Showing papers by "Rio de Janeiro State University published in 1999"

Divergent roles for thyroid hormone receptor β isoforms in the endocrine axis and auditory system

Abstract: Thyroid hormone receptors (TRs) modulate various physiological functions in many organ systems. The TRα and TRβ isoforms are products of 2 distinct genes, and the β1 and β2 isoforms are splice variants of the same gene. Whereas TRα1 and TRβ1 are widely expressed, expression of the TRβ2 isoform is mainly limited to the pituitary, triiodothyronine-responsive TRH neurons, the developing inner ear, and the retina. Mice with targeted disruption of the entire TRβ locus (TRβ-null) exhibit elevated thyroid hormone levels as a result of abnormal central regulation of thyrotropin, and also develop profound hearing loss. To clarify the contribution of the TRβ2 isoform to the function of the endocrine and auditory systems in vivo, we have generated mice with targeted disruption of the TRβ2 isoform. TRβ2-null mice have preserved expression of the TRα and TRβ1 isoforms. They develop a similar degree of central resistance to thyroid hormone as TRβ-null mice, indicating the important role of TRβ2 in the regulation of the hypothalamic-pituitary-thyroid axis. Growth hormone gene expression is marginally reduced. In contrast, TRβ2-null mice exhibit no evidence of hearing impairment, indicating that TRβ1 and TRβ2 subserve divergent roles in the regulation of auditory function.

Short-term associations between outdoor air pollution and visits to accident and emergency departments in London for respiratory complaints.

Abstract: Many epidemiological studies have shown positive short-term associations between health and current levels of outdoor air pollution. The aim of this study was to investigate the association between air pollution and the number of visits to accident and emergency (A&E) departments in London for respiratory complaints. A&E visits include the less severe cases of acute respiratory disease and are unrestricted by bed availability. Daily counts of visits to 12 London A&E departments for asthma, other respiratory complaints, and both combined for a number of age groups were constructed from manual registers of visits for the period 1992-1994. A Poisson regression allowing for seasonal patterns, meteorological conditions and influenza epidemics was used to assess the associations between the number of visits and six pollutants: nitrogen dioxide, ozone, sulphur dioxide, carbon monoxide, and particles measured as black smoke (BS) and particles with a median aerodynamic diameter of <10 microm (PM10). After making an allowance for the multiplicity of tests, there remained strong associations between visits for all respiratory complaints and increases in SO2: a 2.8% (95% confidence interval (CI) 0.7-4.9) increase in the number of visits for a 18 microg x (-3) increase (10th-90th percentile range) and a 3.0% (95% CI 0.8-5.2) increase for a 31 microg x m(-3) increase in PM10. There were also significant associations between visits for asthma and SO2, NO2 and PM10. No significant associations between O3 and any of the respiratory complaints investigated were found. Because of the strong correlation between pollutants, it was difficult to identify a single pollutant responsible for the associations found in the analyses. This study suggests that the levels of air pollution currently experienced in London are linked to short-term increases in the number of people visiting accident and emergency departments with respiratory complaints.

Short-term associations between emergency hospital admissions for respiratory and cardiovascular disease and outdoor air pollution in London

Abstract: There are concerns about the possible short-term effects of outdoor air pollution on health in the United Kingdom. In a study conducted during the time period between 1987 and 1992, investigators determined that ozone had small, but significant effects on emergency respiratory admissions. In the current study, the authors investigated associations between emergency admissions and outdoor air pollution for the time period from 1992 to 1994, inclusive, and compared the results with those obtained in the earlier study. The authors also examined particulate matter less than 10 μmlm in diameter (PM10) and carbon monoxide in the current study. Appropriate confounding factors, such as seasonal patterns, temperature, and humidity, were controlled for, and the authors used Poisson regression to estimate the association between daily emergency admissions for respiratory and cardiovascular diseases and ozone, nitrogen dioxide, sulfur dioxide, carbon monoxide, particles measured as Black Smoke, and PM10. Sig...

The prevalence and impact of dental pain in 8-year-old school children in Harrow, England.

