Solid waste disposal in urban areas and health--the case of Belo Horizonte, Brazil

The presence of sanitary or controlled landfill in urban areas and its implications for the health of the population that lives in its bordering area has been little investigated. The presence of these deposits, with design or operational problems, can end up providing a likely location for the proliferation of diverse vectors and favouring uncontrolled emissions, which may affect health, both for the people that work and live in these places and those that live nearby. This paper describes a study carried out in the city of Belo Horizonte, Brazil, with the objective of associating the presence of the BR 040 sanitary landfill, located in the urban environment, and the health of the neighbouring population. There were 475 possibilities of occurrences studied, covering 19 different combinations for association between the exposure factor and the groupings of researched diseases (respiratory diseases, diarrhoea and skin diseases). However, of this total only 33 results were shown to be significant in showing the existence of an association. For these results, the variable exposures identified as a risk factor showed an odds ratio ranging between 1.20 and 13.75. Although without an evidenced relationship, respiratory diseases appeared as a relevant outcome in the study, as they were present in 23 of the 33 studied combinations in which the results were significant.

Environmental sanitation conditions and health impact: a case-control study

This epidemiological investigation examines the impact of several environmental sanitation conditions and hygiene practices on diarrhea occurrence among children under five years of age living in an urban area. The case-control design was employed; 997 cases and 999 controls were included in the investigation. Cases were defined as children with diarrhea and controls were randomly selected among children under five years of age. After logistic regression adjustment, the following variables were found to be significantly associated with diarrhea: washing and purifying fruit and vegetables; presence of wastewater in the street; refuse storage, collection and disposal; domestic water reservoir conditions; feces disposal from swaddles; presence of vectors in the house and flooding in the lot. The estimates of the relative risks reached values up to 2.87. The present study revealed the feasibility of developing and implementing an adequate model to establish intervention priorities in the field of environmental sanitation.

Conductivities of three-layer live human skull

Electrical conductivities of compact, spongiosum, and bulk layers of the live human skull were determined at varying frequencies and electric fields at room temperature using the four-electrode method. Current, at higher densities that occur in human cranium, was applied and withdrawn over the top and bottom surfaces of each sample and potential drop across different layers was measured. We used a model that considers variations in skull thicknesses to determine the conductivity of the tri-layer skull and its individual anatomical structures. The results indicate that the conductivities of the spongiform (16.2-41.1 milliS/m), the top compact (5.4-7.2 milliS/m) and lower compact (2.8-10.2 milliS/m) layers of the skull have significantly different and inhomogeneous conductivities. The conductivities of the skull layers are frequency dependent in the 10-90 Hz region and are non-ohmic in the 0.45-2.07 A/m2 region. These current densities are much higher than those occurring in human brain.

[Outbreak of hemolytic reactions associated with chlorine and chloramine residuals in hemodialysis water]

OBJECTIVE

To investigate the process of water contamination and to assess the subsequent outbreak in the hemodialysis center.

METHODS

In September 2000, sixteen patients undergoing chronic hemodialysis at a dialysis center in Minas Gerais, Brazil, experienced hemolytic reactions compatible with toxic symptoms due to chlorine and chloramine water contamination. Chlorine and chloramine concentrations in samples obtained from various sites of the dialysis center's water treatment and distribution system were measured. Case-patients were identified by reviewing medical records and nursing notes for all dialysis sessions carried out during the study period. Interviews with technicians, nursing and medical staff members were conducted.

RESULTS

Reaction rate was significantly higher (p<0.028) during the outbreak period (September 25 to 27, 2000) than the pre-outbreak period (September 18 to 20, 2000). All patients with toxic symptoms had been under dialysis with water treated by reverse osmosis equipment and had used dialysers manually reprocessed. Chlorine and chloramine residuals concentrations found in the dialysis water as well as in the dialysers were at levels higher than regulations, </=0.5 mg/L for chlorine and </= 0.1 mg/L for chloramine. Individuals exposed to high chlorine and chloramine concentrations presented a relative risk of 2.58 (1.0-6.28) of having hemolytic reactions.

CONCLUSION

There is a need to observe surveillance procedures to secure that the maximum allowable concentrations of regulated substances in the water used in the hemodialysis process are not exceeded.

