The incidence of Shiga toxin-producing Escherichia coli in cattle with mastitis in Brazil

Aims: To determine the prevalence and molecular characteristics of Shiga toxin-producing Escherichia coli (STEC) isolates from bovine mastitic milk in Brazil.Methods and Results: A total of 2144 milk samples from dairy cattle showing mastitis were screened for the presence of E. coli. A total of 182 E. coli isolates were selected and examined. All were subjected to dot blot analysis using the CVD419 probe for the detection of the enterohaemolysin (hly) gene, and to a multiplex PCR for the detection of stx1, stx2 and eaeA genes. STEC were isolated from 22 (12.08%) milk samples. All the STEC isolates were tested for sensibility to 10 antimicrobials; the resistances most commonly observed were to cephalothin (86.3%), tetracycline (63.6%) and doxycycline (63.6%).Conclusion: STEC isolates were found in bovine mastitic milk in Brazil.Significance and Impact of the Study: STEC isolates from mastitic milk were potentially pathogenic for human in that they belonged to serogroups associated with diarrhoea and haemolytic-uraemic syndrome, some of them were stx2, eaeA and hly positive.

SEASONAL SPACE USAGE BY THE INTRODUCED PHARAOHS ANT, MONOMORIUM-PHARAONIS (L) (HYM, FORMICIDAE), IN INSTITUTIONAL SETTINGS IN BRAZIL AND ITS RELATION TO OTHER STRUCTURAL ANT SPECIES

In an institutional setting in Brazil, the pharaoh's ant, Monomorium pharaonis was found to be the dominant and most abundant ant present throughout the year. The only other regularly collected ant was the exotic Tapinoma melanocephalum. However, M. pharaonis dominated bait station visitations, although locally concentrated, with other species restricted to regions in which M. pharaonis was not found.

Circadian and seasonal variation in the essential oil from Virola surinamensis leaves

The essential oil from leaves of Virola surinamensis shows circadian variation in elemicin and in monoterpenes during the rainy season (February). The monoterpenes represents 50% of total volatile compounds during the dry season(June). Sesquiterpenes are predominant (50%) in the early rainy season (October). (C) 1997 Published by Elsevier B.V. Ltd.

Radionuclides, heavy metals and fluorine incidence at Tapira phosphate rocks, Brazil, and their industrial (by) products

Inorganic phosphate fertilizers may contain radionuclides, heavy metals and fluorine. This paper presents the possible environmental hazards from Tapira phosphate rocks and their (by) products (Brazil) utilized as phosphate fertilizers. The activity concentration of U-238, U-234, Ra-226 and K-40 in Tapira phosphate rocks is within the world range for these rock types. The Th-232 activity concentration is higher than the mean reported in phosphate rocks. A value of 2184 nGy h(-1) was obtained for the exposure dose rate in Tapira phosphate deposit area, which is indicative of a high background radiation area. The flotation-separation process causes the incorporation of no more than 9%, 11 % and 24% of radionuclides, heavy metals and fluorine, respectively, into the phosphate concentrate. The radionuclides and heavy metals existing in phosphate fertilizers applied in Brazilian crops according to the recommended rates, do not raise their concentration in soils to harmful levels. (C) 2005 Elsevier Ltd. All rights reserved.

Grazing incidence X-ray diffraction and atomic force microscopy analysis of BaBi2Ta2O9 thin films

Thin films of BaBi2Ta2O9 (BBT) composition were prepared through the metal organic decomposition method. The crystallinity, phase formation, crystallite size and morphology of the thin films were measured as a function of the type of substrate, stoichiometry of solution and process variables such as thickness and temperature. The thin films were investigated by grazing incidence X-ray diffractometry and atomic force microscopy (AFM) techniques. For the sample without excess of bismuth, diffraction peaks other than that of the BBT phase were observed. A well crystallized BBT single phase was observed for films prepared from a solution with 10% excess of bismuth, deposited on Si/Pt substrate, with a thickness up to 150 nm and sintered at temperatures of 700 degreesC. The thin BBT phase films heat-treated at 600 degreesC presented a diffraction pattern characteristic of samples with lower degree of crystallinity whereas for the thin films heat-treated at 800 degreesC, we observed the presence of other phases than the BBT. For the thin film deposited on the Sin+ substrate, we observe that the peaks corresponding to the BBT phase are broader than that observed on the samples deposited on the Pt and Si/Pt substrates. No variation of average crystallite size was observed as the excess of Bi increased from 10 to 20%. AFM images for the samples showed that the increasing the amount of bismuth promotes grain growth. The average surface roughness measured was in the range of 16-22 nm showing that the bismuth amount had no or little effect on the roughness of films. (C) 2002 Elsevier B.V. B.V. All rights reserved.

