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1.
Molecular Biology Reports - This work aims to evaluate the renoprotective effect of luteolin on expression of Nrf2 and miR320 in ischemia–reperfusion (I/R) injury in rats. Thirty rats were...  相似文献   
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IntroductionCutaneous leishmaniasis (CL) is currently a health problem in several parts of Iran, particularly Kerman. This study was conducted to determine the incidence and trend of CL in Kerman during 2014–2020 and its forecast up to 2023. The effects of meteorological variables on incidence was also evaluated.Materials and methods4993 definite cases of CL recorded from January 2014 to December 2020 by the Vice-Chancellor for Health at Kerman University of Medical Sciences were entered. Meteorological variables were obtained from the national meteorological site. The time series SARIMA methods were used to evaluate the effects of meteorological variables on CL.ResultsMonthly rainfall at the lag 0 (β = -0.507, 95% confidence interval:-0.955,-0.058) and monthly sunny hours at the lag 0 (β = -0.214, 95% confidence interval:-0.308,-0.119) negatively associated with the incidence of CL. Based on the Akaike information criterion (AIC) the multivariable model (AIC = 613) was more suitable than univariable model (AIC = 690.66) to estimate the trend and forecast the incidence up to 36 months.ConclusionThe decreasing pattern of CL in Kerman province highlights the success of preventive, diagnostic and therapeutic interventions during the recent years. However, due to endemicity of disease, extension and continuation of such interventions especially before and during the time periods with higher incidence is essential.  相似文献   
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Social learning offers an efficient route through which humans and other animals learn about potential dangers in the environment. Such learning inherently relies on the transmission of social information and should imply selectivity in what to learn from whom. Here, we conducted two observational learning experiments to assess how humans learn about danger and safety from members (‘demonstrators'') of an other social group than their own. We show that both fear and safety learning from a racial in-group demonstrator was more potent than learning from a racial out-group demonstrator.  相似文献   
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The development of meiotic division and associated genetic recombination paved the way for evolutionary changes. However, the secondary and tertiary structure and functional domains of many of the proteins involved in genetic recombination have not been studied in detail. We used the human Dmc1 gene product along with secondary and tertiary domain structures of Escherichia coli RecA protein to help determine the molecular structure and function of maize Dmc1, which is required for synaptonemal complex formation and cell cycle progression. The maize recombinase Dmc1 gene was cloned and characterized, using rice Dmc1 cDNA as an orthologue. The deduced amino acid sequence was used for elaborating its 3-D structure, and functional analysis was made with the CDD software, showing significant identity of the Dmc1 gene product in Zea mays with that of Homo sapiens. Based on these results, the domains and motives of WalkerA and WalkerB as ATP binding sites, a multimer site (BRC) interface, the putative ssDNA binding L1 and L2 loops, the putative dsDNA binding helix-hairpin-helix, a polymerization motif, the subunit rotation motif, and a small N-terminal domain were proposed for maize recombinase Dmc1.  相似文献   
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Purple acid phosphatases are metal-containing hydrolases. While their precise biological role(s) is unknown, the mammalian enzyme has been linked in a variety of biological circumstances (e.g., osteoporosis) with increased bone resorption. Inhibition of the human enzyme is a possible strategy for the treatment of bone-resorptive diseases such as osteoporosis. Previously, we determined the crystal structure of pig purple acid phosphatase to 1.55A and we showed that it is a good model for the human enzyme. Here, a study of the pH dependence of its kinetic parameters showed that the pig enzyme is most efficient at pH values similar to those encountered in the osteoclast resorptive space. Based on the observation that phosphotyrosine-containing peptides are good substrates for pig purple acid phosphatase, peptides containing a range of phosphotyrosine mimetics were synthesized. Kinetic analysis showed that they act as potent inhibitors of mammalian and plant purple acid phosphatases, with the best inhibitors exhibiting low micromolar inhibition constants at pH 3-5. These compounds are thus the most potent organic inhibitors yet reported for the purple acid phosphatases.  相似文献   
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Background

Telomeres are the protective arrays of tandem TTAGGG sequence and associated proteins at the termini of chromosomes. Telomeres shorten at each cell division due to the end-replication problem and are maintained above a critical threshold in malignant cancer cells to prevent cellular senescence or apoptosis. With the recent advances in massive parallel sequencing, assessing telomere content in the context of other cancer genomic aberrations becomes an attractive possibility. We present the first comprehensive analysis of telomeric DNA content change in tumors using whole-genome sequencing data from 235 pediatric cancers.

