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1
Paniccia, Rocco. "Detection of nucleoplasmic glycoconjugates using lectin cytochemistry." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59968.
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The lectins Ulex europaeus 1 (UEA 1), Ricinus communis 1 (RCA 1), Wheat Germ Agglutinin (WGA), and Lens culinaris agglutinin (LCA) which are specific for L-fucose, D-galactose, N-acetylglucosamine, and D-mannose respectively, have been used to localize cytochemically the presence of these sugar residues in certain human, mammalian, and amphibian cell types. Thin sections of Lowicryl K4M-embedded human distal colon, rat duodenum, and frog dorsal root ganglion were incubated with UEA 1-gold, RCA 1-gold, WGA/ovomucoid-gold, or LCA-gold. UEA-1, RCA-1, and LCA binding sites were present in the nuclei of human colonic cells, rat duodenal goblet and columnar cells and frog dorsal root ganglion neurons, satellite cells, and Schwann cells. Most of the nuclear binding sites were localized in the euchromatin compartment, while extranuclear labelling was largely restricted to sites known to contain glycoproteins. WGA binding sites were present in the nuclei of rat duodenum columnar cells and frog dorsal root ganglion neurons, satellite cells, and Schwann cells, but no labelling of human colonic cell nuclei was observed. Thus, we report the presence of these sugars in the nuceloplasm of human colonic cells (with the exception of WGA), rat duodenal villous columnar cells, and frog dorsal root ganglion cells examined.
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Henry, Yvonne. "An ultrastructural study of the secretory cycle in digestive glands of Dionaea muscipula Ellis." Thesis, Queen's University Belfast, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235851.
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Long, Joel Andrew. "Ultrastructure and cytochemistry of sporogenesis in two bryophytes, Notothylas and Takakia /." Available to subscribers only, 2006. http://proquest.umi.com/pqdweb?did=1251821251&sid=10&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Song, Xiu-Zhen. "Immunocytochemical localization of photosystems I and II in the green alga Tetraselmis subcordiformis." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=26152.
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The distribution of photosystem I (PS I) and photosystem II (PS II) in a primitive green alga Tetraselmis subcordiformis, which belongs to Prasinophyceae and does not have grana in its chloroplast, was studied by immunoelectron microscopy. Two PS I antibodies were used: one against a PS I component of maize, the other against the 60 and 62 KDa PS I reaction centre proteins of the cyanobacterium Synechococcus elongatus. Both antibodies showed that 76-78% of the labelling is on the appressed thylakoid membranes and only 22-24% is located on the unappressed membranes. Use of antiserum against cp-47 of PS II from S. elongatus also gives 76% of the labelling on appressed thylakoid membranes and 24% on unappressed thylakoid membranes. Cytochemical detection of PS I activity by the photooxidation of 3,3$ sp prime$-diaminobenzidine and of PS II activity by the photoreduction of distyryl nitroblue tetrazolium chloride also revealed that PS I and PS II activities exist on both types of thylakoid membranes. Therefore, our results indicate that the distribution of PS I and PS II in green algae may differ from that in higher plants.
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Wang, Yuchong. "High-throughput investigations of the sub-cellular localisation of proteins and lipids in Saccharomyces cerevisiae." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709145.
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Stenzel, Deborah Joan. "Ultrastructural and cytochemical studies of blastocystis sp." Thesis, Queensland University of Technology, 1994.
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Ameye, Laurent. "Control of biomineralization in echinoderms :ultrastructure and cytochemistry of the organic matrix." Doctoral thesis, Universite Libre de Bruxelles, 1999. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211943.
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Soole, Kathleen Lydia. "Characterisation of the NADH dehydrogenases associated with isolated plant mitochondria /." Title page, contents and summary only, 1989. http://web4.library.adelaide.edu.au/theses/09PH/09phs711.pdf.
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Tang, Liang. "Characterization of tubulins from parasitic nematodes (Brugia malayi, B. pahangi and Nippostrongylus brasiliensis) and comparison with mammalian brain tubulin." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75933.
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The properties of tubulins from Brugia malayi, B. pahangi, Nippostrongylus brasiliensis and rat brain were compared. Tubulins from all nematodes and rat brain were partially purified by polylysine agarose chromatography, those of brain also by cycles of assembly/disassembly, and all by taxol-induced assembly. The tubulins were compared with respect to concentration ($ mu$g tubulin/mg soluble protein), drugs binding and isoforms. The tubulins of B. malayi and B. pahangi were similar. However, the tubulin from these filariae were different from those of N. brasiliensis. Even larger differences were detected between the nematode tubulins and those of rat brain. However, all tubulins reacted to $ alpha$- and $ beta$-tubulin monoclonal antibodies, and had similar mobility on SDS-PAGE. Different peptide maps were obtained for N. brasiliensis tubulin compared with rat brain tubulin. Tubulins of N. brasiliensis bound more mebendazole than did those of Brugia nematodes (B$ sb{ rm max}$: pmoles/$ mu$g tubulin). The binding of benzimidazoles to nematode tubulins was much higher than to rat brain tubulin. Benzimidazole binding to brain tubulin was influenced by the degree of assembly of the tubulin. This did not appear to be the case for the nematode tubulins. In vitro translation of B. malayi mRNA resulted in two isoforms for both $ alpha$- and $ beta$-tubulins in contrast to the 4 $ alpha$- and 4-5 $ beta$-isoforms found naturally. This suggest post translational modification of tubulin may take place in B. malayi. This study has characterized some of the differences that exist between mammalian tubulins and those of nematodes on the one hand, and between the tubulins of a gastrointestinal nematode (N. brasiliensis) and those of filariae (B. malayi and B. pahangi) on the other hand.
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Dragoi, Ana-Maria. "Unraveling the mechanism and role of AKT activation by CpG-DNA." View abstract/electronic edition; access limited to Brown University users, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3318309.
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Mutasa, H. C. F. "Cytology, cytochemistry and ultrastructure of blood cells with special reference to myeloid leukaemias." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335133.
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Ribeiro, Viktoria Kovesdy. "Analise das reservas de sementes de especies arboreas da restinga do municipio de Ipojuca-PE." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316634.
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Orientador: Angelo Luiz CortelazzoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-07T07:38:47Z (GMT). No. of bitstreams: 1 Ribeiro_ViktoriaKovesdy_M.pdf: 7983680 bytes, checksum: 5d4ac508a6df0a6cc6853aab29ae2d9a (MD5) Previous issue date: 2006
Resumo: As restingas da região nordeste são pouco estudadas em todos os seus aspectos. Assim, o presente trabalho teve como objetivo analisar sementes de espécies de grande ocorrência na restinga da Reserva Particular do Patrimônio Nacional (RPPN) de Nossa Senhora do Outeiro de Maracaípe em Ipojuca, no litoral pernambucano, dentro de uma perspectiva mais ampla de análise para contribuir com o conhecimento de sua estrutura e das potencialidades de utilização econômica junto à população local. Foram coletadas sementes de 22 espécies, que foram fixadas em solução de FAA 70 ou fixador de Karnovsky para processamento e análise microscópica. Destas, oito espécies foram incluídas em historesina Leica ou em parafina, seguindo-se corte em micrótomo com 5 a 8 cm de espessura, conforme o meio de inclusão: Coccoloba laevis Casar. (Polygonaceae), Licania rigida (Chrysobalanaceae), Myrcia guianensis (Aulb.) DC. (Myrtaceae), Simaba cuneata A.St.-Hil. & Tul. (Simaroubaceae), Manilkara salzmannii (A.DC.) Lam (Sapotaceae), Maytenus impressa Reiss. (Celastraceae), Ocotea gardneri (Meisn.) Meiz (Lauraceae) e Serjania sp (Sapindaceae). Os materiais foram corados por diversos métodos gerais e citoquímicos, visando a determinação de proteínas, polissacarídeos, lipídios, radicais aniônicos totais e compostos fenólicos. Para as quatro primeiras espécies citadas, foram dosadas as principais reservas presentes nas sementes. Os resultados citoquímicos foram confirmados pelas dosagens bioquímicas revelando que C. laevis é uma espécie onde predomina o amido, L. rígida tem maiores teores de proteínas e S. cuneata é oleaginosa. M guianensis mostrou-se moderadamente rica em carboidratos e proteínas. Chamou a tenção a incomum quantidade de açúcares livres presentes nas sementes, que variou de 10% em C. laevis até 25% em L. rígida, podendo representar fator adaptativo interessante à falta de água. Cristais de oxalato, presença de taninos e tegumento lignificado também foram características encontradas na maioria das espécies e também podem estar relacionadas à defesa e estratégias de dispersão das sementes. Os testes citoquímicos revelaram ainda que O. gardneri e Serjania sp são ricas em amido e proteínas, enquanto que M. salzmannii apresenta lipídios em quantidades apreciáveis. Finalmente, pôde ser notado que M. impressa apresenta endosperma bem desenvolvido, possivelmente com hemiceluloses como sua principal reserva; seus cotilédones apresentaram quantidades apreciáveis de proteínas. As demais espécies coletadas encontram-se processadas para inclusão e corte para futura análise e caracterização citoquímica
Abstract: ¿ Restinga of the northeast have been barely studied in all their aspects. Thus, this work was as objective analyzes seeds of arboreal species of great occurrence in the ¿Reserva Particular do Patrimônio Nacional (RPPN) de Nossa Senhora do Outeiro de Maracaípe¿ in Ipojuca, located at the sea coast of Pernambuco to contribute with the knowledge of structure and these economic potentialities. Twenty-two species of fruits were harvested and the seeds were fixed in FAA70 or Karnovsky solutions and processed for microscopic analysis. Of these, eight species were embedded in Leica Historesin or paraffin and sectioned (5-7cm thick): Coccoloba laevis Casar. (Polygonaceae), Licania rigida (Chrysobalanaceae), Myrcia guianensis (Aulb.) DC. (Myrtaceae), Simaba cuneata A.St.-Hil. & Tul. (Simaroubaceae), Manilkara salzmannii (A.DC.) Lam (Sapotaceae), Maytenus impressa Reiss. (Celastraceae), Ocotea gardneri (Meisn.) Meiz (Lauraceae) and Serjania sp (Sapindaceae). After removing the paraffin and hydration, the materials were stained using several cytochemical methods to detect anionic residues, proteins, polysaccharides, starch, lipids and lignin. The stained sections were examined by light microscopy, using polarized light in some cases. The first four mentioned species of seeds were submitted to extraction to detect their principal reserves. The cytochemical results were confirmed by biochemical dosage revealing that C. laevis is a species where the starch is predominant; L. rigida has got higher contents of proteins and S. cuneata is oleaginous. M guianensis showed moderately rich in carbohydrates and proteins. Free and soluble sugars presented an unusual quantity in the seeds, with variation from 10% in C. laevis up to 25% in L. rigida , showing an possible and interesting adaptative factor to lack of water. Oxalate crystals, presence of tannins and lignified teguments were also characteristics found in most of the species and can be related to the defense and strategies of dispersion of the seeds. The cytochemical analysis revealed that although O. gardneri and Serjania sp are rich in starch and proteins, M. salzmannii presents lipids in appreciable amounts. Finally, it could be found that M. impressa presents endosperm well developed, possibly with hemiceluloses as the principal reserve while their cotyledons presented appreciable amounts of proteins. The other harvested fruits and seeds were processed for embebition and cut for future analysis and cytochemical characterization
Mestrado
Biologia Celular
Mestre em Biologia Celular e Estrutural
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Larous, Larbi. "Comparative ultrastructure and cytochemistry of rust infections, with particular reference to Puccinia menthae and Uromyces vicia-fabae." Thesis, University of Sheffield, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294389.
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uk, k. hulme-moir@vet gla ac, and Karen Lisa Hulme-Moir. "Structure and Function of Leukocytes in the Family Macropodidae." Murdoch University, 2007. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20100211.90101.
