Asymptomatic carriers of Plasmodium spp. as infection source for malaria vector mosquitoes in the Brazilian Amazon

We have described the existence of asymptomatic carriers of Plasmodium vivax and Plasmodium falciparum infections in native Amazon populations. Most of them had low parasitemias, detected only by polymerase chain reaction (PCR). Because they remain symptomless and untreated, we wanted to determine whether they could infect Anopheles darlingi Root, the main Brazilian vector, and act as disease reservoirs. Fifteen adult asymptomatic patients (PCR positive only) were selected, and experimental infections of mosquitoes were performed by direct feeding and by a membrane-feeding system. Seventeen adult symptomatic patients with high parasitemias were used as controls. We found an infection rate in An. darlingi of 1.2% for the asymptomatic carriers and 22% for the symptomatic carriers. Although the asymptomatic group infected mosquitoes at a much lower rate, these patients remain infective longer than treated, symptomatic patients. Also, the prevalence of asymptomatic infections is 4 to 5 times higher than symptomatic infections among natives. These results have implications for the malaria control program in Brazil, which focuses essentially on the treatment of symptomatic patients. © 2005 Entomological Society of America.

Comparative field test between two sugar cane (Saccharum spp.) harvesters under two different operational conditions in Brazil

The sugar cane crop is one of the main products in Brazil and according to several authors can generate, besides the industrialized stalks, an amount of crop residues from the order of 15 to 30 % in weight of the aerial part of the plants, depending on the field conditions. The sugar cane area in Brazil is around 5.5×106 hectares, with an amount of 400.106 tons of stalks, with stalks yield of 72 tons.ha-1. This study took place in a sugar cane plot (Latitude 22°46'S, Longitude 47°23'W and 600m of altitude) with 3% of slope, located in São Paulo State. The sugar cane variety was SP 80-1816, in its forth cut, 11 months old and with a planted row spacing of 1.40 m. By other side, several sugar mills are bringing the crop residue to their patio to produce energy with the bagasse. One choice is to bring the crop residue at the same moment with the stalks, avoiding the next operation of baling it. The objective of this study was to analyze some operational parameters of two different sugar cane harvesters under the same field conditions, which was divided in four treatments: T1 = CAMECO CHT2500B operating normally; T2 = CAMECO CHT2500B operating without the cleaning system; T3 = CASE 7700 operating normally; T4 = CASE 7700 operating without the cleaning system. The results obtained were: Table presented CEB = Gross effective capacity; CEL = Net effective capacity. The conclusion is that under normal operation the CASE harvester worked better then CAMECO in the parameters CEL stalks and Manipulation efficiency. And without the cleaning system operating CASE also worked better in the parameters of CEB raw material, CEB stalks, CEL raw material and CEL stalks.

Sugar cane (Saccharum spp.) crop residue baling for energy purposes in Brazil

The sugar cane crop according to several authors can generate, besides the industrialized stalks, an amount of crop residues from the order of 15 to 30% in weight of the aerial part of the plants, depending on the field conditions. The sugar cane area in Brazil is around 5.5×106 hectares, with an amount of 400.106 tons of stalks, with stalks yield of 72 tons.ha-1 (Unica, 2005). This study took place in a sugar cane plot (Latitude 22°46'S, Longitude 47°23'W and 600m of altitude) with 3% of slope, located in São Paulo State. The sugar cane variety was SP 80-1816, in its forth cut, 11 months old and with a planted row spacing of 1.40m. By other side, several sugar mills are bringing the crop residue to their patio to produce energy with the bagasse. One way for that is the baling operation to bring the crop residue at the sugar mill. Some fundamental variables were obtained to define the best set of machines to work with in sugar cane crop residue removal in the baling system among the studied ones, some of the variables were: Soil Index (T1 = 0.83%, T2 = 0.46%, T3 = 0.65%, T4 = 0.57%); Energy Efficiency (T1 = 82.48%, T2 = 83.88%, T3 = 82.83% and T4 = 82.97%) of the system and Effective Cost for Equivalent Energy in US$.EBP-1 (T1 = 11.10, T2= 10.46, T3 = 11.47 and T4 = 10.57) of the baled trash delivered at the sugar mill.

