viruses are implicated in the various rugose wood disorders. The most fully characterized of these are Grapevine virus A (GV A) and GVB, members of a newly established genus, the vitivirus. GVC, a putative vitivirus, is much less well characterized than GV A or GVB. The information regarding the role of GVC in the etiology and epidemiology of rugose wood is fragmentary and no sequence data for GVC are available. The proposed research is aimed to study the etiology and epidemiology of rugose wood disease, and to construct genetically engineered virus-resistant grapevines. The objectives of our proposed research were to construct transgenic plants with coat protein gene sequences designed to induce post-transcriptional gene silencing (pTGS); to study the epidemiology and etiology of rugose wood disease by cloning and sequencing of GVC; and surveying of rugose wood- associated viruses in Californian and Israeli vineyards. In an attempt to experimentally define the role of the various genes of GV A, we utilized the infectious clone, inserted mutations in every ORF, and studied the effect on viral replication, gene expression, symptoms and viral movement. We explored the production of viral RNAs in a GV A-infected Nicotiana benthamiana herbaceous host, and characterized one nested set of three 5'-terminal sgRNAs of 5.1, 5.5 and 6.0 kb, and another, of three 3'-terminal sgRNAs of 2.2, 1.8 and 1.0 kb that could serve for expression of ORFs 2-3, respectively. Several GV A constructs have been assembled into pCAMBIA 230 I, a binary vector which is used for Angrobacterium mediated transformation: GV A CP gene; two copies of the GV A CP gene arranged in the same antisense orientation; two copies of the GV A CP gene in which the downstream copy is in an antigens orientation; GV A replicase gene; GV A replicase gene plus the 3' UTR sequence; and the full genome of GV A. Experiments for transformation of N. benthamiana and grapevine cell suspension with these constructs have been initiated. Transgenic N. benthamiana plants that contained the CP gene, the replicase gene and the entire genome of GV A were obtained. For grapevine transformation, we have developed efficient protocols for transformation and successfully grapevine plantlets that contained the CP gene and the replicase genes of GV A were obtained. These plants are still under examination for expression of the trans genes. The construction of transgenic plants with GV A sequences will provide, in the long run, a means to control one of the most prevalent viruses associated with grapevines. Our many attempts to produce a cDNA library from the genome of GVC failed. For surveying of rugose wood associated viruses in California vineyards, samples were collected from different grape growing areas and tested by RT-PCR for GV A, GVB and GVD. The results indicated that some of the samples were infected with multiple viruses, but overall, we found higher incidence of GVB and GV A infection in California vineyards and new introduction varieties, respectively. In this research we also conducted studies to increase our understanding of virus - induced rootstock decline and its importance in vineyard productivity. Our results provided supporting evidence that the rootstock response to virus infection depends on the rootstock genotype and the virus type. In general, rootstocks are differ widely in virus susceptibility. Our data indicated that a virus type or its combination with other viruses was responsible in virus-induced rootstock decline. As the results showed, the growth of the rootstocks were severely affected when the combination of more than one virus was present.
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Lamont, Susan J., E. Dan Heller et Avigdor Cahaner. Prediction of Immunocompetence and Resistance to Disease by Using Molecular Markers of the Major Histocompatibility Complex. United States Department of Agriculture, septembre 1994. http://dx.doi.org/10.32747/1994.7568780.bard.
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This project utilized two live-animal populations in an integrated research program to identify molecular markers for immune response and disease resistance. The populations each had their foundation from meat-type commercial breeder chicken lines of their respective countries. Investigations effectively used unique availability of resources in each country to study commercial-type environments in Israel and line-crosses with diverse inbred lines in the US. Two bacterial systems were investigated to cover both respiratory and gastrointestinal, and primary and secondary, infections. Individual experimental groups of animals were evaluated for combinations of vaccine antibody levels, response to pathogen challenge, growth parameters, genetic background and molecular markers. The positive association of antibody level with resistance to disease was confirmed. Effectiveness of genetic selection for vaccine antibody response level was demonstrated. Molecular markers, both inside and outside the MHC region, were associated with antibody response and resistance to disease. Markers were shown to have a generalized effect, by association with multiple traits of immune response and disease resistance. The impact of genetic background on marker effect was shown to be important. The overall results demonstrate the effectiveness of selection on vaccine antibody response and the potential of molecular marker-assisted selection to improve efficiency of production of meat-type chickens by reducing genetic susceptibility to disease.