Abstract: Objective To assess the prevalence, severity and impact of dental pain. Design Cross-sectional survey. Setting Schools in the London Borough of Harrow, England, in the summer term of 1995. Subjects and methods The base population were all 2,300 8-year-old school children in Harrow. A cluster sampling of schools based on quotas from all postcode areas in Harrow was used. Data were collected through interviews with the children. Main outcome measures Prevalence of previous toothache; prevalence of toothache in the previous 4 weeks; prevalence of toothache in the previous 4 weeks which resulted in a visit to the dentist, in stopping playing, eating, sleeping, going to school and taking painkillers. Results Of the 664 sample of children in the participating schools, 589 were interviewed (88.7%). The frequency of previous toothache was 47.5% (95% CI, 44–52) and dental pain caused crying in 17.7% (95% CI, 15–21) of children. 7.6% (95% CI, 5–11) of children had pain in the previous 4 weeks (45 children). Among these 45 children, this recent pain resulted in a visit to the dentist in 41.9% (19 children, ie 3.2% of all children), in stopping playing in 26.7% (12 children, ie 2.0% of all children), eating in 73.3% (33 children, ie 5.6% of all children), sleeping in 31.1% (14 children, ie 2.4% of all children) and in going to school in 11.1% (5 children, ie 0.8% of all children). Conclusion Toothache in children is a sizeable problem in Harrow and had substantial consequences for children and their guardians. Freedom from disabling dental pain/discomfort is an outcome indicator of oral health and could be used as an explicit goal by dental systems. It is important to note however, that the present study did not assess the extent to which the dental pain was associated with avoidable dental problems as opposed to normal physiological processes. It is important that future work try and separate the prevalence of dental pain caused by physiological from avoidable pathological factors. In addition, future work is needed to assess how effectively and efficiently dental services are responding to people suffering with dental pain.

A first principles warm inflation model that solves the cosmological horizon and flatness problems

Abstract: A quantum field theory warm inflation model is presented that solves the horizon and flatness problems. The model obtains, from the elementary dynamics of particle physics, cosmological scale factor trajectories that begin in a radiation dominated regime, enter an inflationary regime, and then smoothly exit back into a radiation dominated regime, with non-negligible radiation throughout the evolution. {copyright} {ital 1999} {ital The American Physical Society}

[Anthropometric profile of the elderly Brazilian population: results of the National Health and Nutrition Survey, 1989].

Abstract: This paper presents the nutritional status of the elderly Brazilian population (60 years and older) based on a probabilistic sample survey in 1989. Nutritional assessment used the BMI (kg/m2), with cut-off points recommended by the WHO (1995). Socio-demographic variables included age, gender, region and place of residence in the country (urban/rural area), income, education, and housing conditions. Prevalence rates for thinness (BMI < 18.5) and overweight (BMI ( 25) were 7.8% and 30.4% in men and 8.4% and 50.2% in women, higher than in the young adult population. Thinness was more frequent in older women, in rural areas from the Midwest/Northeast regions (women) and Southeast/Midwest (men), in groups with lower income, less schooling, and worse housing conditions. Overweight was more frequent in women from urban areas in the South and Southeast and groups with higher income, more schooling, and better housing conditions. The results indicate problematic nutritional status in the Brazilian elderly, particularly women.

Effects of Climate and Food Availability on Four Rodent Species in Southeastern Brazil

Abstract: Seasonal reproduction of small mammals in the tropics usually is related to annual cycles of rainfall. We examined effects of weather and food availability on reproduction and population ecology of Nectomys squamipes, Oryzomys intermedius, Akodon cursor and Trinomys iheringi . Each species was studied monthly from February 1993 to January 1995 using mark-recapture methods at Ilha do Cardoso, Sao Paulo State, Brazil. Average capture rate for each month was used as an index of population size, and survival rate was estimated by the Jolly-Seber method. Direct effects of food availability and rainfall were related to female reproductive activity and survival rate. Path analyses were used to describe quantitatively the hypothesized causal relations among the variables. N. squamipes reproduced seasonally, and O. intermedius, T. iheringi , and A. cursor reproduced all year with peaks during the rainy season. Species responded differently to the environmental factors; however, food availability seems to be the main factor determining reproduction. Abundance of rains appears to diminish survival rate of O. intermedius . Survival rate of N. squamipes increases with increases in fruit availability.