Analysis of susceptibility profile of Pseudomonas spp. and prevalence of bacterial samples from the surfaces of dental consulting-rooms

The aim of this research was to evaluate the susceptibility profile of Pseudomonas spp. and the prevalence of bacterial samples isolated from horizontal surfaces surrounding wash-basins used by dentists in several adjoined consulting-rooms, at points next to and at a distance from the basin, before and after surgical procedures. Our results showed a high percentage of Gram-positive cocci and Gram-negative bacilli; 34.66% were Staphylococcus spp. and 30.12% were non-fermentative Gram-negative bacilli among which Pseudomonas spp. (40.90%) was the commonest genus. Analysis of the susceptibility profile of Pseudomonas spp. isolates by determining the minimal inhibitory concentration (MIC) of 14 antibiotics showed a great variation among the strains and high rates of resistance to cefazolin, ceftazidime and aztreonan. Of the 14 antibiotics tested, 59.03% were found to be active against all the environmental isolates. Strains were resistant to aztreonan (62.82%), while susceptibility to third generation cephalosporins was variable.

Genetic divergence in Eucalyptus spp. clones by molecular RAPD markers

The genetic divergence in 20 Eucalyptus spp. clones was evaluated by multivariate techniques based on 167 RAPD markers, of which 155 were polymorphic and 12 monomorphic. The measures of genetic distances were obtained by the arithmetic complement of the coefficients of Jaccard and of Sorenso-Nei and Li and evaluated by the hierarchical methods of Single Linkage clustering and Unweighted Pair Group Method with Arithmetic Mean (UPGMA). Independent of the dissimilarity coefficient, the greatest divergence was found between clones 7 and 17 and the smallest between the clones 11 and 14. Clone clustering was little influenced by the applied procedure so that, adopting the same percentage of divergence, the UPGMA identified two groups less for the coefficient of Sorenso-Nei and Li. The clones evidenced considerable genetic divergence, which is partly associated to the origin of the study material. The clusters formed by the UPGMA clustering algorithm associated to the arithmetic complement of Jaccard were most consistent.

Avaliação de fatores de risco de cães sororreagentes à leptospira spp. e sua distribuição espacial, em área territorial urbana

We aimed to evaluate the risk factor of serum reactive dogs to antileptospire agglutinin and their spatial distribution in an urban area. We collected 1,000 blood samples from dogs at 20 immunization centers, homogeneously distributed in the urban area (32 km²) of Botucatu, Sao Paulo, Brazil. Diagnosis was made by microscopic serum agglutination using 24 serovars of Leptospira spp. Statistical analysis was performed by Goodman's test with 5% of significance. Spatial clusters were tested by spatial scan statistic using SaTScan. We found that 17.9% dogs reacted to Leptospira spp. (p<0.0001). Dogs with street access (22.14%) were more reactive (p<0.05) than those without (14.83%). The scan test indicated only one significant cluster influenced by age. Incorporating each one of the co-variables gender, breed, and street access to age, we found that street access was the most important. Street access and age were the most important risk factors in the large number of reactive animals in the cluster, with the castellonis serovar being the most reactive in urban dogs. The identification of a cluster with more reactive dogs than expected allows local preventive measures to be taken.

Presence of Candida spp. in infants oral cavity and its association with early childhood caries

Candida spp., mainly C. albicans, colonizes oral cavity of infants. Transmission by mother to childbirth, pacifier use, feeding habits and caries are factors related to Candida oral colonization. Some researches related that early childhood caries favor the oral colonization of C. albicans. The present literature review described the presence of Candida spp. in oral cavity of infants and its association with early childhood caries (ECC). The literature was searched for original papers relating Candida, pacifier and baby bottle usage and ECC.The articles, were selected using Bireme and Medline databases. Manual tracing of references cited in key papers was also elicited It can be concluded that Candida spp. colonization in the infants'oral cavity especially C. albicans, can be related to the pacifier usage, feeding habits caries lesion. The early childhood caries favor the C. albicans colonization, although it's role in the carious process need further studies to be elucidate scientifically.

