Dispersal mode constrains allocation of carbon and mineral nutrients in seeds of forest and savanna trees

Species vary in seed size and content of stored reserves, which can be related to dispersal strategies and type of habitat in which they are found. We compare seed carbon and nutrient reserves of anemochorous and zoochorous trees from the Cerrado of central Brazil. We measured seed dry mass, lipids, non-structural carbohydrates (starch and total soluble sugars), carbon and mineral nutrients in ten forest and 13 savanna species, each classified as having wind- or animal-dispersed seeds. We used phylogenetically independent contrasts to test for correlations among these traits. Seeds of anemochorous species were lighter, with higher concentrations of C, N, P, Ca and Mg. Lipids were the dominant carbon reserve for most anemochorous species, underpinning the importance of allocation to compact carbon reserves. Starch, lipids or soluble sugars were the major carbon reserve in zoochorous seeds. Savanna and forest species did not differ in seed mass or in total carbon reserves. However, seeds of forest species had higher concentrations of starch than seeds of savanna species. Lipid and starch negatively correlated across species, suggesting a trade-off between starch and lipids as major seed carbon reserves. Calcium was positively correlated with Mn and B, while Mg was positively correlated with C, N, P, K, S, Zn and B. Potassium, S and Cl were positively correlated, while P was positively correlated with Mg and Zn. Dispersal mode rather than vegetation type constrained seed mass and seed storage allocation patterns in forest and savanna trees. We provide evidence that similar mechanisms are involved in seed storage of carbon and mineral nutrients across species.

Caries prevalence and treatment needs in young people in Portugal: the third national study

OBJECTIVE

To evaluate caries prevalence and dental treatment needs in Portuguese children and teenagers, as well as fluorosis prevalence in 12-year-old children, in order to address public oral health program strategies.

PARTICIPANTS

A representative stratified random cluster sample of 3,710 participants of 6, 12, and 18 years old was selected. A questionnaire was applied to determine sociodemographic data and some oral health determinants. The clinical examination was based on the ICDAS criteria, then adapted to DMFS index, and Dean's index for fluorosis.

RESULTS

Caries prevalence at 6, 12, and 18 years old was 45.2%, 47.0%, and 67.6%, respectively. D₅MFT scores were 1.18 (SD 0.06) and 2.51 (SD 0.10), respectively. Treatment needs at 12 and 18 years old were associated with 0.37 (SD 0.03) and 0.75 (SD 0.06) values in the "decayed" (D₅) variable. SiC index at 12 years old was 2.68 (SD 1.68). Sealants were identified in 55% of 12-year-old children and the mean of sealants per individual was 3.61; also, moderate (2.2%) and severe (0.2%) levels of fluorosis were detected.

CONCLUSIONS

The oral health situation in Portugal is favorable for young people, resulting in low treatment needs. The National Oral Health Promotion Program should be extended to include 18-year-olds.

Assessment of control and epidemiologic details of the schistosomiasis mansoni in Bananal, São Paulo, Brazil

The purpose of our study in the municipality of Bananal, state of São Paulo, Brazil, was to stop the transmission of schistosomiasis mansoni. Particular emphasis was given to such items as the active surveillance and eventual treatment of hosts, mapping parasite foci, and increasing the extent of basic sanitation in the municipality. Now, our records indicate that the eradication of schistosomiasis in the municipality of Bananal is attainable. However, as the vector Biomphalaria tenagophila can still be found in some water bodies within this municipality, it remains included in the area where schistosomiasis is endemic, which calls for very strict measures to avoid the human cases of schistososomiasis. The expansion of the coverage of the basic sanitation network and treatment of Schistosoma mansoni cases diagnosed during periodic surveys are part of the plans to eradicate schistosomiasis in Bananal.

