Biomedical subjects

T Haas

Publications and source records attributed to T Haas.

111 records · Page 7Linked to original sources

PubMedDate not supplied

The influence of short-term fasting on serum leptin levels, and selected hormonal and metabolic parameters in morbidly obese and lean females.

The aim of our study was to compare the changes of serum leptin levels after 24-h fasting in morbidly obese and lean females and to search for hormonal and metabolic factors responsible for the changes in serum leptin levels. Fourteen morbidly obese and twelve lean females were included in the study. The blood for leptin, insulin, cortisol, blood glucose (BG), beta-OH-butyrate (beta-OH), dehydroepiandrosterone (DHEA) and DHEA-sulphate (DHEA-S) measurements was withdrawn before and after a 24-h fast. Basal body mass index (BMI), serum leptin, insulin and beta-OH levels were significantly higher in the obese compared to the lean group. The 24-h fasting decreased significantly BMI, serum leptin (by 20% in obese vs. 62% in lean subjects), insulin (by 23.3% in obese vs. 23.1% in lean subjects) and increased beta-OH (by 36% in obese vs. 1300% in lean subjects). Basal serum leptin levels correlated positively with BMI in both groups and with insulin levels in the obese group. The multiple regression analysis using delta leptin as dependent and the basal values of the rest of studied parameters as independent variables revealed that in lean subjects serum cortisol together with DHEA-S and BMI accounted for 71% of variations of the change of serum leptin levels (delta leptin = 0.31- 0.0101 cortisol + 0.0012 DHEA-S + 0.37 BMI). In obese subjects the 43.9% of variations of the change of serum leptin levels was explained by BMI together with age and DHEA-S levels (delta leptin = 36.09 + 0.35 BMI - 0.717 age- 0.008 DHEA-S). The drop of serum leptin levels after 24-h starvation is significantly blunted in obese compared to lean subjects. The reason for the difference is probably the insulin resistance possibly further modified by different DHEA-S levels.

3-Hydroxybutyric Acid↗

PubMedDate not supplied

Contraceptive failure rates: new estimates from the 1995 National Survey of Family Growth.

CONTEXT: Unintended pregnancy remains a major public health concern in the United States. Information on pregnancy rates among contraceptive users is needed to guide medical professionals' recommendations and individuals' choices of contraceptive methods. METHODS: Data were taken from the 1995 National Survey of Family Growth (NSFG) and the 1994-1995 Abortion Patient Survey (APS). Hazards models were used to estimate method-specific contraceptive failure rates during the first six months and during the first year of contraceptive use for all U.S. women. In addition, rates were corrected to take into account the underreporting of induced abortion in the NSFG. Corrected 12-month failure rates were also estimated for subgroups of women by age, union status, poverty level, race or ethnicity, and religion. RESULTS: When contraceptive methods are ranked by effectiveness over the first 12 months of use (corrected for abortion underreporting), the implant and injectables have the lowest failure rates (2-3%), followed by the pill (8%), the diaphragm and the cervical cap (12%), the male condom (14%), periodic abstinence (21%), withdrawal (24%) and spermicides (26%). In general, failure rates are highest among cohabiting and other unmarried women, among those with an annual family income below 200% of the federal poverty level, among black and Hispanic women, among adolescents and among women in their 20s. For example, adolescent women who are not married but are cohabiting experience a failure rate of about 31% in the first year of contraceptive use, while the 12-month failure rate among married women aged 30 and older is only 7%. Black women have a contraceptive failure rate of about 19%, and this rate does not vary by family income; in contrast, overall 12-month rates are lower among Hispanic women (15%) and white women (10%), but vary by income, with poorer women having substantially greater failure rates than more affluent women. CONCLUSIONS: Levels of contraceptive failure vary widely by method, as well as by personal and background characteristics. Income's strong influence on contraceptive failure suggests that access barriers and the general disadvantage associated with poverty seriously impede effective contraceptive practice in the United States.

Abortion, Induced↗

PubMedDate not supplied

A clinical measure of the posterior epidural space depth.

BACKGROUND AND OBJECTIVES: The object of this study was to measure the clinically relevant depth of the posterior epidural space (ES) while placing subarachnoid catheters. METHODS: "Hanging drop" technique was used to locate the ES via a midline approach in the lumbar area. The distance from the skin to the ES was measured, and the needle was advanced until free flow of cerebrospinal fluid was observed. The distance between entry into the ES and the subarachnoid space-the posterior ES depth-was then measured. Regression analysis was used to investigate relationships between skin-to-ES distance, posterior ES depth, and patient characteristics (height, weight, body surface area [BSA] and age). RESULTS: The 55 patients studied had a mean skin-to-ES distance of 50.9 +/- 12 mm (range, 27-94) and a mean posterior ES depth of 6.9 +/- 4 mm (range 2-25). Skin-to-ES distance was related to BSA (r = .597, P < .0001) and weight (r = .572 P < .0001). No correlation was found between posterior ES depth and any other variable. CONCLUSIONS: The posterior ES has been found to be somewhat larger and more variable than previously described. The findings provide clinical confirmation of recent radiologic and cadaveric studies, which portray a posterior ES of variable size and complex shape. These findings have implications for cannulation and use of epidural therapy as well as for the combined catheter epidural and single-dose spinal technique.

Adult↗