Articles de revues : « Concentration de la norme L3 »

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Sisin, Noor Nabilah Talik, Merfat Algethami, Awatef S. Assran et Wan Nordiana Rahman. « Analysis of Novel Schiff Base-Fe Complexes Against Breast Cancer Cells’ Viability ». Key Engineering Materials 965 (28 novembre 2023) : 59–68. http://dx.doi.org/10.4028/p-cnfqt2.

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Two potential novels Schiff base iron (Fe) complexes Fe-L2 and Fe-L3 (where L2= N, N'-bis (o-hydroxyacetophenone) ethylenediamine and L3= N, N'-bis (o-hydroxybenzaldehyde) phenylenediamine) were synthesized from interaction a hot methanolic solution of each ligand L2 or L3 (0.01mole) with the appropriate amount of Fe (NO3)3.9H2O metal salt (0.01mole). This study investigated the cytotoxicity induced by both complexes (0.1 to 100 µg/ml) in MCF-7 and MDA-MB 231 cell lines. After 24 hours of treatment, the cell viabilities of both MCF-7 and MDA-MB-231 cells were linearly proportional to the Fe-L2 concentrations. A higher concentration of Fe-L2 would cause higher cell killings. On the other hand, most of the Fe-L3 concentrations caused total cell deaths for both cell lines, except for the lowest concentration (0.1 µg/ml). Fe-L2 and Fe-L3 also caused lower cell viability of MDA-MB-231 cells compared to MCF-7 cells. Overall, the obtained Fe-L3 is more toxic than Fe-L2 in breast cancer cells. It is suggested that the Fe-L3 is an excellent agent against breast cancer cells; meanwhile, the Fe-L2 is biocompatible and a good support in medical applications, especially as a radiosensitizer in radiotherapy.

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Mitsui, Y., M. Miura, D. A. Bome et Y. Aoki. « In vitro chemotactic responses of Brugia pahangi infective larvae to sodium ions ». Journal of Helminthology 86, n^o 4 (27 octobre 2011) : 406–9. http://dx.doi.org/10.1017/s0022149x11000605.

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AbstractIn vitro chemotactic responses of infective third-stage larvae (L3) of Brugia pahangi to NaCl, Na2HPO4, KCl, K2HPO4, MgCl2 and CaCl2 were assessed. Compared to deionized water as a control, 200 mm NaCl and 100 mm Na2HPO4 significantly attracted L3 (P < 0.01 and P < 0.01), whereas L3 were likely to avoid 200 mm KCl and 100 mm K2HPO4 (P < 0.05 and P < 0.05). L3 showed no significant tendency to avoid or to be attracted to 200 mm CaCl2 and 200 mm MgCl2. Furthermore, NaCl exhibited a significant chemoattractant activity for L3 at a low concentration of 100 mm.

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Shahiduzzaman, M., MK Islam, M. Rahman et MMH Mondal. « IN VITRO EFFECTS OF SOME HOUSEHOLD CHEMICALS ON INFECTIVE LARVAE OF HAEMONCHUS CONTORTUS OF GOAT ». Bangladesh Journal of Veterinary Medicine 3, n^o 1 (22 juillet 2012) : 55–58. http://dx.doi.org/10.3329/bjvm.v3i1.11355.

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In vitro effects of some household chemicals on infective larvae (L3) of Haemonchus contortus of goat were screened during the period from January 2002 to April 2003. Solutions of 0.5, 1, 5, 10 and 20 mg / ml were screened for in vitro effects on infective larvae (L3) of Haemonchus contortus. The percent non-motile L3 was increased when immersed in increasing solutions of the household chemicals (p < 0.01) except sodium chloride. Of 10 household chemicals, potassium permanganate showed 100% in vitro larvicidal effect at 1 mg / ml concentration. Boric acid showed the second highest larvicidal effect (78.95%) followed by alum (71.86%), bleaching powder (71.43%) and borax (68.97%) at their highest concentration of 20 mg / ml.

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Smet, P. W., T. F. Pauwels et P. J. Dierickx. « The effect of hexaaza-and hexathia–macrocyclic ligands on transition metal cytotoxicity in human hepatoma-derived cultured cells ». Human & ; Experimental Toxicology 21, n^o 8 (août 2002) : 421–27. http://dx.doi.org/10.1191/0960327102ht277oa.

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The effect of macrocyclic ligands on cytotoxic concentrations of the transition metal ions of copper, zinc, and cadmium was investigated. For this purpose, a hexaaza-[3,6,9,17,20,23-hexaazatricyclo[23.3.1.111,15] triaconta–1(29),11(30),12,14,25,27–hexaene (L2)] and hexathia-chelating ligand [1,4,7,10,13,16-hexathiacyclooctadecane (L3)] were used in the human hepatoma-derived HepG2 cell line. The cytotoxicity was measured by the neutral red uptake inhibition assay. First, the NI50 of the ligands, i.e., the concentration of the ligand inducing a 50% inhibition in neutral red uptake compared to control cells, was determined. In several metal/ligand combination experiments, the effects for L2 were difficult to interpret, whereas for L3 in combination with copper ions, a severe increase–and for zinc ions, a significant decrease of cell toxicity–relative to the metal control was observed. To further examine the different effects observed with L3 in combination with, respectively, Cu2+ and Zn2+, the glutathione (GSH) content was measured. The relative GSH content decreased as the concentration of L3 increased. It was proposed that the increased toxicity of the combination Cu2+ /L3 could be caused by the depletion of GSH and a subsequent inability to scavenge the produced reactive oxygen species (ROS). This hypothesis was supported by experiments during which vitamin E or C was added to the Cu2+ / L3 system.

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De Silva, Warusavithana Gunawardena Manori, Bianca Yuko McCarthy, Jeremy Han, Chen Yang, Andrew J. A. Holland, Harvey Stern, Katie Marie Dixon et al. « The Over-Irradiation Metabolite Derivative, 24-Hydroxylumister-ol3, Reduces UV-Induced Damage in Skin ». Metabolites 13, n^o 7 (21 juin 2023) : 775. http://dx.doi.org/10.3390/metabo13070775.

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The hormonal form of vitamin D3, 1,25(OH)2D3, reduces UV-induced DNA damage. UV exposure initiates pre-vitamin D3 production in the skin, and continued UV exposure photoisomerizes pre-vitamin D3 to produce “over-irradiation products” such as lumisterol3 (L3). Cytochrome P450 side-chain cleavage enzyme (CYP11A1) in skin catalyzes the conversion of L3 to produce three main derivatives: 24-hydroxy-L3 [24(OH)L3], 22-hydroxy-L3 [22(OH)L3], and 20,22-dihydroxy-L3 [20,22(OH)L3]. The current study investigated the photoprotective properties of the major over-irradiation metabolite, 24(OH)L3, in human primary keratinocytes and human skin explants. The results indicated that treatment immediately after UV with either 24(OH)L3 or 1,25(OH)2D3 reduced UV-induced cyclobutane pyrimidine dimers and oxidative DNA damage, with similar concentration response curves in keratinocytes, although in skin explants, 1,25(OH)2D3 was more potent. The reductions in DNA damage by both compounds were, at least in part, the result of increased DNA repair through increased energy availability via increased glycolysis, as well as increased DNA damage recognition proteins in the nucleotide excision repair pathway. Reductions in UV-induced DNA photolesions by either compound occurred in the presence of lower reactive oxygen species. The results indicated that under in vitro and ex vivo conditions, 24(OH)L3 provided photoprotection against UV damage similar to that of 1,25(OH)2D3.

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Mitsui, Y., K. E. Ureña-Tatis et Y. Aoki. « Chemoattractant activity of tris-(hydroxymethyl)aminomethane for Brugia pahangi infective third-stage larvae ». Journal of Helminthology 92, n^o 3 (24 juillet 2017) : 317–21. http://dx.doi.org/10.1017/s0022149x17000645.

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AbstractUrocanic acid (UCA) is known as a major chemoattractant for Strongyloides stercoralis infective third-stage larvae (L3). Since Brugia pahangi is a skin-penetrating parasitic nematode similar to S. stercoralis, UCA was expected to be a chemoattractant for B. pahangi L3. Thus, the chemoattractant activity of UCA for B. pahangi L3 was assessed. The chemotactic responses of B. pahangi L3 to UCA or acetic acid (CH3COOH) dissolved in amine solutions were assessed using an agar-plate assay. A test solution of 200 mm UCA dissolved in aqueous 270 mm tris(hydroxymethyl)aminomethane (Tris) significantly attracted B. pahangi L3 compared with deionized water (DW), while neither a solution of 200 mm UCA dissolved in aqueous 230 mm ammonia (NH3) nor 290 mm triethylamine (TEA) significantly attracted L3. Similarly, a test solution of 200 mm CH3COOH dissolved with 200 mm Tris significantly attracted L3, but neither a test solution of 200 mm CH3COOH plus 200 mm NH3 nor 200 mm TEA attracted L3. Furthermore, L3 were significantly attracted to 200 mm Tris alone, compared with DW, but avoided 200 mm NH3 and 200 mm TEA. Moreover, the chemoattractant activity of Tris for L3 was observed even at a low concentration of 25 mm, and it was observed in a mild alkaline condition but not in an acidic condition. The present study reveals that Tris is a potential chemoattractant for B. pahangi L3 while UCA is not. This finding will contribute to an understanding of the mechanisms of skin-penetrating infection of filarial L3.

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Meng, Haining, Xiaojun Lu, Asma Shaheen, Shahid Hussain et Guiwu Liu. « Effects of Temperature, pH, Culture Time, Oscillation Frequency on Self-Healing Microbes and Growth Predictive Model ». Journal of Nanoelectronics and Optoelectronics 16, n^o 10 (1 octobre 2021) : 1638–44. http://dx.doi.org/10.1166/jno.2021.3119.

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To save costs in preparation of Bacillus mucilaginous L3, we studied the effects of culture temperature, pH, culture time, oscillation frequency, and medium concentration on the biomass OD600 of B. mucilaginous L3 using orthogonal tests and back-propagation neural networks. The influence factors on OD600 ranked as importance as temperature > pH > culture time > medium concentration > oscillation frequency. The training precision of the growth predictive model based on back-propagation neural networks was up to 99.308%. The optimal prediction ranges of different factors were temperature: 28–30 °C, pH: 7.1–7.4, medium concentration: 2–4 and 7–8 g/L, culture time: 46–49 h, and oscillation frequency: 175–190 and 120–130 r/min.

