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1.
Rhinovirus antisera have been prepared for rhinoviruses (RV) 7,9,26,32,67 and 87 in guinea pigs and in degus. Titers achieved were either similar in the 2 animals (RV7) somewhat higher in the degu (RV9 and RV32) or clearly higher in the degu (RV26, RV67 and RV87). Specificity of the antisera was similar in both animals. In special instances where it is difficult to prepare high-titered rhinovirus antisera in the guinea pig, the degu offers an attractive alternative source.  相似文献   

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3.
Rhinoviruses (RVs) are the primary cause of upper respiratory tract infections, generally known as the common cold. Moreover, RV infections can trigger severe exacerbations of asthma and chronic obstructive pulmonary disease (COPD). We expressed the 4 major RV capsid proteins, VP1-VP4, in Escherichia coli and used these proteins as well as recombinant and synthetic VP1 fragments to study and map antibody responses in RV-infected humans. VP1, which on infection binds to ICAM 1, was identified as a major target for the memory immune response, residing in the IgG1 subclass and IgA class. Interestingly, this response was mainly directed against an N-terminal 20 mer peptide in VP1, P1a, which becomes exposed on intact RV only when it docks to its receptor ICAM 1. Molecular modeling using the 3-dimensional RV capsid structures revealed that P1a was localized inside the capsid and outside the areas involved in receptor binding or RV neutralization. Our results suggest misdirection of antibody responses against a nonprotective epitope as a mechanism how RV escapes immunity and causes recurrent infections. Based on these findings, it may be possible to design vaccines against RV infections and RV-induced respiratory diseases.  相似文献   

4.
Because of its complex geometry, assessment of right ventricular (RV) function is more difficult than it is for the left ventricle (LV). Because gene-targeted mouse models of cardiomyopathy may involve remodeling of the right heart, the purpose of this study was to develop high-resolution functional magnetic resonance imaging (MRI) for in vivo quantification of RV volumes and global function in mice. Thirty-three mice of various age were studied under isoflurane anesthesia by electrocardiogram-triggered cine-MRI at 7 T. MRI revealed close correlations between RV and LV stroke volume and cardiac output (r = 0.97, P < 0.0001 each). Consistent with human physiology, murine RV end-diastolic and end-systolic volumes were significantly higher compared with LV volumes (P < 0.05 each). MRI in mice with LV heart failure due to myocardial infarction revealed significant structural and functional changes of the RV, indicating RV dysfunction. Hence, MRI allows for the quantification of RV volumes and global systolic function with high accuracy and bears the potential to evaluate mechanisms of RV remodeling in mouse models of heart failure.  相似文献   

5.
Rotavirus (RV) diarrhoea causes huge number deaths in children less than 5 years of age. In spite of available vaccines, it has been difficult to combat RV due to large number of antigenically distinct genotypes, high mutation rates, generation of reassortant viruses due to segmented genome. RV is an eukaryotic virus which utilizes host cell machinery for its propagation. Since RV only encodes 12 proteins, post-translational modification (PTM) is important mechanism for modification, which consequently alters their function. A single protein exhibiting different functions in different locations or in different subcellular sites, are known to be 'moonlighting'. So there is a possibility that viral proteins moonlight in separate location and in different time to exhibit diverse cellular effects. Based on the primary sequence, the putative behaviour of proteins in cellular environment can be predicted, which helps to classify them into different functional families with high reliability score. In this study, sites for phosphorylation, glycosylation and SUMOylation of the six RV structural proteins (VP1, VP2, VP3, VP4, VP6 & VP7) & five non-structural proteins (NSP1, NSP2,NSP3,NSP4 & NSP5) and the functional families were predicted. As NSP6 is a very small protein and not required for virus growth & replication, it was not included in the study. Classification of RV proteins revealed multiple putative functions of each structural protein and varied number of PTM sites, indicating that RV proteins may also moonlight depending on requirements during viral life cycle. Targeting the crucial PTM sites on RV structural proteins may have implications in developing future anti-rotaviral strategies.  相似文献   

