Pathogens and microorganisms in the mangrove oyster Crassostrea gasar cultivated in an estuarine environment in Northeast Brazil.

Estuaries are important ecosystems due to the ecological services they provide, acting as nurseries for many species of fish and invertebrates, and are also used as environments for the extraction and cultivation of mollusks. Oysters are animals that filter water to obtain oxygen and nutrients. In this process, they can bioaccumulate microorganisms and chemical substances in their tissues. The growth of mollusk culture in Northeastern Brazil requires the health identification of cultivated oysters through the quantification of the potentially harmful microbiota accumulated in the animals. Therefore, the present work aims to quantify and identify bacteria and possible pathogens found in the tissues of cultivated oysters and their culture waters. The Most Probable Number of Coliforms (MPN) in oysters and water were considered suitable according to the Brazilian current legislation, Vibrio sp. obtained low colonization and Salmonella sp. was not observed. The prevalence of microorganisms potentially pathogenic to oysters was 33.7%, highlighting metazoans and Nematopsis sp., however, the intensity of the infestation of these organisms was moderate. The low contamination of oysters demonstrates that this culture environment is promising for this activity. However, continuous environmental and sanitary monitoring is fundamental to guarantee the safety of the culture waters and the sustainability of aquaculture activities.

Genomic characterization of MDR/XDR-TB in Kazakhstan by a combination of high-throughput methods predominantly shows the ongoing transmission of L2/Beijing 94-32 central Asian/Russian clusters.

BACKGROUND: Kazakhstan remains a high-burden TB prevalence country with a concomitent high-burden of multi-drug resistant tuberculosis. For this reason, we performed an in depth genetic diversity and population structure characterization of Mycobacterium tuberculosis complex (MTC) genetic diversity in Kazakhstan with both patient and community benefit. METHODS: A convenience sample of 700 MTC DNA cultures extracts from 630 tuberculosis patients recruited from 12 out of 14 regions in Kazakhstan, between 2010 and 2015, was independently studied by high-throughput hybridization-based methods, TB-SPRINT (59-Plex, n = 700), TB-SNPID (50-Plex, n = 543). DNA from 391 clinical isolates was successfully typed by two methods. To resolve the population structure of drug-resistant clades in more detail two complementary assays were run on the L2 isolates: an IS6110-NTF insertion site typing assay and a SigE SNP polymorphism assay. RESULTS: Strains belonged to L2/Beijing and L4/Euro-American sublineages; L2/Beijing prevalence totaled almost 80%. 50% of all samples were resistant to RIF and to INH., Subtyping showed that: (1) all L2/Beijing were "modern" Beijing and (2) most of these belonged to the previously described 94-32 sublineage (Central Asian/Russian), (3) at least two populations of the Central Asian/Russian sublineages are circulating in Kazakhstan, with different evolutionary dynamics. CONCLUSIONS: For the first time, the global genetic diversity and population structure of M. tuberculosis genotypes circulating in Kazakhstan was obtained and compared to previous local studies. Results suggest a region-specific spread of a very limited number of L2/Beijing clonal complexes in Kazakhstan many strongly associated with an MDR phenotype.

Understanding the relationship between Mycobacterium bovis spoligotypes from cattle in Latin American countries.

Spoligotyping is the most frequently used method for genotyping isolates of Mycobacterium bovis worldwide. In the current work, we compared spoligotypes from 1684 M. bovis isolates from Argentina (816), Brazil (412), Chile (66), Mexico (274) and Venezuela (116), obtained from cattle, humans, pigs, wild boars, farmed deer, goats, buffaloes, cats, and wild animals. A total of 269 different spoligotypes were found: 142 (8.4%) isolates presented orphan spoligotypes, whereas 1542 (91.6%) formed 113 different clusters. In cattle, SB0140 was the most representative spoligotype with 355 (24.6%) isolates, followed by SB0121 with 149 (10.3%) isolates. Clustering of spoligotypes ranged from 95.2% in Argentina to 85.3% in Mexico. Orphan spoligotypes were also variable, ranging from 23.7% in Mexico to 4.1% in Brazil. A large proportion of spoligotypes were common to the neighboring countries Argentina, Brazil and Chile. In conclusion, despite the diversity of spoligotypes found in the five countries studied, there are major patterns that predominate in these neighboring countries. These clusters may reflect a long-lasting active transmission of bovine tuberculosis or common historical origins of infection.

