Search PubMed⌕ Search

Biomedical subjects

J Jackson

Publications and source records attributed to J Jackson.

At least 235 records · Page 13Linked to original sources

Acute lymphoid leukemia in adolescents: clinical and biologic features predict a poor prognosis--a Pediatric Oncology Group Study.

Analysis of remission induction rates for 1,768 children (1.5 to 11 years) and 425 adolescents (greater than or equal to 11 years) with acute lymphoid leukemia (ALL), and of event-free survival times for 570 children and 147 adolescents, disclosed that adolescents fared significantly worse by both measures of treatment outcome (P = .0001). Adolescents with either T cell or non-T cell ALL entered remission significantly less often than did children (P = less than .02 and P = less than .001, respectively). Within each of the major immunophenotypes of ALL, adolescents had shorter duration of continuous complete remission: early pre-B (non-B, non pre-B, non-T) (P = .001), pre-B (P = .05), and T (P = .027). We compared the clinical characteristics of adolescents and children, and lymphoblast characteristics present at diagnosis to account for the inferior prognosis of adolescent patients. Adolescents had a higher incidence of T cell ALL (P = .0001) and thus a higher incidence of all T cell-associated characteristics. Adolescents with non-T, non-B ALL were more likely to be male (P = .044), and to have higher leukocyte counts (P = .002) and lower levels of IgG (P = .0003), IgA (P = .0001), and IgM (P = .002). Their leukemic cells had lower PAS scores (P = .0001), a higher incidence rate of L2 morphology by French-American-British (FAB) criteria (P = .001), common ALL antigen negativity (P = .0001), and hypodiploid or pseudodiploid karyotypes (P = .004). These findings clearly indicate an increased incidence of prognostically unfavorable clinical and biologic features in adolescents with ALL, providing a biologic explanation for their poor prognosis.

Adolescent↗

Appearance changes associated with participation in a behavioral weight control program.

Relationships among objectively-measured weight changes, perceived changes in weight, and perceived changes in attractiveness of participants in a behavioral weight control program were examined. Participants in the program were weighed and photographed before and after treatment and at a six-month follow-up session. These photographs were then rated on the dimensions of perceived weight and perceived attractiveness by the same participants, who were kept blind to the times at which the photographs were taken. Correlational analyses indicated that there was little correspondence between objectively-measured weight change and perceived weight changes or between objectively-measured weight change and perceived change in attractiveness. Perceptions of weight change and perceptions of attractiveness change were, however, strongly related.

Adult↗

Aldosterone responsiveness to metoclopramide in hyperprolactinaemia.

Basal serum aldosterone levels in 13 hyperprolactinaemic females did not differ significantly from those of nine control individuals. There was increased responsiveness of circulating aldosterone levels to the long acting dopamine antagonist metoclopramide (10 mg intravenously) in the hyperprolactinaemic patients as compared with the controls. Prolactin responsiveness to metoclopramide was reduced in the patients as compared with the controls, such being considered characteristic of a prolactinoma. Basal serum thyrotrophin (TSH) levels, although within the euthyroid range, were increased in the patients as compared with the controls. There was no significant difference in the TSH responsiveness to metoclopramide between the study groups. However, in the five patients with exaggerated responses of TSH to metoclopramide, basal TSH levels were significantly higher than in the other patients. One explanation for these results is that prolactin can directly or indirectly modulate the aldosterone response to metoclopramide.

Aldosterone↗

Development and validation of a radioimmunoassay for human secretory 'pregnancy-associated endometrial alpha 2-globulin' (alpha 2-PEG) and detection in serum during pregnancy.

