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Biomedical subjects

J W Cochran

Publications and source records attributed to J W Cochran.

12 recordsLinked to original sources
PubMed1999

Recent developments in the high-resolution gas chromatography of polychlorinated biphenyls.

The capillary gas chromatography of polychlorinated biphenyls (PCBs) is reviewed. Focus is on the most recent developments in the separation and detection of PCBs rather than sample preparation methods. Included are a comprehensive look at stationary phases that have been used to separate PCBs and the relatively new work on chiral separations of PCBs. Mass spectrometry and atomic emission are presented as selective detection techniques. Suggestions for additional research are proposed where appropriate.

Chromatography, Gas↗
PubMed1982

Transient global amnesia after cerebral angiography. Report of seven cases.

Because of a case of typical transient global amnesia following cerebral angiography, the records of all patients undergoing cerebral angiography during a seven-year period were reviewed. Six other cases were discovered. All patients had either transfemoral catheter or brachial angiograms performed immediately before the development of amnesia. Spasm of a vertebral artery was noted in one case. None had clinically obvious seizures. All recovered within 24 hours. This only recently reported complication of cerebral angiography is consistent with a vascular etiology of the syndrome of transient global amnesia when not associated with angiography, although a direct toxic effect of the contrast material cannot be excluded.

Acute Disease↗
PubMed1979

Anti-inflammatory activity of sesquiterpene lactones and related compounds.

Some sesquiterpene lactones and related compounds were tested for anti-inflammatory activity in rodents. In the edema-induced carrageenan inflammation screen, the alpha-methylene-gamma-lactone moiety of the sesquiterpene lactones was required for inhibitory activity. The 6-hydroxy group of helenalin also was required for potency. In the tenulin series, the 2,3-epoxy derivatives were marginally active. The same structure was required for inhibition of the writhing reflex. In the chronic adjuvant arthritic screen, compounds containing the alpha-methylene-gamma-lactone moiety, the beta-unsubstituted cyclopentenone ring, and the alpha-epoxy cyclopentenone system afforded significant inhibition at 2.5 mg/kg/day. The sesquiterpene lactones were marginally effective against induced pleurisy. The delayed hypersensitivity was suppressed by these agents whereas immunoglobulin synthesis was slightly stimulated. No delerious side effects were observed with these agents from the limited tests performed.

Anaphylaxis↗
PubMed1979

Antitumor agents: structure--activity relationships in tenulin series.

Systematic structural modifications were performed on the natural sesquiterpene lactone tenulin to define those groupings essential to, or significant in, its in vivo antitumor activity. Accordingly, the following tenulin analogs were prepared: dihydrotenulin, 2,3-epoxytenulin, isotenulin, dihydroisotenulin, 2,3-epoxyisotenulin, and tetrahydrodeacetylisotenulin. Both the cyclopentenone and the hemiketal units in tenulin were necessary for high in vivo activity.

Animals↗
PubMed1979

Calcification of the basal ganglia: computerized tomography and clinical correlation.

During a 1-year period, 4219 consecutive computerized tomograms (CT) were reviewed for basal ganglia calcification; 14 patients with such calcification were identified. Calcifications on CT scan were bilateral in 12 of these cases and unilateral in 2. All bilateral calcifications were symmetric. The globus pallidus was the site of calcification in 13 of the 14 patients. Bilateral dentate nucleus calcification was seen in one patient. Skull radiograms were normal in all but one. Patients had diverse symptoms that were often explained by other findings, suggesting that calcifications may be coincidental and that basal ganglia calcification may not be a nosologic entity. Disturbances of calcium metabolism were not found in these patients, minimizing the pathophysiologic significance of altered calcium metabolism and the need for extensive endocrinologic evaluation. The finding of basal ganglia calcification alone does not justify invasive diagnostic procedures. Extrapyramidal signs may be associated with basal ganglia calcification; parkinsonism associated with basal ganglia calcification differs from idiopathic parkinsonism in being resistant to levodopa therapy.

Adult↗
PubMed1978

Reversible mental symptoms in temporal arteritis.

Mental symptoms are common in temporal arteritis. Reported here is a case in which a deficit in nonverbal memory documented with psychological testing resolved after a course of steroids. Besides the global confusional states commonly seen in temporal arteritis, focal intellectual impairment may be seen. It seems possible that some patients presenting with dementia as well as focal mental signs may have temporal arteritis. The diagnosis can easily be made by performing an erythrocyte sedimentation rate and temporal artery biopsy.

Aged↗
PubMed1978

Pancreatic pseudocyst presenting as massive hemothorax: a case report.

The case of a 36-year old man who presented with massive recurrent hemothorax as a complication of a pancreatic pseudocyst is described. Some of the complications of pancreatitis and pancreatic pseudocysts are discussed. Recurrent hemothorax represents an unusual pulmonary complication of pancreatic pseudocysts to be included in the differential diagnosis of pleural fluid collections in pancreatitis.

Acute Disease↗
PubMed1977

Hydrocortisone effects on cell proliferation: specificity of response among various cell types.

The effect of 14 micrometer hydrocortisone (HC) on the proliferative activity of various vertebrate cell lines has been measured. Such activity in human deploid cell line WI-38 was enhanced by HC addition whereas in a number of other vertebrate cell lines under identical conditions HC was inhibitory to growth. We examined the effects of HC on normal human diploid cells other than WI-38; some were stimulated, some inhibited and some were unresponsive. The results suggest that cells derived from different human tissues retain in vitro some aspects of their cell-specific hormonal responses.

Aging↗