Mechanical Forces Induce Scar Remodeling : Study in Non-Pressure-Treated versus Pressure-Treated Hypertrophic Scars

Abstract: Reparative process of second and third degree burns usually results in hypertrophic scar formation that can be treated by pressure. Although this method is efficient, its mechanisms of action are not known. In this work, we have studied the histological organization of hypertrophic scars submitted to pressure. Skin biopsies were performed 2 to 7 months after the onset of treatment in two adjacent regions of the scar, non-pressure- or pressure-treated and analyzed by immunohistochemistry and transmission electron microscopy for extracellular matrix organization and cellular morphology. In non-pressure-treated regions, fibrillin deposits did not present the classical candelabra-like pattern under epidermis and were reduced in dermis; in pressure-treated regions the amount was increased compared to non-pressure-treated regions but the organization was still disturbed. In non-pressure-treated regions, elastin was present in patch deposits; in pressure-treated regions elastin formed fibers, smaller than in normal dermis. Tenascin was present in the whole dermis in non-pressure-treated regions, whereas in pressure-treated regions it was observed only under epidermis and around vessels, as in normal skin. α-Smooth muscle actin-expressing myofibroblasts were absent in normal skin, present in large amounts in non-pressure-treated regions, and almost absent in pressure-treated regions. The disturbed ultrastructural organization of dermal-epidermal junction observed in non-pressure-treated regions disappeared after pressure therapy; typical features of apoptosis in fibroblastic cells and morphological aspects of collagen degradation were observed in pressure-treated regions. Our results show that, in hypertrophic scars, pressure therapy restores in part the extracellular matrix organization observed in normal scar and induces the disappearance of α-smooth muscle actin-expressing myofibroblasts, probably by apoptosis. We suggest that the pressure acts by accelerating the remission phase of the postburn reparative process.

Increased Interleukin-1β Concentration in Gingival Crevicular Fluid as a Characteristic of Periodontitis.

Abstract: Background: The levels of interleukin-1β (IL-1β) have been reported to be higher in sites with periodontitis than in healthy controls. This may be the result of a more severe inflammation and/or constitutional differences in IL-1β production. Our aim was to test the hypothesis that the level of IL-1β in gingival crevicular fluid (GCF) is a characteristic trait of periodontitis, regardless of the degree of tissue destruction. As a secondary aim, we investigated the correlation between IL-1β and neutrophil elastase. An untreated population was used. Methods: GCF samples from inflamed sites in 13 patients with gingivitis (GG), and from inflamed sites with shallow (GP) and deep (PP) pockets in 18 patients with periodontitis were collected. Interleukin-1β, elastase-α-1-antitrypsin complex (E-A1AT), α-1- antitrypsin (A1AT), and α-2-macroglobulin (A2MG) were measured with ELISA. Elastase activity was measured with a specific substrate. Results: The concentration of IL-1β was significantly higher in PP than in GG...

O Projeto Unesco e a agenda das ciências sociais no Brasil dos anos 40 e 50

Abstract: The article describes how the series of studies into race relations in Brazil was structured in the 1950s, under the auspices of Unesco. By focusing on the actions of certain social actors and their respective views regarding this intellectual undertaking, it is possible to establish the links between the demands of the international agency and the range of questions that were being raised by Brazilian social scientists. These questions composed an agenda defined by Arthur Ramos in the late 1940s, which challenged the Brazilian university-based intelligentsia to associate its professional enhancement with increased research directed at what Ramos considered the singularity of Brazil, its condition of a "laboratory of civilization". For Ramos, the topic of race relations had a special status in the perception and analysis of the difficulties associated with the transition from tradition to modernity, of a scenario filled with remarkable social and racial inequalities, of regional diversity and of the construction of a definitive national identity.

[Waist:hips girth ratio as a predictor of arterial hypertension].