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Leukocytes play a central role in protecting the body against infectious organisms and their research is essential for understanding the mechanisms of immunity. By studying leukocytes across a range of species, insights are provided into differing strategies employed to ensure resistance to disease. Surprisingly, the structure and function of marsupial leukocytes has received very limited study. Marsupials represent a major evolutionary pathway with distinct differences in reproduction and development from placental mammals. These differences in the life history of marsupials place unique challenges on the immune system, and differences in leukocyte structure and function could be reasonably expected. In this thesis, studies were undertaken to examine the cytochemical, ultrastructural and functional features of leukocytes from species of marsupials, belonging to the family Macropodidae (kangaroos and wallabies). The aim of these studies was to elucidate the characteristics of macropodid leukocytes and to compare and contrast these features with the known characteristics of other mammalian leukocytes.
Leukocytes from two species of macropodid, the tammar wallaby (Macropus eugenii) and the western grey kangaroo (Macropus fuliginosis), formed the basis of this study with additional material provided from quokka (Setonix brachyurus), woylie (Bettongia pencillata) and red kangaroo (Macropus rufus). Staining characteristics of cells were examined following reaction with Sudan black B, peroxidase, chloroacetate esterase, naphthyl butyrate esterase, alkaline phosphatase and periodic acid-Schiff. Peroxidase and Sudan Black B reactions were similar to domestic animal species but chloroacetate esterase and naphthyl butyrate esterase were unreliable as markers for macropodid neutrophils and monocytes, respectively. Significant variation in staining for alkaline phosphatase was seen between species of macropodid. Tammar wallabies and quokka demonstrated strong neutrophil alkaline phosphatase activity whereas western grey kangaroos, red kangaroos and woylies contained no activity within their leukocytes.
Peroxidase and alkaline phosphatase cytochemistry were also assessed at the ultrastructural level with transmission electron microscopy. This allowed the identification of distinct granule populations within macropodid neutrophils. Two subcellular compartments containing alkaline phosphatase activity were identified within tammar wallaby neutrophils. These were considered equivalent to secretory vesicles and a subpopulation of specific granules. Tubular vesicles containing alkaline phosphatase were also identified within the eosinophils of tammar wallabies. These structures were a novel finding having not been reported previously in the eosinophils of other animal species.
In addition to cytochemistry, the general ultrastructure of leukocytes from tammar wallabies and western grey kangaroos were reported. Results were similar to previous reports for other marsupial species. The current body of knowledge was extended by the first detailed description of the ultrastructure of basophils in a marsupial.
To assess functional aspects of macropdid neutrophils, flow cytometric assays were performed examining oxidative burst responses and phagocytosis. Reactive oxygen species were generated by neutrophils from tammar wallabies and western grey kangaroos in response to phorbol 12-myristate 13-acetate but not N-formyl-Met-Leu-Phe or opsonised bacteria. Phagocytosis of opsonised bacteria was also measured in neutrophils from tammar wallabies, which was poor in contrast to ovine neutrophils. However, flow cytometric studies were limited by sample preparation. Further optimisation of isolation methods for tammar wallaby leukocytes should be undertaken before dogmatic conclusions are drawn.
Overall, the results of this thesis demonstrate that, in the areas examined, the general characteristics of leukocyte structure and function of mammals are present in macropodids. However differences were identified both within and outside of the macropodid group. These differences have important ramifications for the use of model species in the study of leukocyte biology in marsupials. The results also provide potentially useful tools for the clinical diagnosis of haematological disease in macropodids and may be of interest to those studying comparative and evolutionary aspects of leukocyte structure and function.
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Sinha, Neeti. "Cytochrome c biogenesis in bacteria." Thesis, University of Oxford, 1998. http://ora.ox.ac.uk/objects/uuid:798d9c8a-42ef-4de4-a889-5cdbf5951540.
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Cytochromes c are electron transfer proteins in which haem is covalently attached to the polypeptide chain via thioether bonds formed from thiol groups of the two cysteines and the two vinyl groups of haem. This attachment is a post translational process and in many species of bacteria as many as approximately twelve gene products, the functions of which are largely unknown, are required. In Gram-negative bacteria the assembly of the c-type cytochromes occurs in the periplasm. Cytochrome c552 from the thermophilic organism Hydrogenobacter thermophilus is known to be expressed in the cytoplasm of Escherichia coli. This unique example of cytoplasmic assembly of a c-type cytochrome has previously been postulated to result from insertion of haem into the folded apoform of the cytochrome followed by non-catalysed attachment of the haem. This postulate is supported by the present work which has shown that the cytoplasmic assembly of this cytochrome c552 continues in the absence of the E. coli ccm genes which are needed for 'normal' c-type cytochrome assembly in that organism. Attempts to test the postulate of spontaneous assembly of the cytochrome c552 with in vitro experiments require large amounts of cytochrome c552 and its apo protein. A number of procedures for preparing these proteins were investigated. Although a T7-based expression produced lower amounts than was expected, its use led to detection of the apo form of cytochrome c552 in E. coli. It was shown that this apoform has some secondary structure, whereas mitochondrial apocytochrome c has a random coil conformation. This observation is consistent with, but does not prove, the postulate for cytochrome c552 assembly. It was unexpectedly found that a strain of E. coli that produces abnormally large amounts of its endogenous c-type cytochromes also made large amounts of cytoplasmic cytochrome c552. NMR studies on this material are consistent with a single and 'normal' attachment of the haem to the polypeptide. Thus the unusual cytoplasmic assembly was not different from the usual periplasmic assembly that occurs in the H. thermophilus itself. In E. coli there is a periplasmic cytochrome b562 that is presumed to acquire its haem in the periplasm. Some of the ccm genes, required for c-type cytochrome assembly, are postulated to code for a system that transports haem to the periplasm. Cytochrome b- 562 synthesis was not blocked by the absence of these genes. This implies that haem provision for cytochrome b562 synthesis occurs independently of the ccm system. Apocytochrome b562 could be detected in E. coli with the ratio apo:holo being higher in a strain that produces c-type cytochromes to relatively low levels. It is suggested that the synthesis of both cytochrome b562 and c-type cytochromes is at least partly a reflection of the rate of production of haem by the cells.
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Lombard, Nicolaas. "The isolation and charcterisation of ovine liver cytochrome b₅." Thesis, Stellenbosch : Stellenbosch University, 2007. http://hdl.handle.net/10019.1/19448.
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Dissertation (PhD)--University of Stellenbosch, 2007.ENGLISH ABSTRACT: This dissertation describes how the isolation and characterisation of ovine liver cytochrome b5 was accomplished by referring to the following goals achieved in this study: - The optimisation of the isolation and purification procedure for ovine liver microsomal cytochrome b5 in order to obtain sufficient material for aggregation and immunological studies. - The removal of the membrane binding domain of cytochrome b5 by means of tryptic digestion to establish the role of the carboxyl terminal in ovine cytochrome b5 aggregation. - The raising of antibodies against both the trypsin truncated and intact forms of cytochrome b5 to study the aggregation of the protein. - The investigation into the influence of purified cytochrome b5 on steroidogenesis in ovine adrenal microsomes.
AFRIKAANSE OPSOMMING: Die isolering en karakterisering van skaaplewersitochroom b5, soos beskryf in hierdie proefskrif, is uitgevoer deur die volgende doelwitte suksesvol af te handel: - Die optimalisering van die prosedure vir die suksesvolle isolering en suiwering van skaaplewersitochroom b5 ten einde genoegsame hoeveelhede van die suiwer proteïen te hê vir die bestudering van die aggregasie van die proteïen sowel as ‘n immunologiese studie. - Die verwydering van die membraanbindingsdomein van sitochroom b5 om die invloed van die karboksielterminaal op die aggregering van die proteïen te bestudeer. - Die gebruik van sowel die tripties gesnyde as die intakte vorms van sitochroom b5 om ‘n immuunrespons in hase op te wek vir die verkryging van sitochroom b5 spesifieke anti-liggame. - Die gebruik van die gesuiwerde proteïene om die invloed van sitochroom b5 op adrenale steroïdogenese te bestudeer.
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Moller, Cheryl. "The haematology of bobtail lizards (Tiliqua rugosa) in Western Australia: reference intervals, blood cell morphology, cytochemistry and ultrastructure." Thesis, Moller, Cheryl (2014) The haematology of bobtail lizards (Tiliqua rugosa) in Western Australia: reference intervals, blood cell morphology, cytochemistry and ultrastructure. Masters by Research thesis, Murdoch University, 2014. https://researchrepository.murdoch.edu.au/id/eprint/22862/.
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Bobtail lizards (Tiliqua rugosa) are native to Western Australia. Haematological evaluation is useful for health assessment: the only previous study of the haematology of this species sampled just six lizards (Canfield and Shea, 1988). The main aim of this study was to produce reference intervals for bobtail haematology.
Over the summers of 2011/12 and 2012/13, heparinised venous blood was collected from 46 clinically healthy, captive adult bobtails in Perth. Complete blood counts and blood smear evaluations were performed. Cytochemical stains, transmission electron microscopy, and bone marrow cytology and histology facilitated further characterisation of the blood cells. Reference intervals with 90% confidence intervals were determined using Reference Value Advisor freeware (Geffré et al., 2011). The packed cell volume (PCV) was 0.10-0.44L/L (n=40). Total plasma protein by refractometry was 36-74g/L (n=39). Haemoglobin was 20-154g/L (n=32). The manual red and white blood cell counts were 0.28-1.03x1012/L (n=38) and 2.75-30.76 x109/L (n=39), respectively.
Blood cell morphology was similar to that of other lizards - except the eosinophils which were uniformly vacuolated. A 200 cell leukocyte differential count was performed on each smear (n=46). Heterophils predominated (27-88%), with fewer lymphocytes (0-34%) and monocytes (1-27%), occasional eosinophils (0-22%) and basophils (0-20%). Thrombocytes were frequently clumped or present as bare nuclei. Slight polychromasia (0-7%) was typically present (n=45).
Many reference intervals were wide, particularly PCV, haemoglobin and white blood cell count. This was not unexpected as reptile haematology is influenced by many preanalytical factors.
Smears from 13 bobtails contained haemogregarine parasites, identified as probable Hemolivia species. There was evidence that this infection caused mild erythrocyte pathology.
The reference intervals were applied to the haematology of seven bobtails hospitalised with upper respiratory tract disease. Six bobtails possessed haematological evidence of inflammation. Thus the reference intervals appear to be clinically useful for the haematological assessment of captive bobtail lizards.
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Adriaanse, Craig Vernon. "An investigation into the complex formation of membrane bound cytochrome b5 isolated from ovine liver microsomes." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85653.
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Thesis (MSc)-- Stellenbosch University, 2013.ENGLISH ABSTRACT: Membrane bound cytochrome b5 is a ubiquitous protein with an average molecular weight of 16 kDa. The protein is involved in a number of reactions providing electrons directly to cytochrome P450 enzymes or to other enzymes involved in lipid biosynthesis. It is also known that the protein influences the activities of certain enzymes via an allosteric effect. It has been accepted in the literature that the cytochrome b5 exists primarily in the monomeric form, however, recently it has been shown that it forms homomeric complexes in vivo. In this study, we investigate the cytochrome b5 complex formation using a variety of analytical tools. Cytochrome b5 was isolated from ovine liver microsomes and the purity verified using sodium dodecyl sulphate polyacrylamide gel electrophoresis and electrospray ionisation mass spectrometry. The latter analysis confirmed the presence of a single heme containing protein with Mr=15865 Da, while separation on the polyacrylamide gel revealed oligomeric complex formation with the tetrameric form the most prominent oligomer. Using different and particularly harsh denaturing conditions we found that the observed oligomeric aggregates persisted, indicating highly stable complexes. The most prominent tetrameric aggregate was identified to be cytochrome b5 by mass spectrometric sequencing. Further complex formation studies, using a fluorescent dye (1-anilinonaphthalene-8-sulfonic acid) that interact with hydrophobic cavities formed during oligomerisation, provided evidence of protein assembly in oligomeric complexes or aggregation. The formation of the cytochrome b5 complexes was dependent on ionic strength and protein concentration. Previously it was shown that the hydrophobic membrane anchoring domain plays a pivotal role in the cytochrome b5’s homomeric complexes. Using a peptide (IITTIDSNSS), resembling a portion of this domain, together with circular dichroism we showed more organized structure present for the wildtype peptide vs. a mutated control peptide (LLSSLKAVAV). A modified ELISA interaction assay also revealed that the wild-type peptide had a specific interaction with cytochrome b5, providing further evidence that the membrane anchoring domain plays a role in complex formation. These studies also indicated that a hydrogen bond network in this domain may be important for the formation of the homomeric complexes of cytochrome b5.
