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.

Mutations in the pre-core region of hepatitis B virus serve to enhance the stability of the secondary structure of the pre-genome encapsidation signal.

Abstract: We conducted a large-scale survey to determine the frequency and clinical significance of mutations in the pre-core region of hepatitis B virus (HBV). Sera from 263 patients with chronic HBV infection were analyzed by direct sequencing of PCR-amplified HBV DNA. Four major missense/nonsense mutations (M) were found: (M1) C-->T at nucleotide position 1856, Pro-->Ser at codon 15; (M2) G-->A at position 1896, Trp-->stop at codon 28; (M3) G-->A at position 1898, Gly-->Ser at codon 29; and (M4) G-->A at position 1899, Gly-->Asp at codon 29. The commonest conserved mutation was M0: T-->C at position 1858, Pro-->Pro at codon 15. We found that M1 and M2 were mutually exclusive, M3 was only found in association with M1, and M4 was predominantly found in association with M2. All patients with M1 but none of those with M2 had M0. The invariable coexistence of certain mutations in codon 15 and codons 28 and 29 and the mutual exclusion of other mutations in these two noncontiguous regions is related to the stem-loop structure of the pre-genome encapsidation sequence located in the precore/core region. M2 and M4 enhance the stability of the stem by providing two additional paired sites. M1 destroys an existing base pair. However, M1 only occurred in the presence of M0, which provides an extra paired site, and 50% of patients with M1 had M3, a compensatory mutation that restores base pairing at this site. Our data support the proposed secondary structure of the pre-genome encapsidation sequence. The primary function of the mutations in the pre-core region is to enhance stability of this secondary structure to ensure perpetuation of viral replication.

Meta-analysis identifies common variants associated with body mass index in east Asians

Abstract: Multiple genetic loci associated with obesity or body mass index (BMI) have been identified through genome-wide association studies conducted predominantly in populations of European ancestry We performed a meta-analysis of associations between BMI and approximately 24 million SNPs in 27,715 east Asians, which was followed by in silico and de novo replication studies in 37,691 and 17,642 additional east Asians, respectively We identified ten BMI-associated loci at genome-wide significance (P < 50 × 10(-8)), including seven previously identified loci (FTO, SEC16B, MC4R, GIPR-QPCTL, ADCY3-DNAJC27, BDNF and MAP2K5) and three novel loci in or near the CDKAL1, PCSK1 and GP2 genes Three additional loci nearly reached the genome-wide significance threshold, including two previously identified loci in the GNPDA2 and TFAP2B genes and a newly identified signal near PAX6, all of which were associated with BMI with P < 50 × 10(-7) Findings from this study may shed light on new pathways involved in obesity and demonstrate the value of conducting genetic studies in non-European populations

Hypoglycemia, Diabetes, and Cardiovascular Events

Abstract: Diabetes is at epidemic proportions in the U.S. Patients with diabetes are at increased risk for micro- and macrovascular complications. The benefit of glycemic control in decreasing the risk for microvascular disease is well established. However, the role of glycemic control in decreasing macrovascular complications has been controversial. Several large clinical trials looking at this issue have either shown no benefit or even potential harm. The possibility of hypoglycemia as a risk factor for cardiovascular events is a topic of much debate. In this review article, we discuss the evidence for and against this hypothesis and the possible mechanisms that might be involved. Patients with diabetes have an increased risk of cardiovascular disease. The link between glycemic control and microvascular complications has been firmly established (1,2). However, the association between glycemic control and macrovascular disease is mainly obtained from epidemiological studies, and intensive glucose control has often failed to reduce macrovascular events. Intensive glucose control invariably increases the risk of hypoglycemia and sometimes the severity of hypoglycemia (2) Several epidemiological studies and smaller prospective studies have linked hypoglycemia to increased cardiovascular risk (3⇓–5). Recent large randomized trials looking at intensive glycemic control have either shown no benefit (Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation [ADVANCE] and Veterans Affairs Diabetes Trial [VADT]) or increased all cause mortality (Action to Control Cardiovascular Risk in Diabetes [ACCORD]) (6). While the reason for the increased mortality is unclear and hypoglycemia has not been implicated as a cause of death, these studies have increased the debate about the degree of glycemic control required to decrease diabetes complications and the role of hypoglycemia in cardiovascular morbidity and mortality. The modern definition of hypoglycemia is plasma glucose <70 mg/dl (7⇓–9). At plasma glucose …

Childhood risk factors predict adult risk associated with subclinical cardiovascular disease ☆: The Bogalusa Heart Study

Abstract: Cardiovascular risk factors begin in childhood and are predictive of cardiovascular risk in adulthood. Observations in the Bogalusa Heart Study have shown an important correlation of clinical risk factors in early life with anatomic changes in the aorta and coronary vessels with atherosclerosis and cardiac and renal changes related to hypertension. These observations have been extended by echo Doppler studies of carotid artery intima media thickness (IMT). A close association of risk factors in young adults, 20-38 years of age, occurs with IMT, and a marked increase is noted as numbers of risk factors increase. More extensive changes seem to occur in the bulb or bifurcation area. This area may be an earlier marker of disease. Observations of risk factors in young individuals and noninvasive studies of structural changes of the cardiovascular system have strong implications for prevention by cardiologists.

Cross-level effects of demography and diversity climate on organizational attachment and firm effectiveness

Abstract: We studied the impact of demographic diversity on individual attachment and firm unit performance in a relatively diverse organization. We implemented cross-level regression to study gender and race/ethnic categorical, relational, and organizational demography in a sample of 26 units part of a regional restaurant chain. At the individual level, we found that diversity climate (DC) moderates the impact of relational and categorical demography on affective organizational commitment, organizational identification, and intention to quit. At the organizational level, we found that DC moderates the impact of organizational diversity on firm productivity and return on profit. We discuss the importance of organizational DC as organizational context on individual attachment, and implications for firm effectiveness in diverse organizations. Copyright © 2007 John Wiley & Sons, Ltd.