A specific and sensitive radioimmunoassay has been developed for pregnancy-associated endometrial alpha 2-globulin (alpha 2-PEG), the major secretory protein of the human endometrium during the mid- to late-luteal phase of the menstrual cycle and first trimester of pregnancy. This assay enabled alpha 2-PEG to be measured in the cytosolic extracts of endometrium, amniotic fluid, seminal plasma and in pregnancy sera. The concentration of alpha 2-PEG in cytosols prepared from mid-secretory endometrium was 44-fold higher than in those from proliferative endometrium and a further 30-fold increase during the first trimester in comparison with mid-secretory endometrium. Levels of alpha 2-PEG in amniotic fluid (15-20 weeks) and seminal plasma were 15 +/- 4 and 55 +/- 7 micrograms/ml, respectively. With the exception of sera, where alpha 2-PEG was undetectable using rocket immunoelectrophoresis, estimates of alpha 2-PEG levels in these compartments, measured by rocket immunoelectrophoretic and RIA assays were comparable, although for seminal plasma 2.5-fold higher estimates were obtained by RIA. Detectable levels of alpha 2-PEG were obtained in 253 of 275 (92%) pregnancy sera tested. During pregnancy, peak levels were detected between weeks 6 and 11 but these represented only 2% of the levels detected in amniotic fluid. These observations support evidence from in vitro studies that alpha 2-PEG is a product of the secretory glandular epithelium, a tissue prominent in the first trimester and whose principal secretory route during pregnancy is into the amniotic fluid.(ABSTRACT TRUNCATED AT 250 WORDS)

Amniotic Fluid↗

The possible effects of a change to master's entry level in occupational therapy.

One of the most challenging debates facing the profession of occupational therapy centers on whether or not the standard for entry level into the field should be upgraded. The occupational therapy baccalaureate degree has been viewed as too limited in scope and professional training, and the master's degree has been forwarded as the standard for entry into the profession. However, upgrading the entry level standard raises several questions. This study considered 25 areas that would be affected by upgrading the entry level from the baccalaureate to the master's level in occupational therapy and in related health professions. A model was developed to provide a framework for analyzing how a change in entry level will affect the current status of occupational therapy as a profession. Although the parallel material is drawn from other health professions, the considerations are similar to the ones faced by occupational therapy. This comparison is especially important because a major change in entry level education has far-reaching repercussions that must be considered before any groundwork is laid for upgrading educational requirements.

Clinical Competence↗

Selection and acquisition of audiovisual materials by health professionals.

Audiovisual (AV) materials are widely used in the education of health professionals, and health science educators are usually the people who select audiovisual teaching materials. However, little is known about the selection process and there are few parameters that can be used for guidance. No previous research was uncovered that documented the selection/acquisition of materials by users. This paper reports a survey of health science educators and resource consultants at forty-five academic health centers in the United States, on their experiences in identifying, selecting, and using AV materials. The results provide a baseline of information on which future research can build.

Audiovisual Aids↗

Oxidant injury of cells.

H2O2 compromises a multitude of cellular functions the combination of which leads to cell death. DNA is an important target for oxidant-induced injury. The formation of DNA strand breaks leads to activation of poly-ADP-ribose polymerase (24) which in turn causes depletion of NAD and ATP, followed by Ca++ influx and eventually by cell lysis. Inhibitors of poly-ADP-ribose polymerase prevented cell lysis, but not DNA damage. A similar sequence of events has been described for cell injury following DNA damage induced by gamma-irradiation and alkylating agents, and was proposed to be a suicide mechanism for cells with irreversibly damaged DNA. Sublethal doses of H2O2 will delay cell division, but not necessarily prevent it.

Animals↗

An attempt to prevent anaphylaxis by aerosolized antigen in guinea pigs.

In an attempt to provide an alternative and safer technique of specific hyposensitization for those patients for whom the conventional treatment presents a high risk for anaphylaxis, we used a guinea pig model for extracorporeal hyposensitization. We sensitized three groups of guinea pigs with an olive pollen extract. Two of the groups were sensitized before removal of their buffy coat and the third group was sensitized after the removal of their buffy coat. The buffy coat cells were incubated with the same antigen and intracardially reinjected into their respective donors. Subsequent challenges by aerosolized antigen and intracardiac injections were performed. We did a basophil degranulation on random samples of buffy coat of tested and control animals. We skin tested the animals and we examined the histopathology of their lungs. The animals reinjected with the incubated buffy coat prior to sensitization showed a greater protection from aerosolized antigen and the onset of their anaphylactic symptoms was significantly delayed when compared with controls. The results of basophil degranulation studies showed that animals sensitized before removal of their buffy coat had approximately a threefold increase of degranulated basophils as compared with animals that were sensitized after removal of buffy coat and approximately a fourfold increase when compared with controls. This degranulation did not affect the specific skin test. Histopathologic observations did not reveal any characteristics typical of anaphylaxis.