Abstract: Este trabalho tem como objetivo definir pontos de corte para a razao cintura/quadril (RCQ), usando como desenlace a hipertensao arterial. Os dados obtidos referem-se a 3.282 individuos com idade acima de vinte anos, examinados numa pesquisa realizada no Municipio do Rio de Janeiro, em 1995-1996, utilizando amostra em dois estagios. Inicialmente, foram sorteados sessenta setores censitarios; posteriormente, 34 domicilios foram selecionados sistematicamente em cada setor. Altura, peso, perimetros da cintura e do quadril e pressao arterial foram medidos nos domicilios. Foram considerados hipertensos os que apresentavam pressao sistolica 140 mmHg ou pressao diastolica 90 mmHg, ou, ainda, os que faziam uso de medicamento para reduzir a pressao arterial. Foram calculadas a sensibilidade e a especificidade de diferentes pontos de corte para a RCQ na predicao de hipertensao arterial segundo sexo, idade e presenca de sobrepeso, classificado segundo proposta da Organizacao Mundial da Saude. Os melhores pontos de corte para a RCQ foram 0,95 para homens e 0,80 para mulheres. Comparada com a razao cintura/altura e com o perimetro da cintura, a RCQ apresentou maior capacidade preditiva de hipertensao e menor correlacao com o indice de massa corporal.

Pseudomonas aeruginosa Internalization by Human Epithelial Respiratory Cells Depends on Cell Differentiation, Polarity, and Junctional Complex Integrity

Abstract: Internalization of Pseudomonas aeruginosa by epithelial respiratory cell lines has been suggested to be dependent on the cystic fibrosis transmembrane conductance regulator (CFTR) protein. Because we have observed intracellular (IC) P. aeruginosa only in cells that do not express apical CFTR, we addressed the question of whether bacterial internalization by epithelial cells depends on the degree of cell differentiation and polarity. Internalization of piliated P. aeruginosa PAO-1 and PAK by human epithelial respiratory cells in primary culture and by the 16 human bronchial epithelial 14o- cell line cultured either on thick collagen gels or on thin collagen films was evaluated by the gentamicin exclusion assay. Cells cultured on thick gels were differentiated, polarized, and tight. They exhibited CFTR at their apical membranes, expressed beta1 integrins at their basal membranes, excluded lanthanum nitrate, and uniformly expressed ZO-1 protein. In contrast, in cells cultured on thin films, CFTR was present mainly in the cytoplasm, whereas beta1 integrins were detected at apical membranes. Most cells cultured on thin films did not exclude lanthanum nitrate and rarely expressed ZO-1 protein. Cells grown on thick and thin collagen substrates differed markedly in bacterial internalization: no IC bacteria could be detected in cells cultured on gels, whereas high IC bacterial concentrations were isolated from cells cultured on thin films. Treatment of cells cultured on thin films with ethylenediaminetetraacetic acid, to disrupt intercellular junctions further, significantly enhanced P. aeruginosa internalization. Our results suggest that P. aeruginosa internalization by epithelial respiratory cells does not depend on CFTR protein expression at the epithelial cell surface but rather on cell polarity and junctional complex integrity.

Fibronectin and alpha5beta1 integrin mediate binding of Pseudomonas aeruginosa to repairing airway epithelium

Abstract: Initial infection of the airway by Pseudomonas aeruginosa may occur through a variety of bacterial strategies including binding to epithelial receptors present at the surface of the respiratory epithelium. In order to characterize the adherence sites for P. aeruginosa in damaged and repairing bronchial tissue, an ex vivo model of airway epithelial injury and repair was developed using primary cell cultures of nasal cells from 14 subjects with polyposis. P. aeruginosa strongly adhered to flattened dedifferentiated (FD) bronchial and nasal cytokeratin 13-positive epithelial cells in the process of migration for repair. In in vitro experiments, competitive binding inhibition assays demonstrated that alpha5beta1 integrins and cellular fibronectin, in particular the RGD sequence, are receptors involved in P. aeruginosa adherence to FD nasal epithelial cells. Fluorescent cell sorting analysis and immunofluorescence techniques revealed that the alpha5beta1 integrins are overexpressed and apically exposed in FD nasal epithelial cells. One 50 kDa outer membrane protein was identified in piliated and nonpiliated strains of P. aeruginosa that was involved in binding to cellular fibronectin and alpha5beta1 epithelial integrins. These results demonstrate that Pseudomonas aeruginosa adherence is related to the dedifferentiation of airway epithelium during the repair process which unmasks and upregulates the alpha5beta1 integrin expression and induces active synthesis of cellular fibronectin. These epithelial receptors are then used by a Pseudomonas aeruginosa 50 kDa outer membrane protein as sites of bacterial adherence.

