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Biomedical subjects

D Zelterman

Publications and source records attributed to D Zelterman.

At least 37 records · Page 2Linked to original sources

Tuberculosis in physicians: compliance with surveillance and treatment.

BACKGROUND: Physicians have historically shown poor compliance with tuberculosis (TB) skin testing and treatment after infection. Studies showed that nearly one half of physicians had positive skin test results, but one half to two thirds of physicians with negative tuberculin skin test results did not undergo annual skin testing despite significant exposure to patients with TB. Compliance with chemoprophylaxis after skin test conversion was worse; only 8% to 10% of physicians with a positive tuberculin skin test result received antituberculous therapy. The Centers for Disease Control and Prevention published guidelines on prevention of tuberculosis transmission recommending that all health care workers (including physicians) comply with regular skin testing and get appropriate follow-up care. The Occupational Safety and Health Administration has adopted the guidelines as part of its strategy to prevent occupationally acquired TB. OSHA's requirement provided the opportunity to study the effect on physicians of hospital-wide attempts to apply those guidelines. No previous study has looked at the differences in compliance between physicians in training, full-time staff physicians, and part-time staff (associate physicians). Understanding these differences will enable the hospital's administration to target efforts to improve compliance with TB surveillance and medical therapy after skin test conversion. METHODS: Two hundred eighty-four physicians (189 staff physicians, 65 resident physicians, and 30 associate physicians) responded to a questionnaire that asked about demographic and professional characteristics, current status of tuberculin skin test results, and follow-up of physicians with positive skin test results. RESULTS: We found that 71% of resident and full-time physicians were current in their tuberculin skin test status, whereas 66% of associate physicians were up to date. Thirteen percent of the resident and full-time physicians had positive TB skin test results, compared with 20% of associate physicians. Female physicians had a lower prevalence of positive skin test results than did male physicians. The departments of pathology, surgery, and pediatrics had the highest prevalence of positive test results, followed by radiology, emergency medicine, and obstetrics and gynecology. Family practice and internal medicine were among the departments with the lowest prevalence of positive skin test results. Physicians obtained their skin tests from multiple sources and had their test results interpreted in multiple facilities; hence, the test procedure was not uniform. Compliance with disease prophylaxis was 55% among the resident physicians with positive Mantoux test results, 44% among the full-time staff physicians, and only 17% among the associate physicians. More than half of the physicians with positive Mantoux test results remained untreated. CONCLUSION: Physicians have unique issues in complying with TB surveillance that need to be specifically addressed by hospitals in light of guidelines enforceable by the Occupational Safety and Health Administration. Resident physicians were the most compliant with TB surveillance and treatment after infection. Staff and associate staff physicians had poor compliance with treatment. Although this study shows some improvement when compared with prior studies on physician compliance, hospital follow-up and enforcement may be necessary to bring about significant behavioral change among physicians.

Adult↗

Second solid tumors in patients with Hodgkin's disease cured after radiation or chemotherapy plus adjuvant low-dose radiation.

PURPOSE: Late solid tumors (STs) are a significant cause of morbidity and mortality in long-term survivors of Hodgkin's disease. To investigate the carcinogenic potential of two different therapeutic approaches, we measured the relative risk (RR) of STs in patients with early-stage disease cured after primary full-dose (approximately 40 Gy) radiation therapy (RT) and in patients with advanced disease who were treated with chemotherapy followed by low-dose (15 to 30 Gy) involved-field radiation (CMT). PATIENTS AND METHODS: Because therapy-induced STs generally begin after a latency period of 5 to 10 years, we restricted our analysis to patients treated before 1986 who achieved durable remissions. Patients who required salvage chemotherapy or who died of Hodgkin's disease were excluded from analysis. The RR of STs was calculated by dividing the observed number of cases by the expected number in a matched population from the Connecticut Tumor Registry. The actuarial incidence of STs was also measured. RESULTS: A total of 197 patients formed the RT group and 116 the CMT group. The median follow-up period in the RT group was 12.8 years, versus 13.5 years in the CMT group. The overall RR of STs in the CMT group was 1.5 (95% confidence interval [CI], 0.6 to 3.5; P = .122). There were no cases of lung or breast cancer. In the RT group, the overall RR of STs was 3.3 (95% CI, 2.0 to 5.3; P < .001). There were seven cases of lung cancer (RR = 10.8; 95% CI, 5.3 to 22.2; P < .001) and two cases of breast cancer (RR = 2; 95% CI, 0.6 to 7.4; P = .07). All six benign tumors occurred in the RT group. CONCLUSION: In patients cured by initial treatment for Hodgkin's disease, RT was associated with a statistically significant increase in STs, particularly lung cancer. CMT was not associated with a significant increase in STs. These data may have important implications for the design of newer therapies for early-stage Hodgkin's disease.

