Measurement method of in-situ tensile strength of SiC fiber in SiC/SiC composite

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An autoencoder-classified cluster of SARS-CoV-2 strain with two mutations in helicase

Using an autoencoder-based analysis to classify genomes of SARS-CoV-2 coronaviruses, we found a cluster consisting only of a specific genotype with two mutations in the helicase. This virus genotype, called C-type SARS-CoV-2, was almost exclusively prevalent in the United States from March to July 2020. This type of virus, characterized by a pair of the C17747T (P504L) and A17858G (Y541C) mutations on the nsp13 gene, had never been highly prevalent at any other time or in any other part of the world. In the U.S., Washington State was the center of the epidemic, and the C-type viruses, along with the viruses with wild-type helicase, seemed to have aroused the pandemic. In Washington State, USA, the CoViD-19 epidemic during the first two months of the year, starting at the end of February 2020, was mainly caused by the type-C virus. During this period, the infection spread rapidly; from May onwards, the number of viruses with wild-type helicases became higher than that of type-C viruses, and no type-C viruses have been collected since early July. The involvement of the helicase in this COVID-19 disease was discussed

Population analysis of oseltamivir-resistant variants for the rapid prediction of drug susceptibility by real-time reverse transcription polymerase chain reaction

This study investigated whether quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), using specific probes composed of locked nucleic acids (LNA/qRT-PCR), designed to evaluate H1N1 pdm09 H275Y, H3N2 E119V and R292K variant populations, could replace a neuraminidase (NA) inhibition assay to determine the 50% inhibitory concentration (IC50) of NA activity.For H1N1 pdm09, when the H275Y variant RNA load was 50% or 70% and the infective H275Y variant load was 40% or 70%, the IC50 were >10- and 100-fold higher, respectively, than that of the wild-type (WT) strain. For H3N2, when the E119V RNA load and infective E119V variant load were >90% and >60%, respectively, the IC50 of the mixed sample was >10-fold higher than that of the WT strain. The variant-mixed samples with a 70% or 80% R292K variant RNA load and a 60% or 70% infective R292K variant load exhibited >10- and 100-fold decreased susceptibility, respectively, compared with that of the WT. A positive correlation between the variant RNA load and infective variant load populations was observed.The LNA/qRT-PCR method can be used to improve the treatment and management of patients during antiviral therapy for influenza virus infection

RSV replication is attenuated by counteracting expression of the suppressor of cytokine signaling (SOCS) molecules

AbstractHuman RSV causes an annual epidemic of respiratory tract illness in infants and in elderly. Mechanisms by which RSV antagonizes IFN-mediated antiviral responses include inhibition of type I IFN mRNA transcription and blocking signal transduction of JAK/STAT family members. The suppressor of cytokines signaling (SOCS) gene family utilizes a feedback loop to inhibit cytokine responses and block the activation of the JAK/STAT signaling pathway. To evaluate the potential of SOCS molecules to subvert the innate immune response to RSV infection, eight SOCS family genes were examined. RSV infection up-regulated SOCS1, SOCS3, and CIS mRNA expression in HEp-2 cells. Suppression of SOCS1, SOCS3 and CIS by short interfering ribonucleic acid (siRNA) inhibited viral replication. Furthermore, inhibition of SOCS1, SOCS3, or CIS activated type I IFN signaling by inducing STAT1/2 phosphorylation. These results suggest that RSV infection escapes the innate antiviral response by inducing SOCS1, SOCS3 or CIS expression in epithelial cells

Clinical course and background of nasopharyngeal antibiotic-resistant bacteria carriers among preschool children hospitalized for lower respiratory tract infection

Abstract We investigated the nasopharyngeal microbiota in preschool patients hospitalized with lower respiratory tract infection to clarify the relationships between culturable nasopharyngeal bacteria and prognosis. From 2016 to 2018, nasopharyngeal culture was performed on inpatients under 6 years of age with a lower respiratory tract infection. Among the 1,056 study patients, 1,046 provided nasopharyngeal samples that yielded positive cultures, yielding 1,676 isolated strains. Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis, were isolated in 25%, 27%, and 31% of the samples, respectively, and were the major causes of respiratory tract infection in these children. The only factor associated with the isolation of antibiotic-resistant strains from the nasopharynx was daycare attendance, which did not affect clinical severity, such as duration of fever and hospitalization. This study demonstrated that resistant bacteria in the nasopharynx did not affect the severity of lower respiratory tract infection and supports the use of narrow-spectrum antimicrobial agents in accordance with published guidelines when initiating therapy for pediatric patients with community-acquired pneumonia

Factors affecting the choice of delivery place in a rural area in Laos: A qualitative analysis