Tuberculosis caused by RDRio Mycobacterium tuberculosis is not associated with differential clinical features.

BACKGROUND: We recently described the Mycobacterium tuberculosis RD(Rio) genotype, a clonally derived sublineage within the Latin American-Mediterranean (LAM) family. Genetic diversity of M. tuberculosis likely affects the clinical aspects of tuberculosis (TB). Prospective studies that address this issue are scarce and remain controversial. OBJECTIVE: To determine the association of differential clinical features of pulmonary TB with the RD(Rio) M. tuberculosis etiology. METHODS: Culture-proven pulmonary TB patients (n = 272) were clinically evaluated, including history, physical examination, chest X-ray and anti-human immunodeficiency virus serology. Isolates were classified as RD(Rio) or non-RD(Rio) M. tuberculosis by multiplex polymerase chain reaction and further spoligotyped. Clinical and M. tuberculosis genotype data were analyzed. RESULTS: RD(Rio) M. tuberculosis caused disease in 26.5% (72/270) of all TB cases. The LAM genotype, of which RD(Rio) strains are members, was responsible for 46.0% of the TB cases. Demographic data, major signs and symptoms, radiographic presentation, microbiological features and clinical outcomes were not significantly different among patients with TB caused by RD(Rio) and non-RD(Rio) strains. CONCLUSIONS: Disease caused by M. tuberculosis RD(Rio) strains was not clinically distinctive or more severe than disease caused by non-RD(Rio) strains in this series of TB patients. Larger prospective studies specifically designed to disclose differential clinical characteristics of TB caused by specific M. tuberculosis lineages are needed.

Comparação entre a técnica de substituição do ligamento redondo por implante de fascia lata bubalina preservada em glicerina e o uso de pino transarticular na redução e na estabilização da luxação coxofemoral experimentalmente induzida em cães / Comparation between the technique of substitution of the round ligamentum by glycerin-preserved bubaline fascia lata implant and the use of transarticular pin in the redution and stabilization of experimentally induzed coxofemoral luxation in dogs

Compararam-se duas técnicas cirúrgicas de redução e estabilização da articulação coxofemoral experimentalmente luxada em cães. Dois grupos de animais, submetidos às respectivas técnicas após a indução cirúrgica da luxação, foram acompanhados clínica e radiograficamente por um período de 60 dias, findos os quais, realizaram-se avaliações macroscópica e histológica e teste de tensiometria das articulações. Cada grupo foi constituído por oito animais, clinicamente sadios, com pesos entre 5 e 20kg. Os animais submetidos ao implante de fáscia apresentaram, ao exame físico, evolução da deambulação significativamente precoce em relação aos do grupo submetido ao implante de pino de Steinmann, além de menor grau de atrofia muscular. Os testes de tensiometria, as avaliações macroscópicas e radiográficas e os exames histológicos não diferiram entre os grupos, evidenciando também que ambas as técnicas não geraram alterações deletérias à articulação operada. Conclui-se que a técnica de estabilização da articulação coxofemoral com implante de fascia lata foi clinicamente eficaz e vantajosa quando comparada à técnica do pino transarticular.

It was compared both surgical techniques of reduction and stabilization of experimentally luxated coxofemoral join in dog. Two groups were submitted to the techniques after surgical induction of the luxation. All animals were clinically and radiografically observed during 60 days. After that, a macroscopic study, an histological exam, and a tensiometry test in the articulations were performed. Each group had eight healthy animals, weighting from 5 to 20kg. The most important advantage was related to the deambulation, which the animals submited to the facia lata implant showed a faster evolution after the surgery at the physical exam, and muscular atrophy in a smaller degree. The tensiometry tests, the radiographic and the histological exams did not present important differences between both groups, but they were useful to show that the two techniques did not cause alterations in the studied articulation. It can be concluded that the stabilization of the coxofemoral articulation using bubaline fascia lata implant was clinically efficient and more advantageous compared to the transarticular pin technique.

Immunological cytokine correlates of protective immunity and pathogenesis in leprosy.