Lower extremity microsurgical reconstruction

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Understand the indications for the use of free-tissue transfer in lower extremity reconstruction. 2. Understand modalities to enhance the healing and care of soft tissue and bone before free-tissue transfer. 3. Understand the lower extremity reconstructive ladder and the place of free-tissue transfer on the ladder. 4. Understand the specific principles of leg, foot, and ankle reconstruction. 5. Understand the factors that influence the decision to perform an immediate versus a delayed reconstruction. Free-tissue transfer using microsurgical techniques is now routine for the salvage of traumatized lower extremities. Indications for microvascular tissue transplantation for lower extremity reconstruction include high-energy injuries, most middle and distal-third tibial wounds, radiation wounds, osteomyelitis, nonunions, and tumor reconstruction. The authors discuss the techniques and indications for lower extremity reconstruction.

Tumour necrosis factor mediates bacterial translocation after haemorrhagic shock and endotoxaemia

OBJECTIVE

To assess the extent of bacterial translocation after haemorrhagic shock and reperfusion, and the involvement of tumour necrosis factor (TNF) in its mediation.

DESIGN

Controlled, randomised prospective experiment.

SUBJECTS

87 rats in 7 groups.

INTERVENTIONS

Haemorrhagic shock was induced in rats for 1 hour. Endotoxaemia was induced in a second group by the injection of lipopolysaccharide. A third group was injected with exogenous TNF. Some of the animals were further treated with anti-TNF.

MEASUREMENTS

After 24 hours, bacterial translocation in blood and in several remote organs, and serum TNF concentrations were measured.

RESULTS

High bacterial counts were found in all remote organs of rats with haemorrhagic shock or endotoxaemia. Their serum TNF concentrations were significantly higher than in the corresponding sham-operated controls. Anti-TNF significantly reduced the extent of bacterial translocation. Rats, the only treatment of which was exogenous TNF, developed substantial bacterial translocation.

CONCLUSION

Bacterial translocation is associated with increased serum TNF, and can be minimised by anti-TNF. This, and the triggering of translocation in unprovoked animals by TNF alone, suggest that TNF may be the stimulator, and not the consequence, of bacterial translocation.

Laser Doppler flowmeter monitoring of free-tissue transfers: blood flow in normal and complicated cases

In this article, laser Doppler flowmeter (LDF) monitoring of blood flow in 94 free flaps is summarized. Seventy-six patients had uneventful postoperative courses, and 18 patients developed postoperative complications, with a salvage rate of 88 percent. Except for one case, the flowmeter identified developing complications before clear clinical indices appeared, and in two cases it was the only indication of vascular compromise of the flap. On the basis of the data obtained, the ranges of absolute flow values in different types of uncomplicated flaps are reported, along with their temporal pattern of flow. Decrease inflow pattern may be an early indicator of a developing perfusion disturbance. On the basis of LDF readings, the following classifications of free-flap blood flow are suggested. (1) If the flow is within or slightly above the established range, then normal diligence in observation is justified. If the flow is well above the normal range, artifacts that could falsely elevate readings should be investigated. (2) If the flow is somewhat below the established range, then a modest increase in observation is warranted (alert level 1). (3) If the relative flow falls to 50 percent of the initial flow of that flap and remains at that level for 30 minutes or longer, then more aggressive flap observation is indicated (alert level 2). (4) If the flow is below 0.4 LDF units for 30 minutes, then aggressive clinical observation should be performed (alert level 3, or "red alert") and exploration should be strongly considered. Falsely elevated measurements can be caused by vibration, motion of the probe or tissue, or location of the probe over a macroscopic blood vessel. False low readings are quite rare but can result from partial probe detachment from the flap or coagulum accumulating on the probe. Once artifacts are ruled out, LDF readings have a high level of credibility and, in the authors' experience, significantly improve salvage rates.

Conductivities of three-layer human skull

In this study, electrical conductivities of compact, spongiosum, and bulk layers of cadaver skull were determined at varying electric fields at room temperature. Current was applied and withdrawn over the top and bottom surfaces of each sample and potential drop across different layers was measured using the four-electrode method. We developed a model, which considers of variations in skull thicknesses, to determine the conductivity of the tri-layer skull and its individual anatomical structures. The results indicate that the spongiform and the two compact layers of the skull have significantly different and inhomogeneous conductivities ranging from 0.76 +/- .14 to 11.5 +/- 1.8 milliS/m.

In vivo electroporation of plasmids encoding GM-CSF or interleukin-2 into existing B16 melanomas combined with electrochemotherapy induces long-term antitumour immunity

When cancer cells, including melanoma cells, are genetically altered to secrete cytokines, irradiated and injected into subjects, long-term antitumour immunity is induced. Optimally, existing melanomas induced to produce cytokines in vivo could stimulate this same immune response. Although in vivo electroporation enhances plasmid expression, electroporation of plasmids encoding granulocyte-monocyte colony stimulating factor (GM-CSF) and interleukin-2 (IL2) into B16 mouse melanomas did not significantly alter tumour growth at the concentration tested. Electrochemotherapy, which causes short-term, complete regressions of treated tumour but no resistance to challenge, was combined with plasmid delivery. The combination treatment resulted in the induction of long-term immunity to recurrence and resistance to challenge in up to 25% of mice.