The modified method of characteristics with adjusted advection

Abstract: The MMOC procedure for approximating the solutions of transport-dominated diffusion problems does not automatically preserve integral conservation laws, leading to (mass) balance errors in many kinds of flow problems. The variant, called the MMOCAA, discussed herein preserves the conservation law at a minor additional computational cost. It is shown that its solution, in either Galerkin or finite difference form, converges at the same rates as were proved earlier by Dougl as and Russell for the standard MMOC procedure.

Constipation in school-aged children at public schools in Rio de Janeiro, Brazil

Abstract: Background:Constipation in childhood is a significant problem worldwide; however, understanding of its epidemiology is limited. Some investigators in the United States have estimated the prevalence of constipation to be 1.2% to 8.0% in the general population. In Brazil, some have found a pre

Quality assessment of drug use in the elderly

Abstract: OBJETIVO: Avaliar a qualidade do uso de medicamentos atraves da analise do padrao do uso, do grau de concordância com listas de medicamentos essenciais, do valor terapeutico e das interacoes medicamentosas encontradas entre mulheres com mais de 60 anos. METODOS: Foram pesquisadas 634 mulheres que frequentam a Universidade Aberta da Terceira Idade da Universidade do Estado do Rio de Janeiro. Os dados foram coletados atraves de questionario padronizado e testado. As variaveis utilizadas foram relativas aos medicamentos e a seu modo de utilizacao. As unidades de analise foram o medicamento e o individuo. RESULTADOS: Das 634 mulheres estudadas, 9,1% nao tomam qualquer tipo de medicamento. A media de medicamentos consumidos foi de 4,0 por mulher. Das 2.510 especialidades farmaceuticas citadas, ha 538 principios ativos diferentes. Cerca de 26% dos medicamentos sao concordantes com as recomendacoes da Organizacao Mundial da Saude, e 17%, com as da Relacao Nacional de Medicamentos Essenciais. Cerca de 17% dos medicamentos sao inadequados para o uso. No que diz respeito a redundâncias, 14,1% das mulheres podem sofrer consequencias decorrentes desse evento. Quanto as interacoes medicamentosas, 15,5% das entrevistadas estao expostas as principais interacoes. CONCLUSOES: Os dados sugerem que o padrao do uso dos medicamentos entre as idosas e bastante influenciado pela prescricao medica e que sua qualidade e prejudicada pela baixa seletividade do mercado farmaceutico.

Conseqüências da violência familiar na saúde da criança e do adolescente: contribuições para a elaboração de propostas de ação

Abstract: No Brasil, o conhecimento sobre a dimensao da violencia familiar e ainda escasso. Todavia, existem evidencias apontando para um cenario merecedor de enfrentamento imediato. Nesta perspectiva, o presente artigo destaca o campo das investigacoes sobre o tema, procurando explicitamente fazer uma ponte entre a apropriacao do conhecimento gerado e efetivas propostas de acao. O artigo divide-se em cinco partes. Inicialmente, e discutida a importância da violencia familiar no cenario de morbi-mortalidade de criancas e adolescentes A seguir, procura-se mapear as principais linhas de investigacao sobre o tema, sugerindo uma tipologia de estudos da area. A terceira sessao explora com mais enfase as investigacoes que avaliam as consequencias do fenomeno na saude de criancas e adolescentes. Na quarta secao, sao discutidos os possiveis elos entre o conhecimento a ser gerado nesse âmbito e as propostas de acao para o enfrentando da violencia familiar. Na ultima secao, sao feitas algumas consideracoes sobre a importância do enfoque familiar em oposicao ao individual; do multidisciplinar, em vez da abordagem compartimentalizada; e sobre a necessidade de integracao das varias agencias e servicos envolvidos com a violencia familiar.

