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PubMed1993

Endotoxin and interleukin-1 alpha in the cervical mucus and vaginal fluid of pregnant women with bacterial vaginosis.

OBJECTIVE: The purpose of our study was to determine the concentrations of endotoxin and interleukin-1 alpha in the cervical mucus and vaginal fluid of pregnant women who either did or did not have bacterial vaginosis. STUDY DESIGN: Samples of cervical mucus and vaginal fluid were collected from women in early pregnancy who had signs of bacterial vaginosis and from healthy control subjects. The samples were analyzed for the concentrations of endotoxin and interleukin-1 alpha. In addition, wet mounts were examined for signs of inflammation indicated by increased numbers of leukocytes. RESULTS: Both endotoxin and interleukin-1 alpha occurred in much higher concentrations (p < 0.0001, p < 0.0002) in both the cervical mucus and the vaginal fluid of women with signs of bacterial vaginosis than they did in healthy control subjects. A correlation was found between the interleukin-1 alpha concentrations in the vaginal fluid and the number of leukocytes as judged by a semi-quantitative evaluation of wet mounts (p = 0.0365). The concentrations of endotoxin correlated with those of interleukin-1 alpha in both fluids (vaginal fluid, p < 0.01; cervical mucus, p < 0.01). CONCLUSION: Our study shows that concentrations of endotoxin and interleukin-1 alpha in cervical mucus and vaginal fluid of women in early pregnancy who have bacterial vaginosis are significantly higher than the corresponding levels in control subjects.

Body Fluids↗
PubMed1995

Epithelial cells in peritoneal fluid--of endometrial origin?

OBJECTIVE: Our purpose was to examine the immunohistochemical properties of epithelial cells in peritoneal fluid and to compare the staining characteristics with cells of endometrium, menstrual effluent, peritoneum, and endometriotic lesions. STUDY DESIGN: Samples of menstrual effluent, endometrium, and peritoneal fluid and biopsy specimens of endometriotic lesions and peritoneum from 16 patients were examined. Monoclonal antibodies against vimentin, cytokeratin 18 and 19, and the monoclonal antibody BW495/36, staining an epithelial marker present in endometrium and absent in peritoneal epithelium, were used. RESULTS: All but one sample of menstrual effluent and peritoneal fluid cells stained positively with antibodies against vimentin and cytokeratin 18 and 19. BW495/36 stained 14 of 16 menstrual effluent samples and nine of 16 peritoneal fluid cell samples. Endometriotic specimens showed staining with all markers. No major differences in staining properties were observed in menstrual effluent, endometrium, and peritoneal fluid cells between patients with or without endometriosis. CONCLUSION: These results support the contention of transport of menstrual detritus to the peritoneal cavity in women with patent fallopian tubes.

Ascitic Fluid↗
PubMed1993

Total nerve cell number in neocortex in chronic schizophrenics and controls estimated using optical disectors.

The total number of neurons was estimated in eight brains from chronic schizophrenic men and compared with 16 gender- and age-matched controls. The average total neocortical nerve cell number was 22.12.10(9) in schizophrenics and 22.06.10(9) in controls. The estimate of total cell numbers can not demonstrate more subtle neuronal losses of specific cell types or cell loss in specific regions, but the result does not indicate that a major cell loss in the neocortex of schizophrenics is part of the disease. The sampling scheme was based on a uniform sampling design, the counting was performed using new stereological principles and the majority of the cerebral cortex was left intact providing the possibility for resampling and further analysis.

Adult↗
PubMed1985

A review of the nursing literature on attitudes towards old people.

This paper reviews recent research in the area of nurses' attitudes towards old people. Published work is categorized into that dealing with the effects on attitudes of characteristics of the nurses being studied, characteristics of the patients, intervention programmes and related attitudes held by the nurses. British and American work is considered. Much of the published work reviewed is found to be lacking in one or more respects. These shortcomings relate to sampling, design features, measures used and data analysis. It is concluded that research in the area will need to be improved if major policy decisions concerning the care of the elderly are to be well-informed.

