Search PubMed⌕ Search

Biomedical subjects

S Hunt

Publications and source records attributed to S Hunt.

At least 127 records · Page 7Linked to original sources

Specific spatial defect in a child with septo-optic dysplasia.

A blind girl with septo-optic dysplasia was compared with a blind, age-matched control on three spatial tests. Previous observations had suggested a specific spatial learning disorder. Results of the tests showed good verbal intelligence but severe impairment of topographical orientation, route-learning and kinaesthetic memory. It is argued that these dysfunctions were a direct consequence of the malformation syndrome, and could not be accounted for by factors such as sex or congenital blindness.

Adolescent↗

Effects of gossypol on sperm counts in two inbred strains of mice.

Gossypol acetic acid was administered orally to mice of two inbred strains, BALB/c/O1a and CBA/Gr, at daily doses of 10 or 20 mg/kg for about 4 weeks. Treated mice of both strains showed a reduction in sperm counts. This was more marked in CBA mice, which also had smaller testes size than did BALB/c mice. The treatment had no significant effect on testicular weight but the caput epididymidis and seminal vesicles of treated mice weighed less than those of control mice.

Animals↗

The glycosaminoglycans of pig colonic wall connective tissue.

Colon wall from pig, stripped of most of the mucosal layer to leave material largely composed of muscle, basement membrane, and extracellular matrix, was subjected to procedures for isolation of glycosaminoglycans. A total ethanol precipitate from a papain digest was fractionated by selective ethanol precipitation in the presence of Ca2+. Glycosaminoglycan fractions, freed proteolytically from a high molecular weight glycoprotein component, were further purified by Sepharose CL-6B gel-filtration or DE-52 anion-exchange chromatography. Glycosaminoglycans were identified by chemical composition, 13C-NMR spectroscopy and response to chondroitinase and nitrous acid degradations. The content of glycosaminoglycan in the tissue is low (0.05% dry weight) being comprised of dermatan sulphate (38%), heparin (34%), heparan sulphate (18%) and chondroitin sulphates (10%) as a percentage of total glycosaminoglycan content. Hyaluronic acid and keratan sulphate have not been detected. The composition is generally typical of a high muscle content tissue.

Animals↗

Combined heart and lung transplantation.

Combined heart and lung transplantation was carried out in ten patients at Stanford University Medical Center between March, 1981, and December, 1982. All patients had end-stage pulmonary hypertension. 7 of them had Eisenmenger's syndrome and 3 primary pulmonary hypertension. 3 patients died within a month of operation, but the remaining recipients are well 2 months to 2 years after transplantation. The hospital stay of the survivors ranged from 38 to 85 days. All survivors have returned to normal activity. The results of heart and lung transplantation have thus been considerably superior to those reported previously for lung transplantation. It is suggested that cardiopulmonary replacement is suitable treatment for end-stage pulmonary hypertension with or without associated congenital heart disease and that its application to other forms of advanced pulmonary failure may be warranted.

Adult↗

Two new sulphur-containing amino acids in man.

Two unusual sulphur-containing amino acids have been isolated from urine of a baby who died with major physical malformations and failure of growth and development. Sensitive mass spectrometric methods were used to identify the nanomole quantities of the compounds available as S-(2-carboxypropyl)-cysteine and S-(2-carboxypropyl)-cysteamine. Incubation of fibroblasts in either [14C]Valine or [35S]cysteine resulted in radioactive labelling of the compounds, suggesting their origin from conjugation of methacrylic acid with cysteine and subsequent decarboxylation of the cysteine conjugate. Specific assay of methacrylyl-CoA hydratase is needed for final proof that this is a new inborn error of that enzyme, but these findings and parental consanguinity make this very likely. It seems possible that methacrylic acid or one of its derivatives may have caused the malformations present in the baby.

Abnormalities, Multiple↗

Photocoagulation for optic disc new vessels in diabetes mellitus.

The effects of treatment by argon laser and xenon arc photocoagulation in 165 diabetic patients with optic disc new vessel formation have been studied retrospectively. Visual acuity and degree of new vessel formation have been assessed over a period of between six months and seven years of follow-up (mean 23 months). Visual acuity improved in 36% of treated eyes and remained unchanged in 34%. Improvement was most marked in those with initially poor acuity (less than 6/36). There was no association between improvement in visual acuity and regression of disc vessels, the latter occurring in 79% of treated eyes. Only 6% of eyes became blind during the period of follow-up, principally as a result of vitreous haemorrhage and retinal detachment. There was no difference between the results produced by the use of separate or combined argon laser and xenon arc photocoagulation on the regression of disc new vessels. However, our results suggest that argon laser treatment was more effective than xenon arc photocoagulation in improving visual acuity. These findings suggest that either form of treatment or a combination offers considerable benefit in the management of proliferative diabetic retinopathy, even when very severe at presentation.