6.
BACKGROUND: In utero rubella virus (RV) infection of a fetus can result in birth defects that are often collectively referred to as congenital rubella syndrome (CRS). In extreme cases, fetal death can occur. In spite of the availability of a safe and effective vaccine against rubella, recent worldwide estimates are that more than 100,000 infants are born with CRS annually. RECENT PROGRESS: Recently, several significant findings in the field of cell biology, as well as in the RV replication and virus-cell interactions, have originated from the authors' laboratory, and other researchers have provided insights into RV teratogenesis. It has been shown that 1) an RV protein induces cell-cycle arrest by generating a subpopulation of tetraploid nuclei (i.e., 4N DNA) cells, perhaps representative of the tetraploid state following S phase in the cell cycle, due to its interaction with citron-K kinase (CK); 2) RV infection induces apoptosis in cell culture, and 3) CK functional perturbations lead to tetraploidy, followed by apoptosis, in specific cell types. CONCLUSIONS: Based on several similarities between known RV-associated fetal and cellular manifestations and CK deficiency-associated phenotypes, it is reasonable to postulate that P90-CK interaction in RV-infected cells interferes with CK function and induces cell-cycle arrest following S phase in a subpopulation, perhaps representative of tetraploid stage, which could lead to subsequent apoptosis in RV infection. Taking all these observations to the fetal organogenesis level, it is plausible that P90-CK interaction could perhaps be one of the initial steps in RV infection-induced apoptosis-associated fetal birth defects in utero.  相似文献   

7.
We used a live attenuated murine cytomegalovirus (MCMV) mutant to analyze mechanisms of vaccination against acute and latent CMV infection. We selected MCMV mutant RV7 as a vaccine candidate since this virus grows well in tissue culture but is profoundly attenuated for growth in normal and severe combined immunodeficient (SCID) mice (V. J. Cavanaugh et al., J. Virol. 70:1365–1374, 1996). BALB/c mice were immunized twice (0 and 14 days) subcutaneously (s.c.) with tissue culture-passaged RV7 and then challenged with salivary gland-passaged wild-type MCMV (sgMCMV) intraperitoneally (i.p.) on day 28. RV7 vaccination protected mice against challenge with 105 PFU of sgMCMV, a dose that killed 100% of mock-vaccinated mice. RV7 vaccination reduced MCMV replication 100- to 500-fold in the spleen between 1 and 8 days after challenge. We used the capacity to control replication of MCMV in the spleen 4 days after challenge as a surrogate for protection. Protection was antigen specific and required both live RV7 and antigen-specific lymphocytes. Interestingly, RV7 was effective when administered s.c., i.p., perorally, intranasally, and intragastrically, demonstrating that attenuated CMV applied to mucosal surfaces can elicit protection against parenteral virus challenge. B cells and immunoglobulin G were not essential for RV7-induced immunity since B-cell-deficient mice were effectively vaccinated by RV7. CD8 T cells, but not CD4 T cells, were critical for RV7-induced protection. Depletion of CD8 T cells by passive transfer of monoclonal anti-CD8 (but not anti-CD4) antibody abrogated RV7-mediated protection, and RV7 vaccination was less efficient in CD8 T-cell-deficient mice with a targeted mutation in the β2-microglobulin gene. Although gamma interferon is important for innate resistance to MCMV, it was not essential for RV7 vaccination since gamma interferon receptor-deficient mice were protected by RV7 vaccination. Establishment of and/or reactivation from latency by sgMCMV was decreased by RV7 vaccination, as measured by diminished reactivation of MCMV from splenic explants. We found no evidence for establishment of splenic latency by RV7 after s.c. vaccination. We conclude that RV7 administered through both systemic and mucosal routes is an effective vaccine against MCMV infection. It may be possible to design human CMV vaccines with similar properties.  相似文献   

8.
狂犬病毒aG株糖蛋白在pET原核系统中的表达及纯化   总被引:6,自引:0,他引:6  
在狂犬病的临床诊断和基础研究中都迫切需要大量纯度高且价廉的狂犬病毒糖蛋白抗原。本文应用带有His6尾的pET原核表达系统对狂犬病毒(RV)aG株的糖蛋白(GP)进行表达和纯化。构建的融合表达载体pET-aG1和pET-aG2(-57bp)分别含有RVaG株GP基因的全序列及删除了为GP信号肽编码的58个碱基的序列。用SDS 聚丙烯酰胺凝胶电泳、免疫印迹、间接ELISA检测都证明表达产物为RVGP,且位于菌体中的包涵体内。经固定化金属螯合层析(IMAC)提纯,pET-aG1表达产物有较高的特异性和纯度,可用作测定RVGP抗体的免疫诊断试剂。  相似文献   

