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131.
We describe a simple colony overlay procedure for peptidases (COPP) for the rapid fluorogenic detection and quantification of Vibrionaceae from seawater, shellfish, sewage, and clinical samples. The assay detects phosphoglucose isomerase with a lysyl aminopeptidase activity that is produced by Vibrionaceae family members. Overnight cultures are overlaid for 10 min with membranes containing a synthetic substrate, and the membranes are examined for fluorescent foci under UV illumination. Fluorescent foci were produced by all the Vibrionaceae tested, including Vibrio spp., Aeromonas spp., and Plesiomonas spp. Fluorescence was not produced by non-Vibrionaceae pathogens. Vibrio cholerae strains O1, O139, O22, and O155 were strongly positive. Seawater and oysters were assayed, and 87 of 93 (93.5%) of the positive isolates were identified biochemically as Vibrionaceae, principally Vibrio vulnificus, Vibrio parahaemolyticus, Aeromonas hydrophila, Photobacterium damselae, and Shewanella putrefaciens. None of 50 nonfluorescent isolates were Vibrionaceae. No Vibrionaceae were detected in soil, and only A. hydrophila was detected in sewage. The COPP technique may be particularly valuable in environmental and food-testing laboratories and for monitoring water quality in the aquaculture industry.  相似文献   
132.
High-frequency stimulation of peripheral nerve bundles is frequently used in clinical tests and physiologic experiments to study presynaptic and postsynaptic effects. To understand the postsynaptic effects, it is important to ensure that each pulse in the train is equally effective in stimulating the presynaptic nerve bundle; however, the optimal interpulse interval (IPI) and the stimulus intensity at which each pulse is equally effective in stimulating the same number of axons are not known. The magnitude of the compound action potential produced by each pulse in a train was tested on the sural nerve of 4 healthy human subjects. The stimulus train (2-4 pulses) was applied to the sural nerve at the lateral malleolus, and neural responses were recorded from just below the knee. With 2-pulse trains, families of curves between IPIs (1-6 ms) and normalized amplitudes of the second response were plotted for different stimulus intensities. Visual inspection of the data showed that the curves fell into 2 groups: with stimulus intensities <2.5x perception threshold (Th), the test response appeared partially at longer IPIs, whereas with stimulus intensities >=3x Th, partial recovery of the test response was earlier. The interval for complete recovery was statistically the same for low- and high-intensity stimulation. With more than 2 pulses in a stimulus train (IPI = 5 ms), the amplitude of the compound action potential (CAP) was not affected significantly. These results are important in understanding both the presynaptic and postsynaptic responses when presynaptic axon bundles are stimulated at high frequencies.  相似文献   
133.
Ethanolic extract (100, 200 and 400 mg/kg, po) of N. jatamansi administered for 14 successive days to Swiss young albino mice (either sex) produced significant antidepressant-like effect in both tail suspension and forced swim tests. The efficacy of the extract was found to be comparable to imipramine (15 mg/kg, po) and sertraline (20 mg/kg, po). Ethanolic extract (200 mg/kg, po) did not show any significant change on locomotor activity of mice as compared to control; hence it did not produce any motor effects. Further, the extract decreased the whole brain MAO-A and MAO-B activities as compared tocontrol, thus increased the levels of monoamines. The antidepressant effect of the extract was also significantly reversed by pretreatment of animals with baclofen (GABAB agonist); when tested in tail suspension test. The results suggested that the antidepressant-like effect of the extract may also be due to interaction with GABAB receptors, resulting in decrease in the levels of GABA in mouse brain. Thus, the extract may have potential therapeutic value for the management of mental depression.  相似文献   
134.

Background  

Lyme disease, caused by Borrelia burgdorferi, affects a large number of people in both the USA and Europe. The mouse is a natural host for this spirochete and is widely used as a model system to study Lyme pathogenesis mechanisms. Since disease manifestations often depend upon the spirochete burden in a particular tissue, it is critical to accurately measure the bacterial number in infected tissues. The current methods either lack sensitivity and specificity (SYBR Green), or require independent analysis of samples in parallel to quantitate host and bacterial DNA (TaqMan). We have developed a novel molecular beacon-based convenient multiplex real-time quantitative PCR assay to identify and detect small numbers of B. burgdorferi in infected mouse tissues.  相似文献   
135.