Cryopreservation does not alter karyotype, multipotency, or NANOG/SOX2 gene expression of amniotic fluid mesenchymal stem cells

Cryopreservation of mesenchymal stem cells from amniotic fluid is of clinical importance, as these cells can be harvested during the prenatal period and stored for use in treatments. We examined the behavior of mesenchymal stem cells from human amniotic fluid in culture that had been subjected to cryopreservation. We assessed chromosomal stability through karyotype analysis, determined whether multipotent capacity (differentiation into adipogenic, chondrogenic, and osteogenic cells) is maintained, and analyzed SOX2 and NANOG expression after thawing. Five amniotic fluid samples were cryopreserved for 150 days. No chromosomal aberrations were observed. The expression levels of NANOG and SOX2 also were quite similar before and after cryopreservation. Capacity for differentiation into adipogenic, chondrogenic, and osteogenic tissues also remained the same. We conclude that cryopreservation of amniotic fluid does not alter karyotype, NANOG/SOX2 gene expression, or multipotent capacity of stem cells that have been collected from amniotic fluid during pregnancy.

Abdominal ultrasound in the evaluation of fibrosis and portal hypertension in an area of schistosomiasis low endemicity

This study was undertaken in the municipality of Bananal, São Paulo, an endemic area for schistosomiasis with a prevalence under 10% and low parasite load among infected individuals. Our objective was to identify the clinical forms of schistosomiasis among 109 patients in whom the disease had been diagnosed through direct fecal analysis and who had been medicated with oxamniquine at the time of the Plan for the Intensification of Schistosomiasis Control Actions (1998-2000). These patients were submitted to an abdominal ultrasonography and fecal analysis by Kato-Katz method, four years, on average, after the end of the Plan. Five patients, whose abdominal ultrasound images were compatible with either peripheral or central periportal fibrosis and portal hypertension, were identified. None of the 109 patients presented Schistosoma mansoni eggs at fecal analysis. Ultrasonography is a sensitive, noninvasive diagnostic method that allows a better identification of the extent of liver involvement in schistosomiasis cases.

Observações sobre o TESA blot no diagnóstico sorológico da doença de Chagas

Comparamos o TESA blot com a hemaglutinação indireta, imunofluorescência indireta e ELISA. Nos 30 soros de pessoas infectadas pelo Trypanosoma cruzi, as quatro técnicas foram positivas em todos, e nos 30 não-infectados, totalmente negativas. Nos soros indeterminados e nos de leishmaniose visceral, comprovamos muitas positividades falsas, em quantidade bastante menor com o TESA blot.

Avaliação da eficácia da azitromicina e pirimetamina em camundongos infectados por cepa cistogênica de Toxoplasma gondii

Foi avaliada a eficácia da administração prolongada de azitromicina e pirimetamina em camundongos infectados com cepa cistogênica de Toxoplasma gondii. Os animais foram inoculados intraperitonealmente com um cisto de T. gondii e, após 20 dias, divididos em quatro grupos: GI infectados não tratados, GII infectados e tratados concomitantemente com pirimetamina (12,5mg/kg/dia) e azitromicina (100mg/kg/dia), GIII infectados e tratados com a mesma dose de pirimetamina e GIV infectados e tratados da mesma forma com azitromicina. O tratamento, via oral, estendeu-se por 120 dias; após este período os animais foram sacrificados e foi feita a contagem dos cistos no cérebro. A associação de ambos os medicamentos proporcionou melhores resultados, diminuindo a contagem de cistos no cérebro dos animais tratados de forma concomitante.

Elevada porcentagem de blastocistose em escolares de São Paulo, SP

Em exame parasitológico de fezes de 227 alunos de escola pública de São Paulo (SP), encontramos 87 (38,3%) positivas para Blastocystis hominis. A blastocistose ainda suscita controvérsias e indefinições, merecedoras de esclarecimentos sobretudo para evitar contratempos no âmbito da saúde pública e das atenções médico-assistenciais.

