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91.
Journal of Plant Research - The mildew locus O (Mlo) gene family is ubiquitous in land plants. Some members of this gene family are involved in negative regulation of powdery mildew resistance,...  相似文献   
92.
Barley plants (Hordeum vulgare L.) received foliar applications of 10?4 M gibberellic acid (GA3) and Kinetin (KN) individually and in combination at one or more of three growth stages: flag leaf appearance (I), ear emergence (II), and the first stage of senescence initiation in the flag leaf (III). Both plant growth regulators (PGR) hastened onset of senescence when sprayed at Stage I and/or Stage II. Treatment at Stage III, either alone or in combination with treatments at the other stages, tended to postpone senescence. Yield components also showed stage-dependent response: Stage I treatment increased the formation of total and bearing tillers, and Stage III treatment improved grain number and weight. However, while GA3 proved more effective than KN, the two together acted antagonistically.  相似文献   
93.
Mj-AMP2, a knottin-type antimicrobial peptide, in vitro inhibits the growth of several plant pathogenic fungi including Magnaporthe oryzae. We demonstrate that transgenic rice (Oryza sativa L.) plants expressing the Mj-AMP2 gene show enhanced resistance to M. grisea, the causal agent of the rice blast disease. Mj-AMP2 was efficiently expressed and the level of Mj-AMP2 ranged from 0.32% to 0.38% of the total protein in the transgenic rice plants. In vitro inhibitory activity assays with the crude protein extract from transgenic rice indicated that the Mj-AMP2 protein produced was biologically active. Constitutive expression of Mj-AMP2 in transgenic rice reduces the growth of M. grisea by 63% with respect to untransformed control plant, and no effect on plant phenotype was observed. Transgene expression of Mj-AMP2 gene was not accompanied by an induction of pathogenesis-related (PR) gene expression indicating that the transgene product itself is directly active against the pathogen. The results presented in this study suggest that the Mj-AMP2 gene could be a useful candidate for protection of rice plants against the rice blast fungus M. grisea.  相似文献   
94.
Genome-wide association analysis in populations of European descent has recently found more than a hundred genetic variants affecting risk for common disease. An open question, however, is how relevant the variants discovered in Europeans are to other populations. To address this problem for cardiovascular phenotypes, we studied a cohort of 4,464 African Americans from the Jackson Heart Study (JHS), in whom we genotyped both a panel of 12 recently discovered genetic variants known to predict lipid profile levels in Europeans and a panel of up to 1,447 ancestry informative markers allowing us to determine the African ancestry proportion of each individual at each position in the genome. Focusing on lipid profiles—HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C), and triglycerides (TG)—we identified the lipoprotein lipase (LPL) locus as harboring variants that account for interethnic variation in HDL-C and TG. In particular, we identified a novel common variant within LPL that is strongly associated with TG (p=2.7×10−6) and explains nearly 1% of the variability in this phenotype, the most of any variant in African Americans to date. Strikingly, the extensively studied “gain-of-function” S447X mutation at LPL, which has been hypothesized to be the major determinant of the LPL-TG genetic association and is in trials for human gene therapy, has a significantly diminished strength of biological effect when it is found on a background of African rather than European ancestry. These results suggest that there are other, yet undiscovered variants at the locus that are truly causal (and are in linkage disequilibrium with S447X) or that work synergistically with S447X to modulate TG levels. Finally, we find systematically lower effect sizes for the 12 risk variants discovered in European populations on the African local ancestry background in JHS, highlighting the need for caution in the use of genetic variants for risk assessment across different populations.  相似文献   
95.
Prestaining of human serum proteins with a new reactive dye Drimarene Brilliant Blue (DBB), was standardized employing 940 separations and examining 30 variables. Under the critical condition, the serum and the soluble dye (0.1 g/100 ml in working Tris-glycine buffer, pH, 8.3), was mixed in equal proportion, conjugate warmed at 40 degrees C for 2 hr and a 30 microliter of the sample electrophoresed by disc electrophoresis. The method when compared with prestaining by Remazol Brilliant Blue (RBB) and postelectrophoretic staining by Amido Black (AB) in 50 normal sera, revealed that the discs stained with DBB were intense and well defined and appeared in 2 hr on a sparkingly clear gel. Quality of resolution was better than RBB and AB. Protein bands eluted from the DBB prestained gels retained their immunoreactivity. The dye-protein complex of albumin and transferrin produced high-titre monospecific antisera in rabbits.  相似文献   
96.
Summary Conidia of Penicillium urticae were immobilized in Kappa-Carrageenan beads (2–3 mm) by a previously described procedure to yield an in situ grown immobilized cell population which could be induced to produce the antibiotic and mycotoxin, patulin. When repeatedly transferred into a nitrogen-free production medium every 2 days, the patulin productivity of these cells gradually decreased to 50% within 14 days while the total cell protein remained constant. This decline was due to the gradual loss of the cells' catalytic capacity for converting glucose to 6-methylsalicylic acid (6-MSA), the first metabolite of the patulin pathway, as well as for converting 6-MSA to patulin. When these 14 day-old cells were incubated in a nutrient rich growth medium for 2 days their patulin producing activity increased from 50% to 130%. On the other hand the addition of a protein synthesis inhibitor, cycloheximide, to the N-free production medium drastically reduced the patulin producing activity of the immobilized cells; in particular, their capacity for converting 6-MSA to patulin. The cells' patulin producing activity was maintained at >100% for longer than 15 days when the cells were repeatedly transferred into a yeast extract supplemented production medium or when they were occasionally transferred into 10 or 20% strength growth medium. Repeated transfers to a 10% strength growth medium appeared to stabilize the cells' capacity for converting 6-MSA to patulin.  相似文献   
97.
