Publications by authors named "Arthur Bradwell"

Article Synopsis
  • Acute mountain sickness (AMS) affects many people ascending to high altitudes, but it can be prevented through proper acclimatization and is diagnosed using the Lake Louise Score (LLS).
  • A systematic review was conducted to explore the potential connection between oxygen saturation levels and the likelihood of developing AMS during high altitude ascent.
  • Out of 980 studies reviewed, only seven met the criteria for inclusion, indicating that decreased oxygen saturation measured via pulse oximetry can help predict AMS development, but there's a need for more consistent research methods to improve reliability.
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Acute mountain sickness (AMS) is a well-studied illness defined by clinical features (e.g., headache and nausea), as assessed by the Lake Louise score (LLS).

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Proteinuria is a transient physiological phenomenon that occurs with a range of physical activities and during ascent to altitude. Exercise intensity appears to dictate the magnitude of postexercise proteinuria; however, evidence also indicates the possible contributions from exercise-induced hypoxemia or reoxygenation. Using an environmental hypoxic chamber, this crossover-designed study aimed to evaluate urinary alpha-1 acid glycoprotein (α1-AGP) excretion pre/postexercise performed in hypoxia (HYP) and normoxia (NOR).

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Objective: Altitude-related and exercise-related elevations in blood pressure (BP) increase the likelihood of developing pulmonary hypertension and high-altitude illness during high-altitude sojourn. This study examined the antihypertensive effect and potential exercise benefit of the angiotensin II receptor antagonist losartan when taken at altitude.

Methods: Twenty participants, paired for age and ACE genotype status, completed a double-blinded, randomised study, where participants took either losartan (100 mg/day) or placebo for 21 days prior to arrival at 5035 m (Whymper Hut, Mt Chimborazo, Ecuador).

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Introduction: Proteinuria increases at altitude and with exercise, potentially as a result of hypoxia. Using urinary alpha-1 acid glycoprotein (α1-AGP) levels as a sensitive marker of proteinuria, we examined the impact of relative hypoxia due to high altitude and blood pressure-lowering medication on post-exercise proteinuria.

Methods: Twenty individuals were pair-matched for sex, age and ACE genotype.

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Purpose: Parathyroid cancer is a rare tumor associated with poor prognosis particularly when disseminated. While chemotherapy and/or radiotherapy are of no clinical value in disseminated disease, immunotherapy should be considered.

Subject And Results: A patient with CDC73-associated metastatic parathyroid carcinoma was treated with combined anti-hPTH immunotherapy and surgery.

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Femoroacetabular impingement (FAI) is a common cause of hip pain and represents a major cause of early osteoarthritis. The role of systemic inflammation in pre-arthritic hip conditions remains largely unknown and uninvestigated. Serum-free light chains (sFLCs) are inflammatory markers produced by B cells.

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Background: In multiple myeloma, severe acute kidney injury due to myeloma cast nephropathy is caused by pathogenic free light chain immunoglobulin in serum. High cutoff haemodialysis (HCO-HD) can remove large quantities of free light chain immunoglobulin from serum, but its effect on clinical outcomes is uncertain. We therefore aimed to assess whether HCO-HD could increase the frequency of renal recovery in patients with de novo multiple myeloma, severe acute kidney injury, and myeloma cast nephropathy relative to treatment with standard high-flux haemodialysis (HF-HD).

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Objective: To assess whether acetazolamide (Az), used prophylactically for acute mountain sickness (AMS), alters exercise capacity at high altitude.

Methods: Az (500 mg daily) or placebo was administered to 20 healthy adults (aged 36±20 years, range 21-77), who were paired for age, sex, AMS susceptibility and weight, in a double-blind, randomised manner. Participants ascended over 5 days to 4559 m, then exercised to exhaustion on a bicycle ergometer, while recording breath-by-breath gas measurements.

