Effects of Low-Carbohydrate versus Mediterranean Diets on Weight Loss, Glucose Metabolism, Insulin Kinetics and β-Cell Function in Morbidly Obese Individuals.

Low-calorie Mediterranean-style or low-carbohydrate dietary regimens are widely used nutritional strategies against obesity and associated metabolic diseases, including type 2 diabetes. The aim of this study was to compare the effectiveness of a balanced Mediterranean diet with a low-carbohydrate diet on weight loss and glucose homeostasis in morbidly obese individuals at high risk to develop diabetes. Insulin secretion, insulin clearance, and different β-cell function components were estimated by modeling plasma glucose, insulin and C-peptide profiles during 75-g oral glucose tolerance tests (OGTTs) performed at baseline and after 4 weeks of each dietary intervention.

A Pilot Study of Infrared Thermography Based Assessment of Local Skin Temperature Response in Overweight and Lean Women during Oral Glucose Tolerance Test.

Obesity is recognized as a major public health issue, as it is linked to the increased risk of severe pathological conditions. The aim of this pilot study is to evaluate the relations between adiposity (and biophysical characteristics) and temperature profiles under thermoneutral conditions in normal and overweight females, investigating the potential role of heat production/dissipation alteration in obesity. We used Infrared Thermography (IRT) to evaluate the thermogenic response to a metabolic stimulus performed with an oral glucose tolerance test (OGTT).

Multimodal Imaging for the Detection of Brown Adipose Tissue Activation in Women: A Pilot Study Using NIRS and Infrared Thermography.

Purpose: A clear link between obesity and brown adipose tissue (BAT) dysfunction has been recently demonstrated. The purpose of this pilot study is to determine if near-infrared spectroscopy (NIRS) 2D imaging together with infrared thermography (IRT) is capable of identifying thermal and vascular response in the supraclavicular (SCV) areas after the ingestion of an oral glucose load as a thermogenic stimulation.

Method: We studied two groups of women (obese versus lean) for discerning their different responses.

Conventional insulin vs insulin infusion therapy in acute coronary syndrome diabetic patients.

Aim: To evaluate the impact on glucose variability (GLUCV) of an nurse-implemented insulin infusion protocol when compared with a conventional insulin treatment during the day-to-day clinical activity.

Methods: We enrolled 44 type 2 diabetic patients (n = 32 males; n = 12 females) with acute coronary syndrome (ACS) and randomy assigned to standard a subcutaneous insulin treatment (n = 23) or a nurse-implemented continuous intravenous insulin infusion protocol (n = 21). We utilized some parameters of GLUCV representing well-known surrogate markers of prognosis, i.

On the paradox insulin resistance/insulin hypersensitivity and obesity: two tales of the same history.

Insulin resistance (IR) associated with obesity represents a well-known risk factor for chronic disease. IR development may occur to hinder stressful conditions to provide an appropriate energetic supply to non-insulin-sensitive tissues. However, conditions of stress turn out to be 'maladaptive' in the long term, leading to chronic diseases.

Effects of age and physical fitness on microcirculatory function.

Sedentary aging is associated with endothelial dysfunction and nitric oxide (NO) impairment. The aim of the present study was to assess the effects of regular physical exercise on nitrite/nitrate (NOx) concentrations and microcirculatory function in older men compared with young individuals. We measured NOx plasma concentrations and baseline and stimulated skin blood flow (SBF) by laser Doppler flowmetry in 39 male athletes [range, 22-72 years; maximal oxygen consumption (VO2max), 60.

A comparative study of the in vitro antioxidant activity of statins.

Background: Treatment of hypercholesterolemia with statins is remarkably effective in cardiovascular prevention. This has led to the hypothesis that these drugs may act on the atherosclerotic plaque by mechanism(s) independent of the reduction of serum cholesterol levels. The aim of this study was to assess the total antioxidant activity of the most prescribed statins: fluvastatin, atorvastatin, pravastatin and simvastatin.

Metabolic effects of combined antihypertensive treatment in patients with essential hypertension.

Single-drug treatment of essential hypertension (HT) is often insufficient to normalize blood pressure (BP), and high doses of antihypertensive agents can have adverse effects on glucose tolerance (GT) and insulin sensitivity. This study tested whether aggressive BP lowering with combination treatment had any influence on GT or insulin action. In all, 29 nonobese (body mass index [BMI], <30 kg/m ), normolipidemic patients with established HT (159 +/- 3/99 +/- 1 mm Hg) but normal GT were recruited.

