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91.
Lipid peroxidation (LPX) can play an important role in development of functional and pathological changes of maternal tissues in the course of pregnancy and delivery. LPX products were measured as thiobarbituric acid reacting substances (TBARS), using malondialdehyde as the standard solution. Actual TBARS determined in maternal post-delivery plasma (2.71 ± 0.602 nmol/mL) were not statistically different from those determined in pre-delivery plasma (3.45 ± 0.530 nmol/mL). TBARS production was measured in vitro in the both incubated plasma (30 min, 37°C) with and without the added LPX activator (125 μM L-ascorbate plus 5 μM FeSO4). A difference in the TBARS formation was found only in the post-delivery plasma, as a result of approximately twice higher (marginally significant) TBARS formation in the incubated plasma without the added LPX activator comparing with the actual TBARS levels in this plasma. These results suggest that changes in maternal tissues in the process of labour could create suitable conditions for activation of LPX in maternal plasma. On the other hand, all other analysed biochemical parameters (iron, total iron-binding capacity, uric acid, proteins, magnesium, calcium, phosphate, glucose, potassium, sodium, chlorides, alanine aminotransferase, aspartate aminotransferase, γ-glutamyltransferase, creatine kinase, lactate dehydrogenase, α-hydroxybutyrate dehydrogenase, α-amylase, alkaline phosphatase, acid phosphatase in the post-delivery plasma were not different from those analysed in the pre-delivery plasma.  相似文献   
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93.
The role of the adenosine A3 receptor in hematopoiesis was studied using adenosine A3 receptor knockout (A3AR KO) mice. Hematological parameters of peripheral blood and femoral bone marrow of irradiated and untreated A3AR KO mice and their wild-type (WT) counterparts were investigated. Irradiation of the mice served as a defined hematopoiesis-damaging means enabling us to evaluate contingent differences in the pattern of experimentally induced hematopoietic suppression between the A3AR KO mice and WT mice. Defects were observed in the counts and/or functional parameters of blood cells in the A3AR KO mice. These defects include statistically significantly lower values of blood neutrophil and monocyte counts, as well as those of mean erythrocyte volume, mean erythrocyte hemoglobin, blood platelet counts, mean platelet volume, and plateletcrit, and can be considered to bear evidence of the lack of a positive role played by the adenosine A3 receptor in the hematopoietic system. Statistically significantly increased values of the bone marrow parameters studied in A3AR KO mice (femoral bone marrow cellularity, granulocyte/macrophage progenitor cells, and erythrocyte progenitor cells) can probably be explained by compensatory mechanisms attempting to offset the disorders in the function of blood elements in these mice. The pattern of the radiation-induced hematopoietic suppression was very similar in A3AR KO mice and their WT counterparts.  相似文献   
94.
NPY is present in the retina of different species but its role is not elucidated yet. In this work, using different rat retina in vitro models (whole retina, retinal cells in culture, microglial cell cultures, rat Müller cell line and retina endothelial cell line), we demonstrated that NPY staining is present in the retina in different cell types: neurons, macroglial, microglial and endothelial cells. Retinal cells in culture express NPY Y(1), Y(2), Y(4) and Y(5) receptors. Retina endothelial cells express all NPY receptors except NPY Y(5) receptor. Moreover, NPY is released from retinal cells in culture upon depolarization. In this study we showed for the first time that NPY is present in rat retina microglial cells and also in rat Müller cells. These in vitro models may open new perspectives to study the physiology and the potential pathophysiological role of NPY in the retina.  相似文献   
95.
MingCheng Luo  Kavitha Madishetty  Jan T. Svensson  Matthew J. Moscou  Steve Wanamaker  Tao Jiang  Andris Kleinhofs  Gary J. Muehlbauer  Roger P. Wise  Nils Stein  Yaqin Ma  Edmundo Rodriguez  Dave Kudrna  Prasanna R. Bhat  Shiaoman Chao  Pascal Condamine  Shane Heinen  Josh Resnik  Rod Wing  Heather N. Witt  Matthew Alpert  Marco Beccuti  Serdar Bozdag  Francesca Cordero  Hamid Mirebrahim  Rachid Ounit  Yonghui Wu  Frank You  Jie Zheng  Hana Simková  Jaroslav Dolezel  Jane Grimwood  Jeremy Schmutz  Denisa Duma  Lothar Altschmied  Tom Blake  Phil Bregitzer  Laurel Cooper  Muharrem Dilbirligi  Anders Falk  Leila Feiz  Andreas Graner  Perry Gustafson  Patrick M. Hayes  Peggy Lemaux  Jafar Mammadov  Timothy J. Close 《The Plant journal : for cell and molecular biology》2015,84(1):216-227
Barley (Hordeum vulgare L.) possesses a large and highly repetitive genome of 5.1 Gb that has hindered the development of a complete sequence. In 2012, the International Barley Sequencing Consortium released a resource integrating whole‐genome shotgun sequences with a physical and genetic framework. However, because only 6278 bacterial artificial chromosome (BACs) in the physical map were sequenced, fine structure was limited. To gain access to the gene‐containing portion of the barley genome at high resolution, we identified and sequenced 15 622 BACs representing the minimal tiling path of 72 052 physical‐mapped gene‐bearing BACs. This generated ~1.7 Gb of genomic sequence containing an estimated 2/3 of all Morex barley genes. Exploration of these sequenced BACs revealed that although distal ends of chromosomes contain most of the gene‐enriched BACs and are characterized by high recombination rates, there are also gene‐dense regions with suppressed recombination. We made use of published map‐anchored sequence data from Aegilops tauschii to develop a synteny viewer between barley and the ancestor of the wheat D‐genome. Except for some notable inversions, there is a high level of collinearity between the two species. The software HarvEST:Barley provides facile access to BAC sequences and their annotations, along with the barley–Ae. tauschii synteny viewer. These BAC sequences constitute a resource to improve the efficiency of marker development, map‐based cloning, and comparative genomics in barley and related crops. Additional knowledge about regions of the barley genome that are gene‐dense but low recombination is particularly relevant.  相似文献   
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97.
