Mutations in RAD21 disrupt regulation of apob in patients with chronic intestinal pseudo-obstruction

Background Aims Chronic intestinal pseudo-obstruction (CIPO) is characterized by severe intestinal dysmotility that mimics a mechanical subocclusion with no evidence of gut obstruction. We searched for genetic variants associated with CIPO to increase our understanding of its pathogenesis and to identify potential biomarkers. Methods We performed whole-exome sequencing of genomic DNA from patients with familial CIPO syndrome. Blood and lymphoblastoid cells were collected from patients and controls (individuals without CIPO); levels of messenger RNA (mRNA) and proteins were analyzed by quantitative reverse-transcription polymerase chain reaction, immunoblot, and mobility shift assays. Complementary DNAs were transfected into HEK293 cells. Expression of rad21 was suppressed in zebrafish embryos using a splice-blocking morpholino (rad21a). Gut tissues were collected and analyzed. Results We identified a homozygous mutation (p.622, encodes Ala>Thr) in RAD21 in patients from a consanguineous family with CIPO. Expression of RUNX1, a target of RAD21, was reduced in cells from patients with CIPO compared with controls. In zebrafish, suppression of rad21a reduced expression of runx1; this phenotype was corrected by injection of human RAD21 mRNA, but not with the mRNA from the mutated p.622 allele. rad21a Morpholino zebrafish had delayed intestinal transit and greatly reduced numbers of enteric neurons, similar to patients with CIPO. This defect was greater in zebrafish with suppressed expression of ret and rad21, indicating their interaction in the regulation of gut neurogenesis. The promoter region of APOB bound RAD21 but not RAD21 p.622 Ala>Thr; expression of wild-type RAD21 in HEK293 cells repressed expression of APOB, compared with control vector. The gut-specific isoform of APOB (APOB48) is overexpressed in sera from patients with CIPO who carry the RAD21 mutation. APOB48 also is overexpressed in sporadic CIPO in sera and gut biopsy specimens. Conclusions Some patients with CIPO carry mutations in RAD21 that disrupt the ability of its product to regulate genes such as RUNX1 and APOB. Reduced expression of rad21 in zebrafish, and dysregulation of these target genes, disrupts intestinal transit and the development of enteric neurons. © 2015 by the AGA Institute

Cyanobacterial assimilatory nitrate reductase gene diversity in coastal and oligotrophic marine environments

Cyanobacteria are important primary producers in many marine ecosystems and their abundances and growth rates depend on their ability to assimilate various nitrogen sources. To examine the diversity of nitrate-utilizing marine cyanobacteria, we developed PCR primers specific for cyanobacterial assimilatory nitrate reductase (narB) genes. We obtained amplification products from diverse strains of cultivated cyanobacteria and from several marine environments. Phylogenetic trees constructed with the narB gene are congruent with those based on ribosomal RNA genes and RNA polymerase genes. Analysis of sequence library data from coastal and oligotrophic marine environments shows distinct groups of Synechococcus sp. in each environment; some of which are represented by sequences from cultivated organisms and others that are unrelated to known sequences and likely represent novel phylogenetic groups. We observed spatial differences in the distribution of sequences between two sites in Monterey Bay and differences in the vertical distribution of sequence types at the Hawai\u27i Ocean Time-series Station ALOHA, suggesting that nitrogen assimilation in Synechococcus living in different ecological niches can be followed with the nitrate reductase gene. © 2006 The Authors

FcγRI activation of phospholipase Cγ1 and protein kinase C in dibutyryl cAMP-differentiated U937 cells is dependent solely on the tyrosine-kinase activated form of phosphatidylinositol-3-kinase

The human high affinity receptor for immunoglobulin G, FcγRI, in dibutyryl cyclic AMP (dbcAMP)-differentiated U937 cells, is coupled to the activation of phospholipase C (PLC) and the conventional protein kinase C (PKC) isoforms, α, β, and γ. Here we demonstrate that aggregation of FcγRI activates the tyrosine-kinase regulated form of phosphatidylinositol-3-kinase (PI-3-kinase) and that an increase of phosphatidylinositol trisphosphate (PIP3) is essential for the activation and translocation of PLCγ1 in these cells. In addition, activation of the PKC isoforms was ablated by specific inhibitors of PI3-kinase or by overexpression of a dominant negative p85 subunit of PI3-kinase. The findings reported here demonstrate that PLCγ1 and PKC activation by FcγRI are downstream of PI3-kinase, and that in contrast to cytokine primed cells, only the tyrosine-kinase activated isoform of PI3-kinase is coupled to FcγRI in dbcAMP-differentiated cells

Paramentação cirúrgica: avaliação de sua adequação para a prevenção de riscos biológicos em cirurgias - parte II: os componentes da paramentação Surgical scrub: evaluating its adequation for preventing Biological risks in surgeries. part II: the components of the surgical scrub

O estudo elaborou critérios de avaliação dos componentes da paramentação cirúrgica de hospitais do município de São Paulo. A maior dificuldade nessa elaboração deveu-se à inexistência de normas e consenso sobre a porosidade dos tecidos como barreira microbiológica e de contato com sangue e outros fluidos. Contudo, foi possível reconhecer aspectos positivos e problemáticos. Observou-se que existe semelhanças dos componentes entre os hospitais, no que se refere a modelo e tipo de tecido. As luvas foram os componentes com maior índice de adequação e os propés, os de maior índice de inadequação. O aspecto mais problemático referiu-se aos controles de aquisição e de reprocessamento dos componentes re-utilizáveis.<br>The study elaborated evaluation patterns of the components of the surgical scrub in hospitals of the district of São Paulo. The most important difficulty was the lack of rules and consent on the types of the fabrics, as a microbiological and contact with blood and other fluids barrier. However, it was possible to identify positive and problematic aspects. It was observed that the components are similar among the hospitals, considering the design and the way of fabrics production. Gloves were the ones with the best quality results, while shootweares were the worst. The most problematic aspect was referred to the acquisition controls and the re-use process of the components

HIV Risk Among Men Who Have Sex With Men, Women Who Have Sex With Women, Lesbian, Gay, Bisexual and Transgender Populations in South Africa: A Mini-Review

BACKGROUND: The HIV epidemic in South Africa is characterized mainly by heterosexual transmission. Recently, the importance of targeting key populations and marginalized groups, including men who have sex with men (MSM) and transgender people, has been added to the national agenda. OBJECTIVES: This mini-review explores the current state of empirical research on HIV risk and MSM, women who have sex with women (WSW), lesbian, gay, bisexual and transgender (LGBT) populations in South Africa in order to assess the current state of research and identify gaps in the literature. METHOD: Peer-reviewed empirical social and behavioral articles on HIV prevalence and risk focusing on MSM, WSW, and LGBT populations published since 2006 were included in this mini-review. RESULTS: In total 35 articles were included: 30 on MSM, gay, and/or bisexual male-identified populations, three on WSW, lesbian, and/or bisexual female-identified populations, two on LGB youth, and none on transgender populations. CONCLUSION: Despite South Africa being the country with the largest number of people living with HIV in the world, there is a limited amount of research in South Africa on HIV and non-normative gender identities and sexualities, especially WSW, lesbian, and/or bisexual female-identified populations, transgender populations, and LGB youth. Research with MSM, WSW, and LGBT populations should be prioritized in South Africa in order to appropriately inform HIV prevention strategies that meet the specific needs of these marginalized groups