Search PubMed⌕ Search

Biomedical subjects

J Morgan

Publications and source records attributed to J Morgan.

At least 253 records · Page 14Linked to original sources
PubMed1985

Growth factor-mediated tumor cell proliferation in hairy cell leukemia.

Leukemic B cells from seven patients with hairy cell leukemia (HCL), six of which contained the Tac antigen, were assayed in vitro for growth factor-mediated cell proliferation. The HCL cells showed typical phenotypic profiles by monoclonal antibody analysis. The tumor cells, which do not grow spontaneously in vitro, were found to proliferate in all but one case in response to partially purified B cell growth factor (BCGF) without anti-mu or Sac activation. Recombinant interleukin 2 however produced only a marginal response and could not support leukemic cell growth in vitro. BCGF, however, did stimulate in vitro cell growth and supported the establishment of continuous (greater than 60 d in vitro) in four of the seven HCL cases.

Antigens, Neoplasm↗
PubMed1985

Chlordiazepoxide attenuates response suppression induced by corticotropin-releasing factor in the conflict test.

The role of corticotropin-releasing factor (CRF) in mediating the stress response was studied using a behavioral test in which anxiety or conflict influence performance. Rats implanted with intraventricular cannulae were tested in a Geller-Seifter conflict test modified for incremental shock. CRF produced a dose-dependent attenuation of punished and nonpunished responding in the conflict test. Chlordiazepoxide increased punished, but not unpunished, responding and produced a dose-dependent reversal of CRF-induced response suppression. CRF had no effect on tail flick or hot-plate analgesia tests. The results support the hypothesis that CRF produces behavioral effects consistent with "anxiety" or an increased responsiveness to stress.

Analgesics↗
PubMed1985

Persistent lymphadenopathy associated with hypertransfusion in sickle-cell disease.

We report the results of an immunologic evaluation of two hypertransfused (HT) patients with sickle-cell disease (SCD) who have developed persistent generalized lymphadenopathy. In order to interpret the results of this evaluation, we studied seven other HT patients with SCD and seven nonhypertransfused patients with SCD. Patients with SCD had decreased percentages of T-lymphocytes to include both helper and suppressor subsets in their peripheral blood. These decreases resulted in T helper/suppressor ratios not different from those of healthy normal control subjects. Lymphocyte proliferative responses to mitogen were decreased in the nonhypertransfused group, whereas mononuclear cell populations from both patient groups had higher levels of spontaneous suppressor cell activity than did control subjects. The patients with lymphadenopathy were distinguished from other HT sickle-cell anemia patients by immunologic abnormalities that included decreased percentages of T4+ lymphocytes, decreased T helper/suppressor ratios, and decreased lymphocyte responses to mitogen. Furthermore, the serum of these patients contained antibody specific for human T cell lymphotropic virus type III (HTLV-III). We believe that these two patients have developed acquired immunodeficiency syndrome-related lymphadenopathy as the result of transfusion-acquired HTLV-III. We propose that hypertransfusion treatment in SCD, possibly in association with phenytoin administration, places individuals at risk for HTLV-III-associated syndromes.

Adolescent↗
PubMed1985

The effect of vitamin A supplementation on serum retinol and retinol binding protein levels.

A randomised double blind controlled trial was conducted to see whether vitamin A supplementation in the form of retinyl palmitate would increase the concentrations of serum retinol and retinol binding protein. A total of 376 people were studied and were allocated to one of 7 regimens covering doses of vitamin A from O (placebo) to 36,000 IU daily. Supplementation continued for 6 months and blood samples were collected immediately before the start of supplementation, after 3 months and after 6 months. There was a small but statistically significant increase in serum retinol levels associated with supplementation, but no significant increase in serum retinol binding protein. The extent of the increase in serum retinol was related to the extent of the supplementation. On average, for every 10,000 IU of retinyl palmitate per day, the serum retinol concentration increased by 13 micrograms/l after 3 months (an increase of 2%) and 12 micrograms/l after 6 months of supplementation (2% increase). All the regimens used showed no evidence of toxicity other than minor symptomatic and physical changes affecting the skin and mucous membranes.

Adult↗
PubMed1985

Purification of human B cell growth factor.

Human B cell growth factor (BCGF, 12,000 to 14,000 daltons) has been purified from lectin-stimulated, peripheral blood mononuclear cell-conditioned medium. The purification procedure involves a series of column chromatographic steps incorporating ion exchange, affinity binding, and gel filtration. This procedure is centered around a relatively high yield single chromatographic step, for the removal of co-eluting cytokines from BCGF, that is based on differential binding characteristics to the weak ion-exchange matrix, hydroxylapatite. Reverse-phase high-pressure liquid chromatographic separation on a C18-Bondapak column effectively separates the BCGF and TCGF moieties, yet is characterized by poor yields. High-pressure liquid chromatographic procedures on anion exchange and size exclusion provided the final purification step for BCGF, at an analytical level, resulting in a single band with a m.w. of 12,000 on a SDS-polyacrylamide gel.

Chromatography, Affinity↗
PubMed1984

Dying of cancer. Factors influencing the place of death of patients.

An analysis of factors influencing the place of death of patients seen by two medical oncology units is reported. There were 1295 recorded deaths of patients from the Royal Prince Alfred Hospital, Sydney, and 688 from The Royal North Shore Hospital of Sydney during 1979-1981; the places of death were known in 1724 instances (87%). Of these, 73% of patients died in hospital, 9% died in terminal nursing care (TNC) institutions, and the remainder at home. Factors influencing the place of death were the place of residence, age, home circumstances-social support, diagnosis, and interval from first contact with the medical oncology unit. Our data indicate that a complex interrelation of these factors determines the place of death. Improvements in community services may allow more patients with cancer to die at home or in TNC institutions, but a substantial proportion of these will still die in major hospitals. Therefore, there is a need for the improvement of palliative care services in these institutions.

