Search PubMed⌕ Search

Biomedical subjects

K Hall

Publications and source records attributed to K Hall.

At least 307 records · Page 17Linked to original sources

Effect of 24-hour somatostatin infusion on glucose homeostasis and on the levels of somatomedin A and pancreatic and thyroid hormones in man.

In order to investigate whether somatostatin plays a role in the regulation of thyroid hormone secretion we have compared the effects of a prolonged somatostatin infusion on insulin and glucagon levels, on the one hand, with its effect on T4, T3, rT3 and TSH, on the other. Furthermore, the serum levels of somatomedin A were determined. Saline was infused in control experiments. Cyclic somatostatin was given as an i.v. bolus of 200 micrograms followed by a constant rate infusion of 50 micrograms/h during 24 hours. Somatostatin suppressed basal insulin and glucagon levels as well as insulin responses to meals but did not influence somatomedin A levels. T4 and T3 decreased during the first hour, whether somatostatin was given or not. Thereafter, T4 and T3 remained stable in the control experiments, while they continued to decrease slowly when somatostatin was added. The suppressive effect of somatostatin was significant 11 hours (p less than 0.05) and 24 hours (p less than 0.005) after the onset of the infusion. In contrast, rT3 and TSH were not suppressed by somatostatin. The fact that basal TSH did not decrease, favors the idea that the suppression of T4 and T3 was mainly due to a direct inhibitory effect of somatostatin on the thyroid gland. Our observation that a low dose of somatostatin decreases peripheral T4 and T3 levels supports the idea that somatostatin plays a role in the regulation of thyroid hormone secretion.

Adult↗

Immunoreactive somatomedin A in human serum.

A RIA has been developed for somatomedin A (SM-A) utilizing Sepharose-bound antibodies. This assay, measuring SM-A, the insulin-like growth factors 1 and 2, and somatomedin C, allows determination in serum samples. In comparison with a serum standard, the mean serum levels in patients with acromegaly or GH deficiency and healthy subjects were 8.7 %/- 0.7 (n = 25), 0.24 +/- 0.02 (n = 25), and 1.15 +/- 0.11 U/ml, respectively. The correlation coefficient between immunoreactive SM-A and SM-A by radioreceptor assay was highly significant (r = 0.93), although the potency ratio of SM-A between the two groups of patients was higher in the RIA than in the radioreceptor assay. Gel chromatography revealed that SM-A in acromegalic serum is bound to a carrier protein which is absent in patients with GH deficiency. After gel chromatography at low pH, 90% of applied immunoreactive SM-A was recovered in the low molecular weight fraction and consisted mainly of neutral polypeptides.

Acromegaly↗

Serum somatomedin A in chronic renal failure.

The serum levels of somatomedin A, determined by radioreceptor assay, were significantly higher in 57 adult patients with chronic renal failure (X = 2.57 +/- 0.12 U/ml) than in healthy subjects (n = 131; X = 0.77 +/- 0.02 U/ml). A positive correlation was found between somatomedin A and creatinine levels (r = 0.33), but somatomedin A levels did not decrease after hemodialysis. A reduction was only observed after successful renal allografting. Immunoreactive somatomedin A was also found to be increased in patients with chronic renal failure (X = 2.61 +/- 0.21 U/ml), whereas low levels were obtained by the chick bioassay. However, after separating the inhibitory factors from the stimulatory factors by gel chromatography at neutral pH, uremic serum was shown to contain increased levels of somatomedin activity. Although all somatomedin A, determined by different techniques, was present in high molecular forms, the elution pattern differed from that seen in patients with acromegaly.

Adolescent↗

[Multiple intracranial mycotic aneurysms. Case report].

The case of a 31 years old woman with multiple intracranial mycotic aneurysms in association with subacute bacterial endocarditis is reported. The authors discuss the clinical and pathological aspects of such lesions. The complete regression of all the aneurysms after antibiotic therapy favours an approach aiming at adequate control of the infection prior to any consideration of surgical treatment.

Adult↗

The influence of early nutrition on growth and the circulating levels of immunoreactive somatomedin A.

The effect of nutrition during early development on growth and serum immunoreactive somatomedin A was examined in rats by rearing in small or large liters. At weaning, body weight, brain weight, liver weight and DNA content was significantly reduced in rats whose nutrition was restricted by rearing in large litters. Brain DNA content was significantly altered. Serum somatomedin A was significantly reduced in the growth-retarded rats as compared to those whose growth was enhanced by rearing in small litters. Similarly, maternal serum somatomedin A was significantly reduced in rats nursing large litters.

Animals↗

Positive rubella titers in pregnancy: a question of validity.

A review of 25 patients with more than 1 rubella titer by hemagglutination-inhibition testing revealed 3 patients with high positive titers that were reported to be negative in subsequent pregnancies. None of the patients had received the rubella vaccine. Because the sensitivity and reliability of hemagglutination-inhibition testing is markedly influenced by multiple variables, it is important for both the clinician and the pathologist to be aware of both the limitations of the testing method and the meaning of an antibody titer on a single isolated specimen.

Antibodies, Viral↗

CT scan appearances in Leigh's disease (subacute necrotizing encephalomyelopathy).

Four cases of Leigh's disease (subacute necrotizing encephalomyelopathy), two confirmed at postmortem examination, have been investigated recently by CT scanning. All four showed the same symmetrical areas of low attenuation in the basal ganglia, especially the putamina. These areas corresponded with the typical areas of necrosis seen in this disease. There was also some evidence of atrophic change in the posterior fossa in some cases. This CT scan appearance may be diagnostic in the appropriate clinical context.

Brain↗

Metrizamide CT cisternography combined with Myodil (Pantopaque) cisternography in the investigation of suspected small acoustic neuromata.

A combined technique for the investigation of suspected small acoustic neuromata, involving the performance of a metrizamide CT cisternogram, a Myodil (Pantopaque) cisternogram, and also an estimation of the CSF protein level, all at the same examination, is described. An entirely negative result excludes an acoustic neuroma. A few illustrative abnormal cases are described.

Brain↗

Are there schizophrenics for whom drugs may be unnecessary or contraindicated?

This study reports that there are schizophrenics who do relatively well long term without the routine or continuous use of antipsychotic medication. Specially selected young males undergoing an acute schizophrenic episode were followed, after hospitalization, for up to three years. While hospitalized they were assigned randomly to either placebo or chlorpromazine treatment. Many unmedicated-while-in-hospital patients showed greater long-term improvement, less pathology at follow-up, fewer rehospitalizations and better overall function in the community than patients who were given chlorpromazine while in the hospital. Factors related to post-hospital outcome were good premorbid history and short-lived paranoid characteristics. Considerations which may have an effect on the successful management of acute schizophrenic patients not on medication are mentioned. The findings underline the need for further study of how to utilize antipsychotic medication more selectively in the treatment of schizophrenia.

Adolescent↗

Treatment of pituitary dependent Cushing's syndrome with closed stereotactic radiosurgery by means of 60Co gamma radiation.

Four patients with pituitary dependent Cushing's syndrome were treated with external irradiation to the pituitary using 60Co gamma irradiation given with a stereotactic technique. The size of the sella turcica was normal or slightly enlarged in all patients. The doses given varied between 7000 and 10 000 rad, and the observation time ranged between 14 and 20 months. Three of the patients showed complete clinical remission and one marked improvement. One patient developed ACTH insufficiency, while none developed insufficient secretion of other pituitary hormones. No complicants of the irradiation were observed.

Adrenocorticotropic Hormone↗