[The efficiency of the examination of compressed fecal samples for Schistosoma mansoni eggs]

The control of schistosomiasis depends mostly upon the sensitivity of stool examinations. We used both the Kato-Katz technique and the compression of samples between the slide and a polypropylene cover glass, according to Ferreira. Out of 1,282 samples collected between 1998 and 2000 in the Palha District, Municipality of Bananal, São Paulo State, Brazil, 105 (8.2 %) were positive. The first and second methods revealed 90 (7%) and 88 (6.9 %) positive cases, respectively. According to the kappa statistic, both methods were in agreement. In Bananal, the proportion of positive cases and egg per gram (epg) values are low, which calls for the examination of larger than usual volumes of feces. The viability of Schistosoma mansoni eggs can also be checked when using the second method, which dispenses with glycerin solution, measuring plates and sieves. The latter cause a further loss of precision in epg determinations.

[Blastocystosis: controversy and indefinedness]

Blastocystosis is the infection caused by Blastocystis hominis. It is associated with frequent and unquestionably very important controversy and lack of definition, above all due to its implications for general assistance and medical care. In that connection, there is considerable disagreement on the subject of the pathogenicity of this protozoan, which should be categorically defined. Other aspects besides the above, require clarification through results from well conducted studies aiming at attributing Blastocystis hominis a proper role within the context of public health. Another matter worthy of attention is the diagnostic value of the parasitological stool examination, with the proviso that it is adequate, as are fecal smears suspended in saline solution or permanent mounts stained with iron hematoxylin or thionine. The use of inadequate techniques tends to produce false negative results, thereby impeding investigation into the real importance of this microorganism.

Schistosomiasis mansoni in Bananal (State of São Paulo, Brazil): I. Efficiency of diagnostic and treatment procedures

Bananal is an important focus of Schistosoma mansoni in the State of São Paulo. Accordingly, programmed active search for human cases, annual coproscopic surveys and treatment of infected cases were started in 1998, aiming at producing a sharp prevalence rate drop by the year 2000. S. mansoni eggs were searched for in two Kato-Katz slides per patient. Cases were followed up according to the routine of the local Family Health Program. In 1998, 130 samples out of 3,860 showed S. mansoni eggs; in 1999, 105 out of 3,550, and in 2000, 64 out of 3,528. Prevalence rates were 3.4%, 2.9%, and 1.8%, and average egg-counts 59, 64, and 79 eggs per gram of feces respectively. Prevalence rates decreased steadily after treatment, but persistently positive cases showed no significant decrease in parasite burdens. Egg count variation depended on sex and age bracket. Persistent residual cases admittedly preclude the eradication of this infection by only searching for and treating carriers. In addition, resistance to therapy and low sensitivity of fecal examinations, can not be ignored. Moderate to heavy worm burdens, frequently associated with hepatomegaly elsewhere, produced no serious cases in Bananal.

Schistosomiasis mansoni in Bananal (State of São Paulo, Brazil): II. Intermediate hosts

We conducted monthly snail captures in Bananal, State of São Paulo, Brazil, between March 1998 and February 2001, to identify Schistosoma mansoni vectors, estimate seasonal population changes, and delimit foci. We also evaluated the impact of improvements in city water supply and basic sanitation facilities. We identified 28,651 vector specimens, 28,438 as Biomphalaria tenagophila, 49 of them (0.2%) infected with S. mansoni, and 213 as B. straminea, none of the latter infected. Vectors predominated in water bodies having some vegetation along their banks. Neither population density nor local vegetation could be linked to vector infection. We found the first infected snails in 1998 (from March to May). Further captures of infected snails ocurred, without exception, from July to December, when rainfall was least. Irrespective of season, overall temperature ranged from 16.5 degrees C to 21 degrees C; pH values, from 6.0 to 6.8. Neither factor was associated with snail population density. Frequent contact of people with the river result from wading across it, extracting sand from its bottom, fishing, washing animals, etc. Despite a marked reduction in contamination, cercaria shedding persists. Whatever the location along its urban course, contact with river Bananal, particularly of the unprotected skin, entails risks of infection.

