Growth and production of cowpea beans under potassium doses in soil of cerrado in Amapá, Brazil.

The cowpea bean [Vigna unguiculata (L.) Walp.], a legume of great socioeconomic importance, it was previously cultivated exclusively for subsistence and commercial purposes, especially in the North and Northeast regions. This crop has a low production cost and high nutritional value, in addition to a high potential for productivity growth and expansion to other regions. The objective of this work was to evaluate parameters of growth and production in cowpea culture, as a function of potassium fertilization in soil of the cerrado of Amapá. The parameters of growth and production of the cowpea culture were evaluated, as a function of potassium fertilization in the soil of the cerrado of Amapá. The experiment was conducted in a greenhouse, using a completely randomized experimental design, with four replications, in a 5x2 factorial scheme, totaling 40 experimental units, which were composed of plastic pots containing 7 dm3 of soil collected from the arable layer (0-20 cm ) of a typical Hyperdystrophic Yellow Argisol, with a sandy clay loam texture, in a cerrado area in the municipality of Porto Grande-AP. The factors consisted of the control treatment (without K), four doses of K (45, 90, 135 and 180 kg ha-1) in the form of potassium chloride, and two cowpea cultivars (Pretinho and BRS Tumucumaque). The cultivar BRS Tumucumaque shows better growth and production of cowpea plants. Doses of 90 kg ha-1 provided greater height (98.75 cm) and stem diameter (10.0 mm). As for production, the dose of 135 kg ha-1 caused greater grain weight gain (5.25 g) and dry mass of pods (13.92 g), and the doses of 90 and 180 kg ha-1 induced greater number and length of pods (3.16 pods) respectively. These results show better responsiveness of the BRS Tumucumaque cultivar at doses of 90, 135 and 180 kg ha-1 in the type of soil where the study was conducted.

Psittacara leucophthalmus (Aves: Psittacidae) como um novo hospedeiro de Paratanaisia bragai (Trematoda: Eucotylidae) no Brasil: achados clínicos e patológicos: relato de caso / Psittacara leucophthalmus as a new host of Paratanaisia bragai (Trematoda: Eucotylidae) in Brazil: clinical and pathological findings: case report

Paratanaisia bragai é um trematódeo que parasita rins e ureteres de aves domésticas e selvagens. Apesar de considerado pouco patogênico pode levar a complicações clínicas e morte em infecções severas. No presente estudo, um caso de parasitismo fatal em maritaca (Psittacara leucophthalmus) por P. bragai é relatado. A ave, oriunda da área urbana do município de Lavras, Minas Gerais, Brasil, teve manifestações clínicas de apatia, desidratação, dispneia e veio a óbito. Na necropsia foram observados rins aumentados de volume, pálidos, com superfície irregular e nodulações esbranquiçadas. Ao corte verificaram-se parasitos nos rins, que foram processados para montagem de lâminas permanentes e identificados segundo técnica de rotina como P. bragai. No exame histopatológico dos rins foram constatados infiltrado inflamatório linfoplasmocítico multifocal moderado, dilatação de túbulos e focos de regeneração tubular, associados a fibrose intersticial moderada no córtex renal. Na medula renal havia infiltrado de macrófagos, heterófilos, eosinófilos e células gigantes multinucleadas associado a parasitos em ductos coletores dilatados. O parasitismo de P. leucophthalmus por P. bragai é relatado pela primeira vez. A importância de se considerar este parasito entre as possibilidades diagnósticas em aves com insuficiência renal é brevemente discutida.(AU)

Paratanaisia bragai is a trematode parasite of the kidneys and ureters of poultry and wild birds. Despite its low pathogenicity, this parasite can lead to several clinical complications and death in heavy infections. In the present study, a fatal case of parasitism by P. bragai in a specimen of the White-eyed Parakeet, Psittacara leucophthalmus, is reported. The bird, coming from the urban area of the county of Lavras, Minas Gerais, Brazil, was clinically evaluated and revealed apathy, dehydration, dyspnea, and death. The gross findings were pale and enlarged kidneys, which also had irregular surface with whitish nodulations. Parasites were observed on cutting surface of the renal parenchyma. They were processed for assembly of permanent slides and identified as P. bragai according to routine technique. The histologic findings were mild multifocal lymphoplasmacytic infiltrate, tubular dilatation and foci of tubular regeneration related to mild interstitial fibrosis in the renal cortex, and infiltration of macrophages, heterophils, eosinophils and multinucleated giant cells associated with metazoan parasites in the collecting ducts in renal medulla. The parasitism of P. leucophthalmus by P. bragai is reported for the first time. The importance of considering this parasite among the diagnostic possibilities in birds with renal insufficiency is briefly discussed.(AU)

Outbreak of Neisseria meningitidis C in workers at a large food-processing plant in Brazil: challenges of controlling disease spread to the larger community.