Aged↗
PubMed1980

Measurement of reverse triiodothyronine in dried blood spot: methodology and clinical application as a screening procedure for detection of congenital hypothyroidism.

A new sensitive radioimmunoassay method for measuring reverse triiodothyronine (rT3) concentrations in dried blood samples, designed to screen newborn infants for congenital hypothyroidism, has been developed. Paper strips are impregnated with cord blood and dried. Duplicate 5-mm diameter discs are punched from the paper strips and added directly to the radioimmunoassay reaction mixture. After incubation, bound and free hormone are separated by dextran-coated charcoal. The disc remains in the solution throughout the procedure and the assay can be completed within 24 hr. Recovery of rT3 is greater than 95% and coefficients of variation are 9.4% (intraassay) and 12.2% (interassay) at an rT3 concentration of 220 ng/dl. At very low rT3 concentrations (25 ng/dl), coefficients of variation are 14.2% (intraassay) and 18.7% (interassay). The method readily detects 12.5 ng/dl of rT3. With this paper disc method, rT3 was measured in 38 newborns and compared with serum rT3 measured in the same subjects by a standard radioimmunoassay method. The correlation between rT3 values measured in dried blood disc and in serum was very high (r = 0.918). The rT3 in dried blood discs from the cord blood of 745 normal newborns was 228.9 +/- 76.0 ng/dl (mean +/- SD). In contrast, two infants with proven congenital hypothyroidism had rT3 values of 35 and 75 ng/dl, respectively. This study indicates that rT3 can be easily measured in dried blood discs and suggests that the described method may be a useful screening procedure in a program for the detection of neonatal hypothyroidism.

Congenital Hypothyroidism↗
PubMed1995

Secretory leukocyte protease inhibitor in the cervical mucus and in the fetal membranes.

OBJECTIVE: The purpose was to determine the concentration of leukocyte elastase and SLPI in the cervical mucus plug, cervical tissue, fetal membranes, amniotic fluid and serum from pregnant women. STUDY DESIGN: Samples were analysed using radioimmunoassay, immunodiffusion, immunohistological and enzyme assay techniques. Statistical comparisons were performed by the Mann-Whitney two-sample rank sum test. RESULTS: Concentrations of SLPI and elastase in cervical tissue are significantly increased during pregnancy and after delivery. Very high concentrations of SLPI and elastase were found in the cervical mucus plug. The concentrations of SLPI and elastase in human fetal membranes are highest at the rupture site. The concentration of elastase in amnion from preterm delivery was significantly higher than in amnion from term deliveries. CONCLUSION: The high molar ratio of SLPI/elastase in the cervical mucus plug suggests that inhibition of elastase is important during normal pregnancy. The role of SLPI may be protection of the fetal membranes and cervical tissue.

Amnion↗
PubMed1995

Mixed anxiety-depression in a primary-care clinic.

To determine the prevalence and clinical significance of a mixed anxiety-depressive (MAD) syndrome in primary care, a two-stage sampling design was applied to 796 consecutive clinic attendees without known psychiatric illness. Among 78 systematically interviewed subjects, 10.3% (n = 8) had a depressive disorder alone, 12.8% (n = 10) had an anxiety disorder alone, 19.2% (n = 15) had a comorbid anxiety and depressive disorder and 12.8% (n = 10) had a combination of subsyndromal anxiety and depressive features that fulfilled either ICD-10 or our own operational criteria for MAD. Patients with MAD rated their disability as being comparable to that of patients with anxiety or depressive disorders. These findings lend support to the notion that there is a sizeable subgroup of patients in primary care who appear to be suffering from a psychiatric syndrome with an admixture of subsyndromal depressive and anxiety features. Questions about the temporal stability of MAD and preferred approaches to treatment have yet to be answered.

