Biomedical subjects
Publications and source records attributed to G Gwinup.
Oral and maxillofacial surgeons, in the course of patient evaluation, may incidentally discover abnormalities of the sella turcica. A large percentage of patients with sella deformities will be found to have the empty sella syndrome. The clinical and radiographic manifestations of this disorder, and the significance of this diagnosis, are discussed.
Video games are one of the most popular recreational activities among Americans of all ages, especially teenaged boys and young men. Studies of the health hazards of video-game playing have linked seizures, psychologic disturbances, and other health problems with the games. The study reported here measured changes in blood pressure and heart rate that occurred in 23 young men when they played a video game. The mean systolic blood pressure for the entire group was considerably higher during play than before or after and was significantly higher in novice players than in more skilled players. Heart rate was also significantly higher during play. In view of these results, other cardiovascular changes might be expected to occur during video-game playing. Although the changes reported here were minor, even minor cardiovascular alterations could potentially prove serious in persons with cardiovascular disease.
A number of previous studies has suggested that PTH may possess a hyperlipimic property. We determined various lipid fractions in 24 patients with primary hyperparathyroidism before and 1-3 months after surgical cure. The mean values for serum total cholesterol, triglycerides. LDL-Chol, VLDL-Chol and HDL-Chol did not change significantly with definitive correction of hyperparathyroidism. The mean values for all lipid fractions were comparable to those of the age- and and sex-matched normal control group except for HDL-Chol which was significantly lower in the hyperparathyroid group both before and after definitive cure of hyperparathyroidism. Only one patient with combined elevation of serum triglycerides and cholesterol exhibited normalization of the lipid levels after surgery. Two other patients with hypertriglyceridaemia failed to show any reduction in their triglyceride levels after correction of their hyperparathyroidism. Our data suggest that longstanding elevation of PTH to the extent seen in primary hyperparathyroidism and in the absence of predisposing conditions does not increase serum lipids in human.
Patients with both exophthalmos and hyperthyroidism were treated with different modes of therapy for their hyperthyroidism. Propylthiouracil followed by surgery, propylthiouracil followed by radioactive iodine, propylthiouracil alone, and radioactive iodine alone were used. Some of the patients became hypothyroid and were made euthyroid with levothyroxine sodium. Based on the mode of therapy and whether or not hypothyroidism occurred, each patient was assigned to one of seven groups and followed up for 18 months or longer. Careful exophthalmometry was performed at six-week intervals in all patients. Though progression of exophthalmos was noted in all groups, the group that received propylthiouracil demonstrated the greatest progression of exophthalmos. In the group receiving sodium iodide l 131 therapy and in the group treated surgically, the rate of progression of exophthalmos was lessened with the development of hypothyroidism. Since these hypothyroid patients were made euthyroid with supplemental levothyroxine, it appeared that loss of thyroid tissue, rather than the hypothyroidism per se, was responsible for the decrease in progression of the exophthalmos. The continued progression of exophthalmos in the propylthiouracil-treated group may be related to effects of propylthiouracil on the immune system.
Twenty-five insulin-requiring patients whose diabetes was inadequately controlled on a conventional regimen of short- and intermediate-acting insulin given as two or more injections daily were changed to an alternative program in which approximately 40% to 50% of total insulin requirement was given in a single constant morning dose of ultralente insulin and the remainder in three varying doses of regular insulin, one 30 minutes before each meal. On the alternative program, control improved markedly in 23 of the 25 patients, as evidenced by lower fasting serum glucose concentrations and decreased glycosuria. Control was maintained in all 23 over a follow-up period of 2 to 61 months (mean 14 months).
Explore the source record for details and available documents.
Three patients had starvation-related hypoglycemia that was not responsive to the infusion of glucose. The patients resembled fatal cases of hypoglycemia seen very rarely in victims of kwashiorkor. None of the patients had a history of drug ingestion, nor was there any evidence of endocrine insufficiency. Two of the patients had low serum insulin levels. Complete postmortem examinations were done for all three patients and there was no evidence of islet cell abnormalities or of malignant neoplasms. A syndrome of severe hypoglycemia refractory to therapy, that was occasionally seen, in years past, in starved individuals is confirmed. The mechanisms underlying the disorder are obscure, but a failure of glycogenolysis, neoglucogenesis, or overproduction of insulin appear unlikely possibilities. It is postulated that cells normally impermeable to glucose, when serum insulin levels are low, become permeable in some severely starved patients, for reasons unknown.
Explore the source record for details and available documents.
Two patients with Nelson's syndrome and one patient after bilateral adrenalectomy for Cushing's disease, without any evidence of Nelson's syndrome, were studied with respect to the effect of hydrocortisone, naloxone and valproic acid (a GABA transaminase inhibitor) on ACTH secretion. Hydrocortisone suppressed plasma ACTH concentrations to normal in the patient without Nelson's syndrome, but failed to do so in the two patients with Nelson's syndrome. Naloxone and valproic acid caused a decline in plasma ACTH concentrations in the patients with Nelson's syndrome, but produced no change in the patient without Nelson's syndrome. Secretion of ACTH may thus be influenced by both opiate peptide and by gamma aminobutyric acid, as well as by the cortisol concentration, these agents may act at different sites to inhibit ACTH release by the tumour.