SUMMARYAn outbreak of meningococcal disease (MD) with severe morbidity and mortality was investigated in midwestern Brazil in order to identify control measures. A MD case was defined as isolation of Neisseria meningitidis, or detection of polysaccharide antigen in a sterile site, or presence of clinical purpura fulminans, or an epidemiological link with a laboratory-confirmed case-patient, between June and August 2008. In 8 out of 16 MD cases studied, serogroup C ST103 complex was identified. Five (31%) cases had neurological findings and five (31%) died. The attack rate was 12 cases/100 000 town residents and 60 cases/100 000 employees in a large local food-processing plant. We conducted a matched case-control study of eight primary laboratory-confirmed cases (1:4). Factors associated with illness in single variable analysis were work at the processing plant [matched odds ratio (mOR) 22, 95% confidence interval (CI) 2·3-207·7, P<0·01], and residing <1 year in Rio Verde (mOR 7, 95% CI 1·11-43·9, P<0·02). Mass vaccination (>10 000 plant employees) stopped propagation in the plant, but not in the larger community.

Beyond flat weals: validation of a three-dimensional imaging technology that will improve skin allergy research.

Skin-prick tests (SPTs) are a standard way to test for sensitizations to allergens, but to date, techniques that allow for high-quality measurements of the resulting weals for research purposes are lacking. In this study, we assessed a new three-dimensional (3D) imaging technology for its accuracy and consistency. We found that this new technology showed very little intraoperator and interoperator variation for repeated measurements of a model of known area by each of two operators. We also found that repeated measurements of the same object over 4 months showed virtually no variation. Finally, 3D imaging was superior to traditional ruler measurements for assessing SPT reactions to histamine and allergen. For high-quality measurements of SPT reactions, 3D imaging is accurate, consistent and reliable.

The dalbergioid legumes (Fabaceae): delimitation of a pantropical monophyletic clade.

A monophyletic pantropical group of papilionoid legumes, here referred to as the "dalbergioid" legumes, is circumscribed to include all genera previously referred to the tribes Aeschynomeneae and Adesmieae, the subtribe Bryinae of the Desmodieae, and tribe Dalbergieae except Andira, Hymenolobium, Vatairea, and Vataireopsis. This previously undetected group was discovered with phylogenetic analysis of DNA sequences from the chloroplast trnK (including matK) and trnL introns, and the nuclear ribosomal 5.8S and flanking internal transcribed spacers 1 and 2. All dalbergioids belong to one of three well-supported subclades, the Adesmia, Dalbergia, and Pterocarpus clades. The dalbergioid clade and its three main subclades are cryptic in the sense that they are genetically distinct but poorly, if at all, distinguished by nonmolecular data. Traditionally important taxonomic characters, such as arborescent habit, free stamens, and lomented pods, do not provide support for the major clades identified by the molecular analysis. Short shoots, glandular-based trichomes, bilabiate calyces, and aeschynomenoid root nodules, in contrast, are better indicators of relationship at this hierarchical level. The discovery of the dalbergioid clade prompted a re-analysis of root nodule structure and the subsequent finding that the aeschynomenoid root nodule is synapomorphic for the dalbergioids.

Overexpression of miniexon gene decreases virulence of Leishmania major in BALB/c mice in vivo.

During the construction of a physical map for Leishmania major (LV39) chromosome 2 we have rescued and characterized a L. major (LV39) derived genomic clone bearing solely as insert a long stretch of the miniexon gene array. The recombinant was devised as a tool to study the effect of miniexon overexpression on virulence and growth advantage. Such clone, 32D05, contains approximately 40 kb of the miniexon tandem array. We have examined the course of infection in susceptible BALB/c mice inoculated with transfectants carrying 32D05 as an episome. The study was carried out in two different clonal lines of L. major: virulent line LV39 (clone 5) and avirulent LT252 (CC1 clone). The results presented here indicate that high levels of miniexon expression affect negatively the ability of once virulent lines to induce lesions when injected in susceptible mice.

Resolution of an infection with Leishmania braziliensis confers complete protection to a subsequent challenge with Leishmania major in BALB/c mice.

