Biomedical subjects

Carolyn Yucha

Publications and source records attributed to Carolyn Yucha.

6 recordsLinked to original sources

PubMed2006

Thermal biofeedback for primary Raynaud's phenomenon: a review of the literature.

The clinical presentation of primary Raynaud's phenomenon (RP) derives from various pathogenic triggers. The use of thermal biofeedback (TBF) may be of benefit in reducing the severity and frequency of attacks. This article summarizes the relevant research regarding the pathophysiology of primary RP and mechanism of TBF for RP. Systematic reviews of the efficacy of TBF for RP and treatment guidelines for clinicians are provided. The panel concludes that the level of evidence for TBF efficacy is categorized as Level IV: efficacious. The rationale, based on three randomized controlled trials conducted in independent laboratories, demonstrated "superiority or equivalence" of treatments that include TBF. However, randomly controlled trials (RCT) with positive clinical outcomes tended to be small. A large RCT with negative results did not effectively teach handwarming skills. Procedures for reviewing and rating of the levels of evidence of efficacy of studies was based on the Template for Developing Guidelines for the Evaluation of the Clinical Efficacy of Psychophysiological Interventions developed by the joint task force of the AAPB and the Society for Neuronal Regulation (SNR).

Biofeedback, Psychology↗

PubMed2003

Renal homeostasis of calcium.

Calcium is critical for many metabolic functions. While 99% of body calcium is found as part of the structure of bone and teeth, 1% found in plasma and body cells is crucial for such functions as blood clotting, nerve impulse conduction, and muscle contraction. The homeostasis of calcium is complex because the gastrointestinal tract, the bones, and the kidneys all affect calcium balance. This manuscript reviews the functions, homeostasis, and renal handling and regulation of calcium. The major sites of renal tubular reabsorption and the related cellular mechanisms are described.

Biological Transport↗

PubMedDate not supplied

Renal handling of phosphorus and magnesium.

The kidney is a major regulator of phosphate and magnesium levels. Phosphate reabsorption occurs primarily in the proximal tubule, driven by sodium reabsorption. Phosphate excretion is regulated by dietary adaptation and is stimulated by parathyroid hormone (PTH). Magnesium reabsorption occurs predominately in the thick ascending limb, driven by the lumen-positive voltage. Its excretion varies with many factors. Increases in extracellular volume, dietary intake, and calcium and the use of thiazide diuretics enhance magnesium excretion.

Calcium↗

PubMedDate not supplied

Renal regulation of acid-base balance.

Because maintaining a normal body pH is essential to the efficient functioning of many physiologic processes, the body has a number of mechanisms that prevent pH fluctuations. Some of these prevent minute-to-minute pH fluctuations over the course of the day, whereas others maintain pH balance from day to day. The kidney plays a key role in both processes. The renal process of bicarbonate reclamation prevents the loss of bicarbonate in the urine and, thus, maintains plasma levels of one substrate that is instrumental to preventing minute-to-minute pH fluctuations. The other renal process, bicarbonate regeneration, replenishes the body's supply of bicarbonate and, thus, maintains pH balance on a day-to-day basis. This article will discuss basic principles of acid-base physiology, the mechanisms that prevent fluctuations in body pH, and the renal processes involved in maintaining a homeostatic pH environment.

Acid-Base Equilibrium↗

PubMedDate not supplied

Urinary concentration and dilution.

Water constitutes approximately 60% of the healthy adult human body. Water balance in the body is regulated by the kidneys, which excrete either concentrated or dilute urine in accordance with physiological needs. This article describes the mechanisms by which the kidneys vary water excretion independent of excretion of other physiological important substrates such as sodium, potassium, hydrogen, and urea. These mechanisms involve the loops of Henle, the distal tubules, the collecting ducts, and the vasa recta, and are under the control of vasopressin (antidiuretic hormone).

Aquaporins↗

PubMedDate not supplied

Renal regulation of extracellular fluid volume and osmolality.

In order for our body cells to function properly, they must be surrounded in extracellular fluid that is relatively constant with regard to osmolality. The kidneys, in concert with neural and endocrine input, regulate the volume and osmolality of the extracellular fluid by altering the amount of sodium and water excreted. This is accomplished primarily through alterations in sodium and water reabsorption, the mechanisms of which differ within each nephron segment.

Absorption↗