Inhibition of SARS-associated coronvirus infection and replication by siRNA

published_or_final_versio

South African healthcare provider perspectives on transitioning adolescents into adult HIV care

Background. The first generation of South African (SA) children perinatally infected with HIV is entering adulthood, and there is now a pressing need for systematised transfer of these patients from paediatric to adult care.Objectives. Previous research has investigated the HIV healthcare transition in North America and Europe, yet none has been conducted in SA. Our study is the first to describe the perspectives of healthcare providers overseeing the transition in resource-limited settings.Methods. We approached healthcare providers working in government paediatric HIV clinics and hospitals in the Western Cape Province, SA. Seven physicians and counsellors in adolescent/paediatric care, representing five clinics, were  interviewed, and 43 completed a written survey. Interviews addressed the current state of the transition, barriers and facilitators, and model components. Interviews were assessed for major themes using framework analysis, while logistic regression was applied to survey responses to identify associations with measured covariates.Results. Analysis of interview transcripts revealed several overarching perspectives that were corroborated by survey responses. One barrier identified was the  healthcare providers’ difficulty in letting go of their relationships with the adolescent patients. Since healthcare providers regarded their patients as particularly  vulnerable, they felt a strong and protective attachment towards them. A second barrier identified was a lack of structure and effective communication between adult and paediatric providers; accordingly, healthcare providers feared that they were transferring their adolescents unprepared, to a judgemental, depersonalised and overburdened environment. All interviewees and a majority of survey respondents (>80%) agreed that the formation of adolescent support groups in adult care clinics as well as a later transition age would improve the transition process.Conclusion. This study highlights the need for a systematic healthcare transition for HIV-positive adolescents cared for in the Western Cape, while acknowledging the limitations of the current healthcare infrastructure. Several feasible   recommendations have been identified, including forming support groups and greater involvement of adolescent healthcare providers to facilitate the transition

Development of interfering RNA agents to inhibit SARS-associated coronavirus infection and replication.

published_or_final_versio

Potent inhibition of SARS-associated coronavirus (SCoV) infection and replication by type I interferons (IFN-α/β) but not by type II interferon (IFN-γ)

We sought to investigate the anti-severe acute respiratory syndrome (SARS)-associated coronavirus (SCoV) activities of type I (α and β) and type II (γ) interferons (IFN) in vitro. Type I IFNs protected cells from cytopathic effects (CPE) induced by SCoV, and inhibited viral genomic RNA replication in FRhk-4 cells (measured by quantitative RT-PCR) in a dose-dependent manner. Intracellular viral RNA copies were reduced 50% by IFN-α at a concentration of 25 U/ml and by IFN-β at a concentration of 14 U/ml. IFN-γ had fewer effects on inhibition of viral infection and replication. The type I IFN receptor signaling pathway in host cells is mainly involved in the inhibition of SCoV infection and replication. Type I IFNs could be used as potential agents for anti-SARS treatment.published_or_final_versio

Rapid quantification of semen hepatitis B virus DNA by real-time polymerase chain reaction

Aim: To examine the sensitivity and accuracy of real-time polymerase chain reaction (PCR) for the quantification of hepatitis B virus (HBV) DNA in semen. Methods: Hepatitis B viral DNA was isolated from HBV carriers' semen and sera using phenol extraction method and QIAamp DNA blood mini kit (Qiagen, Germany). HBV DNA was detected by conventional PCR and quantified by TaqMan technology-based real-time PCR (quantitative polymerase chain reaction (qPCR)). The detection threshold was 200 copies of HBV DNA for conventional PCR and 10 copies of HBV DNA for real time PCR per reaction. Results: Both methods of phenol extraction and QIAamp DNA blood mini kit were suitable for isolating HBV DNA from semen. The value of the detection thresholds was 500 copies of HBV DNA per mL in the semen. The viral loads were 7.5×10 7 and 1.67×10 7 copies of HBV DNA per mL in two HBV infected patients' sera, while 2.14×10 5 and 3.02×10 5 copies of HBV DNA per mL in the semen. Conclusion: Real-time PCR is a more sensitive and accurate method to detect and quantify HBV DNA in the semen. © 2005 The WJG Press and Elsevier Inc. All rights reserved.published_or_final_versio

MiR-637 maintains the balance between adipocytes and osteoblasts by directly targeting Osterix

Bone development is dynamically regulated by homeostasis, in which a balance between adipocytes and osteoblasts is maintained. Disruption of this differentiation balance leads to various bone-related metabolic diseases, including osteoporosis. In the present study, a primate-specific microRNA (miR-637) was found to be involved in the differentiation of human mesenchymal stem cells (hMSCs). Our preliminary data indicated that miR-637 suppressed the growth of hMSCs and induced S-phase arrest. Expression of miR-637 was increased during adipocyte differentiation (AD), whereas it was decreased during osteoblast differentiation (OS), which suggests miR-637 could act as a mediator of adipoosteogenic differentiation. Osterix (Osx), a significant transcription factor of osteoblasts, was shown to be a direct target of miR-637, which significantly enhanced AD and suppressed OS in hMSCs through direct suppression of Osx expression. Furthermore, miR-637 also significantly enhanced de novo adipogenesis in nude mice. In conclusion, our data indicated that the expression of miR-637 was indispensable for maintaining the balance of adipocytes and osteoblasts. Disruption of miR-637 expression patterns leads to irreversible damage to the balance of differentiation in bone marrow. © 2011 Zhang et al.published_or_final_versio

High-throughput identification of genotype-specific cancer vulnerabilities in mixtures of barcoded tumor cell lines.