We report the first prospective controlled study designed to determine the effect of vitamin D ingestion on serum calcium concentration in patients with tuberculosis. Every patient admitted to the tuberculosis ward over a 6 month period, who was free of any condition which might influence serum calcium concentration, was randomly assigned to one of two groups. The diet of the first group was substituted with ergocalciferol 5000 units daily. The diet of the second group was not supplemented. In addition, the second group was randomly subdivided into two subgroups. The first subgroup received a diet unrestricted in vitamin D. The second subgroup received a diet containing less than 50 units of vitamin D. Serum calcium was determined at weekly intervals. In contradistinction to the results of a previously reported retrospective study, there was no significant difference between the group receiving supplemental vitamin D and the control group at any time during the entire period of study. Furthermore, there was no significant difference between the subgroup of patients receiving normal dietary vitamin D and the subgroup maintained on the diet restricted in vitamin D.
Explore the source record for details and available documents.
Chronic renal failure is associated with a variety of thyroid function abnormalities. Information on thyroid function in patients with chronic renal failure after successful renal transplantation is limited. We studied thyroid function in 13 such patients and found that serum TT3 in the transplant group (136 +/- 30 ng/ml) was significantly (P less than 0.01) higher than the TT3 in the control group (112 +/- 29 ng/ml). All patients were clinically euthyroid and had normal serum TT4, FT4, FT3, TSH, and TBG levels and a normal T3 resin uptake. The pathogenesis of the observed increased TT3 in these patients is not clear.
Explore the source record for details and available documents.
A 45 year old male with a 12 year history of mild hyperthyroidism and a pituitary tumour is presented. He had both clinical and laboratory evidence of hyperthyroidism and his serum TSH was persistently and markedly elevated. A TRH test resulted in no further rise in serum TSH. No evidence of pituitary or peripheral endocrine deficiencies existed and prolactin levels were normal. Craniotomy was performed and a pituitary adenoma was removed. On light microscopy, it was mostly composed of chromophobes. However, occasional granulated cells were observed, and on electron microscopy, most of the cells contained fine granules, which suggested possible thyrotroph origin of the tumour. One week post-operatively the patient's serum TSH returned to normal. Again, TRH produced no response in TSH. The patient became hypothyroid by clinical and laboratory findings and is currently on thyroid replacement therapy. The previously reported TSH secreting tumours associated with hyperthyroidism are reviewed.
Total serum and urinary thyroxine (T4), triiodothyronine (T3), and thyroxine-binding globulin (TBG) as well as serum free T4, thyroid-stimulating hormone (TSH), and T3 resin uptake (T3RU) were measured in seven patients with the nephrotic syndrome. The nephrotic syndrome was defined by proteinuria exceeding 3 g/24 h. All patients were clinically euthyroid. Most values for total serum T4, free T4, T3, T3RU, TBG, and TSH were within normal limits. However, the mean serum T3 and TBG values were significantly lower in patients compared with the control group. The values (mean +/- 2 SD) for urinary T4 were 24.3 +/- 20.3 in the patient group and 1.5 +/- 0.7 microgram/24 h in the control group. Urinary T3 values for patients and the control group were 2100 +/- 856 and 848 +/- 253 ng/24 h respectively. Urinary TBG was 2.1 +/- 1.8 mg/24 h in the patients and undetectable in the control group. There was no correlation between daily urinary T3 and T4 and urinary TBG. There was a weak correlation between daily urinary protein excretion and urinary T4 (r = 0.5).
Forty-nine patients with Graves' disease were randomly divided into two groups. One group received propylthiouracil, 150 mg every eight hours, and the other group received propylthiouracil, 450 mg as a single daily dose. All patients' conditions were evaluated clinically anc chemically at two-week intervals. The response to the divided dosage schedule was prompt and predictable, and by ten weeks all but one patient had achieved remission. The group that received the single daily dose regimen responded less favorably, and at ten weeks ten patients had failed to achieve remission (P less than .001). However, when these patients' regimens were switched to the every-eight-hour schedule, all but one patient became euthyroid in an additional four weeks.
We describe a new exophthalmometer that is less costly than the Hertel type, has greater accuracy and reliability than the Luedde type, and is simple and easy to use.
The effect of chronic changes in serum glucose concentration on refraction was studied by increasing the dose of insulin or chlorpropamide in 10 diabetic patients who initially had relatively high glucose concentrations. In every case when serum glucose concentration was reduced the vision became less myopic or more hyperopic. To assess acute changes. 10 diabetics (including four with aphakic eyes) were given an intravenous injection of glucose. In patients with intact lenses the vision became more myopic or less hyperopic following the administration of glucose, but in the aphakic eyes hyperopia increased. It is concluded from both the acute and chronic studies that higher levels of serum glucose concentration produce myopia and lower levels produce hyperopia. Furthermore, these changes are related to changes in the optical properties of the crystallin lens.