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91.
International Journal of Mental Health and Addiction - The current study aimed to determine the level of fear of COVID-19 among Indian residents using the Fear of COVID-19 Scale (FCV-19S) and...  相似文献   
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Journal of Clinical Immunology - T cell-Epstein-Barr virus–associated hemophagocytic lymphohistiocytosis (T cell-EBV-HLH) is prevalent in East Asia and has poor prognosis. Understanding of...  相似文献   
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Objective

To assess any potential association between Helicobacter pylori and oral squamous cell carcinoma/oral potentially malignant disorders.

Materials and methods

Data mining was done using PubMed, Cochrane Library, and SCOPUS databases. The search included articles published up to May 2019. Newcastle-Ottawa scale was used to score the quality of the included articles. Data including the type of study, the sample population, the type of oral lesion, and the resulting statistical data were extracted.

Results

Out of 131 screened articles, only 15 articles fulfilled the eligibility criteria. Among the 15 studies, 9 focused on oral squamous cell carcinoma and 6 focused on oral potentially malignant disorders. Eight out of the 9 oral squamous cell carcinoma studies were included in the meta-analysis. Forest plot was generated using the odds ratio and confidence intervals calculated for each of the included studies. Due to the lack of sufficient studies, the meta-analysis was not performed for oral potentially malignant disorders.

Conclusion

Due to the contradictory results of the included studies, it was not possible to make any conclusive statement on the potential association of H. pylori with oral squamous cell carcinoma. The variations in the methodology, especially the differences in the sensitivity/specificity of the diagnostic modalities could be the cause for differential results.

Clinical relevance

Although the association of H. pylori with oral squamous cell carcinoma could not be confirmed, it is vital to reduce the excess oral microbial load, especially in patients exhibiting oral mucosal changes with no history of associated risk factors.

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The mosquitocidal activity of different fractions and isolated compounds from the ethyl acetate extract of Ecbolium viride root was assessed on larvae and pupae of Culex quinquefasciatus Say (Diptera: Culicidae). The larvae and pupae were exposed to concentrations of 6.125, 12.5, 25 and 50 ppm for fractions and 1, 2.5, 5 and 10 ppm for compound. Among the 12 fractions screened, fraction 6 from the ethyl acetate extract of E. viride was recorded to have the highest larvicidal and pupicidal activities against C. quinquefasciatus. The lethal concentration (LC50 and LC90) values of fraction 6 were 4.26 and 9.0 ppm against C. quinquefasciatus larvae and 6.55 and 12.19 ppm against C. quinquefasciatus pupae, respectively, in 24 h. Fraction 7 was recorded to have moderate activity with LC50 and LC90 values of 11.25 and 25.02 ppm against C. quinquefasciatus larvae and 13.33 and 31.15 ppm against C. quinquefasciatus pupae, respectively, in 24 h. Ecbolin A and ecbolin B were identified from fractions 7 and 6, respectively. The structure of the isolated compounds was identified on the basis of spectral data (1H NMR and 13C NMR) and compared with literature spectral data. Further, the isolated compound, ecbolin B, from fraction 6 was recorded to have strong larvicidal and pupicidal activities than ecbolin A. The LC50 and LC90 values of ecbolin B on C. quinquefasciatus larvae were 1.36 and 2.76 ppm, and on pupae, these were 1.54 and 3.51 ppm, respectively. The present results suggest that ecbolin B could be used as a mosquitocidal agent against C. quinquefasciatus.  相似文献   
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Tetraspanins are integral transmembrane proteins organized in microdomains displaying specific and direct interactions with other tetraspanins and molecular partners. Among them, CD81 has been implicated in a variety of physiological and pathological processes. CD81 also plays a crucial role in pathogen entry into host cells, including hepatitis C virus (HCV) entry into hepatocytes. HCV is a major cause of liver cirrhosis and hepatocellular carcinoma. HCV entry into hepatocytes is a complex process that requires the coordinated interaction of viral and host factors for the initiation of infection, including CD81, scavenger receptor BI, claudin-1, occludin, membrane-bound host cell kinases, Niemann-Pick C1 Like 1, Harvey rat sarcoma viral oncogene homolog (HRas), CD63 and transferrin receptor 1. Furthermore, recent data in HCV model systems have demonstrated that targeting critical components of tetraspanins and associated cell membrane proteins open new avenues to prevent and treat viral infection.  相似文献   
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