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Acevedo-Ramírez, Perla María del Carmen, Claudia Hallal-Calleros, Iván Flores-Pérez, Fernando Alba-Hurtado, María Berenit Mendoza-Garfias et Rubén Barajas. « Nematicidal Effect and Histological Modifications Induced by Hydrolysable Tannin Extract on the Third-Stage Infective Larvae of Haemonchus contortus ». Biology 9, n^o 12 (4 décembre 2020) : 442. http://dx.doi.org/10.3390/biology9120442.

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Haemonchus contortus is the most frequent and most important nematode parasite in the ruminants production of tropical and subtropical regions. There are strains resistant to all families of available anthelmintics. Consequently, the conduction of research to find other resources that allow effective control of this parasitic disease, preferably focusing on green production, is necessary. The aim of this study was to evaluate the effect of hydrolysable tannin extract (HTE) on larvae 3 (L3) of H. contortus in vitro. L3 were exposed to different HTE concentrations and times. In addition, both light and scanning electron microscopy were used to explore physical damage on L3 subjected to HTE activity. After 72 h of incubation, the mean lethal concentration of HTE was 2 mg/mL; this concentration has been previously referred to as safe for consumption in cattle. Scanning electron microscopy revealed H. contortus L3 destruction, damage was evident by separation of the sheath mainly in the cervical and caudal regions of the larva and by rupture of the cuticle with larval evisceration. Our results suggest that hydrolysable tannin extract from chestnut could be considered as a green alternative for parasitic control in ruminants.

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Łopieńska-Biernat, E., K. Żółtowska et J. Rokicki. « The content of carbohydrates in larval stages of Anisakis simplex (Nematoda, Anisakidae) ». Helminthologia 43, n^o 3 (1 juin 2006) : 125–29. http://dx.doi.org/10.2478/s11687-006-0024-y.

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AbstractThe content of carbohydrates in L3 and L4 larvae of Anisakis simplex (defined by Rokicki J.) was studied. Glycogen and trehalose were their major reserve sugars. The concentration of saccharides in L4 larvae was 2–3-times higher than in L3 larvae. The content of glycogen was 3.68 ± 1.24 mg/g tissue in L3 larvae and 11.68 ± 1.21 mg/g tissue in L4 larvae. Trehalose represented 16.17 % of soluble sugars in L3 larvae and 43.04 % in L4 larvae. The contents of maltose, higher polymers of glucose (1.5-times) and myoinositol (1.2-times) in L4 were higher than in L3 larvae. After starving the L3 larvae of the parasite for 48 h at 4°C, the contents of trehalose increased 5-fold and that of glycogen by 20 %, while at 37°C the contents of glycogen was ca. 30 % higher and that of trehalose 40 % less than in larvae freshly isolated from the host (p < 0.01). The data obtained during starving the L3 larvae of A. simplex may be a consequence the role of trehalose as protective compound at stress condition. We suggest that probably in higher temperatures it acts as first a source of energy, and it also might serve to restore the levels of glycogen.

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Khien, V. V., H. V. Mao, T. T. Chinh, P. T. Ha, M. H. Bang, B. V. Lac, T. V. Hop et al. « Clinical Evaluation of Lentil Lectin-Reactive Alpha-Fetoprotein-L3 in Histology-Proven Hepatocellular Carcinoma ». International Journal of Biological Markers 16, n^o 2 (janvier 2001) : 105–11. http://dx.doi.org/10.1177/172460080101600204.

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Introduction Serum alpha-fetoprotein (AFP) is a useful marker of hepatocellular carcinoma (HCC), although the serum AFP concentration is also increased in patients with chronic liver diseases (CLD). The analysis of AFP glycoforms has been known to be of diagnostic value. We applied the lectin-affinity electrophoresis and antibody-affinity blotting techniques to HCC patients in Vietnam in order to better understand the role of lentil lectin-affinity AFP-L3 in the diagnosis and differential diagnosis of HCC, and its relationship with the biological characteristics of HCC. Methods Lens culinaris agglutinin-reactive AFP (AFP-L3) was measured in 65 patients with histologically proven HCC and 25 patients with CLD. All patients had serum AFP levels above 54 ng/mL. AFP-L3 levels were determined by lectin affinity electrophoresis coupled with antibody-affinity blotting. The diagnosis of HCC was confirmed histologically by ultrasound-guided biopsy. Results The mean value of AFP-L3 in the HCC patients was 49.6 ± 21.6%, which was significantly higher (p<0.001) than that in the 25 CLD patients (10.7 ± 4.3%). When the cutoff level for AFP-L3 was set at 15% (mean ± SD), the sensitivity was 96.9%, the specificity 92.0% and the accuracy 95.5% in the 65 HCC patients. There was no clear correlation between serum AFP level and AFP-L3 percentage (r=0.16). There was no correlation between AFP-L3 and the maximum diameter of HCC nodules (r=0.05). However, the mean AFP-L3 value was higher in moderately or poorly differentiated HCC than in well differentiated tumors (p<0.001). Conclusions AFP-L3 is potentially a clinically useful marker for the differentiation of increased AFP levels in hepatocellular carcinoma and chronic liver diseases. The AFP-L3 percentage is closely related to HCC differentiation. We consider the analysis of AFP-L3 a useful adjunct in the diagnosis of HCC.

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Jayabhavan, Sreejith Sudhakaran, Baldur Kristinsson, Dipankar Ghosh, Charlène Breton et Krishna K. Damodaran. « Stimuli-Responsive Properties of Supramolecular Gels Based on Pyridyl-N-oxide Amides ». Gels 9, n^o 2 (20 janvier 2023) : 89. http://dx.doi.org/10.3390/gels9020089.

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The nature of functional groups and their relative position and orientation play an important role in tuning the gelation properties of stimuli-responsive supramolecular gels. In this work, we synthesized and characterized mono-/bis-pyridyl-N-oxide compounds of N-(4-pyridyl)nicotinamide (L1–L3). The gelation properties of these N-oxide compounds were compared with the reported isomeric counterpart mono-/bis-pyridyl-N-oxide compounds of N-(4-pyridyl)isonicotinamide. Hydrogels obtained with L1 and L3 were thermally and mechanically more stable than the corresponding isomeric counterparts. The surface morphology of the xerogels of di-N-oxides (L3 and diNO) obtained from the water was studied using scanning electron microscopy (SEM), which revealed that the relative position of N-oxide moieties did not have a prominent effect on the gel morphology. The solid-state structural analysis was performed using single-crystal X-ray diffraction to understand the key mechanism in gel formation. The versatile nature of N-oxide moieties makes these gels highly responsive toward an external stimulus, and the stimuli-responsive behavior of the gels in water and aqueous mixtures was studied in the presence of various salts. We studied the effect of various salts on the gelation behavior of the hydrogels, and the results indicated that the salts could induce gelation in L1 and L3 below the minimum gelator concentration of the gelators. The mechanical properties were evaluated by rheological experiments, indicating that the modified compounds displayed enhanced gel strength in most cases. Interestingly, cadmium chloride formed supergelator at a very low concentration (0.7 wt% of L3), and robust hydrogels were obtained at higher concentrations of L3. These results show that the relative position of N-oxide moieties is crucial for the effective interaction of the gelator with salts/ions resulting in LMWGs with tunable properties.

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Sakura, Shinichi, Mariko Sumi, Noriko Morimoto, Yuji Yamamori et Yoji Saito. « Spinal Anesthesia With Tetracaine in 0.75% Glucose : Influence of the Vertebral Interspace Used for Injection ». Regional Anesthesia & ; Pain Medicine 23, n^o 2 (mars 1998) : 170–75. http://dx.doi.org/10.1136/rapm-00115550-199823020-00010.

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Background and ObjectivesThe anesthetic behavior and hemodynamic consequences of spinal anesthesia with marginally hyperbaric tetracaine containing a low concentration of glucose injected at two different interspaces were examined and compared with those of conventionally hyperbaric solution.MethodsOne-hundred twenty ASA Physical Status I or II patients scheduled for elective surgery to the lower limb were sequentially assigned to one of three equal groups to receive spinal anesthesia: Group 1 received 0.5% tetracaine in 0.75% glucose with 0.125% phenylephrine at the L2-L3 interspace; group 2 0.5% tetracaine in 0.75% glucose with 0.125% phenylephrine at the L3-L4 interspace; group 3 0.5% tetracaine in 7.5% glucose with 0.125% phenylephrine at the L3-L4 interspace. Neural block was assessed in a double-blinded manner by cold, pinprick, and touch sensation, and a modified Bromage scale after the injection of the study drug.ResultsInjection at the L2-L3 interspace produced significantly higher spread of analgesia [median T7 (10th, 90th percentiles T10, T4)] than injection at L3-L4 interspace [T10 (L1, T5)] when using the solution in 0.75% glucose. There were no significant differences in peak dermatomal levels between groups 1 and 3, but the number of patients who required ephedrine for the treatment of hypotension was larger in group 3.ConclusionsA marginally hyperbaric tetracaine solution injected at the L2-L3 interspace with the patient in the lateral position produced greater extent of cephalad spread than that at the L3-L4 interspace. When compared to a conventionally hyperbaric tetracaine solution injected at the L3-L4 interspace, the marginally hyperbaric solution injected at the L2-L3 interspace caused less hemodynamic variability despite similar levels of maximum sensory block.

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Elegbede, Joseph Adetunji, et Agbaje Lateef. « Optimization of the production of xylanases in corncob-based media by Aspergillus niger and Trichoderma longibrachiatum using Taguchi approach ». Acta Biologica Szegediensis 63, n^o 1 (25 juillet 2019) : 51–58. http://dx.doi.org/10.14232/abs.2019.1.51-58.

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Xylanases are important in producing several commercially valued bioproducts. In this study, xylanases were produced by Aspergillus niger L3 and Trichoderma longibrachiatum L2 using corncob, an agricultural waste, as sole carbon source. The impact of important fermentation parameters at individual and interactive levels were studied using Taguchi L9 orthogonal array. Substantial variation in enzyme synthesis was observed among designated factor levels. The optimal conditions to produce xylanases were 20% inoculum size, 24 h fermentation time, substrate concentration of 15 g/l at pH 5.5 for A. niger L3; and inoculum size 12.5%, 72 h fermentation time, substrate concentration of 15 g/l at pH 5.5 for T. longibrachiatum L2. Validation of outcomes of the optimal combination of parameters resulted in a significant improvement of approximately 208.09 and 192.59% in the yield of xylanase by A. niger L3 (28.69 to 88.39 U/ml) and T. longibrachiatum L2 (22.13 to 64.75 U/ml), respectively. The study therefore established the optimal valorization of corncob to produce xylanase by the fungal isolates.

