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41.
Jin Wei Mia Madel Alfajaro Peter C. DeWeirdt Ruth E. Hanna William J. Lu-Culligan Wesley L. Cai Madison S. Strine Shang-Min Zhang Vincent R. Graziano Cameron O. Schmitz Jennifer S. Chen Madeleine C. Mankowski Renata B. Filler Neal G. Ravindra Victor Gasque Fernando J. de Miguel Ajinkya Patil Huacui Chen Craig B. Wilen 《Cell》2021,184(1):76-91.e13
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42.
Yunfan Sun Liang Wu Yu Zhong Kaiqian Zhou Yong Hou Zifei Wang Zefan Zhang Jiarui Xie Chunqing Wang Dandan Chen Yaling Huang Xiaochan Wei Yinghong Shi Zhikun Zhao Yuehua Li Ziwei Guo Qichao Yu Liqin Xu Jia Fan 《Cell》2021,184(2):404-421.e16
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43.
We isolated a recombinant H9N2 avian influenza virus (AIV) from fresh egret feces in the Ardeidae protection region of the Dongting Lake wetland area in China, and it was designated A/Egret/Hunan/1/2012(H9N2). This is the first report of isolating H9N2 AIV from wild birds in the Dongting Lake wetland. Its eight gene segments are generated by reassortment of gene segments of different AIV subtypes. These results are helpful for understanding the epidemiology and evolution of AIV in wild birds during migration. 相似文献
44.
Inflammatory responses mediated by activated microglia play a pivotal role in the pathogenesis of human immunodeficiency virus type 1 (HIV-1)-associated neurocognitive disorders. Studies on identification of specific targets to control microglia activation and resultant neurotoxic activity are imperative. Increasing evidence indicate that voltage-gated K+ (Kv) channels are involved in the regulation of microglia functionality. In this study, we investigated Kv1.3 channels in the regulation of neurotoxic activity mediated by HIV-1 glycoprotein 120 (gp120)-stimulated rat microglia. Our results showed treatment of microglia with gp120 increased the expression levels of Kv1.3 mRNA and protein. In parallel, whole-cell patch-clamp studies revealed that gp120 enhanced microglia Kv1.3 current, which was blocked by margatoxin, a Kv1.3 blocker. The association of gp120 enhancement of Kv1.3 current with microglia neurotoxicity was demonstrated by experimental results that blocking microglia Kv1.3 attenuated gp120-associated microglia production of neurotoxins and neurotoxicity. Knockdown of Kv1.3 gene by transfection of microglia with Kv1.3-siRNA abrogated gp120-associated microglia neurotoxic activity. Further investigation unraveled an involvement of p38 MAPK in gp120 enhancement of microglia Kv1.3 expression and resultant neurotoxic activity. These results suggest not only a role Kv1.3 may have in gp120-associated microglia neurotoxic activity, but also a potential target for the development of therapeutic strategies. 相似文献
45.
E. P. Isakova Yu. I. Deryabina N. N. Gessler T. A. Belozerskaya Ya. M. Rabinovich 《Applied Biochemistry and Microbiology》2010,46(3):318-323
Cell respiratory activity of protoplasts obtained from the wild type of Neurospora crassa and photoreceptor complex WCC—white collar 1 (wc-1) and white collar 2 (wc-2)—mutants of Neurospora crassa strains was investigated. Respiration inhibition by KCN in the presence of 25 mM succinate was similar in all strains and
did not exceed 83–85% against control. The significant induction of KCN-resistant respiratory pathway occurred under 1% glucose
oxidation in wc-1 and wc-2 mutants if compared with the wild type strains. The inhibitors of the main (cytochrome) pathway of electron transfer in mitochondria—1
mM KCN and antimycin A (4 μg/ml)—blocked the respiration rate of the protoplasts from N. crassa wild type by 75%, while the cell respiration of wc-1 and wc-2 strains was suppressed by approximately 50%. The specific inhibitor of alternative oxidase—10 mM salicylhydroxamic acid (SHAM)—in
combination with the blockers of mitochondrial electron transfer chain caused the total suppression of respiratory activity
of protoplasts in all studied strains. It is supposed that an increase of KCN-resistance in WCC mutants under glucose oxidation
is connected with alternative oxidase activation as the result of failure in reception and signal transduction of active oxygen
species. 相似文献
46.
