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41.
Hussain R  Ansari A  Talat N  Hasan Z  Dawood G 《PloS one》2011,6(10):e25803
Among the known biomarkers, chemokines, secreted by activated macrophages and T cells, attract groups of immune cells to the site of infection and may determine the clinical outcome. Association studies of CCL-2/MCP-1 -2518 A/G functional SNP linked to high and low phenotypes with tuberculosis disease susceptibility have shown conflicting results in tuberculosis. Some of these differences could be due the variability of latent infection and recent exposure in the control groups. We have therefore carried out a detailed analysis of CCL-2 genotype SNP -2518 (A/G transition) with plasma CCL-2 levels and related these levels to tuberculin skin test positivity in asymptomatic community controls with no known exposure to tuberculosis and in recently exposed household contacts of pulmonary tuberculosis patients. TST positivity was linked to higher concentrations of plasma CCL2 (Mann Whitney U test; p = 0.004) and was more marked when the G allele was present in TST+ asymptomatic controls (A/G; p = 0.01). Recent exposure also had a significant effect on CCL-2 levels and was linked to the G allele (p = 0.007). Therefore association studies for susceptibility or protection from disease should take into consideration the PPD status as well as recent exposure of the controls group used for comparison. Our results also suggest a role for CCL-2 in maintaining the integrity of granuloma in asymptomatic individuals with latent infection in high TB burden settings. Therefore additional studies into the role of CCL-2 in disease reactivation and progression are warranted.  相似文献   
42.
Boswellia papyrifera and Boswellia carterii diffuses smoke polluting air that adversely affects indoor environment that certainly harm human health. Therefore, this study aims at ascertaining the effect of these plants on gonadal hormones and molecular changes in rat spermatozoa. The animals were exposed to 4 g/kg body weight of B. papyrifera and B. carterii daily for 120 days along with suitable controls. Significant decreases in FSH, LH and testosterone levels were evidenced, along with a reduction of protein, sialic acid, and carnitine levels. In sperm physiology, sperm count, motility, speed decrease, whereas sperm anomalies increase. TEM observation indicates morphological changes in plasma and acrosomal membranes, cytoplasmic droplet in the tail region, vacuolated, and disorganization of the mitochondrial sheath. These findings demonstrate that B. papyrifera and B. carterii smoke affects the process of sperm formation and maturation, which indicates the detrimental effects of these plants on the reproductive system.  相似文献   
43.

Background

Poisoning with organophosphorus (OP) insecticides is a major global public health problem, causing an estimated 200,000 deaths each year. Although the World Health Organization recommends use of pralidoxime, this antidote''s effectiveness remains unclear. We aimed to determine whether the addition of pralidoxime chloride to atropine and supportive care offers benefit.

Methods and Findings

We performed a double-blind randomised placebo-controlled trial of pralidoxime chloride (2 g loading dose over 20 min, followed by a constant infusion of 0.5 g/h for up to 7 d) versus saline in patients with organophosphorus insecticide self-poisoning. Mortality was the primary outcome; secondary outcomes included intubation, duration of intubation, and time to death. We measured baseline markers of exposure and pharmacodynamic markers of response to aid interpretation of clinical outcomes. Two hundred thirty-five patients were randomised to receive pralidoxime (121) or saline placebo (114). Pralidoxime produced substantial and moderate red cell acetylcholinesterase reactivation in patients poisoned by diethyl and dimethyl compounds, respectively. Mortality was nonsignificantly higher in patients receiving pralidoxime: 30/121 (24.8%) receiving pralidoxime died, compared with 18/114 (15.8%) receiving placebo (adjusted hazard ratio [HR] 1.69, 95% confidence interval [CI] 0.88–3.26, p = 0.12). Incorporating the baseline amount of acetylcholinesterase already aged and plasma OP concentration into the analysis increased the HR for patients receiving pralidoxime compared to placebo, further decreasing the likelihood that pralidoxime is beneficial. The need for intubation was similar in both groups (pralidoxime 26/121 [21.5%], placebo 24/114 [21.1%], adjusted HR 1.27 [95% CI 0.71–2.29]). To reduce confounding due to ingestion of different insecticides, we further analysed patients with confirmed chlorpyrifos or dimethoate poisoning alone, finding no evidence of benefit.

