Genotoxicity in Brazilian coal miners and its associated factors.

The present study aims to evaluate the potential genotoxic and associated factors among coal miners, divided by degree of exposure. Blood and buccal smears were collected from 158 workers, who actively participate in different activities in coal mining, and 48 individuals living in the same city but do not have participation in coal mining activities (control group). The workers were divided into three different groups, according to the level of contact with coal extraction. A questionnaire intended to identify factors associated with DNA damage was performed in participants. The results regarding oral mucosa micronucleus test showed a significant difference ( p < 0.001) of the worker groups 1 and 2 in relation to the control group, where the group 1 has a higher degree of exposure to coal than group 2. For the lymphocyte micronucleus test and comet assay, there was no significant difference between the exposed groups and control group. There is an association between the outcome and the fact of living in the municipality of the mining company and the exposure to radiation in the last 12 months. Besides, the multivariate analysis showed an association of the tail moment with radiation exposure in the last 12 months. Thus, the findings of this study reveal genotoxicity in oral mucosa cells of workers exposed to coal and that workers with higher degree of contact with coal have a more pronounced response.

Fracción vascular estromal de tejido adiposo: cómo obtener células madre y su rendimiento de acuerdo a la topografía de las áreas donantes: estudio preliminar / Stromal vascular fraction from fat tissue: obtaining stem cells and their yield according to the topography of the donor areas: previous note

La obtención de tejido adiposo supone un nuevo y prometedor mercado de trabajo para los cirujanos plásticos, ya que los bancos de tejidos escogerán de forma acertada la grasa como el medio más fácil para obtener fuentes de células madre de alto rendimiento, en la medida en que este tejido es capaz de producir al menos cinco veces más unidades formadores de colonias (UFCs) que la médula ósea. El objetivo del presente trabajo es mostrar lo que se puede esperar del tejido adiposo como origen de células adultas de fracción vacularestromal (FVE), y señalar las mejores áreas del cuerpo humano para ser elegidas como donantes de tejido adiposo, extraído mediante liposucción. Describimos la rutina seguida para la obtención de células de FVE mediante la digestión de las muestras de tejido adiposo humano con colagenasa. En el momento de su recolección, esas células presentaban una viabilidad de 92+/- 1% basada en exclusión por Azul de Trypan. Las células de FVE recontadas después de permanecer48 horas en medio de cultivo de Eagle modificado por Dulbecco(DMEM), dentro de una cámara de Neubauer, tras lo cual el rendimiento medio de las células de FVE fue de 7,2 +/- 1,3 x 103células por mililitro de tejido lipoaspirado. En conclusión, pensamos que supone un desafío en la actualida del mejorar las estrategias para la obtención de células de FVE. Este trabajo, por ahora preliminar, muestra que las células de FVE pueden ser fácilmente obtenidas por medio de lipoaspiración. La comparación entre las diferentes áreas donantes, mostró un rendimiento22% más alto para las células de FVE cuando el tejido adiposo había sido obtenido del tronco, en comparación a cuando lo había sido delos miembros (AU)

The harvest of adipose tissue will be a promising labor marketing for plastic surgeons, since tissue banks will certainly choose fat as the easiest way to obtain a high-yield source of stem cells, as this type of tissue can produce at least five times more colony-forming units (CFUs) than bone marrow extracts. The aim of this study is to show what can be expected from fat tissues as an origin of adult stromal vascular fraction (SVF) cells, and to evaluate the best areas to be elected as donor sites within the human body, all obtained by liposuction. The routine to obtain SVF cells by collagenase digestion of human adipose tissue samples was described. At the time of harvest, these cells displayed a viability of 92+/- 1% based on Try pan Blue exclusion, SVF cells were counted after 48 hours culture in Dulbecco´s modified Eagle medium (DMEM) in a Neuberger counting chamber. The average yield of SVF cells was 7,2 +/- 1,3 x 103 cells per millilitre of liposuctioned tissue. As a conclusion, best strategies to obtain SVF cells are an important challenge nowadays. This study, although preliminary, showed that SVF may be easily obtained From liposuction. Comparison among different donor sites showed a 22% higher yield of SVF cells when fat tissue had been obtained from the trunk regions, when confronted with limbs (AU)

Immunoblot analysis of trypomastigote excreted-secreted antigens as a tool for the characterization of Trypanosoma cruzi strains and isolates.

An analysis of antibody recognition of Trypanosoma cruzi exoantigens by immunoblotting revealed a unique banding pattern that seems to be characteristic of each strain or isolate. Trypomastigote excreted-secreted antigens (TESA) present in supernatants of LLC-MK2 cells infected with 5 strains and 10 isolates of T. cruzi produced 13 different immunoblotting patterns. The same bands were observed when probed with acute-phase Chagas' disease serum or with serum from a rabbit immunized with the repetitive domain of T. cruzi transialidase recombinant protein (anti-shed acute-phase antigens). Three similar patterns were observed with TESA from 3 human isolates that probably belong to the same T. cruzi strain. When clone CL Brener, clone CL-14, and CL parental strain were analyzed, the same bands were observed, although they presented different biological behavior. These results suggest that immunoblotting analysis of TESA may be a useful tool for characterization of T. cruzi strains and isolates.

Trypanosoma cruzi genome project: biological characteristics and molecular typing of clone CL Brener.

Clone CL Brener is the reference organism used in the Trypanosoma cruzi Genome Project. CL Brener was obtained by cloning procedures from bloodstream trypomastigotes isolated from mice infected with the CL strain. The doubling time of CL Brener epimastigotes cultured at 28 degrees C in liver infusion-tryptose (LIT) medium is 58 +/- 13 h. Differentiation to metacyclic forms is induced by incubation of epimastigotes in LIT-20% Grace's medium. Metacyclics give very low parasitemia in mice, contrary to what is observed for blood forms which promote 100% mortality of the animals with inocula of 5 x 10(3) parasites. CL Brener blood forms are highly susceptible to nifurtimox, benznidazole and ketoconazole. Allopurinol is inefficient in the treatment of mice experimental infection. The clone infects mammalian cultured cells and performs the complete intracellular cycle at 33 and 37 degrees C. The molecular typing of CL Brener has been done by isoenzymatic profiles; sequencing of a 24S alpha ribosomal RNA gene domain and by schizodeme, randomly amplified polymorphic DNA and DNA fingerprinting analyses. For each typing approach the patterns obtained do not change after prolonged parasite subcultivation in LIT medium (up to 100 generations). The stability of the molecular karyotype of the clone was also confirmed.

Biological parameters and molecular markers of clone CL Brener--the reference organism of the Trypanosoma cruzi genome project.

Clone CL Brener is the reference organism used in the Trypanosoma cruzi Genome Project. Some biological parameters of CL Brener were determined: (a) the doubling time of epimastigote forms cultured in liver infusion-tryptose (LIT) medium at 28 degrees C is 58 +/- 13 hr; (b) differentiation of epimastigotes to metacyclic trypomastigotes is obtained by incubation in LIT-20% Grace's medium; (c) trypomastigotes infect mammalian cultured cells and perform the complete intracellular cycle at 33 and 37 degrees C; (d) blood forms are highly infective to mice; (e) blood forms are susceptible to nifurtimox and benznidazole. The molecular typing of CL Brener has been determined: (a) isoenzymatic profiles are characteristic of zymodeme ZB; (b) PCR amplification of a 24S alpha ribosomal RNA sequence indicates it belongs to T. cruzi lineage 1; (c) schizodeme, randomly amplified polymorphic DNA (RAPD) and DNA fingerprinting analyses were performed.