AFRIKAANSE OPSOMMING: Membraan-gebonde sitochroom b5 is ’n alomteenwoordige proteïen met ’n gemiddelde molekulêre massa van 16 kDa. Die proteïen is betrokke in reaksies waar dit elektrone direk aan sitochroom P450 ensieme verskaf, sowel as ensieme betrokke in lipiedbiosintese. Dit is ook bekend dat die proteïen die aktiwiteite van sekere ensieme via ’n allosteriese effek beïnvloed. Dit is geredelik in die literatuur aanvaar dat sitochroom b5 as ’n monomeer voorkom, maar daar is kort gelede gerapporteer dat homomeriese komplekse in vivo vorm. In hierdie studie is die sitochroom b5-kompleksvorming ondersoek deur gebruik te maak van verskeie analietiese metodes. Sitochroom b5 is vanuit skaaplewer mikrosome geïsoleer en die suiwerheid met behulp van natrium-dodesiel-sulfaat-poliakrielamied-gel-elektroforese en elektrosproei-ionisasie massa-spektrometrie geverifieer. Met die laasgenoemde bevestig dat ’n enkele heem-bevattende proteïen met Mr =15865 teenwoordig was, terwyl poliakrielamied gel-skeiding kompleksvorming getoon het, met tetrameer as die mees prominente oligomeer. Deur verskeie denaturerings kondisies, intsluitend besondere kondisies, is gevind dat hierdie aggregate behoue bly, wat baie stabiele oligomere aandui. Die mees prominente tetrameriese aggregaat is as sitochroom b5 geïdentifiseer met behulp van massa spektrometriese volgordebepaling. Kompleksvorming is verder bewys deur ’n verdere ondersoek met behulp van ’n fluoresserende kleurstof (1-anilinonaftaleen-8-sulfoonsuur) wat met die hirdofobiese holtes, wat vorm tydens oligomermerisasie, interaksie het. Die kompleksvorming was afhanklik van ioniese sterkte, sowel as proteïenkonsentrasie. Voorheen was dit bewys dat die deurslaggewende faktor in die vorming sitochroom b5 se homomeriese komplekse die hidrofobiese membraan-anker-domein is. Deur gebruik te maak van ’n peptied (IITTIDSNSS) wat lyk soos ’n gedeelte van hierdie domein, tesame met sirkulêre dichroisme, is gewys dat meer georganiseerde struktuur teenwoordig was vir die wilde tipe peptied vs. ’n gemuteerde kontrole peptied (LLSSLKAVAV). ’n Gemodifiseerde ELISAinteraksie- essai het ook getoon dat die wilde-tipe peptied spesifieke interaksie met sitochroom b5 het, ’n verdere bewys dat hierdie membraan-anker-domein ’n rol speel in kompleksvorming. Hierdie studies het ook aangedui dat ’n waterstofbinding netwerk in die domein belangrik kan wees vir die vorming van die homomeriese komplekse van sitochroom b5.
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Sun, Bingyun. "Spatially and temporally resolved delivery of stimuli to single cells using nanocapsules and laser manipulation /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/8544.
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Almeida, JoÃo Paulo Nobre de. "Germination and seedling growth of amburana cearensis (AllemÃo) A.C. smith as a function the weight of seeds and abiotic factors." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13207.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoGiven the needs of reclamation is increasing interest in the propagation of native species, which requires basic information about their germination characteristics and ecophysiological. The Amburana cearensis (AllemÃo) A.C. Smith known as cumaru is a species widely used for restoration of the landscape. The aim of this study was to investigate the germination and seedling growth of cumaru depending on the weight of the seeds under conditions of light, temperature, drought stress, as well as to determine the seed imbibition curve, internal morphology, chemical composition and quantification of the coumarin. Initially seeds were individually weighed and separated into three weight classes (light, medium and heavy), these being submitted to the determination of water content, thousand seeds weight and germination tests in two light conditions (presence and absence ) and six schemes temperatures (20, 25, 30, 35, 40, and 20-30 ÂC). In addition to these tests, it was determined the imbibition curve of each weight class and made assessment of drought stress tolerance under different potentials(-0.2, -0.4, -0.6, -0.8 and -1,0 MPa). The experiments were arranged in a completely randomized design in four replications for each treatment. For the internal morphology of seeds were used in cytochemistry usual techniques for the identification of the main structures and substances reserves. To visualize the coumarin in the seeds by NMR spectroscopy was used. The optimum conditions for seed germination occurred at 30 ÂC, which are insensitive to light and vigor seeds for light and medium. The best conditions for seedling growth occurred with the light and medium seeds at 25 and 30 ÂC and in the presence of light, with temperatures of 35 and 40 ÂC harmful. Light and medium seeds showed the same pattern of water absorption, while not reach the heavy phase III of the curve. The decrease in the water potential of the substrate affect the germination and growth of seedlings from seed medium and heavy compared to the light, and from -0.6 MPa in a condition strictly limiting seedling development. The chemical constituents present in the seeds of A. cearensis are quantitatively different depending on the weight of the seeds, and the heavy characterized by a high content of lipids. The NMR spectroscopy falls greater proportion of coumarin in seed extract heavy and medium, possibly affecting ecophysiological needs of the species A. cearensis.
Diante das necessidades de recuperaÃÃo de Ãreas degradadas à crescente o interesse na propagaÃÃo de espÃcies florestais nativas, o que demanda informaÃÃes bÃsicas sobre as suas caracterÃsticas germinativas e ecofisiolÃgicas. A Amburana cearensis (AllemÃo) A.C. Smith conhecida como cumaru à uma espÃcie bastante utilizada para recomposiÃÃo da paisagem. O objetivo deste trabalho foi estudar a germinaÃÃo e o crescimento de plÃntulas de cumaru em funÃÃo do peso das sementes sob diferentes condiÃÃes de temperatura, luz, estresse hÃdrico, bem como determinar nas sementes a curva de embebiÃÃo, morfologia interna, composiÃÃo quÃmica e identificaÃÃo da cumarina. Inicialmente as sementes foram pesadas individualmente e separadas em trÃs classes de peso (leves, mÃdias e pesadas), sendo estas, submetidas à determinaÃÃo dos teores de Ãgua, peso de mil de sementes e a testes de germinaÃÃo em duas condiÃÃes de luz (presenÃa e ausÃncia) e seis regimes de temperatura (20, 25, 30, 35, 40 e 20-30ÂC). AlÃm destes ensaios, foi determinado a curva de embebiÃÃo de cada classe de peso e avaliaÃÃo da tolerÃncia ao estresse hÃdrico sob diferentes potenciais (-0,2, -0,4, -0,6, -0,8 e -1,0 MPa). Os experimentos foram dispostos em delineamento inteiramente casualizado com quatro repetiÃÃes para cada tratamento. Para a morfologia interna das sementes foram utilizadas tÃcnicas usuais em citoquÃmica para a identificaÃÃo das principais estruturas e substÃncias de reservas. Para a visualizaÃÃo da cumarina nas sementes foi utilizada a espectroscopia por RMN. As condiÃÃes Ãtimas para a germinaÃÃo das sementes ocorreu na temperatura de 30ÂC, sendo estas insensÃveis à luz e um maior vigor para sementes leves e mÃdias. As melhores condiÃÃes para o crescimento das plÃntulas ocorreram com as sementes leves e mÃdias nas temperaturas de 25 e 30ÂC e na presenÃa de luz, sendo as temperaturas de 35 e 40 ÂC prejudiciais. Sementes leves e mÃdias apresentam o mesmo padrÃo de absorÃÃo de Ãgua, enquanto as pesadas nÃo atingem a fase III da curva. O decrÃscimo do potencial hÃdrico do substrato prejudica a germinaÃÃo e o crescimento de plÃntulas oriundas de sementes mÃdias e pesadas em comparaÃÃo Ãs leves, sendo a partir de -0,6 MPa uma condiÃÃo estritamente limitante na formaÃÃo de plÃntulas. Os constituintes quÃmicos presentes nas sementes de A. cearensis sÃo quantitativamente diferenciados em funÃÃo do peso das sementes, sendo as pesadas caracterizadas por um elevado teor de lipÃdios. A espectroscopia por RMN releva uma maior proporÃÃo de cumarina no extrato de sementes pesadas e mÃdias, que possivelmente afetam as necessidades ecofisiolÃgicas da espÃcie A. cearensis.
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Zhang, Zhiling. "The structure and function of troponin T upon metal ion binding and the detection of nucleic acid sequence variations." Thesis, University of North Texas, 2005. https://digital.library.unt.edu/ark:/67531/metadc5565/.
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Numerous troponin T (TnT) isoforms are generated by alternative RNA splicing primarily in its NH2-terminal hypervariable region, but the functions of these isoforms are not completely understood. In this dissertation work, calcium and terbium binding behavior of several forms of TnT were investigated by spectroscopic and radioactive techniques. Chicken breast muscle TnT binds calcium and terbium through its NH2-terminal Tx motif (HEEAH)n with high affinity (10-6 mM) and fast on-rate (106 - 107 M-1 s-1). Chicken leg muscle TnT and a human cardiac TnT NH2-terminal fragment, which both lack the Tx motif on their NH2-terminal regions, do not have affinities for calcium in the physiological range. Computational predictions on TnT N47 suggest that the TnT NH2-terminal region might fold into an elongated structure with at least one high affinity metal ion binding pocket comprised primarily of the Tx motif sequence and several lower affinity binding sites. In addition, calcium binding to TnT N47 might alter its conformation and flexibility. Luminescence resonance energy transfer measurements and other experimental observations are consistent with the computational predictions suggesting the computational simulated atomic model is reasonable. TnT mutations are responsible for 15% of familiar hypertrophic cardiomyopathy (FHC) cases with a phenotype of relatively mild hypertrophy, but a high incidence of sudden death. Detection of those genetic mutations would facilitate the clinical diagnosis and initiation of treatment at an early stage. This dissertation also investigated a novel hybridization proximity assay (HYPA) combining molecular beacon and luminescence resonance energy transfer (LRET) technologies. Experimental results suggest that a shared stem probe design produces a more consistent response upon hybridization, whereas the internally labeled probe was less consistent, but can yield the highest responses. Using the optimally designed molecular probes, the HYPA provides a detection of alterations in nucleic acid structure of as little as a single nucleotide. This novel HYPA is expected to expand its applications in the analysis and screening of genetic diseases.
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Roberts, Juliet A. "Evaluation of the quantitative cytochemistry of glutathione, oxidative enzymes of the pentose phosphate pathway and related systems for the functional characterisation of malignant cells." Thesis, Brunel University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278886.
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Santos, Marcio Quara de Carvalho. "Propriedades do sangue e efeito do mergulho forçado sobre o perfil hematológico de Podocnemis erythrocephala (Spix, 1824) (Testudines, Podocnemididae) do Médio Rio Negro, Amazonas." Universidade Federal do Amazonas, 2011. http://tede.ufam.edu.br/handle/tede/4595.