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Thomas, Claude, Yigal Cohen, James McCreight et S. Nechama. Elucidation of the Genetic Basis of Multiple Disease Resistance in Cucumis Melo PI 124112 for Practical Application in the Development of Hybrids. United States Department of Agriculture, avril 1993. http://dx.doi.org/10.32747/1993.7603817.bard.
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Fahima, Tzion, et Jorge Dubcovsky. Map-based cloning of the novel stripe rust resistance gene YrG303 and its use to engineer 1B chromosome with multiple beneficial traits. United States Department of Agriculture, janvier 2013. http://dx.doi.org/10.32747/2013.7598147.bard.
Texte intégralRésumé :
Research problem: Bread wheat (Triticumaestivum) provides approximately 20% of the calories and proteins consumed by humankind. As the world population continues to increase, it is necessary to improve wheat yields, increase grain quality, and minimize the losses produced by biotic and abiotic stresses. Stripe rust, caused by Pucciniastriiformisf. sp. tritici(Pst), is one of the most destructive diseases of wheat. The new pathogen races are more virulent and aggressive than previous ones and have produced large economic losses. A rich source for stripe-rust resistance genes (Yr) was found in wild emmer wheat populations from Israel. Original Project goals: Our long term goal is to identify, map, clone, characterize and deploy in breeding, novel wild emmer Yr genes, and combine them with multiple beneficial traits. The current study was aiming to map and clone YrG303 and Yr15, located on chromosome 1BS and combine them with drought resistance and grain quality genes. Positional cloning of YrG303/Yr15: Fine mapping of these genes revealed that YrG303 is actually allelic to Yr15. Fine genetic mapping using large segregating populations resulted in reduction of the genetic interval spanning Yr15 to less than 0.1 cM. Physical mapping of the YrG303/Yr15 locus was based on the complete chromosome 1BS physical map of wheat constructed by our group. Screening of 1BS BAC library with Yr15 markers revealed a long BAC scaffold covering the target region. The screening of T. dicoccoidesaccession-specific BAC library with Yr15 markers resulted in direct landing on the target site. Sequencing of T. dicoccoidesBAC clones that cover the YrG303/Yr15 locus revealed a single candidate gene (CG) with conserved domains that may indicate a role in disease resistance response. Validation of the CG was carried out using EMS mutagenesis (loss-of- function approach). Sequencing of the CG in susceptible yr15/yrG303 plants revealed three independent mutants that harbour non-functional yr15/yrG303 alleles within the CG conserved domains, and therefore validated its function as a Pstresistance gene. Evaluation of marker-assisted-selection (MAS) for Yr15. Introgressions of Yr15 into cultivated wheat are widely used now. Recently, we have shown that DNA markers linked to Yr15 can be used as efficient tools for introgression of Yr15 into cultivated wheat via MAS. The developed markers were consistent and polymorphic in all 34 tested introgressions and are the most recommended markers for the introgression of Yr15. These markers will facilitate simultaneous selection for multiple Yr genes and help to avoid escapees during the selection process. Engineering of improved chromosome 1BS that harbors multiple beneficial traits. We have implemented the knowledge and genetic resources accumulated in this project for the engineering of 1B "super-chromosome" that harbors multiple beneficial traits. We completed the generation of a chromosome including the rye 1RS distal segment associated with improved drought tolerance with the Yr gene, Yr15, and the strong gluten allele 7Bx-over-expressor (7Bxᴼᴱ). We have completed the introgression of this improved chromosome into our recently released variety Patwin-515HP and our rain fed variety Kern, as well as to our top breeding lines UC1767 and UC1745. Elucidating the mechanism of resistance exhibited by Yr36 (WKS1). The WHEAT KINASE START1 (WKS1) resistance gene (Yr36) confers partial resistance to Pst. We have shown that wheat plants transformed with WKS1 transcript are resistant to Pst. WKS1 is targeted to the chloroplast where it phosphorylates the thylakoid-associatedascorbateperoxidase (tAPX) and reduces its ability to detoxify peroxides. Based on these results, we propose that the phosphorylation of tAPX by WKS1 reduces the ability of the cells to detoxify ROS and contributes to cell death. Distribution and diversity of WKS in wild emmer populations. We have shown that WKS1 is present only in the southern distribution range of wild emmer in the Fertile Crescent. Sequence analysis revealed a high level of WKS1 conservation among wild emmer populations, in contrast to the high level of diversity observed in NB-LRR genes. This phenomenon shed some light on the evolution of genes that confer partial resistance to Pst. Three new WKS1 haplotypes displayed a resistance response, suggesting that they can be useful to improve wheat resistance to Pst. In summary, we have improved our understanding of cereals’ resistance mechanisms to rusts and we have used that knowledge to develop improved wheat varieties.