Primary open-angle glaucoma (POAG) is one of the leading causes of blindness worldwide. The association between the APOE ε2/ε3/ε4 polymorphism and the risk of POAG has been widely reported, but the results of previous studies remain controversial. To comprehensively evaluate the APOE ɛ2/ɛ3/ε4 polymorphism on the genetic risk for POAG, we performed a systematic review and meta-analysis of previously published studies. The PubMed and Web of Science databases were systematically searched to identify relevant studies. Data were extracted from these studies and odds ratios with corresponding 95% confidence intervals were computed to estimate the strength of the association. Stratified analyses according to ethnicity and sensitivity analyses were also conducted for further confirmation. A total of nine studies were eligible for the meta-analysis, and these studies included data on 1928 POAG cases and 1793 unrelated match controls. The combined results showed that there were no associations between the APOE ε2/ε3/ε4 polymorphism and POAG risk in any of the 10 comparison models. The analysis that was stratified by ethnicity subgroups also failed to reveal a significant association. The sensitivity analysis confirmed the stability and reliability of the findings. There was no risk of publication bias. Our meta-analysis provides strong evidence that the APOE ε2/ε3/ε4 polymorphism is not associated with POAG susceptibility in any populations. 相似文献
47.
The discrimination of the angular velocity of ventrodorsal and dorsoventral movement of an acoustic image was studied in nine test subjects. The experiments were performed using an apparent movement produced by consecutive activation of loudspeakers located along an arc in the vertical plane. The differential thresholds were measured by the minimum increment method. As the velocity of an acoustic image movement in opposite directions increased, the values of its mean absolute differential thresholds increased monotonically. Regression lines plotted by linear approximation of these values did not differ significantly. 相似文献
48.
L. G. Akhmetzyanova A. A. Saveliev S. Yu. Selivanovskaya 《Contemporary Problems of Ecology》2012,5(6):554-558
This paper presents an algorithm for determining the content of oil products in remediated soil that is safe for plants and microorganisms. The algorithm includes laboratory modeling of the remediation of soil samples that contain different amounts of soil products, determination of the biological parameters that provide the integral characterization of the soil state in these samples, and analysis of the results on the basis of odds-ratio statistics, which allows one to determine the content of oil products, starting from which the state of an oil-contaminated soil has no significant difference from a control soil. 相似文献
49.
Cell division in cell suspension cultures can be completely blocked by the growth retardant tetcyclacis at a concentration of 10-4 mol l-1. In rice cells it has been demonstrated that the growth inhibition can be completely overcome by application of cholesterol independent of the duration of pretreatment with tetcyclacis. In suspension cultures of maize and soybean, too, the effect of tetcyclacis on cell division was neutralized by adding cholesterol. Other plant sterols, stigmasterol, campesterol and sitosterol were active in a decreasing order. Modifications in the cholesterol perhydro-cyclopentanophenanthrene-ring system indicate that the hydroxyl group at C-3 and the double bond between C-5 and C-6 in ring B are required for the activity. In contrast, gibberellic acid as well as ent-kaurenoic acid could not compensate retardant effects. Likewise, tetcyclasis did not change the level of gibberellins in rice cells as shown by radioimmunoassay. Thus, it is concluded that in cell suspension cultures sterols play a more important role in cell division than gibberellins.Abbreviation GAx
gibberelin Ax 相似文献
50.
Ai‐Xin Song Chen‐Jie Zhou Xiao Guan Kong‐Hung Sze Hong‐Yu Hu 《Protein science : a publication of the Protein Society》2010,19(5):1104-1109
DC‐UbP/UBTD2 is a ubiquitin (Ub) domain‐containing protein first identified from dendritic cells, and is implicated in ubiquitination pathway. The solution structure and backbone dynamics of the C‐terminal Ub‐like (UbL) domain were elucidated in our previous work. To further understand the biological function of DC‐UbP, we then solved the solution structure of the N‐terminal domain of DC‐UbP (DC‐UbP_N) and studied its Ub binding properties by NMR techniques. The results show that DC‐UbP_N holds a novel structural fold and acts as a Ub‐binding domain (UBD) but with low affinity. This implies that the DC‐UbP protein, composing of a combination of both UbL and UBD domains, might play an important role in regulating protein ubiquitination and delivery of ubiquitinated substrates in eukaryotic cells. 相似文献