Electrically mediated plasmid DNA delivery to hepatocellular carcinomas in vivo

Gene therapy by direct delivery of plasmid DNA has several advantages over viral gene transfer, but plasmid delivery is less efficient. In vivo electroporation has been used to enhance delivery of chemotherapeutic agents to tumors in both animal and human studies. Recently, this delivery technique has been extended to large molecules such as plasmid DNA. Here, the successful delivery of plasmids encoding reporter genes to rat hepatocellular carcinomas by in vivo electroporation is demonstrated.

Development of an instrument to assess nutritional risk factors for children infected with human immunodeficiency virus

OBJECTIVE

To produce a simple and effective instrument to evaluate and monitor the nutritional risk of children infected with the human immunodeficiency virus (HIV).

DESIGN

The test instrument was developed in consultation with 5 physicians, 5 nutritionists, and 5 social workers with expertise in caring for HIV-infected children. Patient information was collected through medical record review for 19 sociodemographic, 10 anthropometric, 4 biochemical, 6 dietary intake, and 19 medical factors. As a part of routine nutrition care, anthropometric data were obtained and the caregiver was asked to complete a 3-day diet record. Also recorded were the most recent CD4+ T-cell numbers and serum HIV p24 antigen and plasma HIV RNA levels.

SUBJECTS/SETTING

Thirty-nine HIV-infected children were selected using quota sampling; that is, subjects were stratified by clinical class as defined by the Centers for Disease Control and Prevention.

STATISTICAL ANALYSIS

The severity or degree of potential nutritional risk in each section (anthropometric, biochemical, dietary intake, and medical data) was graded (0 to 4, 0 = low risk) and summed. Reliability of internal consistency was determined through covariance matrixes. Validity was determined through Pearson product moment correlation coefficients to measure convergent and divergent validity; predictive validity was determined using analysis of variance. Correlation for validity was compared to 6 selected dependent variables: weight for height, weight growth velocity, lean body mass, serum albumin level, CD4+ T-cell numbers, and quantitative plasma HIV RNA levels.

RESULTS

Of the 38 factors that were analyzed for reliability, 11 fell in the strongly reliable range: height for age, weight for age, clinical class, somatic protein stores, mid-arm circumference, weight for height, serum albumin, immunologic status, body mass index, energy intake, and opportunistic infection.

CONCLUSIONS

Anthropometric, dietary intake, and medical data were reliable indicators of nutritional risk. The entire instrument was reliable after 8 of the weakest items were removed. The instrument was found to be valid and a good predictor of nutritional risk in HIV-infected children.

Tc-99m sestamibi scintimammography in the mammographically dense breast

PURPOSE

The mammographically dense breast or the "difficult-to-interpret mammogram" poses significant clinical and diagnostic imaging concerns. From our experience using Tc-99m sestamibi mammography in more than 650 patients, we share our experience in a pictorial manner and include suggested indications and limitations of this exciting new technique. Examples of Tc-99m sestamibi imaging in six patients with mammographically dense breasts are presented.

MATERIALS AND METHODS

All patient examinations were ordered clinically for various indications. Comparison radiographic mammography and, when available, confirmatory pathologic analysis were also done. The examples were chosen from our experience with more than 650 patients at two university hospitals and one outpatient imaging center.

RESULTS

Of the six examples presented, four had cancer, one had fibrosis after chemotherapy for ductal cell carcinoma, and one had no evidence of cancer. Tc-99m sestamibi imaging showed no increased uptake in the one patient with no tumor and various degrees of uptake in the other five patients.

CONCLUSIONS

Six examples from our clinical experience show the usefulness of Tc-99m sestamibi imaging in patients with mammographically dense breasts. The ability to identify a malignancy or its absence supports the continued use of this procedure in these patients.

Evaluation of the effects of oxandrolone on malnourished HIV-positive pediatric patients

OBJECTIVE

To determine the safety and efficacy of anabolic therapy to prevent or reverse wasting and malnutrition in human immunodeficiency virus (HIV)-infected pediatric patients. The anabolic steroid, oxandrolone, was evaluated because of its safe and effective use in other pediatric conditions.

