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Geomechanical properties of rocks such as uniaxial compressive strength (UCS) and modulus of elasticity (E) have been essentially evaluated for rock engineering projects as well as dam sites. In this paper, in order to estimate the parameters, some mathematical methods are proposed including multiple linear regression, multiple nonlinear regression, and artificial neural networks (ANNs). These methods were employed to predict UCS and E for limestone rocks in terms of P wave velocity, density, and porosity. The data of 105 rock samples from two different dam sites (located in Asmari Formation, Karun 4, and Khersan 3 dams) were obtained and analyzed for developing predictive models. Comparison of the multiple linear and nonlinear regressions and ANNs results indicated that respective ANN models were more acceptable for predicting UCS and E than the others. Also, it observed that between multiple linear and nonlinear regressions, second case has more capability to predict UCS. It should be noted that there were no strong relationships between the predicted and measured E in the both multiple regressions. [ABSTRACT FROM AUTHOR]

Despite advances in cancer therapies, glioblastoma (GBM) remains the most resistant and recurrent tumor in the central nervous system. GBM tumor microenvironment (TME) is a highly dynamic landscape consistent with alteration in tumor infiltration cells, playing a critical role in tumor progression and invasion. In addition, glioma stem cells (GSCs) with self-renewal capability promote tumor recurrence and induce therapy resistance, which all have complicated eradication of GBM with existing therapies. Oncolytic virotherapy is a promising field of therapy that can kill tumor cells in a targeted manner. Manipulated oncolytic viruses (OVs) improve cancer immunotherapy by directly lysis tumor cells, infiltrating antitumor cells, inducing immunogenic cell death, and sensitizing immune-resistant TME to an immune-responsive hot state. Importantly, OVs can target stemness-driven GBM progression. In this review, we will discuss how OVs as a therapeutic option target GBM, especially the GSC subpopulation, and induce immunogenicity to remodel the TME, which subsequently enhances immunotherapies' efficiency., Competing Interests: Declaration of competing interest The authors declare that the research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Epstein-Barr virus (EBV) associated gastric carcinoma (EBVaGC) is a subtype of gastric cancer with distinct histological and molecular features. The study aimed to assess the EBV DNA copy number and the prevalence of EBVaGC in gastric cancer samples taken from Iranian patients. The next aim was to assess whether the DNA and microRNAs EBV are present in plasma. EBV load was analyzed in 68 gastric cancer biopsies and compared with the results of EBV-encoded small RNA in situ hybridization (EBER-ISH) test in these patients. After the detection of 6 EBV miRNAs in gastric tissue by stem-loop RT-PCR, plasma samples were evaluated for the viral load and EBV miRNAs. Four gastric cancer cases were EBER -ISH positive (5.8%), with a significantly higher viral load than the remaining cases, 47,781 vs. 1909 copies/μg of tissue DNA. Here, was also found a significant difference in plasma EBV load between EBER-positive and EBER-negative cases. Although EBV miRNAs were detectable in all the EBER-positive tumors, the test did not detect any of these miRNAs among the plasma samples tested. Our data indicate that the prevalence of EBVaGC among Iranian patients with gastric cancer is lower than the global prevalence and although none of the EBV miRNAs were detected in plasma, evaluation of EBV microRNAs in tumor tissue, especially miR-BART7-3p, may constitute useful biomarkers for diagnosis of EBVaGC., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background and Objectives: Human rhinovirus (HRV), a major cause of common cold, was associated to the hospitalization of children and adults. This cross-sectional study aimed to determine the prevalence, and genotype distribution of HRV in the patients with mild to severe respiratory infections who were negative for SARS-Cov-2., Materials and Methods: Nasopharyngeal swab specimens (n = 356) from the patients aged 29 days to 82 years, received for the respiratory virus detection from January to December 2021, were analyzed for human rhinovirus (HRV) by RT-PCR. As a final step, genotyping was performed on obtained sequences., Results: A total of 37 HRV infections were identified (37/356, 10%). The highest rates of positive HRV tests were observed in February (21.6%), and January (18.9%), compared with June and August (0%). HRV-positive cases mainly appeared in winter. Among the age groups, those 2-<5 years of age had the highest detection rate (21%), however, those >55 years of age had the lowest detection rate (3%). Among HRV-positive samples, 30 (81%) were identified as type HRV-A, 5 (13.5%) as HRV-B, and 2 (5.5%) as HRV-C., Conclusion: Our results suggested that HRV frequency gradually decreased with the age of patients which is more active in Iran, especially in the cold months., (Copyright © 2023 The Authors. Published by Tehran University of Medical Sciences.)

Acute pancreatitis, a potentially fatal disease, with symptoms including nausea and/or vomiting, indigestion, and abdominal pain, is known to range from a mild self-limiting state up to a more severe and lethal form. This review aims to provide a clearer picture to improve understanding the role of viral agents in the development of acute pancreatitis. Common databases including PubMed, Google Scholar, and Scopus were used for the literature search. In this review search terms including virus, viral, infection, and specific descriptive terms for a virus were considered in different combinations. Various causative agents are recognized in the development of acute pancreatitis as one of the most frequent gastrointestinal diseases, such as gallstones, alcoholism, and hypertriglyceridemia. Microbial pathogens with about 10% of acute pancreatitis cases, mainly viruses, among other factors, are thought to play a role in this regard. Once the pancreatitis diagnosis has been made, depending on the causative agent, the management approach and specific interventions affect the final outcome. Virus-induced acute pancreatitis in patients should be considered. Advanced diagnostic tests such as PCR, in situ hybridization, and biopsy can help for a better understanding of the role of viruses in causing acute pancreatitis. Improvement in the tests will lead to timely diagnosis, treatment, and better management of pancreatitis., Competing Interests: The authors declare that they have no conflicts of interest., (© 2023, Gastroenterology and Hepatology From Bed to Bench (GHFBB).)