Conclusions

Despite clear reactivation of red cell acetylcholinesterase in diethyl organophosphorus pesticide poisoned patients, we found no evidence that this regimen improves survival or reduces need for intubation in patients with organophosphorus insecticide poisoning. The reason for this failure to benefit patients was not apparent. Further studies of different dose regimens or different oximes are required.

Trial Registration

Controlled-trials.com ISRCTN55264358 Please see later in the article for Editors'' Summary  相似文献   
44.
Populations in upstream versus downstream river locations can be exposed to vastly different environmental and ecological conditions and can thus harbor different genetic resources due to selection and neutral processes. An interesting question is how upstream–downstream directionality in rivers affects the evolution of immune response genes. We used next‐generation amplicon sequencing to identify eight alleles of the major histocompatibility complex (MHC) class II β exon 2 in the cyprinid longnose dace (Rhinichthys cataractae) from three rivers in Alberta, upstream and downstream of municipal and agricultural areas along contaminant gradients. We used these data to test for directional and balancing selection on the MHC. We also genotyped microsatellite loci to examine neutral population processes in this system. We found evidence for balancing selection on the MHC in the form of increased nonsynonymous variation relative to neutral expectations, and selection occurred at more amino acid residues upstream than downstream in two rivers. We found this pattern despite no population structure or isolation by distance, based on microsatellite data, at these sites. Overall, our results suggest that MHC evolution is driven by upstream–downstream directionality in fish inhabiting this system.  相似文献   
45.
Arabidopsis thaliana has eight genes encoding members of the type 1B heavy metal–transporting subfamily of the P-type ATPases. Three of these transporters, HMA2, HMA3, and HMA4, are closely related to each other and are most similar in sequence to the divalent heavy metal cation transporters of prokaryotes. To determine the function of these transporters in metal homeostasis, we have identified and characterized mutants affected in each. Whereas the individual mutants exhibited no apparent phenotype, hma2 hma4 double mutants had a nutritional deficiency phenotype that could be compensated for by increasing the level of Zn, but not Cu or Co, in the growth medium. Levels of Zn, but not other essential elements, in the shoot tissues of a hma2 hma4 double mutant and, to a lesser extent, of a hma4 single mutant were decreased compared with the wild type. Together, these observations indicate a primary role for HMA2 and HMA4 in essential Zn homeostasis. HMA2promoter- and HMA4promoter-reporter gene constructs provide evidence that HMA2 and HMA4 expression is predominantly in the vascular tissues of roots, stems, and leaves. In addition, expression of the genes in developing anthers was confirmed by RT-PCR and was consistent with a male-sterile phenotype in the double mutant. HMA2 appears to be localized to the plasma membrane, as indicated by protein gel blot analysis of membrane fractions using isoform-specific antibodies and by the visualization of an HMA2-green fluorescent protein fusion by confocal microscopy. These observations are consistent with a role for HMA2 and HMA4 in Zn translocation. hma2 and hma4 mutations both conferred increased sensitivity to Cd in a phytochelatin-deficient mutant background, suggesting that they may also influence Cd detoxification.  相似文献   
46.
Here we quantitatively characterize two common homogenization strategies in the analysis of tissue proteomes: classical manual homogenization (MH) and an automated frozen disruption (AFD) technique. In a variety of tissues, many proteins were more efficiently extracted, resolved and detected, with high reproducibility after AFD, amounting to as much as 2% of the total resolved proteome. The benefits of AFD over MH are 2-fold: (1) AFD yields a much more thorough homogenate than MH; and (2) as a deep frozen alternative, AFD maintains a level of biological complexity that is not retained during MH. Thus, AFD coupled with refined 2DE protocols and Sypro Ruby staining yields quantitative proteomic analyses.  相似文献   
47.