9.
To examine the effects of glucocorticoid on rhinovirus (RV) infection, primary cultures of human tracheal epithelial cells were infected with either RV2 or RV14. Viral infection was confirmed by demonstrating that viral RNA in infected cells and viral titers of supernatants and lysates from infected cells increased with time. RV14 infection upregulated the expression of mRNA and protein of intercellular adhesion molecule-1 (ICAM-1), the major RV receptor, on epithelial cells, and it increased the production of interleukin (IL)-1beta, IL-6, IL-8, and tumor necrosis factor-alpha in supernatants. Dexamethasone reduced the viral titers of supernatants and cell lysates, viral RNA of infected cells, and susceptibility of RV14 infection in association with inhibition of cytokine production and ICAM-1 induction. In contrast to RV14 infection, dexamethasone did not alter RV2 infection, a minor group of RVs. These results suggest that dexamethasone may inhibit RV14 infection by reducing the surface expression of ICAM-1 in cultured human tracheal epithelial cells. Glucocorticoid may modulate airway inflammation via reducing the production of proinflammatory cytokines and ICAM-1 induced by rhinovirus infection.  相似文献   

10.
Wave speed (c) must be known to separate forward- and backward-going waves during wave-intensity analysis, which measures the energy transported by the waves in the circulation. c is related to elastance; the present study was performed to measure right ventricular (RV) c during the cardiac cycle and to compare c with RV elastance. In 7 dogs, we measured right atrial, pulmonary arterial, pericardial and 2 RV pressures, and pulmonary arterial flow. A pulse generator was connected to the RV apex, and c was measured by determining the transit time between the 2 high-fidelity RV pressure transducers; the distance was measured roentgenographically. Eight sonomicrometry crystals were implanted in the RV endocardium to calculate RV volume and, thereby, elastance. RV c ranged from approximately 1 m/s during diastole to approximately 4 m/s during systole. Log-log plots of c vs. elastance were linear. These slopes represent the power relationships between c and elastance and ranged from 0.30 to 0.56; for the combined data, it was 0.31. Given knowledge of c, forward- and backward-going waves can be identified and their energy quantitated. In the canine RV, c is approximately proportional to 1/3 the power of elastance: log c = 0.31.log E - 2.05.  相似文献   

11.
The efficiency of isolation of salmonellas from 412 seagull intestines and 247 polluted water samples was compared using three formulations of Rappaport's medium (RV, RV-soya and R25). A modification of RV medium (RV-soya) was shown to be the most efficient of the three media and it was shown that the duration of incubation of this medium could be restricted to 24 h. Inoculation ratios were compared for RV and RV-soya and 1:100 was shown to be significantly better than 1:20. It is concluded that RV-soya is at least as efficient as the standard RV medium and its use can therefore be recommended.  相似文献   

12.
Next-generation sequencing has led to many complex-trait rare-variant (RV) association studies. Although single-variant association analysis can be performed, it is grossly underpowered. Therefore, researchers have developed many RV association tests that aggregate multiple variant sites across a genetic region (e.g., gene), and test for the association between the trait and the aggregated genotype. After these aggregate tests detect an association, it is only possible to estimate the average genetic effect for a group of RVs. As a result of the "winner’s curse," such an estimate can be biased. Although for common variants one can obtain unbiased estimates of genetic parameters by analyzing a replication sample, for RVs it is desirable to obtain unbiased genetic estimates for the study where the association is identified. This is because there can be substantial heterogeneity of RV sites and frequencies even among closely related populations. In order to obtain an unbiased estimate for aggregated RV analysis, we developed bootstrap-sample-split algorithms to reduce the bias of the winner’s curse. The unbiased estimates are greatly important for understanding the population-specific contribution of RVs to the heritability of complex traits. We also demonstrate both theoretically and via simulations that for aggregate RV analysis the genetic variance for a gene or region will always be underestimated, sometimes substantially, because of the presence of noncausal variants or because of the presence of causal variants with effects of different magnitudes or directions. Therefore, even if RVs play a major role in the complex-trait etiologies, a portion of the heritability will remain missing, and the contribution of RVs to the complex-trait etiologies will be underestimated.  相似文献   