Actuarial Analysis↗

Survival curves subjected to occasional insults.

We describe a parametric family of survival curves which can be used to model time to event data in systems subjected to occasional insults or shocks. Parameters control the location, magnitude, and duration of the effect for each insult. We use these models to describe the survival history of a large cohort of Drosophila that were transferred to new vials on a weekly basis as their nutrient medium deteriorated. A periodic model with fewer parameters exhibits a good fit to the data.

Animals↗

Prevalence of carotid canal dehiscence in the human middle ear: a report of 1000 temporal bones.

A total of 1000 human temporal bones were used to study the prevalence of carotid canal dehiscence, microdehiscence, and thin bony coverage. Additionally, this study compares the prevalence according to sex and temporal bone age. A carotid canal dehiscence was detected in 77 (7.7%) bones. It was present bilaterally in 23.2% of the paired temporal bones. The prevalence of carotid canal dehiscence decreases with increasing temporal bone age. It was found in 10 (15.9%) bones in the younger than 2 age group, as opposed to 43 (6.3%) bones from the 40 and older group. The concept of microdehiscence of the carotid canal is introduced. A carotid canal microdehiscence was found in 74 (7.4%) bones. Microdehiscences were noted to occur bilaterally in 12.3% of the paired bones. The prevalence of carotid canal microdehiscence also decreases with increasing temporal bone age. It was detected in 7 (11.1%) bones in the younger than 2 age group, in contrast to 51 (7.5%) bones in the 40 and older group. A total of 134 (15.5%) temporal bones were found to have a thin bony coverage, without the presence of a dehiscence or microdehiscence. The prevalence of thin coverage was noted to increase linearly with age. A thin carotid canal was found in 2 (8.3%) bones from the younger than 2 age group, whereas 113 (17.3%) temporal bones from the 40 and older group exhibited this entity. To the best of our knowledge, this is the first systematic study of histologic sections of a large number of temporal bones that looks at these entities.

Adolescent↗

Piecewise exponential survival curves with smooth transitions.

Several models of a population survival curve composed of two piecewise exponential distributions are developed. In one formulation the hazard rate changes at a point that is an unobservable random variable that varies between individuals. The population hazard function may decrease with age even when all individuals' hazards are increasing. In a second formulation, the population hazard function is modeled directly. Several models are fit to the survival history of a cohort of 5751 highly inbred male Drosophila melanogaster and the British coal mining disaster data.

Animals↗

Topical CTC-96 accelerates wart growth in rabbits infected with cottontail rabbit papillomavirus.

CTC-96, a cobalt containing complex, was tested as a putative topical therapeutic agent for the treatment of papillomavirus-induced tumors in our cottontail rabbit papillomavirus (CRPV)-rabbit model system. Following experimental infection of domestic rabbits with CRPV, CTC-96 was applied to infection sites twice daily, 5 days a week for a total of 8 weeks. Two levels of concentrations of aqueous CTC-96 were compared to placebo control-treated animals. With increasing dose of CTC-96 we observed tumors earlier, larger, and more often across eight infected sites on each animal.

Administration, Topical↗

Prevalence of facial canal dehiscence and of persistent stapedial artery in the human middle ear: a report of 1000 temporal bones.

A total of 1000 temporal bones were used to study the prevalence of facial canal dehiscence and of persistent stapedial artery in detail. Of the temporal bones studied, 560 (56%) contained at least one facial canal dehiscence. There was a 76.3% prevalence of bilaterality of this canal wall gap. The most common site of dehiscence was the oval window area. The concept of microdehiscence of the facial canal is introduced. One third of the temporal bones observed had a microdehiscence of the facial canal, usually located at the oval window area (74.9%) and found bilaterally 40% of the time. The authors found a 0.48% prevalence (5 out of 1045) of persistent stapedial artery. This is the first histological study of temporal bones to report a prevalence of this vascular anomaly.

Adolescent↗

Prevalence of microfissures in the human temporal bone: a report of 1000 temporal bones.

A total of 1000 human temporal bones were studied to determine the prevalence of two microfissures: 1. the one between the facial canal and the vestibule, 2. the microfissure between the round window niche (RWN) and the posterior semicircular canal (PSC). Additionally, this study compares the prevalence according to temporal bone age and sex. The microfissure between the facial canal and the vestibule was observed in 470 (47%) temporal bones, with a bilateral presence of 77.2%. The prevalence of this microfissure increases linearly with age. It was not found in any bone within the 0 to 2 age group. It was present in 3 (7.3%) bones from the 2 to 9 age group, as opposed to 374 (54.8%) bones from the 40 and over group. The microfissure between the RWN and the PSC was detected in 915 (91.5%) temporal bones. This second microfissure was found to be an overwhelmingly bilateral entity. The prevalence of this other microfissure also increases with age. This microfissure was also not present in any temporal bone within the 0 to 2 age group. It was found in 28 (68.3%) bones from the 2 to 9 age group, in contrast to 678 (99.4%) temporal bones from the 40+ group.