Microwave treatment of human milk to prevent transmission of Chagas disease

It is recognized that breast feeding is an alternative means of transmission of Chagas disease. However, thermal treatment of milk can prevent this occurrence. As domestic microwave ovens are becoming commonplace, the efficacy of microwave thermal treatment in inactivating Trypanosoma cruzi trypomastigotes in human milk was tested. Human milk samples infected with T. cruzi trypomastigotes (Y strain) from laboratory-infected mice, were heated to 63 degrees C in a domestic microwave oven (2,450 MHz, 700 W). Microscopical and serological examinations demonstrated that none of the animals inoculated orally or intraperitoneally with infected milk which had been treated, got the infection, while those inoculated with untreated, infected milk, became infected. It was concluded that the simple treatment prescribed, which can easily be done at home, was effective in inactivating T. cruzi trypomastigotes contained in human milk.

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.

Identification of Cryptosporidium spp. oocysts in fecal smears stained with Heidenhain's iron hematoxylin

There is no paucity of methods for diagnosing Cryptosporidium spp. infection. The merits of immunoassays notwithstanding, microscopic identification of Cryptosporidium spp. oocysts in fecal samples remains an important diagnostic procedure. It owes the persistence of its use to such characteristics as dispensing with expensive equipment and kits, requiring only basic laboratory facilities, and having a low probability of false positive results when permanent slides are prepared, which can be re-examined in case of doubt. Cryptosporidium spp. oocysts can be readily identified in fecal smears prepared according to a regressive iron hematoxylin staining technique. The number of steps and their duration, as well as costs, were reduced to a minimum without loss of image quality and permanence of the preparations.

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.

Pasteurization of human milk to prevent transmission of Chagas disease

Although admittedly transmission of Trypanosoma cruzi infection through breastfeeding is a rare event, it involves serious risks. To test the effectiveness of pasteurization in preventing this mode of infection, three sets of samples of human milk were tested: a - contaminated with T. cruzi and pasteurized; b - contaminated with T. cruzi and non-pasteurized; c - non-contaminated and pasteurized. Samples from all sets were orally and intraperitoneally administered to 90 BALB/c mice. The animals inoculated with contaminated, non-pasteurized samples, got the infection. Controls and the animals inoculated with contaminated and pasteurized milk were not infected. The hypothesis was accepted that pasteurization inactivates T. cruzi trypomastigotes.

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.

[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.

[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.

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.

Influence of refrigeration and formalin on the floatability of Giardia duodenalis cysts

Giardia duodenalis cysts obtained from fresh fecal samples, fecal samples kept under refrigeration and fecal samples treated with formalin were studied as to their floatability on sucrose solutions with the following specific gravities: 1,040 kg/m3; 1,050 kg/m3; 1, 060 kg/m3; 1,070 kg/m3; 1,080 kg/m3; 1,090 kg/m3; 1,100 kgm3; 1,150 kg/m3; 1,200 kg/m3; and 1,250 kg/m3, contained within counting-chambers 0.17 mm high. Cysts that floated on and those settled down as sediments were counted, and had their percentages estimated. Sucrose solutions of 1,200 kg/m3 specific gravity (the average specific gravity of diluting liquids employed in floatation techniques) caused to float 77.7%, 78.4% and 6.6% of the G. duodenalis cysts obtained, respectively, from fresh fecal samples, fecal samples kept under refrigeration, and fecal samples treated with formalin. Cysts obtained both from fresh fecal samples and fecal samples kept under refrigeration presented similar results concerning floatability. It was observed, however, that the treatment of feces with formalin diminished the cysts floatability under the various specific gravities studied. This results should influence, the recommendations for transport and storage of fecal samples used for parasitological coproscopy.

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.

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.

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.