Both Leishmania major and L. braziliensis induce cutaneous leishmaniasis in BALB/c mice. Whereas BALB/c mice die of infection with L. major, they cure an infection with L. braziliensis. We report here that after curing an infection with L. braziliensis, BALB/c mice are resistant to challenge with L. major. When challenged with L. major, L. braziliensis pre-treated BALB/c mice mounted a delayed-type hypersensitivity response to L. major and produced high amounts of interferon-gamma (IFN-gamma) but low amounts of interleukin-4. The IFN-gamma produced by the L. braziliensis pre-infected mice was involved in the protection seen against L. major challenge since treating the mice with a neutralizing anti-IFN-gamma abrogated the protection. This suggests that cross-reactive antigen epitopes exist between L. braziliensis and L. major and that pre-infection with L. braziliensis primes BALB/c mice to epitopes on L. major that can elicit a protective Th1 response to the parasite.

Histologic characterization of experimental cutaneous leishmaniasis in mice infected with Leishmania braziliensis in the presence or absence of sand fly vector salivary gland lysate.

Leishmania braziliensis is the causative agent of human cutaneous leishmaniasis in parts of the New World. In the murine model of infection, L. braziliensis does not produce severe or lasting cutaneous lesions in either BALB/c or C3H mice. However, when the parasites are injected into BALB/c mice with salivary gland lysate of the sand fly vector for the parasite, infection is significantly enhanced, as measured by lesion size, parasite burden, and the outcome of infection. Histologic examination of these cutaneous lesions showed that initially, nodular and diffuse dermal infiltrates of neutrophils, eosinophils, and histiocytes occurred in all mice. Over time, the saliva-free lesions progressed to small organized granulomas of epithelioid macrophages that contained few parasites, with eventual resolution of inflammation and mild dermal fibrosis. The saliva-associated lesions progressed to extensive, poorly organized accumulations of heavily parasitized epithelioid macrophages, with persistent neutrophils and eosinophils, and minimal fibroplasia. These results indicate that sand fly salivary gland lysate markedly modifies the inflammatory response to infection with L. braziliensis.

Analysis of the immune responses of mice to infection with Leishmania braziliensis.

Leishmania major and Leishmania braziliensis both cause cutaneous leishmaniasis, but the former kills BALB/c mice while the latter is killed by the mice. This killing of L. braziliensis occurred by a gamma interferon-dependent mechanism, potentially made possible by the observed lack of high interleukin-4 production.

A simple method for quantifying Leishmania in tissues of infected animals.

In experimental animals infected with Leishmania major, the size of cutaneous lesions of the parasite often does not correlate with the number of parasites within the lesion. Indeed, cutaneous lesions can heal, but still contain parasites. Thus, the ability to determine parasite burden in infected animals becomes important, especially when assessing vaccines that are intended to induce sterilizing immunity. Here, Hermenio Lima, Julie Bleyenberg and Richard Titus describe a simple technique for enumerating Leishmania in infected tissue. It is hoped that this technique will allow all researchers working with Leishmania (especially those in countries where leishmaniasis is endemic) to determine parasite burden easily in infected animals.

Effects of sand fly vector saliva on development of cutaneous lesions and the immune response to Leishmania braziliensis in BALB/c mice.

The saliva of the sand fly vector of leishmaniasis significantly enhanced infection with doses of >10(4) Leishmania braziliensis parasites in BALB/c mice. With a dose of 10(7) L. braziliensis parasites, 60 to 70% of the mice developed lifetime infections. Mice infected with L. braziliensis plus saliva produced two- to threefold more interleukin-4 than did mice infected with L. braziliensis alone. Treatment with a neutralizing anti-interleukin-4 antibody abrogated the effects of the saliva.

American cutaneous leishmaniasis: in situ characterization of the cellular immune response with time.

The cellular nature of the infiltrate in the skin of patients with American cutaneous leishmaniasis was characterized by immunohistochemistry. The study population consisted of patients in Ceara, Brazil, an area where Leishmania braziliensis is endemic. Biopsies were taken from lesions present for 0.5-4 months duration and sections were stained with antibodies to T cells, T cell subsets, B cells, and macrophage markers to quantitate these cell types. The T cells accounted for 37.0 +/- 7.6% (mean +/- SD) of the infiltrate. The average percentages of CD4- and CD8-positive T cells were similar to each other, 20.4 +/- 9.0% and 19.9 +/- 6.7%, respectively. Interleukin-2 receptor-positive cells and B cells were infrequent, 3.7 +/- 3.0% and 2.3 +/- 3.1%, respectively. When the relationship between the age of the lesion at biopsy and the cellular phenotype was examined, it was noted that the percentage of positive cells remained fixed for all cell types except for that of gamma delta cells, which decreased with time. It is likely that gamma delta T cells are important in the early phase of the immune response to L. braziliensis and may, in general, be important in the early immune response of granulomatous diseases.