Publications by authors named "Brent G"

End-stage renal disease (ESRD) patients have an increased incidence of hypothyroidism, and those with serum thyroid stimulating hormone (TSH) levels above the reference range have excess mortality, increased cardiovascular disease, impaired health-related quality of life, and altered body composition. We report a patient with ESRD on chronic hemodialysis and Hashimoto's disease, who is on chronic levothyroxine therapy. Despite a high levothyroxine dose of 2.

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Anti-MDA-5 dermatomyositis (DM) is a subtype of idiopathic inflammatory myopathy, commonly presenting as clinically amyopathic dermatomyositis. It is associated with rapidly progressive interstitial lung disease and a poor prognosis. Here, we present two cases of anti-MDA-5 DM and discuss the challenges associated with timely diagnosis, and the importance of early and aggressive treatment.

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Actinic keratoses (AKs) are common pre-malignant lesions. There are numerous management options including active surveillance, multiple topical therapies, cryotherapy, curettage and cautery, and photodynamic therapy, each with their own risks, benefits and efficacy. Best practice currently involves shared decision-making between patient and clinician, particularly in the setting of multiple management options.

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Advanced differentiated thyroid cancer that is resistant to radioactive iodine therapy may become responsive with a unique treatment combination of chloroquine and vorinostat. This treatment was demonstrated in cellular and animal models of thyroid cancer to inhibit endocytosis of the plasma membrane-bound iodine transporter, NIS, and restore iodine uptake. See related article by Read et al.

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Objective: To examine the relationship between thyroid status and incident kidney dysfunction/chronic kidney disease (CKD) progression.

Patients And Methods: We examined incident thyroid status, ascertained by serum thyrotropin (TSH) levels measured from January 1, 2007, through December 31, 2018, among 4,152,830 patients from the Optum Labs Data Warehouse, containing deidentified retrospective administrative claims data from a large national health insurance plan and electronic health record data from a nationwide network of provider groups. Associations of thyroid status, categorized as hypothyroidism, euthyroidism, or hyperthyroidism (TSH levels >5.

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Thyroid hormone (TH) has actions in every tissue of the body and is essential for normal development, as well as having important actions in the adult. The earliest markers of TH action that were identified and monitored clinically, even before TH could be measured in serum, included oxygen consumption, basal metabolic rate, serum cholesterol, and deep tendon reflex time. Cellular, rodent, amphibian, zebrafish, and human models have been used to study TH action.

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Context: Hypothyroidism is a common yet under-recognized condition in patients with chronic kidney disease (CKD), which may lead to end-organ complications if left untreated.

Objective: We developed a prediction tool to identify CKD patients at risk for incident hypothyroidism.

Methods: Among 15 642 patients with stages 4 to 5 CKD without evidence of pre-existing thyroid disease, we developed and validated a risk prediction tool for the development of incident hypothyroidism (defined as thyrotropin [TSH] > 5.

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Context: Thyroid hormone has been shown to have a protective role in neuronal injury, although the mechanisms have not been established. The cellular response to stress that promotes adaptation and survival has been shown to involve epigenetic modifications.

Objective: We hypothesized that the neuroprotective role of thyroid hormone was associated with epigenetic modifications of histone proteins.

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A highly adaptable and robust terahertz (THz) energy meter is designed and implemented to detect energetic THz pulses from high-intensity (>10 W/cm) laser-plasma interactions on the OMEGA EP. THz radiation from the laser driven target is detected by a shielded pyrometer. A second identical pyrometer is used for background subtraction.

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Fusarium is a polyphyletic genus of plant pathogens, members of which can cause opportunistic human infections with varying superficial and systemic presentations, including disseminated infections which typically occur in immunocompromised patients and have a poor prognosis. Treatment is challenging due to intrinsic resistance to many antifungal agents, and antifungal susceptibility testing is therefore essential. Early suspicion, isolation of the organism, and prompt initiation of management are crucial to improving survival.

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Subclinical hyperthyroidism (SCH) is a laboratory diagnosis defined by a serum thyrotropin (TSH) concentration below the reference range (< 0.4 mU/L in most assays), and a free thyroxine (FT4) and 3,5,3'-triiodothyronine levels (FT3) in the reference range. Many patients diagnosed with SCH will be clinically euthyroid while others may present with manifestations characteristic of thyroid hormone excess, such as tachycardia, tremor, intolerance to heat, bone density loss, or weight loss.