Human infection with Trypanosoma cruzi in Nasca, Peru: a seroepidemiological survey

We estimated the proportion of seropositivity for infection with Trypanosoma cruzi (Chagas' disease) in a sample of the rural population of the Province of Nasca, Department of Ica, southwestern Peru. Although Triatoma infestans, the only vector species identified in the Department of Ica, is often found in domestic environments, data of the extent of human infection with T. cruzi are scant. This study comprised 446 houses, known to be infested with triatomines, distributed in 19 rural localities. While visiting those houses we collected filter paper bloodspots from 864 occupants (of both sexes, aged one year or over). By means of the indirect fluorescent antibody test (IFAT), we detected anti-T. cruzi IgG antibodies in samples from 178 individuals (20.6%). Seropositivity was significantly more frequent in females (23.8%) than in males (17.5%). Among the 410 individuals in the 1- to 10-year-old age group (47.5% of the population sample), 85 (20.7%) were found seropositive, which is indicative of an early acquisition of the infection. Within this group no significant differences in seropositivity were associated with sex.

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.

Pulmonary manifestations in the initial phase of schistosomiasis mansoni

The clinical and radiological pulmonary manifestations in the initial phase of schistosomiasis mansoni were studied in thirty previously healthy individuals who were simultaneously infected. The findings were compared with those concerning a control group and related to possible pathogenetic factors. The respiratory manifestations were of light or of moderate intensity, the dry cough being the most common symptom. The significant radiological alterations were: thickening of bronchial walls and beaded micronodulation, predominantly localized in the lower pulmonary fields. It was observed significant association between wheezing and IgE levels, estimated by the area of immediate intradermal reaction, as well as between the number of blood eosinophils and the occurrence of radiological changes. Moreover, there was correlation between the worm burden and the presence of wheezing, thoracic pain and beaded micronodulation. Thus, the clinical and radiological pulmonary manifestations described are significant part of the initial phase of schistosomiasis mansoni and present the worm burden, eosinophilia and levels of IgE as probable pathogenetic factors.

Avaliação de técnica de sedimentação em tubos

O rendimento de sedimentação em tubos, aplicada à pesquisa de ovos de Ancylostomidae, Trichuris trichura e Ascaris lumbricoides foi estudado em suspensões fecais diluídas a 2,0%; 1,5% e 1,0% em colunas de 80 mm de altura. De cada um dos helmintos citados, as amostras continham quantidades correspondentes a 12,5; 25,0; 50,0; 100,0; 150,0 e 200,0 ovos por grama de fezes (opg). Avaliou-se o rendimento do processo em termos de freqüências de resultados positivos e de contagens de ovos por lâmina de sedimento (0,078 ml). Ambos aumentaram com os valores de opg. As várias diluições não influíram nos graus de positividade ou nas contagens de ovos por lâmina de sedimento. Os sedimentos de suspensões fecais diluídas a 1,0% (quando o valor de opg era de 150,0). Em trabalho rotineiro é desnecessária a determinação instrumental das quantidades de fezes usadas nas suspensões. Diluições em torno de 1,0% representam um compromisso entre bom rendimento e limpidez dos esfregaços, especialmente quando os valores de opg forem baixos.

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.

[Evaluation of a technique of sedimentation in tubes]

The efficiency of sedimentation in test tubes for the detection of eggs of Ancylostomidae, Trichuris trichiura and Ascaris lumbricoides was tested in 80 mm-high columns of fecal suspensions. Dilutions of 2.0%, 1.5% and 1.0% were tested by using samples containing, respectively, 12.5, 25.0, 50.0, 100.0, 150.0 and 200.0 eggs per gram (epg) of each helminth under study. Efficiency was evaluated in terms of frequency of positive results and eggs per slide of the sediment (0.078 ml). Both the frequencies of positive results and egg counts per slide increased with epg values, but were not apparently dependent from suspension dilutions within the range assessed. Sediments of 1.0% fecal suspensions were positive in 80.0% or more of the cases for epg values of 150.0. It is inferred that dilution values are not critical. Thus, it is not necessary to determine fecal weights or volumes instrumentally. Considering overall results, it may be concluded that 1.0% fecal dilutions should be recommended for best results both in terms transparency of the preparations and chances of recovering eggs, particularly when egg counts are low.

