Publications by authors named "Chuanyun Gao"

Telemedicine use became widespread at our weight management center in 2020 due to the coronavirus disease 2019 (COVID-19) pandemic. The objective of this study was to determine patient and provider satisfaction with telemedicine visits at a community-based hospital in the United States. Patients and providers were electronically surveyed at the end of 2020 regarding telemedicine visit experiences.

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Diabetic kidney disease causes significant morbidity and mortality among people with type 1 diabetes (T1D). Intensive glucose and blood pressure control have thus far failed to adequately curb this problem and therefore a major need for novel treatment approaches exists. Multiple observations link serum uric acid levels to kidney disease development and progression in diabetes and strongly argue that uric acid lowering should be tested as one such novel intervention.

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Leptin is an adipocyte-derived hormone that controls food intake and reproductive and immune functions in rodents. In uncontrolled human studies, low leptin levels are associated with impaired immune responses and reduced T-cell counts; however, the effects of leptin replacement on the adaptive immune system have not yet been reported in the context of randomized, controlled studies and/or in conditions of chronic acquired leptin deficiency. To address these questions, we performed a randomized, double-blinded, placebo-controlled trial of recombinant methionyl-human leptin (metreleptin) administration in replacement doses in women experiencing the female triad (hypothalamic amenorrhea) with acquired chronic hypoleptinemia induced by negative energy balance.

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Objective: To investigate the effect of treatment with the glucagon-like peptide 1 receptor agonist exenatide on weight loss and metabolic parameters in obese nondiabetic women.

Research Design And Methods: Forty-one obese women (aged 48 ± 11 years and BMI 33.1 ± 4.

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Strenuously exercising young women with hypothalamic amenorrhea are hypoleptinemic and have low bone mineral density (BMD) and content (BMC), which predispose them to increased fracture risk. Short-term leptin replacement in these women corrects many neuroendocrine abnormalities and increases circulating levels of bone formation markers. Whether treatment with recombinant methionyl human leptin (metreleptin) for a long period improves BMD and BMC remains unknown.

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Hypothalamic amenorrhea (HA) is associated with dysfunction of the hypothalamic-pituitary-peripheral endocrine axes, leading to infertility and bone loss, and usually is caused by chronic energy deficiency secondary to strenuous exercise and/or decreased food intake. Energy deficiency also leads to hypoleptinemia, which has been proposed, on the basis of observational studies as well as an open-label study, to mediate the neuroendocrine abnormalities associated with this condition. To prove definitively a causal role of leptin in the pathogenesis of HA, we performed a randomized, double-blinded, placebo-controlled trial of human recombinant leptin (metreleptin) in replacement doses over 36 wk in women with HA.

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Actions of adenosine 5'-monophosphate (AMP) on electrical and synaptic behavior of submucosal neurons in guinea pig small intestine were studied with "sharp" intracellular microelectrodes. Application of AMP (0.3-100 microM) evoked slowly activating depolarizing responses associated with increased excitability in 80.

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Electrophysiologic recording methods were used to study the actions of galanin on synaptic transmission in the submucous plexus of guinea pig ileum. Exposure to galanin resulted in concentration-dependent suppression of slow noradrenergic inhibitory postsynaptic potentials and fast nicotinic excitatory postsynaptic potentials in the majority of neurons. Failure of galanin to suppress nicotinic depolarizing responses to micropressure pulses of acetylcholine and failure to suppress hyperpolarizing responses to micropressure pulses of norepinephrine suggested that galanin acted at presynaptic inhibitory receptors to suppress release of acetylcholine and norepinephrine.

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Conventional intracellular microelectrodes, neuronal tracer injection techniques and immunohistochemistry were used to study the actions of cysteinyl leukotrienes (CysLTs) on electrical and synaptic behavior of enteric neurons in guinea-pig stomach and small intestine. Bath application of leukotriene C(4), leukotriene D(4) or leukotriene E(4) evoked a slowly activating depolarizing response in most of the myenteric and submucous plexus neurons in the small intestine while no effect was observed in gastric neurons. The depolarization evoked by cysteinyl leukotrienes in intestinal neurons was associated with increased input resistance and enhanced excitability.

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Background & Aims: Serine proteases are postulated to influence gastrointestinal function by stimulating protease-activated receptors (PARs). This study identified the effects on myenteric neurons of activating PARs and investigated underlying mechanisms of action.

Methods: Intracellular electrophysiologic methods were used to study the effects of proteases on electrical and synaptic behavior of morphologically identified neurons in the guinea pig enteric nervous system.

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Enteric neuroimmune interactions in gastrointestinal hypersensitivity responses involve antigen detection by mast cells, mast cell degranulation, release of chemical mediators, and modulatory actions of the mediators on the enteric nervous system (ENS). Electrophysiological methods were used to investigate electrical and synaptic behavior of neurons in the stomach and small intestine during exposure to beta-lactoglobulin in guinea pigs sensitized to cow's milk. Application of beta-lactoglobulin to sensitized preparations depolarized the membrane potential and increased neuronal excitability in small intestinal neurons but not in gastric neurons.

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Electrophysiologic recording and indirect immunofluorescence were combined to study localization of the medium-sized neurofilament 145 (NF145) component of the cytoskeleton in morphologically identified neurons in the myenteric and submucosal plexuses of the guinea pig enteric nervous system. Neuronal localization of chemical markers, including calbindin DK28, calretinin, nitric oxide synthase, choline-acetyltransferase, neuropeptide Y, serotonin, neurokinin 1 receptor protein, and somatostatin, was integrated with electrophysiologic and morphologic results for a more complete assessment. NF145 immunoreactivity (-IR) was present in ganglion cells with Dogiel type I morphology in the myenteric plexus of the stomach and small and large intestine.

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