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Cowley, F. C., D. G. Barber, A. R. Anstis, A. Houlihan et D. P. Poppi. « Immediate, cumulative and residual effects of short- and long-term low plane of nutrition on milk protein and casein composition ». Animal Production Science 54, n^o 9 (2014) : 1374. http://dx.doi.org/10.1071/an14299.

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Immediate and residual effects of two lengths of low plane of nutrition (PON) on the synthesis of milk protein and protein fractions were studied at the Mutdapilly Research Station, in south-east Queensland. Thirty-six multiparous Holstein-Friesian cows, between 46 and 102 days in milk (DIM) initially, were used in a completely randomised design experiment with three treatments. All cows were fed on a basal diet of ryegrass pasture (7.0 kg DM/cow.day), barley-sorghum concentrate mix (2.7 kg DM/cow.day) and a canola meal-mineral mix (1.3 kg DM/cow.day). To increase PON, 5.0 kg DM/cow.day supplemental maize and forage sorghum silage was added to the basal diet. The three treatments were (C) high PON (basal diet + supplemental silage); (L9) low PON (basal diet only) for a period of 9 weeks; and (L3) low PON (basal diet only) for a period of 3 weeks. The experiment comprised three periods (1) covariate – high PON, all groups (5 weeks), (2) period of low PON for either 3 weeks (L3) or 9 weeks (L9), and (3) period of high PON (all groups) to assess ability of cows to recover any production lost as a result of treatments (5 weeks). The low PON treatment periods for L3 and L9 were end-aligned so that all treatment groups began Period 3 together. Although there was a significant effect of L9 on yields of milk, protein, fat and lactose, and concentrations of true protein, whey protein and urea, these were not significantly different from L3. There were no residual effects of L3 or L9 on protein concentration or nitrogen distribution after 5 weeks of realimentation. There was no significant effect of low PON for 3 or 9 weeks on casein concentration or composition.

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Corici, Claudia, Zsófia Kohajda, Attila Kristóf, András Horváth, László Virág, Tamás Szél, Norbert Nagy et al. « L-364,373 (R-L3) enantiomers have opposite modulating effects on IKs in mammalian ventricular myocytes ». Canadian Journal of Physiology and Pharmacology 91, n^o 8 (août 2013) : 586–92. http://dx.doi.org/10.1139/cjpp-2012-0407.

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Activators of the slow delayed rectifier K+ current (IKs) have been suggested as promising tools for suppressing ventricular arrhythmias due to prolongation of repolarization. Recently, L-364,373 (R-L3) was nominated to activate IKs in myocytes from several species; however, in some studies, it failed to activate IKs. One later study suggested opposite modulating effects from the R-L3 enantiomers as a possible explanation for this discrepancy. Therefore, we analyzed the effect of the RL-3 enantiomers on IKs in ventricular mammalian myocytes, by applying standard microelectrode and whole-cell patch-clamp techniques at 37 °C. We synthesized 2 substances, ZS_1270B (right) and ZS_1271B (left), the 2 enantiomers of R-L3. In rabbit myocytes, ZS_1270B enhanced the IKs tail current by approximately 30%, whereas ZS_1271B reduced IKs tails by 45%. In guinea pig right ventricular preparations, ZS_1270B shortened APD90 (action potential duration measured at 90% repolarization) by 12%, whereas ZS_1271B lengthened it by approximately 15%. We concluded that R-L3 enantiomers in the same concentration range indeed have opposite modulating effects on IKs, which may explain why the racemic drug R-L3 previously failed to activate IKs. ZS_1270B is a potent IKs activator, therefore, this substance is appropriate to test whether IKs activators are ideal tools to suppress ventricular arrhythmias originating from prolongation of action potentials.

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Burggraaf, V. T., A. R. Brooky et C. J. Boom. « Response of beef calves to different levels of postweaning ingestion of gastrointestinal parasite larvae ». Australian Journal of Experimental Agriculture 47, n^o 11 (2007) : 1297. http://dx.doi.org/10.1071/ea06275.

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The postweaning response of beef calves to different levels of gastrointestinal parasite larvae (L3) ingestion was investigated. Newly weaned calves (n = 77, 6 months old) were trickle-dosed with 0, 1000, 2000, 4000, 7000 or 10 000 L3 (75% Cooperia oncophora, 10% Ostertagia ostertagi, 15% Trichostrongylus axei) per day for 10 weeks or drenched with anthelmintic at 3-weekly intervals. Liveweight, faecal egg count and blood serum pepsinogen were monitored regularly. Three calves per treatment were slaughtered following infection to determine adult worm burdens. For the following 11 weeks, liveweight, faecal egg count and serum pepsinogen were monitored for the remaining calves. During the dosing period, calves that were drenched had similar liveweight gain to those receiving up to 2000 parasites per day but grew 0.13–0.20 kg per day more than calves receiving between 4000 and 10 000 L3 per day. Faecal egg counts did not reflect liveweight gains or dose rate for calves receiving more than 2000 L3 per day and pepsinogen concentration did not reflect liveweight performance. Abomasal worm burdens at the end of dosing were highest in treatments receiving 4000 or more L3 per day but intestinal (Cooperia species) burdens were highest in those receiving low infection rates. Liveweight gain during the carryover period for the 4000 L3 treatment was significantly lower than in other treatments. Calves receiving anthelmintic showed a 14–40 kg liveweight advantage by the end of the experiment. This study indicates that to avoid production losses from parasites in beef calves in the absence of anthelmintic the ingestion of parasite larvae should be below 4000 per day.

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Manley, K. M., et J. A. Embil. « In vitro effect of ivermectin on Pseudoterranova decipiens survival ». Journal of Helminthology 63, n^o 1 (mars 1989) : 72–74. http://dx.doi.org/10.1017/s0022149x00008750.

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ABSTRACTThird larval stages (L3) removed from fish fillets, fourth larval stages (L4) raised in in vitro culture, and adults of Pseudoterranova decipiens, collected from grey seal (Halichoerus grypus) stomachs, were exposed to the broad spectrum anthelmintic, ivermectin. L3 and L4 parasites were exposed, in vitro, to 500, 100, 50, 20, 5 and 1 μg/ml concentrations of the drug, in culture media. Adult P. decipiens were exposed in vitro to a concentration of 500 μg/ml ivermectin, only. Controls consisted of parasites placed in culture media alone or culture media plus drug vehicle. These three developmental stages of P. decipiens were all found to be susceptible to the effects of ivermectin.

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Lecová, L., L. Stuchlíková, J. Lamka, M. Špulák, M. Várady et L. Skálová. « Efficacy of monepantel against lower developmental stages of a multi-resistant and susceptible Haemonchus contortus isolates : an in vitro study ». Helminthologia 50, n^o 2 (1 juin 2013) : 91–95. http://dx.doi.org/10.2478/s11687-013-0114-6.

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AbstractMonepantel (MOP) belongs to a new class of anthelmintic compounds, the amino-acetonitrile derivates, which have a different mode of action as the currently used anthelmintics. Many present studies confirmed the high efficacy of MOP against fourth larval and adult stages of Haemonchus contortus. The objective of this study was to determine in vitro efficacy of MOP against lower development stages (eggs, L1–L3 larvae) and to compare it between resistant and susceptible isolates of H. contortus. For this purpose, two in vitro tests - egg hatch test and micro-agar larval development test were used. Results were quantified as 50 % lethal concentration (LC50), 99 % lethal concentration (LC99) and resistance factor (RF). This study revealed the high efficacy against lower larval stages (L1–L3) of both resistant and susceptible strains of this parasite. Larval susceptibility was not dependent of the sensitivity status of the nematode isolate. On the other hand, ovicidal effect of MOP was very low.

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Diop, Tidiane, Adrienne Ndiolene, Alassane Traore, Maguette Ndiaye, Mamadou Sidibe et Cheikh Abdoul Khadir Diop. « Évaluation de la qualité des sels alimentaires consommés au Sénégal ». International Journal of Biological and Chemical Sciences 18, n^o 2 (26 juillet 2024) : 670–77. http://dx.doi.org/10.4314/ijbcs.v18i2.27.

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Le sel de cuisine de qualité alimentaire est iodé pour des motifs de santé publique, pour prévenir les troubles dus à une déficience en iode (TDI). Les quantités maximales et minimales sont normés. Le sel, produit naturel, contient des métaux lourds, des sulfates… en proportion variable. Certains éléments traces métalliques peuvent devenir toxiques lorsque la concentration dépasse un certain seuil. L’objectif de cette étude est d’évaluer la qualité des sels de cuisine au Sénégal. Cette qualité sera évaluée par rapport à la norme Sénégalaise NS03-037 (1994). De septembre à octobre 2022, cent douze (112) échantillons de sels ont été collectés à Dakar, Fatick, Thiès et Kaolack, Tambacounda, Saint-Louis et Ziguinchor. Les teneurs d’iode ont été déterminés par la méthode NS03-038 (1994). Les métaux lourds ont été déterminé par ICP-OES. L’analyse qualitative des sulfates, carbonates et autres éléments chimiques a été effectuée par spectroscopies de fluorescence-x et infrarouge. Le dosage des sulfates a été effectué par spectrophotomètre Hach DR3900 par la méthode turbidimétrique après réaction avec le baryum du réactif SulfaVer 4. Les résultats révèlent que 25% des sels ont des teneurs d’iode comprise entre 30-50 ppm c’est-à-dire adéquatement iodés. Par ailleurs nos résultats ont montré que 50% des échantillons étaient sous-iodés et 25% sur-iodés. Les teneurs en métaux lourds (As, Cd, Hg, Pb et Cu) sont globalement acceptables par rapport à la norme sénégalaise en concordance avec la norme codex. La quantification des sulfates montre de fortes teneurs. L’étude montre que l’état d’iodation des sels n’est pas satisfaisant et ils contiennent d’autres éléments chimiques comme les sulfates. Ceci montre que des actions urgentes doivent être menées pour améliorer la qualité du sel iodé au Sénégal.

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Morávková, Paula, Darina Kohoutová, Jaroslava Vávrová et Jan Bureš. « S100A4 Protein in Inflammatory Bowel Disease : Results of a Single Centre Prospective Study ». Acta Medica (Hradec Kralove, Czech Republic) 60, n^o 3 (2017) : 108–13. http://dx.doi.org/10.14712/18059694.2018.2.

