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Biomedical subjects

J J Shuster

Publications and source records attributed to J J Shuster.

At least 145 records · Page 8Linked to original sources
PubMed1987

A morphologic study of childhood lymphoma of the diffuse "histiocytic" type. The Pediatric Oncology Group experience.

Of 227 cases of pediatric non-Hodgkin's lymphoma with adequate histopathologic material for review, 72 (32%) were classified as diffuse "histiocytic" lymphoma (DHL). These cases were further divided into different morphologic subtypes according to the Lukes-Collins classification, and the National Cancer Institute Working Formulation, to ascertain whether there were any significant prognostic differences among the different subtypes. The results of our study showed that 40 patients were classified as immunoblastic lymphomas, and 32 were called large follicular center cell (FCC) tumors. Of the 40 patients with immunoblastic histology, 19 had morphologic features of the clear cell type and were interpreted as consistent with T-immunoblastic lymphomas; an additional two had polymorphous features also consistent with T-cell type: 17 had plasmacytoid features, and were morphologically classified as B-immunoblastic lymphomas; two could not be subtyped. Of the 32 patients with morphologic features of FCC lymphomas, 29 were classified as large noncleaved type, and three as large cleaved type. A clinicopathologic analysis showed that 90% of the patients obtained complete remission, and there were no significant differences in complete remission rate among the different morphologic subtypes of DHL. The estimated five year disease-free survival for all patients was over 70%, with no failure after the second year; and there were no significant differences in the disease-free survival among the different subtypes. The only clinical differences that we found, were that patients with lymphomas of FCC (large noncleaved) type were younger (P = 0.01); had less nodal involvement (P = 0.03); and had more organ involvement (P less than 0.01). We conclude that the morphologic subclassification of DHL in children currently has limited clinical prognostic significance.

Adolescent↗
PubMed1985

An analysis of the presence of Fc receptors on bone marrow lymphoblasts in acute lymphoblastic leukemia. A Pediatric Oncology Group study.

The presence or absence of the Fc receptor (FcR) on bone marrow lymphoblasts was evaluated in 279 cases of acute lymphoblastic leukemia (ALL) by member institutions of the Pediatric Oncology Group (POG). The case material was classified as follows: 19 cases of positive (greater than or equal to 20% +), 24 additional cases as intermediate (greater than or equal to 10% but less than 20%), and the remaining 236 cases as negative (less than 10%). Intermediate and positive cases were relatively equally distributed between null cell leukemia and pre-B-cell leukemia, and there were one intermediate and two positive T-cell cases. One of two cases of B-cell leukemia was also positive. There were no distinguishing clinical or laboratory characteristics which distinguished the FcR+ cases, nor was the FcR of prognostic significance within ALL as a group or within immunologically defined phenotypes.

Adult↗
PubMed1985

The influence of skeletal implants on incidence of infection. Experiments in a canine model.

We have performed experiments in 187 dogs in order to evaluate the effect of commonly used implant materials on rate of infection. We opened the femoral canal with a hand drill and awl, instilled a suspension of bacteria, and then inserted one of the implants. The implants--stainless-steel and cobalt-chromium alloys, high-density polyethylene, prepolymerized polymethylmethacrylate, and polymethylmethacrylate polymerized in vivo--were compared with no implant (control). The effect of the different implants on the incidence of infection with Staphylococcus epidermidis, Staphylococcus aureus, and Escherichia coli was compared by determining the number of bacteria required to produce infection in 50 per cent of the femora. All of the implants were significantly more likely than the controls to be associated with infection with Staphylococcus aureus. Polymethylmethacrylate polymerized in vivo was found to be significantly more likely than all other implants to be associated with infection with Escherichia coli and Staphylococcus epidermidis. In addition to evaluating all specimens bacteriologically, we carried out a histological evaluation, and found that infection was highly correlated with an increased inflammatory response for all three bacteria. However, even with this highly statistically significant correlation, the correlation was not absolute; when only limited portions of randomly selected specimens of tissue were examined, the correlation was reduced.

Animals↗
PubMed1985

Ethical issues in cooperative cancer therapy trials from a statistical viewpoint. I. A general overview.

In conducting collaborative cancer therapy trials, investigators have an obligation to answer relevant and realistic research questions, while providing the patient with quality treatment. They should participate only in well-conceived, well-designed protocols. Their patients should follow the protocol as closely as possible. Protocol violations are admissible only in extreme cases, instances in which the patient's well-being is clearly best served by this violation. The participating clinicians have the obligation to submit quality and timely data. Finally, the results of each study must be written up in such a fashion that the reader has a clear understanding of the goals and outcomes of the trial.

