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Background: With an overall adult HIV prevalence of 15.3%, Namibia is facing one of the largest HIV epidemics in Africa. Young people aged 20 to 34 years constitute one of the groups at highest risk of HIV infection in Namibia. However, little is known about the impact of HIV on this group and its access to healthcare. The purpose of this study was to estimate HIV prevalence, to assess the knowledge of and attitudes towards HIV/AIDS, and to assess access to healthcare among university students in Namibia. Methods: We assessed HIV/AIDS knowledge and attitudes, HIV prevalence and access to healthcare among students at the Polytechnic of Namibia and the University of Namibia. HIV prevalence was tested through anonymous oral fluid‐based tests. Results: Half (n = 2790/5568) of the university students and 45% (n = 2807/6302) of the Polytechnic students participated in the knowledge and attitudes surveys. HIV/AIDS knowledge was reasonable, except for misperceptions about transmission. Awareness of one's own HIV status and risks was low. In all, 55% (n = 3055/5568) of university students and 58% (n = 3680/6302) of Polytechnic students participated in the HIV prevalence survey; 54 (1.8%) university students and 103 (2.8%) Polytechnic students tested HIV positive. Campus clinics were not the major providers of healthcare to the students. Conclusions: Meaningful strategies addressing the gap between knowledge, attitude and young people's perception of risk of HIV acquisition should be implemented. HIV prevalence among Namibian university students appears relatively low. Voluntary counselling and testing should be stimulated. Efforts should be made to increase access to healthcare through the campus clinics., Background Namibia in southern Africa has approximately 2.2 million inhabitants and is classified as a middle‐income country. The Namibian health system has both a public health service through the Ministry [...]

Objectives: Respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory infection (ALRI) in young children. With substantial advances in RSV research, we aimed to conduct an updated systematic review of risk factors for RSV-ALRI in children under 5 years., Methods: We updated our previously published literature search to November 2022 among three English databases and additionally searched three Chinese databases (from January 1995) to identify all relevant publications. We performed random-effects meta-analyses to estimate the pooled odds ratio (OR) and 95% confidence interval (CI) for each risk factor and each outcome (RSV-ALRI in the community and RSV-ALRI hospitalization)., Results: A total of 47 studies were included (26 from the updated search). Indoor air pollution was identified as a possible risk factor for RSV-ALRI in the community (OR 1.45, 95% CI: 1.10-1.90). The identified risk factors for RSV-ALRI hospitalization fall into four categories: demographic (male sex, Māori and Pacific ethnicities vs European or other ethnicities), pre- and post-neonatal (prematurity, low birth weight, small for gestational age, maternal smoking during pregnancy or lactation, maternal age <30 years vs 30-34 years, multiparity, caesarean section vs vaginal), household and environmental (having siblings, passive smoking, maternal asthma, daycare centre attendance) and health and medical conditions (any chronic diseases, bronchopulmonary dysplasia, HIV infections, congenital heart disease, Down syndrome, cystic fibrosis, previous asthma). The pooled ORs ranged from 1.14 to 4.55., Conclusion: Our findings on the risk factors for RSV-ALRI help identify RSV high-risk groups, which has important implications for RSV prevention at both individual and population levels., Competing Interests: Declarations of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: YL reports grants from WHO, GSK and Wellcome Trust; and personal fees from WHO and Pfizer, outside the submitted work. HN reports grants from the Innovative Medicines Initiative, WHO, the National Institute for Health Research, Pfizer and Icosavax; and personal fees from the Bill & Melinda Gates Foundation, Pfizer, GSK, Merck, Abbvie, Janssen, Icosavax, Sanofi, Novavax, outside the submitted work., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Abstract: Several single-arm studies have explored the inclusion of brentuximab vedotin (BV) in salvage chemotherapy followed by autologous stem cell transplantation (ASCT) for relapsed/refractory (R/R) classical Hodgkin lymphoma (cHL). However, no head-to-head comparisons with standard salvage chemotherapy have been performed. This study presents a propensity score-matched analysis encompassing individual patient data from 10 clinical trials to evaluate the impact of BV in transplant-eligible patients with R/R cHL. We included 768 patients, of whom 386 were treated with BV with or without chemotherapy (BV cohort), whereas 382 received chemotherapy alone (chemotherapy cohort). Propensity score matching resulted in balanced cohorts of 240 patients each. No significant differences were observed in pre-ASCT complete metabolic response (CMR) rates (P = .69) or progression free survival (PFS; P = .14) between the BV and chemotherapy cohorts. However, in the BV vs chemotherapy cohort, patients with relapsed disease had a significantly better 3-year PFS of 80% vs 70%, respectively (P = .02), whereas there was no difference for patients with primary refractory disease (56% vs 62%, respectively; P = .67). Patients with stage IV disease achieved a significantly better 3-year PFS in the BV cohort (P = .015). Post-ASCT PFS was comparable for patients achieving a CMR after BV monotherapy and those receiving BV followed by sequential chemotherapy (P = .24). Although 3-year overall survival was higher in the BV cohort (92% vs 80%, respectively; P < .001), this is likely attributed to the use of other novel therapies in later lines for patients experiencing progression, given that studies in the BV cohort were conducted more recently. In conclusion, BV with or without salvage chemotherapy appears to enhance PFS in patients with relapsed disease but not in those with primary refractory cHL., (© 2024 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