Background: Home delivery (HD) without skilled birth attendants (SBAs) are considered crucial risk factors increasing maternal and child mortality rates in Loa PDR. While a few studies in the literature discuss the choice of delivery in remote areas of minority ethnic groups; our work aims to identify factors that indicated their delivery place, at home or in the health facilities.Methods: A community-based qualitative study was conducted between February and March 2020. Three types of interviews were implemented, In-depth interviews with 16 women of eight rural villages who delivered in the last 12 months in Xepon District, Savannakhet Province, Lao PDR. Also, three focus group discussions (FGDs) with nine HCPs and key-informant interviews of ten VHVs were managed. Factors affecting the choice of the delivery place were categorized according to the social-ecological model.Results: Our sample included five Tri women and two Mangkong women in the HD group, while the FD group included three Tri women, two Mangkong women, one Phoutai woman, two Laolung women and one Vietnamese. Our investigation inside the targeted minority showed that both positive perceptions of home delivery (HD) and low-risk perception minorities were the main reasons for the choice of HD, on the individual level. On the other hand, fear of complication, the experience of stillbirth, and prolonged labour pain during HD were reasons for facility-based delivery (FD). Notably, the women in our minority reported no link between their preference and their language, while the HCPs dated the low knowledge to the language barrier. On the interpersonal level, the FD women had better communication with their families, and better preparation for delivery compared to the HD group. The FD family prepared cash and transportation using their social network. At the community level, the trend of the delivery place had shifted from HD to FD. Improved accessibility and increased knowledge through community health education were the factors of the trend. At the societal (national policy) level, the free delivery policy and limitation of HCPs’ assisted childbirth only in health facilities were the factors of increasing FD, while the absence of other incentives like transportation and food allowance was the factor of remaining of HD.Conclusions: Based on the main findings of this study, we urge the enhancement of family communication on birth preparedness and birthplace. Furthermore, our findings support the need to educate mothers, especially those of younger ages, about their best options regarding the place of delivery. We propose implementing secondary services of HD to minimize the emergency risks of HD. We encourage local authorities to be aware of the medical needs of the community especially those of pregnant females and their right for a free delivery policy

Modern contraceptive use among adolescent girls and young women in Benin: a mixed-methods study

Objectives: The study aimed to assess the determinants of modern contraceptive method use among young women in Benin.Design: A mixed-methods design.Setting and participants: We used the Benin 2017–2018 Demographic and Health Survey datasets for quantitative analysis. Data collection was conducted using multiple-cluster sampling method and through household survey. Qualitative part was conducted in the city of Allada, one of the Fon cultural capitals in Benin. The participants were purposively selected.Outcomes: Contraceptive prevalence rate, unmet need for modern method and percentage of demand satisfied by a modern method for currently married and sexually active unmarried women were measured in the quantitative part. Access barriers and utilisation of modern methods were assessed in the qualitative part.Results: Overall, 8.5% (95% CI 7.7% to 9.5%) among young women ages 15–24 were using modern contraceptives and 13% (12.1% to 14.0%) among women ages 25 or more. Women 15–24 had a higher unmet need, and a lower demand satisfied by modern contraceptive methods compared with women ages 25 or more. 60.8% (56.9% to 64.7%) of all unmarried young women had unmet need for modern contraceptives. Young women were more likely to use male condoms which they obtain mainly from for-profit outlets, pharmacies and relatives. The factors associated with demand satisfied by a modern method were literacy, being unmarried, knowing a greater number of modern contraceptive methods and experiencing barriers in access to health services. On the other hand, the qualitative study found that barriers to using modern methods include community norms about pre-marital sexual intercourse, perceptions about young women’s fertility, spousal consent and the use of non-modern contraceptives.Conclusion: Contraceptive use is low among young women in Benin. The use of modern contraceptives is influenced by sociodemographic factors and social norms. Appropriate interventions might promote comprehensive sexuality education, increase community engagement, provide youth-friendly services and address gender inequalities

Plastic bronchitis associated with influenza B virus infection: A case report

Plastic bronchitis (PB) is a severe acute respiratory disease that develops as a result of the formation of branching mucus plugs in the bronchial tree. PB is known as a complication of influenza A virus infection, but some cases have been associated with influenza B virus infections. This patient was a 3-year-old boy with no history of allergic disease who developed PB requiring ventilator management after influenza B virus infection. He was hospitalized and managed with ventilator support because of acute respiratory failure. Influenza B virus infection was diagnosed via rapid antigen test and real-time reverse-transcription polymerase chain reaction (RT-PCR). A bronchoscopy performed after a chest X-ray and computed tomography confirmed the presence of extensive atelectasis in the right lung field and mucus plugs in the right bronchus. The patient's respiratory condition improved rapidly after removal of the plugs. Quantitative real-time RT-PCR performed with nasal and aspirated sputum samples obtained at hospitalization revealed a higher viral RNA load in the upper rather than in the lower respiratory tract. Viral replication in the lower respiratory was not found to be a major contributor toward mucus plug formation. The finding of increased serum IgE in the absence of a history of allergic disease suggests that an allergic reaction contributed to the formation of mucus plugs