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991.
Tang  Pei-jia  Zhang  Zhi-hui  Niu  Li-li  Gu  Cheng-bo  Zheng  Wen-yi  Cui  Hai-chao  Yuan  Xiao-han 《Biotechnology letters》2021,43(7):1371-1383

The study aimed to characterize a novel vitexin-producing endophytic fungus Fusarium solani G6 from Cajanus cajan, improve its capability for producing vitexin and evaluate its osteoblastic proliferation activity. A total of 153 endophytic fungi, classified into 6 genera, were isolated from C. cajan. Among them, only one strain, endophyte G6 identified as Fusarium solani, was found to produce vitexin. After the optimization of fermentation conditions, the highest vitexin yield (18.72 mg/L) for the strain was observed in PDB liquid medium containing 20.54 g/L of glucose and 8.90 g/L of ammonium sulfate, at an initial medium pH of 5.1 and at 28 °C for 6 days of cultivation. Moreover, the fungal vitexin exhibited notable osteoblastic proliferation stimulating activity. A novel vitexin-producing endophytic fungus F. solani G6 was characterized from C. cajan for the first time. The findings highlighted its potential use for large-scale production of vitexin and might have a promising use as therapeutic agent for osteoporosis.

  相似文献   
992.
Kang  Bin  Pecl  Gretta T.  Lin  Longshan  Sun  Peng  Zhang  Peidong  Li  Yuan  Zhao  Linlin  Peng  Xin  Yan  Yunrong  Shen  Chunyan  Niu  Wentao 《Reviews in Fish Biology and Fisheries》2021,31(3):599-629
Reviews in Fish Biology and Fisheries - Globally, climate change impacts on marine ecosystems are evident in physical, chemical, and biological processes, and are generally more extensive in faster...  相似文献   
993.
Copper pollution poses a serious threat to the aquatic environment; however, in situ analytical methods for copper monitoring are still scarce. In the current study, Escherichia coli Rosetta was genetically modified to express OprF and ribB with promoter Pt7 and PcusC, respectively, which could synthesize porin and senses Cu2+ to produce riboflavin. The cell membrane permeability of this engineered strain was increased and its riboflavin production (1.45–3.56 μM) was positively correlated to Cu2+ (0–0.5 mM). The biosynthetic strain was then employed in microbial fuel cell (MFC) based biosensor. Under optimal operating parameters of pH 7.1 and 37°C, the maximum voltage (248, 295, 333, 352, and 407 mV) of the constructed MFC biosensor showed a linear correlation with Cu2+ concentration (0.1, 0.2, 0.3, 0.4, 0.5 mM, respectively; R2 = 0.977). The continuous mode testing demonstrated that the MFC biosensor specifically senses Cu2+ with calculated detection limit of 28 μM, which conforms to the common Cu2+ safety standard (32 μM). The results obtained with the developed biosensor system were consistent with the existing analytical methods such as colorimetry, flame atomic absorption spectrometry, and inductively coupled plasma optical emission spectrometry. In conclusion, this MFC‐based biosensor overcomes the signal conversion and transmission problems of conventional approaches, providing a fast and economic analytical alternative for in situ monitoring of Cu2+ in water.  相似文献   
994.
995.
HIV-1 functional cure requires sustained viral suppression without antiretroviral therapy. While effector-memory CD8+ T lymphocytes are essential for viremia control, few vaccines elicit such cellular immunity that could be potently recalled upon viral infection. Here, we investigated a program death-1 (PD1)-based vaccine by fusion of simian immunodeficiency virus capsid antigen to soluble PD1. Homologous vaccinations suppressed setpoint viremia to undetectable levels in vaccinated macaques following a high-dose intravenous challenge by the pathogenic SHIVSF162P3CN. Poly-functional effector-memory CD8+ T cells were not only induced after vaccination, but were also recalled upon viral challenge for viremia control as determined by CD8 depletion. Vaccine-induced effector memory CD8+ subsets displayed high cytotoxicity-related genes by single-cell analysis. Vaccinees with sustained viremia suppression for over two years responded to boost vaccination without viral rebound. These results demonstrated that PD1-based vaccine-induced effector-memory CD8+ T cells were recalled by AIDS virus infection, providing a potential immunotherapy for functional cure.  相似文献   
996.
