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131.
We determined the effects of past and future climate changes on the distribution of the Montivipera raddei species complex (MRC) that contains rare and endangered viper species limited to Iran, Turkey and Armenia. We also investigated the current distribution of MRC to locate unidentified isolated populations as well as to evaluate the effectiveness of the current network of protected areas for their conservation. Present distribution of MRC was modeled based on ecological variables and model performance was evaluated by field visits. Some individuals at the newly identified populations showed uncommon morphological characteristics. The distribution map of MRC derived through modeling was then compared with the distribution of protected areas in the region. We estimated the effectiveness of the current protected area network to be 10%, which would be sufficient for conserving this group of species, provided adequate management policies and practices are employed. We further modeled the distribution of MRC in the past (21,000 years ago) and under two scenarios in the future (to 2070). These models indicated that climatic changes probably have been responsible for an upward shift in suitable habitats of MRC since the Last Glacial Maximum, leading to isolation of allopatric populations. Distribution will probably become much more restricted in the future as a result of the current rate of global warming. We conclude that climate change most likely played a major role in determining the distribution pattern of MRC, restricting allopatric populations to mountaintops due to habitat alterations. This long-term isolation has facilitated unique local adaptations among MRC populations, which requires further investigation. The suitable habitat patches identified through modeling constitute optimized solutions for inclusion in the network of protected areas in the region.  相似文献   
132.
Caspase 8 (CASP8) gene plays a key role in the regulation of apoptotic cell death. Expression variation in this gene has been associated with the risk of breast cancer. The aim of this study was to investigate the association of rs3834129 and rs3769821, as functional variants, and their haplotypes with molecular profile as well as the risk of breast cancer in an Iranian population. A case-control study was conducted on 812 participants including 293 breast cancer patients and 519 healthy controls. Genotyping was performed by polymerase chain reaction–based methods. Statistical analysis was performed using SPSS Ver16. The association between polymorphisms and haplotypes with the risk of breast cancer was estimated by calculating odds ratios (OR) and chi-square (χ2) tests. In comparison with ins allele (I) of rs3834129, carriers of del allele (D) showed a lower risk of breast cancer (OR, 0.65; 95% confidence interval [CI], 0.49-0.87; P = 0.004). The multivariate logistic regression model indicated DD genotype as an independent factor for a decreased risk of breast cancer in our population (OR, 0.18; 95% CI, 0.06-0.58; P = 0.004). Also, the C allele of rs3769821 was associated with a 43% increased risk of breast cancer (P = 0.005); however, after adjustment for confounding factors, no association with rs3769821 and breast cancer was observed. In addition, D-T haplotype and diplotype presented protective effects (P < 0.05). Our results indicate that genetic variations in the promoter region of CASP8 gene, especially rs3834129, may serve as a genetic risk factor for breast cancer in an Iranian population.  相似文献   
133.

Background

Appropriate health and nutrition interventions to prevent long-term adverse effects in children are necessary before two years of age. One such intervention may include population-based deworming, recommended as of 12 months of age by the World Health Organization in soil-transmitted helminth (STH)-endemic areas; however, the benefit of deworming has been understudied in early preschool-age children.

Methodology/Principal Findings

A randomized, double-blind, placebo-controlled trial was conducted to determine the effect of deworming (500 mg single-dose crushed mebendazole tablet) on growth in one-year-old children in Iquitos, Peru. Children were enrolled during their routine 12-month growth and development clinic visit and followed up at their 18 and 24-month visits. Children were randomly allocated to: Group 1: deworming at 12 months and placebo at 18 months; Group 2: placebo at 12 months and deworming at 18 months; Group 3: deworming at both 12 and 18 months; or Group 4: placebo at both 12 and 18 months (i.e. control group). The primary outcome was weight gain at the 24-month visit. An intention-to-treat approach was used. A total of 1760 children were enrolled between September 2011 and June 2012. Follow-up of 1563 children (88.8%) was completed by July 2013. STH infection was of low prevalence and predominantly light intensity in the study population. All groups gained between 1.93 and 2.05 kg on average over 12 months; the average difference in weight gain (kg) compared to placebo was: 0.05 (95% CI: -0.05, 0.17) in Group 1; -0.07 (95%CI: -0.17, 0.04) in Group 2; and 0.04 (95%CI: -0.06, 0.14) in Group 3. There was no statistically significant difference in weight gain in any of the deworming intervention groups compared to the control group.

Conclusions

Overall, with one year of follow-up, no effect of deworming on growth could be detected in this population of preschool-age children. Low baseline STH prevalence and intensity and/or access to deworming drugs outside of the trial may have diluted the potential effect of the intervention. Additional research is required to overcome these challenges and to contribute to strengthening the evidence base on deworming.