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Introduction: The aim of our study was to assess association of serum S100A4 protein with ulcerative colitis (UC) and Crohn’s disease (CD). Methods: Study included 118 subjects: 93 patients with CD, 16 with UC and 9 controls. In CD group, 20/93 patients had B1 phenotype, 19/93 B2, 20/93 B3 and 34/93 B2 + B3. L1 involvement was present in 15/93, L2 in 14/93 and L3 in 64/93 patients. Serum S100A4 concentration was investigated in peripheral venous blood samples by means of ELISA. Results: Serum S100A4 was significantly higher in UC (158.6 ± 56.2 ng/mL), p = 0.019 and in CD (154.4 ± 52.1 ng/mL), p = 0.007 compared to controls (104.8 ± 40.5 ng/mL). No difference in S100A4 was revealed between UC and CD, p > 0.05. Serum S100A4 in each CD subgroup (according to behaviour) was significantly higher compared to controls, p < 0.05. Serum S100A4 was significantly higher in L2 (144.6 ± 44.2 ng/mL), p = 0.041 and in L3 (163.0 ± 52.8 ng/mL), p = 0.002 compared to controls and in L3 compared to L1 (126.9 ± 47.6 ng/mL), p = 0.017. Conclusion: Association of serum S100A4 protein with UC and CD was confirmed. In CD, disease behaviour did not influence serum concentration of S100A4 protein. In CD, higher levels of serum S100A4 were observed in patients with ileo-colonic and colonic involvement compared to those with isolated small bowel involvement.

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Barone, Carly D., Anne M. Zajac, Sarah M. Ferguson, Rebecca N. Brown, Jess D. Reed, Christian G. Krueger et Katherine H. Petersson. « In vitro screening of 51 birdsfoot trefoil (Lotus corniculatus L. ; Fabaceae) strains for anti-parasitic effects against Haemonchus contortus ». Parasitology 146, n^o 6 (14 janvier 2019) : 828–36. http://dx.doi.org/10.1017/s0031182018002214.

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AbstractSecondary plant compounds have shown bioactivity against multi-drug resistant Haemonchus contortus in small ruminants. This study screened 51 strains of birdsfoot trefoil (BFT, Lotus corniculatus) crude aqueous extracts (BFT-AqE) for anti-parasitic activity in vitro against egg hatching, and of those 51 strains, 13 were selected for further testing of motility of first (L1) and third stage (L3) larvae, and exsheathment of L3. Proanthocyanidin content ranged between 1.4 and 63.8 mg PAC g−1 powder across the 51 BFT strains. When tested against egg hatching, 21 of the 51 aqueous extracts had an EC50 of 1–2 mg powder mL−1, 70% of the strains were >90% efficacious at 6 mg powder mL−1 and 11 of the strains were 100% efficacious at 3 mg powder mL−1 BFT-AqE. Across the 13 strains tested against L3, efficacy ranged from 0 to 75% exsheathment inhibition, and 17 to 92% L3 motility inhibition at a concentration of 25 mg powder mL−1 BFT-AqE. There was no correlation between the PAC content of BFT powders and the anti-parasitic activity of aqueous extracts, therefore other secondary compounds may have contributed to the observed anti-parasitic effects. Further testing of BFT using bioactivity-driven fractionation and screening of BFT populations for the identified anti-parasitic compounds is needed.

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Permana, I. G., Despal, A. Rosmalia et M. D. Rahayu. « Inclusion of Different Level Leucaena in Dairy Ration to Balance Rumen Degradable and Undegradable Protein Ratio ». IOP Conference Series : Earth and Environmental Science 1020, n^o 1 (1 avril 2022) : 012013. http://dx.doi.org/10.1088/1755-1315/1020/1/012013.

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Abstract Sustainability use of expensive protein source in a dairy ration requires ration formulation based on rumen degradable and undegradable protein ratio (RDUP). It improves the efficiency of microbial protein synthesis and less feed residue to the environment. Providing less expensive green protein sources such as leucaena (Leucaena leucocephala) is also an alternative. This study aimed to evaluate the effect of dairy ration based on RDUP with leucaena addition on in vitro fermentability and digestibility. This study was conducted in a 4 x 3 factorial randomized block design. Factor 1 was RDUP levels (R1= 60:40; R2= 55:45; R3= 50:50; R4= 45:55) and factor 2 was Leucaena addition (L1= 10%; L2= 20%; L3= 30%). The data were analyzed using ANOVA and followed by the Duncan test. The result showed that increasing RDUP levels increased NH3 concentration and dry matter digestibility. Treatment L2 resulted in a high NH3 concentration compared to other L treatments. The combination of R1 with L2 and L3 resulted in the highest total VFA concentration than other treatments. Protozoa population increased with increasing leucaena in the ration. It is concluded that dairy ration with 60:40 rumen degradable protein to undegradable protein ratio and 20% leucaena can improve ruminal fermentation and digestibility.

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Nazish, Asfa, Fozia, Baharullah Khattak, Taj Ali Khan, Ijaz Ahmad, Riaz Ullah, Ahmed Bari et al. « Antinematode Activity of Abomasum Bacterial Culture Filtrates against Haemonchus contortus in Small Ruminants ». Animals 11, n^o 6 (21 juin 2021) : 1843. http://dx.doi.org/10.3390/ani11061843.

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Haemonchosis is a parasitic disease of small ruminants that adversely affects livestock production. Haemonchus contortus is one of the most prevalent nematode parasites that infect the abomasum of small ruminants. This parasite reduces milk production, overall growth and sometimes causes the death of the infected animals. The evaluation of the biocontrol potential of some abomasum bacterial isolates against H. contortus is investigated in this study. Out of which, three isolates—Comamonas testosteroni, Comamonas jiangduensis, Pseudomonas weihenstephanesis—show significant effect against the nematode L3, adult, and egg hatch inhibition assays. Various concentrations of metabolites from these bacteria are prepared and applied in different treatments compared with control. In the case of adult mortality assay, 50% metabolites of C. testosteroni and P. weihenstephanesis show 46% adult mortality, whereas C. jiangduensis shows 40% mortality. It is observed that decreasing the concentration of bacterial metabolite, lowers nematode mortality. The minimum nematode mortality rate is recorded at the lowest filtrates concentration of all the bacterial isolates. The same trend is observed in egg hatch inhibition assay, where the higher concentration of bacterial culture filtrates shows 100% inhibition of H. contortus egg. It is concluded that the effect of bacterial culture filtrates against H. contortus is dose-dependent for their activity against nematode L3, adult, and inhibition of egg hatchment.

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Grønvold, J., J. Wolstrup, P. Nansen, M. Larsen, S. A. Henriksen, H. Bjørn, K. Kirchheiner, K. Lassen, H. Rawat et H. L. Kristiansen. « Biotic and abiotic factors influencing growth rate and production of traps by the nematode-trapping fungus Duddingtonia flagrans when induced by Cooperia oncophora larvae ». Journal of Helminthology 73, n^o 2 (février 1999) : 129–36. http://dx.doi.org/10.1017/s0022149x99000190.

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A series of experiments on corn meal agar was carried out to evaluate the efficacy of the nematode-trapping fungus Duddingtonia flagrans in different abiotic and biotic conditions which occur in cow pats. Above a concentration of 50 parasitic larvae (L3) cm–2 the fungus produced a maximum of between 500 and 600 nets cm–2 at 20°C in 2 days on the surface of corn meal agar. There were no differences in the trap-producing capacity of three strains of D. flagrans (CIII4, CI3 and Trol A). On agar at 30° and 20°C, the fungus responded to Cooperia oncophora L3 very quickly producing a maximum of trapping nets 1 day after induction. At 10°C, traps were produced slowly starting on day 4 after induction and continued over the following week. Duddingtonia flagrans (CI3) grew at a normal rate at least down to an oxygen concentration of 6 vol.% O2, but it did not grow anaerobically. On agar, D. flagrans (CI3) did not produce trapping nets in an anaerobic atmosphere. Moreover, C. oncophora L3 stopped migration under anaerobic conditions. When the fungal cultures were transferred to a normal aerobic atmosphere, after 1 and 2 weeks under anaerobic conditions, the C. oncophora L3 resumed migrating on the agar and, in response, D. flagrans produced traps in the same amount as when it had not been under anaerobic stress. Under microaerophilic conditions (6 vol.% O2) D. flagrans was able to grow, but the C. oncophora L3 were not able to induce trapping nets in D. flagrans (Trol A) because of larval immobility. But, as under anaerobic conditions, the fungus could return to a nematode-trapping state when transferred to a normal aerobic atmosphere within 1 or 2 weeks if migrating nematodes were present. Under natural conditions in the cow pat it is expected that the fungus will be ready to attack parasitic larvae, when the oxygen tension increases as a result of, for example the activity of the coprophilic fauna. Artificial light giving 3000–3400 Lux on the surface of the agar significantly depressed the growth rate and the production of trapping nets in D. flagrans (CI3). On agar, D. flagrans (CI3) could grow and produce trapping nets at pH levels of 6.3 to 9.3. Net-production has its optimum between pH 7 and 8. On dry faeces mycelial growth was 7–10 mm during a 15 day period while on moist faeces the fungus expanded 15–20 mm during the same period. Based on the parameters investigated, D. flagrans is expected to be especially active in the well aerated surface layer of a cow pat, an area which normally contains a high concentration of infective nematode parasite larvae, but also an area where the temperature can be high and the water content low.

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Grønvold, J., J. Wolstrup, P. Nansen, M. Larsen, S. A. Henriksen, H. Bjørn, K. Kirchheiner, K. Lassen, H. Rawat et H. L. Kristiansen. « Biotic and abiotic factors influencing growth rate and production of traps by the nematode-trapping fungus Duddingtonia flagrans when induced by Cooperia oncophora larvae ». Journal of Helminthology 73, n^o 2 (février 1999) : 129–36. http://dx.doi.org/10.1017/s0022149x00700319.

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A series of experiments on corn meal agar was carried out to evaluate the efficacy of the nematode-trapping fungus Duddingtonia flagrans in different abiotic and biotic conditions which occur in cow pats. Above a concentration of 50 parasitic larvae (L3) cm–2 the fungus produced a maximum of between 500 and 600 nets cm–2 at 20°C in 2 days on the surface of corn meal agar. There were no differences in the trap-producing capacity of three strains of D. flagrans (CIII4, CI3 and Trol A). On agar at 30° and 20°C, the fungus responded to Cooperia oncophora L3 very quickly producing a maximum of trapping nets 1 day after induction. At 10°C, traps were produced slowly starting on day 4 after induction and continued over the following week. Duddingtonia flagrans (CI3) grew at a normal rate at least down to an oxygen concentration of 6 vol.% O2, but it did not grow anaerobically. On agar, D. flagrans (CI3) did not produce trapping nets in an anaerobic atmosphere. Moreover, C. oncophora L3 stopped migration under anaerobic conditions. When the fungal cultures were transferred to a normal aerobic atmosphere, after 1 and 2 weeks under anaerobic conditions, the C. oncophora L3 resumed migrating on the agar and, in response, D. flagrans produced traps in the same amount as when it had not been under anaerobic stress. Under microaerophilic conditions (6 vol.% O2) D. flagrans was able to grow, but the C. oncophora L3 were not able to induce trapping nets in D. flagrans (Trol A) because of larval immobility. But, as under anaerobic conditions, the fungus could return to a nematode-trapping state when transferred to a normal aerobic atmosphere within 1 or 2 weeks if migrating nematodes were present. Under natural conditions in the cow pat it is expected that the fungus will be ready to attack parasitic larvae, when the oxygen tension increases as a result of, for example the activity of the coprophilic fauna. Artificial light giving 3000–3400 Lux on the surface of the agar significantly depressed the growth rate and the production of trapping nets in D. flagrans (CI3). On agar, D. flagrans (CI3) could grow and produce trapping nets at pH levels of 6.3 to 9.3. Net-production has its optimum between pH 7 and 8. On dry faeces mycelial growth was 7–10 mm during a 15 day period while on moist faeces the fungus expanded 15–20 mm during the same period. Based on the parameters investigated, D. flagrans is expected to be especially active in the well aerated surface layer of a cow pat, an area which normally contains a high concentration of infective nematode parasite larvae, but also an area where the temperature can be high and the water content low.