Current antiretroviral treatment fails to cure HIV-1 infection since latent provirus resides in long-lived cellular reservoirs, rebounding whenever therapy is discontinued. The molecular mechanisms underlying HIV-1 latency are complex where the possible link between integration and transcription is poorly understood. HIV-1 integration is targeted toward active chromatin by the direct interaction with a host protein, lens epithelium-derived growth factor (LEDGF/p75). LEDGINs are small-molecule inhibitors of the LEDGF/p75-integrase (IN) interaction that effectively inhibit and retarget HIV-1 integration out of preferred integration sites, resulting in residual provirus that is more latent. Here, we describe a single-cell branched DNA imaging method for simultaneous detection of viral DNA and RNA. We investigated how treatment with LEDGINs affects the location, transcription, and reactivation of HIV-1 in both cell lines and primary cells. This approach demonstrated that LEDGIN-mediated retargeting hampered the baseline transcriptional state and the transcriptional reactivation of the provirus, evidenced by the reduction in viral RNA expression per residual copy. Moreover, treatment of primary cells with LEDGINs induced an enrichment of provirus in deep latency. These results corroborate the impact of integration site selection for the HIV-1 transcriptional state and support block-and-lock functional cure strategies in which the latent reservoir is permanently silenced after retargeting. IMPORTANCE A longstanding question exists on the impact of the HIV-1 integration site on viral gene expression. This unsolved question has significant implications for the search toward an HIV-1 cure, as eradication strategies set up to reactivate and eliminate HIV-1 depend on the site where the provirus is integrated. The main determinant for integration site selection is the interaction of the HIV-1 integrase (IN) and the host chromatin targeting factor, LEDGF/p75. LEDGINs are small-molecule inhibitors of the LEDGF/p75-IN interaction that inhibit and retarget HIV-1 integration out of preferred integration sites. Using both LEDGINs and branched DNA (bDNA) imaging, we now investigated, in much detail, the impact of integration site selection on the three-dimensional location of the provirus, HIV-1 transcription, and reactivation. Our results provide evidence for a "block-and-lock" functional cure strategy that aims to permanently silence HIV-1 by LEDGIN-mediated retargeting to sites that are less susceptible to reactivation after treatment interruption.

Background: Several local studies showed that the 2009 influenza pandemic delayed the RSV season. However, no global-level analyses are available on the possible impact of the 2009 influenza pandemic on the RSV season., Objectives: We aim to understand the impact of the 2009 influenza pandemic on the RSV season., Methods: We compiled data from published literature (through a systematic review), online reports/datasets and previously published data on global RSV seasonality and conducted a global-level systematic analysis on the impact of the 2009 influenza pandemic on RSV seasonality., Results: We included 354 seasons of 45 unique sites, from 26 countries. Globally, the influenza pandemic delayed the onset of the first RSV season by 0.58 months on average (95% CI: 0.42, 0.73; maximum delay: 2.5 months) and the onset of the second RSV season by a lesser extent (0.25 months; 95% CI: 0.12, 0.39; maximum delay: 3.4 months); no delayed onset was observed for the third RSV season. The delayed onset was most pronounced in the northern temperate, followed by the southern temperate, and was least pronounced in the tropics., Conclusions: The 2009 influenza pandemic delayed the RSV onset on average by 0.58 months and up to 2.5 months. This suggests evidence of viral interference as well as the impact of public health measures and has important implications for preparedness for RSV season during the ongoing COVID-19 pandemic and future pandemics., (© 2021 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.)

