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Defining con-founders that affect the reliability of diagnostic tests for coronavirus disease 2019 is vital to breaking the chain of infection. The elderly population is a higher risk group for the emerging virus. However, gender seems to exert a critical role in modifying the infection risk among women owing to hormonal changes. The menopause transition is an exceptional period for older women where the protective and immunomodulatory effects of the estrogen hormone are lost. Accordingly, attention should be given to postmenopausal women since they will have an increased risk compared to their pre-menopausal peers.  相似文献   
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Background:Modern technology has reduced physical workload and imposed high mental workload on the control room operators in industrial settings. The present study was conducted among control room operators to assess their mental workload, investigate their workability, examine the relationship between mental workload and workability, and determine the factors associated with workability.Methods:This cross-sectional study was carried out among 213 control room operators in six Iranian process industries. Task Load Index (NASA-TLX) was used to assess the mental workload, and Work Ability Index (WAI) was used to determine workability. The relationships between demographic characteristics and dimensions of mental workload and workability were examined by univariate tests. Logistic regression analysis was also used to determine the factors associated with the operators’ workability.Results:The results showed a high mental workload in the study population (82.38±8.8). Yet, the operators showed a good and excellent level of workability (56.4%). Pearson’s correlation coefficient revealed a significant inverse linear relationship between the mean score of mental workload and workability (r=-0.581). Besides, regression modeling demonstrated that mental demand (OR=0.90), temporal demand (OR=0.90), effort (OR=0.91), frustration (OR=0.92), from NASA-TLX subscales were significantly associated with workability. Moreover, mental and temporal demands were important factors associated with reduced workability.Conclusion:Monitoring tasks imposes high mental workload on the control room operators, which may result in adverse effects on their workability as well as on the safety of the system.Key words: Mental workload, NASA-TLX, work ability, control room  相似文献   
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The outbreak of the current coronavirus disease (COVID-19) occurred in late 2019 and quickly spread all over the world. The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) belongs to a genetically diverse group that mutates continuously leading to the emergence of multiple variants. Although a few antiviral agents and anti-inflammatory medicines are available, thousands of individuals have passed away due to emergence of new viral variants. Thus, proper surveillance of the SARS-CoV-2 genome is needed for the rapid identification of developing mutations over time, which are of the major concern if they occur specifically in the surface spike proteins of the virus (neutralizing analyte). This article reviews the potential mutations acquired by the SARS-CoV2 since the pandemic began and their significant impact on the neutralizing efficiency of vaccines and validity of the diagnostic assays.  相似文献   
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Seropositivity for HSV reaches more than 70% within the world population, and yet no approved vaccine exists. While HSV1 is responsible for keratitis, encephalitis, and labialis, HSV2 carriers have a high susceptibility to other STD infections, such as HIV. Induction of antiviral innate immune responses upon infection depends on a family of pattern recognition receptors called Toll‐like receptors (TLR). TLRs bridge innate and adaptive immunity by sensing virus infection and activating antiviral immune responses. HSV adopts smart tricks to evade innate immunity and can also manipulate TLR signaling to evade the immune system or even confer destructive effects in favor of virus replication. Here, we review mechanisms by which HSV can trick TLR signaling to impair innate immunity. Then, we analyze the role of HSV‐mediated molecular cues, in particular, NF‐κB signaling, in promoting protective versus destructive effects of TLRs. Finally, TLR‐based therapeutic opportunities with the goal of preventing or treating HSV infection will be discussed.  相似文献   
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Gastric cancer (GC) is the third leading cause of cancer mortality worldwide, with an overall 5-y survival rate of 25%. The majority of GCs are caused by infectious agents, including the bacterium Helicobacter pylori (H. pylori) and Epstein–Barr virus (EBV). Furthermore, inappropriate repair of DNA damage can also result in genomic instability, which has shown to be a key factor in carcinogenesis of different regions including gastric region. Present study was designed to explore the association between base excision repair pathway genes, PARP1 and APEX1 and gastric pathology and H. pylori infection. Two hundred gastric cancer tissue samples (114 H. pylori positive and 86 H. pylori negative) and adjacent uninvolved area taken as controls was used for expression analysis of BER pathway genes at mRNA level and protein levels using quantitative PCR (qPCR) and immunohistochemistry (IHC) respectively. Oxidative stress and DNA damage was also determined by measuring the level of antioxidant enzymes and comet assay respectively. Significant upregulation in PARP1 (p < 0.001) and APEX1 (p < 0.02) was observed in GC tissue samples compared to controls and this upregulation was more pronounced in H. pylori positive cases (HPGC) (PARP1, p < 0.02: APEX1, p < 0.04) than H. pylori negative cases (HNGC). Upregulation of BER pathway genes in HPGC was found correlated with smoking status (p < 0.0001), T stage (p < 0.01) and lymph node metastasis (p < 0.03). Moreover, immunohistochemical staining of BER pathway genes was found correlated with a number of clinicopathological characteristics such as tumor type (p < 0.03), tumor size (p < 0.01) and lymph node metastasis (p < 0.01). Expression levels of APEX1 and PARP1 gene also correlated with increased oxidative burden (p < 0.0001) and DNA damage (p < 0.001) in GC patients. Survival analysis showed that upregulation of PARP1 gene was associated with poor overall survival outcome of gastric cancer patients (HR = 2.04 (95% CI = 1.10–3.76; p < 0.02). Univariate and multivariate cox regression analysis showed the upregulated PARP1 gene (HR = 5.03; 95%CI (2.22–11.35); p = 0.0001), positive smoking status (HR = 3.58; 95%CI (1.67–7.65); p = 0.001), positive status for H pylori infection (HR = 4.38; 95%CI (1.82–10.56); p = 0.001) and advance N-stage (HR = 5.29; 95%CI (2.28–12.24); p = 0.0001) were independent prognostic factors for gastric cancer and may serve as a valuable biomarker for the diagnosis and progression of GC and can be helpful in developing individualized treatment strategies for treating GC.  相似文献   
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Thyroid cancer (TC) is known as the most prevalent form of endocrine malignancy. With regard to high heterogeneity of the nodules, problem of discriminating between benign and malignant ones in terms of pathological characteristics, as well as lack of appropriate molecular markers; significant efforts are being made to identify molecular markers that able to detect tumorous lesions. Survivin, the newest member of the family of proteins inhibiting cell apoptosis, has been recently considered as a novel molecule marker for cancer. Studies on TC have also demonstrated distinctive expression of survivin and its splice variants in cancer cells compared to normal ones. Therefore, detection of survivin expression and its new splice variants can be utilized to identify tumor nodules and distinguish them from non-cancerous ones, along with other routine laboratory methods.  相似文献   
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