Usefulness of visceral obesity (waist/hip ratio) in predicting vascular endothelial function in healthy overweight adults

Vascular endothelial dysfunction (VED) is associated with obesity; however, its etiology remains controversial. By determining the predictors of fasting and postprandial endothelial function in overweight adults without other cardiovascular risk factors, we were able to investigate novel mechanisms directly linking obesity to VED. Thirty-two healthy adults (body mass index [BMI] > or =27 kg/m(2)) underwent determination of fasting low-density lipoprotein (LDL) particle size, high sensitivity C-reactive protein levels, anthropometric measurements, and endothelial function by flow-mediated dilation (FMD) of the brachial artery. Postprandial lipemia and FMD were measured 4 hours after ingestion of a high-fat meal. Blood pressures and fasting levels of lipoproteins, glucose, insulin, and fatty acids were within normal limits in all subjects. An abdominal fat pattern, as determined by an increased waist/hip ratio (WHR), was the sole significant predictor of FMD (r = -0.58, p = 0.001), despite no significant correlation between whole body obesity (BMI) and FMD. At comparable levels of BMI, obese subjects with a WHR > or =0.85 had a significantly blunted FMD compared with those with a WHR <0.85 (3.93 +/- 2.85% vs 8.34 +/- 5.47%, p = 0.016). Traditional coronary risk factors, C-reactive protein, postprandial lipemia, and LDL particle size did not predict FMD. We found no appreciable alteration in the postprandial state from fasting FMD (6.31 +/- 4.62% vs 6.25 +/- 5.47%, p = 0.95). The same results were found when women were analyzed alone. Increased abdominal adiposity determined by a simple WHR is a strong independent predictor of VED even in healthy overweight adults; this is a finding unexplained by alterations in conventional risk factors, systemic inflammation, or the atherogenic lipoprotein pattern.

New graphical method for evaluating gas exchange in congestive heart failure

PURPOSE

The purpose of this study was to determine the usefulness of a new graphical method for evaluating gas exchange (GE), as applied to three common averaging techniques used during rest, exercise, and recovery in patients with congestive heart failure (CHF).

METHODS

Fifty patients' resting, exercise, and recovery GE graphs were evaluated using a new graphical method to determine oxygen consumption (VO2), ventilation (VE), and respiratory exchange ratio (RER). Precision of the new method was evaluated by repeated measures using the same investigator, an additional investigator, and an untrained student. A 1-min rolling time average (RTA) updated every 20 s was used as the reference to the graphical method and the metabolic cart's computer analysis. Breath-by-breath data were evaluated using three averaging techniques, average 5 of 7 breaths (5/7), average of 8 breaths (AVG 8), and 30-s average (30-s). Differences between the computer and the graphical method were assessed by two-sided t-tests; ANOVA was used between the three investigators and also between the three averaging techniques.

RESULTS

There were no significant differences of repeated measures between trained and untrained investigators. The graphical method results were significantly different than the computer results. The only difference with RTA involved computer resting values, which were also different than the graphical method.

CONCLUSION

In conclusion, the graphical method may be used to standardize GE evaluation because it displays excellent intrainvestigator precision and good interinvestigator precision between experienced and inexperienced investigators. Averaging techniques less than 30 s have greater bias when using computer-derived values, although when incorporating the graphical method the averaging technique chosen has little influence on all measures.

Evaluation of lipid profile measurements obtained from the Cholestech L.D.X analyzer

BACKGROUND

The Cholestech L.D.X analyzer has the capability of performing a lipid profile in approximately 5 minutes. The purpose of this study was to determine analytical performance capability of the L.D.X to perform lipid profile measurements.

METHODS

Forty subjects gave two finger capillary samples and one venous serum which were analyzed in duplicate by two technicians, on two different L.D.X analyzers. A local pathology laboratory was used as the standard for accuracy comparisons. Two controls with known values were provided by the manufacturer to assess within-day precision. Day-to-day precision was determined by analyzing high (240 mg/dL-1 total cholesterol (TC) and 60 mg/dL-1 high-density lipoprotein [HDL]) and low (200 mg/dL-1 TC and 35 mg/dL-1 HDL) human serum samples on 10 different days.

RESULTS

Analysis of variance procedures revealed no significant differences between the two technicians or the two analyzers, nor among the fingerstick, venous serum, or reference measures for any of the analytes. The total error of measurement of TC, triglycerides, and HDL measurements were 6.3 to 16.2%, 14.8 to 30.8%, and 11.5 to 26.8%, respectively. In comparison to the National Cholesterol Education Program (NCEP) desirable, borderline-high, and high classifications obtained from the reference laboratory the L.D.X TC results were correctly classified in 92.5% of the cases. L.D.X triglyceride classifications of desirable, borderline hypertyglyceridemia, and distinct hypertriglyceridemia matched 100% with the classifications obtained from the reference laboratory.

CONCLUSIONS

Although the Cholestech L.D.X analyzer did not consistently meet NCEP standards for acceptable total measurement error of TC, HDL, and triglyceride analyses, it seems capable of providing reasonable lipid profile measures in both a screening setting and a clinician office where the goal is correct classification of patients' results.

Further commentary on Fox's "In the Matter of 'Baby M'"

Modern science has made it easy for fertile women to become pregnant by artificial insemination. And childless couples have been able to find women willing, for a fee, to accept insemination by a prospective father and agree to transfer custody of the resulting child to the father. Enterprises designed to match willing mothers and sperm-donating fathers have established themselves. The central public policy dilemma raised by this union of technology and the ancient desire for issue of one's own loins—is it wiser for the legal system to provide its normal protections to the participants in surrogacy arrangements or withdraw from the field—was brought to national attention by the Baby M case.

Fibroleiomyomatous hamartoma of the lung

Fibroleiomyomatous hamartoma of the lung is an extremely rare, nonneoplastic overgrowth of pulmonary muscle tissue which can be found in various sites throughout the lung. Several cases have been previously described. The case presently reviewed demonstrates the multinodular form of this entity. Fibroleiomyomatous hamartoma may also appear as a solitary coin lesion or as a diffuse interstitial pattern on chest radiographs.

Real time ophthalmic ultrasonography

Material from three years of experience with a real time contact ophthalmic scanner is presented. Routine screening of patients with cataracts revealed unsuspected retinal detachments and advanced vitreous hemorrhage in a significant percentage. Foreign bodies near the posterior ocular wall were optimally evaluated by both radiographic and ultrasonic localization methods to avoid the inherent error of the x-ray triangulation system. The traumatized eye may be effectively studied for internal damage by using a thick layer of methyl cellulose without putting pressure on the globe. Many types of vitreous and retinal pathology may be confirmed or better evaluated by this simple, noninvasive technique.