100 research outputs found
Correlation between Epstein-Barr virus infection and disease activity of systemic lupus erythematosus: A cross-sectional study
Background:
Systemic lupus erythematosus (SLE) is an autoimmune disease for whose pathogenesis viral infections are important. The Epstein-Barr virus (EBV) is the main infectious etiological agent. This study aimed to quantitative evaluation of EBV in SLE patients.
Materials and Methods:
In this cross-sectional study, 40 patients with SLE diagnosed based on American College of Rheumatology criteria were selected using purposive sampling. All were included in the study after obtaining informed consent for participation. Whole blood samples were taken and buffy coat preparations were isolated to determine viral load using the real-time polymerase chain reaction method and assessment with the SLE disease activity index (SLE-DAI).
Results:
From a total of 40 patients, 37 cases (92.5%) were women. The EBV test was positive in 67.5% and mean viral load was 5396 ± 1891.9 copy/ml. Twenty of forty patients had active and 50% inactive disease, mean EBV viral loads being 6798 and 28.25 copy/ml, respectively (P-value = 0.003). In terms of the severity of disease activity, 17.5 % of female patients had mild to moderate activity, whilst 32.5% of them had severe activity, with respective viral loads of 5,803.3 and 29.73 copy/ml (P-value = 0.003).
Conclusion:
The Epstein-Barr viral load in SLE patients with active disease was found to be markedly higher than in inactive cases. Thus, EBV may have an important role in the pathogenesis and activity of SLE.
Keywords: Epstein-Barr virus, viral load, systemic lupus erythematosus, real-time PCR, human, infectio
Frequency of HLA-B27 in Patients With Conductive System Disturbance and Implanted Permanent Pacemaker in Iran
Introduction: HLA-B27 is considered as one of the causes of heart conductive disorders. We studied the frequency of HLA-B27 among Iranian patients who had undergone permanent pacemaker implantation.Methods: This descriptive and analytical study was performed among patients who underwent permanent pacemaker implantation. The questionnaire contains demographic data, underling diseases, and history of heart disease or heart surgery. The type of conductive heart disorder was mentioned there, too. We determined the regurgitation of aorta valve and its severity. Finally, HLA-B27 was accessed. All the data was entered in SPSS software and analyzed.Results: From a total of 103 patients entered in this study, only 6 (5.8%) were HLAB-27 positive. The disturbance of conductive heart disorders based on the HLA-B27 positive or negative patients was not statistically different. Patients with HLA-B27 mostly had regurgitation of the aorta valve.Conclusions: We concluded that the frequency of positive HLA-B27 genotype in patients with permanent pacemakers did not have any significant difference with the ones with negative HLA-B27 genotype. However; this genotype was associated with regurgitation of the aorta valve
Robust variational data assimilation of sparse velocity reference data in RANS simulations through a divergence-free forcing term
The Reynolds-averaged Navier-Stokes (RANS) equations offer a computationally
efficient way of solving fluid flow problems in engineering applications.
However, the use of closure models to represent turbulence effects can
compromise their accuracy. In order to address this issue, recent research has
explored data-driven techniques like data assimilation and machine learning. We
present an efficient variational data assimilation (DA) approach to enhance
steady-state RANS simulations based on eddy viscosity closure models. Our
method introduces a corrective forcing term based on a potential field that is
divergence-free and enhances simulation accuracy. The DA implementation relies
on the discrete adjoint method and approximations for efficient gradient
evaluation. The implementation is built on a two-dimensional coupled RANS
solver in \emph{OpenFOAM}, which is extended to allow the computation of the
adjoint velocity and pressure as well as the adjoint gradient. A gradient-based
optimizer is employed to minimize the difference between the simulation results
and the reference data. To assess this approach, it is compared with
alternative data assimilation methods for canonical stationary two-dimensional
turbulent flow problems. For the DA, sparsely distributed data from averaged
high-fidelity simulation results are used. The findings indicate that the
proposed method achieves the optimization goal more efficiently compared to
applying data assimilation for obtaining the eddy viscosity, or a field
modifying the eddy viscosity, directly. It is sturdy with respect to varying
the regularization parameters and the number of reference data points, and runs
efficiently by leveraging coarse meshes.Comment: 23 pages, 13 figure
Prevalence of Catheter-associated bacteriuria in patients who received short-term catheterization in the northeast of Iran
Background: Catheter-associated (CA) bacteriuria is a result of the extensive usage of urinary catheterization. Once a catheter is placed, many patients achieve bacteriuria, even with the use of greatest consideration and care of the catheter. In this study, we decided to evaluate the prevalence of Catheter-associated bacteriuria in patients who received short-term catheterization in the northeast of Iran.Materials and Methods: In this cross-sectional study during one year (among 2014-2015) 275 patients who have admitted recently and have no history of catheterization and drug consumption were included. Three samples were taken from patients before, one day after catheterization and after removal of the catheter. The urine samples were analyzed and cultured on the suitable media. Antibiotics susceptibility testing was performed by disk diffusion method. Then, data analyzed using SPSS software by Student t-test. In addition, the p values less than 0.05 were considered as significant.Results: In general, the rate of catheter-associated bacteriuria in these hospitals was 68% (187 cases of 275). The mean age of the participants and patients with bacteriuria were 41±1.2 and 24.8±6.2 years old, respectively. The most common isolated bacteria were Escherichia coli (50.6%) followed by Staphylococcus aureus and Klebsiella pneumonia (21.6%). The highest sensitivity was reported against kanamycin (68.9%) and highest resistance was observed against ampicillin with a rate of 96.3%.Conclusion: For prevention of healthcare-associated UTI, correct catheterization and use of the closed catheter system is recommended. In addition, before prescribing any antibiotics it should be paying attention to the antibiotics susceptibility testing results
