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Zika virus (ZIKV) recently outbreaking from 2015 to 2016 over Americas has attracted a global health concern. As a member of family of Flaviviridae, Zika virus a positive-sense single-stranded RNA virus is highly likely associated with birth defects (primary microcephaly) and neurological complications. However, computer simulation method is widely used to study spread of Zika virus at macroscale level and related-structures and vaccines of Zika virus at atomic level, which also provides insights into Zika virus. Here the current advancements were reviewed and future developments were discussed.

Objective The BXSB.Yaa mouse strain is a model of systemic lupus erythematosus that is dependent on duplication of the Toll-like receptor 7 gene. The objective of this study was to systematically describe the amplified autoimmune phenotype observed when the soluble plasma protein β2-glycoprotein I (β2GPI) gene was deleted in male BXSB.Yaa mice. Methods We generated BXSB.Yaa and NZW mouse strains in which the β2GPI gene had been knocked out by backcrossing the wild-type strains with C57BL/6 β2GPI−/− mice for 10 generations. Sex- and age-matched mice of the various strains were housed under identical conditions and were killed at fixed time intervals. Serum and tissue specimens were collected at various time points. Lupus-associated autoantibodies, inflammatory cytokines, and the type I interferon (IFN) gene signature were measured. Flow cytometric analyses of lymphocyte populations were performed. The severity of glomerulonephritis was graded by 2 independent renal histopathologists. Results Male BXSB.Yaa β2GPI−/− mice developed significant lymphadenopathy and splenomegaly compared with age-matched controls. Male BXSB.Yaa β2GPI−/− mice also had significantly higher levels of autoantibodies, increased levels of inflammatory cytokines including tumor necrosis factor α, interleukin-6, and BAFF, and more severe glomerulonephritis. The type I IFN gene signature in male BXSB.Yaa β2GPI−/− mice was significantly higher than that in control mice. Male BXSB.Yaa β2GPI−/− mice also had marked dysregulation of various B cell and T cell populations in the spleens and lymph nodes and a disturbance in apoptotic cell clearance. Conclusion Deletion of β2GPI accelerates and potentiates the autoimmune phenotype in male BXSB.Yaa mice.

β2-Glycoprotein I (β2GPI) is an evolutionary conserved, abundant circulating protein. Although its function remains uncertain, accumulated evidence points toward interactions with endothelial cells and components of the coagulation system, suggesting a regulatory role in vascular biology. Our group has shown that thioredoxin 1 (TRX-1) generates free thiols in β2GPI, a process that may have a regulatory role in platelet adhesion. This report extends these studies and shows for the first time evidence of β2GPI with free thiols in vivo in both multiple human and murine serum samples. To explore how the vascular surface may modulate the redox status of β2GPI, unstimulated human endothelial cells and EAhy926 cells are shown to be capable of amplifying the effect of free thiol generation within β2GPI. Multiple oxidoreductase enzymes, such as endoplasmic reticulum protein 46 (ERp 46) and TRX-1 reductase, in addition to protein disulfide isomerase are secreted on the surface of endothelial cells. Furthermore, one or more of these generated free thiols within β2GPI are also shown to be nitrosylated. Finally, the functional significance of these findings is explored, by showing that free thiol–containing β2GPI has a powerful effect in protecting endothelial cells and EAhy926 cells from oxidative stress–induced cell death.

