Obesity, Abdominal

The goal of this study is to understand the underlying circadian rhythms in subcutaneous adipose tissue of humans with our without continuous feeding and how these are altered in people who have obesity.

A fully functional brown fat helps maintain a healthy weight and decreases the risk of metabolic diseases such as type II diabetes (T2DM). Unfortunately, in human adults, the functionality of brown fat declines with age, and it is one of the reasons for gaining unhealthy weight, particularly around the waistline (central obesity). Currently, scientists do not clearly understand the reasons for the decline in brown fat functionality. It is possible that the decline in the availability of the molecule Nicotinamide Adenine Dinucleotide (NAD+), which is central to several metabolic processes, plays a role in the decline in brown fat metabolism. This project will clarify whether NAD+-based molecular-targeted therapies for the enhancement of whole-body insulin sensitivity and brown fat metabolism will be successful in adult humans, which will eventually be an important target for reducing the development of obesity and its comorbidities such as T2DM.

The goal of this study is to compare two continuous positive airway pressure (CPAP) settings on heart and lung function in patients with severe obesity after anesthesia. The main questions it aims to answer are: 1. Does a recruitment maneuver and CPAP set to intrathoracic pressure (ITP) improve cardiopulmonary function compared to standard CPAP settings in patients with severe obesity after anesthesia? 2. Does the location of adipose tissue influence the response to CPAP settings in patients with severe obesity after anesthesia? Participants will undergo monitoring of their intrathoracic pressure using an esophageal catheter. In the recovery area after anesthesia, participants will receive two CPAP settings, each for 20 minutes. * Intervention 1: Recruitment maneuver and CPAP will set to the level of intrathoracic pressure * Intervention 2: CPAP set to home settings (if OSA is present) or between 8-10 cmH20 (if OSA is not present).

Environmental endocrine disruptors (EDCs) represent a major problem for human health.Some PEEs can accumulate in the fatty tissue of the human body thanks to their lipophilic nature, and are known as persistent organic pollutants (POPs). To assess the benefit of cholestyramine treatment on POPs blood levels in obese patients of childbearing age undergoing bariatric surgery, in order to reduce their preoperative POPs load more rapidly. Indeed, the investigators hypothesize that cholestyramine is capable, outside of acute exposure accidents, of promoting the elimination and release of POPs in the human population. Given this hypothesis, a treatment administered prior to bariatric surgery could reduce pre-operative plasma levels of POPs and thus, in fine, minimize the concentrations reached post-operatively, which are dependent on the release induced by lipolysis (massive and rapid weight loss) and pre-operative plasma concentrations.

The aim of this study is to investigate the relationship between body fat distribution measured by CT scan and related risk factors with the risk of incident metabolic and cardiovascular disease in a prospective cohort study of Japanese men and women. The investigators will also investigate novel risk factors for metabolic and cardiovascular disease using molecular weight-based metallomics analysis.