Search PubMed⌕ Search

Biomedical subjects

C S Ferreira

Publications and source records attributed to C S Ferreira.

At least 19 recordsLinked to original sources
PubMed2004

[Action-oriented information systems: subsidies for activities by workers' health programs at the local level].

Over the course of recent decades, Brazil has become an industrialized society. From an epidemiological perspective and considering changes that have been occurring in the Brazilian population, particularly concerning demographic and epidemiological transitions, this paper discusses the need to adapt the epidemiological surveillance system in order to incorporate the surveillance of non-transmissible diseases. The authors analyze the information system for work-related accidents in the Workers' Health Program, under SUDS (the Unified Decentralized Health System) for the Mandaqui Region (in the Northern part of the city of São Paulo), based on data from a local metalworking industry identified by the information system as a high-risk site for work-related accidents. The article also focuses on the importance of organized workers participating in actions to control work-related accidents. Although such participation is not always possible, the health sector must incorporate the workers' own concrete experience in order to develop more effective actions to prevent accidents at the workplace.

English Abstract↗
PubMed2002

Intestinal parasitic infections in young children in São Paulo, Brazil: prevalences, temporal trends and associations with physical growth.

The prevalences of intestinal parasitic infections were investigated, between 1995 and 1996, in a household-based sample of 1044 children aged <5 years who lived in the city of São Paulo, Brazil. Only 10.7% of the children were infected, the most prevalent parasites being Giardia duodenalis (5.5%), Ascaris lumbricoides (4.4%) and Trichuris trichiura (1.0%). A comparison between these data and results from two previous population-based surveys, completed in São Paulo in 1974 and 1985, revealed a dramatic decrease in the prevalence of intestinal helminths in this age-group, with less marked changes in the prevalence of Giardia, over the two past decades. Despite the low prevalence of malnutrition (2.4% of stunting and 0.6% of wasting) and intestinal parasites in this population, there was a significant association (P=0.05, after controlling for potential confounding variables) between helminth (but not Giardia) infection and height. The helminth-infected children had a mean height-for-age z-score of-0.412 [95% confidence interval (CI)=-0.637--0.186], compared with one of 0.015 (CI=-0.049-0.079) for the non-infected children. No significant relationship between intestinal parasitic infection and children's weight was detected. In conclusion, a small but significant negative relationship between intestinal helminthic infections and children's growth was detected in an urban environment with low prevalences of both intestinal parasitic infection and malnutrition.

Age Distribution↗
PubMed2001

Virulence properties of Escherichia coli isolated from ostriches with respiratory disease.

Eight Escherichia coli isolates from ostriches with respiratory disease were investigated for the presence of genes encoding the following adhesins: type 1 pili (fim), pili associated with pyelonephritis (pap), S fimbriae (sfa), afimbrial adhesin (afaI), temperature regulated adhesin, curli (crl, csgA) and temperature-sensitive hemagglutinin (tsh). Genes for heat labile (LT) and heat stable (STa and STb) enterotoxins, Shiga toxins (stx1 and stx2), cytotoxic necrotizing factor 1 (cnf), alpha-haemolysin (hly) and aerobactin (aer) production were also investigated. Other characteristics investigated were the presence of hemagglutination activity, growth on an iron-deficient medium, aerobactin production, serum resistance, adherence to chicken tracheal cells, pathogenicity for day-old chicks, and serogroup. Serogrouping showed that four isolates belonged to serogroup O2, two to serogroup O78, one to serogroup O9, and one to serogroup O21. The virulence genes found were: fim in all eight isolates, csgA in seven, aer in six, and pap, crl and tsh in one isolate each. All isolates analyzed were positive for mannose-resistant hemagglutination, adhered in vitro to ciliated tracheal epithelium, grew on iron-deficient medium, and showed serum resistance. Pathogenicity tests on day-old chickens revealed one highly pathogenic isolate, three of low pathogenicity and four isolates with intermediate pathogenicity.

Adhesins, Escherichia coli↗
PubMed2001

Glutathione-induced conversion of pentavalent antimony to trivalent antimony in meglumine antimoniate.