Adjustment Disorders↗
PubMed1993

Design of the Lung Health Study: a randomized clinical trial of early intervention for chronic obstructive pulmonary disease.

The Lung Health Study is a multicenter randomized clinical trial. Participants are smokers aged 35-60 with spirometric evidence of moderate lung function impairment. The objective of the trial is to determine whether a program of smoking intervention and use of an inhaled bronchodilator can slow the rate of decline in pulmonary function over a 5-year follow-up period. This paper describes the background, design, sample size (approximately 6000 participants), and power estimates for the trial, as well as the treatment program and the rationale for the choice of inhaled bronchodilator. Plans for analysis of changes in pulmonary function parameters and for analysis of participants' survival and smoking-related morbidity are also discussed.

Administration, Inhalation↗
PubMed1991

AIDS survey methodology with black Americans.

Unique substantive and methodological issues are involved in conducting survey research on sexual and HIV risk related behaviors among Americans of African descent. Problem conceptualization, sampling, design of instruments, mode of data collection, interviewer/respondent characteristics, community resistance, and data analysis and interpretation are discussed. The lack of survey research on sensitive health issues is noted. Possible methods for addressing these issues are drawn from the experiences of the authors in conducting national research on the general and at risk Black community populations. It is concluded that attention to these issues can substantially improve the quality of research on AIDS related behaviors on Black communities. Finally, it is suggested that behavioral theories and sophisticated methodological and analytic approaches, sensitive to the special cultural dimensions of racial/ethnic life in the United States, would contribute substantially to the scientific armamentarium needed to successfully meet the challenge of the AIDS epidemic.

Acquired Immunodeficiency Syndrome↗
PubMed1994

The relevance of drug injectors' social and risk networks for understanding and preventing HIV infection.

Focusing on the social environment as well as the individual should both enhance our understanding of HIV transmission and assist in the development of more effective prevention programs. Networks are an important aspect of drug injectors' social environment. We distinguish between (1) risk networks (the people among whom HIV risk behaviors occur) as vectors of disease transmission, and (2) social networks (the people among whom there are social interactions with a mutual orientation to one another) as generators and disseminators of social influence. These concepts are applied to analyses of data from interviews with drug injectors in two studies. In the first study drug injectors' risk networks converge with their social networks: 70% inject or share syringes with a spouse or sex partner, a running partner, or with friends or others whom they know. Qualitative data from interviews with injectors in the second study also show that the social relationships between drug injectors and members of their risk network are often based on long-standing and multiplex relationships, such as those based on kinship, friendship, marital and sexual ties, and economic activity. In the first study the vast majority of injectors, over 90%, have social ties with non-injectors. Injectors with more frequent social contacts with non-injectors engage in lower levels of injecting risk behavior. Risk settings may function as risk networks: injectors in this study who inject at shooting galleries are more likely than those who do not to rent used syringes, borrow used syringes and inject with strangers. Since the adoption of a network approach is relatively new, a number of issues require further attention. These include: how to utilize social networks among drug injectors to reduce risk through peer pressure; how to promote risk reduction by encouraging ties between injectors and non-injectors; and how to integrate biographical and historical change into understanding network processes. Appropriate methodologies to study drug injectors' networks should be developed, including techniques to reach hidden populations, computer software for managing and analyzing network data bases, and statistical methods for drawing inferences from data gathered through dependent sampling designs.

Adult↗
PubMed1989

Hepatotoxicity and renal toxicity in rats of corn samples associated with field cases of equine leukoencephalomalacia.

