Induction by leptin of uncoupling protein-2 and enzymes of fatty acid oxidation

We have studied mechanisms by which leptin overexpression, which reduces body weight via anorexic and thermogenic actions, induces triglyceride depletion in adipocytes and nonadipocytes. Here we show that leptin alters in pancreatic islets the mRNA of the genes encoding enzymes of free fatty acid metabolism and uncoupling protein-2 (UCP-2). In animals infused with a recombinant adenovirus containing the leptin cDNA, the levels of mRNAs encoding enzymes of mitochondrial and peroxisomal oxidation rose 2- to 3-fold, whereas mRNA encoding an enzyme of esterification declined in islets from hyperleptinemic rats. Islet UCP-2 mRNA rose 6-fold. All in vivo changes occurred in vitro in normal islets cultured with recombinant leptin, indicating direct extraneural effects. Leptin overexpression increased UCP-2 mRNA by more than 10-fold in epididymal, retroperitoneal, and subcutaneous fat tissue of normal, but not of leptin-receptor-defective obese rats. By directly regulating the expression of enzymes of free fatty acid metabolism and of UCP-2, leptin controls intracellular triglyceride content of certain nonadipocytes, as well as adipocytes.     

Supplementary anti-hepatitis C virus (HCV) testing with 2nd and 3rd generation recombinant immunoblot assay and matrix applied to enzyme immunoassay positive sera and comparison with HCV-RNA detection

Following the same general principles of its two predecessors in 1973 and 1986, the 1996 National Roadside Survey of weekend, nighttime drivers in the 48 contiguous states interviewed and breath tested over 6000 noncommercial four-wheel vehicle operators between September 6 and November 9, 1996. Results indicated that the total number of drinking drivers fell by about one-third between 1986 and 1996; however, there was no significant change in the number of drivers at blood alcohol concentrations (BACs) at or above 0.05. Compared to 1973, the proportion of women drivers on the roads during weekend nights has increased significantly. Moreover, relative to males, the proportion of female drivers who have been drinking has increased over the last decade. The number of drivers under the age of 21 with a BAC at or above 0.10 decreased significantly from 1986 to 1996.     

Effects of age, sex, and ethnicity on the association between apolipoprotein E genotype and Alzheimer disease. A meta-analysis. APOE and Alzheimer Disease Meta Analysis Consortium

OBJECTIVE: To examine more closely the association between apolipoprotein E (APOE) genotype and Alzheimer disease (AD) by age and sex in populations of various ethnic and racial denominations. DATA SOURCES: Forty research teams contributed data on APOE genotype, sex, age at disease onset, and ethnic background for 5930 patients who met criteria for probable or definite AD and 8607 controls without dementia who were recruited from clinical, community, and brain bank sources. MAIN OUTCOME MEASURES: Odds ratios (ORs) and 95% confidence intervals (CIs) for AD, adjusted for age and study and stratified by major ethnic group (Caucasian, African American, Hispanic, and Japanese) and source, were computed for APOE genotypes epsilon2/epsilon2, epsilon2/epsilon3, epsilon2/epsilon4, epsilon3/epsilon4, and epsilon4/epsilon4 relative to the epsilon3/epsilon3 group. The influence of age and sex on the OR for each genotype was assessed using logistic regression procedures. RESULTS: Among Caucasian subjects from clinic- or autopsy-based studies, the risk of AD was significantly increased for people with genotypes epsilon2/epsilon4 (OR=2.6, 95% CI=1.6-4.0), epsilon3/epsilon4 (OR=3.2, 95% CI=2.8-3.8), and epsilon4/epsilon4 (OR=14.9, 95% CI= 10.8-20.6); whereas, the ORs were decreased for people with genotypes epsilon2/epsilon2 (OR=0.6, 95% CI=0.2-2.0) and epsilon2/epsilon3 (OR=0.6, 95% CI=0.5-0.8). The APOE epsilon4-AD association was weaker among African Americans and Hispanics, but there was significant heterogeneity in ORs among studies of African Americans (P<.03). The APOE epsilon4-AD association in Japanese subjects was stronger than in Caucasian subjects (epsilon3/epsilon4: OR=5.6, 95% CI=3.9-8.0; epsilon4/epsilon4: OR=33.1, 95% CI=13.6-80.5). The epsilon2/epsilon3 genotype appears equally protective across ethnic groups. We also found that among Caucasians, APOE genotype distributions are similar in groups of patients with AD whose diagnoses were determined clinically or by autopsy. In addition, we found that the APOE epsilon4 effect is evident at all ages between 40 and 90 years but diminishes after age 70 years and that the risk of AD associated with a given genotype varies with sex. CONCLUSIONS: The APOE epsilon4 allele represents a major risk factor for AD in all ethnic groups studied, across all ages between 40 and 90 years, and in both men and women. The association between APOE epsilon4 and AD in African Americans requires clarification, and the attenuated effect of APOE epsilon4 in Hispanics should be investigated further.     