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Objective: The effect of altitude on brain function is not yet well understood, nor is the influence of height and speed of ascent. Additionally, the relationship between acute mountain sickness (AMS) symptoms and brain function at altitude is unclear. We hypothesized that a deterioration from baseline measures of brain function occurs after rapid, mechanical ascent to 3459 m and would be less pronounced in persons taking acetazolamide.

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Objective: To assess the effect of acetazolamide (Az) on exercise performance during early acclimatization to altitude.

Methods: Az (250 mg twice daily) or placebo was administered for 3 days in a double-blind, randomized manner followed by a rapid ascent to 3459 m in the Italian Alps. Twenty healthy adults (age range, 18-67 years) were tested at 60% of sea-level peak power output for 15 minutes on a bicycle ergometer after 16 to 27 hours of altitude exposure.

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Background: HevyLite™ is a new, recently developed method that facilitates separate quantification of the kappa- and lambda-bounded amounts of a given immunoglobulin (Ig). Using this method, we measured intact immunoglobulin (heavy/light chain; HLC) IgG-kappa, IgG-lambda, IgA-kappa, IgA-lambda individually, as well as their deriving ratios (HLCR) in a series of IgG or IgA multiple myeloma (MM) patients, to investigate and assess the contribution of these tests to disease evaluation.

Patients And Methods: HevyLite™ assays were used in sera from 130 healthy individuals (HI) and 103 MM patients, at time of diagnosis.

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Myeloma kidney is the major cause of severe irreversible renal failure in patients with multiple myeloma. This tubulointerstitial injury is a direct consequence of high concentrations of circulating monoclonal free light chains (FLCs) produced by a clonal expansion of plasma cells. Early reduction of serum FLCs associates with renal recovery, but the target threshold of reduction to facilitate renal recovery is unknown.

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Waldenstrom's macroglobulinemia (WM) is an indolent B-cell lymphoma of the lymphoplasmacytic type accompanied by a serum IgM component. However, conventional IgM quantification lacks sensitivity, does not precisely reflect tumor burden of WM, and, although being the main marker for monitoring response to treatment, may not be accurate. New serum M-component based biomarkers were developed for routine practice in recent years, such as the Freelite® test and more recently the Hevylite test®.

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Free light chain (FLC) removal by high cut-off haemodialysis has been described as an adjuvant therapy for the management of patients with severe renal failure complicating multiple myeloma. The two cases reported here are the first patients in whom this treatment did not remove FLCs. In both patient's sera, size-exclusion chromatography identified large FLC aggregates, with molecular weights above the cut-off of the dialyser.

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Purpose: Chemotherapy in AL (primary or light chain) amyloidosis is associated with improved survival, but its effect on renal outcome has not been examined systematically. The purpose of this study was to evaluate the effect of chemotherapy on clinical outcome among patients with renal AL amyloidosis.

Patients And Methods: We evaluated factors influencing survival among 923 patients with renal AL amyloidosis observed during a 21-year period, including 221 patients who became dialysis dependent.

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Accumulation of amyloid fibrils in the viscera and connective tissues causes systemic amyloidosis, which is responsible for about one in a thousand deaths in developed countries. Localized amyloid can also have serious consequences; for example, cerebral amyloid angiopathy is an important cause of haemorrhagic stroke. The clinical presentations of amyloidosis are extremely diverse and the diagnosis is rarely made before significant organ damage is present.

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Background: Most cases of dialysis-dependent acute kidney injury due to myeloma cast nephropathy do not recover renal function. Renal biopsy typically shows cast formation, direct tubular injury and interstitial inflammation caused by nephrotoxic monoclonal free light chains (FLC). Established scarring at presentation is rarely severe.

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Background: Parathyroid carcinoma (PCa) is a rare disease that can be difficult to differentiate initially from severe benign parathyroid adenoma. PCa oversecrete the amino form of PTH, which is recognized by third-generation but not by second-generation PTH immunoassays. In normal individuals, the third-generation to second-generation PTH ratio should be less than 1.

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