Biomedical subjects
Publications and source records attributed to M Bravo.
The authors prospectively examined the prevalence of somatization symptoms among community respondents after a natural disaster in Puerto Rico. Exposure to the disaster was related to a higher prevalence of medically unexplained physical symptoms, particularly gastrointestinal ones (abdominal pain, vomiting, nausea, excessive gas) and pseudoneurological ones (amnesia, paralysis, fainting, unusual spells/double vision).
Compared mental health characteristics of island Puerto Ricans to three groups from the Los Angeles Epidemiologic Catchment Area Study: Mexican American immigrants, U.S.-born Mexican Americans, and Non-Hispanic whites. The Diagnostic Interview Schedule was used to obtain both diagnostic and symptom scale information about affective disorders, alcohol abuse/dependence, somatization, phobic disorder, and psychotic disorder. Mexican American immigrants had the fewest mental health problems of all groups. Puerto Ricans had more somatization disorder, but less affective and alcohol disorders than U.S.-born Mexican Americans or non-Hispanic whites. Results are considered in the light of selection factors, relative disadvantage of groups and methodological problems.
The chromosomal sensitivity to the spontaneous and induced DNA damage detected in lymphocytes from patients affected with ataxia telangiectasia (AT) might be related with disturbances in DNA repair mechanisms. We have studied the effect of caffeine, an inhibitor of G2 repair and the enlargement of G2 by 0.5 ug/ml cycloheximide on chromosomal aberration frequencies in AT lymphocytes, both in control and X-ray irradiated conditions. The increase of spontaneous and X-ray induced chromosomal aberrations by caffeine treatments during G2 in AT lymphocytes was higher than in control cells. The number of spontaneous and X-ray induced lesions repaired during G2 in AT cells was higher than in normal cells. The enlargement of G2 duration by 0.5 ug/ml cycloheximide decreased the spontaneous and X-ray induced chromosomal aberrations in AT cells, whereas no such effect was observed in control cells. We postulate that disturbances in the mechanism that control G2 duration might be involved in the high frequency of spontaneous and induced chromosomal aberrations detected in AT lymphocytes.
The advent of the use of structured interview schedules that generate psychiatric diagnoses in epidemiologic studies has promoted an intense interest in its cross-cultural use. However, the valid use of these instruments across cultures requires a careful adaptation process which goes beyond mere language translation. In this article the authors illustrate the application of a comprehensive cross-cultural adaptation model to both the translation into Spanish and the adaptation to the population of Puerto Rico of a widely used psychiatric epidemiologic research instrument: the Diagnostic Interview Schedule (DIS). The process aimed to ensure the development of a research instrument that is not only in correct Spanish and comprehensible for most Spanish-speaking people, but also culturally adapted to Puerto Rico's population. Various steps were taken (including bilingual committee, back-translation, instrument testing and diagnostic comparisons) to address cross-cultural validity in five important dimensions (i.e., semantic, technical, content, criterion and conceptual equivalence). The result is an interview schedule that is not only linguistically and culturally adequate for the targeted population but also includes elements which can contribute to the development of the instrument both in its original English language and in its translated versions.
The production of platelet-derived growth factor (PDGF) was studied in small cell lung carcinoma, lung squamous carcinoma and lung adenocarcinoma cell lines, and in seven human lung tissues obtained from each type of lung cancer. By indirect immunofluorescence, PDGF was detected in all the cell lines. Likewise, five out of seven biopsies derived from patients with adenocarcinoma and squamous carcinoma, and four out of seven specimens with small cell carcinoma displayed a positive pattern for PDGF. In addition, lung carcinoma cell lines expressed both PDGF-A and PDGF-B/sis genes, as judged by Northern blot analysis. Biologically active, serum-free conditioned media obtained from all three cell lines stimulated the incorporation of [3H]thymidine into quiescent BALB/c-3T3 cells. This effect was abolished when IgG-PDGF antiserum was used. These findings suggest that an abnormal expression of PDGF occurs in the three more frequent types of lung cancer, which can play a potential role in neoplastic transformation and uncontrolled cell growth.
The relationship between parental alcoholism and risk for maladjustment in the offspring was investigated in a community sample. Children of parents who met criteria for DIS/DSM-III alcohol abuse or dependence and children of parents who met criteria for ten other diagnoses were compared to children of "normal" parents. The data were obtained from the merging of the data banks of two major psychiatric epidemiology studies of the adult (17-64) and child (4-16) population of Puerto Rico. Results indicated that parental alcoholism in addition to creating an adverse family environment had an effect on the relative risk for maladjustment in the offspring (as measured by scores on the Child Behavior Checklist). Although previous studies have reported higher levels of externalizing behaviors in children of alcoholics, an increased risk for internalizing symptoms was observed in the children studied. Similar findings were obtained for the children of parents with other psychiatric disorders suggesting that the effects of parental alcoholism in children ages 4 to 16 may not be different from the consequences of parental mental illness per se.