To infect nondividing cells, HIV-1 needs to cross the nuclear membrane. The importin transportin-SR2 (TRN-SR2 or transportin-3) has been proposed to mediate HIV-1 nuclear import, but the detailed mechanism remains unresolved. The direct interaction of TRN-SR2 with HIV-1 integrase (IN) has been proposed to drive HIV-1 nuclear import. Alternatively, TRN-SR2 may play an indirect role by mediating nuclear import of cleavage and polyadenylation specificity factor 6 (CPSF6). To unravel the role of TRN-SR2, we designed CRISPR/Cas9 guide RNAs targeting different exons of TNPO3 . Although this approach failed to generate full knockouts, monoallelic knockout clones were generated with indel mutations. HIV-1 replication was hampered in those clones at the level of HIV-1 nuclear import without an effect on the cellular distribution of the TRN-SR2 cargoes CPSF6 or alternative splicing factor1/pre-mRNA splicing factor SF2 (ASF/SF2). Recombinant ΔV 105 TRN-SR2 expressed in clone 15.15 was 2-fold impaired for interaction with HIV-1 IN and classified as an interaction mutant. Our data support a model whereby TRN-SR2 acts as a cofactor of HIV-1 nuclear import without compromising the nuclear import of cellular cargoes. CRISPR/Cas9-induced mutagenesis can be used as a method to generate interface mutants to characterize host factors of human pathogens. IMPORTANCE Combination antiretroviral therapy (cART) effectively controls HIV-1 by reducing viral loads, but it does not cure the infection. Lifelong treatment with cART is a prerequisite for sustained viral suppression. The rapid emergence of drug-resistant viral strains drives the necessity to discover new therapeutic targets. The nuclear import of HIV-1 is crucial in the HIV-1 replication cycle, but the detailed mechanism remains incompletely understood. This study provides evidence that TRN-SR2 directly mediates HIV-1 nuclear import via the interaction with HIV-1 integrase. The interaction between those proteins is therefore a promising target toward a rational drug design which could lead to new therapeutic strategies due to the bottleneck nature of HIV-1 nuclear import.

The HIV-1 capsid protein performs multiple roles in virus replication both during assembly and particle release and during virus trafficking into the nucleus. In order to decipher the roles of capsid protein during early replication, a reliable method to follow its intracellular distribution is required. To complement existing approaches to track HIV-1 capsid during early infection, we developed an HIV-1 imaging strategy, relying on viruses incorporating enhanced green fluorescent protein (eGFP)-tagged capsid (CA-eGFP) protein and mCherry-tagged integrase (IN-mCherry). Wild-type infectivity and sensitivity to inhibition by PF74 point to the functionality of CA-eGFP-containing complexes. Low numbers of CA-eGFP molecules were located inside the viral core and imported into the nucleus without significant loss in intensity. Less than 5% of particles carrying both CA-eGFP and IN-mCherry retained both labelled proteins after nuclear entry, implying a major uncoating event at the nuclear envelope dissociating IN and CA. Still, 20% of all CA-eGFP-containing complexes were detected in the nucleus. Unlike for IN-mCherry complexes, addition of the integrase inhibitor raltegravir had no effect on CA-eGFP-containing complexes, suggesting that these may be not (yet) competent for integration. Our imaging strategy offers alternative visualization of viral capsid trafficking and helps clarify its potential role during integration. IMPORTANCE HIV-1 capsid protein (CA) builds a conical shell protecting viral genomic RNA inside the virus particles. Upon entry into host cells, this shell disassembles in a process of uncoating, which is coordinated with reverse transcription of viral RNA into DNA. After uncoating, a portion of CA remains associated with the viral DNA and mediates its nuclear import and, potentially, integration into host DNA. In this study, we tagged CA with eGFP to follow its trafficking in host cells and address potential CA roles in the nucleus. We found that while functional viruses import the tagged CA into the nucleus, this capsid protein is not part of integration-competent complexes. The roles of nuclear CA thus remain to be established., (Copyright © 2020 American Society for Microbiology.)