Study of drug resistance of Staphylococcus aurous and Pseudomonas aeruginosa strains isolated from environmental samples of Hamadan educational hospitals in 2017 using disk diffusion and minimum inhibitory concentration
Background: Staphylococcus aureus and Pseudomonas aeruginosa are the most important bacteria causing the nosocomial infections, which are resistant to most of the antibiotics. The aim of this study was to evaluate the drug resistance of S. aureus and P. aeruginosa strains isolated from environmental samples of Hamedan educational hospitals using disk diffusion and minimum inhibitory concentration (MIC) methods. Materials and Methods: In this descriptive cross-sectional study, 400 samples were collected from Hamedan educational hospitals. To assess the antibiotic susceptibility of 10 common antibiotics, the agar dilution (Kirby-Bauer) method was used. Also, to determine the MIC of S. aureus and P. aeruginosa, vancomycin and ciprofloxacin antibiotics were used. Results: From a total of 400 samples, 39 (9.7) isolates were P. aeruginosa and 28 (7) were S. aureus. Staphylococcus aureus showed the highest resistance to ofloxacin (82.1) and the highest drug resistance to P. aeruginosa was related to meropenem (82). Also, the highest MIC and maximum bactericidal concentration (MBC) for S. aureus to vancomycin were 128 and 256, respectively. In P. aeruginosa, the highest MIC and MBC to ciprofloxacin were 128 and 256, respectively. Conclusion: Staphylococcus aureus and P. aeruginosa showed the highest resistance to ofloxacin and meropenem, respectively. Considering the rapid increase of antibiotic resistance, accurate evaluation of the antibiotic resistance pattern of the bacteria is required
Morphological study on biologically distinct vpx/vpr mutants of HIV-2
We have previously shown that human immunodeficiency virus type 2 (HIV-2) without functional vpx and vpr genes is severely defective for viral growth in lymphocytic cells, and suggested that the virions produced in the absence of Vpx and Vpr are critically damaged. To examine the nature of replication-defect for the vpx/vpr double mutant, we quantitatively and morphologically studied the virions produced in cells transfected or infected with wild type clone, single (vpx and vpr mutants) or the double mutant. While no significant difference in virion production was found for various virus clones in transfected cells, a major growth retardation in infected cells was readily observed for the vpx and vpx/vpr mutants. In particular, no viral growth was detected for the double mutant. By contrast to the very distinct growth characteristics of the three mutant clones, no appreciable difference in virion morphology was noted. These results indicated that Vpx and Vpr of HIV-2 may cooperatively contribute to virion infectivity without affecting virion morphogenesis
The incidence of cytomegalovirus glycoprotein B genotypes in kidney transplant recipients in Iran
Background: Cytomegalovirus (CMV) is the most common opportunistic viral infection in kidney transplant recipients. CMV classification is usually based on its glycoprotein B (gB) genotypes, which divides the virus into 4 strains (gB1�4). Objective: To determine the incidence of CMV genotypes in Iran and their relation to various clinical factors. Methods: We studied 80 renal transplant recipients admitted to our transplant referral center between 2014 and 2015. All of the studied patients were monitored every 1�2 weeks for CMV infection by immunofluorescence method. There were 34 CMV-infected patients whose sera were studied with sequencing technique to identify the 4 CMV genotypes. All patients were followed up to 6 months after transplantation. Results: gB1 was the most common genotype (35.3); it was followed by gB3 and gB4 (each with 17.6 ), gB2, and mixed gB1,3 and gB1,2 (each with 14.7). Age (p=0.037), time of infection after transplantation (p=0.011), and biopsy-proven rejection (p=0.012) were associated with CMV genotype. After adjusting for covariates, significant associations were found between genotype gB1 and family relationship (p=0.047) as well as HLA mismatch (p=0.014); genotype gB3 and family relationship (p=0.011); and genotype gB4 and age (p=0.019). Conclusion: The most common CMV gB genotype in CMV-infected kidney transplant recipients in Iran was gB1. We recommend considering related therapeutic applications in the management of such patients. © 2018 Iranian Society for Organ Transplantation. All rights reserved
In vitro evaluation of inhibitory effect of Lactobacillus reuteri supernatant on the replication of herpes simplex virus type 1 and expression of UL54, UL52 and UL27 genes
Background and Objectives: Human herpes virus type 1 (HSV-1) is a neurotropic pathogen that is infected more than 70% of the world population. The increasing of viral resistance to antiviral drugs and the emergence of side effects has motivated researchers to study the use of probiotics as new antiviral agents. The aim of the present study was to study for the first time the potential antiviral activity of Lactobacillus reuteri (L. reuteri) supernatant against HSV-1.
