Publications by authors named "Lewis Landsberg"

: To explore relationships between PET/CT characteristics of cold-activated brown adipose tissue (BAT), measures of adiposity and metabolic markers.: We conducted a post-hoc analysis of a study which utilized PET/CT to characterize BAT. 25 men ages 18-24 (BMI 19.

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Purpose: To implement quantitative Dixon magnetic resonance imaging (MRI) methods for brown adipose tissue (BAT) characterization at inactive and cold-activated states in normal weight, overweight, and obese subjects. The hypotheses are that MRI characteristics of BAT would differentiate between nonobese and obese subjects, and activation of BAT in response to thermal challenges that are detected by MRI would be correlated with BAT activity measured by positron emission tomography / computed tomography (PET/CT).

Materials And Methods: Fifteen male subjects (20.

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Objective: Weight gain during the menopausal transition is common. Although studies have suggested that weight gain is more likely related to aging than menopause, there is a reduction in resting energy expenditure with surgical or natural menopause which is independent of age and changes in body composition. The underlying mechanisms could include a reduction in core body temperature.

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In light of the worldwide epidemic of obesity, and in recognition of hypertension as a major factor in the cardiovascular morbidity and mortality associated with obesity, The Obesity Society and The American Society of Hypertension agreed to jointly sponsor a position paper on obesity-related hypertension to be published jointly in the journals of each society. The purpose is to inform the members of both societies, as well as practicing clinicians, with a timely review of the association between obesity and high blood pressure, the risk that this association entails, and the options for rational, evidenced-based treatment. The position paper is divided into six sections plus a summary as follows: pathophysiology, epidemiology and cardiovascular risk, the metabolic syndrome, lifestyle management in prevention and treatment, pharmacologic treatment of hypertension in the obese, and the medical and surgical treatment of obesity in obese hypertensive patients.

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In light of the worldwide epidemic of obesity, and in recognition of hypertension as a major factor in the cardiovascular morbidity and mortality associated with obesity, The Obesity Society and the American Society of Hypertension agreed to jointly sponsor a position paper on obesity-related hypertension to be published jointly in the journals of each society. The purpose is to inform the members of both societies, as well as practicing clinicians, with a timely review of the association between obesity and high blood pressure, the risk that this association entails, and the options for rational, evidenced-based treatment. The position paper is divided into six sections plus a summary as follows: pathophysiology, epidemiology and cardiovascular risk, the metabolic syndrome, lifestyle management in prevention and treatment, pharmacologic treatment of hypertension in the obese, and the medical and surgical treatment of obesity in obese hypertensive patients.

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Maintenance of core temperature is a major component of 24-h energy expenditure, and its dysregulation could contribute to the pathophysiology of obesity. The relationship among temperature, sex, and BMI, however, has not been fully elucidated in humans. This study investigated core temperature in obese and lean individuals at rest, during 20-min exercise, during sleep, and after food consumption.

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Understanding the pathogenesis of obesity is now more important than ever, given the remarkable world-wide epidemic. This paper explores the potential role of core temperature in energy balance, and develops the hypothesis that basal temperature and changes in the temperature response in various situations contribute to the enhanced metabolic efficiency of the obese state. The argument is based on the important contribution that heat production makes in establishing the basal or resting metabolic rate, as well as on an analysis of the adaptive role played by changes in temperature in response to environmental challenge.

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The global increase in obesity, along with the associated adverse health consequences, has heightened interest in the fundamental causes of excessive weight gain. Attributing obesity to "gluttony and sloth", blaming the obese for overeating and limiting physical activity, oversimplifies a complex problem, since substantial differences in metabolic efficiency between lean and obese have been decisively demonstrated. The underlying physiological basis for these differences have remained poorly understood.

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1. The current worldwide epidemic of obesity and its major complications, namely type 2 diabetes and hypertension, is well documented. The present mini-review develops the thesis that 'thrifty' metabolic traits, evolved in the setting of intermittent famine, contribute to the obesity pandemic.

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: 1. The use of tritiated norepinephrine (NE) to measure the turnover rate of NE in sympathetically innervated organs was pioneered in the laboratory of Julius Axelrod. This technique provides an organ specific assessment of sympathetic activity, integrated over a 24 h period, in free living laboratory animals.

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Hypertension occurs in approximately 30% of patients with type 1 diabetes and from 50 to 80% of patients with type 2 diabetes. Although the pathogenesis of hypertension is distinct in each type, hypertension markedly enhances the already high risk of cardiovascular and renal disease in types 1 and 2 and implications for treatment are similar in both. The threshold for blood pressure treatment in diabetic patients is generally agreed to be 140/90 mm/hg with a target BP of < 130/80.

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The role of sympathetic innervation in regulation of thyroid function is incompletely understood. We, therefore, carried out studies in rats utilizing techniques of norepinephrine turnover to assess thyroid sympathetic activity in vivo. Thyroidal sympathetic activity was increased 95% by exposure to cold (4 degrees C), 42% by chronic ingestion of an iodine-deficient diet, and 32% in rats fed a goitrogenic diet (low-iodine diet supplemented with propylthiouracil).

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We examined relationships between repression, general maladjustment, body mass index (BMI), and waist-to-hip ratio (WHR). The participants were 1,081 healthy older men from the Normative Aging Study. Repression and General Maladjustment Scales of the Minnesota Multiphasic Personality Inventory were composite measures of personality.

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