Effective blood pressure treatment improves LDL-cholesterol susceptibility to oxidation in patients with essential hypertension.

Objectives: LDL-cholesterol particles from hypertensive patients exhibit enhanced susceptibility to in vitro oxidation, an abnormality thought to increase cardiovascular risk. We tested whether blood pressure (BP) normalization can reverse this abnormality.

Design: Double-blind, randomized pharmacological intervention trial.

Effect of physiological hyperinsulinemia on gluconeogenesis in nondiabetic subjects and in type 2 diabetic patients.

Gluconeogenesis (GNG) is enhanced in type 2 diabetes. In experimental animals, insulin at high doses decreases the incorporation of labeled GNG precursors into plasma glucose. Whether physiological hyperinsulinemia has any effect on total GNG in humans has not been determined.

Metabolic effects of glucose-insulin infusions: myocardium and whole body.

In target organs, insulin switches substrate utilization from free fatty acids to glucose, a change that: (i) is oxygen-efficient; (ii) repletes glycogen stores; (iii) removes potentially toxic fatty acids; and (iv) restores intracellular potassium. During or after an ischaemic challenge, the insulin metabolic mode should protect cellular functions provided that insulin can reach the ischaemic tissue. Insulin, however, also exerts non-metabolic effects, such as membrane hyperpolarization, the stimulation of adrenergic activity, and inhibition of parasympathetic tone, which may counter its beneficial metabolic actions.

Evidence that acute insulin administration enhances LDL cholesterol susceptibility to oxidation in healthy humans.

Increased free radical production and hyperinsulinemia are thought to play a role in experimental and human atherosclerosis, but the relation between the 2 abnormalities has not been studied. In 23 healthy volunteers, we measured the susceptibility of circulating low-density lipoprotein (LDL) cholesterol particles to in vitro copper sulfate oxidation (measured as the lag phase) and cell-mediated oxidative modification (measured as malondialdehyde generation in LDL during incubation with human umbilical vein endothelial cells), as well as the vitamin E content of LDL cholesterol at baseline and after 2 hours of physiological hyperinsulinemia (euglycemic insulin clamp). The lag time of LDL oxidation decreased from control values of 108+/-3 and 107+/-3 minutes (at baseline and after 2 hours of saline infusion) to 101+/-3 minutes after 2 hours of clamping (P<0.

Survival after massive (>2000) Africanized honeybee stings.

We report the clinical case of a man who survived a massive attack of Africanized bees (>2000 bee stings). The man experienced anaphylactic shock and multisystem organ failure (neurologic, hepatic, renal, and hematologic failure). He was treated with administration of dopamine hydrochloride, antihistaminic agents, corticosteroids, fluid and electrolyte replenishment, peritoneal dialysis, and plasmapheresis.

Pyoderma gangrenosum and extensive caval thrombosis associated with the antiphospholipid syndrome--a case report.

Pyoderma gangrenosum is a rare cutaneous disorder frequently associated with systemic diseases. The authors report the case of a 28-year-old man with pyoderma gangrenosum and inferior cava vein syndrome due to thrombosis. The search for pyoderma gangrenosum-associated conditions (gastrointestinal, rheumatic, neoplasic, and infectious diseases) was negative.

Vasodilation with sodium nitroprusside does not improve insulin action in essential hypertension.

The vasodilation induced by systemic insulin infusion is mediated by nitric oxide and is impaired both in obese subjects and patients with essential hypertension. Whether this vascular defect explains the metabolic resistance to insulin action is uncertain. In 8 overweight male patients with essential hypertension, we used the double forearm (ie, infused versus control) technique, combined with the euglycemic hyperinsulinemic clamp, to test whether sustained vasodilation (induced by intra-arterial sodium nitroprusside infusion) improves insulin-mediated glucose uptake.

Metabolic profile and insulin sensitivity in healthy young Mexicans with a strong family history of non-insulin-dependent diabetes mellitus in the paternal branch.

The objective was to identify early metabolic defects and insulin sensitivity in a group of healthy young Mexicans with a family history of NIDDM in first and second degree on the paternal branch. The design was a cross-sectional study, and the setting was a hospital and a school of medicine in Guadalajara, Jalisco, Mexico. The subjects were 20 healthy, non-obese, young (age 19-20 years), born in Mexico, with family history of NIDDM in first and second degree in the paternal branch, and 20 controls.