Our previous studies have identified berberine (BBR), an alkaloid isolated from the Chinese herb huanglian, as a unique cholesterol-lowering drug that upregulates hepatic low density lipoprotein receptor (LDLR) expression through a mechanism of mRNA stabilization. Here, we demonstrate that the root extract of goldenseal, a BBR-containing medicinal plant, is highly effective in upregulation of liver LDLR expression in HepG2 cells and in reducing plasma cholesterol and low density lipoprotein cholesterol (LDL-c) in hyperlipidemic hamsters, with greater activities than the pure compound BBR. By conducting bioassay-driven semipurifications, we demonstrate that the higher potency of goldenseal is achieved through concerted actions of multiple bioactive compounds in addition to BBR. We identify canadine (CND) and two other constituents of goldenseal as new upregulators of LDLR expression. We further show that the activity of BBR on LDLR expression is attenuated by multiple drug resistance-1 (MDR1)-mediated efflux from liver cells, whereas CND is resistant to MDR1. This finding defines a molecular mechanism for the higher activity of CND than BBR. We also provide substantial evidence to show that goldenseal contains natural MDR1 antagonist(s) that accentuate the upregulatory effect of BBR on LDLR mRNA expression. These new findings identify goldenseal as a natural LDL-c-lowering agent, and our studies provide a molecular basis for the mechanisms of action.  相似文献   
136.
137.
BackgroundThere is limited empiric evidence on the coverage of pneumococcal conjugate vaccines (PCVs) required to generate substantial indirect protection. We investigate the association between population PCV coverage and indirect protection against invasive pneumococcal disease (IPD) and pneumonia hospitalisations among undervaccinated Australian children.Methods and findingsBirth and vaccination records, IPD notifications, and hospitalisations were individually linked for children aged <5 years, born between 2001 and 2012 in 2 Australian states (New South Wales and Western Australia; 1.37 million children). Using Poisson regression models, we examined the association between PCV coverage, in small geographical units, and the incidence of (1) 7-valent PCV (PCV7)-type IPD; (2) all-cause pneumonia; and (3) pneumococcal and lobar pneumonia hospitalisation in undervaccinated children. Undervaccinated children received <2 doses of PCV at <12 months of age and no doses at ≥12 months of age. Potential confounding variables were selected for adjustment a priori with the assistance of a directed acyclic graph.There were strong inverse associations between PCV coverage and the incidence of PCV7-type IPD (adjusted incidence rate ratio [aIRR] 0.967, 95% confidence interval [CI] 0.958 to 0.975, p-value < 0.001), and pneumonia hospitalisations (all-cause pneumonia: aIRR 0.991 95% CI 0.990 to 0.994, p-value < 0.001) among undervaccinated children. Subgroup analyses for children <4 months old, urban, rural, and Indigenous populations showed similar trends, although effects were smaller for rural and Indigenous populations. Approximately 50% coverage of PCV7 among children <5 years of age was estimated to prevent up to 72.5% (95% CI 51.6 to 84.4) of PCV7-type IPD among undervaccinated children, while 90% coverage was estimated to prevent 95.2% (95% CI 89.4 to 97.8). The main limitations of this study include the potential for differential loss to follow-up, geographical misclassification of children (based on residential address at birth only), and unmeasured confounders.ConclusionsIn this study, we observed substantial indirect protection at lower levels of PCV coverage than previously described—challenging assumptions that high levels of PCV coverage (i.e., greater than 90%) are required. Understanding the association between PCV coverage and indirect protection is a priority since the control of vaccine-type pneumococcal disease is a prerequisite for reducing the number of PCV doses (from 3 to 2). Reduced dose schedules have the potential to substantially reduce program costs while maintaining vaccine impact.

In an observational study, Jocelyn Chan and colleagues investigate associations between pneumococcal conjugate vaccine coverage and incidence of invasive pneumococcal disease and pneumonia among children under 5 years in Australia.  相似文献   
138.