METHODS

Nine HIV-positive children who were malnourished or at risk for malnutrition (4 females, 5 males; 4-14 years of age) took oxandrolone for 3 months (.1 mg/kg/day orally). Quantitative HIV ribonucleic acid polymerase chain reaction and CD4(+) T-cell levels, complete blood cell count (CBC) and chemistry profile, endocrinologic studies, resting energy expenditure, respiratory quotient, nutritional measures, body composition assessment with quantitative computed tomography, and skinfold body composition measurements were determined before treatment, during treatment (3 months), and for 3 months after treatment. Statistical analyses were completed using the Friedman two-way analysis of variance and Spearman correlation tests.

RESULTS

No adverse clinical or laboratory events or changes in Tanner staging or virilization occurred. Quantitative HIV ribonucleic acid polymerase chain reaction and CD4(+) T-cell levels did not change significantly. Insulin-like growth factor 1 increased, suggesting an anabolic effect of treatment. The rate of weight gain increased during treatment and was maintained after treatment. Linear growth continued and was maintained throughout treatment, whereas bone age did not increase significantly. Anthropometric assessments indicated an increase in muscle mass and a decrease in fat while patients were on treatment, and a mild decrease of muscle and increased fat posttreatment. Likewise, computed tomography scan results demonstrated similar changes in muscle mass. Resting energy expenditure and respiratory quotient remained stable throughout treatment and follow-up. No significant changes were seen in the quality of life questionnaire.

CONCLUSIONS

Treatment with oxandrolone for 3 months in HIV-infected children was well-tolerated, safe, and associated with markers of anabolism. The latter effect was maintained partially for 3 months after discontinuation of a 3-month course of therapy. Additional studies are needed to assess the potential benefits and risks of a longer course of therapy or a higher dose of oxandrolone in HIV-infected children.

Bladder tone in patients in post-traumatic vegetative state

The aim of the present study was to examine the bladder tone in vegetative patients using urodynamic tests. The study population consisted of 17 patients, 13 men and four women, in a post-traumatic vegetative state under treatment at the Loewenstein Rehabilitation Centre. Time since injury ranged from 1 to 6 months. Cystometry results indicated that 100% of the patients had neurogenic bladder, hypertonic type, two (12%) with mild spasticity and 15 (88%) with severe spasticity. None showed detrusor-sphincter dyssynergia or unstable bladder. Based on these unequivocal findings, it is suggested that all patients in trauma-induced vegetative state be treated prophylactically from the 2nd week with anticholinergic agents.

[Drug-related hyperkalemia resulted from spironolactone and angiotensin converting enzyme inhibitors therapy]

A case of drug-related hyperkaliemia linked to treatment with angiotensin converting enzyme inhibitors and spironolactone simultaneously. The paper presents the case of drug-related hiperkaliemia induced by captopril and spironolactone combined treatment in a patient with early stage of renal failure.

[Association between household solid waste disposal and health, Belo Horizonte (MG), Brasil]

There are few published studies about the effects of inadequate solid waste collection on the health of the population exposed to this situation. The objective of the present work was to describe this association in a sample of children under 5 years of age living in seven low-income neighborhoods and favelas in the city of Belo Horizonte, state of Minas Gerais, Brazil. We defined as "exposed" those children whose families were not served by waste collection; "not-exposed" were children who lived in areas with waste collection. The study employed data collected in 1994 and organized as a database by the municipal department of health. We employed a cross-sectional design, in which a "case" was defined as a child whose outpatient clinic record indicated a diagnosis of diarrheal, parasitic, or dermatological disease. Other diagnoses for the same age group composed the control group. Our epidemiological study revealed an association between the absence of domestic solid waste collection and public health. Our results suggest that the children exposed to the absence of solid waste collection have a 40% higher odds (OR = 1.40) of presenting diarrheal, parasitic, and dermatological diseases than not-exposed children. In addition, the calculation of attributable risk revealed that the presence of waste collection could prevent (based on the 1995 situation) 512 cases in the neighborhoods studied and (based on the 1994 conditions) 2316 cases among children in the entire city of Belo Horizonte.

Environmental determinants of infectious and parasitic diseases

A review of the role of the environment as a determinant of infectious and parasitic diseases is presented. Historical considerations and the several environmental classifications of diseases are introduced. In a broader perspective the subject is analyzed in view of the emergence of the environmental health area, with its new paradigms. A review of epidemiological studies about environmental sanitation conditions and measures is presented, analyzing the conclusions derived from 256 studies. Finally, an epidemiological study carried out in Betim, Minas Gerais is briefly described, in order to illustrate the potentiality of this kind of study. Setting priorities of interventions regarding diarrhea control was the aim of this investigation. Conclusion about the role of this approach to optimize preventive measures for the control of infectious and parasitic diseases, of sound importance to the reality of the developing world, is stated.