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FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas
Irapuca, Podocnemis erythrocephala, is the poorly studied turtle species among the Amazonian Podocnemis and suffers from large predatory pressure by the human population, causing a decline in their natural stocks. This study aimed to determine the hematological parameters, the morphological and cytochemical features of blood cells, as well as the effect of forced diving on the blood profile of P. erythrocephala, generating relevant information to the proposition of management plans and conservation strategies for this species. Analysis revealed that sex exercised little influence on the blood profile of the animals, unlike the growth. It was found that hatchlings showed lower eritrogram than immature and mature animals, unlike the concentrations of glucose and total cholesterol that were higher, confirming the high metabolic rate of hatchlings. Overall, the changes found in blood parameters reflected changes in physiological function of the behavior and natural history of the species. Due the effect of sex and development phase on the blood parameters, reference ranges were established for hatchlings, immature males, mature males, immature females and mature females. From the morphological analysis of blood cells from irapuca erythrocytes, thrombocytes, lymphocytes, azurophilic, heterophils, eosinophils and basophils were identified with morphological characteristics similar to those described for other Podocnemidid species. Cytochemical analysis indicated that heterophils, eosinophils and basophils are the most active cells of the immune system of this species, being primarily responsible for phagocytic activity due the presence of glycogen, lipid and peroxidase. No changes were observed on the eritrogram of animals subjected to 30 and 60 minutes of forced submersion. Increased levels of plasma lactate, calcium and magnesium, according to the dive time, reflected physiological adjustments to maintain the acid-base balance, whereas changes in the levels of total cholesterol and triglycerides indicated that during anoxia, the irapuca activated the ATP production from lipid catabolism, as a complementary way to anaerobic glycolysis. The irapuca proved to be a tolerant species to 60 minutes of forced diving, although higher periods might cause metabolic acidosis and depletion of energy substrates. These values constitute a basis for assessing the health status of wild irapucas.
A irapuca, Podocnemis erythrocephala, é a espécie menos estudada entre os podocnemidídeos amazônicos e vem sofrendo grande pressão antrópica, que tem contribuído para o declínio de seus estoques naturais. Este trabalho teve como objetivo determinar os parâmetros hematológicos, as características morfológicas e citoquímicas das células do sangue, bem como o efeito do mergulho forçado sobre o perfil sanguíneo de P. erythrocephala, gerando informações relevantes para a elaboração de planos de manejo e estratégias de conservação para a espécie. As análises revelaram que o sexo exerceu menor influência sobre o perfil hematológico dos animais, diferentemente do crescimento. Foi verificado que espécimes recém-eclodidos apresentaram valores do eritrograma inferiores em relação aos animais imaturos e maduros, ao contrário das concentrações de glicose e colesterol total, que foram superiores, confirmando a alta demanda metabólica que os recém-eclodidos possuem. De forma geral, as alterações encontradas nos parâmetros sanguíneos refletiram adaptações fisiológicas em função do comportamento e da história natural da espécie. Em função do efeito do sexo e da fase de crescimento sobre os parâmetros sanguíneos, foram estabelecidos intervalos de referência para recém-eclodidos, machos imaturos, machos maduros, fêmeas imaturas e fêmeas maduras. A partir da análise morfológica das células sanguíneas da irapuca, foram identificados eritrócitos, trombócitos, linfócitos, azurófilos, heterófilos, eosinófilos e basófilos com características morfológicas semelhantes às descritas para outros podocnemidídeos. As análises dos constituintes citoquímicos indicaram que os heterófilos, eosinófilos e basófilos são as células mais ativas do sistema imunológico nesta espécie, sendo responsáveis principalmente pela atividade fagocítica, devido a presença de glicogênio, lipídeos e peroxidase. Não foram observadas alterações no eritrograma dos animais submetidos a 30 e 60 minutos de submersão forçada. O aumento nos níveis plasmáticos de lactato, cálcio e magnésio, em função do tempo de mergulho, refletiram ajustes fisiológicos para a manutenção do equilíbrio ácido-base, enquanto que as alterações nos níveis de triglicerídeos e colesterol total indicam que, em situações de anóxia, a irapuca ativa o catabolismo lipídico para a produção de ATP, de forma complementar à glicólise anaeróbica. A irapuca demonstrou ser uma espécie resistente à 60 minutos de mergulho forçado, entretanto períodos superiores podem causar acidose metabólica e exaustão dos substratos energéticos. As informações geradas no presente estudo servirão de base para a avaliação do estado de saúde desta espécie de quelônio amazônico.
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Rego, Letícia do Nascimento Andrade de Almeida. "Espermatogênese de Zaprionus indianus e Zaprionus sepsoides (Diptera: Drosophilidae) : caracterização citoquímica, estrutural e ultraestrutural /." São José do Rio Preto : [s.n.], 2012. http://hdl.handle.net/11449/102760.
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Orientador: Lilian Madi-RavazziCoorientador: Maria Tercília Vilela de Azeredo-Oliveira
Banca: Blanche Christine Pires de Bitner-Mathé Leal
Banca: Maria Izabel Camargo Mathias
Banca: Hermione Elly Melara de Campos Bicudo
Banca: Patrícia Vilamaior
Resumo: Zaprionus indianus é um drosofilídeo nativo da região Afrotropical que colonizou o continente Sul Americano, apresentando uma ampla distribuição geográfica enquanto Z. sepsoides é restrita a algumas regiões africanas. As duas espécies diferem em relação ao tamanho dos testículos e dos espermatozoides que é maior em Z. indianus do que em Z. sepsoides. Com o intuito de conhecer aspectos da biologia e o grau de diferenciação destas espécies, o presente estudo avaliou a espermatogênese de machos de diferentes idades (1, 3, 5 e 8 dias) de ambas as espécies por meio de técnicas de coloração convencional e de ultraestrutura. A espermatogênese e ultraestrutura dos espermatozoides foram semelhantes nas espécies em que foi confirmado o número diploide de cromossomos com 2n = 12. Entretanto, foi observada uma quantidade maior de espermatozoides em machos jovens (1 a 3 dias de idade) em Z. indianus do que em Z. sepsoides, o qual apresentou maior frequência de estágios iniciais da espermatogênese nestas idades. A porção da cabeça dos espermatozoides foi fortemente marcada nas duas espécies pela coloração por prata (AgNOR), orceína lacto-acética e pela reação de Feulgen. Quando submetidos à reação de P.A.S., os testículos de Z. sepsoides e Z. indianus apresentaram grânulos de glicogênio. As espécies possuem a mesma ultraestrutura flagelar, em que o axonema mostra um arranjo de 9+9+2 microtúbulos, com a presença de dois derivados mitocondriais de diferentes tamanhos e o número de 64 espermatozoides por feixe, em ambas as espécies. A grande semelhança observada no padrão do arranjo de microtúbulos do axonema e nos derivados mitocondriais com diferentes tamanhos nas espécies de Zaprionus, comparadas com outras espécies de Drosophila, é indicativa da conservação destas estruturas na família Drosophilidae... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Zaprionus indianus is a drosophilid native to the Afrotropical region that has colonized South America. Z. indianus exhibits a wide geographical distribution, whereas Z. sepsoides is restricted to certain African regions. The two species differ in the size of their testes, which are larger in Z. indianus than in Z. sepsoides. To better understand the biology and the degree of differentiation of these species, the current study evaluated spermatogenesis in males of different ages (1, 3, 5 and 8 days old) from both species by conventional staining techniques and ultrastructural analysis. Spermatogenesis and the ultrastructure of spermatozoa were similar in the two species, for which the diploid number was confirmed to be 2n = 12 chromosomes. However, a greater number of spermatozoa were observed in young Z. indianus males (1-3 days old) than in young Z. sepsoides males, which showed a higher frequency of cells at the early stages of spermatogenesis at this age. A portion of the head of the sperm was strongly marked in both species by silver staining (AgNOR), lacto-acetic orcein and the Feulgen reaction. Additionally, when submitted to P.A.S. reaction, the testes of both Z. sepsoides and Z. indianus exhibited glycogen granules. The two species also presented the same flagellar ultrastructure, in which the axoneme includes a 9+9+2 arrangement of microtubules, two mitochondrial derivatives of different sizes are present and the number of spermatozoa per bundle is 64. The great similarity in the pattern of microtubule arrangement in the axoneme and in the mitochondrial derivatives of the species Zaprionus, as compared with other species of Drosophila, indicates that these structures are preserved in the family Drosophilidae. The differences observed between the young males of Z. indianus and Z. sepsoides, including the number and frequency of sperm... (Complete abstract click electronic access below)
Doutor
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Coffee, Castro-Zena Pilar G. "Hindrance of the Myosin Power Stroke Posed by the Proximity to the Troponin Complex Identified Using a Novel LRET Fluorescent Nanocircuit." Thesis, University of North Texas, 2007. https://digital.library.unt.edu/ark:/67531/metadc3688/.
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A novel luminescence resonance energy transfer (LRET) nanocircuit assay involving a donor and two acceptors in tandem was developed to study the dynamic interaction of skeletal muscle contraction proteins. The donor transmits energy relayed to the acceptors distinguishing myosin subfragment-1 (S1) lever arm orientations. The last acceptor allows the detection of S1's bound near or in between troponin complexes on the thin filament. Additionally, calcium related changes between troponin T and myosin were detected. Based on this data, the troponin complex situated every 7 actin monomers, hinders adjacently bound myosins to complete their power stroke; whereas myosins bound in between troponin complexes undergo complete power strokes.
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Rego, Letícia do Nascimento Andrade de Almeida [UNESP]. "Espermatogênese de Zaprionus indianus e Zaprionus sepsoides (Diptera: Drosophilidae): caracterização citoquímica, estrutural e ultraestrutural." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/102760.
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rego_lnaa_dr_sjrp.pdf: 4366458 bytes, checksum: 268d79cfb562ff5fb2f7391289c1b934 (MD5)Zaprionus indianus é um drosofilídeo nativo da região Afrotropical que colonizou o continente Sul Americano, apresentando uma ampla distribuição geográfica enquanto Z. sepsoides é restrita a algumas regiões africanas. As duas espécies diferem em relação ao tamanho dos testículos e dos espermatozoides que é maior em Z. indianus do que em Z. sepsoides. Com o intuito de conhecer aspectos da biologia e o grau de diferenciação destas espécies, o presente estudo avaliou a espermatogênese de machos de diferentes idades (1, 3, 5 e 8 dias) de ambas as espécies por meio de técnicas de coloração convencional e de ultraestrutura. A espermatogênese e ultraestrutura dos espermatozoides foram semelhantes nas espécies em que foi confirmado o número diploide de cromossomos com 2n = 12. Entretanto, foi observada uma quantidade maior de espermatozoides em machos jovens (1 a 3 dias de idade) em Z. indianus do que em Z. sepsoides, o qual apresentou maior frequência de estágios iniciais da espermatogênese nestas idades. A porção da cabeça dos espermatozoides foi fortemente marcada nas duas espécies pela coloração por prata (AgNOR), orceína lacto-acética e pela reação de Feulgen. Quando submetidos à reação de P.A.S., os testículos de Z. sepsoides e Z. indianus apresentaram grânulos de glicogênio. As espécies possuem a mesma ultraestrutura flagelar, em que o axonema mostra um arranjo de 9+9+2 microtúbulos, com a presença de dois derivados mitocondriais de diferentes tamanhos e o número de 64 espermatozoides por feixe, em ambas as espécies. A grande semelhança observada no padrão do arranjo de microtúbulos do axonema e nos derivados mitocondriais com diferentes tamanhos nas espécies de Zaprionus, comparadas com outras espécies de Drosophila, é indicativa da conservação destas estruturas na família Drosophilidae...