Trial Registration

ClinicalTrials.gov (NCT01314937)  相似文献   
134.
Annona muricata has been used in folk medicine for the treatment of cancer and tumors. This study evaluated the chemopreventive properties of an ethyl acetate extract of A. muricata leaves (EEAML) on azoxymethane-induced colonic aberrant crypt foci (ACF) in rats. Moreover, the cytotoxic compound of EEAML (Annomuricin E) was isolated, and its apoptosis-inducing effect was investigated against HT-29 colon cancer cell line using a bioassay-guided approach. This experiment was performed on five groups of rats: negative control, cancer control, EEAML (250 mg/kg), EEAML (500 mg/kg) and positive control (5-fluorouracil). Methylene blue staining of colorectal specimens showed that application of EEAML at both doses significantly reduced the colonic ACF formation compared with the cancer control group. Immunohistochemistry analysis showed the down-regulation of PCNA and Bcl-2 proteins and the up-regulation of Bax protein after administration of EEAML compared with the cancer control group. In addition, an increase in the levels of enzymatic antioxidants and a decrease in the malondialdehyde level of the colon tissue homogenates were observed, suggesting the suppression of lipid peroxidation. Annomuricin E inhibited the growth of HT-29 cells with an IC50 value of 1.62 ± 0.24 μg/ml after 48 h. The cytotoxic effect of annomuricin E was further substantiated by G1 cell cycle arrest and early apoptosis induction in HT-29 cells. Annomuricin E triggered mitochondria-initiated events, including the dissipation of the mitochondrial membrane potential and the leakage of cytochrome c from the mitochondria. Prior to these events, annomuricin E activated caspase 3/7 and caspase 9. Upstream, annomuricin E induced a time-dependent upregulation of Bax and downregulation of Bcl-2 at the mRNA and protein levels. In conclusion, these findings substantiate the usage of A. muricata leaves in ethnomedicine against cancer and highlight annomuricin E as one of the contributing compounds in the anticancer activity of A. muricata leaves.  相似文献   
135.
Glycerol is the main compatible solute in yeast Saccharomyces cerevisiae. When faced with osmotic stress, for example during semi-solid state bread dough fermentation, yeast cells produce and accumulate glycerol in order to prevent dehydration by balancing the intracellular osmolarity with that of the environment. However, increased glycerol production also results in decreased CO2 production, which may reduce dough leavening. We investigated the effect of yeast glycerol production level on bread dough fermentation capacity of a commercial bakery strain and a laboratory strain. We find that Δgpd1 mutants that show decreased glycerol production show impaired dough fermentation. In contrast, overexpression of GPD1 in the laboratory strain results in increased fermentation rates in high-sugar dough and improved gas retention in the fermenting bread dough. Together, our results reveal the crucial role of glycerol production level by fermenting yeast cells in dough fermentation efficiency as well as gas retention in dough, thereby opening up new routes for the selection of improved commercial bakery yeasts.  相似文献   
136.
The biological traits of the entomopathogenic nematodes (EPNs), Steinernema carpocapsae and Heterorhabditis bacteriophora, against the larvae of the leopard moth, Zeuzera pyrina were evaluated in the laboratory. The traits included pathogenicity, penetration potential as well as foraging behaviour. Plate assays were performed using a range of EPN concentrations (5, 10, 20, 50 and 100 infective juveniles (IJs) per larva). The LC50 values for S. carpocapsae and H. bacteriophora were 6.4 and 8.4 IJs larva?1 after 72 h. Both EPN species caused high mortality in branch experiments. Significantly higher mortality rates occurred in the larger larvae after exposure to S. carpocapsae. Both EPN species successfully penetrated the Z. pyrina larvae as well as larvae of Galleria mellonella L. (Lepidoptera: Galleridae).The proportional response of H. bacteriophora to host-associated cues was strongly higher than S. carpocapsae in Petri dishes containing agar 1, 12 and 24 h after EPN application. These results highlight the efficiency of EPNs for the control of Z. pyrina larvae. However, due to the cryptic habitat of Z. pyrina larvae in their galleries in the trees, field trails need to be conducted to further evaluate this potential.  相似文献   
137.
A new species of Alternaria causing leaf spot of pepper (Capsicum annuum) obtained from the Cameron highlands, Pahang, Malaysia, was determined based on phylogenetic analyses, morphological characteristics, and pathogenicity assays. Phylogenetic analyses of combined dataset of the glyceraldehyde-3-phosphate dehydrogenase (gpd), Alternaria allergen a 1 (Alt a1) and calmodulin genes revealed that the new isolates clustered into a subclade distinct from the closely related Alternaria species A. tomato and A. burnsii. The solitary or short chains of conidia resemble those of A. burnsii. However, conidia with long beaks are morphologically similar to A. tomato. Hence, the pathogenic fungus is proposed as Alternaria capsicicola sp. nov. Pathogenicity assays indicated that A. capsicicola causes leaf spot on pepper.  相似文献   
138.
139.
CircRNAs are a superabundant and highly conserved group of noncoding RNAs (ncRNAs) that are characterized by their high stability and integrity compared with linear forms of ncRNAs. Recently, their critical role in gene expression regulation has been shown; thus, it is not far‐fetched to believe that their abnormal expression can be a cause of different kinds of diseases such as cancer, neurodegenerative, and autoimmune diseases. They can have a function in variety of biological processes such as microRNA (miRNA) sponging, interacting with RNA‐binding proteins, or even an ability to translate to proteins. A huge challenge in finding diagnostic biomarkers is finding noninvasive biomarkers that can be detected in human fluids, especially blood samples. CircRNAs are becoming candidate biomarkers for diagnosis and prognosis of these diseases through their ability to transverse from the blood‐brain barrier and their broad presence in circulating exosomes. The circRNA for miRNA‐7 (ciRS‐7) is newly recognized, and acknowledged to being related to human pathology and cancer progression. In this review, we first briefly summarize the latest studies about their characteristics, biogenesis, and their mechanisms of action in the regulation and development of human diseases. Finally, we provide a list of diseases that are linked to one member of this novel class of ncRNAs called ciRS‐7.  相似文献   
140.
International Journal of Peptide Research and Therapeutics - Breast cancer is the most common cancer in women, worldwide. The correlation between breast cancer malignancy and human epidermal growth...  相似文献   
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