Adult↗

Molluscan visceral muscle fine structure. General structure and sarcolemmal organization in the smooth muscle of the intestinal wall of Buccinum undatum L.

Fine structure of intestinal muscle in the gastropod Buccinum undatum is described. Myofibrillar organization is typical of non-pseudostriated molluscan muscles. The dense body system is poorly developed but there are extensive attachments plaques. The sarcolemma is elaborately modified. Deep infoldings of the membrane give the cells an irregular outline. Such infoldings enclose extracellular matrix and are associated with attachment plaques. Arising from these and from the general sarcolemma are numerous tubular membranous invaginations ending blindly at varying depth in the sarcoplasm. These structures have a helical coat of particles on the cytoplasmic face. Associated with both types of invagination are subsarcolemmal vesicles. The possibility that the tubular invaginations are analogues of vertebrate smooth muscle caveolae or striated muscle T-tubules and that the vesicles are the corresponding sarcoplasmic reticulum is discussed. The occurrence of such structures in molluscan muscle and elsewhere is reviewed.

Animals↗

A fluorescent probe for rapid detection of estrogen receptors.

Fluorescein conjugates to estradiol-17 beta by the sixth carbon (6-FE) and to estrone by the 17th carbon (17-FE) were used to detect estrogen receptors (ERs) in breast cancer tissue sections and in cultured cell lines (human mammary carcinoma MCF-7 and Copenhagen rat prostatic tumor R3327-AT). 17-FE was found to interact with ERs better than 6-FE by biochemical and histochemical techniques. Thin layer chromatography analysis of ethanolic extracts of 17-FE incorporated in tissues and cultured cells showed that over 95% of 17-FE was not metabolized. We concluded that the fluorescence observed in tissue sections and cultured cells was due to 17-FE and not to fluorescein dissociated from the conjugate. Analysis of 65 human breast cancer showed that 74% of the cases were positive for specific 17-FE uptake and 26% were negative. The fluorescence was consistently brighter in the ductal and glandular epithelial cells than in the stroma. specific 17-FE uptake in the nucleoli was observed in MCF-7 and in R3327-AT tumor cells in in vitro cultures, suggesting that these nucleolar estrogen receptors may play a key role in the mechanism of estrogen action. Problems of fluorescence quantitation in tissue sections and cells are discussed.

Animals↗

Regulation of neuropeptide release.

The demonstration of depolarization-induced release of substance P, Met- and Leu-enkephalin, somatostatin, neurotensin, vasoactive intestinal polypeptide and cholecystokinin-like material from various regions of rat brain in vitro supports the hypothesis that these and other neuropeptides may act as neurotransmitters. In each case the stimulus-evoked release, but not the basal release, of peptide was dependent on the presence of calcium ions in the external medium. The stimulus-evoked release of substance P from nerve terminals in rat substantia nigra may be regulated by presynaptic gamma-aminobutyric acid (GABA) receptors. The possible existence of presynaptic opiate receptors on substance P-containing sensory nerve terminals may offer an explanation for the analgesic effects of opiates at spinal cord level, and for the existence of enkephalin neurons in substantia gelatinosa. Capsaicin releases substance P from spinal cord nerve terminals and may impair their function, while having no effect on substance P neurons in supraspinal regions. The possibility of cosecretion of peptide and amine products from the same cells is discussed.

Animals↗

Malakoplakia of the lung: a report of two cases.

We have presented the clinical, radiologic and pathologic features of 2 patients with pulmonary malakoplakia. The histologic features, including diagnositc Michaelis-Gutmann bodies, were identical to those in the urinary tract where malakoplakia is recognized as an abnormal cellular response to chronic bacterial infection. Both patients were immunocompromised: one a cardiac transplant, the other a patient with Hodgkin's disease. The lesions were focal and showed some response to antibiotic therapy, although other disease processes progressed in both patients. Malakoplakia should be added to the list of unusual infections occurring at unusual sites in compromised hosts.

Heart Transplantation↗