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Introduction: Hypothyroidism is highly prevalent in end-stage kidney disease patients, and emerging data show that lower circulating thyroid hormone levels lead to downregulation of vascular calcification inhibitors and coronary artery calcification (CAC) in this population. To date, no studies have examined the association of serum thyrotropin (TSH), the most sensitive and specific single biochemical metric of thyroid function, with CAC risk in hemodialysis patients.

Methods: In secondary analyses of patients from the Anti-Inflammatory and Anti-Oxidative Nutrition in Hypoalbuminemic Dialysis Patients trial, we examined serum TSH levels and CAC risk assessed by cardiac computed tomography scans collected within a 90-day period.

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The utility of serum thyroglobulin (Tg) measurement following partial thyroidectomy or total/near-total thyroidectomy without radioactive iodine (RAI) for differentiated thyroid cancer is unclear. This systematic review examines the diagnostic accuracy of serum Tg measurement for persistent, recurrent, and/or metastatic cancer in these situations. Ovid MEDLINE, Embase, and Cochrane Central were searched in October 2021 for studies on Tg measurement following partial thyroidectomy or total/near-total thyroidectomy without or before RAI.

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The multiterawatt (MTW) laser, built initially as the prototype front end for a petawatt laser system, is a 1053 nm hybrid system with gain from optical parametric chirped-pulse amplification (OPCPA) and Nd:glass. Compressors and target chambers were added, making MTW a complete laser facility (output energy up to 120 J, pulse duration from 20 fs to 2.8 ns) for studying high-energy-density physics and developing short-pulse laser technologies and target diagnostics.

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Thyroid hormone (TH) and thyroid hormone receptor (THR) regulate stem cell proliferation and differentiation during development, as well as during tissue renewal and repair in the adult. THR undergoes posttranslational modification by small ubiquitin-like modifier (SUMO). We generated the THRA (K283Q/K288R) mouse model for in vivo studies and used human primary preadipocytes expressing the THRA sumoylation mutant (K283R/K288R) and isolated preadipocytes from mutant mice for in vitro studies.

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Article Synopsis
  • Researchers studied the effects of a mutation in the thyroid hormone receptor β (THRB) that prevented its sumoylation, specifically at lysine 146 (K146Q), leading to altered hormone levels and gland size in mice.
  • The K146Q mutant mice had normal thyroid hormone levels (T4) but extremely elevated TSH levels and enlarged pituitary and thyroid glands, suggesting impaired hormonal feedback regulation.
  • The mutation also changed how transcription factors interacted with the TSHβ gene promoter, affecting thyroid hormone production and indicating both TSH-dependent and independent pathways were involved.
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Introduction: Thyroid dysfunction is a highly prevalent yet under-recognized complication in hemodialysis patients. In the general population, hypothyroidism has been associated with endothelial dysfunction due to impaired vasodilator synthesis and activity. Little is known about the association of serum thyrotropin (TSH), the most sensitive and specific single biochemical metric of thyroid function, with endothelial function in hemodialysis patients.

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Thyroid hormone is essential for brain development and brain function in the adult. During development, thyroid hormone acts in a spatial and temporal-specific manner to regulate the expression of genes essential for normal neural cell differentiation, migration, and myelination. In the adult brain, thyroid hormone is important for maintaining normal brain function.

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High-energy deep ultraviolet (UV) sources are required for high-density plasma diagnostics. The fifth-harmonic generation of large-aperture neodymium lasers in ammonium dihydrogen phosphate (ADP) can significantly increase UV energies due to the availability of large ADP crystals. Noncritical phase matching in ADP for (ω + 4ω) was achieved by cooling a 65 × 65-mm crystal in a two-chamber cryostat to 200 K.

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Thyroid hormone signaling plays an essential role in muscle development and function, in the maintenance of muscle mass, and in regeneration after injury, via activation of thyroid nuclear receptor alpha (THRA). A mouse model of resistance to thyroid hormone carrying a frame-shift mutation in the THRA gene (THRA-PV) is associated with accelerated skeletal muscle loss with aging and impaired regeneration after injury. The expression of nuclear orphan receptor chicken ovalbumin upstream promoter-factor II (COUP-TFII, or Nr2f2) persists during myogenic differentiation in THRA-PV myoblasts and skeletal muscle of aged THRA-PV mice and it is known to negatively regulate myogenesis.

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