Background: beta(2)-Glycoprotein I (beta(2)GPI) is an abundant plasma protein that is closely linked to blood clotting, as it interacts with various protein and cellular components of the coagulation system. However, the role of beta(2)GPI in thrombus formation is unknown. We have recently shown that beta(2)GPI is susceptible to reduction by the thiol oxidoreductases thioredoxin-1 and protein disulfide isomerase, and that reduction of beta(2)GPI can take place on the platelet surface. Methods: beta(2)GPI, reduced by thioredoxin-1, was labeled with the selective sulfhydryl probe Na-(3-maleimidylpropionyl)biocytin and subjected to mass spectrometry to identify the specific cysteines involved in the thiol exchange reaction. Binding assays were used to examine the affinity of reduced beta(2)GPI for von Willebrand factor (VWF) and the effect of reduced beta 2GPI on glycoprotein (GP)Ib alpha binding to VWF. Platelet adhesion to ristocetin-activated VWF was studied in the presence of reduced beta(2)GPI. Results: We demonstrate that the Cys288-Cys326 disulfide in domain V of beta(2)GPI is the predominant disulfide reduced by thioredoxin-1. Reduced beta(2)GPI in vitro displays increased binding to VWF that is dependent on disulfide bond formation. beta(2)GPI reduced by thioredoxin-1, in comparison with non-reduced beta(2)GPI, leads to increased binding of GPIb alpha to VWF and increased platelet adhesion to activated VWF. Conclusions: Given the importance of thiol oxidoreductases in thrombus formation, we provide preliminary evidence that the thiol-dependent interaction of beta(2)GPI with VWF may contribute to the redox regulation of platelet adhesion.

Ras guanine nucleotide-releasing protein 4 (RasGRP4) is a mast cell (MC)-restricted guanine nucleotide exchange factor and diacylglycerol (DAG)/phorbol ester receptor. An RasGRP4-defective variant of the human MC line HMC-1 was used to create stable clones expressing green fluorescent protein-labeled RasGRP4 for monitoring the movement of this protein inside MCs after exposure to phorbol 12-myristate 13-acetate (PMA), and for evaluating the protein's ability to control gene expression. RasGRP4 resided primarily in the cytosol. After exposure to PMA, RasGRP4 quickly translocated to the inner leaflet of the cell's plasma membrane. 15-30 min later, this signaling protein translocated from the plasma membrane to other intracellular sites. The translocation of RasGRP4 from the cytosol to its varied membrane compartments was found to be highly dependent on Phe(548) in the protein's C1 DAG/PMA-binding domain. Extracellular signal-regulated kinases 1 and 2 were activated during this translocation process, and c-kit/CD117 was lost from the cell's surface. Transcript-profiling approaches revealed that RasGRP4 profoundly regulated the expression of hundreds of genes in HMC-1 cells. For example, the expression of the transcript that encodes the interleukin (IL) 13 receptor IL-13Ralpha2 increased 61- to 860-fold in RasGRP4-expressing HMC-1 cells. A marked increase in IL-13Ralpha2 protein levels also was found. The accumulated data suggest RasGRP4 translocates to varied intracellular compartments via its DAG/PMA-binding domain to regulate signaling pathways that control gene and protein expression in MCs, including the cell's ability to respond to IL-13.

Human mast cells (MCs) and basophils play a key role in the pathogenesis of allergic disorders, not only by producing inflammatory and fibrogenic mediators, but also by directly and indirectly secreting various cytokines and chemokines. Although mast cells and basophils have differences in many properties, recent evidence suggests that human MCs and basophils may be derived from a common progenitor, and their contents and phenotypes may be reversibly altered in a variety of allergic disorders. The study of FcetaRI signalling of mast cell and basophils offers new opportunities for therapeutic interventions based on the specific inhibition of the earliest events in allergic diseases. This article reviews the origin, differentiation, morphology and phenotypic properties of MCs and basophils, focussing particularly on the possible pathogenic role of MCs and basophils in allergy and biochemical targets for therapeutic interventions in allergic diseases.