DISTRIBUTION AND SEASONAL DYNAMICS OF RHODOPHYTA IN THE PRETO RIVER BASIN, SOUTHEASTERN BRAZIL

Distribution and seasonal dynamics of freshwater Rhodophyta were investigated in the Preto River basin, located in northwestern São Paulo State, southeastern Brazil. Twenty-two sites were sampled, six monthly during one year, four bimonthly during two years, and 12 twice (hot-rainy and cool-dry seasons) during the study period (May 1989 through March 1991). Red algal representatives were found in 19 sites (86.4%). Four species occurred in the basin with varying frequencies: Batrachospermum delicatulum (54.5%), Compsopogon coeruleus (36.4%), B. bicudoi (13.6%) and B. virgatum (4.5%). In addition, 'Chantransia' stage of the batrachospermalean species was found in 17 sites (77.3%). B. bicudoi, B. virgatum and C. coeruleus occurred only in large stream segments (greater-than-or-equal-to 3-order), generally in the main river, whereas B. delicatulum was more frequent in small streams (less-than-or-equal-to 3-order). The stream variables most closely related to the species distribution in the basin were specific conductance, pH and oxygen. B. bicudoi and B. delicatulum showed a marked seasonality: gametophytes were observed from late fall to early spring, while the 'Chantransia' stage generally occurred throughout the year. C. coeruleus was observed throughout the year in most sites, but the populations were generally more abundant from late fall to early spring. The combination of lower temperature and reduced turbidity resulting in increased illumination to the benthic algae during the dry winter months promotes the gametophytic growth of the batrachospermalean species, whereas current velocity was found to be the most influential stream variable for C. coeruleus. The persistance of the 'Chantransia' stage throughout the year as well as its tolerance to wider environmental conditions are key factors in the efficiency of the batrachospermalean life history strategy in lotic ecosystems.

Reproductive biology and seasonal distribution of Mustelus schmitti (Elasmobranchii : Triakidae) in the Rio de la Plata oceanic front, south-western Atlantic

The population structure and reproductive biology of Mustelus schmitti was analysed during autumn (1994, 1995) and spring (1994) in the Rio dc la Plata occanic front. The samples consisted mainly of a adult males and immature females, indicating that nursery areas are Situated elsewhere. In autumn, the highest female densities occurred between 36 degrees S and 35 degrees S, with densities decreasing further south, and high male densities occurred over all latitudes of the study area. In Spring, both Sexes occurred north of latitude 36 degrees 30 degrees S. Males attained Maturity at. 59 cm total length (TL), and females at 72 cmTL Litter size varied From one to ten in spring and two to nine in autumn, With embryos ranging from 9 to 26 cm and 7 to 26 cm TL respcctivcly the mean TL of embryos was significantly higher in spring (22 cm), suggesting that parturition Occurs ill late spring and summer. Litter size was found to Increase with female TL..

INCIDENCE OF MYCOBACTERIUM-TUBERCULOSIS AND OTHER MYCOBACTERIA ON PULMONARY INFECTIONS IN ARARAQUARA - SP, 1993

The incidence of tuberculosis and other infections by mycobacteria was analyzed in 559 patients admitted to the Tisiology Section of the Special Health Care Unit of Araraquara (SESA). Mycobacteria were isolated from 78 individuals out of this total. Among these patients, 15 were also HIV positive. The occurrence of isolated species was: M. tuberculosis: 69 patients; M. avium-intracellulare: 5 patients; M. fortuitum: 2 patients; M. chelonae: 1 patient; and M. simiae 1 patient. The latter was for the first time isolated from humans in Brazil. In most cases, non tubercular mycobacteria (NTM) were found in the HIV positive patients.

SEASONAL DYNAMICS OF MACROALGAL COMMUNITIES IN THE PRETO RIVER BASIN, SAO-PAULO, SOUTHEASTERN BRAZIL

Macroalgal seasonality was analyzed in nine stream segments of the Preto River basin: five of these were sampled monthly for one year and four bimonthly during two years. Seasonal variation of macroalgae was correlated with stream variables (temperature, current velocity, specific conductance, turbidity, surface light, pH and oxygen). Multiple linear regression was applied to evaluate the macroalgal seasonal variability determined by a combination of temperature, current velocity and turbidity, the most influential environmental parameters on macroalgal seasonality. Most species revealed a clear seasonal trend, such that late fall through early spring was the period with highest macroalgal abundance in most sites. Temperature, current velocity and turbidity account for 24 to 83 % of macroalgal species number variation and 24 to 79 % of macroalgal abundance in the basin. The results suggest that the seasonal flow determined by the precipitation regime associated with turbidity and temperature were the major factors influencing the seasonal dynamics of macroalgal communities. The highest values of macroalgal species number and abundance were found under cooler temperatures, lower current velocities and lower values of turbidity.

POPULATION-BASED INCIDENCE OF IDDM IN THE STATE OF SAO-PAULO, BRAZIL

OBJECTIVE- To study the incidence of IDDM among children, infants to 14 yr of age, in the state of São Paulo, Brazil, 1987-1991.RESEARCH DESIGN AND METHODS - A prospective population-based register was established, using physician reports of newly diagnosed IDDM patients < 15 yr of age as the primary source of case identification and school surveys as the main secondary source. Data were collected according to the methods recommended by the Diabetes Epidemiology Research International group.RESULTS - Case ascertainment was estimated at 95.0, 92.8, and 98.8% complete for each of the three cities studied. The average annual IDDM incidence was 7.6/100,000 inhabitants (95% confidence interval, 5.6-9.7). We found a higher incidence rate in girls than boys.CONCLUSIONS - the incidence of childhood IDDM in a tropical region in South America (São Paulo, Brazil) is in the middle incidence range observed in developed countries throughout the world. Increased incidence of IDDM in girls compared with boys will be tested by the ongoing Brazilian incidence study being developed in 18 other centers across the country.

Methane and carbon dioxide seasonal cycles at urban Brazilian inland sites

Methane and carbon dioxide seasonal cycles during years 1998 and 1999 at two Brazilian urban and inland sites are presented. The mixing ratio averages over the studied period of time were 1.80 ppm CH4 and 384.7 ppm CO2. A comparison is made between continental averages and the averages of the three nearest global network background sites of NOAA-CMDL comprising Ascension Island, Namibia and Easter Island. Inland sites had 0.08 ppm or 4.9% more CH4 and 19.0 ppm or 4.9% more CO2 than background over the same time span. The CH4 summer minimum observed in remote sites was also detected inland. During the month of October 98 and 99 inland mixing ratios were frequently similar to background.