13.
Protective immunization against rotavirus (RV) can be achieved with heterologous RV, i.e., virus isolated from another species, and with heterologous inner core VP2 and VP6 proteins assembled as virus-like particles (VLP). Although the antigenically conserved VP6 protein does not induce in vitro-neutralizing antibodies, it may, however, elicit immunoglobulins (Ig) involved in heterologous protection, as some IgA against VP6 prevent RV infection in a backpack mouse model. The protective role of Ig directed to the RV inner core proteins VP2 and VP6 was investigated in J-chain-deficient mice (J chain(-/-)), which have a defect in the polymeric Ig receptor (pIgR)-mediated transcytosis of IgA and IgM. J chain(-/-) mice and wild-type (WT) mice were intranasally vaccinated with bovine RV-derived VLP2/6 and then challenged with highly infectious murine ECw RV. Whereas WT mice were totally protected, immunized J chain(-/-) mice shed RV for several days. In addition, na?ve J chain(-/-) mice exhibited a 2-day delay in clearing RV compared with WT mice. The immunized J chain(-/-) mice displayed unaltered VLP2/6-specific B-cell numbers in spleen and in mesenteric nodes and similar levels of serum anti-VLP2/6 Ig, confirming that the adaptive B-cell response is preserved in J chain(-/-) mice. These results indicate that J-chain-mediated transcytosis of Ig participates in the clearance of RV and that epithelial pIgR-mediated transport of Ig is involved in the heterologous protection induced by VLP2/6.  相似文献   

14.
Summary The antimetastatic activity of orally administered polybacterial vaccines, Broncho-Vaxom (BV) and Respivax (RV) was examined in C57BL/6 mice, bearing implants of Lewis lung carcinoma (3LL) in the footpad. The oral administration of BV or RV for 10 consecutive days before or after surgery caused significant reduction of the number and volume of lung metastases. In addition, the therapeutic potential of BV and RV was examined in combination with chemotherapy to determine if there is additive activity. In animals bearing pulmonary micrometastases, treatment with a combination of cyclophosphamide at 50–150 mg/kg with BV or RV was found to be more effective than each of these treatments alone. In immune function studies it was established that the oral administration of BV and RV induced an increase in the number of cells, recovered by broncho-alveolar lavage, and alveolar macrophages were dominant in these cell populations. Furthermore, oral treatment of mice with these vaccines rendered their alveolar macrophages tumoricidal for syngeneic metastatic 3LL cells in vitro. These results show that pulmonary macrophages induced by oral administration of BV and RV played a key role in the inhibition of metastasis in 3LL-bearing mice.  相似文献   

15.
The left ventricle (LV) and right ventricle (RV) have differing hemodynamics and embryological origins, but it is unclear whether they are regulated differently. In particular, no previous studies have directly compared the LV versus RV myocardial inotropic responses to alpha(1)-adrenergic receptor (alpha(1)-AR) stimulation. We compared alpha(1)-AR inotropy of cardiac trabeculae from the LV versus RV of adult mouse hearts. As previously reported, for mouse RV trabeculae, alpha(1)-AR stimulation with phenylephrine (PE) caused a triphasic contractile response with overall negative inotropy. In marked contrast, LV trabeculae had an overall positive inotropic response to PE. Stimulation of a single subtype (alpha(1A)-AR) with A-61603 also mediated contrasting LV/RV inotropy, suggesting differential activation of multiple alpha(1)-AR-subtypes was not involved. Contrasting LV/RV alpha(1)-AR inotropy was not abolished by inhibiting protein kinase C, suggesting differential activation of PKC isoforms was not involved. However, contrasting LV/RV alpha(1)-AR inotropic responses did involve different effects on myofilament Ca(2+) sensitivity: submaximal force of skinned trabeculae was increased by PE pretreatment for LV but was decreased by PE for RV. For LV myocardium, alpha(1)-AR-induced net positive inotropy was abolished by the myosin light chain kinase inhibitor ML-9. This study suggests that LV and RV myocardium have fundamentally different inotropic responses to alpha(1)-AR stimulation, involving different effects on myofilament function and myosin light chain phosphorylation.  相似文献   

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Although the neural cell adhesion molecule (NCAM) -140 and -180 have been shown to serve as a receptor for rabies virus (RV), it was not known whether the other major isoform of NCAM, GPI-anchored NCAM-120 functions as RV receptor. In this study, we have established HEp-2 cells stably expressing NCAM-120 or NCAM-140, and their susceptibilities to RV infection were compared. The results demonstrated that NCAM-120 served as virus attachment protein; however, the cells expressing NCAM-120 did not support efficient RV replication. Furthermore, the level of IFN-ss mRNA was apparently elevated in NCAM-120 expressing cells but not in NCAM-140 expressing cells, suggesting that GPI-anchored NCAM-120 suppressed RV replication via induction of IFN-ss even though NCAM-120 was able to promote virus penetration into the cells.  相似文献   

