PubMed Health⌕ Search

Biomedical subjects

T J Long

Publications and source records attributed to T J Long.

13 recordsLinked to original sources
PubMed1998

Transfusing platelets 2 h after the completion of amphotericin-B decreases its detrimental effect on transfused platelet recovery and survival.

Platelet transfusion support is required during bone marrow aplasia following ablative chemotherapy and bone marrow progenitor cell transplantation (BMT). Amphotericin-B is frequently given to these patients, both therapeutically and prophylactically, and has been described to have a negative impact on the results of platelet transfusions. We conducted a prospective study of the effect of amphotericin-B on transfused platelet recovery and survival in 81 BMT or acute leukaemia patients. One hundred and ninety-five platelet transfusions administered to 81 consecutive patients were analysed. The platelets were transfused 2 h after the completion of amphotericin-B. Using this schedule resulted in no effect of amphotericin-B on platelet recovery or survival, although platelet increments were modestly depressed in patients receiving high- vs. low-dose amphotericin-B. We conclude that the timing of amphotericin-B infusion be evaluated in patients demonstrating poor platelet recovery and survival. Transfusing platelets at least 2 h after the completion of amphotericin-B decreases the detrimental effect of this antifungal agent on transfused platelet recovery and survival.

Amphotericin B↗
PubMed1988

An evaluation of the genotoxic potential of glyphosate.

The potential genotoxicity of glyphosate, the active ingredient in Roundup herbicide, was tested in a variety of well-established in vitro and in vivo assays including the Salmonella typhimurium and Escherichia coli WP-2 reversion assays, recombination (rec-assay) with Bacillus subtilis. Chinese hamster ovary cell gene mutation assay at the hypoxanthine/guanine phosphoribosyl transferase gene locus, hepatocyte primary culture/DNA repair assay, and in vivo cytogenetics assay in rat bone marrow. No genotoxic activity was observed in the assays performed. The data suggest that glyphosate should not pose a genetic risk to man.

Animals↗
PubMed1987

Coccidioidomycosis in adolescents presenting as chest pain.

Chest pain is a relatively common complaint in adolescents and is most often attributed to anxiety or musculoskeletal conditions. Pleuritic chest pain in association with fever and cough are frequently reported in adults with primary pulmonary coccidioidomycosis. We describe three cases in which chest pain mimicking costochondritis was the predominant initial presenting symptom of pulmonary coccidioidomycosis. In addition, in each case, recent tuberculin skin test reactivity complicated the diagnostic assessment and treatment. We conclude that, in endemic areas, coccidioidomycosis should be considered in the differential diagnosis of acute chest pain in teenagers as well as in adults.

Adolescent↗
PubMed1987

Anorexia nervosa.

Anorexia nervosa is a complex neuroendocrine-psychiatric illness that affects adolescents; its origins and pathophysiology are still poorly understood. The typical psychologic and physiologic characteristics of the illness are discussed, and the multidisciplinary team approach to diagnosis and management is outlined.

Adolescent↗
PubMed1987

Routine screening tests for the adolescent.

Routine preventive health examinations for adolescents should be conducted annually, and screening tests are an important part of such periodic evaluations. This article outlines the recommended screening tests for all teenagers, and defines the additional screening tests necessary for high risk youth. Annual health screening interventions serve to encourage the development of health-promoting behaviors and preventive health awareness among adolescents.

Adolescent↗
PubMed1985

Goiter in pregnant teenagers.

Enlargement of the thyroid gland is common in adolescent girls, but there have been no previous reports of the frequency of goiter in pregnant teenagers. This study was undertaken to determine the prevalence of goiter in 309 consecutive pregnant adolescent patients, ages 11 to 19 years, who presented for prenatal care at the University of California (San Diego) Medical Center Teen OB Clinic. Eighteen patients (6%) were found to have a goiter. Subsequent diagnostic tests revealed that 28% of the patients had autoimmune thyroid disorders (chronic thyroiditis or Graves' disease), and the remainder had nontoxic goiters or subacute thyroiditis. Black patients had significantly more thyroid disease than Mexican-American (p less than 0.01) or white patients (p less than 0.005). The incidence of thyroid problems during pregnancy did not differ significantly from that of 600 nonpregnant teenagers who came to the general Adolescent Medicine Clinic for other health problems. Because abnormalities in thyroid function may have potentially adverse implications for mothers and their infants, we recommend careful evaluation of all pregnant teenagers with goiter to assess maternal thyroid function and to provide treatment if necessary.

Adolescent↗
PubMed1977

Purification and properties of debranching enzyme from dogfish muscle.

Glycogen debranching enzyme (4-alpha-glucanotransferase amylo-1,6-glucosidase, EC 2.4.1.25 + 3.2.1.33) was purified 140-fold from dogfish muscle in a rapid, high-yield procedure that takes advantage of a strong binding of the enzyme to glycogen, and its quantitative adsorption to concanavalin A-Sepharose only when the polysaccharide is present. The final product was hrophoresis in the presence and absence of dodecyl sulfate. A molecular weight of 162,000 +/- 5000 was determined by sedimentation equilibrium analysis in good agreement with the value of 160,000 estimated by gel electrophoresis, but a low-sedimentation constant of 6.5 S suggests that the enzyme is asymmetric. The molecule appears to be made up of a single polypeptide chain with no evidence for multiple repeating sequences: it could not be dissociated into smaller fragments by dodecyl sulfate even after complete carboxymethylation; tryptic cleavage of the native protein yielded only two fragments of molecular weight 20,000 and 140,000 without loss of enzymatic activity. The amino acid composition of the enzyme is reported; no covalently bound phosphate or carbohydrate could be detected. All 32 sulfhydryl groups present were titrated with 5,5'-dithiobis(2-nitrobenzoic acid) under denaturing conditions; eight reacted readily in the native enzyme without loss of catalytic activity, while substitution of eight additional ones lowered the activity by 50%. Inactivation was greatly reduced by glycogen; the polysaccharide also influenced markedly the electrophoretic behavior of the enzyme and large filamentous aggregates were formed when solutions of both were mixed. Purified debranching enzyme releases 3 mumol of glucose min-1 mg-1 at 19 degrees C, pH 6.0, from a glycogen limit dextrin and one-tenth this amount when the native polysaccharide is used as substrate; glycogen is quantitatively degraded in the presence of phosphorylase. None of the usual sugar phosphates or nucleotide effectors of glycolysis affected enzymatic activity. No phosphorylation by either dogfish or rabbit skeletal muscle protein kinase or phosphorylase kinase could be demonstrated, nor any direct interaction with phosphorylase as measured by SH-group reactivity, enzymatic activity, or rate of phosphorylase b to a conversion. Purification of the 160,000 molecular weight M-line protein of skeletal muscle resulted in the quantitative removal of debranching enzyme, indicating that the two proteins are different.

Amino Acids↗