Zaprionus indianus is a drosophilid native to the Afrotropical region that has colonized South America. Z. indianus exhibits a wide geographical distribution, whereas Z. sepsoides is restricted to certain African regions. The two species differ in the size of their testes, which are larger in Z. indianus than in Z. sepsoides. To better understand the biology and the degree of differentiation of these species, the current study evaluated spermatogenesis in males of different ages (1, 3, 5 and 8 days old) from both species by conventional staining techniques and ultrastructural analysis. Spermatogenesis and the ultrastructure of spermatozoa were similar in the two species, for which the diploid number was confirmed to be 2n = 12 chromosomes. However, a greater number of spermatozoa were observed in young Z. indianus males (1-3 days old) than in young Z. sepsoides males, which showed a higher frequency of cells at the early stages of spermatogenesis at this age. A portion of the head of the sperm was strongly marked in both species by silver staining (AgNOR), lacto-acetic orcein and the Feulgen reaction. Additionally, when submitted to P.A.S. reaction, the testes of both Z. sepsoides and Z. indianus exhibited glycogen granules. The two species also presented the same flagellar ultrastructure, in which the axoneme includes a 9+9+2 arrangement of microtubules, two mitochondrial derivatives of different sizes are present and the number of spermatozoa per bundle is 64. The great similarity in the pattern of microtubule arrangement in the axoneme and in the mitochondrial derivatives of the species Zaprionus, as compared with other species of Drosophila, indicates that these structures are preserved in the family Drosophilidae. The differences observed between the young males of Z. indianus and Z. sepsoides, including the number and frequency of sperm... (Complete abstract click electronic access below)
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Patel, Dipesh A. "Luminescence Resonance Energy Transfer-Based Modeling of Troponin in the Presence of Myosin and Troponin/Tropomyosin Defining Myosin Binding Target Zones in the Reconstituted Thin Filament." Thesis, University of North Texas, 2009. https://digital.library.unt.edu/ark:/67531/metadc9834/.
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Mechanistic details on the regulation of striated muscle contraction still need to be determined, particularly the specific structural locations of the elements comprising the thick and thin filaments. Of special interest is the location of the regulatory component, troponin, on the actin filament and how its presence influences the behavior of myosin binding to the thin filament. In the present study: (1) Luminescence resonance energy transfer was used to monitor potential conformational changes in the reconstituted thin filament between the C-terminal region of troponin T and myosin subfragment 1; (2) Location of troponin in previously derived atomic models of the acto-myosin complex was mapped to visualize specific contacts; and (3) Shortened tropomyosin was engineered and protein binding and ATPase assays were performed to study the effect of myosin binding close to the troponin complex. Analysis of the results suggest the following: (1) Irrespective of calcium levels, the C-terminal region of troponin T is located close to myosin loop 3 and a few actin helices that may perturb strong acto-myosin interactions responsible for force production. (2) Atomic models indicate myosin subfragment 1 cannot attain the post- powerstroke state due to the full motion of the lever arm being sterically hindered by troponin. (3) A shortened tropomyosin with five actin binding modules (instead of the native seven in muscle cells) binds actin contiguously in a head-to-tail manner and serves to increase the periodicity of troponin complexes on the actin filament. Such behavior eliminates the structure of the actin filament being responsible for the binding location of tropomyosin. (4) Differential behavior of myosin subfragment 1 i.e. (a) binding adjacent to troponin and (b) binding further away from troponin, is apparent as tropomyosin and troponin appear to govern the regions or "target zones" where myosin can bind productively along the actin filament. Physiologically, myosins able to bind close to troponin, but not participate in force production may function as mechanical sensors to attenuate or dampen the force generated from the so-called "target zones". Therefore, this could be a pseudo-regulatory mechanism that functions to protect the contractile apparatus from damage.
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Zanotti, Luciana Carla Rameh-de-Albuquerque. "Aspectos hematológicos, bioquímicos, morfológicos e citoquímicos de células sangüíneas em Viperídeos neotropicais dos gêneros Bothrops e Crotalus mantidos em cativeiro." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/10/10133/tde-31052007-143116/.
Full textAbstract:
Este estudo apresenta um painel de dados hematológicos, bioquímicos, morfológicos e citoquímicos para um grupo de serpentes dos gêneros Bothrops e Crotalus mantidas em cativeiro no Instituto Butantan. Para tanto, amostras de sangue foram colhidas da veia coccígea ventral e processadas de acordo com métodos padronizados. Os resultados alcançados foram analisados para determinar diferenças interespecíficas e sexuais. A avaliação citoquímica incluiu Sudan Black B (SBB), Ácido Periódico de Schiff (PAS) e Benzidina Peroxidase (BP). Os resultados hematológicos e bioquímicos mais relevantes indicaram um número significativamente mais alto de basófilos em B. jararaca e níveis mais altos de cálcio nas fêmeas da maioria das espécies. Os azurófilos marcaram positivamente para todas as colorações. A diferenciação entre trombócitos e linfócitos foi facilmente obtida com PAS. Os basófilos marcaram positivamente apenas com PAS em Bothrops alternatus. A marcação em heterófilos variou consideravelmente entre as espécies. Ultra-estruturalmente, os leucócitos foram semelhantes ao já descrito em literatura com algumas variações no tipo dos grânulos dos basófilos e heterófilos. Os grânulos dos basófilos apresentaram-se redondos em sua maioria, com tamanho e densidade variadas, enquanto que os nos heterófilos foram heterogêneos em forma, tamanho e densidade.This study reports a panel for hematological, biochemical, morphological and cytochemical data for a group of captive snakes belonging to the genus Bothrops and Crotalus mantained at Instituto Butantan, São Paulo, Brazil. Blood samples were collected from ventral coccigeal vein and were processed according to standard protocols. Cytochemical staining including Sudan Black B (SBB), Periodic Acid-Schiff (PAS) and Benzidine peroxidase (BP) were conducted. Blood values were evaluated to determine interspecific and sex differences. We found a significant increase of basophils in Bothrops jararaca and higher levels of calcium in females. Azurophils stained positively for all stains and a differentiation between lymphocytes and thrombocytes was easily obtained with PAS stain. Basophils stained positively only with PAS in Bothrops alternatus. Heterophils staining varied between species. The ultrastructure of leucocytes were similar within described in literature, with some variations on granules of basophils and heterophils. Basophils granules were round, with heterogeneous size and density; whereas, heterphils granules were heterogeneous in shape, size and density.
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Almeida, João Paulo Nobre de. "Germinação e crescimento de plântulas de amburana cearensis (Allemão) A.C. smith em função do peso de sementes e fatores abióticos." reponame:Repositório Institucional da UFC, 2014. http://www.repositorio.ufc.br/handle/riufc/16828.
Full textAbstract:
ALMEIDA, João Paulo Nobre de. Germinação e crescimento de plântulas de amburana cearensis (Allemão) A.C. smith em função do peso de sementes e fatores abióticos. 2014. 109 f. : Dissertação (mestrado) - Universidade Federal do Ceará, centro de Ciências Agrárias, Departamento de Fitotecnia, Curso de Pós-Graduação em Agronomia / Fitotecnia, Fortaleza-CE, 2014Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-05-17T12:18:57Z No. of bitstreams: 1 2014_dis_jpnalmeida.pdf: 1353578 bytes, checksum: cba2917425c9a0dbf90e35a88352f7ff (MD5)
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Given the needs of reclamation is increasing interest in the propagation of native species, which requires basic information about their germination characteristics and ecophysiological. The Amburana cearensis (Allemão) A.C. Smith known as cumaru is a species widely used for restoration of the landscape. The aim of this study was to investigate the germination and seedling growth of cumaru depending on the weight of the seeds under conditions of light, temperature, drought stress, as well as to determine the seed imbibition curve, internal morphology, chemical composition and quantification of the coumarin. Initially seeds were individually weighed and separated into three weight classes (light, medium and heavy), these being submitted to the determination of water content, thousand seeds weight and germination tests in two light conditions (presence and absence ) and six schemes temperatures (20, 25, 30, 35, 40, and 20-30 °C). In addition to these tests, it was determined the imbibition curve of each weight class and made assessment of drought stress tolerance under different potentials(-0.2, -0.4, -0.6, -0.8 and -1,0 MPa). The experiments were arranged in a completely randomized design in four replications for each treatment. For the internal morphology of seeds were used in cytochemistry usual techniques for the identification of the main structures and substances reserves. To visualize the coumarin in the seeds by NMR spectroscopy was used. The optimum conditions for seed germination occurred at 30 °C, which are insensitive to light and vigor seeds for light and medium. The best conditions for seedling growth occurred with the light and medium seeds at 25 and 30 °C and in the presence of light, with temperatures of 35 and 40 °C harmful. Light and medium seeds showed the same pattern of water absorption, while not reach the heavy phase III of the curve. The decrease in the water potential of the substrate affect the germination and growth of seedlings from seed medium and heavy compared to the light, and from -0.6 MPa in a condition strictly limiting seedling development. The chemical constituents present in the seeds of A. cearensis are quantitatively different depending on the weight of the seeds, and the heavy characterized by a high content of lipids. The NMR spectroscopy falls greater proportion of coumarin in seed extract heavy and medium, possibly affecting ecophysiological needs of the species A. cearensis.
Diante das necessidades de recuperação de áreas degradadas é crescente o interesse na propagação de espécies florestais nativas, o que demanda informações básicas sobre as suas características germinativas e ecofisiológicas. A Amburana cearensis (Allemão) A.C. Smith conhecida como cumaru é uma espécie bastante utilizada para recomposição da paisagem. O objetivo deste trabalho foi estudar a germinação e o crescimento de plântulas de cumaru em função do peso das sementes sob diferentes condições de temperatura, luz, estresse hídrico, bem como determinar nas sementes a curva de embebição, morfologia interna, composição química e identificação da cumarina. Inicialmente as sementes foram pesadas individualmente e separadas em três classes de peso (leves, médias e pesadas), sendo estas, submetidas à determinação dos teores de água, peso de mil de sementes e a testes de germinação em duas condições de luz (presença e ausência) e seis regimes de temperatura (20, 25, 30, 35, 40 e 20-30°C). Além destes ensaios, foi determinado a curva de embebição de cada classe de peso e avaliação da tolerância ao estresse hídrico sob diferentes potenciais (-0,2, -0,4, -0,6, -0,8 e -1,0 MPa). Os experimentos foram dispostos em delineamento inteiramente casualizado com quatro repetições para cada tratamento. Para a morfologia interna das sementes foram utilizadas técnicas usuais em citoquímica para a identificação das principais estruturas e substâncias de reservas. Para a visualização da cumarina nas sementes foi utilizada a espectroscopia por RMN. As condições ótimas para a germinação das sementes ocorreu na temperatura de 30°C, sendo estas insensíveis à luz e um maior vigor para sementes leves e médias. As melhores condições para o crescimento das plântulas ocorreram com as sementes leves e médias nas temperaturas de 25 e 30°C e na presença de luz, sendo as temperaturas de 35 e 40 °C prejudiciais. Sementes leves e médias apresentam o mesmo padrão de absorção de água, enquanto as pesadas não atingem a fase III da curva. O decréscimo do potencial hídrico do substrato prejudica a germinação e o crescimento de plântulas oriundas de sementes médias e pesadas em comparação às leves, sendo a partir de -0,6 MPa uma condição estritamente limitante na formação de plântulas. Os constituintes químicos presentes nas sementes de A. cearensis são quantitativamente diferenciados em função do peso das sementes, sendo as pesadas caracterizadas por um elevado teor de lipídios. A espectroscopia por RMN releva uma maior proporção de cumarina no extrato de sementes pesadas e médias, que possivelmente afetam as necessidades ecofisiológicas da espécie A. cearensis.
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Böttcher, Denny. "Morphologisch-funktionelle Charakterisierung equiner endometrialer Epithel- und Stromazellen in Monokultur unter Einbeziehung immunzytologischer und transmissionselektronenmikroskopischer Methoden." Doctoral thesis, Universitätsbibliothek Leipzig, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-77749.
Full textAbstract:
Ziel der vorliegenden Arbeit war die morphologische und funktionelle Charakterisierung endometrialer Epithel- (EEZ) und Stromazellen (ESZ) des Pferdes bei separater Primärkultur auf permeablen Kunststoffoberflächen mit Hilfe (immun-)zytologischer, zytochemischer und transmissionselektronenmikroskopischer Untersuchungen, ein-schließlich einer vergleichenden Betrachtung der immunhistologischen und histochemischen Eigenschaften der Epithel- und Stromazellen in situ. Mögliche Zusammenhänge zwischen der endometrialen Funktionsmorphologie zum Zeitpunkt der Zellisolierung und den Zelleigenschaften in vitro sollten überprüft werden.