Only a small portion of human immunodeficiency virus type 1 (HIV-1) particles entering the host cell results in productive infection, emphasizing the importance of identifying the functional virus population. Because integration of viral DNA (vDNA) is required for productive infection, efficient vDNA detection is crucial. Here, we use click chemistry to label viruses with integrase coupled to eGFP (HIV IN-eGFP ) and visualize vDNA. Because click labeling with 5-ethynyl-2'-deoxyuridine is hampered by intense background staining of the host nucleus, we opted for developing HIV-1 reverse transcriptase (RT)-specific 2'-deoxynucleoside analogs that contain a clickable triple bond. We synthesized seven propargylated 2'-deoxynucleosides and tested them for lack of cytotoxicity and viral replication inhibition, RT-specific primer extension and incorporation kinetics in vitro , and the capacity to stain HIV-1 DNA. The triphosphate of analog A5 was specifically incorporated by HIV-1 RT, but no vDNA staining was detected during infection. Analog A3 was incorporated in vitro by HIV-1 RT and human DNA polymerase γ and did enable specific HIV-1 DNA labeling. Additionally, A3 supported mitochondria-specific DNA labeling, in line with the in vitro findings. After obtaining proof-of-principle of RT-specific DNA labeling reported here, further chemical refinement is necessary to develop even more efficient HIV-1 DNA labels without background staining of the nucleus or mitochondria., (© 2019 De Wit et al.)

The Moloney murine leukemia virus (MLV) is a prototype gammaretrovirus requiring nuclear disassembly before DNA integration. In the nucleus, integration site selection towards promoter/enhancer elements is mediated by the host factor bromo- and extraterminal domain (BET) proteins (bromodomain (Brd) proteins 2, 3 and 4). MLV-based retroviral vectors are used in gene therapy trials. In some trials leukemia occurred through integration of the MLV vector in close proximity to cellular oncogenes. BET-mediated integration is poorly understood and the nature of integrase oligomers heavily debated. Here, we created wild-type infectious MLV vectors natively incorporating fluorescent labeled IN and performed single-molecule intensity and Förster resonance energy transfer experiments. The nuclear localization of the MLV pre-integration complex neither altered the IN content, nor its quaternary structure. Instead, BET-mediated interaction of the MLV intasome with chromatin in the post-mitotic nucleus reshaped its quaternary structure., (© The Author(s) 2018. Published by Oxford University Press on behalf of Nucleic Acids Research.)

In vivo imaging of biological processes is an important asset of modern cell biology. Selectively reacting fluorophores herein are an important tool and click chemistry reactions take a large share in these events. 5-Ethynyl-2'-deoxyuridine (EdU) is well known for visualizing DNA replication, but does not show any selectivity for incorporation into DNA. Striving for specific visualization of virus replication, in particular HIV replication, a series of propargylated purine deoxynucleosides were prepared aiming for selective incorporation by HIV reverse transcriptase (RT). We here report on the synthesis and preliminary biological effects (cellular toxicity, HIV inhibitory effects, and feasibility of the click reaction) of these nucleoside analogues., Competing Interests: The authors declare no conflict of interest.

The human immunodeficiency virus (HIV) depends on cellular proteins, so-called cofactors, to complete its replication cycle. In search for new therapeutic targets we identified the DNA and RNA binding protein Y-box-binding Protein 1 (YB-1) as a cofactor supporting early and late steps of HIV replication. YB-1 depletion resulted in a 10-fold decrease in HIV-1 replication in different cell lines. Dissection of the replication defects revealed that knockdown of YB-1 is associated with a 2- to 5-fold decrease in virion production due to interference with the viral RNA metabolism. Using single-round virus infection experiments we demonstrated that early HIV-1 replication also depends on the cellular YB-1 levels. More precisely, using quantitative PCR and an in vivo nuclear import assay with fluorescently labeled viral particles, we showed that YB-1 knockdown leads to a block between reverse transcription and nuclear import of HIV-1. Interaction studies revealed that YB-1 associates with integrase, although a direct interaction with HIV integrase could not be unambiguously proven. In conclusion, our results indicate that YB-1 affects multiple stages of HIV replication. Future research on the interaction between YB-1 and the virus will reveal whether this protein qualifies as a new antiviral target., Competing Interests: The authors have declared that no competing interests exist.