Currently there is no convenient bioassay to determine the potential toxicity of corn naturally contaminated with Fusarium moniliforme. A short-term bioassay would be useful for future investigations aimed at isolating as yet unidentified toxins produced by this fungus. Two groups of five male Sprague-Dawley rats were each fed one of two F. moniliforme contaminated corn samples, designated CS-1 and CS-2, that were associated with separate field cases of equine leukoencephalomalacia (ELEM). A control group, also consisting of five male rats, was fed uncontaminated seed corn. All animals survived to the end of the study and there were no apparent differences in appearance or behaviour among groups. Weight loss and irregular food consumption occurred in all groups and probably resulted from nutritional deficiencies inherent in the corn diets. Hepatocellular degeneration, necrosis and hyperplasia as well as biliary hyperplasia were found in the test groups only and were attributed to F. moniliforme. Serum transaminase and alkaline phosphatase activities in animals fed CS-1 and CS-2 for 4 wk were significantly increased compared with the controls, while serum bilirubin concentration was increased only in the CS-1 group. Tubular nephrosis was also present in the renal cortex of all animals fed CS-1 and CS-2. These effects may have been related to fumonisins B1 and B2, recently discovered metabolites of F. moniliforme, that were found in both CS-1 and CS-2. Short-term studies of this type may be useful in screening naturally-contaminated grains and other materials for hepatotoxic metabolites produced by F. moniliforme.

Animals↗
PubMed1995

Patterns of care survey results: treatment planning for carcinoma of the prostate.

PURPOSE: Treatment planning has been defined differently at various institutions to encompass tasks ranging from the initial evaluation of the patient to the delivery of the treatment as well as a more narrow view, focused primarily on isodose computation. To evaluate the impact of much of the new treatment-planning technology that has become available, it is necessary to define and develop recommended guidelines for the treatment-planning process. METHODS AND MATERIALS: The 1989 Patterns of Care Study (PCS) included questionnaires to access treatment planning practices currently in use for the entire census of oncology facilities in the United States. These questionnaires were developed by a consensus committee consisting of both physicists and radiation oncologists whose charge was to formulate a description of current treatment-planning practices. The description was based on the committee's experience and knowledge of the treatment-planning process considered to be widely available and in general use, as well as a review of the literature. From the description of the treatment-planning process, a set of guidelines for treatment planning was developed for prostate as well as each of the other disease sites included in the PCS. Data from the study defined the general structure, methodology, process, and tools used by each institution involved in the Patterns of Care Survey Study. National averages for all of the variables were calculated with weighted averages, with the weights reflecting the sample design and number of patients in the different types of facilities. The data were stratified according to academic, hospital, or free-standing facility and were compared with the Consensus Guidelines for Treatment Planning of the Prostate. DISCUSSION: Based on the consensus statement, the treatment-planning process was separated into the following categories: (a) Treatment-Planning Workup, (b) Treatment Plan Implementation, (c) Treatment Delivery, (d) Treatment Verification, and (e) Quality Assurance. The results from the survey were summarized for each category and compared with the consensus statement. CONCLUSIONS: Although there is an increasing trend toward using computed tomography (CT) information to acquire individualized patient data, volume definition and localization are often completed in the simulator without the direct use of CT information (47%). As more sophisticated beam arrangements and blocking are used, one needs to look at the full three-dimensional (3D) volume to ensure that there are no marginal misses due to blocking and beam arrangement. Improved and more widespread use of immobilization devices is also required with conformal treatments and reduced margins. The results of the survey helped to identify and establish the standard of practice for treatment planning of the prostate as well as to provide documentation for better defining a complete description of the treatment planning process. Well-documented guidelines will provide more consistent treatment of patients, which should have an impact on outcome.

Clinical Protocols↗
PubMed1993

A comparison of alcohol consumption between lesbians and heterosexual women in an urban population.

An elevated rate of alcohol problems is believed to exist in the gay and lesbian community. However, prevalence estimates suggesting this have generally been based on convenience samples which have over-represented bar patrons and clinical sources. Recent epidemiological studies examining risk factors for AIDS have gathered information on alcohol consumption as well as sexual orientation. Data based on improved sampling methods are now available for estimating drinking rates of lesbians and gay men. This study compares the drinking patterns of heterosexual women and lesbian/bisexual women who were recruited through a random sampling design in San Francisco, CA. Contrary to previous research, no statistically significant differences in alcohol consumption and drinking patterns between these two groups were found.

