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OBJECTIVE Glucagon-like peptide-1 is a nutrient-sensitive hormone secreted from enteroendocrine L cells within the small and large bowel. Although GLP-1 levels rise rapidly in response to food ingestion, the greatest density of L cells is localized to the distal small bowel and colon. Here we assessed the importance of the distal gut in the acute L cell response to diverse secretagogues. METHODS Circulating levels of glucose and plasma GLP-1 were measured in response to administration of L cell secretagogues in wild-type mice and in mice with a) genetic reduction of Gcg expression throughout the small and large bowel (GcgGut-/-) and b) selective reduction of Gcg expression in the distal gut (GcgDistalGut-/-). RESULTS The acute GLP-1 response to olive oil or arginine administration was markedly diminished in GcgGut-/- but preserved in GcgDistalGut-/- mice. In contrast, the increase in plasma GLP-1 levels following administration of the GPR119 agonist AR231453, or the melanocortin-4 receptor (MC4R) agonist LY21e cells as rapid responders to structurally and functionally diverse GLP-1 secretagogues. OBJECTIVE Sirt6 is an essential regulator of energy metabolism in multiple peripheral tissues. However, the direct role of Sirt6 in the hypothalamus, and specifically pro-opiomelanocortin (POMC) neurons, controlling energy balance has not been established. Here, we aimed to determine the role of Sirt6 in hypothalamic POMC neurons in the regulation of energy balance and the underlying mechanisms. METHODS For overexpression studies, the hypothalamic arcuate nucleus (ARC) of diet-induced obese mice were targeted bilaterally and adenovirus was delivered by using stereotaxic apparatus. For knockout studies, the POMC neuron-specific Sirt6 knockout mice (PKO mice) were generated. Acetosyringone cost Mice were fed with chow diet or high-fat diet, and body weight and food intake were monitored. Whole-body energy expenditure was determined by metabolic cages. Parameters of body composition and glucose/lipid metabolism were evaluated. RESULTS Sirt6 overexpression in the ARC ameliorated diet-induced obesity. Conversely, selective Sirt6 ablation in POMC neurons predisposed mice to obesity and metabolic disturbances. PKO mice showed an increased fat mass and food intake, while the energy expenditure was decreased. Mechanistically, Sirt6 could modulate leptin signaling in hypothalamic POMC neurons, with Sirt6 deficiency impairing leptin-induced phosphorylation of signal transducer and activator of transcription 3. The effects of leptin on reducing food intake and body weight, and leptin-stimulated lipolysis were also impaired. Moreover, Sirt6 inhibition diminished the leptin-induced depolarization of POMC neurons. CONCLUSIONS Our results reveal a key role of Sirt6 in POMC neurons against energy imbalance, suggesting Sirt6 is an important molecular regulator for POMC neurons to promote negative energy balance. Neuroimaging and especially MRI has emerged as a necessary imaging modality to detect, measure, characterize and monitor brain tumours. Advanced MRI sequences such as perfusion MRI, diffusion MRI and spectroscopy as well as new post-processing techniques such as automatic segmentation of tumours and radiomics play a crucial role in characterization and follow up of brain tumours. The purpose of this review is to provide an overview on anatomical and functional MRI use for brain tumours boundaries determination and tumour characterization in the specific context of radiotherapy. The usefulness of anatomical and functional MRI on particular challenges posed by radiotherapy such as pseudo progression and pseudo esponse and new treatment strategies such as dose painting is also described. Among the available imaging techniques, functional imaging provided by nuclear medicine departments represents a tool of choice for the oncoradiotherapist for targeting tumour activity, with positron emission tomography as the main modality. Before, during or after radiotherapy, functional imaging helps guide the oncoradiotherapist in making decisions and in the strategic choice of pathology management. Setting up a working group to ensure perfect coordination at all levels is the first step. Key points for a common and coordinated management between the two departments are the definition of an organizational logistic, training of personnel at every levels, standardization of nomenclatures, the choice of adapted and common equipment, implementation of regulatory controls, and research/clinical routine continuum. The availability of functional examinations dedicated to radiotherapy in clinical routine is possible and requires a convergence of teams and a pooling of tools and techniques. BACKGROUND In Canada, hepatitis C virus (HCV) transmission primarily occurs among people who inject drugs (PWID) and people with experience in the prison system bare a disproportionate disease burden. These overlapping groups of individuals have been identified as priority populations for HCV micro-elimination in Canada, which is currently not on track to achieve its elimination targets. Considering the missed opportunities to intervene in provincial prisons, this study aims to estimate the population-level impact of prison-based interventions and post-release risk reduction strategies on HCV transmission among PWID in Montréal, a Canadian city with high HCV burden. METHODS A dynamic HCV transmission model among PWID was developed and calibrated to community and prison bio-behavioural surveys in Montréal. Then, the relative impact of prison-based testing and treatment or post-release linkage to care (both 90% testing and 75% treatment coverage), alone or in combination with strategies that reduce the heighten Prison-based interventions with potential integration of post-release risk reduction measures should be considered as an integral part of HCV micro-elimination strategies in this setting. BACKGROUND Acute lymphoblastic leukemia (ALL) is the most common malignancy in children characterized by the overproduction and accumulation of immature lymphoid cells in the bone marrow and peripheral blood. The BMI-1 is an important component of the Polycomb Repressive Complex-1 (PRC1). It is an important molecule for the self-renewal of hematopoietic stem cells (HSCs). The BMI-1 expression is generally high in HSCs and decreases after cell differentiation. The BMI-1 is required for the maintenance of normal and cancer stem cells and has been reported as an oncogene in various tumors. The NANOG is a homeodomain transcription factor responsible for maintaining the stem cell compartment at the blastocyst stage of developing embryos. The NANOG gene has been proven to be transcribed in CD34+ cells and different leukemic cells. METHODS The ribonucleic acid (RNA) was extracted from the peripheral blood mononuclear cells (PBMNCs) of 30 pediatric ALL patients (16 B-ALL and 14 T-ALL) and 14 healthy controls. The Bmi-1 and NANOG expression levels were determined using the quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR).