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941.
Coliphage N4 is a lytic bacteriophage discovered nearly half a century ago, and it was considered to be a “genetic orphan” until very recently, when several additional N4-like phages were discovered to infect nonenteric bacterial hosts. Interest in this genus of phages is stimulated by their unique genetic features and propagation strategies. To better understand the ecology of N4-like phages, we investigated the diversity and geographic patterns of N4-like phages by examining 56 Chesapeake Bay viral communities, using a PCR-clone library approach targeting a diagnostic N4-like DNA polymerase gene. Many new lineages of N4-like phages were found in the bay, and their genotypes shift from the lower to the upper bay. Interestingly, signature sequences of N4-like phages were recovered only from winter month samples, when water temperatures were below 4°C. An analysis of existing metagenomic libraries from various aquatic environments supports the hypothesis that N4-like phages are most prolific in colder waters. In particular, a high number of N4-like phages were detected in Organic Lake, Antarctica, a cold and hypersaline system. The prevalence of N4-like phages in the cold biosphere suggests these viruses possess yet-to-be-determined mechanisms that facilitate lytic infections under cold conditions. 相似文献
942.
Bastian Th Eichenberger YinXiu Zhan Markus Rempfler Luca Giorgetti Jeffrey
A Chao 《Nucleic acids research》2021,49(13):7292
Detection of diffraction-limited spots in single-molecule microscopy images is traditionally performed with mathematical operators designed for idealized spots. This process requires manual tuning of parameters that is time-consuming and not always reliable. We have developed deepBlink, a neural network-based method to detect and localize spots automatically. We demonstrate that deepBlink outperforms other state-of-the-art methods across six publicly available datasets containing synthetic and experimental data. 相似文献
943.
Xiang Zhou Yu Feng Zhoubing Zhan Jianchang Chen 《The Journal of biological chemistry》2014,289(42):28827-28834
Accumulating evidence has demonstrated that hydrogen sulfide (H2S) plays critical roles in the pathogenesis of chronic kidney diseases. This study was designed to investigate whether H2S has protective effects against diabetic nephropathy. Diabetic rats were induced by intraperitoneal injection of streptozotocin and administrated with H2S donor NaHS for 12 weeks. Rat glomerular mesangial cells were pretreated with NaHS or MAPK inhibitors (U0126, SP600125, and SB203580) prior to high glucose exposure, and cell proliferation was determined. Our findings suggest that H2S can improve renal function and attenuate glomerular basement membrane thickening, mesangial matrix deposition, and renal interstitial fibrosis in diabetic rats. H2S was found to reduce high glucose-induced oxidative stress by activating the Nrf2 antioxidant pathway and to exert anti-inflammatory effects by inhibiting NF-κB signaling. In addition, H2S reduced high glucose-induced mesangial cell proliferation by blockade of MAPK signaling pathways. Moreover, H2S was also found to inhibit the renin-angiotensin system in diabetic kidney. In conclusion, our study demonstrates that H2S alleviates the development of diabetic nephropathy by attenuating oxidative stress and inflammation, reducing mesangial cell proliferation, and inhibiting renin-angiotensin system activity. 相似文献
944.
Shaoxiang Wang Xiao Wang Zhan Du Yuting Liu Dane Huang Kai Zheng Kaisheng Liu Yi Zhang Xueyun Zhong Yifei Wang 《Biochemical and biophysical research communications》2014
17-Allylamino-17-demethoxygeldanamycin (17-AAG), a typical Hsp90 inhibitor derived from geldanamycin (GA), has entered Phase III clinical trials for cancer therapy. However, it has several significant limitations such as poor solubility, limited bioavailability and unacceptable hepatotoxicity. In this study, the anticancer activity and mechanism of SNX-25a, a novel Hsp90 inhibitor, was investigated comparing with that of 17-AAG. We showed that SNX-25a triggered growth inhibition more sensitively than 17-AAG against many human cancer cells, including K562, SW-620, A375, Hep-2, MCF-7, HepG2, HeLa, and A549 cell lines, especially at low concentrations (<1 μM). It showed low cytotoxicity in L-02, HDF and MRC5 normal human cells. Compared with 17-AAG, SNX-25a was more potent in arresting the cell cycle at G2 phase, and displayed more potent effects on human cancer cell apoptosis and Hsp90 client proteins. It also exhibited a stronger binding affinity to Hsp90 than 17-AAG using molecular docking. Considering the superiority effects on Hsp90 affinity, cell growth, cell cycle, apoptosis, and Hsp90 client proteins, SNX-25a is supposed as a potential anticancer agent that needs to be explored in detail. 相似文献
945.