Magnetic resonance imaging of the pelvic floor in patients with obstructed defaecation

BACKGROUND: Evacuation proctography and measurements of anorectal physiology are frequently used to clarify the pathophysiology of obstructed defaecation. In some patients these tests are normal, despite convincing clinical evidence of defaecatory difficulty. The aim of this study was to determine whether magnetic resonance imaging (MRI) could reveal pelvic floor abnormality in patients with obstructed defaecation. METHODS: Eleven women with obstructed defaecation, in whom evacuation proctography and anorectal physiology were normal, were examined by MRI, using a fast gradient echo sequence. Measurements of pelvic visceral and muscular descent were taken at rest and during straining, and compared with those obtained from 13 asymptomatic volunteers. RESULTS: Patients with obstructed defaecation had significantly greater pelvic visceral descent (P < 0.05), levator muscle descent (P = 0.04), levator plate angle change (P = 0.003) and increase in the area of the pelvic floor hiatus (P = 0.0002) than asymptomatic volunteers. CONCLUSION: MRI demonstrated marked pelvic visceral and levator muscle descent in women with obstructed defaecation, despite normal evacuation proctography and anorectal physiology. MRI should be considered if these examinations have been normal.     

Midline dorsal appendages

A case of a mature posterior cervical teratoma resembling two fingers and a case of a lumbosacral limb are presented. These are at least the seventh and eighth reported paraspinous or occipital teratomas with recognizable extremity development. Both anomalies had intradural extension and required exploration to decrease the likelihood of future spinal cord tethering. Preoperative evaluation, surgical technique, postoperative follow-up, and review of the literature are presented.     

Update: cancer screening in women

Current cancer screening recommendations for women have been reviewed. Controversies have been identified. Many additional references are available upon request.     

mRNA and cytoskeletal filaments

There is evidence that low birth weight and poor growth in early life cause a long-term predisposition to non-insulin-dependent diabetes. Morphological changes were assessed in fetal rat pancreas subjected to both pre- and post-natal maternal protein deprivation (LP). Further groups were subjected to purely prenatal maternal protein deprivation (preLP) and purely postnatal maternal protein deprivation (postLP), as well as a control group. The results show that the LP and postLP groups had fewer but larger islets than the control group, while the preLP group had more numerous, smaller islets. All three low protein groups had more irregularly shaped islets than the control group. There was a reduction in the amount of beta cells within each islet in all three protein-deprived groups. The LP and postLP groups showed a reduction in the percentage of islet tissue and beta cells per pancreas, but the percentage of islet tissue expressed per unit body weight was similar in all four groups. These results show that in maternal protein deprivation, homeostatic mechanisms ensure a constant amount of pancreatic endocrine tissue per unit of body weight. However, there remain major structural changes in the size, shape, and composition of the islets. These results support the theory that early development profoundly affects the structure of the pancreas and may play a role in the later development of adult diseases, such as non-insulin-dependent diabetes mellitus.     

Bixin and norbixin in human plasma: determination and study of the absorption of a single dose of Annatto food color

A procedure was developed for the detection and determination of bixin and norbixin in human plasma by reversed-phase HPLC with a sensitivity limit of 5 micrograms l-1. A group of seven volunteers ingested a single dose of 1 ml of a commercial Annatto Food Color (16 mg of cis-bixin in soybean oil). The presence of bixin (cis and trans) and norbixin (cis and trans) was demonstrated in the plasma at average levels of 11.6, 10.1, 2.8 and 0 micrograms l-1 of bixin and 48, 58, 53 and 29 micrograms l-1 of norbixin after 2, 4, 6 and 8 h, respectively. Considerable individual variations were observed. Complete plasma clearance generally occurred for bixin by 8 h and for norbixin by 24 h after ingestion of cis-bixin.