Research on staphylococcus spp in biofilm formations in water pipes and sinsibility to antibiotics

Water from dental equipment presents risks for surgeon-dentists as well as for patients because it might work as a means of dissemination/ transmission of microoganisms. The objective of this study was to verify the quality of the water used in dental equipment by means of microbiological analysis, accomplishing the count of Staphylococcus spp.There have been collected, 160 samples of water from reserviors, taps used for hand washing, air-water syringes, and high-speed handpieces, in 40 dental offices in the city of Barretos, São Paulo. The rules concerning bacteriotogicaI analysis in cfu/mL from Standard Methods for the Examination of Water and Wastewater have been followed. The analysis of the results has made it possible to verify that out of the total of samples, 28% did not meet the standards of potability established by the American Dental Association: Regarding the origin of analyzed S. aureus., the most contaminated sites were high-speed handpicces in private offices (761%) and in, ental care plan offices (71%), followed by air-water syringe in dental care plan offices (64%). For S. epidermitis samples, the most contaminated sites were high-speed handpieces in SUS (Brazilian Government Health System) dental offices (22%) and in dental care plan offices (14%) The most contaminated sites were dental offices that saw Patients under dental care plans, Concerning tested antibiotics, the ones that presented better results as to sensibility to strain S. epidermidis were vancomycin and ciprofloxacin (100%) and, as to sensibility to strain S. aureus, it was ciprofloxacin (97%).

Comparative study of disk diffusion and microdilution methods for evaluation of antifungal activity of natural compounds against medical yeasts Candida spp and Cryptococcus sp

Antifungal activity of natural products has been tested by adapting methods designed for synthetic drugs. In this study, two methods for the determination of antifungal activity of natural products, agar diffusion and broth microdilution, the CLSI reference methods for synthetic drugs, are compared and discussed. The microdilution method was more sensitive. The minimal inhibitory concentrations (MIC) of crude extracts, fractions and pure substances from different species of the plant families Piperaceae, Rubiaceae, Clusiaceae, Fabaceae and Lauraceae, from the Biota project, were determined. Antifungal activities against Candida albicans, C.krusei, C.parapsilosis and Cryptococcus neoformans were produced by several samples.

Efeito da aplicação de maturadores químicos na cultura da cana de açúcar (Saccharum spp.) variedade SP81-3250

Sugarcane is one of the most important grass crops. This study evaluated the effects of chemical ripeners on the sugarcane variety SP81-3250 in terms of technological quality. The experiment was arranged in randomized blocks with split split-plots. Main treatments were: 1) Control; 2) Aminolon Maduracion, at a rate of 0.7 L of commercial product (c.p.) ha -1; 3) Aminolon Maduracion, at a rate of 1.0 liter of c.p. ha -1; 4) Aminolon Maduracion, at a rate of 1.3 liter of c.p. ha -1; 5) Trinexapac-ethyl (Moddus), at a rate of 0.8 liter of c.p. ha -1. Secondary treatments were the sampling dates: 10 days before application (- 10 d.a.a.); 11; 46; 71; 100 and 117 d.a.a. (days after application). Ripeners differently affected the technological parameters, and trinexapac-ethyl showed the best behavior, followed by Aminolon (0.7 L of c.p. ha -1). The best results were found at the 3rd and 4th sampling dates, 46 and 71 days after application, respectively.

Phenotypic characterization of Candida spp. isolates from chronic periodontitis patients

Aim: Several typing methods for Candida spp. have been suggested in the literature in order to distinguish isolates for studies about the virulence or infection routes of these microorganisms and, in particular, for epidemiological purposes. The aim of this study was to establish a comparison between the phenotypic profile of oral Candida isolates from periodontitis patients and control individuals. Methods: The morphotyping and biotyping of 35 C. albicans isolates obtained from chronic periodontitis patients and 48 isolates from control individuals were performed. For morphotyping, the isolates were plated on malt extract agar and incubated for 10 days. Sixteen different morphotypes were observed for C. albicans, the most frequently observed being 0000 and 0001. Results: Biotype 0000 (complete absence of fringe) was most prevalent among the isolates obtained from periodontitis patients compared to those from control individuals, with statistical significance. Biotyping revealed 5 different biotypes with higher prevalence of the biotype 357 among the isolates from control and periodontitis groups. Conclusions: The results obtained by biotyping of the isolates did not permit to differentiate a characteristic model related to periodontal disease, whilst the morphotype 0000 was most frequently isolated from periodontitis patients.