The BXSB.Yaa mouse strain is a model of systemic lupus erythematosus that is dependent on duplication of the Toll-like receptor 7 gene. The objective of this study was to systematically describe the amplified autoimmune phenotype observed when the soluble plasma protein β2 -glycoprotein I (β2 GPI) gene was deleted in male BXSB.Yaa mice.We generated BXSB.Yaa and NZW mouse strains in which the β2 GPI gene had been knocked out by backcrossing the wild-type strains with C57BL/6 β2 GPI(-/-) mice for 10 generations. Sex- and age-matched mice of the various strains were housed under identical conditions and were killed at fixed time intervals. Serum and tissue specimens were collected at various time points. Lupus-associated autoantibodies, inflammatory cytokines, and the type I interferon (IFN) gene signature were measured. Flow cytometric analyses of lymphocyte populations were performed. The severity of glomerulonephritis was graded by 2 independent renal histopathologists.Male BXSB.Yaa β2 GPI(-/-) mice developed significant lymphadenopathy and splenomegaly compared with age-matched controls. Male BXSB.Yaa β2 GPI(-/-) mice also had significantly higher levels of autoantibodies, increased levels of inflammatory cytokines including tumor necrosis factor α, interleukin-6, and BAFF, and more severe glomerulonephritis. The type I IFN gene signature in male BXSB.Yaa β2 GPI(-/-) mice was significantly higher than that in control mice. Male BXSB.Yaa β2 GPI(-/-) mice also had marked dysregulation of various B cell and T cell populations in the spleens and lymph nodes and a disturbance in apoptotic cell clearance.Deletion of β2 GPI accelerates and potentiates the autoimmune phenotype in male BXSB.Yaa mice.

To evaluate the performance of vaporized hydrogen peroxide (VHP) for the bio-decontamination of the high efficiency particulate air (HEPA) filter unit.Self-made or commercially available bioindicators were placed at designated locations in the HEPA filter unit under VHP fumigation. The spores on coupons were then extracted by 0.5 h submergence in eluent followed by 200- time violent knocks.Due to the presence of HEPA filter in the box, spore recovery from coupons placed at the bottom of the filter downstream was significantly higher than that from coupons placed at the other locations. The gap of decontamination efficiency between the top and the bottom of the filter downstream became narrower with the exposure time extended. The decontamination efficiency of the bottom of the filter downstream only improved gently with the injection rate of H2O2 increased and the decontamination efficiency decreased instead when the injection rate exceeded 2.5 g/min. The commercially available bioindicators were competent to indicate the disinfection efficiency of VHP for the HEPA filter unit.This assay developed can detect all 16 β-lactams demanded by the European Union (EU). The whole procedure takes only 45 min and can detect 42 samples and the standards with duplicate analysis.

Circulating osteocalcin, a marker of bone formation, is under strong genetic influence, and this effect is related to the genetic influence on bone density. To examine genetic influences on bone turnover further, other markers of bone formation (serum carboxyterminal propeptide of type I procollagen, PICP), bone resorption (serum pyridinoline cross-linked carboxyterminal telopeptide of type I collagen, ICTP), and nonosseous connective tissue synthesis (serum aminoterminal propeptide of type III procollagen, PIIINP) were studied in 82 female twin pairs: 42 monozygotic (MZ) and 40 dizygotic (DZ) twin pairs (mean age, MZ; 48.4 yr; DZ; 45.6 yr). The intraclass correlation coefficients of MZ twin pairs, rMZ, for serum PICP (0.78) and serum ICTP (0.68) were significantly greater than the corresponding rDZ (0.31 and 0.36, respectively), but a genetic effect on serum PIIINP was not demonstrable. Within DZ twin pair differences in serum PICP predicted differences in lumbar spine bone density (r = -0.37); higher serum PICP levels indicating the twin with the lower lumbar spine bone density. Also within pair differences in serum ICTP and PICP predicted differences in bone density at the lumbar spine independent of serum osteocalcin. These data indicate that both synthesis and degradation of type I collagen are genetically determined and that this phenomenon is related to the genetic regulation of bone density.

Bone density achieved in early adulthood is the major determinant of risk of osteoporotic fracture. Up to 60% of women suffer osteoporotic fractures as a result of low bone density, which is under strong genetic control acting through effects on bone turnover. Here we show that common allelic variants in the gene encoding the vitamin D receptor can be used to predict differences in bone density, accounting for up to 75% of the total genetic effect on bone density in healthy individuals. The genotype associated with lower bone density was overrepresented in postmenopausal women with bone densities more than 2 standard deviations below values in young normal women. The molecular mechanisms by which bone density is regulated by the vitamin D receptor gene are not certain, although allelic differences in the 3' untranslated region may alter messenger RNA levels. These findings could open new avenues to the development and targeting of prophylactic interventions. It follows that other pathophysiological processes considered to be subject to complex multifactorial genetic regulation may also be modulated by a single gene with pleiotropic transcriptional actions.