Sistema de informação para a ação: subsídios para a atuação prática dos programas de saúde dos trabalhadores a nível local

Nas últimas décadas o Brasil transformou-se em uma sociedade industrializada. A partir da perspectiva epidemiológica e considerando as mudanças que estão ocorrendo a população brasileira, particularmente nos aspectos da transição demográfica, discute-se neste trabalho a necessidade de repensar a abrangência e prioridade do sistema de vigilância epidemiológica no país. O estudo avalia o sistema de informação para a ação de acidentes do trabalho a nível local, implantado no Programa de Saúde dos Trabalhadores do SUDS-R-6 (Mandaqui), tendo por base os dados de uma empresa metalúrgica da região que o sistema identificava como apresentando um processo de produção com alto risco de acidentes. A participação dos trabalhadores acidentados na discussão sobre os riscos ambientais e processo de trabalho, permitiu esclarecer a multicausalidade envolvida nos acidentes ocorridos nesta empresa. É destacada a importância da participação dos trabalhadores organizados - através de seus sindicatos, nas ações de controle dos acidentes. Embora, nem sempre essa participação organizada seja possível, o setor saúde deve buscar formas de atuação que resgatem a experiência concreta dos trabalhadores.

[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.

Avaliação de massas específicas de cistos de Giardia duodenalis e Entamoeba coli

Cistos de Giardia duodenalis e Entamoeba coli foram observados quanto à flutuação em soluções de sacarose de massas específicas diversas (1.040, 1.050, 1.060, 1.070,1.080,1.090,1.100, 1.150,1.200 e 1.250 kg/m³), contidas em câmaras de contagem de 0,17 mm de altura. Contaram-se os cistos que flutuaram e os que sedimentaram tendo sido calculadas as porcentagens respectivas. As diferenças de flutuabilidade dos cistos de cada uma das espécies não foram consideráveis. Soluções de massa específica igual a 1.200 kg/m³ fizeram flutuar 88,49% dos cistos de G. duodenalis e 95,71% dos de E. coli. Os maiores valores de flutuabilidade estiveram associados à massa específica 1.250 kg/m³ e foram, respectivamente, 89,15% e 98,59% para cistos de G. duodenalis e de E. coli.

[The evaluation of the specific gravity of Giardia duodenalis and Entamoeba coli cysts]

Cysts of Giardia duodenalis and Entamoeba coli were observed as for floatability in sucrose solutions of different specific gravity, contained in counting-chambers of 0.17 mm height. The cysts that floated and those that sedimented were counted and then calculated the respective percentage. Floatability differences of the cysts of each species were not considerable. Solutions of specific gravity 1,200 kg/m3 made 88.49% of G. duodenalis cysts and 95.71% of E. coli cysts float. The greater values of floatability were associated to specific gravity 1,250 kg/m3 and were 89.15% and 98.59% for cysts of G. duodenalis and E. coli, respectively.

Intestinal parasites among Karitiana Indians from Rondônia State, Brazil

Gravity sedimentation parasitological examinations were performed in stool samples from 111 Karitiana Indians from Rondônia State, Brazilian Amazon Basin. Intestinal parasites were found in 43 samples (38.7%). Ascaris lumbricoides was the most prevalent helminth species (18.9%). Egg counts in samples positive for Ascaris suggested an overdispersed distribution of worm burdens in the host population. Age-distribution pattern of intestinal parasites among Karitiana Indians was found to be rather unusual: the highest prevalence (60.0%) was detected in the 12- to 16-year-old age group.