Zur Zellgewinnung dienten transzervikal entnommene Endometriumbioptate (n = 14) sowie vollständige Uteri euthanasierter Stuten (n = 6). Parallel entnommene Gewebeproben wurden fixiert und als In-situ-Vergleichsmaterial verwendet. Nach einer mechanischen und enzymatischen Gewebedissoziation erfolgte die Trennung von Epithel- und Stromazellen mittels Filtration, Dichtegradientenzentrifugation sowie Differenzialadhärenz. Ein Teil der aufgereinigten Zellen wurde Formalin-fixiert und für (immun-)zytologische und zytochemische Untersuchungen, insbesondere hinsichtlich des Separationserfolges, aufbereitet. Die Kultivierung der übrigen Zellen beider Zellarten fand separat voneinander auf unbeschichteten Membraneinsätzen (Millicell® PET) in einem Gemisch aus DMEM und Ham’s F-12 unter Zusatz von 10 % fötalem Kälberserum (ESZ bis ca. 60 % Konfluenz) bzw. unter Zusatz von 2,5 % fötalem Kälberserum sowie verschiedener Additive (ESZ ab ca. 60 % Konfluenz sowie EEZ) bei 37 °C in wasserdampfgesättigter, mit 5 % CO2 angereicherter Raumluft statt. Konfluente Kulturen wurden in Formalin bzw. Glutaraldehyd fixiert und für die Lichtmikroskopie respektive Transmissionselektronenmikroskopie aufgearbeitet.
Zum Zeitpunkt der Zellisolierung befanden sich die Endometrien überwiegend in der Phase der physiologischen Inaktivität (n = 5) oder der regulären zyklischen sekretorischen (n = 8) bzw. proliferativen (n = 3) Aktivität. In jeweils einer der Gewebeproben war eine irreguläre sekretorische, eine irreguläre proliferative bzw. eine im Übergang zwischen Sekretion und Proliferation anzusiedelnde Funktionsmorphologie festzustellen. In einem weiteren Fall wurden die Zellen aus einem graviden Uterus isoliert.
Die Separation von ESZ während des Winteranöstrus verlief mit unzureichendem Erfolg, die Kulturen zeigten eine starke Kontamination mit epithelialen Zellen.
Die morphologischen, immunzytologischen und zytochemischen Eigenschaften der beiden separierten Zellpopulationen unmittelbar vor Beginn der Kultivierung ermöglichten keine eindeutige Unterscheidung zwischen Epithel- und Stromazellen.
Bei den aus sekretorisch differenzierten Endometrien isolierten ESZ war die Zeitdauer bis zum Erreichen der Konfluenz tendenziell länger als bei Verwendung proliferativ differenzierter Endometrien, während bei den EEZ diesbezüglich keine deutlichen Unterschiede erkennbar waren. Zum Zeitpunkt der Konfluenz konnten anhand der lichtmikroskopischen Morphologie 4 verschiedene EEZ- und 3 verschiedene ESZ-Typen nachgewiesen werden. Ultrastrukturell war eine Unterscheidung der EEZ von den ESZ möglich, innerhalb dieser beiden Zellpopulationen besaßen die lichtmikroskopisch verschiedenen Zelltypen jedoch jeweils vergleichbare Eigenschaften. Ein Zusammenhang zwischen der In-vitro-Morphologie und dem Zyklusstand zum Zeitpunkt der Zellisolierung war nicht zu erkennen. Unabhängig von der lichtmikroskopischen Morphologie wiesen die EEZ in der Regel laterale Zellverbindungen in Form von tight junctions auf, was auf einen polarisierten Phänotyp schließen lässt.
Der Nachweis von Proteoglykanen mittels Alzianblau-Färbung verlief in allen kultivierten Zellen mit negativem Ergebnis. Mit Hilfe der PAS-Reaktion waren in der Mehrzahl der EEZ sowie in zahlreichen ESZ in vitro Polysaccharide/Glykoproteine nachweisbar. Die kultivierten EEZ exprimierten stets Zytokeratin 19 und in keinem Falle Desmin; in einem Teil der Zellen konnten die Zytokeratine 8 und 18, Vimentin sowie α-Glattmuskel-Aktin nachgewiesen werden. Demgegenüber enthielten die ESZ keines der untersuchten Zytokeratine, zum Teil trat in diesen Zellen jedoch eine Expression von Vimentin, Desmin und α-Glattmuskel-Aktin auf. Insgesamt war ein eindeutiger Nachweis des zellulären Ursprungs equiner endometrialer Epithel- und Stromazellen in vitro ausschließlich anhand der Zytokeratin-19-Expression möglich. Die Eigenschaften der kultivierten EEZ wichen bei der Zellisolierung aus physiologisch inaktiven Endometrien hinsichtlich der PAS-Reaktion sowie des Nachweises von Zytokeratin 8 und Vimentin von denen der aus den aktiven Endometrien gewonnenen Zellen ab. Darüber hinaus wurden keine deutlichen Einflüsse der endometrialen Funktionsmorphologie zum Zeitpunkt der Zellisolierung auf die zytochemischen und immunzytologischen Charakteristika der kultivierten Zellen offensichtlich.
Auf der Grundlage dieser Arbeit können weiterführende Untersuchungen im Zellkulturmodell des equinen Endometriums erfolgen, insbesondere hinsichtlich von Veränderungen der Zelleigenschaften bei Einwirken definierter Milieufaktoren.
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Kanashiro, Claudia. "Análise da dinâmica da origem e destino das células trofoblásticas na interface materno-fetal do útero gestante do cobaio na elucidação da organização da placenta vitelina invertida." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-03042012-171821/.
Full textAbstract:
A implantação embrionária e a placentação em cobaios são caracterizadas pela presença trofoblastos que se destacam da placenta principal, semelhantes ao trofoblasto extra-viloso de humanos. Nestes animais ultrapassam os limites, e podem ser encontrados infiltrados no profundamente no endométrio e no em ambiente externo ultrapassando aos limites da parede uterina. A cobaia desenvolve uma importante estrutura fisiológica de troca materno-embrionária, denominada de placenta vitelina invertida, definidas como membrana fetal destituída parcial ou totalmente do revestimento trofoblástico que permite a exposição do endoderma extra-embrionário em contato direto com o tecido materno. Tais características denotam um mecanismo de controle da resposta imune materna distinta dos paradigmas estabelecidos na reprodução humana e de roedores, assim como ratos e camundongos. Sendo a mais intrigante, a destituição do trofoblasto como célula da interface-materno-fetal que controla a tolerância imune-materna.No presente trabalho, procurou-se estabelecer a organização da placenta vitelina de cobaios a partir da identificação das células que compõe esta membrana extra-embrionária e identificar em que momento ocorre à remoção das células trofoblásticas, e a subseqüente forma de interação das células da placenta vitelina na interface com o tecido materno. Para tanto foram utilizados cobaias fêmeas com idade gestacional conhecida, sacrificadas para coleta de segmentos uterinos nos períodos iniciais da gestação e destinados ao processamento histotógico de embebição em parafina. Na ausência de marcadores celulares específicos conhecidos para cobaios, foram realizados testes prospectivos com reações: citoquímicas de PAS e azul de toluidina (AT; um painel de lectinas biotinadas com afinidade específica para diferentes açúcares; e imunocitoquímica para citoqueratina. As reações realizadas com PAS e AT não identificaram populações celulares com marcação seletiva. Contudo dentre as lectinas tetadas, a Erytrina cristagali lectin (ECL) apresentou reação altamente seletiva para a população de trofoblasto mural (TM) que se origina do trofectoderma, mantendo esta reatividade ao longo da gestação. Esta marcação permitiu avaliar temporal e espacialmente o destino destas células que ao longo da gestação eram mantidas como monocamada de TM revestindo externamente a placenta vitelina e, portanto, não expondo as células do endoderma parietal ou visceral ao ecido materno. Pelo acompanhamento do desenvolvimento embrionário nos cortes seriados, foi constatada no interior do blastocisto a organização de duas massas celulares internas em pólos opostos desde a fase de pré-eclosão. Uma das massas celulares constituída de embrioblastos que dará origem aos os folhetos embrionários nas fases subseqüentes, enquanto a outra formada as células tronco trofoblásticas precursora do cone ectoplacentário (CE). A cavidade da blastocele que separa estas duas massas celulares tem a sua parede revestida pelo endoderma parietal em fase tardia, após a formação da cavidade amniótica. Estes achados demonstram a pecularidade da embriogênese no cobaio, diferente daquelas descritas para humanos e outros roedores, não permitem analogias diretas, o que pode ter contribuído para o equívoco na descrição clássica da organização e constituição da placenta vitelina invertida de constituição córion-amniótica. Isto é, o trofoblasto participa da organização da placenta vitelina inicial e permanece na membrana âmnion-córion-vitelina perfazendo todo o limite do embrião ao longo da gestação. Portanto a hipótese da placenta vitelina parcial ou totalmente invertida baseada na descrição clássica em cobaios é decorrente da interpretação equivocada da embriogênese destes animais.The guinea pig embryo implantation and placentation is characterized by trophoblast cells detaching from the main placenta in a similar way of human extra-villous trophobasts that deeply intrude inside the endometrium and sometimes also found outside the uterine wall. Furthermore, this animal also develops inverted yolk sac placenta defined as fetal membrane partially or fully devoided of trophoblast sheet that allows extra-embryonic endoderma direct exposition to the maternal environment. These characteristics denote a distinct control mechanism of maternal immune response from the established paradigm for human and rodents (rat and mouse) reproduction, being most intriguing the depriving of trophoblast as cells of maternal-fetal interface regulating the maternal immune tolerance. The present work aimed to establish the organization of guinea pig yolk sac based on identification of cell populations composing this membrane and identification if, or, when the trophoblast cells are removed from and subsequent interaction way of yolk sac cell in interface with maternal tissue. It was used pregnant guinea pig sacrificed on established gestational day to collect uterine fragments on early pregnancy stage and processed by conventional paraffin embedding. Due to absence of known specific cell markers for guinea pig, was performed the prospective evaluation using PAS and toluidine blue (TB) cytochemistry and a screening using a panel of biotinylated lectin specific for different sugars and, anti-cytokeratin. The PAS and TB staining did not identify any specific cell population, however, among the lectins used, Erytrina cristagali lectin (ECL) showed high selective labeling to the trophoblast cells originated from the trophectoderm that was kept through the gestational period. This reaction pattern was useful to evaluate chronologically and topologically the fate of this cell and confirmed the constancy of these cells layering the yolk sac placenta in contact with maternal tissue and therefore, endodermal cells were not exposed to maternal environment. Evaluation of embryo development step by step in the serial sections showed the presence of two inner cell mass in opposite sites inside the pre-hatched blastocyst. One of this, was formed with embryoblast that latter will originate the embryonic sheets and the other formed with trophoblast stem cells (ST) will originate the ectoplacental-cone. The wall of blastocele cavity separate these two inner cell mass was initially covered by a single ECL positive mural trophoblast and only later after the amniotic cavity is formed the extraembyonic endodermal cells migrate from the embryonic sheets to cover internally the blastocele cavity to organize the yolk sac placenta. These findings show the peculiarity of guinea pig embryogenesis, quite different from those described for human and rodents and therefore, does not allow direct analogy and seems to contribute in the misunderstanding of classic description of inverted yolk sac placenta and its cellular organization. It means, the trophoblast cell participates in the early organization of yolk sac placenta and remains in chorioamniotic yolk sac fetal membrane constantly limiting the embryo surface in contact with maternal environment. Therefore, the hypothesis of complete or partially inverted yolk sac placenta seems to be a miss understanding of guinea pig embryogenesis.
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BELLEZZA, SIMONA. "A Polyphasic approach to the study of EPS-producing heterocystous cyanobacteria from biofilms in Roman hypogean monuments." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2008. http://hdl.handle.net/2108/603.
