Publications by authors named "Michael McPhaul"

Purpose: This study aims to assess the prevalence of intersex variations/differences in sex development (I/DSDs), associated adrenal conditions, and primary gonadal insufficiency in children with gender dysphoria.

Methods: We performed a comprehensive review of the medical records for individuals who carried the diagnostic codes for gender dysphoria in addition to intersex and/or other conditions associated with sex steroid variations among patients evaluated by pediatric endocrinologists from 2013 to 2022.

Results: We found that 9 of 612 (1.

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Article Synopsis
  • High-dose testosterone replacement therapy (TRT) combined with finasteride offers benefits such as improved body composition, muscle strength, and bone density in older men, while mitigating the risk of prostate enlargement.
  • A pilot study involved 12 men with spinal cord injuries, demonstrating that TRT with finasteride significantly increased lean body mass and muscle size, alongside enhancing bone mineral density compared to a placebo.
  • Results suggest TRT + finasteride reduced fat mass and improved muscular strength, with measurable benefits observed as early as 6 months into the treatment, indicating its potential effectiveness for men with low testosterone post-injury.
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Objectives: Limited data are available on the hormonal response of children to venepuncture or intravenous cannulation (IVC). Catecholamines [epinephrine (E) and norepinephrine (NE)] have been traditionally recognized as stress hormones. Copeptin, the carboxyl-terminus of the arginine vasopressin (AVP) precursor peptide, is also a known marker for stressful stimuli, including myocardial infarction, critical illness, and sepsis.

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Background: Fasting intact insulin concentrations can predict metabolic dysfunction-associated steatotic liver disease (MASLD) in adults without diabetes; however, research in youth is limited. We sought to determine whether fasting intact insulin, measured by liquid chromatography-tandem mass spectrometry, is associated with MASLD in children.

Methods: This retrospective cross-sectional analysis used data and samples from children who participated in studies across 3 universities between 2014 and 2022.

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Background: Dysglycemia and insulin resistance increase type 2 diabetes (T2D) and cardiovascular disease (CVD) risk, yet associations with specific glucose-insulin homeostatic biomarkers have been inconsistent. Vitamin D and marine omega-3 fatty acids (n-3 FA) may improve insulin resistance. We sought to examine the association between baseline levels of insulin, C-peptide, HbA1c, and a novel insulin resistance score (IRS) with incident cardiometabolic diseases, and whether randomized vitamin D or n-3 FA modify these associations.

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Background: In many practices, the screening for primary aldosteronism relies on a single-blood draw for plasma aldosterone concentration (PAC) and plasma renin activity (PRA) to establish an aldosterone-to-renin ratio (ARR). ARR levels vary between expert centers and repeated assays in the same individual, emphasizing the potential variability of this screening approach. A suppressed PRA to <1 ng/mL per h has been proposed as an alternative test to the ARR.

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Article Synopsis
  • Statin drugs, which help lower cholesterol and prevent cardiovascular disease, may cause adverse effects in women, especially new-onset diabetes and muscle weakness.
  • Research in female mice shows that these negative effects are linked to lower levels of the omega-3 fatty acid DHA, as well as issues with cellular function and energy production.
  • Administering fish oil to provide DHA can mitigate these adverse effects, and the study suggests that genetic factors related to the X chromosome may increase women's risk, highlighting the potential of DHA supplementation as a helpful therapy.
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Background And Aims: Previous studies have derived and validated an HDL apolipoproteomic score (pCAD) that predicts coronary artery disease (CAD) risk. However, the associations between pCAD and markers of cardiometabolic health in healthy adults are not known, nor are the effects of regular exercise on pCAD.

Methods: A total of 641 physically inactive adults free of cardiovascular disease from the HERITAGE Family Study completed 20 weeks of exercise training.

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Introduction: Stimulated copeptin may provide an alternative to water deprivation testing (WDT) in the evaluation of polyuria-polydipsia syndrome (PPS). Though best studied, arginine stimulation alone produces a modest copeptin response in children. We investigated the effectiveness of the arginine + LevoDopa/Carbidopa stimulation test (ALD-ST) for copeptin.

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Oral calorie intake causes an acute and transient decline in serum testosterone concentrations. It is not known whether this decline occurs in men on testosterone therapy. In this study, we evaluated the change in testosterone concentrations following oral glucose ingestion in hypogonadal men before and after treatment with testosterone therapy.

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Background: Professional guidelines recommend an HbA1c < 7% for most people with diabetes and < 8.5% for those with relaxed glycemic goals. However, many people with type 2 diabetes mellitus (T2DM) are unable to achieve the desired HbA1c goal.