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David, Sophia, Joshua L. C. Wong, Julia Sanchez-Garrido, Hok-Sau Kwong, Wen Wen Low, Fabio Morecchiato, Tommaso Giani et al. « Widespread emergence of OmpK36 loop 3 insertions among multidrug-resistant clones of Klebsiella pneumoniae ». PLOS Pathogens 18, n^o 7 (11 juillet 2022) : e1010334. http://dx.doi.org/10.1371/journal.ppat.1010334.

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Mutations in outer membrane porins act in synergy with carbapenemase enzymes to increase carbapenem resistance in the important nosocomial pathogen, Klebsiella pneumoniae (KP). A key example is a di-amino acid insertion, Glycine-Aspartate (GD), in the extracellular loop 3 (L3) region of OmpK36 which constricts the pore and restricts entry of carbapenems into the bacterial cell. Here we combined genomic and experimental approaches to characterise the diversity, spread and impact of different L3 insertion types in OmpK36. We identified L3 insertions in 3588 (24.1%) of 14,888 KP genomes with an intact ompK36 gene from a global collection. GD insertions were most common, with a high concentration in the ST258/512 clone that has spread widely in Europe and the Americas. Aspartate (D) and Threonine-Aspartate (TD) insertions were prevalent in genomes from Asia, due in part to acquisitions by KP sequence types ST16 and ST231 and subsequent clonal expansions. By solving the crystal structures of novel OmpK36 variants, we found that the TD insertion causes a pore constriction of 41%, significantly greater than that achieved by GD (10%) or D (8%), resulting in the highest levels of resistance to selected antibiotics. We show that in the absence of antibiotics KP mutants harbouring these L3 insertions exhibit both an in vitro and in vivo competitive disadvantage relative to the isogenic parental strain expressing wild type OmpK36. We propose that this explains the reversion of GD and TD insertions observed at low frequency among KP genomes. Finally, we demonstrate that strains expressing L3 insertions remain susceptible to drugs targeting carbapenemase-producing KP, including novel beta lactam-beta lactamase inhibitor combinations. This study provides a contemporary global view of OmpK36-mediated resistance mechanisms in KP, integrating surveillance and experimental data to guide treatment and drug development strategies.

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Bada, A. A., I. B. Osho, S. O. Adewole et L. K. Olofintoye. « Anthelmintic effects of four medicinal plants using in vitro L3 larva stage ». Journal of Animal Science and Veterinary Medicine 7, n^o 3 (30 juin 2022) : 98–102. http://dx.doi.org/10.31248/jasvm2022.325.

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In vitro anthelminthic activity of Vernonia amygdalina, Ocimum grattissimum, Nicotiana tabacum and Talinum triangulare using L3 stage larva was investigated. Standard procedure was followed for larva culturing, preparation of extract and for in vitro assay. The concentration of Vernonia amygdalina was effective at 1.0 mg/ml at 1 and 2 hours, Ocimum grattissimum at 0.5 mg/ml at 1 hour, Nicotiana tabacum at 0.125 mg/ml at 1 hour and Talinum triangulare at 0.125 mg/ml at 2 hours. The result showed that there was anthelminthic activity in the four plants after 3 hours of the experiment. Nicotiana tabacum showed a faster anthelmintic effect at a lower concentration of 0.125 mg/l and at a lower hour (1 hour) while Talinum triangulare showed a slower anthelmintic effect compared to other medicinal plants at 2 hours. The health status of ruminants can be improved through the consumption of these four medicinal plants.

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Chen, Li Li, Zu Min Qiu, Zhen Zhong Huang et Yan Fen Wu. « Synthesis and Characterization of New Kinds Sulfoxide Extractants for Palladium(II) ». Advanced Materials Research 287-290 (juillet 2011) : 1841–46. http://dx.doi.org/10.4028/www.scientific.net/amr.287-290.1841.

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Three new extractants for palladium(II) extraction: bis(noctyl-Sulfinyl-ethyl) ether(L1), bis(isooctyl-Sulfinyl-ethyl)ether(L2), bis(isooctyl-Sulfinyl-ethoxy)ethane(L3) were synthesized. Micro-analytical data, elemental analysis, 1HNMR and IR-spectra were used to confirm the structures. Based on independent extraction experiments of Pd(II) , the extraction parameters of Pd(II) were studied in detail, and the optimal extraction parameters were obtained and summarized as the following: H+ concentration of aqueous phase 1.0-1.5 mo1·L-1, sulfoxide extractants concentration 0.01-0.1 mo1·L-1. The order of the extractability of the three extractants towards palladium(II) was L2>L3>L1. The coordination number was studied by the slope method. The results indicated that, in low acidity, the coordination number for extracting palladium (II) was 1.0 with all three extractants, while it was 2.0 in high acidity. FT-IR spectra was used to analyze the structure of the complex. Palladium (II) was coordinated with the oxygen atom in S=O group of the three extractants. and palladium (II) may also coordinated with the oxygen atom in C-O-C group of extractant L1, L2.

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Yang, C., H. C. Gibbs, L. Xiao et C. R. Wallace. « Prevention of pathophysiologic and immunomodulatory effects of gastrointestinal nematodiasis in calves by use of strategic anthelmintic treatments ». American Journal of Veterinary Research 54, n^o 12 (1 décembre 1993) : 2048–55. http://dx.doi.org/10.2460/ajvr.1993.54.12.2048.

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Summary Effects of strategic anthelmintic treatment on pathophysiologic and immunomologic changes induced by infection with Ostertagia ostertagi and Cooperia oncophora were studied in 2 groups, of 12 calves each: an infected group, inoculated with 200,000 mixed O ostertagi and C oncophora third-stage larvae (L3) on day 1; and an infected-treated group, similarly inoculated, but treated with ivermectin at 9 and 33 days. All calves were also inoculated at 12 weeks with Brucella abortus vaccine, at 13 weeks with bovine rhinotracheitis vaccine (bovine herpesvirus 1), and at 14 weeks with a soluble O ostertagi L3 extract, then were allowed to graze on a contaminated pasture. Four calves from each group were slaughtered at 7, 11, and 19 weeks of the study. Calves of the infected group had significantly (P < 0.05) lower weight gain than did those in the infected-treated group (60.90 kg vs 75.86 kg). They also had high plasma pepsinogen and serum gastrin values, and low serum albumin concentration from 2 or 4 weeks. Calves in the infected-treated group had steady weight gain and no significant changes in albumin and gastrin values. They also had less severe abomasal lesions and higher carcass yield. Compared with calves of the infected-treated group, those of the infected group had significantly (P < 0.05) lower blood lymphocyte reactivity to phytohemagglutinin at 14 and 16 weeks, to concanavalin A at 10 weeks, to pokeweed mitogen at 14 weeks, and to soluble O ostertagi L3 extract at 2, 4, and 14 weeks. They also had significantly (P < 0.05) lower IgG1 concentration to excretory-secretory an tigens of the fourth-stage larvae of O ostertagi at 13, 18, and 19 weeks. In addition, they had significantly (P < 0.05) higher total mean eosinophil count. Antibody responses to B abortus and bovine herpesvirus 1, however, were not different between the 2 groups.

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Gulland, F. M. D., et M. Fox. « Epidemiology of nematode infections of Soay sheep (Ovis aries L.) on St Kilda ». Parasitology 105, n^o 3 (décembre 1992) : 481–92. http://dx.doi.org/10.1017/s0031182000074667.

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SUMMARYThe epidemiology of nematode infections of Soay sheep on the island of St Kilda over a period of 2 years (August 1988–August 1990) spanning a host population crash is described. Infective larvae (L3) levels on pasture were high (2422±365 L3/kg D.M. grass in midsummer 1988) when host population density was high, decreasing after the sheep population declined by 70% in early 1989 (601 ±14 L3/kg D.M. in midsummer 1989). The availability of infective larvae to sheep increased during the winter of 1988–1989, probably as a result of concentration of existing larvae on grass as vegetation was destroyed by bad weather and overgrazing. Increased availability of pre-parasitic stages was accompanied by a marked increased in faecal egg counts from sheep of all ages and both sexes. Prevalence and intensity of infection (faecal egg counts) were higher in males than females throughout the 2-year study (χ2 = 208.3, P < 0.005 and F1.2000 = 304, P < 0.001 respectively), except during the lambing periods, and decreased with age in both sexes. Changes in prevalence and intensity of strongyle infections were associated with changes in host population density. Prevalence and intensity of Dictyocaulus filaria larvae in faeces increased during the host population crash. Infection intensity decreased with age (F1.203 = 44.02, P < 0.001) and was higher in males than females (F1.203 = 13.45, P < 0.001).

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Morris, O. N. « SUSCEPTIBILITY OF THE BERTHA ARMYWORM, MAMESTRA CONFIGURATA (LEPIDOPTERA : NOCTUIDAE), TO COMMERCIAL FORMULATIONS OF BACILLUS THURMGIENSIS VAR. KURSTAKI ». Canadian Entomologist 118, n^o 5 (mai 1986) : 473–78. http://dx.doi.org/10.4039/ent118473-5.