Dendritic cells (DCs) in the rheumatoid arthritis (RA) joint mediate the immunopathological process and act as a potent antigen presenting cell. We compared the expression of co-stimulatory and adhesion molecules on DCs in RA patients versus controls with traumatic joint lesions and evalulated the correlation between the immunophenotypical presentation of DCs and the clinical status of the disease. Samples of peripheral venous blood, synovial fluid (SF) and synovial tissue (ST) were obtained from 10 patients with RA at the time of hip or knee replacement and from 9 control patients with knee arthroscopy for traumatic lesions. Clinical status was appreciated using the DAS28 score. Blood, SF and dissociated ST cell populations were separated by centrifugation and analyzed by flow cytometry. Cells phenotypes were identified using three-color flow cytometry analysis for the following receptors HLA-DR, CD80, CD83, CD86, CD11c, CD18, CD54, CD58, CD3, CD4, CD8, CD19, CD20, CD14, CD16, CD56. HLA-DR molecules, co-stimulatory receptors CD80, CD86, CD83 and adhesion molecules CD18, CD11c, CD54, CD58, were analyzed by two-color immunofluorescence microscopy on ST serial sections. In patients with active RA (DAS28>5.1) we found a highly differentiated subpopulation of DCs in the ST and SF that expressed an activated phenotype (HLA-DR, CD86+, CD80+, CD83+, CD11c+, CD54+, CD58+). No differences were found between circulating DCs from RA patients and control patients. Our data suggest an interrelationship between clinical outcome and the immunophenotypical presentation of DCs. Clinical active RA (DAS28>5.1) is associated with high incidence of activated DCs population in the ST and SF as demonstrated by expression of adhesion and co-stimulatory molecules.  相似文献   
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99.
Carboxylated latex beads coated with fibronectin bind to the surfaces of NIL8 hamster cells. Similar beads coated with bovine serum albumin, gelatin or normal rabbit immunoglobulin do not bind to the cells, whereas beads coated with polylysine or rabbit anti-hamster immunoglobulin bind, as do fibronectin-coated beads. Surface-bound beads are endocytosed by the cells. This endocytosis is inhibited by N-ethyl maleimide or low temperatures. The endocytosed beads form arrays aligned with the microfilament bundles inside the cells and after extended incubations (18–24 h) become concentrated in the perinuclear region. These results suggest that, after phagocytosis of large particles, the endocytic vesicles align with microfilament bundles, as previously reported for coated pits involved in receptor-mediated endocytosis. The system described here offers possibilities for the analysis of membrane and transmembrane interactions involved in cell-substratum binding and phagocytosis.  相似文献   
100.
Apart from prevention using vaccinations, the management options for COVID-19 remain limited. In retrospective cohort studies, use of famotidine, a specific oral H2 receptor antagonist (antihistamine), has been associated with reduced risk of intubation and death in patients hospitalized with COVID-19. In a case series, nonhospitalized patients with COVID-19 experienced rapid symptom resolution after taking famotidine, but the molecular basis of these observations remains elusive. Here we show using biochemical, cellular, and functional assays that famotidine has no effect on viral replication or viral protease activity. However, famotidine can affect histamine-induced signaling processes in infected Caco2 cells. Specifically, famotidine treatment inhibits histamine-induced expression of Toll-like receptor 3 (TLR3) in SARS-CoV-2 infected cells and can reduce TLR3-dependent signaling processes that culminate in activation of IRF3 and the NF-κB pathway, subsequently controlling antiviral and inflammatory responses. SARS-CoV-2-infected cells treated with famotidine demonstrate reduced expression levels of the inflammatory mediators CCL-2 and IL6, drivers of the cytokine release syndrome that precipitates poor outcome for patients with COVID-19. Given that pharmacokinetic studies indicate that famotidine can reach concentrations in blood that suffice to antagonize histamine H2 receptors expressed in mast cells, neutrophils, and eosinophils, these observations explain how famotidine may contribute to the reduced histamine-induced inflammation and cytokine release, thereby improving the outcome for patients with COVID-19.  相似文献   
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