Biometry↗
PubMed1985

Ethical issues in cooperative cancer therapy trials from a statistical viewpoint. II. Specific issues.

Quality collaborative clinical trials cannot be run without the complete commitment of every investigator. The clinician must provide quality data and must submit the data on time. The statistical office and protocol coordinator are responsible for maintaining confidentiality and for keeping a watchful eye on the overall conduct of the study. Safety monitoring of experimental drugs or drug combinations is a central responsibility, since individual investigators generally only see the statistical reports on the study, rather than the raw data. It is critical that interim statistical reports be interpreted correctly so as not to affect accrual adversely. A separate issue discussed in this article is the answering of negative questions. Can therapy be reduced and still obtain equal efficacy? Such studies are based on sound ethical considerations, but they are hazardous since they could lead to serious worsening in cure rates.

Antineoplastic Agents↗
PubMed1982

HLA and ophthalmic disease associations: a critical review and improved method for statistical analysis.

A critical review of published ophthalmic histocompatibility antigen association studies found numerous conflicting or ambiguous reports. Methodologic errors that could account for these discrepancies were categorized into 3 groups (1) arbitrary application of statistical methods to determine significance, (2) poor sampling design, and (3) variable disease definition. Multivariate analysis, not previously applied in this area provides a more powerful tool for assessing statistical significance. A computer program using this methodology for large studies is now available.

Computers↗
PubMed1981

Statistical analysis of the rate of recurrence of herpesvirus ocular epithelial disease.

We studied prospectively the rate of recurrence of epithelial herpetic disease in patients with at least two previously documented episodes of herpes. The estimate of probable recurrence was 24.5% +/- 4.8% within 12 months and 32.9% +/- 6.5% within 24 months. We found no significant correlation between rate of recurrence and either the age or the sex of the patient. However, the length of time between the two attacks suffered before the study was significantly associated with the length of the interval between entering the study and the next recurrence. Short intervals between previous attacks tended to be associated with short intervals between future attacks, and, therefore, with a higher recurrence rate. By eliminating a given patient from the study after one recurrence, we avoided serious biasing.

Adult↗
PubMed1981

Diagnostic strategies in the management of unexplained visual loss. A cost-benefit analysis.

In the investigation of visual loss from anterior visual pathway disease, it is imperative to differentiate the infrequent compressive from the much more common noncompressive lesions. To determine how relatively low-cost, risk-free, but error-prone visual field examination (VF) and high-cost, risk-prone, but accurate CT Scan (CT) and cerebral angiography (Angio) can be cost-effectively utilized to solve this diagnostic problem, the authors have developed a decision making model for the analysis of three management strategies. The visual field examination precedes and determines the use of neuroradiologic studies in Strategy A (VF-CT-Angio), whereas it follows the neuroradiologic studies in Strategies B (CT-VF-Angio) and C (CT-Angio-VF). The visual field-determined strategy (A) proved most cost-effective, based upon an estimated 6% or lower relative prevalence of chiasmal compressive lesions, a negligible risk in delaying their diagnosis, and a sensitive method of visual field examination. At a visual field sensitivity to chiasmal defects of 84% and a specificity of 88%, Strategy A annually saves $4 million over Strategy B and $27 million over Strategy C. At lower levels of perimetric accuracy, Strategy B is the most cost-effective approach. Strategy C is never cost-effective.

Cerebral Angiography↗
PubMed1980

An evaluation of the accuracy of community-based perimetry.

We assessed the accuracy of five office-based perimetric technicians in the examination of 14 patients with prechiasmal and chiasmal defects unknown to them. A pre-test followed by two days of instruction and supervised practice; the technicians were then retested on the same patients (post-test). An independent evaluator scored their results. The identification of any field defect rose significantly (P = .039) from 69% in the pre-test to 95% in the post-test. The identification of the hemianopic configuration of a defect rose from 45% in the pre-test to 84% in the post-test (P = .11); initial identification of nasal steps was 77%, falling to 67% in the post-test. Adequate definition of extent, depth, and slope of defects was rare (5%) on the pre-test, but rose significantly (P = .032) to 57% on the post-test. The monitored patient examinations were essential for correcting recurrent flaws in technique. This study shows that such teaching efforts, including emphasis on identifying hemianopic defects, are necessary to raise visual field examination to the level of a consistently reliable diagnostic determinant.

Evaluation Studies as Topic↗
PubMed1979

Comparison of three positions for evaluating the asymmetrical tonic neck reflex.

