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51.
Soil-transmitted helminthiasis (STH) is a scourge to the health and well-being of infants and pre-schoolchildren throughout many parts of sub-Saharan Africa. To improve maternal and child health, regular de-worming is recommended and often delivered from mother and child health (MCH) clinics, yet there have been few studies monitoring the progress and impact of interventions on local levels of disease. A cross-sectional parasitological survey, supplemented with questionnaires, was therefore conducted across 10 Ungujan villages examining mothers (n=322) and their pre-school children (n=359). Within children, mean prevalence of ascariasis, trichuriasis and hookworm was 8.6% (95% CI 5.5-11.8), 18.9% (95% CI 14.5-23.4) and 1.7% (95% CI 0.2-3.5) while in mothers mean prevalence was 6.7% (95% CI 3.7-9.7), 11.9% (95% CI 8.0-15.8) and 1.9% (95% CI 0.2-3.5), respectively. There was, however, significant spatial heterogeneity of STH by village, 2 villages having much elevated levels of infection, although general access to anthelminthics and utilization of village MCH clinics was good. Levels of parasite aggregation (k) were determined and a multilevel logistic regression model identified access to a household latrine [OR=0.56 (95% CI 0.32-0.99)] and having an infected household member [OR=3.72 (95% CI 2.22-6.26)] as observed risk factors. To further investigate worm burdens of Ascaris lumbricoides, adult worms were expelled using Combantrin and measured. A negative relationship between mean worm burden and mean worm mass was found. Villages in the north of Unguja represent locations where there is elevated prevalence of both ascariasis and trichuriasis and it appears that local factors are particularly favourable for transmission of these helminths. From a perspective of control, in such locations, intervention efforts should be stepped up and greater efforts placed upon improving household sanitation.  相似文献   
52.
The protein glycation inhibitory activity of ethanolic extract of Lawsonia inermis (henna) plant tissues was evaluated in vitro using the model system of bovine serum albumin and glucose. Protein oxidation and glycation are posttranslational modifications that are implicated in the pathological development of many age-related disease processes. This study investigated the effects of Lawsonia inermis ethanolic extract and its components, on protein damage induced by a free radical generator in in vitro assay system. We found that alcoholic extract of Lawsonia inermis can effectively protect against protein damage and showed that its action is mainly due to Lawsone. In addition, the presence of gallic acid also plays an important role in the protective activity against protein oxidation and glycation. Two known compounds, namely, Lawsone and gallic acid previously isolated from this plant were subjected to glycation bioassay for the first time. It was found that the alcoholic extract, lawsone (1) and gallic acid (2) showed significant inhibition of Advanced Glycated End Products (AGEs) formation and exhibit 77.95%, 79.10% and 66.98% inhibition at a concentration of 1500 microg/mL, 1000 microg/mL and 1000 microM respectively. Lawsonia inermis, compounds 1 and 2 were found to be glycation inhibitors with IC(50) 82.06 +/- 0.13 microg/mL, 67.42 +/- 1.46 microM and 401.7 +/- 6. 23 microM respectively. This is the first report on the glycation activity of these compounds and alcoholic extract of Lawsonia inermis.  相似文献   
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Epithelial ovarian cancer is a highly heterogeneous disease and remains the most lethal gynaecological malignancy in the Western world. Therapeutic approaches need to account for inter-patient and intra-tumoural heterogeneity and detailed characterization of in vitro models representing the different histological and molecular ovarian cancer subtypes is critical to enable reliable preclinical testing. There are approximately 100 publicly available ovarian cancer cell lines but their cellular and molecular characteristics are largely undescribed. We have characterized 39 ovarian cancer cell lines under uniform conditions for growth characteristics, mRNA/microRNA expression, exon sequencing, drug response for clinically-relevant therapeutics and collated all available information on the original clinical features and site of origin. We tested for statistical associations between the cellular and molecular features of the lines and clinical features. Of the 39 ovarian cancer cell lines, 14 were assigned as high-grade serous, four serous-type, one low-grade serous and 20 non-serous type. Three morphological subtypes: Epithelial (n = 21), Round (n = 7) and Spindle (n = 12) were identified that showed distinct biological and molecular characteristics, including overexpression of cell movement and migration-associated genes in the Spindle subtype. Comparison with the original clinical data showed association of the spindle-like tumours with metastasis, advanced stage, suboptimal debulking and poor prognosis. In addition, the expression profiles of Spindle, Round and Epithelial morphologies clustered with the previously described C1-stromal, C5-mesenchymal and C4 ovarian subtype expression profiles respectively. Comprehensive profiling of 39 ovarian cancer cell lines under controlled, uniform conditions demonstrates clinically relevant cellular and genomic characteristics. This data provides a rational basis for selecting models to develop specific treatment approaches for histological and molecular subtypes of ovarian cancer.  相似文献   
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56.