Adolescent↗

Generalized logistic models for low-dose response data.

We discuss a generalization of the logistic response function of the form Pr(y = 1/x) = [1 + exp(- theta - beta'x)]-alpha, where alpha > 0. This function coincides with the usual logistic response when the shape parameter alpha is equal to one. We describe the use of this model for analysing cancer rates in mice for low-dose exposure to a known carcinogen. When estimating the low-dose responses, the errors associated with extrapolation are reduced when a priori knowledge about the rates among unexposed individuals is incorporated into the fitting procedures.

2-Acetylaminofluorene↗

Symptomatic versus asymptomatic endolymphatic hydrops: a histopathologic comparison.

One of the unanswered questions in Meniere's disease research is the pathophysiology by which the classic symptoms are produced. A histopathological study was undertaken to identify the pathological features of symptomatic endolymphatic hydrops and their relationship to these symptoms. Two groups of temporal bones were examined, compared, and described. The first group was from patients with symptoms of Meniere's disease (n = 29). Temporal bones in the second group were chosen for the presence of endolymphatic hydrops and the absence of otologic symptoms (n = 13). Significant differences were noted in the severity of hydrops, the frequency of membrane ruptures, the endolymphatic duct, and coexistent pathologic conditions. Ruptures were seen in 38% of temporal bones from symptomatic patients and in only 8% of temporal bones from patients with asymptomatic endolymphatic hydrops. Based on this study and a review of the literature, the authors believe that the symptoms and findings of Meniere's disease are explained best on the basis of both chemical and physical mechanisms being operational intermittently and together.

Cochlea↗

Mechanisms of retraction pocket formation in the pediatric tympanic membrane.

The epidemiological nature of acquired cholesteatoma in children has shown that it occurs more often in the posterosuperior quadrant of the pars tensa and in the pars flaccida. This type of cholesteatoma is rarely seen before the age of 3 years, and serous otitis media is the most important risk factor for its occurrence. In an attempt to present a pathological rationale for these clinical findings, tympanic membranes from 11 temporal bones with purulent otitis media and 13 with serous otitis media were evaluated light microscopically and compared with 14 temporal bones without disease. Ages ranged from newborn to 3 years 6 months. The persistence of mesenchyme and greater inflammatory reaction observed in the pars flaccida and the posterosuperior quadrant of the pars tensa and changes in collagen and elastin observed in purulent otitis media and serous otitis media may represent a pathological rationale for the epidemiological nature of cholesteatoma in children.

Age Factors↗

Longitudinal study of psychotropic drug use by elderly nursing home residents.

In this longitudinal study of patterns of use of psychotropic drugs by a cohort of elderly nursing home residents (N = 5,752), drug use was examined upon admission, 3 months later, and at discharge/end of study. At each time point, 17% of the cohort used neuroleptics. Half of the subjects discontinued neuroleptics at each time point; however, a similar number were initiated on the drug. Benzodiazepines were used by 21%, 15%, and 15% at each of the three time points, respectively. Twice as many people were taken off benzodiazepines as initiated on them following admission. The 5% rate of antidepressant use was constant across the three time periods, although only half of those who took antidepressants upon admission were also taking them upon discharge/end of study. The amount of change due to discontinuation of these drugs and adjustment in dosage levels challenges the stereotype of the "neglected psychotropic drug user" in nursing homes.

Aged↗

Inadequate treatment of depressed nursing home elderly.

OBJECTIVE: To determine the prevalence of antidepressant drug treatment among nursing home elderly with major depression. DESIGN: Survey early and late in nursing home stay. SETTING: Sixty Medicaid/Medicare-certified skilled nursing homes. PARTICIPANTS: Admission cohort of 5,752 residents age 65 or older in 1976 through 1983. MEASURES: Chart review by nurse-abstractors of physicians' diagnoses, drug used, and alertness rating. Diagnosis of depression equivalent to DSM-III-R major depression. RESULTS: Of 868 persons with a diagnosis of depression in the medical record, only 10% were treated with antidepressant drugs. More received neuroleptics and benzodiazepines than received antidepressants, but most (52%) received no psychoactive drug at all. A subset of 258 depressed persons had positive notations in their records supporting a mental status rating of "alert and oriented." Of that subset, only 15% received antidepressants. When followed from admission to discharge or end of study the prevalence rate of antidepressant drug treatment increased by 4%. CONCLUSIONS: In the late 1970's and early 1980's, even when the primary care physician made and recorded a diagnosis of depression, most such nursing home residents remained untreated, incorrectly treated, or inadequately treated.