Insulin sensitivity, vascular reactivity, and clamp-induced vasodilatation in essential hypertension.

Background: Insulin resistance and vascular abnormalities have both been described in patients with essential hypertension. Whether these defects are associated with one another in the same individual has not been established.

Methods And Results: Whole-body insulin sensitivity (by the insulin clamp technique), forearm minimal vascular resistances, and the dose-response curve to acetylcholine, sodium-nitroprusside, and norepinephrine were measured in a group of 29 male patients with untreated essential hypertension.

Renal effects of insulin in man.

We review some of the effects that insulin exerts on glomerular and tubular functions. In healthy subjects, insulin has little or no effect on renal hemodynamics, glomerular filtration rate, or permeability to albumin. In patients with noninsulin-dependent diabetes, hyperinsulinemia selectively increases urinary albumin excretion.

Effect of insulin on systemic and renal handling of albumin in nondiabetic and NIDDM subjects.

Insulin resistance and hyperinsulinemia cluster with microalbuminuria in both diabetic and nondiabetic subjects, but the mechanism underlying this association is unknown. To test the hypothesis that insulin influences protein permeability, we measured the albumin transcapillary escape rate (TER) by the (131)I-labeled albumin technique in 12 healthy volunteers and 12 normoalbuminuric NIDDM patients (fasting plasma glucose, 10.9 +/- 1.

Delta-aminolevulinic acid dehydratase and zinc protoporphyrin in very low lead-exposed pets: a community study.

Markers of lead intoxication have been developed based on their capacity to identify lead intoxication at the preclinical, ie biochemical stage of manifestation. However, little information on these markers is available under conditions of low lead exposure. This prompted us to conduct a community-based study to determine the usefulness of theta-aminolevulinic acid dehydratase (ALAD) and zinc protoporphyrin (ZnPP) in conditions of low lead environmental exposure by studying the relationships between low blood lead levels, ALAD and ZnPP in a large group of healthy dogs living in an Italian urban area.

Renovascular hypertension and insulin sensitivity.

We tested the hypothesis that the status of the renin-angiotensin-aldosterone system affects insulin sensitivity. Insulin sensitivity (by the euglycaemic insulin clamp technique) was measured in eight patients with angiographically proven renovascular hypertension and in eight normotensive subjects matched for age, gender, body mass index and glucose tolerance. In the patients, insulin sensitivity was measured both at baseline and following 7 days of ACE inhibition.

Hyperinsulinemia in glucose-tolerant women with preeclampsia. A controlled study.

Essential hypertension is associated with insulin resistance and hyperinsulinemia. To assess whether hyperinsulinemia is also present in hypertensive disease induced by pregnancy, we studied the plasma glucose and insulin responses to 50 g of oral glucose in 10 women with definite, severe preeclampsia but normal glucose tolerance, and compared them with the responses observed in a well-matched control group of healthy pregnant women. Fasting plasma glucose concentrations were similar in healthy and preeclamptic pregnant mothers (4.

Insulin resistance in microalbuminuric hypertension. Sites and mechanisms.

Microalbuminuria in patients with essential hypertension is a marker of incipient glomerular dysfunction and clusters with lipid and hemodynamic abnormalities. Recent evidence has shown that hypertensive patients with microalbuminuria have a hyperinsulinemic response to oral glucose, suggesting the presence of insulin resistance. To directly test this possibility we studied insulin action in two accurately matched groups (n = 10 each) of hypertensive patients with or without microalbuminuria (14 +/- 2 versus 52 +/- 7 mg/24 h-1, mean of three 24-hour collections).

Effect of insulin on uric acid excretion in humans.

Although hyperuricemia is a frequent finding in insulin-resistant states, insulin's effect on renal uric acid (UA) handling is not known. In 20 healthy volunteers, diastolic blood pressure, body weight, and fasting plasma insulin were positively (and age was negatively) related to fasting plasma UA concentrations, together accounting for 53% of their variability. During an insulin clamp, urine flow was lower than during fasting conditions (1.

Relationship between insulin release, antinatriuresis and hypokalaemia after glucose ingestion in normal and hypertensive man.

1. Insulin simultaneously causes hypokalaemia and antinatriuresis, and it has been suggested that the two effects are tightly coupled. Whether these actions are preserved in patients with essential hypertension is not known.