Relação entre saúde e saneamento na perspectiva do desenvolvimento

Discute-se a relação entre saúde e saneamento, situando-a no contexto do processo de desenvolvimento social. É defendida inicialmente a inserção dessa relação no atual enfoque saúde e ambiente, reconhecendo que esta nova área não elimina a pertinência da abordagem saúde-saneamento, na verdade sua precursora. Apresenta-se a conceituação de saneamento e sua atual situação no país, além dos marcos conceituais da relação saúde-saneamento. Indicadores de desenvolvimento dos países, enfatizando os brasileiros, são confrontados com indicadores sanitários, mostrando-se que, para o grau de desenvolvimento econômico e a cobertura por serviços de saneamento no Brasil, melhor desempenho dos indicadores de saúde seria esperado. Avaliam-se as assertivas que podem ser extraídas dos estudos epidemiológicos desenvolvidos na área de saneamento e, por fim, discutem-se as perspectivas que se apresentam no campo da relação saúde-saneamento.

Heterotopic abdominal pregnancy following in-vitro fertilization/embryo transfer presenting as massive lower gastrointestinal bleeding

We present a case that, as far as we know, is the first report of lower gastrointestinal haemorrhage as a complication of heterotopic pregnancy induced by artificial reproductive technology. The heterotopic abdominal pregnancy caused erosion of the intestinal wall and massive rectal bleeding, 8 weeks after in-vitro fertilization/embryo transfer. The source of the bleeding could not be identified despite comprehensive investigation including gastroscopy, ultrasonography, sigmoidoscopy, 99Tc (technetium) scanning and angiography. Tagged-erythrocyte isotope scanning revealed an abnormal concentration in the left lower quadrant, compatible with active bleeding in the area of the terminal ileum. Laparotomy disclosed a heterotopic abdominal pregnancy, causing erosion of the intestinal wall at this site. As assisted reproductive technologies become more and more common this rare complication of intestinal erosion should be kept in mind in case of lower gastrointestinal bleeding.

Evaluation of boundary element methods for the EEG forward problem: effect of linear interpolation

We implement the approach for solving the boundary integral equation for the electroencephalography (EEG) forward problem proposed by de Munck [1], in which the electric potential varies linearly across each plane triangle of the mesh. Previous solutions have assumed the potential is constant across an element. We calculate the electric potential and systematically investigate the effect of different mesh choices and dipole locations by using a three concentric sphere head model for which there is an analytic solution. Implementing the linear interpolation approximation results in errors that are approximately half those of the same mesh when the potential is assumed to be constant, and provides a reliable method for solving the problem.

Rate of weight gain of inpatients with anorexia nervosa under two behavioral contracts

OBJECTIVE

To ascertain the rate of weight gain of inpatients with anorexia nervosa under two behavioral contracts, differing in criterion weight gain required to earn increasing privileges.

DESIGN

Follow-up comparison of cohorts receiving different interventions.

SETTING

Eating disorders service, operating on a general adolescent medicine unit.

PATIENTS

Patients admitted consecutively who met the following criteria: (1) weight at least 15% less than that expected for age, sex, and height; (2) female gender; (3) absence of chronic medical illness; (4) hospital stay of at least 28 days. Twenty-two patients meeting these criteria were treated between July 1987 and October 1988, when contract 1 was in effect. This cohort of patients was compared with a group of 31 patients, also meeting the these criteria, who were treated between November 1988 and December 1991, when contract 2 was in effect.

INTERVENTIONS

The behavioral contract, signed by the patient on admission, specifies the minimum 4-day weight gain necessary to earn increasing ward privileges, such as use of phone, frequency of visits, etc. Contracts 1 and 2 differed only in the 4-day weight gain criterion: 0.8 lb (0.36 kg) and 1.2 lb (0.55 kg), respectively.

RESULTS

The results of analysis of covariance, with admission weight as the covariate, revealed a significant interaction between contract and day, such that patients receiving contract 2 gained weight more rapidly (0.36 lb/d) than those receiving contract 1 (0.20 lb/d). There was no confounding difference between groups in the use of psychotropic medication, and no complications of refeeding in either group.

CONCLUSION

Increasing the 4-day criterion weight gain from 0.8 to 1.2 lb in a behavioral contracting intervention was associated with a significant increase in the rate of weight gain, without an accompanying increase in complications of refeeding. This result simultaneously: (a) provides support for the efficacy of behavioral contracting and (b) reveals malleability in the rate of gain based on the targeted gain specified in the contract.