Twenty-four males ages 8 to 11 were videotaped while being tested in three positions for the ATNR: quadruped with the head passively rotated to either side; standing with the arms outstretched and eyes closed with the head passively rotated to either side; and quadruped reflex inhibiting posture with the skull hand on the hip and the face knee off the floor and with the head actively rotated to either side. Three "expert" raters viewed the edited tape and rated each subject in each position using a protocol devised for the study. The results suggest that the quadruped reflex inhibiting posture more readily reveals the presence of the reflex when compared to the other positions, in this population of learning-disabled children.

Child↗
PubMed1978

Susceptibility of the anaerobic bacteria, group D streptococci, Enterobacteriaceae, and Pseudomonas to semisynthetic penicillins: carbenicillin, piperacillin, and ticarcillin.

Sodium piperacillin T-1220, a new semisynthetic penicillin, was tested in vitro against 297 clinical isolates of anaerobic bacteria and 669 aerobic bacteria by the conventional agar dilution method and compared with carbenicillin and ticarcillin. At a 100-mug/ml concentration the three drugs showed comparable effectiveness against the anaerobes tested. However, at 20 mug/ml, piperacillin was the most effective drug against Bacteroides fragilis, peptostreptococci, and group D streptococci. At this drug concentration only 48% of the B. fragilis strains exhibited susceptibility to carbenicillin only, 64% exhibited susceptibility to ticarcillin but 90% exhibited susceptibility to piperacillin. Similar findings were observed with peptostreptococci and group D streptococci. On a weight basis piperacillin was statistically shown to be the most effective antibiotic of the three tested against these anaerobes. At 20 mug/ml, piperacillin exhibited a statistically significant difference (P < 0.01) over carbenicillin and ticarcillin for Serratia marcescens, Escherichia coli, Klebsiella species, Klebsiella pneumoniae, Pseudomonas isolates, and Citrobacter diversus. At both 20- and 100-mug/ml concentrations, piperacillin appeared to be the most effective (calculated P < 0.01) upon Klebsiella species, K. pneumoniae, S. marcescens, and C. freundii in activity over ticarcillin and carbenicillin.

Aerobiosis↗
PubMed1978

The effectiveness of laboratory vs written examinations in an anatomy course.

This paper reports a two-year study on the methods used to evaluate 63 junior occupational therapy students in a musculo-skeletal anatomy course offered at the University of Florida. Laboratory learning processes were not significantly different compared to class learning processes as shown by test results. There was also no significant difference between laboratory and written examination scores in anatomy when compared with final grades in subsequent courses with both laboratory and lecture components. This study was undertaken because of the varying attitudes of students and faculty and their knowledge about the most efficient and productive manner in which to conduct the course. Very little research on educational methods has been completed in our profession and the validation of current methods is needed.

Anatomy↗
PubMed1977

Occupational therapy sequential client care recording system: a comparative study.

The client care record is a key document for determining standards of care in occupational therapy. The purpose of this study was to determine the effectiveness of a client care recording system for occupational therapy that combined the theoretical framework of the Developmental Analysis, Evaluation and Intervention Schedule, and the scientific method of the Problem Oriented Medical Record. The research form of the client care record was compared to a traditional client care record in current use in an occupational therapy clinic. An interdisciplinary panel of health professionals rated both the original and proposed form of the record on the variables of completeness, organization, understandability, and usefulness. The findings show statistically significant differences between the client care record based on the combined Developmental Analysis, Evaluation and Intervention Schedule and the Problem Oriented Medical Record and the currently used record system.

Child↗
PubMed1976

Joint contracture--common manifestation of childhood diabetes mellitus.

Sixty-five of 229 seven to eighteen-year-old campers with diabetes were found to have contractures of finger joints; in two thirds of affected children only the fifth finger was involved. Stiff resistance to passive finger manipulation and thickened adherent skin over the dorsa of the hands were additional features. Short stature was associated with involvement of more than one finger; the shortest youngsters also had contractures of large joints. Joint changes were independent of age, sex, age of onset of diabetes, and control of diabetes, but correlated with duration of the diabetes.

Adolescent↗
PubMed1976

Human leukocyte interferon for the prevention of recurrences of herpetic keratitis.

A double-blind clinical trial of human leukocyte interferon is in progress for assessment of the effect of this substance on recurrences of herpetic keratitis. Although human leukocyte interferon is highly effective in preventing infection in owl monkeys (protection from infection and prevention of recurrences correlate well in lower animals), there is no difference between the frequency of recurrences in placebo-treated patients and that in interferon-treated patients. Forty-nine patients have been treated with interferon, and 46 have received placebo; there have been seven recurrences (with herpes simplex virus isolated) in each group. The interferon used is highly stable both in storage in the laboratory and in clinical use. Because the titer of interferon in this study (6.4 X 10(4) units/ml) may be too low to accomplish our prophylactic needs, attempts are being made to use the material in more concentrated form.

Administration, Topical↗