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Objectives: Although AVP and its surrogate, copeptin, are mainly regulated by osmotic and volume stimuli, their secretion is also elicited by stress and growth hormone (GH) stimulating agents. The aim of this report is to describe unusual patterns of copeptin response in a subset of children undergoing GH stimulation tests (GH-ST).

Methods: We conducted a secondary analysis of a cohort of 93 healthy short children with no polydipsia, polyuria or fluid/electrolyte abnormalities, undergoing GH-ST with intravenous arginine, insulin, oral clonidine, or L-Dopa/carbidopa in various combinations.

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High-density lipoproteins (HDLs) are promising targets for predicting and treating atherosclerotic cardiovascular disease (ASCVD), as they mediate removal of excess cholesterol from lipid-laden macrophages that accumulate in the vasculature. This functional property of HDLs, termed cholesterol efflux capacity (CEC), is inversely associated with ASCVD. HDLs are compositionally diverse, associating with >250 different proteins, but their relative contribution to CEC remains poorly understood.

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Objectives: To determine the detection rate of IGF-1 variants in a clinical population and assess their implications.

Methods: IGF-1 variants were detected based on their predicted mass-to-charge ratios. Most variants were distinguished by their isotopic distribution and relative retention times.

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We found that individuals in the top tertile of HOMA-IR and with HbA1c-defined prediabetes have elevated risk of cardiometabolic outcomes.

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Background: Insulin resistance (IR) is associated with cardiovascular disease (CVD). However, insulin immunoassay variability and scarce research of the elderly have hindered the adoption of IR assessment for CVD prevention. We asked whether the probability of having IR [p(IR)]-derived from insulin and C-peptide mass-spectrometry assays-was associated with CVD in the elderly.

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Objective: Insulin resistance (IR) increases risk of type 2 diabetes and atherosclerotic cardiovascular disease and is associated with lipid and lipoprotein abnormalities including high triglycerides (TG) and low high-density lipoprotein cholesterol (HDL-C). Lipoprotein size and lipoprotein subfractions (LS) have also been used to assist in identifying persons with IR. Associations of LS and IR have not been validated using both direct measures of IR and direct measures of LS.

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Introduction: Copeptin, co-secreted with arginine vasopressin, is regulated by osmotic and volume stimuli but also responds to intravenous arginine and insulin-induced hypoglycemia. The serum copeptin response to the latter agents has been studied in adults but only to a limited extent in children. The objective of this study was to describe the copeptin response to combined arginine and insulin in children with normal posterior pituitary function.

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Context: The mechanisms leading to increased cardiovascular disease in patients with nonalcoholic fatty liver disease (NAFLD) and advanced liver fibrosis remain incompletely understood.

Objective: This study assessed HDL-bound proteins in patients with NAFLD with or without advanced fibrosis.

Methods: This cross-sectional study at a university hospital included 185 patients with or without type 2 diabetes (T2D).

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A method for free thyroxine measurement in human serum using equilibrium dialysis followed by liquid chromatography tandem mass spectrometry (LC-MS/MS) is described. Free thyroxine in serum is first separated from protein-bound thyroxine by equilibrium dialysis and then measured by LC-MS/MS.

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Objective: We asked whether the estimated 8-year risk of diabetes could be reduced within the first 2 years of a digital Diabetes Prevention Program (dDPP) in a workforce population.

Methods: Employees and spouses were eligible if they had prediabetes-range fasting glucose or hemoglobin A 1c and body mass index ≥25 kg/m 2 . Diabetes risk was assessed using the Framingham diabetes risk score in the year before and the 2 years after dDPP initiation.

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Objective: Obesity in adolescent males is associated with the lowering of total and free testosterone concentrations. Weight loss may increase testosterone concentrations.

Design And Methods: We evaluated the changes in sex hormones following bariatric surgery in 34 males (age range: 14.

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In clinical trials, vitamin D supplementation has been reported to reduce serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG) but not high-density lipoprotein cholesterol (HDL-C). In this cohort study we evaluated the association between changes in vitamin D (25-hydroxyvitamin D) and changes in lipid levels in a real-world setting. Changes in lipid levels over a 1-year period were evaluated among individuals whose vitamin D levels increased (group 1) or decreased (group 2) by ≥ 10 ng/mL in year 2018 versus 2017 (cohort 1; n = 5580), in 2019 versus 2018 (cohort 2, n = 6057), or in 2020 versus 2019 (cohort 3, n = 7249).

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