Results

To measure telomeric DNA content, we counted telomeric reads containing TTAGGGx4 or CCCTAAx4 and normalized to the average genomic coverage. Changes in telomeric DNA content in tumor genomes were clustered using a Bayesian Information Criterion to determine loss, no change, or gain. Using this approach, we found that the pattern of telomeric DNA alteration varies dramatically across the landscape of pediatric malignancies: telomere gain was found in 32% of solid tumors, 4% of brain tumors and 0% of hematopoietic malignancies. The results were validated by three independent experimental approaches and reveal significant association of telomere gain with the frequency of somatic sequence mutations and structural variations.

Conclusions

Telomere DNA content measurement using whole-genome sequencing data is a reliable approach that can generate useful insights into the landscape of the cancer genome. Measuring the change in telomeric DNA during malignant progression is likely to be a useful metric when considering telomeres in the context of the whole genome.  相似文献   
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Transposable elements (TEs) are major sources of genetic variation, and mating systems are believed to play a significant role in their dynamics. For example, insertion number is expected to be higher in sexual than in asexual organisms due to the inability of TEs to colonize new genomes in the absence of sex. The goal of this study was to determine the impact of the loss of sexual reproduction on TE load. Daphnia pulex has two reproductive modes, obligate and cyclical parthenogenesis, which differ with respect to the production of diapausing eggs. Cyclical parthenogens produce them meiotically, while obligate parthenogens produce them clonally. Pokey is a TTAA-specific DNA transposon, and is a stable component of Daphnia genomes. We used a PCR-based approach, TE-Display, to estimate the number of Pokey insertions in 22 cyclic and 22 obligate isolates of D. pulex. As expected, the copy number of Pokey insertions is significantly higher in cyclic than in obligate isolates. However, the distribution of elements among isolates within each breeding system is similar, which is congruent with the recent establishment of obligate lineages from a cyclic ancestor. We also assayed 46 isolates from eight cyclic populations and found that very few Pokey insertions were observed in more than one isolate, suggesting that Pokey has been active recently. Sequencing of PCR products from the TE-Display analysis shows that Pokey inserts into both coding and noncoding regions of the genome. However, there is no obvious similarity among sequences downstream of the TTAA Pokey insertion site.  相似文献   
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The lateral prefrontal and orbitofrontal cortices have both been implicated in emotion regulation, but their distinct roles in regulation of negative emotion remain poorly understood. To address this issue we enrolled 58 participants in an fMRI study in which participants were instructed to reappraise both negative and neutral stimuli. This design allowed us to separately study activations reflecting cognitive processes associated with reappraisal in general and activations specifically related to reappraisal of negative emotion. Our results confirmed that both the dorsolateral prefrontal cortex (DLPFC) and the lateral orbitofrontal cortex (OFC) contribute to emotion regulation through reappraisal. However, activity in the DLPFC was related to reappraisal independently of whether negative or neutral stimuli were reappraised, whereas the lateral OFC was uniquely related to reappraisal of negative stimuli. We suggest that relative to the lateral OFC, the DLPFC serves a more general role in emotion regulation, perhaps by reflecting the cognitive demand that is inherent to the regulation task.  相似文献   
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Dericorys albidula Serville (Orthoptera: Dericorythidae) is a major pest of Haloxylon ammodendron and other saxaul plant species in the Qom province, Iran. Using fungal insecticides can be an alternative method for chemical insecticides. Effect of insecticide fungi, Metarhizium anisopliae var. acridum, on the various nymphs of D. albidula was studied in the field through 2005 and 2006. Fixed concentrations of fungi (106, 107, 108, 109, 1010 and 1013 spore mL?1) were prepared as gasoline formulation and were sprayed on the locusts on H. ammodendron trees, and mortality percentage was recorded 15 days after treatment. The results showed that various concentrations significantly affected on the second, third, fourth and fifth nymphal instars of D. albidula compared to control in 2006, although this effect was lower in 2005 on nymphs. Mortality of the highest concentration (1013 spore mL?1) was higher (17.6–24%) than other concentrations in all tests, but these values were not notable. The results of this study showed that using M. anisopliae var. acridum diluted in gasoline can be effective on nymphal instars of locust, D. albidula, in two continuous years.  相似文献   
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