Tulane University

About: Tulane University is a education organization based out in New Orleans, Louisiana, United States. It is known for research contribution in the topics: Population & Blood pressure. The organization has 24478 authors who have published 47205 publications receiving 1944993 citations. The organization is also known as: University of Louisiana.

Protein-tyrosine Phosphatase-1B acts as a negative regulator of insulin signal transduction

Abstract: Insulin signaling involves a dynamic cascade of protein tyrosine phosphorylation and dephosphorylation. Most of our understanding of this process comes from studies focusing on tyrosine kinases, which are signal activators. Our knowledge of the role of protein-tyrosine phosphatases (PTPases), signal attenuators, in regulating insulin signal transduction remains rather limited. Protein-tyrosine phosphatase 1B (PTP-1B), the prototypical PTPase, is ubiquitously and abundantly expressed. Work from several laboratories, including our own, has implicated PTP-1B as a negative regulator of insulin action and as a potentially important mediator in the pathogenesis of insulin-resistance and non-insulin dependent diabetes mellitus (NIDDM).

MicroRNA-155 Is an Epstein-Barr Virus-Induced Gene That Modulates Epstein-Barr Virus-Regulated Gene Expression Pathways

Abstract: The cellular microRNA miR-155 has been shown to be involved in lymphocyte activation and is expressed in Epstein-Barr virus (EBV)-infected cells displaying type III latency gene expression but not type I latency gene expression. We show here that the elevated levels of miR-155 in type III latency cells is due to EBV gene expression and not epigenetic differences in cell lines tested, and we show that expression in EBV-infected cells requires a conserved AP-1 element in the miR-155 promoter. Gene expression analysis was carried out in a type I latency cell line transduced with an miR-155-expressing retrovirus. This analysis identified both miR-155-suppressed and -induced cellular mRNAs and suggested that in addition to direct targeting of 3′ untranslated regions (UTRs), miR-155 alters gene expression in part through the alteration of signal transduction pathways. 3′ UTR reporter analysis of predicted miR-155 target genes identified the transcriptional regulatory genes encoding BACH1, ZIC3, HIVEP2, CEBPB, ZNF652, ARID2, and SMAD5 as miR-155 targets. Western blot analysis of the most highly suppressed of these, BACH1, showed lower expression in cells transduced with a miR-155 retrovirus. Inspection of the promoters from genes regulated in EBV-infected cells and in cells infected with an miR-155 retrovirus identified potential binding sequences for BACH1 and ZIC3. Together, these experiments suggest that the induction of miR-155 by EBV contributes to EBV-mediated signaling in part through the modulation of transcriptional regulatory factors.

Continued decline in blood lead levels among adults in the United States: The national health and nutrition examination surveys

Abstract: Background Declines in blood lead levels between 1976 and 1991 among US adults have been previously reported. More recent trends in blood lead levels and the association of lower blood lead levels with chronic disease have not been reported. Methods Data from 2 nationally representative cross-sectional surveys, the Third National Health and Nutrition Examination Survey conducted in 1988-1994 (n = 16 609) and the National Health and Nutrition Examination Survey conducted in 1999-2002 (n = 9961) were analyzed. Results The geometric mean blood lead level declined 41% from 2.76 μg/dL (0.13 μmol/L) in 1988-1994 to 1.64 μg/dL (0.08 μmol/L) in 1999-2002. The percentage of adults with blood lead levels of 10 μg/dL (0.48 μmol/L) or higher declined from 3.3% in 1988-1994 to 0.7% in 1999-2002 ( P Conclusions Blood lead levels continue to decline among US adults, but racial and ethnic disparities persist. Higher blood lead levels remain associated with a higher burden of chronic kidney and peripheral arterial diseases among the overall population and with hypertension among non-Hispanic blacks and Mexican Americans.