The antiphospholipid syndrome (APS) is an autoimmune condition characterized by vascular thrombosis of the arterial and/or venous systems as well as recurrent miscarriages (1). Beta-2-glycoprotein I (β2GPI) is the major autoantigen in APS (2). A number of studies have provided robust evidence that autoantibodies to β2GPI are a significant risk factor for arterial thrombosis in young adults (3, 4). In vivo and ex vivo studies by multiple groups have shown anti-β2GPI autoantibodies to be directly thrombogenic (5). At present it is not possible to stratify the risk for development of thrombosis in antiphospholipid antibody (aPL)–positive patients based on clinical features or use of currently available laboratory assays (6). The development of novel assays that could be used to stratify future thrombosis risk in patients with APS would hold immense clinical utility in informing the decision as to whether initiation of prophylactic therapy or intensification of therapy is warranted. Beta-2-glycoprotein I is an evolutionarily conserved 50-kd protein circulating in the blood in relative abundance (∼4 μM) (7). The physiologic role of β2GPI is pleiotropic, with functional studies implicating a role in processes relating to coagulation (8), angiogenesis (9), and clearance of apoptotic cells (10). The crystal structure of β2GPI, which has been ascertained based on the purified native protein, reveals that it does not possess free thiols (11, 12). We have recently shown, however, that in vivo β2GPI circulates in a free thiol form and that this free thiol form of β2GPI is involved in the protection of endothelial cells against oxidative stress–induced cell injury (13). Beta-2-glycoprotein I can also participate in redox thiol-exchange reactions by acting as a substrate for oxidoreductase enzymes such as thioredoxin 1 (14). However, the proportion of β2GPI circulating in the reduced state is unknown. Also unknown is whether the redox state of this autoantigen differs in patients with pathogenic anti-β2GPI antibodies and a history of thrombosis. In the present study we demonstrated that, in serum/plasma derived from healthy subjects, β2GPI exists in a reduced biochemical state as the dominant molecular phenotype. Detailed in vitro quantitative assays to assess the levels of total and reduced β2GPI were developed and used to screen >450 samples. Levels of both total and oxidized β2GPI were found to be elevated in patients with APS as compared to disease and healthy control groups. These findings have implications with respect to understanding the antigenic drive for pathogenic aPL, as well as the potential for development of assays for purposes of thrombosis risk stratification.

The close phylogenetic relationship between humans and non-human primates makes non-human primates an irreplaceable model for the study of human infectious diseases. In this study, we describe the development of a large-scale automatic multi-functional isolation chamber for use with medium-sized laboratory animals carrying infectious diseases. The isolation chamber, including the transfer chain, disinfection chain, negative air pressure isolation system, animal welfare system, and the automated system, is designed to meet all biological safety standards. To create an internal chamber environment that is completely isolated from the exterior, variable frequency drive blowers are used in the air-intake and air-exhaust system, precisely controlling the filtered air flow and providing an air-barrier protection. A double door transfer port is used to transfer material between the interior of the isolation chamber and the outside. A peracetic acid sterilizer and its associated pipeline allow for complete disinfection of the isolation chamber. All of the isolation chamber parameters can be automatically controlled by a programmable computerized menu, allowing for work with different animals in different-sized cages depending on the research project. The large-scale multi-functional isolation chamber provides a useful and safe system for working with infectious medium-sized laboratory animals in high-level bio-safety laboratories.

