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Biomedical subjects

S Long

Publications and source records attributed to S Long.

101 records · Page 6Linked to original sources
PubMed1980

Mitral valve vegetations in bacterial endocarditis resembling left atrial myxoma.

A patient with Staphylococcus aureus endocarditis is reported whose echocardiogram closely resembled that found in left atrial myxoma. Because of severe mitral incompetence, the valve was replaced using cardiopulmonary bypass and at operation a large 3 cm friable vegetation was found attached to the posterior leaflet of the mitral valve. Histological examination showed changes typical of bacterial endocarditis with no evidence of myxoma.

Aged↗
PubMed1978

Autonomic receptor functions of the human ureter: an in vitro study.

The autonomic receptor functions of ureteral smooth muscle were studied in vitro on strips of human ureter obtained at surgery. A dose-dependent, reproducible, contraction response to 5-hydroxytryptamine (Serotonin, 5-HT) was demonstrated. This response could be blocked by methysergide. Responses to acetylcholine and to drugs stimulating adrenergic receptor functions were also found, but they were weak and inconsistent. This suggests that contraction of ureteral smooth muscle is mediated through receptors which are sensitive to 5-hydroxytryptamine.

Acetylcholine↗
PubMedDate not supplied

Evolution of the echinoderm Hox gene cluster.

Extant echinoderms are members of an ancient and highly derived deuterostome phylum. The composition and arrangement of their Hox gene clusters are consequently of interest not only from the perspective of evolution of development, but also in terms of metazoan phylogeny and body plan evolution. Over the last decade numerous workers have reported partial Hox gene sequences from a variety of echinoderms. In this paper we used a combined methods approach to analyze phylogenetic relationships between 68 echinoderm Hox homeodomain fragments, from species of five extant classes--two asteroids, one crinoid, one ophiuroid, one holothuroid, and three echinoids. This analysis strengthens Mito and Endo's (2000) proposition that the ancestral echinoderm's Hox gene cluster contained at least eleven genes, including at least four posterior paralogous group genes. However, representatives of all paralogous groups are not known from all echinoderm classes. In particular, these data suggest that echinoids may have lost a posterior group Hox gene subsequent to the divergence of the echinoderm classes. Evolution of the highly derived echinoderm body plan may have been accompanied by class-specific duplication, diversification and loss of Hox genes.

Amino Acid Sequence↗
PubMedDate not supplied

Comparative physiology of renal tubular transport mechanisms.

This manuscript discusses current concepts of glomerular filtration and tubular transport of sodium, water, potassium, and urinary acidification by vertebrate kidneys in a comparative context. Work in mammalian and amphibian nephrons receives major emphasis due to our interest in application of new techniques for investigation of cellular mechanisms; when available, data from other vertebrate classes are discussed.

Ammonia↗
PubMedDate not supplied

Pulmonary density distribution in experimental noncardiac canine pulmonary edema evaluated by computed transmission tomography.

We evaluated the density distribution (anterior-posterior) of the right lung in 19 acutely anesthetized supine dogs using computed transmission tomography (CTT). Eleven dogs served as controls, and eight received 0.12 cc/kg of intravenously administered oleic acid. The latter were sequentially imaged over 1 hour. Nine of these dogs (three control and six oleic acid dogs) had wet weight/dry weight ratios of the corresponding anterior and posterior lung sections evaluated immediately upon completion of the scans. In the control animals, the posterior (dependent) lung was 25 +/- 8% (+/- S.D.) denser than the anterior lung, and did not differ if a second section of the lung was evaluated (1 cm cranial or caudal), or if the animal was imaged on a second day (n = 6). In the oleic acid dogs, the posterior portion of the lung was significantly denser 10 minutes after injection of oleic acid (P less than 0.05), and almost twice as dense 1 hour after initial injection. The density changes determined by CTT in the anterior and posterior lung zones correlated well with the increasing regional wet weight/dry weight relationships determined from the lung on postmortem exam (r = 0.90). We conclude that early subtle density changes in the posterior lung can be found in oleic acid injury pulmonary edema. This can be easily quantitated using CTT, and may prove useful in following physiologic and therapeutic interventions during leaky membrane acute pulmonary injury.

Animals↗
PubMedDate not supplied

Can we increase breast feeding rates?

Breast feeding rates in Ireland have stagnated at around 33% over the past 10 years. We aimed to assess the effect of a simple intervention in late pregnancy on breast feeding rates. The study was randomised and prospective. In the intervention group a sheet illustrating eight positive aspects of breast feeding was presented to mothers at their 36 week antenatal visit. This information was reinforced with a questionnaire on the topic of breast feeding. The control group received a routine antenatal care. There were 98 mothers in the intervention group and 95 controls. A similar percentage in each group had medical cards. On discharge from hospital 31.5% of controls and 43.9% of the test group were breast feeding. This difference just failed to reach statistical significance (P = 0.07). The intervention, which took just three minutes of a medical student's time, appeared to result in an improved breast feeding rate. Though the difference did not reach statistical significance, this reflects, in part, the small numbers in the study. About half of the women in the study indicated that no doctor had offered any advice on the choice of feeding. Since this minor intervention produced a good response, it would seem appropriate to adopt a more positive attitude in the promotion of breast feeding.

Breast Feeding↗