Detection of hepatitis B virus covalently closed circular DNA in the plasma of Iranian HBeAg-negative patients with chronic hepatitis B

Background: Covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) is a marker of HBV replication in the liver of patients infected with HBV. Objectives: This study aimed to investigate the association between the presence of cccDNA in the plasma samples of Iranian treatment-naive patients with chronic hepatitis B infection and HBV viral load and HBsAg levels. Patients and Methods: From April 2012 to May 2015, 106 treatment-naive patients with chronic hepatitis B infection were enrolled in this cross-sectional study. The HBsAg titer was measured by the Roche HBsAg II assay on the Cobas e411 system, and HBV DNA quantitation was performed using the COBAS TaqMan 48 kit. Real-time polymerase chain reaction was performed for the detection of HBV cccDNA. Results: The mean (SD) age of the patients was 41.1 ± 12.4 years (range, 20 - 62 years). From a total of 106 study participants, 67 (63.2) were males. The HBV cccDNA was detected in plasma specimens in 19 (17.9) out of the total 106 patients, and a significant relationship was found between the presence of cccDNA in plasma sample of males (23.9) and females (7.7) (P = 0.039). Also, a significant correlation was found between the presence of cccDNA in plasma sample of the patients and HBV viral load level (P < 0.0001) and HBsAg titer (P = 0.0043). Conclusions: This study showed that cccDNA can be detected in the plasma specimen of 17.9 of Iranian treatment-naive patients with chronic hepatitis B infection. Therefore, designing prospective studies focusing on the detection of cccDNA in these patients would provide more information. © 2015, Kowsar Corp

Exosomal miRNAs: Novel players in viral infection

Exosomes are secreted nanovesicles that are able to transfer their cargo (such as miRNAs) between cells. To determine to what extent exosomes and exosomal miRNAs are involved in the pathogenesis, progression and diagnosis of viral infections. The scientific literature (PubMed and Google Scholar) was searched from 1970 to 2019. The complex biogenesis of exosomes and miRNAs was reviewed. Exosomes contain both viral and host miRNAs that can be used as diagnostic biomarkers for viral diseases. Viral proteins can alter miRNAs, and conversely miRNAs can alter the host response to viral infections in a positive or negative manner. It is expected that exosomal miRNAs will be increasingly used for diagnosis, monitoring and even treatment of viral infections. © 2020 Future Medicine Ltd

Computation of Eigenvalue-Eigenvector and Harmonic Motion Solution for Laminated Rubber-Metal Spring

This paper presents the modeling of multi-degree-of-freedom on laminated rubber-metal spring in axial direction displacement. Two methods are used which are firstly the eigenvalues and eigenvectors solution and secondly called harmonic motion solution. In eigenvalues and eigenvectors approach, equation of motion of laminated rubber-metal spring is developed using spring-mass system. Then, the equation was rewritten again in matrix and harmonic motion in order to reduce the difficulty and become realistic to be solved using characteristic equation. On the other hand, harmonic motion approach is started from governing equation in term of mode shape. By using this concept, two important equations are finally derived which are displacement and velocity. Using these two methods, finally the maximum displacements of laminated rubber-metal spring are plotted as well as in frequency domain axis. Two types of analysis are considered in this study which are undamped and damped system. Based on the results obtained, the maximum displacement occurred at undamped system. By increasing the number of degree-of-freedom, the displacement is slowly reduced

Product Design Improvement of Water Dispenser Tap using Triz Method

To produce the best solution for improving any product design that should be able to satisfy the design requirements (i.e., faster, better and cheaper), there were several stages typically involves the root cause analysis and idea generation activities. In this paper, product design improvement of a water dispenser is demonstrated using Theory of Inventive Problem Solving (TRIZ) method. The objective of this study was to find out the design solution which was able to solve the problem of water spill out that occurred after dispensing water from the dispenser tap. TRIZ Function Model and Engineering Contradiction method were used to model the problem, followed by TRIZ Contradiction Matrix and 40 Inventive Principles to generate potential solutions. The design improvement process based on the TRIZ method generated new concept design of water dispenser tap component which was able to eliminate the water spill out problem, while maintaining the existing dispensing function. In addition, the new dispenser tap conceptual design also required less component to operate compared with the existing design, hence, lowering the product cost

Thermal Analysis of Ventilated Disc Brake Rotor for UTeM Formula Varsity Race Car