In this article we examine the role of the family in the provision of social support by studying the identity of persons which the participants consider available for providing support. We define social support as that human relationship in which socio-emotional (closeness, intimacy counseling), instrumental (goods and services) and recreational (companionship for recreation) resources are interchanged. Based on a probabilistic sample of the adult (17-68 yrs.) population, 912 persons were successfully interviewed (response rate = 90.4%) using a structured interview schedule. Results indicate that close relatives (parents, brothers/sisters, sons/daughters) are the main resource of all types of support, not only of the general population but also of specific demographic groups defined by their gender, age (17-39, 40-68) and schooling (0-11, 12 + yrs). The marital partner was also identified as an important support resource, especially emotional and recreational; more distant relatives were also important for providing instrumental support. Although the compared groups showed many similarities, they also differed in various aspects both when individually and jointly analyzed. It is concluded that the family is very important in the provision of social support in Puerto Rico (PR).
As part of a major study on the prevalence of mental disorders in Puerto Rico, this paper describes the mental health care utilization patterns of persons with a DIS/DSM-III disorder within the last year. The main findings of this analysis show that (a) There is a high rate of health service utilization, (b) The public sector is the main provider of services, (c) People with a DIS disorder tend to resort to the non-psychiatric physician, (d) People with alcohol abuse and/or dependence tend to use the services of general practitioners while schizophrenics, somatizers, and people with cognitive impairment tend to apply for the services of mental health specialists. Seeking help from other sources such as clergymen or spiritualists does not substitute the use of health services.
The Composite International Diagnostic Interview (CIDI), written at the request of the World Health Organization/US Alcohol, Drug Abuse, and Mental Health Administration Task Force on Psychiatric Assessment Instruments, combines questions from the Diagnostic Interview Schedule with questions designed to elicit Present State Examination items. It is fully structured to allow administration by lay interviewers and scoring of diagnoses by computer. A special Substance Abuse Module covers tobacco, alcohol, and other drug abuse in considerable detail, allowing the assessment of the quality and severity of dependence and its course. This article describes the design and development of the CIDI and the current field testing of a slightly reduced "core" version in Puerto Rico. The field test was being conducted in 19 centers around the world to assess the interviews' reliability and its acceptability to clinicians and general people in different cultures and providing data on which to base revisions that may be found necessary. In addition, questions to assess International Classification of Diseases, ninth revision, and the revised DSM-III diagnoses are being written. If all goes well, the CIDI will reliably allow investigators to assess mental disorders according to the most widely accepted nomenclatures in many different populations and cultures.
Anti-cardiolipin antibodies have been recently described in patients with systemic lupus erythematosus and other autoimmune disorders. Venous and arterial thrombosis, thrombocytopenia and recurrent abortion have been associated to the presence of these antibodies. Among 161 patients with systemic lupus we found 66% with anticardiolipin antibodies, mostly IgG type. Thrombosis and thrombocytopenia were more frequent in these patients (p < 0.05), especially among those with high titers. No association was found with central nervous system involvement, recurrent abortion, antinuclear or anti-DNA antibodies nor positivity for VDRL. These results support the frequent presence of anti-cardiolipin antibodies in patients with systemic lupus and their association to thrombosis and thrombocytopenia.
As part of a major study on the prevalence of mental disorders in Puerto Rico, this paper describes the mental health care utilization patterns of persons with a Diagnostic Interview Schedule (DIS) disorder within the last year. The main findings of this analysis show that a) there is a high rate of health service utilization, b) the public sector is the main provider of services c) persons with a DIS disorder use more the non psychiatric physician d) those with alcohol abuse and/or dependence tend to use more the services of general practitioners while schizophrenics, somatizers and those with cognitive impairment use more the services of mental health specialists. The use of other resources such as clergy or spiritualists do not substitute the use of health services.
Aimed to document the psychological sequelae of a disaster in the adult (17-68 years) population of the Caribbean island of Puerto Rico, by surveying 912 persons (including 375 previously interviewed) with a Spanish version of the Diagnostic Interview Schedule. A rigorous methodology, which included both retrospective and prospective designs, was used, enabled by the occurrence of a catastrophic disaster only a year after a comprehensive survey was completed. Framed in a stress theoretical perspective, disaster effects for new depressive, somatic, and posttraumatic stress symptoms were identified, even after adjusting for demographic and methodologic factors. All the effects, however, were relatively small, suggesting that most disaster victims were rather resilient to the development of new psychological symptoms. Comparison of results with previous findings and its implications for both disaster and stress research are discussed, as well as the role of community psychologists in disaster action.
Recent evidence suggests that preattentive processing may not be limited to the analysis of simple stimulus features as previously suggested. To explore this idea a visual search task was used to test whether the shapes of several perceptual groups can be processed in parallel. Textured displays that give rise to strong perceptual grouping were used to create figures on a background. Search times for a target figure distinguished by a unique shape were found to be independent of the number of distractor figures in the display. This result indicates that perceptual groups may be processed in parallel and suggests an expanded role for preattentive processing in vision.
