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1.
《Cancer cell》2022,40(10):1223-1239.e6
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Plant protection products may affect the behavior of organisms which are not a target of control. The effect of Karate Zeon 050 CS (λ-Cyhalothrin -based insecticide; λ-CBI) and Amistar 250 SC (Azoxystrobin-based fungicide; ABF) was determined on Apis mellifera worker attraction towards their own colony odour, along with temperature preferences. Bees exposed to pesticides prefer the environment with the odour of their nest less often than the control group, and that insecticide-treated bees chose warmer environments than the control insects. The observed differences in the bees, especially with attraction towards their own colony, were dependent on the time of day. Chromatographic analyses indicated that λ-Cyhalothrin elimination was half that of Azoxystrobin in bee organisms, and both agents retarded each other’s clearance. Mathematical modeling estimated that despite a relatively high disappearance rate, both compounds might have been bio-accumulated at relatively high level.  相似文献   
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目的:探究聚二磷酸腺苷核糖多聚酶1[poly (ADP-ribose) polymerase 1,PARP1]对黑素瘤细胞克隆形成的影响及可能的作用机制。方法:在黑素瘤A2058细胞系中利用小干扰RNA干涉PARP1表达水平,利用平板克隆形成实验观察干涉PARP1对黑素瘤细胞克隆形成的影响。提取PARP1干涉片段及对照片段转染细胞的总RNA进行全基因组表达谱芯片检测。Realtime RT-PCR对部分差异性基因进行验证。应用DAVID数据库对差异性基因进行GO及KEGG通路富集分析。Realtime RT-PCR对富集分析结果中可疑靶基因进行验证。结果:干涉PARP1表达可显著抑制黑素瘤细胞克隆形成。全基因组芯片结果显示干涉PARP1表达可引起128个基因表达上调,77个基因表达下调。通过Realtime RT-PCR对部分差异表达基因进行验证,结果表明与芯片筛选结果一致。GO和KEGG富集分析结果显示PARP1调控的差异性表达基因在生物学功能及参与的信号通路中存在部分交集,即MAPK信号通路及其正向调控机制。双特异性磷酸酶5(DUSP5)作为MAPK通路中的抑制分子,Realtime RT-PCR证实干涉PARP1可促进其表达水平升高。结论:干涉PARP1可能通过促进DUSP5表达从而抑制MAPK信号通路活性,进而发挥抑制黑素瘤细胞克隆形成的作用。  相似文献   
4.
The analysis of mitochondrial (mt)DNA is a powerful tool in forensic genetics when nuclear markers fail to give results or maternal relatedness is investigated. The mtDNA control region (CR) contains highly condensed variation and is therefore routinely typed. Some samples exhibit an identical haplotype in this restricted range. Thus, they convey only weak evidence in forensic queries and limited phylogenetic information. However, a CR match does not imply that also the mtDNA coding regions are identical or samples belong to the same phylogenetic lineage. This is especially the case for the most frequent West Eurasian CR haplotype 263G 315.1C 16519C, which is observed in various clades within haplogroup H and occurs at a frequency of 3–4% in many European populations.In this study, we investigated the power of massively parallel complete mtGenome sequencing in 29 Italian samples displaying the most common West Eurasian CR haplotype – and found an unexpected high diversity. Twenty-eight different haplotypes falling into 19 described sub-clades of haplogroup H were revealed in the samples with identical CR sequences. This study demonstrates the benefit of complete mtGenome sequencing for forensic applications to enforce maximum discrimination, more comprehensive heteroplasmy detection, as well as highest phylogenetic resolution.  相似文献   
5.
Emetic and diarrheal toxins produced by endospore-forming Bacillus cereus causes a huge loss to dairy industry. Milk is the suitable medium for the growth of B. cereus. The pathogen is of particular concern in the dairy industry because in spite of aggressive cleaning practices performed by the dairy industry, it is impossible to destroy these hydrophobic spores which adhere to the pipelines of the dairy-processing plant and further these spores may also form biofilms in the milk. The reporting rate of illness caused by B. cereus is vague, usually due to the short duration of (<24?h) the diarrheal and emetic syndromes. The study of toxins production by B. cereus isolates is essential to better determine the methods of controlling these toxins in dairy industry.  相似文献   
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Staphylococcus aureus and other Gram negative bacteria produce small colony variants (SCV) which usually emerge after exposure to antimicrobials. They cause repeated infections, treatment failures and often pass unnoticed during cultures due to unusual appearance and incomplete incubation. This infectious disease grand round highlights a similar clinical case with atypical history and appearance of a SCV of S. aureus and why prolonged incubation is necessary for aspirates from patients with recurrent infections like abscesses.  相似文献   
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Several studies have investigated the association of Group‐specific Component (GC) gene, also known as vitamin D‐binding protein (VDBP), and various respiratory disorder susceptibility with conflicting results. In this sense, we aimed to investigate whether rs7041 and rs4588 variants confer susceptibility to bronchial asthma in a sample of an Egyptian population and to elucidate by in silico analysis the structural and functional impact of these variants. Group‐specific Component polymorphisms rs7041 and rs4588 were genotyped in 192 Egyptian children and adolescents (96 with asthma and 96 healthy controls) by TaqMan single nucleotide polymorphism genotyping assay. The rs7041 GG genotype showed a significantly elevated frequency among patients under codominant, dominant, recessive and allelic models where the patient group had greater carriage rate of G allele [OR 2.15, CI 95% (1.32‐3.50; P = 0.002)], while rs4588 CA and AA genotypes were found to be protective genotypes with controls showing a greater carriage rate of A allele [OR 0.52, CI 95% (0.30 ‐ 0.90; P = 0.02)]. Three haplotype allele combinations were identified with frequencies of GC (44.3%), TC (31.3%) and TA (24.5%) in the total study population. GC haplotype was shown to be more frequent in controls, while TC and TA haplotypes were more predominant in the patient group. Only rs7041 variant showed a significant association with family history and pubertal status. In conclusion, both study GC variants could be implicated in childhood bronchial asthma pathogenesis; rs7041 GG genotype and G allele increased asthma risk while rs4588 AA genotype and A allele conferred protection in the study population.  相似文献   
10.
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