18.
Resveratrol (3,5,4'-trihydroxy-trans-stilbene; RV), a dietary constituent found in grapes and wine, exerts a wide variety of pharmacological activities. Because the grape skins are not fermented in the production process of white wines, only red wines contain considerable amounts of this compound. RV is metabolized into sulfated and glucuronidated forms within approximately 15min of entering the bloodstream, and moderate consumption of red wine results in serum levels of RV that barely reach the micromolar concentrations. In contrast, its metabolites, which may be the active principle, circulate in serum for up to 9h. RV has been identified as an effective candidate for cancer chemoprevention due its ability to block each step in the carcinogenesis process by inhibiting several molecular targets such as kinases, cyclooxygenases, ribonucleotide reductase, and DNA polymerases. In addition, RV protects the cardiovascular system by a large number of mechanisms, including defense against ischemic-reperfusion injury, promotion of vasorelaxation, protection and maintenance of intact endothelium, anti-atherosclerotic properties, inhibition of low-density lipoprotein oxidation, and suppression of platelet aggregation, thereby strongly supporting its role in the prevention of coronary disease. Promising data within the use of RV have also been obtained regarding progressive neurodegenerative maladies such as Alzheimer's, Huntington's, and Parkinson's diseases. Because neurotoxicity is often related to mitochondrial dysfunction and may be ameliorated through the inclusion of metabolic modifiers and/or antioxidants, RV may provide an alternative (and early) intervention approach that could prevent further damage. RV induces a multitude of effects that depend on the cell type (e.g., NF-kappaB modulation in cancer cells vs. neural cells), cellular condition (normal, stressed, or malignant), and concentration (proliferative vs. growth arrest), and it can have opposing activities. RV affects whole pathways and sets of intracellular events rather than a single enzyme and, therefore, may be an effective therapy to restore homoestasis. Nonetheless, the question of whether RV or its metabolites can accumulate to bioactive levels in target organs remains to be addressed.  相似文献   

19.
Volume expansion and inotropic stimulation are used clinically to augment cardiac output during acute right ventricular (RV) pressure overload. We previously showed that a brief period of RV pressure overload causes RV free wall dysfunction that persists after normal loading conditions have been restored. However, the impact of volume expansion and inotropic stimulation on the severity of RV dysfunction after acute pressure overload is unknown. We hypothesized that the severity of RV dysfunction after RV pressure overload would be related to the level of RV free wall systolic stress during RV pressure overload, rather than to the specific interventions used to augment RV function. Chloralose-anesthetized, open-chest pigs were subjected to 1 h of RV pressure overload caused by pulmonary artery constriction, followed by 1 h of recovery after release of pulmonary artery constriction. A wide range of RV free wall systolic stress during RV pressure overload was achieved by either closing or opening the pericardium (to simulate volume expansion) and by administering or not administering dobutamine. The severity of RV free wall dysfunction 1 h after RV pressure overload was strongly and directly correlated with the values of two hemodynamic variables during RV pressure overload: RV free wall area at peak RV systolic pressure (determined by sonomicrometry) and peak RV systolic pressure, two of the major determinants of peak RV free wall systolic stress. Opening or closing the pericardium, and using or not using dobutamine during RV pressure overload, had no independent effects on the severity of RV dysfunction. The findings suggest that the goal of therapeutic intervention during RV pressure overload should be to achieve the required augmentation of cardiac output with the smallest possible increase in RV free wall systolic stress.  相似文献   

20.
Right ventricular (RV) mid-septal pacing should have fewer negative effects on left ventricular function compared to apical pacing. However, targeting the mid-septum may be technically challenging since it is usually done with two-dimensional fluoroscopy. The rotation of the heart and various shapes of the RV make it difficult to assess, whether the lead is really anchored in the septum. Many leads, apparently anchored in the septum, are in fact anchored in the anterior wall or anteroseptal groove, and some can get anchored in close proximity to the left anterior descending artery (LAD). We report three cases from our series of 51 patients, in whom the RV lead thought to be implanted in the mid-septum was in fact anchored in close proximity of LAD when assessed using computed tomography.  相似文献   

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