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91.
Coronavirus disease 2019 (COVID-19) is a systemic inflammatory condition with high mortality that may benefit from personalized medicine and high-precision approaches. COVID-19 patient plasma was analysed with targeted proteomics of 1161 proteins. Patients were monitored from Days 1 to 10 of their intensive care unit (ICU) stay. Age- and gender-matched COVID-19-negative sepsis ICU patients and healthy subjects were examined as controls. Proteomic data were resolved using both cell-specific annotation and deep-analysis for functional enrichment. COVID-19 caused extensive remodelling of the plasma microenvironment associated with a relative immunosuppressive milieu between ICU Days 3–7, and characterized by extensive organ damage. COVID-19 resulted in (1) reduced antigen presentation and B/T-cell function, (2) increased repurposed neutrophils and M1-type macrophages, (3) relatively immature or disrupted endothelia and fibroblasts with a defined secretome, and (4) reactive myeloid lines. Extracellular matrix changes identified in COVID-19 plasma could represent impaired immune cell homing and programmed cell death. The major functional modules disrupted in COVID-19 were exaggerated in patients with fatal outcome. Taken together, these findings provide systems-level insight into the mechanisms of COVID-19 inflammation and identify potential prognostic biomarkers. Therapeutic strategies could be tailored to the immune response of severely ill patients.  相似文献   
92.
In recent years, black ginseng, a new type of processed ginseng product, has attracted the attention of scholars globally. Ginsenoside and ginseng polysaccharide, the main active substances of black ginseng, have been shown to carry curative effects for many diseases. This article focuses on the mechanism of their action in anti-inflammatory response, which is mainly divided into three aspects: activation of immune cells to exert immune regulatory response; participation in inflammatory response-related pathways and regulation of the expression level of inflammatory factors; effect on the metabolic activity of intestinal flora. This study identifies active anti-inflammatory components and an action mechanism of black ginseng showing multi-component, multi-target, and multi-channel characteristics, providing ideas and a basis for a follow-up in-depth study of its specific mechanism.  相似文献   
93.
The gene (alyVI) encoding an alginate lyase of marine bacterium Vibrio sp. QY101, which was isolated from a decaying thallus of Laminaria, was cloned using a strategy of combined degenerate PCR and long range-inverse PCR (LR-IPCR), then sequenced and expressed in Escherichia coli. Gene alyVI was composed of a 1014 bp open reading frame (ORF) encoding 338 amino acid residues. The calculated molecular mass of alyVI product is 38.4 kDa, but a signal peptide is cleaved off, leaving a mature protein of 34 kDa. AlyVI was purified from culture supernatants to electrophoretic homogeneity using affinity chromatography. AlyVI was most active at pH 7.5 and 40 degrees C in the presence of 1 mM ZnCl2. A nine-amino-acid consensus region (YXRESLREM), which was only found in polyguluronate lyases, was also observed in the amino-terminal region of AlyVI. However, AlyVI could degrade both M block and G block. These results indicate that a novel alginate lyase-encoding gene has been cloned.  相似文献   
94.
The anatomy of the arthropod Squamacula clypeata Hou and Bergström, 1997 from the Lower Cambrian Chengjiang Lagersta¨tte is redescribed based on four newly excavated specimens. The new material was collected from localities recently discovered in the Kunming area, Yunnan Province, south-west China, and preserves remarkable details of the ventral morphology, revealed by preparation. Squamacula clypeata is dorsoventrally flattened and rounded in outline. The cephalon was covered by a wide, short shield, with a large doublure and a pair of uniramous antennae on the ventral side. The thorax consists of nine somites, each protected by a tergite and carrying at least one pair of biramous limbs. The pygidium is covered with a small rounded tergum. The endopod is segmented, equipped with short spines on the inner margin of the coxa and a claw-like structure distally, and the exopod flap-like, fringed with setae. The limbs in the pygidium are like those in the thorax in shape. Squamacula was most probably a nektobenthic predator. The spinose endopod could walk, grasp and grind. The large flap-like exopod was adapted for swimming and respiration. Its affinities lie with the Arachnomorpha, but the relationships with other known taxa remain ambiguous.  相似文献   
95.
 中药固真方对一些与细胞增殖有关基因表达的影响姚明忠,顾文聪,丁卫,韩志芬,杜国光(上海中医药大学生物化学教研室,上海200032)(北京医科大学生物化学与分子生物学系,北京100083)中药固真方(VRF)具有补肾益精、延缓衰老的作用[1].能提高成...  相似文献   
96.
