Biomedical subjects

A R Sharpe

Publications and source records attributed to A R Sharpe.

At least 19 recordsLinked to original sources

PubMed1988

Thyrotropin-induced hyperthyroidism: evidence for a common progenitor stem cell.

A 36-year-old woman with hyperthyroidism, elevated blood thyroid-stimulating hormone (TSH) and alpha-subunit levels, amenorrhea, hyperprolactinemia and no evidence of acromegaly, was found to have a pituitary adenoma containing TSH, alpha-subunit and growth hormone by immunohistochemistry. Preoperative testing revealed elevated TSH and alpha-subunit with no response to thyrotropin-releasing hormone (TRH) but a normal response in prolactin to TRH. Culture of the pituitary cells showed release of TSH, alpha-subunit and prolactin. In vitro, TRH failed to cause TSH discharge; however, it increased prolactin concentrations in the culture medium. Triiodothyronine, added to the pituitary cell culture, resulted in no inhibition of TSH and prolactin discharge. By electron microscopy, the adenoma cells showed features of thyrotrophs. However, some adenoma cells contained fibrous bodies characteristic of some growth hormone cell tumors and acidophil stem cell adenomas, suggesting that the adenoma originated in a common progenitor cell.

Adenoma↗

PubMed1986

Efficacy of radioiodine urinalysis.

Little exists in the literature to support the efficacy of urinalysis for demonstrating thyroid uptake of radioiodine. A review was made of a variety of kinetic models. Computer analysis and graphics were used to assess the variables in the two models chosen for this study. The applicability of each model was tested by using data obtained from a group of euthyroid subjects. The results indicate that using an integral urine-sampling method and a three-component model yields minimum detectable thyroid uptakes which fall well below required reporting limits. Furthermore, the results show that integral urine samples obtained in the first few hours post exposure may be used to predict major thyroid uptakes in time for effective thyroid blocking.

Adult↗

PubMed1983

Cervical distribution of iodine 131 following total thyroidectomy for thyroid cancer.

The use of postoperative radioiodine thyroid scanning has questioned whether total thyroidectomy is surgically possible. Similar to earlier studies, we have found functioning iodine 131 (131I)-avid thyroid tissue in our patients following total thyroidectomy for thyroid cancer. Preoperative and postoperative thyroid scans were compared in 24 patients to study the cervical location of postthyroidectomy residual thyroid tissue. Thyroid scanning detected 44 distinct sites of uptake. Thirty-eight of these foci were located either at the extremes of the upper poles of the thyroid gland (24) or along the embryonic thyroid descent tract (14). We conclude that these foci of 131I uptake represent incomplete resection of normal thyroid tissue, and that surgical attention to these areas should result more frequently in extirpation of the entire thyroid gland.

Adolescent↗

PubMed1982

Relative decreased splenic uptake of Tc-99m-sulfur colloid in patients with pancreatic carcinoma.

Relative spleen/liver activity ratio was determined from posterior projection images using a photodensitometric method. Ratios from scans of 22 patients with proven pancreatic carcinoma (12 from rectilinear scans and 10 from scintillation camera images) were determined and compared to studies from patients documented as normal and to randomly selected liver/spleen imaging studies which had been previously interpreted as normal. The mean ratio from the pancreatic carcinoma group was significantly lower than the means of the respective normal groups (p[t] less than .0001 for rectilinear scans and p[t] less than .001 for scintigrams). There was no significant difference between the means of the proven normal and randomly selected normal groups or between the two pancreatic carcinoma groups. Splenic vascular alteration is discussed as a possible reason for decreased splenic distribution of Tc-99m-sulfur colloid in this patient group.

Adolescent↗

PubMed1982

Glomerular filtration rate in children with advanced chronic renal failure: methods of determination and clinical applications.

The rationale, significance and pitfalls of currently available methods for the determination of glomerular filtration rates in children with advanced chronic renal diseases are reviewed. Normal renal clearances in infants and children from birth to adulthood are presented. Methods of serial measurements of renal function, especially by the reciprocals of serum creatinine concentrations, are evaluated. They are applied clinically to monitor the effectiveness of conservative and new modalities of treatment, such as dietary supplementation with essential amino acids plus their keto analogues, and to determine that 1,25-dihydroxyvitamin-D3 treatment of renal osteodystrophy does not accelerate the deterioration of renal function in children with chronic renal insufficiency.

Adolescent↗

PubMed1981