Zhou  Chen  Huo  Yiping  Guo  Yiyuan  Niu  Qiqiang 《Plasmonics (Norwell, Mass.)》2021,16(5):1735-1743
Plasmonics - A metal-insulator-metal (MIM) waveguide consisting of two stub resonators and a ring resonator is proposed, which can be used as refractive index sensor and stop-band filter at the...  相似文献   
997.
Jiang  Teng  Diao  Xiaoli  Ding  Meili  Niu  Xiao  Wang  Chao  Qi  Yan  Jia  Wei  Pang  Lijuan  Hu  Wenhao  Zou  Hong  Li  Feng 《Journal of molecular histology》2021,52(3):539-544
Journal of Molecular Histology - Both clear cell renal carcinoma (ccRCC) and clear cell carcinoma of the ovary (CCOC) have a clear cytoplasmic morphological feature, hence it is difficult to...  相似文献   
998.
Niu  Lijun  Chen  Lihong  Luo  Yanhua  Huang  Wenkao  Li  Yunsheng 《BMC anesthesiology》2021,21(1):1-6
This case demonstrates the severe electrolyte derangements that may present after a common therapy such as a bowel preparation for an outpatient procedure and the rare yet potential detrimental outcomes of those abnormalities. It also highlights the implications of long QT syndrome regarding pharmacology and treatment. We present a case of 48 year-old female with severe electrolyte derangements and long QT syndrome (LQTS) leading to Torsades de Pointes (TdP), pulseless ventricular fibrillation, and unsynchronized defibrillation in the post anesthesia care unit (PACU) after uneventful upper and lower endoscopy. This led to an unanticipated intensive care unit admission for aggressive electrolyte repletion, cardiology consultation, and implantable cardioverter defibrillator (ICD) placement. This is a rare presentation after an outpatient procedure that would have had a detrimental outcome if not promptly diagnosed and treated appropriately. Therefore, we aim to provide further insight into the diagnosis and treatment of severe hypokalemia and long QT syndrome resulting in Torsades de Pointes and ventricular fibrillation.  相似文献   
999.
1000.
Active DNA demethylation is critical for altering DNA methylation patterns and regulating gene expression. The 5‐methylcytosine DNA glycosylase/lyase ROS1 initiates a base‐excision repair pathway for active DNA demethylation and is required for the prevention of DNA hypermethylation at 1 000s of genomic regions in Arabidopsis. How ROS1 is regulated and targeted to specific genomic regions is not well understood. Here, we report the discovery of an Arabidopsis protein complex that contains ROS1, regulates ROS1 gene expression, and likely targets the ROS1 protein to specific genomic regions. ROS1 physically interacts with a WD40 domain protein (RWD40), which in turn interacts with a methyl‐DNA binding protein (RMB1) as well as with a zinc finger and homeobox domain protein (RHD1). RMB1 binds to DNA that is methylated in any sequence context, and this binding is necessary for its function in vivo. Loss‐of‐function mutations in RWD40, RMB1, or RHD1 cause DNA hypermethylation at several tested genomic regions independently of the known ROS1 regulator IDM1. Because the hypermethylated genomic regions include the DNA methylation monitoring sequence in the ROS1 promoter, plants mutated in RWD40, RMB1, or RHD1 show increased ROS1 expression. Importantly, ROS1 binding to the ROS1 promoter requires RWD40, RMB1, and RHD1, suggesting that this complex dictates ROS1 targeting to this locus. Our results demonstrate that ROS1 forms a protein complex with RWD40, RMB1, and RHD1, and that this novel complex regulates active DNA demethylation at several endogenous loci in Arabidopsis.  相似文献   
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