A new design of disc brake using ventilated rotor was developed for the UTeM Formula Varsity racing car. Compacted graphite cast iron (CGI) was proposed as the material for the disc brake rotor. Thermal analysis was performed in this project to assess the component performance using ABAQUS/CAE v6.7-1 finite element analysis software both in transient condition. Results from the analysis show that the maximum temperature generated on the disc brake surface at the end of the braking procedure for transient condition was within the allowable service temperature of the ventilated rotor material. Thus, the new disc brake rotor is safe for operation and is expected to perform successfully as per design requirement

Investigation of the Mechanisms Underlying the Gastroprotective Effect of Cymbopogon Citratus Essential Oil

Cymbopogon citratus is a medicinal plant popularly used in Brazil for the treatment of various diseases, and the research interest in this plant is justifiable because of its potential medicinal value in stomachache and gastric ulcer. This study was aimed to test the validity of this practice by using experimental models of gastric ulcer and to clarify the mechanisms of gastroprotection by C. citratus leaves essential oil (EOCC). EOCC was evaluated for the ability to protect the gastric mucosa against injuries caused by necrotizing agents (absolute ethanol and aspirin) in rodents. The results of this study revealed that EOCC posses a dose-independent anti-ulcer effect against the different experimental models. EOCC pretreatment depicted a higher preventive index in ethanol-(88%) and aspirin-induced (76%) acute ulceration. On pretreatment of mice with indomethacin, the cyclooxygenase inhibitor slightly suppressed the gastroprotective effect of EOCC (48.5%). Furthermore, EOCC gastroprotection was not attenuated in mice pretreated with L-NAME (85.2%), glibenclamide (100%), or yohimbine (79.7%), the respective inhibitors of nitric oxide synthase, K+ATP channel activation, and α2 receptors. These results confirmed the traditional use of C. citratus for the treatment of gastric ulcer. Thus, we provide the first evidence that EOCC reduces gastric damage induced by ethanol, at least in part, by mechanisms that involve endogenous prostaglandins

Investigation of CTNNB1 gene mutations and expression in hepatocellular carcinoma and cirrhosis in association with hepatitis B virus infection

Hepatitis B virus (HBV), along with Hepatitis C virus chronic infection, represents a major risk factor for hepatocellular carcinoma (HCC) development. However, molecular mechanisms involved in the development of HCC are not yet completely understood. Recent studies have indicated that mutations in CTNNB1 gene encoding for β-catenin protein lead to aberrant activation of the Wnt/ β-catenin pathway. The mutations in turn activate several downstream genes, including c-Myc, promoting the neoplastic process. The present study evaluated the mutational profile of the CTNNB1 gene and expression levels of CTNNB1 and c-Myc genes in HBV-related HCC, as well as in cirrhotic and control tissues. Mutational analysis of the β-catenin gene and HBV genotyping were conducted by direct sequencing. Expression of β-catenin and c-Myc genes was assessed using real-time PCR. Among the HCC cases, 18.1 showed missense point mutation in exon 3 of CTNNB1, more frequently in codons 32, 33, 38 and 45. The frequency of mutation in the hotspots of exon 3 was significantly higher in non-viral HCCs (29.4) rather than HBV-related cases (12.7, P = 0.021). The expression of β-catenin and c-Myc genes was found upregulated in cirrhotic tissues in association with HBV infection. Mutations at both phosphorylation and neighboring sites were associated with increased activity of the Wnt pathway. The results demonstrated that mutated β-catenin caused activation of the Wnt pathway, but the rate of CTNNB1 gene mutations was not related to HBV infection. HBV factors may deregulate the Wnt pathway by causing epigenetic alterations in the HBV-related HCC. © 2020 The Author(s)

Large-scale magnetic fields from inflation due to a CPTCPT-even Chern-Simons-like term with Kalb-Ramond and scalar fields

We investigate the generation of large-scale magnetic fields due to the breaking of the conformal invariance in the electromagnetic field through the $CPT$-even dimension-six Chern-Simons-like effective interaction with a fermion current by taking account of the dynamical Kalb-Ramond and scalar fields in inflationary cosmology. It is explicitly demonstrated that the magnetic fields on 1Mpc scale with the field strength of $\sim 10^{-9}$G at the present time can be induced.Comment: 18 pages, 6 figures, version accepted for publication in Eur. Phys. J.