Full textAbstract:
Roman hypogea (e.g. the Roman catacombs) are man-made low-light environments of great archaeological and cultural interest. Few species of cyanobacteria are able to colonise the lithic surfaces inside the catacombs, where they live in close vicinity to the artificial lamps associated with green algae, diatoms and bacteria in the life-form of biofilms. Biofilm formation is due to the production of an exopolymeric matrix mostly composed of exopolysaccharides and it is well known that these polymers are involved in the aesthetic and structural alteration of the properties of artistic surfaces (biodeterioration), particularly when rich in negatively charged groups.
Based on this information, the aim of the present work was firstly the identification of the cyanobacterial species involved in biodeterioration process and dominating the biofilms collected in Roman hypogea, and secondly the characterisation of the exopolysaccharides that they secrete to form the mucous matrix of the biofilm.
For the isolation of new cyanobacterial strains, selected sites of the Roman catacombs of St. Callistus and Domitilla were chosen for biofilm collection and recording of physico-chemical parameters.
Taxonomical identification of five heterocystous cyanobacterial strains previously isolated (Scytonema julianum CP6, Scytonema julianum CSC7-21, Scytonema ocellatum CP8-2, Fischerella sp. CSC9d* and Fischerella maior NAV10bis) was done using a “polyphasic approach”, combining cytomorphological observations at light and transmission electron microscopy and molecular phylogeny based on the 16S rRNA gene analysis.
Exopolysaccharides (EPS) from different heterocystous cyanobacterial strains were characterised using different methods: i) cytochemical techniques to evidence the different distribution of EPS; ii) testing different exopolysaccharide extraction protocols; iii) CD (circular dichroism) and RP-HPLC on EPS to characterised their physico-chemical and biochemical properties; iv) quantitative analysis to determine the influence of different light conditions and incubation period on EPS production.
Twenty cyanobacterial taxa were isolated and are maintained in controlled conditions of light, temperatures and humidity and will be added to the “Tor Vergata” culture collection being available for further cytomorphological, ecophysiological and molecular studies.
Cytomorphological and cytochemical studies were useful to determine the diacritical features of the genera. Moreover, the two species Scytonema julianum and S. ocellatum could be distinguished on the ground of cytomorphological features and molecular tools based on sequence similarities of the 16S rRNA genes confirmed this assignment. The same investigations done on the five isolates showed that all the strains but CP6 and CSC7-21 belong to different species. The two phylogenetic trees (maximum parsimony and neighbour joining) highlighted that: i) the two strains CP6 and CSC7-21 clustered with other terrestrial Scytonema species; ii) Fischerella maior NAV10bis and Scytonema ocellatum CP8-2 clustered together and shared a percent sequence similarity over 95%, suggesting that they possibly belong to the same genus, not yet defined; iii) the two strains of Fischerella belong to different species and possibly to different genera, sharing a low percent sequence similarity (90%). Thus, the assignment of these strains to the genus Fischerella needs a revision. This conclusion could not be drawn only on the ground of cytomorphological studies.
The ultrastructural and cytochemical studies showed in the strains CP8-2 and NAV10bis the presence of a bi-stratified sheath, in both species rich in negative charges (sulphated and carboxylic groups). The protocol for EPS extraction using sulphuric acid 0.5 M was quantitatively the most effective, and caused the complete removal of the sheath. CD spectra on exopolysaccharides from the studied strains did not show any conformational transition by varying pH and temperatures, concluding that the polymers follow a “random coil” model, as shown for similar macromolecules. The highest production of EPS under different cultural conditions was obtained from the 8 month old cultures under high irradiances of the strains S. ocellatum CP8 and Fischerella sp. CSC9d*. Moreover, both uronic acids (galacturonic and glucuronic) were produced in each 8 month old culture grown under high irradiance, confirming that these groups in EPS increase with incubation period and metabolic stress. Since the presence of uronic acids is detrimental for the lithic surfaces because of their ability to scavenge cations from the substratum, the most damaging species among those analysed are the Fischerella strains, being the best producer of these negatively charged groups.
In conclusion, this study improves the knowledge on poorly studied cyanobacterial strains from archaeological underground sites by increasing the “Tor Vergata” culture collection with twenty new isolates and using the polyphasic approach to describe five heterocystous cyanobacterial strains. This approach is into line with current trends on the taxonomy of cyanobacteria.
Moreover, useful information for the development of new strategies for the control and prevention of the biodeterioration were obtained. In fact, the quantification of EPS secretion (in particular with regard to the uronic acid) and the characterisation of the climatic conditions that sustain the over-production of these macromolecules can be useful to identify the most damaging cyanobacterial taxa. To this purpose, the new, effective extraction protocol tested will facilitate the complete removal of exopolysaccharides from the little biomass available, being the cyanobacterial biofilms from catacombs usually very thin.
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Fontes, José Eraldo do Nascimento. "Estudo fitoquímico e investigação da atividade citotóxica das folhas de Guatteria pogonopus Mart. (Annonaceae)." Pós-Graduação em Química, 2014. https://ri.ufs.br/handle/riufs/6094.
Full textAbstract:
This work describes the results obtained from the phytochemical study, chemometric analysis and activity cytotoxic in vitro and in vivo of the leaves Guatteria pogonopus Mart., a species of Annonaceae that occurs in Sergipe. The leaves were subjected to two processes. In the first, the leaves were conducted extraction and the study of the chemical composition of the essential oil, considering the seasonality effect; in the second, the isolation of fixed compounds was performed on order to identify alkaloids. Both studies were evaluated towards the antitumor activity in vitro and in vivo. Yields of essential oils ranged from 0.34 % for the month of October/2012 to 0.10 % for the month of September/2012. This variation can be explained by the climate, which the rainfall was higher in September compared to October. This means that the greater the amount of precipitation, reduced yield. The sesquiterpene hydrocarbons were the main constituents of the oils in the samples, with the highest concentration in the month of July/2012 (71.93 %). They were identified as á- and â-pinene, bicyclogermacrene, germacrene B, ã-patchoulene, spathulenol, á-santalene, (E)-caryophyllene, ã-elemene and globulol. In Principal Component Analysis (PCA), both CP1 and CP2 components can explain 90 % of the total variance. It is remarkable that several compounds have focused on the right of the axis of CP1. This phenomenon explains the regularity of the percentage that appears in each month. The ã-patchouleno, spathulenol and bicyclogermacrene compounds protrude to the left of the axis of CP1. Which are the major compounds of the composition of essential oils predominant in all sampling months. In addition to these one can see (E)-caryophyllene and á-santalene, to a lesser prominence this axis. In Hierarchical Cluster Analysis (HCA) formed groups because of similarities. The results of the in vitro antitumor activity of essential oil showed pronounced cytotoxic activity against NCI-H358M, PC-3M and OVCAR-8 lines. In vivo study oil was able to inhibit tumor growth, thus indicating that the essential oil has a significant antitumor potential. Phytochemical study the alkaloidal sheets from the fraction of methanol extract was possible to date the isolation of six alkaloids encoded as GP-1 (nornuciferine), GP-2 (isocorydine), GP-3 (mixture of the nornuciferine and anonaine), GP-4 (lisycamine) and GP-5 (liriodinene). The identification of the alkaloids was performed by 1D/2D 1H and 13C NMR, MS and GC/MS, and comparison with authentic standards and literature data. The cytotoxicity assay performed with single concentration in the extracts and fractions (50 mg/ml) and basic substances (25 mg/mL) revealed promising results with minimal inhibition of 50 % of at least one tumor cell lines. Among the extracts, fractions and evaluated substance, the alkaloidal fraction and compounds GP-1 were the most active against strains B16-F10 and HepG2. Because the activities presented and in order to obtain the IC50 for these two samples front lines K562, HL-60 cells and PBMC were also evaluated. Both the alkaloidal fraction and the compound GP-1 showed good results. The results indicated that G. pogonopus is a biologically active cytotoxic properties with promising source of compounds.Este trabalho descreve os resultados do estudo fitoquimico, analise quimiometrica e investigacao citotoxica in vitro e in vivo das folhas de Guatteria pogonopus Mart. uma especie de Annonaceae de ocorrencia em Sergipe. As folhas foram submetidas a dois processos: no primeiro, foi realizada a extracao e o estudo da composicao quimica do oleo essencial, levando em consideracao o efeito da sazonalidade. Enquanto que no segundo, foi realizado o isolamento de compostos fixos visando a identificacao de alcaloides. Ambos estudos foram avaliados frente a atividade antitumoral in vitro e in vivo. Os rendimentos dos oleos essenciais variaram de 0,34% para o mes de outubro/2012 a 0,10% para o mes de setembro/2012. Essa variacao pode ser explicada pelo clima, o qual o indice pluviometrico foi maior para setembro em relacao a outubro. Isso significa, que quanto maior a quantidade de precipitacao, menor o rendimento. Os sesquiterpenos hidrocarbonetos foram os constituintes majoritarios nas amostras dos oleos, com maior concentracao no mes de julho/2012 (71,93%). Os constituintes majoritarios identificados foram Ñ- e £]-pineno, biciclogermacreno, germacreno B, £^-patchouleno, espatulenol, £-santaleno, (E)-cariofileno, £^-elemeno e globulol. Na Analise de Componentes Principais (ACP), as duas componentes CP1 e CP2 conseguem explicar mais de 90% da variancia total dos dados. E possivel notar que varios compostos se concentraram na direita do eixo da CP1. Esse fenomeno explica a regularidade da porcentagem que aparece em cada mes. Os compostos £^-patchouleno, espatulenol e biciclogermacreno se sobressaem para esquerda do eixo da CP1. Os quais sao os compostos majoritarios da composicao dos oleos essenciais predominante em todos os meses de coleta. Na Analise de Agrupamento Hierarquico (AAH) formaram-se grupos devido a semelhancas. Os resultados da atividade antitumoral in vitro do oleo essencial indicaram pronunciada atividade citotoxica contra as linhagens de NCI-H358M, PC-3M e OVCAR-8. No estudo in vivo o oleo foi capaz de inibir o crescimento tumoral, indicando assim, que o oleo essencial apresenta um potencial antitumoral significativo. Do estudo fitoquimico da fracao alcaloidica do extrato metanolico foi possivel ate o momento o isolamento de seis alcaloides codificados como GP-1 (nornuciferina), GP-2 (isocoridina), GP-3 (nornuciferina e anonaina em mistura), GP-4 (lisicamina), GP-5 (liriodenina). A identificacao dos alcaloides foi realizada por RMN de 1H e 13C 1D/2D, EM e CG/EM, bem como comparacao com padroes autenticos e dados da literatura. O ensaio de atividade citotoxica em concentracao unica realizado com os extratos e fracoes (50 £gg/mL) e substancias puras (25 £gg/mL), revelaram resultados promissores com inibicao minima de 50% de pelo menos uma das linhagens tumorais. Entre os extratos, fracoes e substancia avaliadas, a fracao alcaloidica e o composto GP-1 foram os mais ativos contra as linhagens B16-F10 e HepG2. Devido as atividades apresentadas e com o objetivo de se obter a CI50 essas duas amostras tambem foram avaliadas frente as linhagens de celulas K562, HL-60 e PBMC. Tanto a fracao alcaloidica como o composto GP-1 apresentaram bons resultados. Os quais indicaram que G. pogonopus e uma fonte promissora de compostos biologicamente ativos com propriedades citotoxicas.
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Santisteban, Otegui Maria Soledad. "Etude in situ de la relation structure-fonction de la chromatine par analyse d'images en fluorescence : [thèse en partie soutenue sur un ensemble de travaux]." Grenoble 1, 1993. http://www.theses.fr/1993GRE10060.
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Bussieres, Laurence. "Etude de la na-k-atpase renale par cytochimie quantitative." Paris 6, 1987. http://www.theses.fr/1987PA066289.