Materials and Methods: After measuring the cytotoxicity of L. reuteri supernatant by MTT assay, 1:16 dilution of it was added to HeLa cells before and after HSV-1 infection, after 1.5 hours incubation with HSV-1, and simultaneously with HSV-1 infection. After 48 hours of incubation at 37°C, the viral titer and expression levels of UL54, UL52 and UL27 genes were measured by tissue culture infectious dose 50 (TCID50) and Real-Time PCR methods, respectively.
Results: HSV-1 titer in the treatment conditions before infection, incubation with HSV-1, simultaneously with infection and after infection was reduced by 0.42, 3.42, 1.83, and 0.83 log 10 TCID50/ml, respectively. When the bacterial supernatant was first incubated with the virus and then added to the cell, or when it was added simultaneously with the virus, the expression of the UL27, UL52, and UL54 genes decreased significantly (p0.05).
Conclusion: The study findings indicated that the supernatant of L. reuteri has a potent anti-HSV-1 effect especially if it is incubated with the virus before inoculation into the cell. Its possible antiviral mechanism is to inhibit the virus by binding to it or changing the surface structure of the virus. Metabolites of L. reuteri can be considered as a novel inhibitor of HSV-1infection
Prevalence of Transfusion-transmitted Virus (TTV) infection and its association with renal posttransplantation complications in iran
Background: Transfusion-transmitted virus (TTV) is a single-stranded DNA virus. Renal transplant patients have a higher risk of TTV infection. Objective: To evaluate the prevalence of TTV and its correlation with post-renal transplantation complications in a population of Iranian patients. Methods: A cross-sectional study was performed on 120 renal transplant recipients. TTV infection in the peripheral blood samples was detected by semi-nested polymerase chain reaction (semi-nested PCR). Then, the relationship between TTV and renal post-transplant complications was examined. Results: 34.2 renal transplant recipients were positive for TTV. There was a significant correlation between the presence of TTV and diabetes, acute transplant rejection, and urinary tract infection. We did not find any direct correlation between the presence of TTV infection and hypertension, hyperlipidemia, respiratory tract infection, and cytomegalovirus infection. Conclusion: We found an increased rate of TTV infection in renal transplant recipients associated with post-transplantation complications. TTV may be an important risk factor for some post-renal transplantation complications. © 2018, Iranian Society for Organ Transplantation
Generation and characterization of APOBEC3G-positive 293T cells for HIV-1 Vif study
We have established a number of 293T cell lines that express a human anti HIV-1 factor APOBEC3G. Out of seven cell clones examined, four were readily demonstrated to express APOBEC3G by immunoblotting analysis. In particular, two clones (A3G-C1 and -C4) were found to produce a much higher level of functional APOBEC3G relative to that by pooled cell clones. The transfection efficiency of all these cell clones were similar to that of the parental cells, producing a comparable level of virions upon transfection of wild type and vif -minus proviral DNA clones. Furthermore, the expression level of APOBEC3G in the best cell line (A3G-C1) was far much higher than those of an APOBEC3G-positive lymphocyte cell line and peripheral blood mononuclear cells. We finally monitored the incorporation of APOBEC3G into virions produced in A3G-C1. APOBEC3G was easily detected in progeny viral particles upon transfection of vif -minus proviral clone but not of wild type. These results indicated that our new A3G-C1 cell line is eminently useful for various studies on the interaction of human APOBEC3G and HIV-1 Vif
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