Objective Beta2-glycoprotein I (β2GPI) is an important autoantigen in the antiphospholipid syndrome (APS). In vitro studies suggest that it may have multifaceted physiologic functions, since it displays both anticoagulant and procoagulant properties. We have previously reported that β2GPI can directly bind thrombin, a key serine protease in the coagulation pathway. The present study was undertaken to examine the influence of β2GPI on thrombin inactivation by the serpin heparin cofactor II (HCII). The effect of anti-β2GPI antibodies was also examined. Methods HCII inactivation of thrombin was assessed using chromogenic and various platelet functional assays. The influence of intact and proteolytically cleaved β2GPI and anti-β2GPI antibodies was determined in these systems. Results β2GPI protected thrombin against inactivation by HCII/heparin. Cleavage of β2GPI at Lys317–Thr318 abrogated its protective effect. Patient polyclonal IgG and murine monoclonal anti-β2GPI antibodies potentiated the procoagulant influence of β2GPI in this system. Conclusion These novel findings suggest that β2GPI may regulate thrombin inactivation by HCII/heparin. The observation that anti-β2GPI antibodies potentiate the protective effect of β2GPI on thrombin in this system, thereby promoting a procoagulant response, may potentially delineate one of the pathophysiologic mechanisms contributing to the prothrombotic tendency in patients with APS.

To investigate the effects of high D-glucose on migration, proliferation, and angiogenesis of endothelial cells and to make sure whether PI3K and Akt signaling pathway plays an important role in the pathogenesis of diabetic vascular complications.Human umbilical vein endothelial cells (HUVECs) were cultured. D-glucose of the concentrations of 5 mmol/L, 15 mmol/L, and 30 mmol/L and mannitol of the concentrations of 5 mmol/L, 15 mmol/L, and 30 mmol/L were added in to the medium, the migration rate of the cells was measured by wound healing test and the cell proliferation was examined with CellTiter 96 AQ(ueous) One Solution cell proliferation assay. Matrigel was spread on 96-well plate, and culture of HUVECs with D-glucose and mannitol of different concentrations were added. Microscopic photography was used to calculate the total area of vascular bed, average vessel length, vessel number, branch points, so as to observe the angiogenesis. Immuno-precipitation was used to detect the expression of p85/PI3K. Western blotting was used to detect the protein expression of p85/PI3K, p-PI3K, GSK3beta (downstream kinase of Akt), p-Akt (Threonine308) and p-GSK3beta. LY294002, a PI3K inhibitor, of the concentrations of 0.1 micromol/L, 1 micromol/L, and 10 micromol/L was added into the culture fluid with 5 mmol/L D-glucose, then the endothelial cell migration, proliferation number, total area of blood bed, etc were observed.The migration rate of the 5 mmol/L D-glucose group was 100 +/- 23/microm2, and D-glucose dose-dependently decreased the migration rate, e.g. the migration rates of the 15 mmol/L and 30 mmol/L D-glucose groups were 77 +/- 18/microm2 and 46 +/- 18/microm2 respectively, both significantly lower than that of the 5 mmol/L D-glucose group (both P0.01). LY294002 of the concentrations of 0.1 micromol/L, 1 micromol/L, and 10 micromol/L dose-dependently decrease the endothelial cells migration rates to 68 +/- 16/microm2, 36 +/- 12/microm2, and 13 +/- 3/microm2 respectively (all P0.01) The cell proliferation rate of the 5 mmol/L, 15 mmol/L) and 30 mmol/L D-glucose groups were 59,128 +/- 7415/well, 33,144 +/- 9082/well, and 11,625 +/- 4196/well respectively, showing that D-glucose dose-dependently decreased the cell proliferation (all P0.01). LY294002 of the concentrations of 0.1 micromol/L, 1 micromol/L, and 10 micromol/L dose-dependently decrease the endothelial cell proliferation to 42,560 +/- 4213/well, 17,688 +/- 7198/well, and 5704 +/- 558/well respectively (all P0.01). 15 mmol/L and 30 mmol/L D-glucose decreased the numbers of total area of vascular bed, average tubule length, number of capillaries, and number of vessel branch pint formed on the Matrigel. LY294002 dose-dependently inhibited the angiogenesis (P0.05 or P0.01) 15 mmol/L and 30 mmol/L D-glucose dose-dependently inhibited the phosphorylation of p85/P13K and Akt (P0.05 and P0.01). However, D-glucose did not influence the protein expression of p85/PI3K and Akt. Mannitol did not influence the cell proliferation, angiogenesis, and the expression of p85/PI3K, phosphorylated p85/PI3K, Akt, phosphorylated Akt (Thr308), and phosphorylated GSK3beta.Hyperglycemia-impaired PI3K-Akt signaling may lead to migration, proliferation and angiogenesis dysfunction of endothelial cells in diabetes patients, which is likely to contribute to the pathogenesis of diabetic vascular complications.