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Khadhraoui, Boutheina. "éco-extraction assistée par ultrasons des plantes médicinales : mécanisme(s), intensification et industrialisation ULTRASOUND TECHNOLOGY FOR FOOD PROCESSING, PRESERVATION AND EXTRACTION Histo-cytochemistry and scanning electron microscopy for studying spatial and temporal extraction of metabolites induced by ultrasound. Towards chain detexturation mechanism Microscopic imaging as a tool to target spatial and temporal extraction of bioactive compounds through ultrasound intensificationUltrason. Review of Alternative Solvents for Green Extraction of Food and Natural Green solvents for analytical chemistry." Thesis, Avignon, 2019. http://www.theses.fr/2019AVIG0715.
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Le retour à la naturalité a favorisé le développement des compléments alimentaires à base de ressources végétales qui apparaissent comme un réservoir quasi-infini de nutriments et de substances naturelles bioactives. Ceci fait de l’extraction solide/liquide une étape incontournable au sein des industries intéressées par ce type de molécules. Avec les préoccupations environnementale set sociétales, il est devenu nécessaire d’inventer et développer de nouveaux procédés qui répondent aux six principes de l’éco-extraction. Cette démarche a totalement inspiré cette thèse qui a pour principal objectif le développement d’une technique d’éco-extraction assistée par ultrasons en substitution de la technique conventionnelle. Ce travail a permis de montrer qu’il était possible d’intensifier l’extraction de composés d’intérêt en utilisant les ultrasons avec une meilleure sélectivité et de meilleurs rendements d’extraction. Une attention particulière a été accordée à la compréhension des mécanismes d’action des ultrasons via une étude macroscopique et microscopique approfondie des structures végétales. Cette investigation a prouvé que les ultrasons agissent différemment en fonction des structures végétales et de leurs propriétés morphologiques et chimiques qui leur confèrent un degré de résistance plus ou moins important face à l’action des ultrasons. Partant de ces résultats, l’étude macroscopique et microscopique a été définie comme un outil de décision pour une extraction ciblée. Cette variabilité a été aussi constatée à l’échelle industrielle prouvant davantage l’importance de l’analyse microscopique. Enfin, le procédé d’extraction par ultrasons a été adopté à l’échelle industrielle pour ses performances d’extraction et pour son empreinte environnementale significativement réduite par rapport au procédé CV. Ce travail a également conduit à des travaux complémentaires sur l’étude du potentiel de solubilisation des produits naturels en vue d’une utilisation pour l’extraction de composés végétaux difficiles à solubiliser dans l’eau. Des résultats prometteurs ont été obtenus en termes de pouvoirs de solubilisation et d’extraction notamment à partir de la matière végétale broyée. Les résultats de cette dernière partie soulèvent cependant des questions qui pourraient faire l’objet de futures recherches et de perspectives pour ce travail qui sont principalement liés à l’étude des problèmes liés au changement du solvant et au prétraitement de la matière première et de la faisabilité industrielle de ce nouveau procédéWith recent trends in the increasing interest to environmental, economic and safety considerations,extraction techniques have largely focused on finding solutions with sustainable and green values toimplement in food processing, cosmetic and pharmaceutical industries. In this context, new “green”extraction techniques were developed such as Ultrasound-Assisted Extraction (UAE). The mainobjective of this thesis is industrial implementation of this new process in substitution to theconventional (CV) process. It has been shown in this work that the extraction of compounds ofinterest from rosemary and other plant matrices could be intensified using ultrasound, and thatdifferent performance gain could be achieved according to the plant matrix structural properties.Indeed, macroscopic and microscopic investigation of untreated and treated raw materials provedthat US act through different mechanisms and its resulting impacts can be extremely limited by plantstructural morphological and chemical properties, especially those of the specialized structures.Significant variability in performance gain was also observed at the industrial scale. Overall, USappears as a promising technique with a significant performance gain in terms of extraction yield andselectivity. Moreover, this process presents low environmental footprint compared to the CV one.Finally, it has been shown that natural products, such as honey and fruit juices, can be used toimprove solubilization and extraction of molecules that are poorly soluble in water. Encouragingresults were obtained in terms of solubilization and extraction abilities, especially from ground rawmaterials. However, these results raise questions related to the feasibility of industrialimplementation of this new process
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Rusaouën-Innocent, Maggy. "Association de proteines tannees et de collagene dans l'elaboration de la capsule ovigere par la glande nidamentaire chez scyliorhinus canicula (l. )." Paris 6, 1987. http://www.theses.fr/1987PA066610.
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PERRIN-WALDEMER, CLAUDE GILBERT. "Etude des glandes accessoires du male de drosophila melanogaster (meigen) : cytophysiologie et cytochimie." Clermont-Ferrand 2, 1987. http://www.theses.fr/1987CLF2E359.
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Grellier, Brigitte. "Approche biotechnologique des mycorhizes : culture in vitro et physiologie des associations ectomycorhiziennes." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37605677t.
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Roediger, W. E. W. "A cytochemical study of the c cell in the thyroid glands of young dogs and human neonates." Thesis, 2015. http://hdl.handle.net/10539/19222.
Full textAbstract:
A cytochemical analysis was undertaken of C cells of thyroid
glands obtained from sixteen young oogs and five human s t ill - b o r n
neonates.
Tissues were fixed in selective liquid fixatives (N e lly 's , Carnoy s,
glutaraldehyde-picric-acetic acid, glutaraldehyde-potassium dichromatesodium
sulphate and formol-saline) or fixed in formalin vapour a f t e r
freeze drying. Cryostat sections and some of the above fixatives were
used for enzyme demonstration.
Simple and conjugated proteins in the cytoplasm of canine C cells
were studied by numerous cytochemical reactions. Acetylatiun, methylation,
benzoylation, nitrosation, acid hydrolysis and aldehyde blockade as well
as enzyme hydrolysis were employed to evaluate the aldehyde fuchsin,
colloidal iron, toluidine blue and periodic acid-Schiff staining reactions
in canine C cells.
I have confirmed that the cytoplasm of canine C cells contains an
abundance of acidic protein groups which are due to side-chain carboxyls.
Mild acid hydrolysis, amongst other reactions, may result in peptide
hydrolysis at the aspartyl group, which hydrolysis contributes to the
anionic charge in the C cell cytoplasm. Basic proteins are not readily
stained in the canine C c e l l . Bisulphide groups are numerous and their
oxidation adds to the negative charge of the C cell cytoplasm.
I found that the positive aldehyde fuchsin and colloidal iron
reactions are not attributa ole to mucosubstances such as sulphomucms,
sialomucins or acidic mucopolysaccharides, but seem to be imparted by an acidic protein unconjugated to polysaccharide. A positive aldehyde
fuchsin reaction probably depends on both disulphidc and carboxyl
groups within C c e lls . A positive colloidal iron reaction in canine C
cells requires the presence of carboxyl groups but an increased number of
these groups does not enhance the staining reaction.
The conditions required generally for s ilv e r binding and more
specifically for the Grimelius s ilv e r impregnation in canine C cells
were evaluated by oxidation and various other cytochemical procecures.
I found that the argyrophilia of thyroid C colls depends upon an
exogenous reducing agent and upon pH, optimal impregnation occurring at
a s lig h tly acid pH. Oxidation preceding s ilv e r impregnation by the
Grimelius method, reduces the a f f i n i t y of structures in the cell for
s ilv e r n itr a te . Indirect evidence supports the view that argyrophilia
in the C cells depends upon disulphide groups. I t is suggested that
s ilv e r nitrate and disulphide groups react in C cells to form silv e r
nercaptide which produces the argyrophilia.
The presence of C cel s was demonstrated in human neonates by means
of cytochemical methods known to demonstrate C cells in dogs. C cells
were found predominantly in the posterior region and upper pole of both
lobes where they were found scattered in clusters of six to eight cells
per high power f i e l d Two morphological forms of normal human C cells
were observed - an ovoid cell and one with cytoplasmic processes.
By demonstrating oxidative enzymes and masked metachromasia, three
categories of e p ith e lia l cells have been shown in the neonatal thyroid
gland : A ( f o l l i c u i a r ) , C and AC (intermediate) c e lls . The l a t t e r
may be homologous with the oxyphil cells observed in normal and
pathological adult thyroid glands.
The c lin ic a l applications in which I have useo the results of the
above studies are outlined in the la s t section of the dissertation.
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Nobbs, Sally Felstead. "Extraction, isolation and structural determination of organic compounds from Scaevola spinescens R.Br. / by Sally Felstead Nobbs." Thesis, 2001. http://hdl.handle.net/2440/20305.
Full textAbstract:
Includes bibliographical references (leaves 195-202).xi, 205 leaves : ill. (some col.) ; 30 cm.
Scaevola spinescens is an Australian native plant, found widely in the arid to semi-arid regions of South Australia and through into most other states. Aboriginal people of Hawker in South Australia have traditionally used it as a natural medicine to treat a variety of symptoms. The thesis aims to extract, isolate and determine the structure of organic compounds from Scaevola spinescens.
Thesis (Ph.D.)--Adelaide University, Dept. of Chemistry, 2001
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Nobbs, Sally Felstead. "Extraction, isolation and structural determination of organic compounds from Scaevola spinescens R.Br. / by Sally Felstead Nobbs." 2001. http://hdl.handle.net/2440/20305.
Full textAbstract:
Includes bibliographical references (leaves 195-202).xi, 205 leaves : ill. (some col.) ; 30 cm.
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
Scaevola spinescens is an Australian native plant, found widely in the arid to semi-arid regions of South Australia and through into most other states. Aboriginal people of Hawker in South Australia have traditionally used it as a natural medicine to treat a variety of symptoms. The thesis aims to extract, isolate and determine the structure of organic compounds from Scaevola spinescens.
Thesis (Ph.D.)--Adelaide University, Dept. of Chemistry, 2001
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Samidi. "The physical and chemical properties of ray, non-ray and whole wood tissues in Grevillea robusta." Master's thesis, 1993. http://hdl.handle.net/1885/140198.
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CHEN, YAN-CHANG, and 陳衍昌. "Isolation﹑cultivation﹑ultrastructure and cytochemistry of protoplasts from grateloupia sparsa (halymeniaceae, rhodophyta)." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/60574582449759838393.
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Soole, Kathleen Lydia. "Characterisation of the NADH dehydrogenases associated with isolated plant mitochondria." 1988. http://web4.library.adelaide.edu.au/theses/09PH/09phs711.pdf.
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Lin, Qiao. "Myosin-like proteins in plants." Phd thesis, 1993. http://hdl.handle.net/1885/142323.
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ZHOU, YI-PENG, and 周逸鵬. "Ultrastructure, cytochemistry and phosphatase activities of small granule-containing cells in rat superior cervical ganglia." Thesis, 1987. http://ndltd.ncl.edu.tw/handle/46368310632651420535.
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Korves, Tonia M. "Fitness consequences and the evolution of R gene resistance to pathogen infection /." 2002. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3070185.
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Simpson, Bronwyn Jayne. "Mutagenic and purification studies of the carboxyl tail of ClC-1, the skeletal muscle chloride channel." 2002. http://arrow.unisa.edu.au:8081/1959.8/24999.
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ClC-1 is the major skeletal muscle chloride channel and is essential for re-establishing the resting membrane potential of muscle cells after an action potential has occurred. Many mutations throughout the CLCN1 gene, which codes for the CIC-1 protein, have been demonstrated via characterisation in heterologous expression systems, to be causative mutations for either Dominant Myotonia Congenita or Recessive Generalised Myotonia. Recently, increasing numbers of myotonic mutations have been found in the carboxyl tail of CIC-1, which demonstrates its importance as a domain that is essential for the normal function of CIC-1 channels. Previous studies in our laboratory defined a region of 18 amino acids in the immediate post D13 segment of rat CIC-1, essential for the expression of functional channels.thesis (PhDBiomedicalScience)--University of South Australia, 2002.
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Soole, Kathleen Lydia. "Characterisation of the NADH dehydrogenases associated with isolated plant mitochondria / Kathleen Lydia Soole." Thesis, 1989. http://hdl.handle.net/2440/18863.
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