The present study was set to identify the members of An. maculipennis complex, which includes effective malaria vectors, throughout the Mediterranean region of Turkey using the second internal transcribed spacer of ribosomal DNA (rDNA-ITS2) sequences from 200 specimens. Resulting sequences of this complex from the Mediterranean region revealed the presence of three species belonging to the An. maculipennis complex, namely An. sacharovi, An. maculipennis s.s. and An. melanoon. The lengths of ITS2 region were 284, 294 and 306 bp in length for An. maculipennis s.s., An. melanoon and An. sacharovi respectively. While no sequence divergence was observed within any species, An. sacharovi was the most distantly related species from An. maculipennis s.s. and An. melanoon with a sequence divergence of 15.1% and 15.4%, respectively. While An. melanoon was the rare species, An. maculipennis s.s., was the most abundant and An. sacharovi was the most wide spread one.  相似文献   
57.
A proteomic study was conducted to investigate physiological factors affecting feeding behaviour by larvae of the insect, Plutella xylostella, on herbivore-susceptible and herbivore-resistant Arabidopsis thaliana. The leaves of 162 recombinant inbred lines (Rils) were screened to detect genotypes upon which Plutella larvae fed least (P. xylostella-resistant) or most (P. xylostella-susceptible). 2D-PAGE revealed significant differences in the proteomes between the identified resistant and susceptible Rils. The proteomic results, together with detection of increased production of hydrogen peroxide in resistant Rils, suggest a correlation between P. xylostella resistance and the production of increased levels of reactive oxygen species (ROS), in particular H2O2, and that this was expressed prior to herbivory. Many of the proteins that were more abundant in the Plutella-resistant Rils are known in other biological systems to be involved in limiting ROS damage. Such proteins included carbonic anhydrases, malate dehydrogenases, glutathione S-transferases, isocitrate dehydrogenase-like protein (R1), and lipoamide dehydrogenase. In addition, patterns of germin-like protein 3 isoforms could also be indicative of higher levels of reactive oxygen species in the resistant Rils. Consistent with the occurrence of greater oxidative stress in the resistant Rils is the observation of greater abundance in susceptible Rils of polypeptides of the photosynthetic oxygen-evolving complex, which are known to be damaged under oxidative stress. The combined results suggest that enhanced production of ROS may be a major pre-existing mechanism of Plutella resistance in Arabidopsis, but definitive corroboration of this requires much further work.  相似文献   
58.
The present study was conducted to characterize the newly invasive papaya mealybug Paracoccus marginatus Williams and Granara de Willink in Kenya using molecular techniques and to establish the potential risk of spread of the pest. Although abundant literature of P. marginatus outbreaks exists in other parts of the world, studies from Africa are rare. Our results revealed significant similarity between Kenyan samples with GenBank accession number KP692333.1 of P. marginatus. Phylogenetic analyses generated a tree that was paraphyletic with two clusters showing low genetic distance values for the P. marginatus sequences, which diverged from that of Planococcus citri. Our models displayed an optimal performance with mean area under the curve value of 0.82 and 0.98 for Genetic Algorithm for Rule-Set Production (GARP) and maximum entropy modelling (MaxEnt), respectively. Isothermality was the most influential variable in determining the potential distribution of P. marginatus with a 69% contribution to the models. Other variables included temperature mean diurnal range temperature seasonality, temperature annual range and annual precipitation in decreasing order of contribution. Current prediction by both models exceeded the existing range of P. marginatus, exacerbating the potential threat of the pest. GARP was more conservative in predicting suitable areas for P. marginatus, while MaxEnt showed further expansion by the year 2050. Our findings provide important information to guide biosecurity agencies in decision-making to prevent the spread and enhance control efforts of P. marginatus.  相似文献   
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Cerebral ischemia (CI), caused by the deprivation of oxygen and glucose to the brain, is the leading cause of permanent disability. Neuronal demise in CI has been linked to several pathways which include cyclooxygenases (COX) − mediated production of prostaglandins (PGs) and subsequently reactive oxygen species (ROS), aquaporin-4 (AQ-4) − mediated brain edema and acidsensing ion channel-1a (ASIC-1a) − mediated acidotoxicity, matrix remodeling, in addition to others. Several non-steroidal antiinflammatory drugs (NSAIDs) are presently in use to prevent these pathways. However, owing to the large number of processes involved, there is high drug load. So, identifying drugs with multimodal role has always been a frequently sought venture. The present in silico study has been performed to find out the relative efficacy of three different NSAIDs (Piroxicam, Aspirin and Nimesulide) in preventing neurodegeneration in CI, with respect to their inhibitory potential on COXs, AQ-4 and ASIC-1a. We find that piroxicam is the most potent inhibitor of these receptors as compared to the NSAIDs under investigation. Since piroxicam has already been reported to inhibit N-methyl-D-aspartate (NMDA) receptor and matrix metalloproteinases (MMPs), which are also linked to CI-induced neurodegeneration, we hereby propose piroxicam to be a gold-standard drug in preventing neurodegeneration in CI.  相似文献   
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