The relationship between parental psychopathology and risk for maladjustment in the offspring was investigated in a community sample. The children of 130 parents who met criteria for 12 DIS/DSM-III disorders were compared to the children of 235 normal parents. Significantly more children of disturbed parents were functionally impaired and had higher scores in the parent and youth Child Behavior Checklist total behavior scores as compared to children of normal parents. These associations were maintained even after accounting for an adverse family environment, suggesting a strong relationship between parental and childhood psychopathology as well as a mediating influence of environmental adversity.
Increased fibroblast replication and interstitial collagen accumulation occur commonly in the interstitial lung disease that progress to fibrosis. The processes controlling lung fibrogenesis are not completely understood, however. This study was designed to analyse the influence of T lymphocytes from lung tissue obtained at open lung biopsy from four patients with idiopathic pulmonary fibrosis and four patients with extrinsic allergic alveolitis on fibroblast proliferation and collagen synthesis in vitro. Lung T cell supernatants from patients with both diseases induced a moderate but significant inhibition of human lung fibroblast cell line growth. In contrast, there was a clear difference in the effect of T cells from the two groups of patients in relation to collagen production. Lung T lymphocytes from all four patients with idiopathic pulmonary fibrosis produced a substantial increase in collagen synthesis (from 371% to 514% of control values), whereas T cells from three of the four patients with extrinsic allergic alveolitis induced a significant decrease in collagen production (to 35%, 36%, and 43% of control values); in the fourth case there was an increase in collagen synthesis but this was lower than that seen with T cells from any of the patients with idiopathic pulmonary fibrosis. Peripheral T cells from six patients and control subjects caused a small increase in fibroblast proliferation and no change in collagen synthesis. The findings suggest that at least two types of interaction occur between lung T cells and fibroblasts in these disorders. A variable degree of inhibition of cell proliferation is observed in response to lung T cell supernatants from patients with both idiopathic pulmonary fibrosis and extrinsic allergic alveolitis; a substantial increase in collagen synthesis is triggered by lymphokines from patients with idiopathic pulmonary fibrosis.
The nitrogenase from wild-type Klebsiella pneumoniae reduces cyclopropene to cyclopropane and propene in the ratio 1:2 at pH 7.5. We show in this paper that the nitrogenase from a nifV mutant of K. pneumoniae also reduces cyclopropene to cyclopropane and propene, but the ratio of products is now 1:1.4. However, both nitrogenases exhibit the same Km for cyclopropene (2.1 x 10(4) +/- 0.2 x 10(4) Pa), considerably more than the Km for the analogous reaction with Azotobacter vinelandii nitrogenase under the same conditions (5.1 x 10(3) Pa). Analysis of the data shows that the different product ratio arises from the slower production of propene compared with cyclopropane by the mutant nitrogenase. During turnover, both nitrogenases use a large proportion of the electron flux for H2 production. CO inhibits the reduction of cyclopropene by both K. pneumoniae proteins, but the mutant nitrogenase exhibits 50% inhibition at approx. 10 Pa, whereas the corresponding value for the wild-type nitrogenase is approx. 110 Pa. However, H2 evolution by the mutant enzyme is much less affected than is cyclopropene reduction. CO inhibition of cyclopropene reduction by the nitrogenases coincides with a relative increase in H2 evolution, so that in the wild-type (but not the mutant) the electron flux is approximately maintained. The cyclopropane/propene production ratios are little affected by the presence of CO within the pressure ranges studied at least up to 50% inhibition.
Glucose intolerance is frequently found in alcoholic patients and an impaired insulin response has been documented in them. To look for alternative mechanisms that could explain this intolerance, a glucose turnover using tritiated glucose and an euglycemic glucose clamp were performed to measure the glucose production rate and peripheral insulin sensitivity, respectively. Two groups of recently abstinent chronic male alcoholic patients without evidence of liver damage were studied. The glucose turnover technique showed a higher basal glucose production rate in alcoholics, compared with normal volunteers (2.83 +/- 0.29 vs. 1.84 +/- 0.22 mg/kg/min); an intravenous ethanol load significantly increased this rate. The euglycemic glucose clamp did not show peripheral insulin resistance in alcoholics, compared with controls.
Prostate carcinoma cell lines DU-145 and PC-3 express both platelet derived growth factor (PDGF)-1 and PDGF-2/sis genes. Concomitantly, these cells synthesize and secrete PDGF-like proteins, as judged by indirect immunofluorescence and by direct immunoprecipitation with specific PDGF antiserum. Conditioned media derived from DU-145 and PC-3 cells stimulated the incorporation of [3H]thymidine by 3T3 cells and competed with 125I-labeled PDGF for its binding to cell surface receptors of 3T3 cells. The biological activity was stable to heating at 100 degrees C for 10 min, sensitive to reducing agents, and neutralized by the IgG fraction of PDGF antiserum, properties similar to those of authentic PDGF. Both DU-145 and PC-3 cell lines appear to lack receptors for PDGF as indicated by their inability to mitogenically respond to PDGF and receptor binding of 125I-labeled PDGF. Production of PDGF-like proteins by human prostate carcinoma cells may play an important role in a paracrine mode in the organization of the extracellular matrix of the malignant tissue.