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Reisch, Bruce, Avichai Perl, Julie Kikkert, Ruth Ben-Arie et Rachel Gollop. Use of Anti-Fungal Gene Synergisms for Improved Foliar and Fruit Disease Tolerance in Transgenic Grapes. United States Department of Agriculture, août 2002. http://dx.doi.org/10.32747/2002.7575292.bard.
Texte intégralRésumé :
Original objectives . 1. Test anti-fungal gene products for activity against Uncinula necator, Aspergillus niger, Rhizopus stolonifer and Botrytis cinerea. 2. For Agrobacterium transformation, design appropriate vectors with gene combinations. 3. Use biolistic bombardment and Agrobacterium for transformation of important cultivars. 4. Characterize gene expression in transformants, as well as level of powdery mildew and Botrytis resistance in foliage of transformed plants. Background The production of new grape cultivars by conventional breeding is a complex and time-consuming process. Transferring individual traits via single genes into elite cultivars was proposed as a viable strategy, especially for vegetatively propagated crops such as grapevines. The availability of effective genetic transformation procedures, the existence of genes able to reduce pathogen stress, and improved in vitro culture methods for grapes, were combined to serve the objective of this proposal. Effective deployment of resistance genes would reduce production costs and increase crop quality, and several such genes and combinations were used in this project. Progress The efficacy of two-way combinations of Trichoderma endochitinase (CHIT42), synthetic peptide ESF12 and resveratrol upon the control of growth of Botrytis cinerea and Penicillium digitatum were evaluated in vitro. All pairwise interactions were additive but not synergistic. Per objective 2, suitable vectors with important gene combinations for Agrobacterium transformation were designed. In addition, multiple gene co-transformation by particle bombardment was also tested successfully. In New York, transformation work focused on cultivars Chardonnay and Merlot, while the technology in Israel was extended to 41B, R. 110, Prime, Italia, Gamay, Chardonnay and Velika. Transgenic plant production is summarized in the appendix. Among plants developed in Israel, endochitinase expression was assayed via the MuchT assay using material just 1-5 days after co-cultivation. Plants of cv. Sugraone carrying the gene coding for ESF12, a short anti-fungal lytic peptide under the control of the double 358 promoter, were produced. Leaf extracts of two plants showed inhibition zones that developed within 48 h indicating the inhibitory effect of the leaf extracts on the six species of bacteria. X fastidiosa, the causal organism of Pierce's disease, was very sensitive to leaf extracts from ESF12 transformed plants. Further work is needed to verify the agricultural utility of ESF12 transformants. In New York, some transformants were resistant to powdery mildew and Botrytis fruit rot. Major conclusions, solutions, achievements and implications The following scientific achievements resulted from this cooperative BARD project: 1. Development and improvement of embryogenesis and tissue culture manipulation in grape, while extending these procedures to several agriculturally important cultivars both in Israel and USA. 2. Development and improvement of novel transformation procedures while developing transformation techniques for grape and other recalcitrant species. 3. Production of transgenic grapevines, characterization of transformed vines while studying the expression patterns of a marker gene under the control of different promoter as the 35S CaMV in different part of the plants including flowers and fruits. 4. Expression of anti-fungal genes in grape: establishment of transgenic plants and evaluation of gene expression. Development of techniques to insert multiple genes. 5. Isolation of novel grape specific promoter to control the expression of future antimicrobial genes. It is of great importance to report that significant progress was made in not only the development of transgenic grapevines, but also in the evaluation of their potential for increased resistance to disease as compared with the non engineered cultivar. In several cases, increased disease resistance was observed. More research and development is still needed before a product can be commercialized, yet our project lays a framework for further investigations.
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Cahaner, Avigdor, Susan J. Lamont, E. Dan Heller et Jossi Hillel. Molecular Genetic Dissection of Complex Immunocompetence Traits in Broilers. United States Department of Agriculture, août 2003. http://dx.doi.org/10.32747/2003.7586461.bard.