The in vitro production of interferon (IFN)-gamma, interleukin (IL)-5, tumour necrosis factor (TNF)-alpha and IL-10 by blood mononuclear cells in response to whole Mycobacterium leprae and polyclonal stimulii of 23 individuals, representing a variety of conditions in relation to exposure/susceptibility to M. leprae, was assayed. In most cases, healthy household contacts of newly diagnosed multibacillary leprosy patients, designated exposed household contacts (EC), showed low-to-undetectable in vitro IFN-gamma production in addition to substantial TNF-alpha production in response to M. leprae. In contrast, peripheral blood mononuclear cells from previously exposed contacts (R) regarded as resistant-to-leprosy released low-to-moderate levels of IFN-gamma together with a mixed cytokine profile resembling a T helper (Th)0-type response. TNF-alpha/IL-10 ratios in response to M. leprae and Concanavalin A were significantly higher in EC than in R contacts suggesting a role for the TNF-alpha/IL-10 ratio in restraining mycobacteria proliferation and spreading early in infection. The cytokine profiles of leprosy patients were taken as reference points. Post-treatment lepromatous leprosy patients secreted relatively high levels of IL-10 in response to M. leprae, whereas one self-cured tuberculoid leprosy patient produced simultaneously high levels of IFN-gamma and TNF-alpha. In addition, the quantitative changes in the cytokines released by peripheral blood mononuclear cells in EC contacts after Bacille Calmette-Guérin (BCG) vaccination were investigated. Vaccination induced amplification of IFN-gamma production with a concomitant decrease in TNF-alpha/IL-10 ratios that resembled the cytokine pattern observed in R contacts. IFN-gamma production was observed in response to both a cross-reactive antigen (Ag 85) and a M. leprae-specific protein (MMP-I), which attests to a BCG nonspecific stimulation of the immune system, thereby casting these antigens as likely candidates for inclusion in a subunit vaccine against leprosy. Finally, a model for protective x pathologic response to mycobacteria is presented.

Improvement in the determination of mancozeb residues by the carbon disulfide evolution method using flow injection analysis.

The sample decomposition of the carbon disulfide evolution method for the determination of dithiocarbamate residues was carried out in a closed vial in the presence of hexane. The evolved carbon disulfide was extracted by the organic solvent and injected in a flow system for its quantification as copper complex. The conditions for batch decomposition, flow injection determination, and association of both were investigated with sodium diethyldithiocarbamate as model substance. An one-channel flow system was employed where the carrier stream was the ethanolic ethylenediamine/copper solution. The determination range was of 0. 01-1.26 microg of CS(2), with a relative standard deviation of 0.06% (n = 10), with a sample throughput of 45 samples/h. The association of the batch decomposition with the flow system was carried out with the fungicide mancozeb and was applied to the analysis of its residue in potato, lettuce, cucumber, and green bean crops. The approach allowed the analysis of 11 samples in triplicate in 2 h, with recoveries between 85% and 92% and relative standard deviation about 2%.

Serology and leprosy: immunoassays comparing immunoglobulin G antibody responses to 28- and 30-kilodalton proteins purified from Mycobacterium bovis BCG.

Two major proteins from Mycobacterium bovis BCG culture filtrates with molecular masses of 28 kDa (P28) and 30 kDa (P30), identified as components of the BCG 85 complex, were purified and used in enzyme-linked immunosorbent assays (ELISAs) for the determination of specific immunoglobulin G (IgG) levels in patients with leprosy or tuberculosis or with exposure to these diseases. High reactivity to both antigens was observed with sera from lepromatous leprosy patients, whereas antibody levels in sera from paucibacillary leprosy patients were not significantly different from those in sera from healthy individuals from an area in which leprosy is endemic. High IgG responses were also found in some contacts of lepromatous leprosy patients. A comparison of the levels of anti-P28 and anti-P30 within the multibacillary leprosy patient group showed much higher IgG reactivity to P28 than to P30, suggesting that the antibody response of lepromatous patients is directed predominantly against the 28-kDa protein. A high degree of correlation in values of ELISAs based on P28 and on the phenolic glycolipid of Mycobacterium leprae was observed in all groups analyzed. The potential use of an assay based on the 28-kDa protein to selectively distinguish individuals destined to develop multibacillary leprosy is discussed, as also is the likelihood that the 28-kDa-30-kDa complex, part of the fibronectin-binding family, is an important component of M. leprae.