Deleted forms of ricin B chain (RTB) containing only one of the two galactose binding sites were produced inE. coli and targeted to the periplasm by fusion to theompA orompF signal sequences. The proteins were then isolated from the periplasm and their sugar binding properties assessed. Previous studies investigating the properties of such proteins produced inXenopus laevis oocytes suggested that deleted forms of RTB, when not glycosylated, retain their ability to bind simple sugars, unlike the full-length unglycosylated proteins. When produced inE. coli however we found that only one, EB733, of a number of deleted forms of RTB closely related to those previously produced inXenopus laevis oocytes, bound to simple sugars. All of the deletion forms of RTB were found to bind in the asialofetuin binding assay; an assay which has been previously utilized to measure binding of lectins to the terminal galactose residues of glycoprotein oligosaccharides. However, in contrast to glycosylated RTB, binding of the deletion mutants could be competed to only a small degree or not at all with galactose. The only deletion mutant observed to bind to free galactose when produced inE. coli corresponded closely to the complete domain 2 of RTB. It is assumed that this mutant forms a stable structure similar to that of the C-terminal domain in the full-length protein. The structural integrity of EB733 was not only suggested by its sugar binding properties and solubility but also by its consistently higher level of expression and the absence of any apparent susceptibility toE. coli proteases.Abbreviations RTA ricin toxin A chain - RTB ricin toxin B chain - ER endoplasmic reticulum - SDS-PAGE sodium dodecyl sulphate-polyacrylamide gel electrophoresis - IPTG isopropyl -d-thiogalactopyranoside  相似文献   
48.
A study was performed to assess the preference of fourteen mango cultivars for fruit flies and their management by bagging. So the choice of Tephritid flies to mango cultivars during fruiting phase is crucial. Fourteen different cultivars of mango viz., ‘Dusehri’, ‘Malda’, ‘Langra’ early cultivars, ‘Chaunsa’, ‘Fajri Klan’, ‘Sensation’ medium whereas ‘Sanglakhi’, ‘Retaul-12’, ‘Mehmood Khan’, ‘Tukhmi’, ‘Kala Chaunsa’, ‘Chitta Chaunsa’, ‘Dai Wala’ and ‘Sobey De Ting’ late cultivars were assessed for their suitability for fruit flies. The results indicate that the population density of fruit flies was higher on late cultivars like ‘Sanglakhi’ (20.61 percent), ‘Mehmood Khan’ (20.22 percent) and ‘Reutal-12’ (19.92 percent) were proved to be highly susceptible to fruit flies. Among these the cultivar ‘Reutal-12’ was selected being commercial and future cultivar for the management of fruit flies through bagging. The results reported that the attack of tephritid fruit flies and other insect pests were zero in bagged fruits as compared with control. It was further recorded that the bagged fruits has maximum average fruit weight i.e. 203.50 and 197.83 g per fruit was noted in those treatments where butter paper bag and brown paper bag was wrapped with better coloration as compared with un-bagged fruit with 159.5 g per fruit. Similarly, on an average fruit length were more i.e. 90.17, 91.33 mm in bagged fruit and 85.33 in un-bagged fruits. Furthermore, bagged fruits have zero incidence of disease with reduced fruit crack, fruit sunburn, mechanical damage, bird damage, fruit blemished and agrochemical residues on the fruit. So, it is concluded that the special attention should be given on ‘Reutal-12’ for the management of fruit flies when devising an IPM program for the control of fruit flies. Further, bagging has proved to be the good agricultural practices for the production of quality mango.  相似文献   
49.
50.
Cell–cell and cell–matrix adhesions are fundamental to numerous physiological processes, including angiogenesis, tumourigenesis, metastatic spreading and wound healing. We use cellular potts model to computationally predict the organisation of cells within a 3D matrix. The energy potentials regulating cell–cell (JCC) and cell–matrix (JMC) adhesive interactions are systematically varied to represent different, biologically relevant adhesive conditions. Chemotactically induced cell migration is also addressed. Starting from a cluster of cells, variations in relative cell adhesion alone lead to different cellular patterns such as spreading of metastatic tumours and angiogenesis. The combination of low cell–cell adhesion (high JCC) and high heterotypic adhesion (low JMC) favours the fragmentation of the original cluster into multiple, smaller cell clusters (metastasis). Conversely, cellular systems exhibiting high-homotypic affinity (low JCC) preserve their original configuration, avoiding fragmentation (organogenesis). For intermediate values of JCC and JMC (i.e. JCC/JMC ~ 1), tubular and corrugated structures form. Fully developed vascular trees are assembled only in systems in which contact-inhibited chemotaxis is activated upon cell contact. Also, the rate of secretion, diffusion and sequestration of chemotactic factors, cell deformability and motility do not significantly affect these trends. Further developments of this computational model will predict the efficacy of therapeutic interventions to modulate the diseased microenvironment by directly altering cell cohesion.  相似文献   
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