The standard treatment of human leishmaniases involves the use of pentavalent antimony [Sb(V)] compounds, including meglumine antimoniate. The mode of action of these compounds has not been fully elucidated. The possibility that Sb(III) is involved has been suggested; however, the biomolecule that may induce the conversion of Sb(V) to Sb(III) has not yet been identified. In the present study, we investigated both the ability of reduced glutathione (GSH) to promote the reduction of Sb(V) into Sb(III) in meglumine antimoniate and the effects of pH and temperature on this transformation. GSH did promote the reduction of Sb(V) into Sb(III) in a dose-dependent manner. When GSH and meglumine antimoniate were incubated together at a GSH/Sb molar ratio superior or equal to 5:1, all antimony was encountered in the reduced form, indicating a stoichiometry of 5:1 between GSH and Sb(V) in the reaction. The reaction between Sb(V) and GSH was favored at an acidic pH (pH 5) and an elevated temperature (37 degrees C), conditions found within the phagolysosome, in which Leishmania resides. For instance, about 30% of the Sb(V) (concentration, 2mM) was converted to Sb(III) following incubation for 3 days with 10 mM GSH at pH 5 and 37 degrees C. Our data support the hypothesis that Sb(V) would be converted by GSH, or a related thiol compound, to more toxic Sb(III) in the phagolysosome of macrophages.

Antimony↗
PubMed2000

[Seroprevalence of Triatoma infestans Chagas disease after vector control measures].

INTRODUCTION: The study is part of a project intended to retrieve information about the serology of the American trypanosomiasis in the state of São Paulo, Brazil, during the period when there was a state effort to control the vector. Data from the municipality of Taquarituba, administrative region of Sorocaba, which was then important in the epidemiology of Chagas disease in that region, were analyzed. Despite the government efforts started in the 1950s, domiciliary triatomines were still being captured in that region during the 1970s. METHODS: Population samples were selected from five localities of Taquarituba. Age, sex, birthplace, and time of residence in the house being occupied at the time of the interview, were recorded. It is used Probit analysis to assess a possible relationship between age and seropositivity, the latter taken as indicative of the risk of transmission. RESULTS: Blood from Taquarituba native people represented 62.9% of the samples examined (n = 2.784) and 62.4% of all seropositives (n = 380). Overall proportion of seropositives was 13.6% with no significant difference between genders (p = 0.538). Children under 6 years of age were not seropovitive, Seropositivity increased from 2.7% in the age group 6-9 years to 30.6% in the age group 30-39 years. By using probit analysis, an age-seropositivity relationship was found within these groups. CONCLUSIONS: The results of serological tests pointed to an association between the actions taken against Triatoma infestans and the decline and eventual control of the transmission of Chagas disease in the late 1960s.

Adolescent↗
PubMed2000

[Secular trends in intestinal parasitic diseases of childhood in the city of São Paulo, Brazil (1984-1996)].

OBJECTIVE: Data from two consecutive household surveys undertaken in mid-80s and mid-90s allow to characterize and analyse secular trends in infant and child intestinal parasitic diseases in the city of S. Paulo, Brazil. METHODS: The two surveys included random population samples aged from zero to 59 months (1,016 in the period of 1984-85 and 1,280 in 1995-96). Stool samples were collected in both surveys and examined by sedimentation techniques using both unstained and Lugol-stained preparations. For each survey, the study of the social distribution of the parasitic diseases took into account tertiles of the per capita family income. For the study of the determinants of secular trends, hierarchical causal models, multivariate regression analyses and calculations analogous to the ones used to assess population attributable risks were applied. RESULTS/CONCLUSIONS: In the time span from the first to the second survey, there was a substantial reduction in the prevalence of all parasites (from 30.9% to 10.7%), helminths in general (from 22.3% to 4.8%), giardiasis (from 14.5% to 5.5%) and two or more species of parasites (from 13.1% to 0.5%). A significant decline in prevalence was observed in all social strata and the inverse association between income and intestinal parasites was kept unchanged in the period. Positive changes in distal (family income and maternal schooling) and intermediate determinants (housing, sanitation, and access to health care) of helminthic disease could substantially explain part of its decline in the period. The decline in giardiasis was attributed to improvement in maternal schooling, housing and sanitation. The duplication in the attendance rate to day care nurseries may have restricted the decline rate in the giardiasis prevalence in the study period.

Brazil↗
PubMed1999

The aortic valve with two leaflets--a study in 2,000 autopsies.