Aged↗

Morphologic scales and relative distances between lesions identified on Papanicolaou smears.

We fit a Gaussian-type curve to a nonmonotonic transform of initial arbitrarily given scales (pseudoscalar transform) of a two-way discrete classification table by maximizing the likelihood (entropy) and computing morphologic scales of clusters of objects identified by visual judgments. The scales give the relative distance between pairs of categories or states. Morphologic scales of histologic lesions (states) identified on Papanicolaou smears were computed from a confusion matrix consisting of 3,545 matched pairs of observations on Papanicolaou smears and colposcopically directed biopsies available from the Gynecologic Cytology Laboratory, University of Minnesota, between 1985 and 1987. The original (uncollapsed) confusion matrix consisted of eight cytologic categories and histologic states: normal plus atypical benign, reactive atypia (including condylomatous changes); mild, moderate and severe dysplasia; squamous carcinoma in situ; invasive squamous cell carcinoma; and other malignancies. The morphologic scales are expressed numerically, which reflects a degree of confusion between two diagnostic categories or states. Except for malignancies other than squamous cell carcinoma, morphologic scales of histologic states seen from cytology retained the order of clinical severity. We detected a high degree of confusion between severe dysplasia and carcinoma in situ. Malignancies other than squamous cell carcinoma fell between moderate and severe dysplasia. Such a transposition of the scales in this group containing adenocarcinoma was likely due to frequent association of adenocarcinoma with cervical intraepithelial neoplasia. Morphologic scales of cytologic categories seen from histology showed high degrees of confusion and transpositions between mild and moderate dysplasia and between severe dysplasia and carcinoma in situ.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy↗

Information, discrimination and divergence in cytology. VI. Biases and errors of measurement in small samples.

Total discrimination and total divergence have been shown to be useful measures of performance in diagnostic cytology. The sample size, Ns (observed number of cytology-histology pairs, essential components of a confusion matrix), may be small for the comparison of two or more laboratories or periodic quality control using observed values. From actual data from previous reports in this series, the best estimation of the confusion matrix of a population was obtained by fitting a Gaussian-type curve after pseudoscalar transform of ranks (row and column numbers). Small sample confusion matrices were generated by Monte Carlo simulation to 2.5 x 10(-7) resolution. To keep measurement biases within +/- 0.5 decits, we found that 100-200 samples of cytology-histology pairs were required in the best classifications of three, four and five category-states. At these sample sizes, measurement errors (standard errors) were also contained within +/- 0.5 decits. This study also confirmed that previously reported overestimated propagated errors in small samples were in fact overestimation and that their use for testing a null hypothesis was valid. The number of samples with indefinable statistics due to a zero denominator can be as high as 30% when the sample sizes are 500 for three, four and five category-state classifications. Biases due to small samples were positive for most category-states except for the optimum three category-states, in which bias changed to negative ("bias inversion"), and observed errors of discrimination and divergence paradoxically decreased as Ns decreased ("error-sample paradox") for a small sample size (Ns less than 700).(ABSTRACT TRUNCATED AT 250 WORDS)

Cytodiagnosis↗

A statistical distribution with an unbounded hazard function and its application to a theory from demography.

We introduce a statistical distribution with hazard function mu(t) proportional to (psi-t)beta-1 for 0 less than or equal to t less than psi and shape parameter beta satisfying 0 less than beta less than 1. This hazard function is suggested by a theory of aging in demography. We discuss properties of this distribution and maximum likelihood estimates of its parameters. Mixture distributions are considered to account for pooling across dissimilar populations. This model is compared with the Gompertz and generalized Pareto distributions and used to estimate a finite limit on human lifespan based on the survival of a group of female centenarians.

Aged↗

Age-related morphologic changes in the human tympanic membrane. A light and electron microscopic study.

To our knowledge, the normal changes that occur in the tympanic membrane after birth have not been described, despite several reports that their otoscopic appearance in healthy, full-term infants is different from that in adults. To provide such a description, the tympanic membranes of 54 temporal bones that had no pathologic evidence of otologic diseases, from patients aged 33 weeks' gestation to 91 years, were examined with light or electron microscopy. The changes encountered in thickness, cellularity, vascularity, collagen, and elastin indicated beyond the first year of life and into old age.

Adolescent↗