Human herpes viruses (HHVs) are among the most common infectious agents detected in the gastrointestinal tract that might be involved in oncogenesis and other gastrointestinal disorders. Although the link between the Epstein-Barr virus (EBV) and gastric cancer (GC) has been established, the role of the viruses in various stomach diseases remains unknown. The frequencies and viral copy number of EBV, cytomegalovirus (CMV), and human herpesvirus 6 (HHV-6) among 50 gastric cancer tumors and 105 chronic gastritis tissues were measured by quantitative real-time PCR. In the tumor specimens and the adjacent normal tissues EBV was found in 60% and 30.9%, CMV in 14% and 4.7%, and HHV-6 in 18%, and 14.2%, respectively. The detection rate of EBV and CMV was found to be significantly higher in tumor tissues relative to the adjacent normal tissues. Also, in chronic gastritis, the frequency of EBV, CMV, and HHV-6 was 19%, 12.3%, and 15.2%, respectively, compared with 16.4%, 1.1%, and 8.2% in their corresponding normal tissues. Here, the CMV frequency was found to be significantly higher in gastritis tissues relative to the adjacent normal tissues. Furthermore, viral load in both gastric cancer and gastritis groups was higher in either tumor or gastritis lesion compared with matched adjacent normal tissue. This study showed a clear association between gastric cancer with both EBV and CMV. Meanwhile, analyses revealed a strong association between the EBV, CMV, and HHV-6 viral loads with gastritis (P = 0.0026, P < 0.0001, and P = 0.0405, respectively). Our results suggest that these three viruses might contribute to the induction and development the gastritis and gastric cancer., (© 2022 The Societies and John Wiley & Sons Australia, Ltd.)

Aim: The current study aimed to investigate sequence variations in the C-terminus of latent membrane protein 1 (LMP1) in Epstein-Barr virus (EBV) isolates from Iranian patients with chronic gastritis or gastric cancer (GC)., Background: LMP1, an essential viral oncoprotein, is the critical element in the immortalization of B cells. It contains a small twenty-four amino acid cytoplasmic N-terminal region, six transmembrane segments, and a two hundred amino acid cytoplasmic C-terminal domain. Most LMP1-mediated signal transduction events are moderated by some functional parts of the cytoplasmic C-terminal domain., Methods: Thirty-two EBV-positive biopsy tissues were obtained from patients with gastric cancer and patients with chronic gastritis. The C-terminal nucleotide sequences of LMP1 were amplified using nested-PCR and analyzed by DNA sequencing., Results: Four to eight copies of the 11 repeat elements (codon 254-302) were observed in the carboxyl-terminal site of patients, but no relationship was found between the number of repeat sequences and disease status. The 30-bp deletion corresponding to codon 345-354 of the B95-8 strain was observed in 34% of isolates, and the remaining samples were non-deleted. In the gastric cancer group, a higher number of 33-bp repeats (≥5 repeats) was observed in 30-bp-deletion (100%) than in non-deleted (42%) isolates, and the difference was statistically significant. Analysis revealed that a gastritis isolate may be the result of recombination between Alaskan and China1 strains., Conclusion: Overall, the current results showed no association between C-terminal sequence variations of LMP1 and malignant or non-malignant isolate origin., Competing Interests: The authors declare that they have no conflict of interest., (©2022 RIGLD, Research Institute for Gastroenterology and Liver Diseases.)

This paper reviews epigenetic mechanisms by which influenza viruses affect cellular gene activity to control their life cycles, aiming to provide new insights into the complexity of functional interactions between viral and cellular factors, as well as to introduce novel targets for therapeutic intervention and vaccine development against influenza infections., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2021 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.)

Human Parvovirus B19 (B19V) is a prototype of the Erythroparvovirus genus in Parvoviridae family. B19V infections are often associated with fever and rash, and can be mistakenly reported as measles or rubella. Differential diagnosis of B19V illness is necessary for case management and also for public health control activities, particularly in outbreak situations in which measles or rubella is suspected. To investigate the causative role of B19V infection in children with measles- and rubella-like illness, a total of 583 sera from children with exanthema were tested for presence of B19V by determining anti-B19V IgG and IgM antibodies by ELISA as well as B19V DNA detection by nested PCR. DNA positive samples were assessed further for determination of viral load and sequence analysis by Real-Time PCR and Sanger sequencing method, respectively. Out of 583 patients, 112 (19.21%) patients were positive for B19V-IgM antibody, 110 (18.87%) were positive for B19V-IgG antibody, and 63 (10.81%) were positive for B19V viral DNA. The frequency of B19V-IgG antibodies were increased with age; that is children under 6 year old showed 7.11% seroprevalence for B19V-IgG as compared to 18.39% and 28.91% for age groups 6 to >11 and 11-14 years old, respectively. Phylogenetic analysis of the NS1-VPu1 overlapping region revealed that all sequenced B19V-DNA belonged to genotype 1. The results of this study may aid the surveillance programs aiming at eradicating measles/rubella virus in Iran, as infections with B19V can be mistakenly reported as measles or rubella if laboratory testing is not conducted., (© 2015 Wiley Periodicals, Inc.)