Selective markers for human mast cells are of paramount importance for understanding their role in physiological and pathological processes. A mouse monoclonal antibody (MAb) designated 2C7, raised against in vitro-derived human mast cells, was used in immunoenzymatic analysis of sections from a variety of human organs. Double immuno-labeling with 2C7 and tryptase, chymase, Fc∊RIα, and c-kit was performed on cryostat tissue sections from skin, colon, uterus, breast, stomach, bladder, and lung. MAb 2C7 stained greater than 93% of the tryptase+ or chymase+ mast cells in all tissues examined. In addition, the majority of cells stained with the tryptase or chymase also stained for Fc∊RIα. However, there were a significant number of Fc∊RIα+ cells in all tissues studied that were tryptase− and/or chymase−. In contrast, MAb 2C7 in double immunoenzymatic staining co-localized with 93–96% of the Fc∊RIα+ cells in all tissues. Analysis for c-kit expression on the different tissues revealed that the majority of tryptase+ or chymase+ cells in skin, uterus, bladder, and lung stained with c-kit. However, only approximately 70-78% of tryptase+ cells in colon and stomach were c-kit+. These data suggest that MAb 2C7 appears to identify mature mast cells and a population of Fc∊RIα+, chymase−, and tryptase− cells in a variety of human tissues.

Objective. To establish the models of head, abdomen, and chest of supine human body respectively under vertical vibration. Method. The mechanical impedance of 12 healthy volunteers aged 24-56 was measured under vertical white noise stimulus in the frequency range of 2-35 Hz. To explain these findings, the model of head was proposed, the models of abdomen and chest were computed by way of an optimization procedure. Result. The models of abdomen and chest are three-degree-of-freedom and the head is rigid. Conclusion. The mechanical impedance of the supine human body is linear and sole. The established models of head, abdomen and chest of supine human body when subjected to vertical vibration are useful for calculating and evaluating the comfort of supine human body under whole-body vibration.

AIDS patients often contain HIV-1-infected mast cells (MCs)/basophils in their peripheral blood, and in vivo-differentiated MCs/basophils have been isolated from the blood of asthma patients that are HIV-1 susceptible ex vivo due to their surface expression of CD4 and varied chemokine receptors. Because IL-16 is a ligand for CD4 and/or an undefined CD4-associated protein, the ability of this multifunctional cytokine to regulate the development of human MCs/basophils from nongranulated progenitors residing in cord or peripheral blood was evaluated. After 3 wk of culture in the presence of c-kit ligand, IL-16 induced the progenitors residing in the blood of normal individuals to increase their expression of chymase and tryptase about 20-fold. As assessed immunohistochemically, >80% of these tryptase+ and/or chymase+ cells expressed CD4. The resulting cells responded to IL-16 in an in vitro chemotaxis assay, and this biologic response could be blocked by anti-IL-16 and anti-CD4 Abs as well as by a competitive peptide inhibitor corresponding to a sequence in the C-terminal domain of IL-16. The additional finding that IL-16 induces calcium mobilization in the HMC-1 cell line indicates that IL-16 acts directly on MCs and their committed progenitors. IL-16-treated MCs/basophils also are less susceptible to infection by an M/R5-tropic strain of HIV-1. Thus, IL-16 regulates MCs/basophils at a number of levels, including their vulnerability to retroviral infection.

Nature 367, 284-287 (1994) .... In order to expand our original observations of a relationship between bone density and vitamin D receptor (VDR) genotype and to examine other genes potentially involved in bone biology, we set out to recruit a larger set of identical and non-identical twins. On re-analysis of these newly collected and re-genotyped samples, we found reduced correlation of the VDR genotype with bone density in this larger sample of twin pairs.