Adolescent↗
PubMed1986

A bioavailability study of two preparations of tamoxifen after single doses.

The bioavailability of two different tablet formulations of tamoxifen was studied in twelve healthy male volunteers. Two tablets, each of 10 mg, of both preparations were administered orally at intervals of two weeks in a randomized cross-over design. Samples of blood for tamoxifen measurement were taken for up to 48 h following administration. Tamoxifen was measured by an HPLC method sensitive to 2.0 ng ml(-1). The area under the concentration-time curve was similar for both preparations. The study, therefore, did not demonstrate any differences between the bioavailability of the two preparations of tamoxifen.

Journal Article↗
PubMed1988

Estimation of test error rates, disease prevalence and relative risk from misclassified data: a review.

We review methods for the analysis of categorical clinical and epidemiological data, in which the observations are subject to misclassification. Under certain conditions, it is possible to estimate error parameters such as sensitivity, specificity, relative risk, or predictive value, even though no definitive classification (gold standard) is available. The parameter estimates are obtained by modelling the data, using maximum likelihood, with or without some constraints. The models recognize that the true classification of an individual is unknown, and so are sometimes referred to as "latent class" models. The latent class approach provides a unified framework for various methods found in a dispersed literature, characterising each by the number of populations or subgroups in the data, and the number of observations made on each individual; the statistical degrees of freedom are implied by the sampling design. Data sets with less than three replicate observations per individual necessarily require constraints for parameter estimation to be possible. Data sets with three or more replicates lead directly to estimates of the misclassification rates, subject to some simple assumptions. Some more complex problems are also discussed, including data where the response variable has more than two levels, sequential and irregular designs and the effects of assumption violations.

Classification↗
PubMed1995

Incidence of pulmonary tuberculosis in Korean civil servants.

SETTING: Longitudinal epidemiological study based on civil servants in Korea. OBJECTIVE: To estimate the incidence of pulmonary tuberculosis (PTB) for the general population from a reliable sample. DESIGN: New active PTB developing between 1988 and 1990 in civil servants has been determined from (1) the findings of biennial medical examinations and (2) perusal of the medical records of those claiming health insurance for tuberculosis (TB). RESULTS: A total of 790,204 subjects was available for investigation. Active PTB was diagnosed in 5107 patients over the 2 years of the study. Bacteriological examination of 3847 patients yielded 575 (14.9%) positive smears and 350 (9.1%) smear-negative positive cultures from them. Applying these rates to the 1260 whose sputum was not examined, 702 were smear-positive, and 431 were culture-positive. Overall PTB incidence was 393 per 10(5), with 84 and 53 per 10(5) smear- and culture-positive. Incidence was high in males, and in the age group 20-29 years in both sexes. CONCLUSION: Such high PTB incidence, particularly in the age group 20-29, clearly indicates that TB in Korea remains a serious health problem.

Adolescent↗
PubMed1994

Alcohol consumption during pregnancy and infant birth weight.

Heavy maternal alcohol consumption during pregnancy has been consistently linked to decreased infant birth weight but the effects of low and moderate levels of drinking on infant birth weight remain unclear. This study addresses the relationship of low to moderate alcohol consumption and birth weight in a nationally representative cohort sample (National Longitudinal Survey of Youth, n = 4409 births). Statistical methods that account for the complex sample design were used in the analysis. Multiple linear regression and logistic regression were used to adjust the relationship between drinking and birth weight for relevant covariates. Results of this study revealed a nonstatistically significant trend in the direction of greater numbers of low-birth-weight babies born to mothers who drank more frequently during pregnancy. A significant interaction between drinking and smoking was found in which the negative effects on birth weight of smoking were less for those women who drank more heavily (P = 0.046).

Adolescent↗