Sex and insulin sensitivity

To analyze whether enhanced adiposity in females as compared with males is associated with a decreased sensitivity to insulin, a group of healthy normal weight females (n = 13, age 21 ± 1 years) and males (n = 11, age 23 ± 1 year, mean ± SEM) was studied. In each subject, body composition (% fat and % muscle), maximal aerobic power (V_O2 max) and whole body insulin-mediated glucose metabolism were measured. The group of women had a higher percentage of fat to total body weight (P < 0.001) and a lower percentage of muscle (P < 0.001) than the group of men. The higher percentage of fat in women compared with males was due to enhanced peripheral fat accumulation in the arm and thigh regions. V_O2 max levels were comparable in both groups (48 ± 1 mL/kg/min for women, 53 ± 2 mL/kg/min for men, P = NS). The rate of glucose metabolism (M) was comparable in women (8.78 ± 0.74 mg/kg/min), and men (8.31 ± 0.89 mg/kg/min) when expressed per kilogram of total body weight, but when expressed per kilogram of muscle tissue (M_m), it was 45% higher in women (29.4 ± 2.4 mg/kg/min) than in men (20.2 ± 1.6 mg/kg/min, P < 0.005). Partial correlation analysis indicated that the percentage of fat was inversely related to M and M_m in both women (P < 0.05) and men (P < 0.05), but not to percentage of muscle or V_O2 max. Conclusions: (1) Insulin-mediated glucose disposal is inversely related to adiposity in normal weight healthy males and females. (2) Women and men utilize equal amounts of glucose despite a higher adiposity in females. (3) Since muscle tissue utilizes most of intravenously administered glucose, this result indicates enhanced glucose uptake by muscle tissue in females compared with males. (4) Elevated glucose uptake by muscle in women may provide a mechanism by which women are protected against excessive hyperglycemia despite their smaller amount of glucose-consuming tissue.     

Fatty liver: a novel component of the metabolic syndrome

Although the epidemic of obesity has been accompanied by an increase in the prevalence of the metabolic syndrome, not all obese develop the syndrome and even lean individuals can be insulin resistant. Both lean and obese insulin resistant individuals have an excess of fat in the liver which is not attributable to alcohol or other known causes of liver disease, a condition defined as nonalcoholic fatty liver disease (NAFLD) by gastroenterologists. The fatty liver is insulin resistant. Liver fat is highly significantly and linearly correlated with all components of the metabolic syndrome independent of obesity. Overproduction of glucose, VLDL, CRP, and coagulation factors by the fatty liver could contribute to the excess risk of cardiovascular disease associated with the metabolic syndrome and NAFLD. Both of the latter conditions also increase the risk of type 2 diabetes and advanced liver disease. The reason why some deposit fat in the liver whereas others do not is poorly understood. Individuals with a fatty liver are more likely to have excess intraabdominal fat and inflammatory changes in adipose tissue. Intervention studies have shown that liver fat can be decreased by weight loss, PPARgamma agonists, and insulin therapy.     

Functional impairment in spondyloarthropathy and fibromyalgia

OBJECTIVE: To compare the functional ability of patients with spondyloarthropathy (SpA) and fibromyalgia (FM) using the Bath Ankylosing Spondylitis Functional Index (BASFI), the Dougados Functional Index (DFI), and and the Health Assessment Questionnaire for Spondyloarthropathy (HAQ-S), to establish whether these indicators can differentiate between these patient groups, and to ascertain how well the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) functions in patients with FM. METHODS: Twenty-four patients with SpA and 70 with FM, all female, filled in 4 self-administered questionnaires: BASFI, DFI, HAQ-S, and the BASDAI; results were compared between the 2 groups. RESULTS: The decline in functional ability was similar in patients with SpA and FM when assessed by BASFI, but slightly greater in the SpA group when assessed by DFI and HAQ-S. BASDAI was significantly (p = 0.018) greater in the FM group. CONCLUSION: An almost similar functional decline was observed in both SpA and FM patients when measured by the indices developed for patients with AS and SpA. The specificity of BASDAI in measuring disease activity in SpA was poor, as disease activity in FM was rated higher than in SpA.     