Our study is based on the examination of 2,000 aortic valves obtained from fresh cadavers (1,499 males, 501 females) at the Institute of Forensic Medicine in Rio de Janeiro. We discovered 13 valves having two leaflets, giving a prevalence of 0.65%, much lower than generally reported in the literature. All 13 valves were from males, 10 from whites, three from mulattos, and none from blacks. Special attention was given to the raphe and the leaflets, the calcification of which can lead to stenosis. The only valves with normal texture and flexibility were two obtained from children less than one year old. All the other valves were thickened, and five of them had some degree of calcification. Six valves were judged to be functioning normally, while 7 valves were abnormal, 5 being stenotic and two showing evidence of insufficiency. The insufficiency in one was due to endocarditis, but in the other was due to redundancy of the leaflets. The only other cardiac anomaly discovered in these 13 cases was one patient with aortic coarctation. Bifoliate aortic valve, therefore, is probably the most common cardiac anomaly, although its prevalence as discovered in Brazil is lower than that reported in the literature. It affects mainly white males. After the fourth decade of life, most valves present some thickening, with stenosis being the most common complication. As is well recognised, infective endocarditis and aortic insufficiency are the other frequent complications. It is in general, nonetheless, an isolated anomaly.

Adult↗
PubMed1998

Interobserver agreement in assessing plain radiographs of maxillary sinus.

Interrater agreement of six observers in interpreting maxillary sinus plain X-ray films was assessed. Patients aged 1-15 years old were enrolled and X-rays in the Caldwell and Waters's views were requested to confirm diagnosis of sinusitis or after antimicrobial therapy for a pre-existing sinusitis. One-hundred and one pairs of maxillary sinus radiographs from 101 patients were submitted to an independent and blind interpretation by three radiologists and three pediatricians. Each maxillary sinus was separately analyzed. Kappa statistic was used to measure interobserver agreement. A fair degree of agreement among the six raters was found on analyzing these films: 0.39 (95% CI, 0.36-0.41) for the right maxillary sinus and 0.37 (95% CI, 0.34-0.39) for the left one. These results stress literature data on the limits of plain radiographs for diagnosing maxillary sinusitis. The necessity of knowing the clinical findings while interpreting the exams also was depicted.

Adolescent↗
PubMed1997

Experimental infestation of Gallus gallus with Ornithodoros (Alectorobius) amblus (Ixodoidea: Argasidae).

Ornithodoros (Alectorobius) amblus Chamberlin 1920 specimens were collected from a seagull (Larus spp.) nest in northern Chile. This reports the occurrence of this species outside Peru. The biology of 79 specimens reared under laboratory conditions at 27 degrees C, 75-80% RH, and total darkness was determined. A 13% mortality rate from larval to adult was observed. Larval ticks were fed on chicks, Gallus gallus domesticus; and nymphs and adults were fed on chickens. We recorded the number of eggs per female per gonotrophic cycle and the mean duration of the periods of preoviposition, oviposition, and incubation. The total duration of their life cycle ranged from 111 to 239 d, depending on the number of molts. Males were found after the 4th molt, and after the 5th molt the proportion of females was greater than that of males or remaining nymphs. The feeding period of larvae was 4-6 d, N1 nymphs do not feed. The N2-N6 nymphs, males and females, had a 10- to 60-min feeding period. From N2 on, there was emission of coxal fluid while on the host and during or immediately after feeding.

Animals↗
PubMed1997

Benzathine penicillin for unilateral lobar or segmental infiltrates presumptively caused by Streptococcus pneumoniae in children 2-12 years old.

A randomized controlled study was carried out to assess the efficacy of a single dose of benzathine penicillin for treating children 2-12 years old with presumed S. pneumoniae pneumonia. One-hundred-and-seventy-six children screened at self-referral pediatric emergency services in Belo Horizonte, Brazil, were randomized to only one injection of benzathine penicillin (n = 93, case-group) or a 7-day procaine penicillin regimen (n = 83, control-group), upon diagnosis of pneumococcal pneumonia based on clinical and radiological characteristics. Follow-up was carried out on the second day after treatment and around the 7th and/or 14th day after treatment allocation. No statistical significant difference was found for sociodemographic, clinical, laboratory or radiographic characteristics among the two groups. Evident or total radiographic clearing was demonstrated for 92.3 and 95.1 per cent of the benzathine penicillin and procaine penicillin groups, respectively (P = 0.54). Benzathine penicillin may be considered an alternative to classic regimens for treating pneumonia due to sensitive strains of S. pneumoniae among children 2-12 years old. Other benefits are its lower cost, better compliance and low rates of adverse reactions.