Aerosols↗

The French-American-British (FAB) classification of leukemia. The Pediatric Oncology Group experience with lymphocytic leukemia.

The Pediatric Oncology Group institutions initiated extensive subclassification of cases of acute lymphocytic leukemia (ALL) at diagnosis into laboratory-designated categories. Included was a French-American-British (FAB) classification of all new patients, which was reviewed by a central six-member committee. In addition, on the basis of immunologic criteria, patients were defined as having T-, B-, pre-B-, or "null" cell leukemia. Slides from 617 patients were reviewed. Five hundred forty-six (88.5%) were classified as L1, 51 (8.3%) were classified as L2, 9 (1.5%) were classified as L3, and the remainder could not be assigned. Concordance within the committee was good: in 71% of the cases the committee was unanimous, and in an additional 17% only one member disagreed. In only 11 cases (1.8%) was diagreement such that a majority classification could not be assigned. Institutions assigned L2 more frequently. There was a strong correlation with L3 for B-cell disease only. However, four patients had unequivocal B-cell disease and unmistakable L1 morphologic type, whereas one and had L3 morphologic features and had non-B-cell disease. There was no correlation between the other immunologic markers or periodic acid-Schiff stain and FAB classification, nor between L1 or L2 and risk factors. However, for the 248 null cell and pre-B-cell patients, L2 was more frequent among patients in the poor-risk group (P = 0.008). The time to first failure was significantly shorter for patients with L3 morphologic type. The induction failure rate of L2 patients was significantly greater than that of L1 patients (P = 0.016). With analysis of the duration of remission and adjustment for risk factors, the impact of L2 morphologic characteristics on outcome was not significant (P = 0.18) in null cell patients. Even unadjusted for risk factors, there was no impact of L2 morphologic type on outcome in the pre-B-cell phenotype. It can be concluded that other risk factors overshadow the impact of L1 and L2 morphologic features in predicting duration of remission.

Antineoplastic Combined Chemotherapy Protocols↗

Effects of auricular transcutaneous electrical nerve stimulation on experimental pain threshold.

This study was conducted to examine the effects of high intensity transcutaneous electrical nerve stimulation at auricular acupuncture points on experimental pain threshold. Forty-five healthy adult male and female subjects were assigned randomly to one of two treatment groups or to a control group. Subjects in the two treatment groups received high intensity TENS to either appropriate or inappropriate (placebo) acupuncture points on one ear. Experimental pain threshold at the ipsilateral wrist was determined with a painful electrical stimulus before and after ear stimulation. Only the group receiving stimulation of appropriate ear acupuncture points exhibited a significant increase (p less than .01) in experimental pain threshold after ear stimulation. The comparable placebo and control groups, again, did not exhibit significant pretest-posttest differences in experimental pain threshold. The results suggest that, if applied accurately, auricular TENS can increase pain threshold. Further research is needed to assess the effects of this technique on patient groups.

Acupuncture Therapy↗

Characterization of murine monoclonal antibodies to Escherichia coli J5.

Twenty-eight independently derived monoclonal antibodies (MAb) directed against Escherichia coli J5 endotoxin were produced and characterized. Each MAb exhibited a specific titer by both radioimmunoassay and passive hemagglutination assay. Most of the MAb were of the immunoglobulin G isotype; however, several immunoglobulin M antibodies and one immunoglobulin A antibody were produced. When characterized for their capacity to cross-react with purified endotoxin preparations from several gram-negative bacteria, 22 MAb exhibited no cross-reactivity; 6 demonstrated a limited capacity to cross-react with other endotoxin preparations. When characterized for their capacity to react with the intact organism instead of the purified endotoxin the pattern of cross-reactivity was quite different. Most of the MAb were able to react with Salmonella minnesota Re595. Eighteen were able to react with E. coli O111:B4 (the parent strain of E. coli J5), 13 MAb reacted weakly with Pseudomonas aeruginosa, and 3 reacted weakly with Klebsiella pneumonia. The data imply that MAb generated against E. coli J5 endotoxin demonstrate greater cross-reactivity when assayed against the whole bacterium than when assayed against the corresponding purified endotoxin. We were unable to demonstrate that any of the 28 MAb could passively protect mice against lethal endotoxin challenge.

Animals↗