Search for charged Higgs bosons in decays of top quark pairs

Abstract: We present a search for charged Higgs bosons in decays of pair-produced top quarks using 109.2{plus_minus}5.8 pb{sup {minus}1} of data recorded from p{ovr p} collisions at {radical}(s)=1.8 TeV by the D0 detector during 1992{endash}1996 at the Fermilab Tevatron. No evidence is found for charged Higgs production, and most parts of the [M{sub H{sup +}} {beta}] parameter space where the decay t{r_arrow}H{sup +}b has a branching fraction close to or larger than that for t{r_arrow}W{sup +}b are excluded at 95{percent} confidence level. Assuming m{sub t}=175 GeV and {sigma}(p{ovr p}{r_arrow} t{ovr t})=5.5 pb , for M{sub H{sup +}}=60 GeV , we exclude tan{number_sign}{beta}{lt}0.97 and tan{number_sign}{beta}{gt}40.9 . {copyright} {ital 1999} {ital The American Physical Society}

Behaviour, habitat use and population size of Sotalia fluviatilis (Gervais, 1853) (Cetacea, Delphinidae) in the Cananéia estuary region, São Paulo, Brazil

Abstract: From March 1987 to February 1988, Sotalia fluviatilis population size was estimated and behavioral patterns were observed in the Cananeia estuary region, in Southeast Brazil. Field observations were carried out from shore (40, with a mean observation period of 7.76 ± 2.05 hours a day, completing a total of 310.5 hours) and during line transect surveys by boat (55, 10 of them with a mean observation period of 4.44 ± 0.15 hours each and 45 with a mean observation time of 20 minutes, in the totality 64.3 hours). Dolphins occur in this region all year round, most commonly in small groups, with a greater number observed in January 1988, with no seasonal occurrence pattern. Pairs accounted for ca. 30% and calves were seen year round, always accompanied by one or more adults. Juveniles were slightly more common from July to February. More dolphins were seen from 9:00 a.m. to 10:00 a.m. (60.8%) until midday. From fourteen behavioral patterns identified, travelling (46.8%) and feeding (33.9%) were the most frequently observed. Group size and composition differed in each behavioral pattern. Diurnal migration was observed, related with hour and not to tide conditions. Dolphins were seen throughout the estuary. For the whole survey area, population density () was 3.38 ± 1.76 individuals/km2, dolphin abundance was found to be 704.8± 367.7 along 10 line transect from April 1987 from, where 82 km were surveyed. In Trapande Bay, the largest part of the studied area, equaled 12.4 ± 10.3 individuals/km2 in the morning and 16.4 ± 13.8 individuals/km2 in the afternoon.

[Leprosy epidemiology in a cohort of household contacts in Rio de Janeiro (1987-1991)].

Abstract: This study aimed to identify factors influencing the development of leprosy (Hansen's disease) in household contacts. A dynamic cohort was analyzed from 1987 to 1991 at the Hansen's Disease Department of the Oswaldo Cruz Foundation in Rio de Janeiro. The incidence rate was 0.01694 person-years of follow-up. Nevertheless, for subjects at the end of the first year of follow-up the incidence rate was 0.06385 (end of second year, 0.03299; end of third year, 0.02370; end of fourth year, 0.018622; and end of observation period, 0.01694). A stepwise multivariate logistic regression model was proposed to study the risk of developing leprosy, including co-prevalent cases, totaling 758 contacts. In the final model, the risk was associated with a negative Mitsuda skin test (OR = 3.093; CI 95% = 1.735-5.514), prior BCG vaccination (OR = 0.3802; CI 95% = 0.2151-0.66719), and multibacillary primary clinical form (OR = 2.547; CI 95% = 1.249-5.192). The results showed that both multibacillary leprosy and specific immune status are significant indicators for developing the disease in a cohort of household contacts.

Organochlorines and breast cancer: a case-control study in Brazil.

Abstract: Breast cancer is an important cause of morbidity and mortality in Brazil. Some studies have analyzed the potential role of organochlorine compounds in breast cancer etiology. These chemical compounds have been widely used in agriculture and in vector-control programs in Brazil. A case-control study was carried out in the main cancer hospital of the Instituto Nacional de Câncer in Rio de Janeiro to investigate exposure to organochlorinated pesticides as a risk factor for breast cancer. We investigated 177 cases of invasive breast cancer at the hospital, between May 1995 and July 1996, and 350 controls selected among female visitors at the same hospital. In addition to information obtained from interviews, blood samples were taken, to analyze residual amounts of organochlorine by gas chromatography using an electron capture detector. [1,1-Dichloro-2, 2-bis(p-chlorophenyl)ethylene] (DDE) was determined in sera of 457 women from a total of 493 participants who had serum samples available. Residues of hexachlorobenzene were found in 11 women only. No statistically significant association was found between breast cancer risk and serum level of DDE or history of exposure to pesticides. Serum levels of DDE (ng/ml) were similar in patients (median = 3.1, mean = 5.1) and controls (median = 3.1, mean = 4.8) (p = 0.93). The age-adjusted odds ratio of breast cancer for women in the upper quintile compared with those in the lowest quintile was 0.90 (95% confidence interval 0.47-1.73). When adjusted for other variables, the risk remained not statistically significant (upper quintile odds ratio = 0.79, 95% confidence interval 0.39-1.60). In our hands, exposure to organochlorinated pesticides measured by history or serum analysis was thus not a risk factor for breast cancer.