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AbstractCommercial Bacillus thuringiensis var. kurstaki (B.t.k.) (Dipel 132® and Thuricide 48 LV®) were bioassayed at 20 and 25°C against 3rd- (L3), 4th- (L4), 5th- (L5), and 6th- (L6) instar larvae of the bertha armyworm, Mamestra configurata Walker, on greenhouse-grown canola, Brassica napus L. cv. Westar. The L4 was the most susceptible stage to B.t.k. but it was much less susceptible than the spruce budworm, Choristoneura fumiferana (Clem.), a species against which this bacterium is currently used. The lethal time of B.t.k. to the larvae was inversely related to dosage applied. Younger instars (L3 to L4) were more sensitive to Dipel than older instars (L5 to L6) at 20°C but the reverse was true for Thuricide-treated larvae. All B.t.k. treatments reduced weight gain and frass deposition (by inference feeding activity) compared with untreated controls. The LC50 concentration of B.t.k. for larvae reduced survival to adult emergence by 87–100%.

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Boyko, O. O., et V. V. Brygadyrenko. « The Viability of Haemonchus Contortus (Nematoda, Strongylida) and Strongyloides Papillosus (Nematoda, Rhabditida) Larvae Exposed to Various Flavourings and Source Materials Used in Food Production ». Vestnik Zoologii 53, n^o 6 (1 décembre 2019) : 433–42. http://dx.doi.org/10.2478/vzoo-2019-0039.

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Abstract The objective of this study is to evaluate the viability of larval nematodes of ungulates under the infl uence of 14 fl avourings and source materials approved for use in and on foods. Minimum LD50 for L3 Strongyloides papillosus (Wedl, 1856) were observed when using Cinnamaldehyde, α-Terpineol and Benzyl alcohol, for L1–2 S. papillosus under the infl uence of Benzyl alcohol, Cinnamaldehyde, L-Linalool and Benzyl acetate, for L3 Haemonchus contortus (Rudolphi, 1803) under the influence γ-Undecalactone and Cinnamaldehyde. Ethyl acetate, β-Ionone и D-Limonene had the lowest effect on all the studied stages of development of the nematodes: larvae did not die during 24 hours even at 1 % concentration of these substances. Further experiments with usage of mixtures of the substances studied in this article will contribute to the development of preparations with a stronger effect on larvae of nematode parasites of the digestive system of vertebrate animals.

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Affat, Sajda, Saher Al – Shamkhawy et Denys Snigur. « Cloud Point Extraction Coupled to Flame Atomic Absorbance Spectroscopy for Cobalt (II) determination with Azo-Azomethine Dye ». University of Thi-Qar Journal of Science 11, n^o 1 (19 juin 2024) : 124–31. http://dx.doi.org/10.32792/utq/utjsci/v11i1.1207.

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The azo-azomethine dye 6,6'-((1E,1'E)-((4-methyl-1,2-phenylene)bis(azanylylidene))bismethanylylidene))bis(2-methoxy-3-(o-tolyldiazenyl) phenol) (L3) were synthesized and characterized by UV-visible, FT-IR, 1H-NMR and Mass spectroscopy. The effect of the several factors on the CPE pre-concentration of Cobalt (II) with L3 was optimized. Extensive thermodynamic study has been presented to understand the mechanism of extraction and solubilization of studied complex in Triton X-100 micelles. Under the optimized conditions, enrichment factor of 54 is achieved leading to limit of detection and limit of quantitation of 11.5 and 38.4 ngmL-1 respectively. Under the optimal conditions the calibration plot is linear in the range of 0.025-3 μg mL-1, the precision (RSD%; n=8) of the proposed method is of 0.823% at 0.05 μg mL-1 of Co (II). This method is applied to the determination of Co (II) in various environmental samples.

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Chan-Pérez, J. I., J. F. J. Torres-Acosta, R. I. Rodríguez-Vivas et S. L. Villegas-Pérez. « Reduction of benzimidazole resistance in established Haemonchus contortus populations in goats using a single infection with a benzimidazole-susceptible isolate ». Journal of Helminthology 89, n^o 5 (16 septembre 2014) : 641–45. http://dx.doi.org/10.1017/s0022149x14000674.

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AbstractAn in vivo study in goats evaluated the effect of superimposing a single artificial infection with a benzimidazole (BZ)-susceptible Haemonchus contortus isolate upon established H. contortus populations of known BZ resistance by measuring the phenotypic BZ resistance of eggs collected from faeces before and after re-infection. Two H. contortus isolates, one benzimidazole resistant (BZR) and the other susceptible (BZS), were used to infect worm-free goats. Eight goats were initially infected with 2000 third-stage larvae (L3). In each case the inoculum contained a pre-determined proportion of the two isolates: 100% BZS (one goat), 75% BZS/25% BZR (two goats), 50% BZS/50% BZR (two goats), 25%BZS/75% BZR (two goats) and, finally, 100% BZR (one goat). The phenotypic BZ susceptibility of the H. contortus population formed in each goat after the first infection was determined on days 30 and 36 post-infection using an egg-hatch assay (EHA) that estimated the concentration of thiabendazole (TBZ) required for 95% inhibition of larval hatching (EC95) with a 95% confidence interval (95% CI). On day 49 post-infection, goats were re-infected with 2000 L3 of the BZS isolate alone. A second set of EHA bioassays was performed 28 days and 34 days after re-infection. The first infection protocol produced three populations classified as BZS (EC95 0.055–0.065 μg TBZ/ml) while four were categorized as BZR (EC95 0.122–0.344 μg TBZ/ml). The status of one other population could not be determined. After re-infection with BZS L3, the number of susceptible populations increased to six (EC95 0.043–0.074 μg TBZ/ml) while the remaining two were deemed resistant (EC95 0.114–119 μg TBZ/ml). Re-infection with BZS L3 thereby reduced the resistance status of most H. contortus populations.

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Singh, U., J. Dong, C. Jian et K. K. Hazra. « Optimizing zinc foliar spray for zinc fortification and yield improvement in wheat ». Journal of Environmental Biology 43, n^o 5 (7 septembre 2022) : 739–45. http://dx.doi.org/10.22438/jeb/43/5/mrn-2016.

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Aim: To investigate the field efficacy of foliar applied Zn at variable doses and time of application for enriching Zn concentration in different milling fractions of wheat grain and Zn loading capacity of different grain milling fractions. Methodology: A field experiment was carried out involving four graded Zn sprays (0.1, 0.2, 0.3, and 0.4%) with water-spray as control, applied at flowering stage of wheat crop at weekly intervals.Harvested wheat grains were pearled into nine fractions from the surface to the center using two rice polishers (JNMJ7 and JNMJ6). The rice polishers were able to separate the wheat grain fractions. Zinc concentration in the whole grain and grain fractions (layer 1 to layer 9) of wheat samples were digested with di-acid mixture and estimated on an Atomic Absorption Spectrophotometer. Results: Foliar application of Zn (0.3-0.4% Zn) at 14 or 21 days after flowering (DAF) increased Zn in whole grain by 15.3-17.0 mg kg-1 (p < 0.05). Zn spray enhanced Zn concentration in all the grain layers i.e. 1st to 9th layers (L), albeit in endosperm layers (L3-L8) by a maximum of 10.8 mg kg-1. However, Zn loading capacity differed in different fractions and was in the order L8>L6>L7>L5≥ L4≥L3 (p < 0.05). Interpretation: Foliar spray of Zn in wheat with optimum dose (0.3-0.4%) and time (14-21 DAF) can enhance Zn acquisition and loading to grain endosperm with a higher yield. Key words: Foliar spray, Grain yield, Wheat, Zinc biofortification

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Hidayati, Sri, Natalia Gultom et Hestuti Eni. « OPTIMASI PRODUKSI METIL ESTER SULFONAT DARI METIL ESTER MINYAK JELANTAH ». Reaktor 14, n^o 2 (8 août 2012) : 165. http://dx.doi.org/10.14710/reaktor.14.2.165-172.

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OPTIMATION OF METHYL ESTER SULFONATES PRODUCTION FROM WASTE COOKING METHYL ESTER. An experiment of sulfonation process of methyl ester to produce methyl ester sulfonates (MES) was caried out using waste palm methyl ester and sulfuric acid as sulfonating agent with variation of H2SO4 concentration (60% (K1), 70% (K2), dan 80% (K3)) and sulfonation time (60 minute (L1), 75 minute (L2) and 90 minute (L3)) using factorial on Randomized Complete Design Block. The experiment result showed the best sulfonation condition present in 80% H2SO4 concentration and sulfonation time of 90 minutes. The best characteristic of MES is produced showed surface tension of 27.35 dyne/cm, emulsion stability of 89.44%, acid value of 17.72 mg KOH/g and interfacial tension of 0.0361 dyne/cm at MES concentration of 2% in 10,000 ppm salinity water. Sebuah penelitian tentang proses produksi metil ester sulfonat menggunakan minyak bekas kelapa sawit dilakukan dengan menggunakan H2SO4 sebagai agen pensulfonasi dengan variasi konsentrasi H2SO4 (60% (K1), 70% (K2), dan 80% (K3)) dan lama sulfonasi (60 menit (L1), 75 menit (L2) and 90 menit (L3)) dengan menggunakan faktorial dalam Rancangan Kelompok Teracak Lengkap. Hasil penelitian menunjukkan bahwa kondisi proses sulfonasi terbaik terdapat pada konsentrasi H2SO4 80% dan lama reaksi 90 menit. Karakteristik Metil Ester Sulfonat (MES) terbaik yang dihasilkan memperlihatkan nilai tegangan permukaan 27,35 dyne/cm, stabilitas emulsi 89,44%, nilai bilangan asam antara 17,72 mg KOH/g dan nilai tegangan antar muka pada konsentrasi MES 2% di dalam air dengan salinitas 10.000 ppm yaitu 0,0361 dyne/cm.

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Wang, Zhenzhen, Jianjun Zhao, Jiawen Xu, Mingrui Jia, Han Li et Shijun Wang. « Influence of Straw Burning on Urban Air Pollutant Concentrations in Northeast China ». International Journal of Environmental Research and Public Health 16, n^o 8 (17 avril 2019) : 1379. http://dx.doi.org/10.3390/ijerph16081379.

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Northeast China is China’s primary grain production base. A large amount of crop straw is incinerated every spring and autumn, which greatly impacts air quality. To study the degree of influence of straw burning on urban pollutant concentrations, this study used The Moderate-Resolution Imaging Spectroradiometer/Terra Thermal Anomalies & Fire Daily L3 Global 1 km V006 (MOD14A1) and The Moderate-Resolution Imaging Spectroradiometer/Aqua Thermal Anomalies and Fire Daily L3 Global 1 km V006 (MYD14A1) data from 2015 to 2017 to extract fire spot data on arable land burning and to study the spatial distribution characteristics of straw burning on urban pollutant concentrations, temporal variation characteristics and impact thresholds. The results show that straw burning in Northeast China is concentrated in spring and autumn; the seasonal spatial distributions of PM2.5, PM10 andAir Quality Index (AQI) in 41 cities or regions in Northeast China correspond to the seasonal variation of fire spots; and pollutants appear in the peak periods of fire spots. In areas where the concentration coefficient of rice or corn is greater than 1, the number of fire spots has a strong correlation with the urban pollution index. The correlation coefficient R between the number of burned fire spots and the pollutant concentration has a certain relationship with the urban distribution. Cities are aggregated in geospatial space with different R values.