Avaliação da reatividade cruzada entre antígenos de Leishmania spp e Trypanosoma cruzi na resposta sorológica de cães pela técnica de imunofluorescência indireta (RIFI)

Visceral Leishmaniasis (VL) is a zoonosis caused by Leishmania spp. protozoa. Dog is the main parasite's reservoir, especially in urban areas. Indirect Immunofluorescent Antibody Test (IFAT) is commonly used for canine visceral leishmaniasis (CVL) diagnosis, by detection of antibodies against the parasite. However, Trypanosoma cruzi (T.cruzi) cross reactions can occur in serological diagnosis. In order to evaluate the occurrence of cross reactions between antigens of Leishmania spp. and T.cruzi, 150 blood samples of CVL epidemiological inquiry positive dogs were collected and sera were tested by IFAT. Dogs were culled at Zoonosis Control Center of Bauru (SP), an endemic area for VL. Another 150 dogs' blood samples were collected in Botucatu (SP), a non endemic area for LV, and sera were also tested by IFAT. Serum samples of dogs from Bauru were positive, both for Leishmania spp. and for T. cruzi, showing high cross-reactions incidence, reinforcing the need of diagnosis confirmation by other tests. Serum samples of dogs from Botucatu demonstrated low prevalence of positive results by IFAT, both for Leishmania spp. and T.cruzi. However, despite the low number of positive serological results for these parasites, the epidemiological and serological investigation for LV and Chagas disease in dogs from Botucatu must be kept, considering the importance of dog as domestic reservoir for both parasites.

Detecção de Escherichia coli e Salmonella spp. em microbiota intestinal de Psittaciformes em fase de reabilitação para soltura

Escherichia coli is a bacteria of the Enterobacteriacea family and it is part of the enterical microflora of mammals and of many species of birds. Salmonella spp. also belongs to the family Enterobacteriacea, it is responsible for human feed toxinfection outbreaks and usually isolated from domestic and wild birds. The present study analyzed the frequency of both agents in Psittaciformes in rehabilitation process for wildlife reintroduction. In 89 birds analyzed, 19% were infected with E. coli and 1,12% with Salmonella spp. It was carried out an analysis of the profile of antibiotic resistance in which was observed the efficiency of estreptomicin, tetraciclin, trimetoprim and gentamicin over the samples. The samples of E. coli were submitted to the Congo Red Binding test and to the Hemolisis test and 70,6% of positive samples for the first test and 53% for the second one were observed.

Anticorpos anti-Leptospira spp. em animais selvagens do zoológico municipal de Ribeirão Preto, Estado de São Paulo, Brasil

Leptospirosis may affect all domestic and wild animals as well as human beings. Some serological studies have shown the involvement of wild species in the epidemiology of the disease. Once captive wild animals are not much studied, especially in Brazil, the present study aimed to detect anti- Leptospira spp. antibodies in animals from Ribeirão Preto city zoo, in São Paulo state, Brazil. Blood samples were collected from captive birds, fish, reptiles and mammals, sinanthropics and free-living animals and also from employees between March and October, 2006. Four hundred and three blood samples were obtained, 388 animals' samples (110 reptiles, 143 birds, 110 mammals and 25 fish) and 15 humans'. The sera were analysed by Microscopic Agglutination Test using 22 serovars from pathological leptospiras and two from non-pathological serovars. Among the animal samples, 339 were from captive animals, and 49 from free-living ones, captured with traps inside the zoo. One hundred and three (103/388 = 26.5%) samples reacted to leptospirosis, ninety-two (92/339 = 27.1%) samples were from captive animals and eleven (11/49 = 22.4%) from free-living ones. All humans' samples were negative. Serological titles varied from 40 to 5.120, with predominance of titles between 40 and 80 and the most frequent serovars were Patoc, Andamana, Canicola, Icterohaemorrhagiae and Panama.

Distribuição e abundância de larvas de Simulium spp.em córregos do estado de São Paulo nos diferentes níveis de qualidade da água

The aim of this work was to determine the distribution and abundance the species of Simulium: in 5 streams of the north coastal region of the state of São Paulo. Simulium larval and water samples were collected every 2 weeks in summer and winter, 2001. The larval were collected on artificial substrates (triplicate) preserved in alcohol (70%) and after analyzed quantitative and qualitative. From the streams the values of temperature, dissolved oxygen, conductivity, pH and stream discharge were measured. The contents of total nitrogen and dissolved nitrogen, ammoniacal nitrogen, nitrate, nitrite, orthophosphate, dissolved phosphorus and total phosphorus were determined in the laboratory. Water quality has great influence in the distribution and abundance of the species. S. pertinax was more abundant in streams without or with low levels of pollution, S. inaequale in streams more polluted and S. incrustatum in intermediary levels of pollution. S. pertinax was the species more abundant with 57.5% of presence in the samples, the second more abundant was S. inaequale with 42.1% of presence and S. incrustatum was rare with 0.4% of presence. The larval abundance was lower in the polluted environment. © 2012 by Unisinos.