Associations between teachers' professional competencies and the quality of interactions and relationships in preschool: findings from Austria.

The professionalization of preschool teachers is considered an important factor for ensuring and improving the quality of interactions and relationships. Findings on associations between teachers' professional competencies and the quality of interactions and relationships in preschools are not only inconsistent in general but also rare for early childhood education and care (ECEC) in Austria. Therefore, the aim of this study is to address this research gap by considering interaction quality at the child level (measured with the inCLASS) and preschool teachers' perceptions of the teacher-child relationship (measured with the STRS).

The impact of HIV infection on the frequencies, function, spatial localization and heterogeneity of T follicular regulatory cells (TFRs) within human lymph nodes.

Background: HIV eradication efforts have been unsuccessful partly due to virus persistence in immune sanctuary sites such as germinal centres within lymph node (LN) tissues. Recent evidence suggests that LNs harbour a novel subset of regulatory T cells, termed follicular regulatory T cells (TFRs), but their role in HIV pathogenesis is not fully elucidated.

Results: Paired excisional LN and peripheral blood samples obtained from 20 HIV-uninfected and 31 HIV-infected treated and 7 chronic untreated, were used to determine if and how HIV infection modulate frequencies, function and spatial localization of TFRs within LN tissues.

Hypermethylation at the CXCR5 gene locus limits trafficking potential of CD8+ T cells into B-cell follicles during HIV-1 infection.

CD8+ T cells play an important role in HIV control. However, in human lymph nodes (LNs), only a small subset of CD8+ T cells express CXCR5, the chemokine receptor required for cell migration into B-cell follicles, which are major sanctuaries for HIV persistence in individuals on therapy. Here, we investigate the impact of HIV infection on follicular CD8+ T cell (fCD8) frequencies, trafficking patterns, and CXCR5 regulation.

Transmission dynamics of SARS-CoV-2 within-host diversity in two major hospital outbreaks in South Africa.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes acute, highly transmissible respiratory infection in humans and a wide range of animal species. Its rapid global spread has resulted in a major public health emergency, necessitating commensurately rapid research to improve control strategies. In particular, the ability to effectively retrace transmission chains in outbreaks remains a major challenge, partly due to our limited understanding of the virus' underlying evolutionary dynamics within and between hosts.