Adult↗
PubMed1984

Age at clinical onset and at ultrasonographic detection of adult polycystic kidney disease: data for genetic counselling.

Few reports are available on the age-related risk of relatives of affected persons to manifest adult polycystic kidney disease (APKD). For 371 persons in 17 kindreds, at risk for APKD by virtue of having an affected first degree relative, we calculated the estimated probability of clinical diagnosis of APKD to be 0.011 by age 20, 0.041 by age 30, 0.115 by age 40, 0.299 by age 50, and 0.404 by age 60 years (expected = 0.50). Ultrasonographic examination of 172 asymptomatic persons at risk showed definite APKD in 60. The probability of ultrasonographic detection of asymptomatic APKD is estimated as 0.222, 0.657, and 0.855 at age 5, 15, and 25 years, respectively. The probability of having APKD following normal ultrasonogram results (conservatively assuming 90% specificity) is estimated as 0.46, 0.28, and 0.14 for persons at 50% risk in their first, second, or third decade. The marginal benefit of ultrasound as a diagnostic test for APKD for persons in the second or third decade is estimated as 0.37 and 0.41, respectively for a "positive" test and 0.22 and 0.37 for a "negative" test.

Adolescent↗
PubMed1984

Efficacy of topical antibiotic therapy in acute conjunctivitis in children.

We studied 102 children aged 1 month to 18 years in a randomized, double-blind trial designed to determine both the natural history of bacterial conjunctivitis and whether topical antibiotic therapy is beneficial. Affected eyes were treated four times a day for 7 days with drug (polymyxin-bacitracin ophthalmic ointment) or placebo. Eighty-four patients had proved bacterial conjunctivitis (Haemophilus influenzae 61, Streptococcus pneumoniae 22, both one); 66 of these received only topical therapy. By 3 to 5 days, 21 of 34 (62%) patients receiving topical antibiotic were clinically cured, whereas only nine of 32 (28%) patients given placebo were cured (P less than 0.02). By 8 to 10 days, 31 (91%) of the patients given antibiotic and 23 (72%) of the placebo group were cured (P = NS). The bacterial pathogen was eradicated by day 3 to 5 in 71% and by day 8 to 10 in 79% of patients given antibiotic, compared to 19% and 31% of the placebo group (P less than 0.001). Acute bacterial conjunctivitis is a self-limited disease, but topical antibiotic therapy with polymyxin-bacitracin shortens the duration of clinical disease and enhances eradication of the causative organism from the conjunctiva.

Acute Disease↗
PubMed1984

Prognosis of adult onset polycystic kidney disease re-evaluated.

To appraise the prognosis of adult onset polycystic kidney disease (APKD), an inception cohort containing 140 subjects from 17 kindreds was assembled. Multiple renal cysts, demonstrable by ultrasonography, or clinical APKD, or both were present in 100 subjects. APKD was predicted in 32 subjects unavailable for ultrasonography and could not be excluded in eight deceased subjects. All had been at risk for endstage renal disease (ESRD) since birth. The probability of either developing ESRD, requiring dialysis or transplantation, or dying was estimated using a time-to-event analysis. The earliest age at which ESRD occurred was 36 years. For those with APKD, the probability of being alive and not having ESRD was 77% by age 50, 57% by age 58, and 52% by age 73 years. Excluding those predicted to have APKD changes these probabilities to 75, 53, and 47%, respectively. The serum creatinine values were less than 1.5 mg/dl for most subjects who had not developed ESRD. The prognosis for subjects with APKD is much better than most reports suggest and can be estimated from the time-to-event data presented.

Adult↗
PubMed1984

Evidence for an intracellular precursor for human B-cell growth factor.

Human B-cell growth factor has been described as a trypsin-sensitive protein of Mr 12,000-14,000. Evidence is provided herein that this relatively low molecular weight product may be released from a larger precursor molecule of Mr 60,000-80,000. The precursor protein is confined to the cytosol of freshly isolated T lymphocytes, and only the Mr 12,000-14,000 moiety is released upon lectin stimulation. The precursor protein was subjected to limited tryptic digestion, which demonstrated that the biologically active fraction of the moiety resided in a relatively low molecular weight fragment. The T lymphocyte routinely possessed an intracytoplasmic pool of the precursor protein, the amount of which cyclically varied depending upon its depletion by the secretion process of a lower molecular weight product. Analysis of the mRNA size coding for the majority of B-cell growth factor activity, determined by translation in Xenopus laevis oocytes, suggested that the B-cell growth factor-specific mRNA resided in the greater than or equal to 15S range. This value is consistent with the size of the larger precursor. Therefore, it is proposed that a precursor-product relationship exists for the processing of human B-cell growth factor, analogous to that which has been described for several other cytokines.

Animals↗
PubMed1984

HLA and urolithiasis.

Frequencies of persons having particular HLA-A, -B, and -C antigens were compared for 113 urolithiasis clinic patients, a subset of 24 patients who had hypercalcuria , and 225 controls. The frequency of HLA- A30 was significantly elevated among the patients. A suggestion (S afwenberg et al. 1978) that HLA-B27 frequency is elevated among hypercalcuric patients with recurrent kidney stones was not confirmed.

Adult↗