György Miklós Böhm

Assessment of the Effects of Sugar Cane Plantation Burning on Daily Counts of Inhalation Therapy

ABSTRACT This study was designed to evaluate the association between sugar cane plantation burning and hospital visits in Araraquara in the state of São Paulo, Brazil. From June 1 to August 31, 1995, the daily number of visits of patients who needed inhalation therapy in one of the main hospitals of the city was recorded and used as health impairment estimation. Sedimentation of particle mass (the amount of particles deposited on four containers filled with water) was measured daily. The association between the weight of the sediment and the number of visits was evaluated by means of Poisson regression models controlled for seasonality, temperature, day of the week, and rain. We found a significant and dose-dependent relationship between the number of visits and the amount of sediment. The relative risk of visit associated with an increase of 10 mg in the sediment weight was 1.09 (1-1.19), and the relative risk of an inhalation therapy was 1.20 (1.03-1.39) on the most polluted days (fourth quartile of sediment mass). These results indicate that sugar cane burning may cause deleterious health effects in the exposed population.

Biological effects of air pollution in Sao Paulo and Cubatao

Rats were used as biological indicators of air quality in two heavily polluted Brazilian towns: São Paulo and Cubatão. They were exposed for 6 months to ambient air in areas where the pollution was known to be severe. The following parameters were studied and compared to those of control animals: respiratory mechanics, mucociliary transport, morphometry of respiratory epithelium and distal air spaces, and general morphological alterations. The results showed lesions of the distal and upper airways in rats exposed in Cubatão, whereas the animals from São Paulo showed only alterations of the upper airways but of greater intensity than those observed in the Cubatão group. There are both qualitative and quantitative differences in the pollutants of these places: in São Paulo automobile exhaust gases dominate and in Cubatão the pollution is due mainly to particulates of industrial sources. The correlation of the pathological findings with the pollutants is discussed and it is concluded that biological indicators are useful to monitor air pollutions which reached dangerous levels in São Paulo and Cubatão.

Internet discussion lists as an educational tool.

Sir, Internet discussion lists (DLs) are widely used in organizations for their facility and flexibility1 and have also been used by certain specialists as a forum in which to share experiences2,3. National health services have used DLs to facilitate the day-to-day work of general practitioners4. However, information about the experience of teaching DL techniques seems to be scanty. A key review article5 states that, among other critical factors, the DL must ‘provide a context and rationale for online communication by helping users to establish a shared purpose’, but emphasizes that there is no consensus about methodological approach and measurement techniques to allow comparison studies. Recent developments in applying statistical methods face the challenge of analysing, in quantitative terms, computer-mediated communications6, but descriptive publications are still necessary to clarify different ways to motivate DL participants in diverse contexts7–9. We have used DLs in teaching the first postgraduate course of the Discipline of Telemedicine of the Faculty of Medicine of the University of São Paulo. The course had three teachers and 14 students. The course was conducted in two parts, each lasting one month. The first month was dedicated to lectures (four hours per week) and practical demonstrations (eight hours per week). The objectives were to teach the theoretical, ethical and practical aspects of telemedicine, and to attain the necessary software skills. The requirement to have email at home was an indirect method of ensuring that the participants had a basic familiarity with the Internet and email. During the practical exercises the students were taught how to construct Web pages and how to search for and select medical Web sites, judging their quality by their educational content. In the second month of the course the students established a DL as a project. At the same time, a textual DL was organized as a tool for the development of their projects. These DLs had to be analysed and criticized by every student and improved by the group. Each participant also gained practical knowledge of the advantages and inconveniences of a DL. The students were instructed to use only the list and to avoid any other form of communication about the projects, such as personal discussions, telephone calls and email exchanges, in order to simulate a geographically dispersed group. A conventional DL was used, based on Matt’s WWWBoard, a script written in Perl that can be obtained through Matt’s Script Archive10 and may be modified according to the situation. It is freeware.

A Brazilian model of distance education in physical medicine and rehabilitation based on videoconferencing and Internet learning

We have developed an integrated educational model in rehabilitation mediated by technology. Three teams of professionals worked to implement the interactive model based on videoconferencing, use of the Internet and three-dimensional (3–D) animated models. Two courses were created: amputee rehabilitation and back pain. Each course was divided into four phases: (1) a first videoconference; (2) Internet-based learning; (3) a second videoconference (workshop); (4) an Internet discussion list. The Internet-based learning modules were divided into topics by multiple-choice questions. Multisite videoconferences were used to connect the remote sites. Eleven animated 3–D models were created to help the teaching process. Each course had 11 modules, and each module required up to 2 h to be completed. There were 1 36 participants on the two courses. None of the participants, including the teachers, had had any previous experience with Internet-based learning and videoconferencing. The integrated educational model has great potential in a country the size of Brazil, where there may be difficulties in travel for patients with disabilities and for health-care professionals.