A laboratory-scale study was conducted to evaluate the feasibility of using palm oil mill effluent (POME) as a major substrate and other nutrients for maximum production of citric acid using the potential fungal strain Aspergillus niger (A103). Statistical optimization of medium composition (substrate–POME, co-substrates–wheat flour and glucose, and nitrogen source–ammonium nitrate) and fermentation time was carried out by central composite design (CCD) to develop a polynomial regression model through the effects of linear, quadratic, and interaction of the factors. The statistical analysis of the results showed that, in the range studied, ammonium nitrate had no significant effect whereas substrate, co-substrates and fermentation time had significant effects on citric acid production. The optimized medium containing 2% (w/w) of substrate concentration (POME), 4% (w/w) of wheat flour concentration, 4% (w/w) of glucose concentration, 0% (w/v) of ammonium nitrate and 5 days fermentation time gave the maximum predicted citric acid of 5.37 g/l which was found to be 1.5 g/l in the experimental run. The determination of coefficient (R 2) from the analysis observed was 0.964, indicating a satisfactory adjustment of the model with the response. The analysis showed that the major substrate POME (P < 0.05), glucose (P < 0.01), nutrient (P < 0.05), and fermentation time (P < 0.01) was more significant for citric acid production. The bioconversion of POME for citric acid production using optimal conditions showed the higher removal of chemical oxygen demand (82%) with the production of citric acid (5.2 g/l) on the final day of fermentation process (7 days). The pH and biosolids accumulation were observed during the bioconversion process.  相似文献   
139.
Stripe rust, caused by Puccinia striiformis West. f.sp. tritici, is one of the most damaging diseases of wheat worldwide. Forty genes for stripe rust resistance have been catalogued so far, but the majority of them are not effective against emerging pathotypes. Triticum monococcum and T. boeoticum have excellent levels of resistance to rusts, but so far, no stripe rust resistance gene has been identified or transferred from these species. A set of 121 RILs generated from a cross involving T. monococcum (acc. pau14087) and T. boeoticum (acc. pau5088) was screened for 3 years against a mixture of pathotypes under field conditions. The parental accessions were susceptible to all the prevalent pathotypes at the seedling stage, but resistant at the adult plant stage. Genetic analysis of the RIL population revealed the presence of two genes for stripe rust resistance, with one gene each being contributed by each of the parental lines. A linkage map with 169 SSR and RFLP loci generated from a set of 93 RILs was used for mapping these resistance genes. Based on phenotypic data for 3 years and the pooled data, two QTLs, one each in T. monococcum acc. pau14087 and T. boeoticum acc. pau5088, were detected for resistance in the RIL population. The QTL in T. monococcum mapped on chromosome 2A in a 3.6 cM interval between Xwmc407 and Xwmc170, whereas the QTL from T. boeoticum mapped on 5A in 8.9 cM interval between Xbarc151 and Xcfd12 and these were designated as QYrtm.pau-2A and QYrtb.pau-5A, respectively. Based on field data for 3 years, their R 2 values were 14 and 24%, respectively. T. monococcum acc. pau14087 and three resistant RILs were crossed to hexaploid wheat cvs WL711 and PBW343, using T. durum as a bridging species with the objective of transferring these genes into hexaploid wheat. The B genome of T. durum suppressed resistance in the F1 plants, but with subsequent backcrossing one resistance gene could be transferred from one of the RILs to the hexaploid wheat background. This gene was derived from T. boeoticum acc. pau5088 as indicated by co-introgression of T. boeoticum sequences linked to stripe rust resistance QTL, QYrtb.pau-5A. Homozygous resistant progenies with 40–42 chromosomes have been identified. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
140.
Substituted 2-amino-7-((6-(4-(2-hydroxyethyl) piperazin-1-yl)-2-methylpyrimidin-4-yl)oxy)-4-phenyl-4H-chromene-3-carbonitriles and 2-amino-7-((6-(4-(2-hydroxyethyl)piperazin-1-yl)-2-methylpyrimidin-4-yl)oxy)-4-phenyl-1,4-dihydroquinoline-3-carbonitriles were synthesized via an efficient multi-component one pot synthesis under mild conditions. These compounds 120 were evaluated against human breast cancer cell lines (MCF-7) and human embryonic kidney cells (HEK293) for cytotoxic activities. Among them, compounds 6, 7, 15, 17 and 19 showed better anti-proliferative activities as (IC50 value 48 ± 1.70, 65 ± 1.13, 92 ± 1.18, 30 ± 1.17 and 16 ± 1.10 µM) than curcumin drug (48 ± 1.11 µM). Molecular docking was also performed with active compounds 6, 7 and 15 against Bcl-2 protein which gave good binding affinity (ΔG = ?9.08, ?8.29 and ?7.70 kcal/mol) respectively. Furthermore, the structure-activity relationship (SAR) analysis revealed that the chromene and quinoline moieties, when attached with pyrimide and piperazine moieties, enhanced anti-proliferative activities.  相似文献   
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