Sedimentation in parasitological coproscopy

A sedimentation technique is described, in which a fecal suspension is placed on top of an aqueous sucrose solution of specific gravity 1.015 g/cm3. Using 100 by 15 mm test tubes, duplicate gravity sedimentation experiments were made using homogenized fecal suspensions (single-columns) and fecal suspensions placed on top of clear columns (double-columns). Egg and cyst counts, and turbidity determinations were made in the sediments obtained after definite time intervals. Most Ascaris lumbricoides, Trichuris trichiura and Ancylostomidae eggs sedimented within 20 minutes in single-and between 30 and 60 minutes in double-columns. Giardia duodenalis cysts required longer periods to sediment in double-than in single-columns; after 180 minutes (the maximum period of observation), double-column sediments produced 60.0% of the counts of single-columns. Double-column sediments were consistently less turbid than single-column ones.

Malaria seroepidemiology: comparison between indirect fluorescent antibody test and enzyme immunoassay using bloodspot eluates

Blood sampling on filter paper is a current practice in malaria seroepidemiological studies by indirect fluorescent antibody test (IFAT). There is, however, scant comparative information about the use of bloodspot eluates for detection of malarial IgG antibodies simultaneously by IFAT and enzyme immunoassay (ELISA). Here we report data obtained by both serological methods done on 219 bloodspot eluate samples collected in a rural community in Brazilian Amazon Basin (Alto Paraíso, Ariquemes municipality) where malaria is endemic. Plasmodium falciparum and P. vivax thick smear antigens were used in the IFAT; a detergent-soluble P. falciparum antigen was prepared for ELISA. Substantial agreement of results (Kappa coefficient k = 0.686) was observed when P. falciparum antigen was used in both tests, and IFAT titers were found to be strongly correlated to ELISA antibody units (Spearman correlation coefficient rs = 0.818, p < 0.001). Only moderate agreement (k = 0.467) between IFAT with P. vivax antigen and ELISA with P. falciparum antigen was observed. Spearman correlation coefficient value between quantitative results (IFAT titers and ELISA antibody units) in this case was numerically lower (rs = 0.540, p < 0.0001). Our results suggest that, with P. falciparum antigen, both IFAT and ELISA performed on bloodspot eluates are equivalent for seroepidemiological purposes.

Intestinal parasites in Iaualapiti Indians from Xingu Park, Mato Grosso, Brazil

Brine flotation and gravity sedimentation coproscopical examinations were performed in stool samples from 69 of the 147 Iaualapiti Indians of the Xingu Park, Mato Grosso State, Brazil. Intestinal parasites were present in 89.9% of the population examined. High rates of prevalence were found for some parasite species: Ancylostomidae, 82.6%; Enterobius vermicularis, 26.1%; Ascaris lumbricoides, 20.3%; and Entamoeba coli, 68.1%. Infection by Trichuris trichiura, Schistosoma mansoni, Taenia spp. and Hymenolepis nana was not detected. Helminth's prevalence in children aged one year or less was comparatively low (33.3%). Quantitative coproscopy was done in positive samples for Ascaris and Ancylostomidae and the results expressed in eggs per gram of feces (EPG). Quantitative results revealed that worm burdens are very low and overdispersed in this Indian tribe, a previously unreported fact.

Prevalência e intensidade de infecção por Ascaris lumbricoides em amostra populacional urbana (São Paulo, SP)

Pesquisaram-se ovos de Ascaris lumbricoides em amostras fecais de 407 moradores (8,87% do total) de uma favela da cidade de São Paulo. Realizaram-se exames qualitativos (sedimentação por gravidade) e quantitativos (técnica de Kato & Miura adaptada a contagens). Discutem-se aspectos diferenciais da epidemiologia da ascaríase em áreas urbanas e rurais, com base em dados deste estudo e da literatura. Salienta-se a importância, em epidemiologia, da quantificação de exames de fezes.

[Method of Faust et al.: yield of collection through metallic loop]

The efficiency of the use of a wire loop for the removal of floating parasitic elements was investigated. The quantity of elements removed by each successive loopful was confronted with a logarithmic model which indicated that each loopful carried about 30% of the remaining floating parasitic elements. It was estimated that the first five loopfuls carried a total of 83% of the floating parasitic elements, being this adequate procedure for the method under investigation.