Texte intégralRésumé :
Objectives: (1) Evaluate Immunocompetence-OTL-containing Chromosomal Regions (ICRs), marked by microsatellites or candidate genes, for magnitude of direct effect and for contribution to relationships among multiple immunocompetence, disease-resistance, and growth traits, in order to estimate epistatic and pleiotropic effects and to predict the potential breeding applications of such markers. (2) Evaluate the interaction of the ICRs with genetic backgrounds from multiple sources and of multiple levels of genetic variation, in order to predict the general applicability of molecular genetic markers across widely varied populations. Background: Diseases cause substantial economic losses to animal producers. Emerging pathogens, vaccine failures and intense management systems increase the impact of diseases on animal production. Moreover, zoonotic pathogens are a threat to human food safety when microbiological contamination of animal products occurs. Consumers are increasingly concerned about drug residues and antibiotic- resistant pathogens derived from animal products. The project used contemporary scientific technologies to investigate the genetics of chicken resistance to infectious disease. Genetic enhancement of the innate resistance of chicken populations provides a sustainable and ecologically sound approach to reduce microbial loads in agricultural populations. In turn, animals will be produced more efficiently with less need for drug treatment and will pose less of a potential food-safety hazard. Major achievements, conclusions and implications:. The PI and co-PIs had developed a refined research plan, aiming at the original but more focused objectives, that could be well-accomplished with the reduced awarded support. The successful conduct of that research over the past four years has yielded substantial new information about the genes and genetic markers that are associated with response to two important poultry pathogens, Salmonella enteritidis (SE) and Escherichia coli (EC), about variation of immunocompetence genes in poultry, about relationships of traits of immune response and production, and about interaction of genes with environment and with other genes and genetic background. The current BARD work has generated a base of knowledge and expertise regarding the genetic variation underlying the traits of immunocompetence and disease resistance. In addition, unique genetic resource populations of chickens have been established in the course of the current project, and they are essential for continued projects. The US laboratory has made considerable progress in studies of the genetics of resistance to SE. Microsatellite-marked chromosomal regions and several specific genes were linked to SE vaccine response or bacterial burden and the important phenomenon of gene interaction was identified in this system. In total, these studies demonstrate the role of genetics in SE response, the utility of the existing resource population, and the expertise of the research group in conducting such experiments. The Israeli laboratories had showed that the lines developed by selection for high or low level of antibody (Ab) response to EC differ similarly in Ab response to several other viral and bacterial pathogens, indicating the existence of a genetic control of general capacity of Ab response in young broilers. It was also found that the 10w-Ab line has developed, possibly via compensatory "natural" selection, higher cellular immune response. At the DNA levels, markers supposedly linked to immune response were identified, as well as SNP in the MHC, a candidate gene responsible for genetic differences in immunocompetence of chickens.
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Shpigel, Nahum, Raul Barletta, Ilan Rosenshine et Marcelo Chaffer. Identification and characterization of Mycobacterium paratuberculosis virulence genes expressed in vivo by negative selection. United States Department of Agriculture, janvier 2004. http://dx.doi.org/10.32747/2004.7696510.bard.