Magnetic Resonance Imaging Angiography in Patency Evaluation of Bronchial Artery Revascularization Grafts

In this report we present our experience of non-invasive magnetic resonance imaging (MR) angiography and selective catheter angiography in assessing the patency of bronchial artery revascularization grafts after an en bloc double-lung and heart-lung transplantation. We studied 8 patients who had undergone pulmonary transplantation with direct bronchial artery revascularization. Catheter angiography was performed 10 days to 63 months postoperatively. MR angiography was performed within 24 h of the catheter procedure and the results were compared with the findings from catheter angiography. Catheter angiography showed the bronchial revascularization graft to be patent in 6 patients and occluded in 2. At MR angiography, the patency of bronchial artery revascularization grafts was reliably identified in 7 of the 8 patients. One patient had inadequate image quality because of void artefacts caused by haemostatic clips. It is concluded that MR angiography is a reliable method for assessing the patency of bronchial artery revascularization grafts.     

Bronchial Artery Revascularization Improves Tracheal Anastomotic Healing after Lung Transplantation

The study aimed to clarify the role of direct bronchial artery revascularization (BAR) after en bloc double-lung (DLT) and heart-lung transplantation (HLT). Group I comprised eight patients with en bloc DLT or HLT and successful BAR, while group II included 14 DLT or HLT cases without BAR or with failed BAR. From these groups, 2 subgroups were extracted: group III, including 6 cases of en bloc DLT with successful BAR and group IV 10 HLT cases without or with failed BAR. Airway healing was evaluated at bronchoscopy and patency of BAR with angiography. Pulmonary viral, bacterial and fungal infections, rejections and bronchiolitis obliterans syndrome (BOS) were registered. Tracheal healing at 2 weeks and 3 months was better in group I than in group II (p = 0.003 and p = 0.05, respectively). Compared with group IV, tracheal anastomotic healing at 2 weeks was better in group III (p = 0.007) and tended to be better also after 3 months (p = 0.07). The incidence of infections, rejection or BOS did not differ between groups I and II. BAR thus improved healing of tracheal anastomosis.     

Exclusion of coronary artery disease by exercise thallium-201 tomography in patients with aortic valve stenosis.

In many patients with valvular aortic stenosis (AS), management decisions may be possible without invasive studies if coexistent coronary artery disease (CAD) can be ruled out noninvasively. The use of thallium-201 single-photon emission computed tomography to the exclusion of CAD was studied in 44 patients aged 41 to 78 years with AS. In addition to cardiac catheterization and selective coronary angiography, patients underwent a cardiac ultrasound study and thallium-201 myocardial perfusion imaging at rest and after bicycle ergometer exercise. Two thirds of the patients had critical AS (valve area index less than or equal to 0.5 cm2/m2) but none had left ventricular systolic dysfunction. Twenty-one patients had angiographically significant CAD (greater than or equal to 50% diameter stenosis in greater than or equal to 1 coronary artery), whereas 23 had either a fully normal angiogram (n = 17) or mild (less than 50%) stenoses (n = 6). Each patient with significant CAD had an abnormal thallium-201 tomogram, either a strictly segmental perfusion defect (n = 19), or a patchy nonsegmental abnormality (n = 2); however, 10 of 23 patients free of significant CAD had similar results. Thus, the sensitivity and specificity of an abnormal scintigram were 100 and 57%, respectively. If only segmental perfusion defects typical of CAD had been considered abnormal, then the sensitivity of the test would have been 90% and the specificity 70%. Patients with false abnormal scintigrams had more severe AS and more angiographically nonsignificant CAD than those with true normal findings.(ABSTRACT TRUNCATED AT 250 WORDS)