Compared nymphal development of Tingis americana (Hemiptera, Tingidae) in two Handroanthus species (Bignoniaceae) and reproductive parameters in seedlings of Handroanthus heptaphyllus

Nymphs and adults of Tingis americana Drake, 1922 were found feeding on leaves of Handroanthus heptaphyllus (Vell.) Mattos and Handroanthus chrysotrichus (Mart. ex A. DC.) Mattos in the Botanic Garden, Porto Alegre, state of Rio Grande do Sul, Brazil. This is the first record of T. americana on these host plants and in the southern Brazil. We aimed to compare the nymphal development on both hosts and to analyze the reproductive parameters on H. heptaphyllus (25 ± 1ºC; 60 ± 10% RH; 16 h photophase). The mean nymphal period (days) was shorter in individuals reared on H. heptaphyllus (12.69 ± 0.076) than on H. chrysotrichus (19.11 ± 0.208) (P < 0.0001), however, nymph viability was similar. On H. heptaphyllus, the mean embryonic period lasted 12.32 ± 0.274 days and the egg viability was 92%. The mean total and daily fecundity were 310.0 ± 19.40 eggs/female and 7.46 ± 0.302 eggs/female/day, respectively. Paired males and females showed similar longevity (P = 0.0691), while unpaired females lived longer than unpaired males (P = 0.0460).

Genetic and Antigenic Analysis of Adenovirus Type 3 Strains Showing Intermediate Behavior in Standard Seroneutralization Test

During an epidemiological survey of acute respiratory infection in Rio de Janeiro, among 208 adenovirus isolates, we found two strains that we were not able, by a standard neutralization procedure, to distinguish between type 3 or 7. However, DNA restriction pattern for the two strains with different enzymes were analyzed and showed a typical Ad3h profile. Using a cross-neutralization test in which both Ad3p and Ad7p antisera were used in different concentration against 100 TCID50 of each adenovirus standard and both isolates, we were able to confirm that the two isolates belong to serotype 3. An hemagglutination inhibition test also corroborated the identification of both strains as adenovirus type 3. Comparing Ad3h and Ad3p genome, we observed 16 different restriction enzyme sites, three of which were located in genomic regions encoding polypeptides involved in neutralization sites

Hepatitis C among former athletes: association with the use of injectable stimulants in the past

This study was performed with the purpose of testing the hypothesis that the high prevalence of hepatitis C among former athletes is associated with their past use of injectable stimulants. The study involved the participation of 208 former professional and amateur soccer and basketball players from the region of Ribeirão Preto, Brazil, who answered a questionnaire regarding their exposure to risk factors, including the use of injectable stimulants in the time they were engaged in sporting activities. ELISA tests were used to detect infection by the hepatitis C virus, and confirmed with PCR and genotyping for the positive cases. It was observed that the former use of injectable stimulants was a practice disseminated among the participants (24.5%), reaching 50.8% in the professionals. The overall prevalence for hepatitis C was 7.2%, with values of 11% among professionals and 5.5% among amateurs. In both categories, the presence of infection was markedly higher among those who admitted past use of injectable stimulants when compared to those who denied such practice (36% and 0.8% among amateurs; 21.9% and 0% among professionals, respectively). Multivariate analysis showed that the use of those substances was the only variable associated with the risk of hepatitis C. This confirms previous observations, performed with reduced sample sizes and without comparison groups, which indicated that the use of injectable vitamins was a risk factor of hepatitis C among former athletes.

Evaluation of rapid techniques for the detection of mycobacteria in sputum with scanty bacilli or clinically evident, smear negative cases of pulmonary and extra-pulmonary tuberculosis

The objective of the current study was to compare two rapid methods, the BBL Mycobacteria Growth Indicator Tube (MGIT TM) and Biotec FASTPlaque TB TM (FPTB) assays, with the conventional Löwenstein-Jensen (LJ) media assay to diagnose mycobacterial infections from paucibacillary clinical specimens. For evaluation of the clinical utility of the BBL MGIT TM and FPTB assays, respiratory tract specimens (n = 208), with scanty bacilli or clinically evident, smear negative cases and non-respiratory tract specimens (n = 119) were analyzed and the performance of each assay was compared with LJ media. MGIT and FPTB demonstrated a greater sensitivity (95.92% and 87.68%), specificity (94.59% and 98.78%), positive predictive value (94.91% and 99.16%) and negative predictive value (96.56% and 90.92%), respectively, compared to LJ culture for both respiratory tract and non-respiratory tract specimens. However, the FPTB assay was unable to detect nontuberculous mycobacteria and few Mycobacterium tuberculosis complex cases from paucibacillary clinical specimens. It is likely that the analytical sensitivity of FPTB is moderately low and may not be useful for the direct detection of tuberculosis in paucibacillary specimens. The current study concluded that MGIT was a dependable, highly efficient system for recovery of M. tuberculosis complexes and nontuberculous mycobacteria from both respiratory and non-respiratory tract specimens in combination with LJ media.