The karyopherin transportin SR2 (TRN-SR2, TNPO3) is responsible for shuttling specific cargoes such as serine/arginine-rich splicing factors from the cytoplasm to the nucleus. This protein plays a key role in HIV infection by facilitating the nuclear import of the pre-integration complex (PIC) that contains the viral DNA as well as several cellular and HIV proteins, including the integrase. The process of nuclear import is considered to be the bottleneck of the viral replication cycle and therefore represents a promising target for anti-HIV drug design. Previous studies have demonstrated that the direct interaction between TRN-SR2 and HIV integrase predominantly involves the catalytic core domain (CCD) and the C-terminal domain (CTD) of the integrase. We aimed at providing a detailed molecular view of this interaction through a biochemical characterization of the respective protein complex. Size-exclusion chromatography was used to characterize the interaction of TRN-SR2 with a truncated variant of the HIV-1 integrase, including both the CCD and CTD. These experiments indicate that one TRN-SR2 molecule can specifically bind one CCD-CTD dimer. Next, the regions of the solenoid-like TRN-SR2 molecule that are involved in the interaction with integrase were identified using AlphaScreen binding assays, revealing that the integrase interacts with the N-terminal half of TRN-SR2 principally through the HEAT repeats 4, 10, and 11. Combining these results with small-angle X-ray scattering data for the complex of TRN-SR2 with truncated integrase, we propose a molecular model of the complex. We speculate that nuclear import of the PIC may proceed concurrently with the normal nuclear transport., (© 2017 by The American Society for Biochemistry and Molecular Biology, Inc.)

Nuclear entry is a selective, dynamic process granting the HIV-1 pre-integration complex (PIC) access to the chromatin. Classical analysis of nuclear entry of heterogeneous viral particles only yields averaged information. We now have employed single-virus fluorescence methods to follow the fate of single viral pre-integration complexes (PICs) during infection by visualizing HIV-1 integrase (IN). Nuclear entry is associated with a reduction in the number of IN molecules in the complexes while the interaction with LEDGF/p75 enhances IN oligomerization in the nucleus. Addition of LEDGINs, small molecule inhibitors of the IN-LEDGF/p75 interaction, during virus production, prematurely stabilizes a higher-order IN multimeric state, resulting in stable IN multimers resistant to a reduction in IN content and defective for nuclear entry. This suggests that a stringent size restriction determines nuclear pore entry. Taken together, this work demonstrates the power of single-virus imaging providing crucial insights in HIV replication and enabling mechanism-of-action studies., Competing Interests: The authors declare competing financial interests: Z.D. and F.C. are patent holders on patents related to LEDGF/p75 and LEDGINs. The other authors declare no competing financial interests.

Background: Autonomy is an important concept in psychiatry, but because it is a somewhat abstract and ambiguous notion, it is not applicable in its entirety in a psychiatric context. This becomes obvious in situations where patients are receiving long term care and treatment., Aim: To modify the concept of autonomy in such a way that it acquires an extra dimension that renders it applicable to daily psychiatric practice., Method: The literature was reviewed in order to find articles that reveal the tensions that arise between autonomy and dependence in psychiatry and that reflect the human characteristics that are concealed behind the modern concepts of autonomy, freedom and respect for autonomy., Results: Concepts such as person, identity, acknowledgement, dialogical ethics and life histories are used as an addition to the concepts of autonomy of Kant and Mill. A phenomenological and a context sensitive conception of autonomy is needed within the perspective of dialogical ethics. A dialogical perspective requires from psychiatric professionals a susceptibility for what the patient as a human being really has to say. On the basis of a dialogue where there is space and attention for life histories, backgrounds and the potentials of patients, a new perspective can be developed that is shared by the persons involved., Conclusion: In psychiatry, statements about real autonomy and genuine respect for autonomy are only truly meaningful within the context of doctors, nurses and patients. A hermeneutic approach to patients which involves dialogue creates new opportunities in the field of staff-patient relations.