Web Site for Training Nonmedical Health-Care Workers to Identify Potentially Malignant Skin Lesions and for Teledermatology

The development of a Web site to enable nonmedical health professionals to screen skin potentially malignant skin lesions is described. A nurse assistant and a dermatologist tested the Web site. An electronic clinical form was developed to allow a nurse assistant to send case reports and photographs for remote diagnosis by a dermatologist. The nurse assistant photographed the lesions of 92 patients who presented some kind of dermatological condition. The images were then sent for evaluation by the dermatologist followed by in person examination by the same physician. The diagnoses, which resulted from the examination in person and, in some cases, the biopsy results, were compared with the diagnostic impressions of the nurse assistant and with the diagnostic hypothesis of the dermatologist at a distance. The lesions were classified as either malignant or nonmalignant. Kappa statistics showed a high association between the suspected malignity and nonmalignity of the lesions between the dermatologist (p = 6.01 x 10(-9)) and the nurse assistant and between the diagnosis at distance and in person (p < 1.0 x 10(-14)). The Web site allowed a nurse assistant to screen for potentially malignant skin lesions and, thus, proved to be appropriate for a large-scale test.

Acute toxicity of gasoline and ethanol automobile engine exhaust gases.

A comparative inhalation exposure study was performed to investigate the potential health effect of gasoline and ethanol engine exhaust fumes. Wistar rats housed in inhalation chambers were exposed to test atmospheres of various concentrations of carbon monoxide (CO) and gasoline and ethanol exhaust fumes diluted with air. CO level, temperature, relative humidity and flow rate were monitored continually to control the gas concentration and the environment. The dilution method gave a concentration within 1.0% of the target. The LC50s for 3-h exposures were determined for the 3 test atmospheres. The results demonstrated that the acute toxicity, in terms of LC50, of the gasoline-fuelled engine was significantly higher than that of the ethanol-fuelled engine.

Toxicity of prolonged exposure to ethanol and gasoline autoengine exhaust gases

A comparative chronic inhalation exposure study was performed to investigate the potential health effects of gasoline and ethanol engine exhaust fumes. Test atmospheres of gasoline and ethanol exhaust were given to Wistar rats and Balb C mice housed in inhalation chambers for a period of 5 weeks. Gas concentration and physical parameters were continually monitored during the exposure period. Several biological parameters were assessed after the exposure including pulmonary function, mutagenicity, and hematological, biochemical, and morphological examinations. The results demonstrated that the chronic toxicity of the gasoline-fueled engine is significantly higher than that of the ethanol engine.

The efficacy of telemedicine for ophthalmology triage by a general practitioner

Although there are enough ophthalmologists for the Brazilian population, they are not evenly distributed throughout the country. Tele-ophthalmology may therefore be a useful tool. We have examined the feasibility of ophthalmology triage, performed by a general practitioner (GP) with remote support from an ophthalmologist. Forty patients with a variety of external and internal eye disorders were examined by the GP and also reassessed by an ophthalmologist, face to face, and then remotely by another ophthalmologist. There was agreement in 95% of the diagnoses between face-to-face and distant evaluation. The use of a digital camera and slit-lamp allowed greater accuracy of telediagnosis than the use of a digital camera alone. The GP would have referred 36 patients to an ophthalmologist, while both the local and the remote ophthalmologist saw the need for referral in 31 cases, i.e. assessment by tele-ophthalmology resulted in a 14% decrease in referrals. GP triage therefore appears to be feasible after appropriate training.

Computer-assisted rheological evaluation of microsamples of mucus

Dynamic viscoelasticity measurements are required in many studies on biological fluids and they can be performed by determining the corresponding strain when a sinusoidal shear stress is applied to a sample. In several circumstances the amount of fluid that can be obtained for analysis in physiological conditions does not exceed microliters. In this context, the microrheometer technique is a useful approach to determine the dynamic rheological profile of the samples. However, the manual calculation of the desired parameters is tedious and time-consuming. This paper describes a menu-oriented program in order to facilitate its use by non-experts. The comparison between manual and computer-aided calculations demonstrated that the program reduced the time of measurement, and reduced intra- and interobserver variations. The program was developed on an IBM compatible PC in Microsoft C 5.1, and tested in a blind study to check the advantages in terms of time and reproducibility of the system verified by the concordance of two independent observers (interobserver influence) in two different occasions (intraobserver influence).

Environmental epidemiology applied to urban atmospheric pollution: a contribution from the Experimental Air Pollution Laboratory (LPAE).

Systematic investigation on the effects of human exposure to environmental pollution using scientific methodology only began in the 20th century as a consequence of several environmental accidents followed by an unexpected mortality increase above expected mortality and as a result of observational epidemiological and toxicological studies conducted on animals in developed countries. This article reports the experience of the Experimental Air Pollution Laboratory at the School of Medicine, University of São Paulo, concerning the respiratory system and pathophysiological mechanisms involved in responses to exposure to pollution using toxicological and experimental procedures, complemented by observational epidemiological studies conducted in the city of São Paulo. It also describes these epidemiological studies, pointing out that air pollution is harmful to public health, not only among susceptible groups but also in the general population, even when the concentration of pollutants is below the limits set by environmental legislation. The study provides valuable information to support the political and economic decision-making processes aimed at preserving the environment and enhancing quality of life.