Examining ERBB2 as a candidate gene for susceptibility to leprosy (Hansen’s disease) in Brazil

Leprosy remains prevalent in Brazil. ErbB2 is a receptor for leprosy bacilli entering Schwann cells, which mediates Mycobacterium leprae-induced demyelination and the ERBB2 gene lies within a leprosy susceptibility locus on chromosome 17q11-q21. To determine whether polymorphisms at the ERBB2 locus contribute to this linkage peak, three haplotype tagging single nucleotide polymorphisms (tag-SNPs) (rs2517956, rs2952156, rs1058808) were genotyped in 72 families (208 cases; 372 individuals) from the state of Pará (PA). All three tag-SNPs were associated with leprosy per se [best SNP rs2517959 odds ratio (OR) = 2.22; 95% confidence interval (CI) 1.37-3.59; p = 0.001]. Lepromatous (LL) (OR = 3.25; 95% CI 1.37-7.70; p = 0.007) and tuberculoid (TT) (OR = 1.79; 95% CI 1.04-3.05; p = 0.034) leprosy both contributed to the association, which is consistent with the previous linkage to chromosome 17q11-q21 in the population from PA and supports the functional role of ErbB2 in disease pathogenesis. To attempt to replicate these findings, six SNPs (rs2517955, rs2517956, rs1810132, rs2952156, rs1801200, rs1058808) were genotyped in a population-based sample of 570 leprosy cases and 370 controls from the state of Rio Grande do Norte (RN) and the results were analysed using logistic regression analysis. However, none of the associations were replicated in the RN sample, whether analysed for leprosy per se, LL leprosy, TT leprosy, erythema nodosum leprosum or reversal reaction conditions. The role of polymorphisms at ERBB2 in controlling susceptibility to leprosy in Brazil therefore remains unclear.

Acúmulo de ácido oxálico e cristais de cálcio em ectomicorrizas de eucalipto.: I- produção de ácido oxálico e concentração de nutrientes em raízes laterais finas colonizadas por fungos ectomicorrízicos

O eucalipto apresenta ótimo crescimento em solo com baixa fertilidade, mas pouco se sabe sobre a participação das ectomicorrizas e de ácidos orgânicos na aquisição e no acúmulo de nutrientes pela planta em campo. A produção de ácido oxálico e sua relação com as concentrações de P, Ca, Mg e K foram avaliadas em ectomicorrizas e raízes laterais finas de híbrido de Eucalyptus grandis x Eucalyptus urophylla, de 2,5 anos de idade, na região de Viçosa, MG. A área de estudo apresenta topografia típica em meia laranja, de vertente côncavo-convexa. Foram também avaliadas as concentrações desse composto no solo rizosférico, não rizosférico e ectomicorrizosférico. As maiores percentagens de colonização micorrízica foram observadas na área de encosta, onde havia limitada disponibilidade de nutrientes e alta saturação de Al. As concentrações de ácido oxálico + oxalato corresponderam, em mg kg-1: folhas, 324,6; ectomicorrizas, 208,3; raízes laterais finas não colonizadas, 183,1. Já no solo, as concentrações foram maiores no solo ectomicorrizosférico, com 183,7 mg kg-1, seguido pelo solo rizosférico, com 134,3 mg kg-1, e pelo solo não rizosférico, com 76,0 mg kg-1. As maiores concentrações de ácido oxálico e P (p < 0,05) nas ectomicorrizas da área do topo, 117,3 mg kg-1 e 6,3 g kg-1, respectivamente, sugerem que as populações de fungos ectomicorrízicos nesta área têm papel importante na solubilização e disponibilização de nutrientes para o hospedeiro. Não foram observadas correlações positivas significativas entre a produção de ácido oxálico e as concentrações de Ca nas raízes laterais finas e nas ectomicorrizas de eucalipto.

Evaluation of statistical and geostatistical models of digital soil properties mapping in tropical mountain regions

Soil properties have an enormous impact on economic and environmental aspects of agricultural production. Quantitative relationships between soil properties and the factors that influence their variability are the basis of digital soil mapping. The predictive models of soil properties evaluated in this work are statistical (multiple linear regression-MLR) and geostatistical (ordinary kriging and co-kriging). The study was conducted in the municipality of Bom Jardim, RJ, using a soil database with 208 sampling points. Predictive models were evaluated for sand, silt and clay fractions, pH in water and organic carbon at six depths according to the specifications of the consortium of digital soil mapping at the global level (GlobalSoilMap). Continuous covariates and categorical predictors were used and their contributions to the model assessed. Only the environmental covariates elevation, aspect, stream power index (SPI), soil wetness index (SWI), normalized difference vegetation index (NDVI), and b3/b2 band ratio were significantly correlated with soil properties. The predictive models had a mean coefficient of determination of 0.21. Best results were obtained with the geostatistical predictive models, where the highest coefficient of determination 0.43 was associated with sand properties between 60 to 100 cm deep. The use of a sparse data set of soil properties for digital mapping can explain only part of the spatial variation of these properties. The results may be related to the sampling density and the quantity and quality of the environmental covariates and predictive models used.