Estrutura vegetal e grau de perturbação dos manguezais da Lagoa da Tijuca, Rio de Janeiro, RJ, Brasil

Abstract: The Tijuca Lagoon is located south of Rio de Janeiro City It is bordered by a discontinued and narrow belt of mangrove trees Mangrove forests have a high structural variability Of the eighteen stands studied there are monospecifics stands of Laguncularia racemosa with dbh between 34 and 77 cm and height between 45 and 77 m, dominated by trees with dbh less than 100 cm At the other stands, occur mixed forests, structuraly more developed, sometimes dominated by Laguncularia racemosa, sometimes by Rhizophora mangle (dbh between 78 and 167 cm; height between 68 and 161 m, prevailing trees with dbh greater than 100 cm) There are also mixed stands dominated by Avicenia schaueriana (dbh of 71 cm and 53 m high, predominating individuals over 100 cm in dbh) The structural variability observed, is strong evidence of an altered landscape Observations on mangrove forests at southeastern Brazil show that stands dominated by Laguncularia racemosa with low dbh are typical of degraded sites in process of restoration The structure that is quite close to that of the original forest is represented by the most developed stands (high dbh and height) One of the studied stands, with mature forest of Rhizophora mangle, high developed for the structural patterns of mangrove at the southeastern Brazil is jeopardized by the invasion of Acrostichum sp, wich is preventing the development of Rmangle saplings This invasion is related to a high deposition of mud, wich rose the substrate, reducing tide inundation

Chagas disease: from bush to huts and houses. Is it the case of the Brazilian amazon?

Abstract: Two of the major problems facing the Amazon - human migration from the other areas and uncontrolled deforestation - constitute the greatest risk for the establishment of endemic Chagas disease in this part of Brazil. At least 18 species of triatomines had been found in the Brazilian Amazon, 10 of them infected with Trypanosoma cruzi, associated with numerous wild reservoirs. With wide-range deforestation, wild animals will perforce be driven into other areas, with tendency for triatomines to become adapted to alternative food sources in peri and intradomicilies. Serological surveys and cross-sectional studies for Chagas disease, carried out in rural areas of the Rio Negro, in the Brazilian Amazon, showed a high level of seropositivity for T. cruzi antibodies. A strong correlation of seroreactivity with the contact of gatherers of piacava fibers with wild triatomines could be evidenced.

Induction of NOS in rat blood PMN in vivo and in vitro: modulation by tyrosine kinase and involvement in bactericidal activity.

Abstract: Intravenous administration of lipopolysaccharide (LPS) to rats increased the production of nitric oxide (NO) metabolites (NOx) by blood polymorphonuclear neutrophils (PMN) in vitro. Both dexamethasone and L-NMMA, added in vitro to neutrophil cultures, inhibited the production of NO. On the other hand, the production of NO was not affected by the treatment, in vivo or in vitro, with different inhibitors of cyclooxygenase or 5-lipoxygenase or with a platelet-activating factor (PAF) antagonist. The incubation of blood PMN from normal rats in vitro with neutrophil activators (PAF, leukotriene B4, and interleukin-8) and different cytokines [interleukin-1, tumor necrosis factor alpha, and interferon-gamma (IFN-gamma)] showed that only IFN-gamma was able to induce the production of high amounts of NO. This induction was directly correlated with the expression of iNOS and an increase in in the enzyme activity in blood PMN. The tyrosine kinase inhibitor genistein inhibited NO production induced by IFN-gamma, suggesting that the signal transduction pathway leading to NOS induction in rat PMN involves phosphorylation by tyrosine kinase. We also showed that NO produced by IFN-gamma activated rat blood PMN involved in the killing of Pseudomonas aeruginosa.