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Tchegueni, Matotiloa, Komi Agboka, Atti Tchabi, Lankondjoa Kolani, Manguilibè Tchao et Agbéko K. Tounou. « Insecticidal effect of Jatropha curcas L. Oil on Spodoptera frugiperda (Smith) (Lepidoptera:Noctuidae) ». Asian Journal of Agricultural and Horticultural Research 10, n^o 3 (8 mars 2023) : 9–18. http://dx.doi.org/10.9734/ajahr/2023/v10i3227.

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The study was undertaken to contribute to the sustainable management of Spodoptera frugiperda Smith on maize. It aims to evaluate the insecticidal efficacy of Jatropha curcas L. oil on S. frugiperda larvae. Two concentrations of J. curcas oil (10 and 20ml.l-1) were tested by ingestion on the six larval stages of S. frugiperda grouped into (L1-2 (3-5 days of age); L3-4 (6-8 days of age); L5-6 (>10 days of age)). The insecticidal efficacy of the oil was determined in the laboratory and the phytosanitary protection tests on maize were carried out in the field. In the laboratory, the concentration of 10 ml.l-1 with/without emulsifier caused a mortality rate of (87-92%) at stage L1-2, (51-58%) at stage L3-4, and (57- 68%) at L5-6 stage after 72 hours of ingestion. Concentration of 20 ml.l-1 caused over 70% mortality whether applied with or without an emulsifier at all stages. Adult emergence was nil for L1-2 stages at 20 ml.l-1 and <10% for the other stages. Plots subjected to jatropha oil treatments (2l.ha-1 and 4l.ha-1 with or without emulsifier) were less infested like the plots treated with Emamectine benzoate (Emacot) compared to control plots untreated. The present results indicated that jatropha oil has insecticidal potential against S. frugiperda.

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Mezyk, Stephen P., et David A. Armstrong. « Kinetics of oxidation of Cu(I) complexes of cysteine and penicillamine : nature of intermediates and reactants at pH 10.0 ». Canadian Journal of Chemistry 67, n^o 4 (1 avril 1989) : 736–45. http://dx.doi.org/10.1139/v89-112.

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The Cu(I)•L2 complex with cysteine ligands at total Cu(I) concentrations of 10–30 μM was shown to be oxidised by cysteinyl radicals (RS•) with a diffusion-controlled rate constant k11a = 1.8 × 109 M−1 s−1. The corresponding reaction with the cysteine disulphide anion (RS•—SR−) proceeded at a slower rate, k11b = 2.7 × 108 M−1s−1. At higher Cu(I) concentrations, a slow and a fast component of absorption growth was observed. The slow component rate was independent of Cu(I) concentration, but it became more intense as the Cu(I) concentration rose. The yields and kinetic data were shown to be consistent with the presence of an equilibrium between the Cu(I)•L2 species and a second Cu(I) complex, Cu(I)2•L3, with an equilibrium constant of K1 = 162.[Formula: see text]This finding is consistent with the earlier work of Bagiyan etal. The rate constant of the oxidation of Cu(I)2•L3 by the cysteinyl radical was k12 = 1.0 × 109 M−1 s−1. Similar results were obtained with penicillamine, except the rate constants and equilibrium constant were smaller, (k11a = 4.5 × 108 M−1 s−1, k11b < 2 × 108 M−1 s−1, k12 = 5.5 × 108 M−1 s−1 and K1 = 113). This was attributed to the presence of the β-methyl groups in penicillamine, which exert a large steric effect.The ultraviolet spectra of the long-lived products, which are stable on a millisecond timescale, was consistent with a Cu(II)•L2 structure with a square planar geometry. The oxidation of the Cu(I)2.L3 species proceeded via intermediates, which relaxed to the final product spectra with rate constants of k13b = 2.6 and 1.1 × 104 s−1 for cysteine and penicillamine, respectively. Comparison of the spectra of the intermediates with published data showed that they were consistent with the presence of a bridging thiolate ligand between Cu(I) and Cu(II). Keywords: oxidation, copper, mixed valence, cysteine, penicillamine, complexation.

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Ochędzan-Siodłak, Wioletta, Dawid Siodłak, Aleksandra Piontek et Karel Doležal. « Titanium and Vanadium Catalysts with 2-Hydroxyphenyloxazoline and Oxazine Ligands for Ethylene-Norbornene (co)Polymerization ». Catalysts 9, n^o 12 (8 décembre 2019) : 1041. http://dx.doi.org/10.3390/catal9121041.

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A series of titanium and vanadium complexes with oxazoline 2-(4,5-dihydro-1,3-oxazol-2-yl)phenol (L1), 2-(4-methyl-4,5-dihydro-1,3-oxazol-2-yl)phenol (L2), and oxazine 2-(5,6-dihydro-4H-1,3-oxazin-2-yl)phenol (L3) ligands were synthesized, and their structures were determined by NMR and MS methods as (L)2MtCl2. The vanadium complexes were found to be highly active in ethylene (7300 kgPE/(molV·h)) and ethylene/norbornene (5300 kgCop/(molV·h)) (co)polymerization. The polyethylene characteristics were melting temperature (123–142 °C), crystallinity degree (49–75%), molecular weight (5.7–8.5 × 105 g/mol), molecular weight distribution (1.5–2.4). The ethylene-norbornene (E-NB) copolymer characteristics were molecular weight (2.6–0.9 × 105 g/mol), molecular weight distribution (1.6–2.2), glass transition temperature (4–62 °C), norbornene incorporation (12.3–30.1 mol%) at initial concentration (0.5–1.5 mol/L). The microstructure of E-NB copolymers depends on the catalyst applied with the highest diads content for the (L3)2VCl2 and triads for the (L2)2VCl2 complexes.

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Vargas, Edgar, et Giselle Abarca. « Relación entre el estrés y las bacterias entomopatógenas Pantoea (Erwinia) agglomerans (herbicola) y Bacillus cereus en jobotos (Col : Melolonthidae) (Phyllophaga spp., Anomala spp. y Cyclocephala spp.), en Costa Rica. » Agronomía Mesoamericana 9, n^o 2 (30 mai 2016) : 25. http://dx.doi.org/10.15517/am.v9i2.19466.

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Concentrations of Colony Forming Units (CFU) were determined for two entomopathogenic bacteria (Pantoea agglomerans and Bacillus cereus), at the egg, larval, pupal, and adult stages of agriculturally important Phyllophaga and Cyclocephala white grubs, which were collected in five agroecosystems in Costa Rica. L2 and L3 larvae of Phyllophaga elenans collected in all regions where the study was conducted were extensive carriers of Pantoea agglomerans and Bacillus cereu. L2 and L3 larvae of Phyllophaga obsoleta, Phyllophaga menetriesi, Cyclocephala sanguinicollis and Cyclocephala castaniella found in the Central Valley and Central Pacific regions were carriers of Pantoea agglomerans and Bacillus cereus bacteria. In 60% to 90% of larvae in all white grub varieties studied, Pantoea agglomerans showed greater concentrations of CFU than Bacillus cereu, which showed the lowest CFU concentration. Egg, pupal, and adult mortality in all Phyllophaga species was due to Pantoea agglomerans in 62%, 80% and 22.5% of the cases, respectively. A possible antagonistic interaction between Pantoea agglomerans and Bacillus cereus is also discussed. In general, it was noted that light and larval manipulation were the main stress factors affecting these scarabids.

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Sengupta, Anirban, Mohammad Azharuddin, Maria E. Cardona, Claudia Devito, Eleanore von Castelmur, Anna Wehlin, Zuzanna Pietras et al. « Intranasal Coronavirus SARS-CoV-2 Immunization with Lipid Adjuvants Provides Systemic and Mucosal Immune Response against SARS-CoV-2 S1 Spike and Nucleocapsid Protein ». Vaccines 10, n^o 4 (24 mars 2022) : 504. http://dx.doi.org/10.3390/vaccines10040504.

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In this preclinical two-dose mucosal immunization study, using a combination of S1 spike and nucleocapsid proteins with cationic (N3)/or anionic (L3) lipids were investigated using an intranasal delivery route. The study showed that nasal administration of low amounts of antigens/adjuvants induced a primary and secondary immune response in systemic IgG, mIL-5, and IFN-gamma secreting T lymphocytes, as well as humoral IgA in nasal and intestinal mucosal compartments. It is believed that recipients will benefit from receiving a combination of viral antigens in promoting a border immune response against present and evolving contagious viruses. Lipid adjuvants demonstrated an enhanced response in the vaccine effect. This was seen in the significant immunogenicity effect when using the cationic lipid N3. Unlike L3, which showed a recognizable effect when administrated at a slightly higher concentration. Moreover, the findings of the study proved the efficiency of an intranasally mucosal immunization strategy, which can be less painful and more effective in enhancing the respiratory tract immunity against respiratory infectious diseases.

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Arango-De-la Pava, Luis David, Manasés González-Cortazar, Alejandro Zamilpa, Jorge Alfredo Cuéllar-Ordaz, Héctor Alejandro de la Cruz-Cruz, Rosa Isabel Higuera-Piedrahita et Raquel López-Arellano. « Understanding Artemisia cina Ethyl Acetate Extract’s Anthelmintic Effect on Haemonchus contortus Eggs and L3 Larvae : The Synergism of Peruvin Binary Mixtures ». Pathogens 13, n^o 6 (16 juin 2024) : 509. http://dx.doi.org/10.3390/pathogens13060509.

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Haemonchus contortus, a blood-feeding parasite in grazing sheep, causes economic losses. Drug resistance necessitates exploring plant-based anthelmintics like Artemisia cina (Asteraceae). The plant, particularly its ethyl acetate extract, shows anthelmintic activity against H. contortus. However, there is limited information on pharmacodynamic interactions in ethyl acetate compounds. The study aims to identify pharmacodynamic interactions in the ethyl acetate extract of A. cina with anthelmintic effects on H. contortus eggs and L3 larvae using binary mixtures. Bioactive compounds were isolated via chromatography and identified using spectroscopic techniques. Pharmacodynamic interactions were assessed through binary mixtures with a main compound. Four bioactive compounds were identified: 1-nonacosanol, hentriacontane, peruvin, and cinic acid. Binary mixtures, with peruvin as the main compound, were performed. Peruvin/1-nonacosanol-hentriacontane and peruvin/cinic acid mixtures demonstrated 1.42-fold and 4.87-fold increased lethal effects in H. contortus L3 infective larvae, respectively, at a 0.50LC25/0.50LC25 concentration. In this work, we determined the synergism between bioactive compounds isolated from the ethyl acetate extract of A. cina and identified unreported compounds for the specie.