Unconventional myosin VIIA (Myo7a) has been known to associate with hereditary deafness. Here we present a novel function of Myo7a by identifying that Myo7a directly interacts with integrin β5 subunit and regulates cell adhesion and motility in an integrin-dependent manner. We found that Myo7a bound to the cytoplasmic tail of integrin β5. Further, we pinpointed an integrin-binding domain at F3 of the first FERM domain and F1 of the second FERM domain. Functionally, Myo7a-induced cell adhesion and migration were mediated by integrin αvβ5. These findings indicated that Myo7a interacts with integrin β5 and selectively promotes integrin αvβ5-mediated cell migration. 相似文献
946.
Jun-Kun Zhan Yan-Jiao WangYi Wang Zhi-Yong TangPan Tan Wu HuangYou-Shuo Liu 《Experimental cell research》2014
Vascular calcification is common in patients with peripheral artery diseases and coronary artery diseases. The osteoblastic differentiation of vascular smooth muscle cells (VSMCs) contributes significantly to vascular calcification. Adiponectin has been demonstrated to exert a protective effect in osteoblastic differentiation of VSMCs through regulating mTOR activity. However, the upstream and downstream signaling molecules of adiponectin-regulated mTOR signaling have not been identified in VSMCs with osteoblastic differentiation. In this study, the VSMC differentiation model was established by beta-glycerophosphate (β-GP) induction. The mineralization was identified by Alizarin Red S staining. Protein expression and phosphorylation were detected by Western blot or immunofluorescence. Adiponectin attenuated osteoblastic differentiation and mineralization of β-GP-treated VSMCs. Adiponectin inhibited osteoblastic differentiation of VSMCs through increasing the level of p-AMPKα. Pretreatment of VSMCs with AMPK inhibitor blocked while AMPK activator enhanced the effect of adiponectin on osteoblastic differentiation of VSMCs. Adiponectin upregulated TSC2 expression and downregulated mTOR and S6K1 phosphorylation in β-GP-treated VSMCs. Adiponectin treatment significantly attenuates the osteoblastic differentiation and calcification of VSMCs through modulation of AMPK–TSC2–mTOR–S6K1 signal pathway. 相似文献
947.
948.
949.
Seydou Sylla Yan‐Long Cong Yi‐Xue Sun Gui‐Lian Yang Xue‐Mei Ding Zhan‐Qing Yang Yu‐Long Zhou Minnan Yang Chun‐Feng Wang Zhuang Ding 《Microbiology and immunology》2014,58(7):398-408
Post‐weaning multisystemic wasting syndrome (PMWS) associated with porcine circovirus type 2 (PCV2) has caused the swine industry significant health challenges and economic damage. Although inactivated and subunit vaccines against PMWS have been used widely, so far no DNA vaccine is available. In this study, with the aim of exploring a new route for developing a vaccine against PCV2, the immunogenicity of a DNA vaccine was evaluated in mice. The pEGFP‐N1 vector was used to construct a PCV2 Cap gene recombinant vaccine. To assess the immunogenicity of pEGFP‐Cap, 80 BALB/c mice were immunized three times at 2 weekly intervals with pEGFP‐Cap, LG‐strain vaccine, pEGFP‐N1 vector or PBS and then challenged with PCV2. IgG and cytokines were assessed by indirect ELISA and ELISA, respectively. Specimens stained with hematoxylin and eosin (HE) and immunohistochemistry (IHC) techniques were examined histopathologically. It was found that vaccination of the mice with the pEGFP‐Cap induced solid protection against PCV2 infection through induction of highly specific serum IgG antibodies and cytokines (IFN‐γ and IL‐10), and a small PCV2 viral load. The mice treated with the pEGFP‐Cap and LG‐strain developed no histopathologically detectable lesions (HE stain) and IHC techniques revealed only a few positive cells. Thus, this study demonstrated that recombinant pEGFP‐Cap substantially alleviates PCV2 infection in mice and provides evidence that a DNA vaccine could be an alternative to PCV2 vaccines against PMWS. 相似文献
950.
Cosuppression of RBCS3B in Arabidopsis leads to severe photoinhibition caused by ROS accumulation 总被引:1,自引:0,他引:1
Gao-Miao Zhan Rong-Jun Li Zhi-Yong Hu Jing Liu Lin-Bin Deng Shi-You Lu Wei Hua 《Plant cell reports》2014,33(7):1091-1108