Hundreds of genetically characterized cell lines are available for the discovery of genotype-specific cancer vulnerabilities. However, screening large numbers of compounds against large numbers of cell lines is currently impractical, and such experiments are often difficult to control. Here we report a method called PRISM that allows pooled screening of mixtures of cancer cell lines by labeling each cell line with 24-nucleotide barcodes. PRISM revealed the expected patterns of cell killing seen in conventional (unpooled) assays. In a screen of 102 cell lines across 8,400 compounds, PRISM led to the identification of BRD-7880 as a potent and highly specific inhibitor of aurora kinases B and C. Cell line pools also efficiently formed tumors as xenografts, and PRISM recapitulated the expected pattern of erlotinib sensitivity in vivo

Domain-Based Identification and Analysis of Glutamate Receptor Ion Channels and Their Relatives in Prokaryotes

Voltage-gated and ligand-gated ion channels are used in eukaryotic organisms for the purpose of electrochemical signaling. There are prokaryotic homologues to major eukaryotic channels of these sorts, including voltage-gated sodium, potassium, and calcium channels, Ach-receptor and glutamate-receptor channels. The prokaryotic homologues have been less well characterized functionally than their eukaryotic counterparts. In this study we identify likely prokaryotic functional counterparts of eukaryotic glutamate receptor channels by comprehensive analysis of the prokaryotic sequences in the context of known functional domains present in the eukaryotic members of this family. In particular, we searched the nonredundant protein database for all proteins containing the following motif: the two sections of the extracellular glutamate binding domain flanking two transmembrane helices. We discovered 100 prokaryotic sequences containing this motif, with a wide variety of functional annotations. Two groups within this family have the same topology as eukaryotic glutamate receptor channels. Group 1 has a potassium-like selectivity filter. Group 2 is most closely related to eukaryotic glutamate receptor channels. We present analysis of the functional domain architecture for the group of 100, a putative phylogenetic tree, comparison of the protein phylogeny with the corresponding species phylogeny, consideration of the distribution of these proteins among classes of prokaryotes, and orthologous relationships between prokaryotic and human glutamate receptor channels. We introduce a construct called the Evolutionary Domain Network, which represents a putative pathway of domain rearrangements underlying the domain composition of present channels. We believe that scientists interested in ion channels in general, and ligand-gated ion channels in particular, will be interested in this work. The work should also be of interest to bioinformatics researchers who are interested in the use of functional domain-based analysis in evolutionary and functional discovery

Acetyltransferases and tumour suppression

The acetyltransferase p300 was first identified associated with the adenoviral transforming protein E1A, suggesting a potential role for p300 in the regulation of cell proliferation. Direct evidence demonstrating a role for p300 in human tumours was lacking until the recentl publication by Gayther et al, which strongly supports a role for p300 as a tumour suppressor. The authors identify truncating mutations associated with the loss or mutation of the second allele in both tumour samples and cell lines, suggesting that loss of p300 may play a role in the development of a subset of human cancers

Generation of a High Number of Healthy Erythroid Cells from Gene-Edited Pyruvate Kinase Deficiency Patient-Specific Induced Pluripotent Stem Cells

Pyruvate kinase deficiency (PKD) is a rare erythroid metabolic disease caused by mutations in the PKLR gene. Erythrocytes from PKD patients show an energetic imbalance causing chronic non-spherocytic hemolytic anemia, as pyruvate kinase defects impair ATP production in erythrocytes. We generated PKD induced pluripotent stem cells (PKDiPSCs) from peripheral blood mononuclear cells (PB-MNCs) of PKD patients by non-integrative Sendai viral vectors. PKDiPSCs were gene edited to integrate a partial codon-optimized R-type pyruvate kinase cDNA in the second intron of the PKLR gene by TALEN-mediated homologous recombination (HR). Notably, we found allele specificity of HR led by the presence of a single-nucleotide polymorphism. High numbers of erythroid cells derived from gene-edited PKDiPSCs showed correction of the energetic imbalance, providing an approach to correct metabolic erythroid diseases and demonstrating the practicality of this approach to generate the large cell numbers required for comprehensive biochemical and metabolic erythroid analyses.info:eu-repo/semantics/publishedVersio