The overexpression of some human proteins can cause interference with the Ras signal transduction pathway in the yeast Saccharomyces cerevisiae. The functional block is located at the level of the effector itself, since these proteins do not suppress activating mutations further downstream in the same pathway. We now demonstrate, with in vivo and in vitro experiments, that the protein encoded by one human cDNA (clone 99) can interact directly with yeast Ras2p and with human H-Ras protein, and we have named this gene rin1 (Ras interaction/interference). The interaction between Ras and Rin1 is enhanced when Ras is bound to GTP. Rin1 is not able to interact with either an effector mutant or a dominant negative mutant of H-Ras. Thus, Rin1 displays a human H-Ras interaction profile that is the same as that seen for Raf1 and yeast adenylyl cyclase, two known effectors of Ras. Moreover, Raf1 directly competes with Rin1 for binding to H-Ras in vitro. Unlike Raf1, however, the Rin1 protein resides primarily at the plasma membrane, where H-Ras is localized. These data are consistent with Rin1 functioning in mammalian cells as an effector or regulator of H-Ras.  相似文献   
97.
98.
The crystal structure of cholestanyl n-octanoate (caprylate) (C35H62O2) is monoclinic with space group A2 and cell dimensions a = 10.103(7), b = 7.646(7), c = 87.63(7) A, beta = 90.51(6) degrees; Z = 8 [two molecules (A, B) in asymmetric unit], V = 6769 A3, Dc = 1.010 g cm-3. Integrated X-ray intensities for 3798 reflections with I greater than 2 sigma (I) were measured with a rotating anode diffractometer at room temperature. The structure was determined using direct methods. Block diagonal least squares refinement gave R = 0.111. Molecules A and B have almost fully extended conformations, but differ significantly in the rotation about the ester bond and in the C17 chains. The molecular packing in the crystal structure of cholestanyl caprylate consists of stacked bilayers each having d002 = 43.8 A in thickness and within each bilayer, cholestanols pack with cholestanols and caprylate chains pack with caprylate chains. The crystal structure is very similar to that of cholesteryl myristate but is quite different from that of cholesteryl caprylate. The phase equilibria of the cholestanyl caprylate/cholesteryl caprylate binary system have been shown to involve limited mutual solubility of the two components and to have a eutectic point at 73% cholestanyl caprylate. The cholesteric mesophase is monotropic at all compositions except for a narrow range near the eutectic point where it is enantiotropic.  相似文献   
99.
100.
An expression vector for G-CSF, pASLB3-3, was constructed and introduced into Namalwa KJM-1 cells (Hosoi et al., 1988), and cells resistant to 100 nM of methotrexate (MTX) were obtained. Among them, the highest producer, clone SC57, was selected and the productivity of this clone was further characterized. The maximal production of G-CSF was at the most 1.8 g/ml/day using a 25 cm2 tissue culture flask, even though the cell number was above 7×105 cells/ml. The limiting factors at high density were analyzed as the deficiency of nutrients, such as glucose, cysteine and serine, and pH control. The depression of specific G-CSF productivity per cell under the batch culture conditions was overcome by using a perfusion culture system, BiofermenterTM (Sato, 1983) with modifications of nutrients supplementation by a dialysis membrane and/or dissolved oxygen (DO) supplementation by microsilicone fibers. ITPSGF medium was modified to elevate concentrations of amino acids and glucose by 2.0- and 2.5-times, respectively. Under the control of pH at 7.4 and DO at 3 ppm, the specific G-CSF productivity was not depressed even at high cell density (above 1×107 cells/ml), and the amount of G-CSF reached 41 g/ml. These results indicated the possibility of finding the optimum culture conditions for the production of recombinant proteins by Namalwa KJM-1 cells.Abbreviations ABTS 2,2-Azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid - BSA Bovine Serum Albumin - BSA-PBS Phosphate-buffered Saline without Ca2+ and Mg2+ containing Bovine Serum Albumin - dhfr Dihydrofolate Reductase - DO Dissolved Oxygen - G-CSF Granulocyte Colony-stimulating Factor - HEPES 4-(2-Hydroxyethyl)-1-piperazineethansulfonic Acid - IFN Interferon - MTX Methotrexate - PBS(-) Phosphate-buffered saline without Ca2+ and Mg2+ - Tween-PBS Phosphate-buffered saline without Ca2+ and Mg2+ containing 0.05% of Tween 20  相似文献   
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