Rabies is a vaccine-preventable fatal zoonotic disease. Uganda, through the veterinary surveillance system at National Animal Disease Diagnostics and Epidemiology Centre (NADDEC), captures animal bites (a proxy for rabies) on a monthly basis from districts. We established trends of incidence of animal bites and corresponding post-exposure prophylactic anti-rabies vaccination in humans (PEP), associated mortality rates in humans, spatial distribution of animal bites, and pets vaccinated during 2013–2017. We reviewed rabies surveillance data at NADDEC from 2013–2017. The surveillance system captures persons reporting bites by a suspected rabid dog/cat/wild animal, human deaths due to suspected rabies, humans vaccinated against rabies, and pets vaccinated. Number of total pets was obtained from the Uganda Bureau of Statistics. We computed incidence of animal bites and corresponding PEP in humans, and analyzed overall trends, 2013–2017. We also examined human mortality rates and spatial distribution of animal bites/rabies and pets vaccinated against rabies. We identified 8,240 persons reporting animal bites in Uganda during 2013–2017; overall incidence of 25 bites/ 100,000population. The incidence significantly decreased from 9.2/100,000 in 2013 to 1.3/100,000 in 2017 (OR = 0.62, p = 0.0046). Of the 8,240 persons with animal bites, 6,799 (82.5%) received PEP, decreasing from 94% in 2013 to 71% in 2017 (OR = 0.65, p<0.001). Among 1441 victims, who reportedly never received PEP, 156 (11%) died. Western region had a higher incidence of animal bites (37/100,000) compared to other regions. Only 5.6% (124,555/2,240,000) of all pets in Uganda were vaccinated. There was a decline in the reporting rate (percentage of annual district veterinary surveillance reports submitted monthly to Commissioner Animal Health by districts) of animal bites. While reported animal bites by districts decreased in Uganda, so did PEP among humans. Very few pets received anti-rabies vaccine. Evaluation of barriers to complete reporting may facilitate interventions to enhance surveillance quality. We recommended improved vaccination of pets against rabies, and immediate administration of exposed humans with PEP.  相似文献   
98.
99.
Mutations of the glycine residue at the amino terminus of HA2 have been shown to have a large effect on the fusion activity of HA2, the extent of which apparently correlates with the side chain bulkiness of the substituting amino acids. To investigate into the cause of abrogation in fusogenicity and virus-promoted fusion mechanism, we synthesized several peptides in which this glycine was substituted by serine, glutamic acid, or lysine. 1,2-Dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and 1,2-dimyristoyl sn-glycero-3-phosphoglycerol (DMPG) were used as model membranes in the fluorescence, circular dichroism (CD), and FTIR measurements while sodium dodecyl sulfate was used in NMR studies. We found that, for the less active variants, affinity to membrane, degree of solvent dehydration, lipid perturbation, depth of insertion, and helicity were less. Comparison of affinity to membrane bilayer among these analogs revealed that binding of the fusion peptide is determined largely by the hydrophobic effect. Additionally, the orientation is closer to the membrane normal for the wild-type fusion peptide in the helix form while the inactive analogs inserted more parallel to the membrane surface.  相似文献   
100.
The extent of absorption of dietary advanced glycation end products (AGEs) is not fully known. The possible physiological impact of these absorbed components on inflammatory processes has been studied little and was the aim of this investigation. Aqueous solutions of bovine casein and glucose were heated at 95°C for 5 h to give AGE‐casein (AGE‐Cas). Simulated stomach and small intestine digestion of AGE‐Cas and dialysis (molecular mass cutoff of membrane = 1 kDa) resulted in a low molecular mass (LMM) fraction of digestion products, which was used to prepare bovine serum albumin (BSA)‐LMM‐AGE‐Cas complexes. Stimulation of human microvascular endothelial cells with BSA‐LMM‐AGE‐Cas complexes significantly increased mRNA expression of the receptor of AGE (RAGE), galectin‐3 (AGE‐R3), tumor necrosis factor alpha, and a marker of the mitogen‐activated protein kinase pathway (MAPK‐1), as well as p65NF‐κB activation. Cells treated with LMM digestion products of AGE‐Cas significantly increased AGE‐R3 mRNA expression. Intracellular reactive oxygen species production increased significantly in cells challenged with BSA‐LMM‐AGE‐Cas and LMM‐AGE‐Cas. In conclusion, in an in vitro cell system, digested dietary AGEs complexed with serum albumin play a role in the regulation of RAGE and downstream inflammatory pathways. AGE‐R3 may protect against these effects. © 2009 Wiley Periodicals, Inc. J Biochem Mol Toxicol 23:364–372, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20301  相似文献   
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