Chi-Square Distribution↗
PubMed1996

Rapid epidemiologic assessment of breastfeeding practices: probit analysis of current status data.

We describe the use of probit analysis to estimate breastfeeding indicators from current status epidemiological data. A health centre-based sample of 2411 children aged 0-1 year was investigated in Santo Andre, a large town in the Metropolitan Area of Sao Paulo, southeastern Brazil. Mothers were interviewed during routine pediatric consultations and asked about their current infant feeding practices. Probit regressions were calculated by a public-domain microcomputer programme written by one of us. The median duration of total (i.e. exclusive plus partial) breastfeeding in this children's sample, estimated as 108.8 days (95 per cent confidence interval: 95.5-123.2 days), is close to that recently reported in the city of Sao Paulo and nearby towns. However, the median duration of exclusive breastfeeding (28.9 days, 95 per cent CI: 17.9-38.3 days) is rather short when compared to recent estimates from this same region. Despite the nationwide efforts for promotion of exclusive breastfeeding, only 14 per cent (95 per cent CI: 12.3-17 per cent) of the infants were still being exclusively breastfed by 120 days of age. Therefore, a key feature of breastfeeding practices in this population sample, namely, the early introduction of supplementary foods, was identified by using simplified methods of data collection and analysis. This communication suggests that probit analysis of current status data may be further explored as a method for rapid epidemiologic assessment of breastfeeding practices.

Brazil↗
PubMed1994

The prevalence of infection by intestinal parasites in an urban slum in São Paulo, Brazil.

Sedimentation parasitological examinations were performed in stool specimens from a random household-based sample of 407 dwellers, all age groups being represented, in a slum of São Paulo, south-eastern Brazil. Intestinal parasites were detected in 45.7% of the specimens. The most prevalent parasites in this population were Ascaris lumbricoides (23.8%) and Trichuris trichiura (17.2%); only 17 individuals (4.2%) harboured Giardia duodenalis and 6 (1.5%) harboured Entamoeba histolytica. Taenia and hookworm eggs were not found. Simultaneous infection by A. lumbricoides and T. trichiura was diagnosed in 34 subjects (8.4%). The prevalence rates of infection by A. lumbricoides and T. trichiura (including those of mixed infections by both species) were highest among children aged 2-12 years. In samples positive for A. lumbricoides and/or T. trichiura, egg counts were done on Kato's thick smears and the results expressed as eggs per gram faeces (e.p.g.). The mean intensity of infection (measured as e.p.g.) in A. lumbricoides-infected subjects was highest among children aged 6-12 years and young adults under 25 years, while in T. trichiura-infected subjects the highest egg counts were observed in children aged 2-12 years. The frequency distributions of eggs of both nematodes passed by the host population were overdispersed. Moreover, a strong positive correlation (P < 0.0001) was observed between counts of eggs of both species passed by the same hosts.

Adolescent↗
PubMed1992

[Sick building syndrome in bank employees].

This study seeks, for the first time, to identify the sick building syndrome in Brazil. The study population consisted of 312 bank-clerks distributed in two closed buildings situated in S. Paulo city, Brazil. Data were collected by questionnaire, the design was cross-sectional and analysis made by logistic regression. Female, job satisfaction and inappropriate temperature were related to general symptoms. Female and inappropriate temperature were related to mucus membrane symptoms. Job satisfaction was related to absenteeism.

Air Pollution, Indoor↗
PubMed1991

A simple reflectance microphotometer for dot immunobinding assay (dot-ELISA) quantification.

The use of a simple reflectance microphotometer adapted to quantify enzymatic dot immunobinding assays is described. The instrument is versatile and precise by clinical laboratory standards (i.e., 1.1% coefficient of variation for ten consecutive readings of a grey cardboard). The instrument provides a low-cost alternative to commercially available equipment for quantitation of dot-ELISA assays.

Animals↗