Texte intégralRésumé :
Mycobacterium avium subsp. paratuberculosis (MAP) is the etiological agent of a severe inflammatory bowel disease (IBD) in ruminants, known as Johne’s disease or paratuberculosis. Johne’s disease is considered to be one of the most serious diseases affecting dairy cattle both in Israel and worldwide. Heavy economic losses are incurred by dairy farmers due to the severe effect of subclinical infection on milk production, fertility, lower disease resistance and early culling. Its influence in the United States alone is staggering, causing an estimated loss of $1.5 billion to the agriculture industry every year. Isolation of MAP from intestinal tissue and blood of Crohn's patients has lead to concern that it plays a potential pathogenic role in promoting human IDB including Crohn’s disease. There is great concern following the identification of the organism in animal products and shedding of the organism to the environment by subclinically infected animals. Little is known about the molecular basis for MAP virulence. The goal of the original proposed research was to identify MAP genes that are required for the critical stage of initial infection and colonization of ruminants’ intestine by MAP. We proposed to develop and use signature tag mutagenesis (STM) screen to find MAP genes that are specifically required for survival in ruminants upon experimental infection. This research projected was approved as one-year feasibility study to prove the ability of the research team to establish the animal model for mutant screening and alternative in-vitro cell systems. In Israel, neonatal goat kids were repeatedly inoculated with either one of the following organisms; MAP K-10 strain and three transposon mutants of K-10 which were produced and screened by the US PI. Six months after the commencement of inoculation we have necropsied the goats and taken multiple tissue samples from the jejunum, ileum and mesenteric lymph nodes. Both PCR and histopathology analysis indicated on efficient MAP colonization of all the inoculated animals. We have established several systems in the Israeli PI’s laboratory; these include using IS900 PCR for the identification of MAP and using HSP65-based PCR for the differentiation between MAV and MAP. We used Southern blot analysis for the differentiation among transposon mutants of K-10. In addition the Israeli PI has set up a panel of in-vitro screening systems for MAP mutants. These include assays to test adhesion, phagocytosis and survival of MAP to/within macrophages, assays that determine the rate of MAPinduced apoptosis of macrophages and MAP-induced NO production by macrophages, and assays testing the interference with T cell ã Interferon production and T cell proliferation by MAP infected macrophages (macrophage studies were done in BoMac and RAW cell lines, mouse peritoneal macrophages and bovine peripheral blood monocytes derived macrophages, respectively). All partners involved in this project feel that we are currently on track with this novel, highly challenging and ambitious research project. We have managed to establish the above described research systems that will clearly enable us to achieve the original proposed scientific objectives. We have proven ourselves as excellent collaborative groups with very high levels of complementary expertise. The Israeli groups were very fortunate to work with the US group and in a very short time period to master numerous techniques in the field of Mycobacterium research. The Israeli group has proven its ability to run this complicated animal model. This research, if continued, may elucidate new and basic aspects related to the pathogenesis MAP. In addition the work may identify new targets for vaccine and drug development. Considering the possibility that MAP might be a cause of human Crohn’s disease, better understanding of virulence mechanisms of this organism might also be of public health interest as well.
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Rahimipour, Shai, et David Donovan. Renewable, long-term, antimicrobial surface treatments through dopamine-mediated binding of peptidoglycan hydrolases. United States Department of Agriculture, janvier 2012. http://dx.doi.org/10.32747/2012.7597930.bard.
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There is a need for renewable antimicrobial surface treatments that are semi- permanent, can eradicate both biofilms and planktonic pathogens over long periods of time and that do not select for resistant strains. This proposal describes a dopamine binding technology that is inexpensive, bio-friendly, non-toxic, and uses straight-forward commercially available products. The antimicrobial agents are peptidoglycanhydrolase enzymes that are non-toxic and highly refractory to resistance development. The goal of this project is to create a treatment that will be applicable to a wide variety of surfaces and will convey long-lasting antimicrobial activity. Although the immediate goal is to create staphylolytic surfaces, the technology should be applicable to any pathogen and will thus contribute to no less than 3 BARD priorities: 1) increased animal production by protecting animals from invasive and emerging diseases, 2) Antimicrobial food packaging will improve food safety and security and 3) sustainable bio- energy systems will be supported by coating fermentation vats with antimicrobials that could protect ethanolic fermentations from Lactobacillus contamination that reduces ethanol yields. The dopamine-based modification of surfaces is inspired by the strong adhesion of mussel adhesion proteins to virtually all types of surfaces, including metals, polymers, and inorganic materials. Peptidoglycanhydrolases (PGHs) meet the criteria of a surface bound antimicrobial with their site of action being extracellular peptidoglycan (the structural basis of the bacterial cell wall) that when breached causes osmotic lysis. As a proof of principle, we will develop technology using peptidoglycanhydrolase enzymes that target Staphylococcus aureus, a notoriously contagious and antimicrobial-resistant pathogen. We will test for susceptibility of the coating to a variety of environmental stresses including UV light, abrasive cleaning and dessication. In order to avoid resistance development, we intend to use three unique, synergistic, simultaneous staphylococcal enzyme activities. The hydrolases are modular such that we have created fusion proteins with three lytic activities that are highly refractory to resistance development. It is essential to use multiple simultaneous activities to avoid selecting for antimicrobial resistant strains. This strategy is applicable to both Gram positive and negative pathogens. We anticipate that upon completion of this award the technology will be available for commercialization within the time required to achieve a suitable high volume production scheme for the required enzymes (~1-2 years). We expect the modified surface will remain antimicrobial for several days, and when necessary, the protocol for renewal of the surface will be easily applied in a diverse array of environments, from food processing plants to barnyards.