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Choi, Yong Gyu, Kee-Sun Sohn, Kyong Hon Kim et Hee Dong Park. « Tb L3-edge X-ray Absorption Near-edge Structure Spectroscopic Analysis of Terbium-doped Phosphor Compoundsfor Plasma Display Panel Applications ». Journal of Materials Research 17, n^o 1 (janvier 2002) : 31–35. http://dx.doi.org/10.1557/jmr.2002.0007.

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We have analyzed Tb L3-edge x-ray absorption near-edge structure spectra of Tb-doped phosphor compounds for plasma display panel applications. Intensity and lifetime of the green emission from the Tb3+:5D4→7F5 transition were measured with respect to nominal terbium concentration in the host compounds, i.e., YBO3, YPO4,and Y4Al2O9, all of which were made through the solid-state reaction. Typical concentration quenching was evident on the fluorescence intensity and the fluorescing level lifetime in our samples. From the analyses of white line absorption peaks at TbL3-edge, it was verified that terbium is essentially trivalent in all the samples, even invery highly concentrated ones. Thus, this implies that the concentration quenching was not caused by presence of mixed-valent states of terbium. Instead, it is believed that anonradiative energy transfer route among Tb3+ ions might be responsible for thebehavior.

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Li, Kangrong, Pan Gong, Yongbin Zhang, Minji Liu, Zinan Zhang, Xiaoyu Yu, Mingmei Ye et Li Tian. « Effects of visceral adipose tissue on anti-tumour necrosis factor-α in Crohn’s disease ». Therapeutic Advances in Gastroenterology 16 (janvier 2023) : 175628482311719. http://dx.doi.org/10.1177/17562848231171962.

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Background: It remains unclear whether visceral adipose tissue (VAT) can predict the response of patients with Crohn’s disease (CD) to anti-tumour necrosis factor-α (anti-TNF-α) therapy. Objectives: This study aimed to investigate whether VAT predicts the efficacy of infliximab (IFX) for different sites of CD and its relationship with serum TNF-α levels and IFX serum trough concentration. Design: This is a multicentre retrospective study. Methods: Patients with CD treated with IFX from January 2014 to January 2021 were included. The perimeter of the visceral adipose area was obtained by a Computed Tomography (CT) scan. Participants were classified according to the lesion site (L1, L2, and L3) and visceral fat area. The participants were divided into colon-uninvolved non-visceral obesity (L1-VATL), colon-uninvolved visceral obesity (L1-VATH), colon-involved non-visceral obesity (L2 + L3-VATL), and colon involved visceral obesity (L2 + L3-VATH) groups. The end points of this study were set as disease remission status at 6 and 12 months. Results: The final cohort included 140 patients. Regarding efficacy at 6 and 12 months, there was a significant difference between L1-VATL (73.8% versus 36.8%, p = 0.006) and L1-VATH (81.0% versus 47.4%, p = 0.008) groups. In the analysis of serum TNF-α levels and IFX serum trough concentrations, there was a significant difference between L1-VATL and L1-VATH (59.5 pg/mL versus 236.0 pg/mL, pTNF-α = 0.006), (10.0 μg/mL versus 0.4 μg/mL, pIFX = 0.000), and L1-VATH and L2 + L3-VATH (78.7 pg/mL versus 118.6 pg/mL, pTNF-α = 0.031), (0.4 μg/mL versus 6.40 μg/mL, pIFX = 0.017). Conclusion: In L1 patients, the VAT level predicted the efficacy of IFX, with high VAT values indicating poor efficacy. The VAT level may be a useful radiological marker to predict the efficacy of IFX in patients with various types of CD.

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Iflijar, S. Wajizah et Samadi. « Rumen metabolic activities of cacao (Theobroma cacao L.) pod husk fermented with lingzhi mushroom (Ganoderma lucidum) at different concentration and incubation time ». IOP Conference Series : Earth and Environmental Science 922, n^o 1 (1 novembre 2021) : 012038. http://dx.doi.org/10.1088/1755-1315/922/1/012038.

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Abstract Cacao pod husk is a potential tropical resources that is widely utilized as animal feed. The presented study aimed to investigate rumen metabolic activities of (Theobroma cacao L.) pod husk fermented with lingzhi mushroom (Ganoderma lucidum) at different concentration and incubation time. A completely randomized factorial was applied in this study consisting of two factors; lingzhi mushroom concentration (K1 = 7.5%; K2 = 15%) and incubation time (L1 = 15 d; L2 =30 d; L3 = 45 d) with 3 replicates. All samples of cacao pod husk were analyzed to determine NH3 concentration, volatile fatty acid (VFA) concentration and gas production. Gas production was periodically collected at 2, 4, 6, 8, 10,12, 24, 48 and 72 h after incubation. The result of study indicated that there was significant interaction (P<0.01) between the concentration of G.lucidum and incubation time on NH3 concentration of rumen liquid. The highest concentration of NH3 was found at 7.5% G.lucidum concentration for 45 d incubation (14.70mM). G.lucidum concentration significantly affected (P<0.01) VFA concentration in which samples inoculated with the level of 7.5% G.lucidum was higher compared to that of 15% G.lucidum (125.16 mM vs 113.94 mM). This study concluded that cacao pod husk fermented with lingzhi mushroom at different concentration time influencing metabolic activities of the rumen.

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Ulanova, T. S., O. V. Gileva, E. V. Stenno et G. A. Veikhman. « Peculiarities of vanadium determination in whole blood by icp-ms ». Biomeditsinskaya Khimiya 60, n^o 1 (janvier 2014) : 109–14. http://dx.doi.org/10.18097/pbmc20146001109.

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The parameters of vanadium determination by ICP-MS in whole blood are presented. Conditions for blood sample preparation to reduce measure errors and to determine vanadium at the reference concentration level were optimized. The accuracy of the results is confirmed by analysis of standard blood samples Seronorm L1, L2 and L3. Vanadium mean in whole blood for the group of children from the town of Chusovoy (n=80) was 1.29±0.45 µg/L, and vanadium mean for grown – ups from the town of Chusovoy was 1.63±0.25 µg/L.

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Yaroslavtsev, Alexander A., Alexey P. Menushenkov, Olga V. Grishina, Roman V. Chernikov et Anatoly G. Kuchin. « Interplay between Local Electronic Structure, Crystalline Structure and Magnetic Ordering in Intermetallic Compounds Ce₂Fe_17−xMn_x ». Solid State Phenomena 190 (juin 2012) : 251–54. http://dx.doi.org/10.4028/www.scientific.net/ssp.190.251.

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For the first time the rearrangement of cerium local environment in Ce2Fe17-xMnx(x = 0; 1; 2) intermetallics vs. Mn concentration and temperature was investigated by thespectroscopy of extended X-ray absorption fine structure (EXAFS) above K-Ce absorptionedge. At the same time under similar conditions by the spectroscopy of X-ray absorption near-edge structure (XANES) above L3-Ce absorption edge the valence state of Ce was studied. Thecorrelation is found between changes in local electronic and crystalline structure observed inCe2Fe17-xMnx and the types of magnetic states in these compounds.

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Wang, Hui-Nan, Pei-Hua Wang, Zi-Ye Yang, Gui-Mei Zhang, Meng-Yu Chen, Ming-Rui Jiang, Zhu-Zhu Yue et al. « Comparison of Pharmacokinetics and Tissue Distribution Characteristics of Three Diterpenoid Esters in Crude and Prepared Semen Euphorbiae ». Evidence-Based Complementary and Alternative Medicine 2021 (16 août 2021) : 1–11. http://dx.doi.org/10.1155/2021/7402120.

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Background. Semen Euphorbiae (SE) and Semen Euphorbiae Pulveratum (SEP) have a long history of medicinal use. SEP is the processed product of SE; both ancient and modern studies have shown that SEP has a lower toxicity compared to SE. To clarify the influence of processing on the pharmacological properties of SE and SEP, a study was carried out to compare the pharmacokinetics and distribution characteristics of three active compounds after oral administration of SE and SEP extracts. Methods. A UPLC-MS/MS method was established to simultaneously determine the contents of Euphorbia factors L1, L2, and L3 in rat plasma and mouse tissues after an oral administration of crude and processed SE with approximately the same dosage. Plasma and heart, liver, spleen, lung, kidney, and colon tissue samples were treated with ethyl acetate and separated by gradient elution on a C18 column with a mobile phase of 0.1% formic acid and methanol. Results. The established method had good selectivity, linear range, accuracy, precision, stability, matrix effect, and extraction recovery. The area under the concentration time curve, time to maximum concentration, maximum concentration, half-life of elimination, and mean retention time of plasma samples in SEP-treated group decreased, and the clearance in SEP-treated group increased. Moreover, the active component concentrations in colon, liver, and kidney tissues were more followed by those in the heart, lungs, and spleen. Conclusion. These results indicate that the processing could influence the pharmacokinetics and tissue distribution of Euphorbia factors L1, L2, and L3 after oral administration of crude and processed SE. The data obtained may lay a foundation for the clinical use of SE and for further study on the processing mechanism of SE.

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SURES, B., K. KNOPF et W. KLOAS. « Induction of stress by the swimbladder nematode Anguillicola crassus in European eels, Anguilla anguilla, after repeated experimental infection ». Parasitology 123, n^o 2 (31 juillet 2001) : 179–84. http://dx.doi.org/10.1017/s003118200100823x.

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The purpose of this study was to determine under laboratory conditions over a period of 311 days if infection with the nematode Anguillicola crassus induces stress in European eels (Anguilla anguilla), and stimulates the endocrine stress axis as measured by serum cortisol levels. Eels were experimentally infected with 3rd-stage larvae (L3) in different doses to simulate natural conditions with varying infection pressures. Blood samples were drawn from the caudal vein every 2 weeks and serum cortisol concentrations were determined by radioimmunoassay (RIA). The results showed that the application of L3 resulted in a significant increase in the cortisol levels. The period of time at which elevated cortisol values were observed was consistent with the time of larval development and the appearance of adult A. crassus. Thus, there is a stress response to the larval and young adult stages, but no chronic response to older adults. Therefore, it is likely that infection of eels under natural conditions especially with a high number of larvae may be a considerable stressor, in combination with different environmental factors like water temperature, pH, oxygen concentration, pollution and inter-individual relationships.

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