The Fate of Chrysotile-Induced Multipolar Mitosis and Aneuploid Population in Cultured Lung Cancer Cells

Chrysotile is one of the six types of asbestos, and it is the only one that can still be commercialized in many countries. Exposure to other types of asbestos has been associated with serious diseases, such as lung carcinomas and pleural mesotheliomas. The association of chrysotile exposure with disease is controversial. However, in vitro studies show the mutagenic potential of chrysotile, which can induce DNA and cell damage. The present work aimed to analyze alterations in lung small cell carcinoma cultures after 48 h of chrysotile exposure, followed by 2, 4 and 8 days of recovery in fiber-free culture medium. Some alterations, such as aneuploid cell formation, increased number of cells in G2/M phase and cells in multipolar mitosis were observed even after 8 days of recovery. The presence of chrysotile fibers in the cell cultures was detected and cell morphology was observed by laser scanning confocal microscopy. After 4 and 8 days of recovery, only a few chrysotile fragments were present in some cells, and the cellular morphology was similar to that of control cells. Cells transfected with the GFP-tagged alpha-tubulin plasmid were treated with chrysotile for 24 or 48 h and cells in multipolar mitosis were observed by time-lapse microscopy. Fates of these cells were established: retention in metaphase, cell death, progression through M phase generating more than two daughter cells or cell fusion during telophase or cytokinesis. Some of them were related to the formation of aneuploid cells and cells with abnormal number of centrosomes.

Local atomic structure in tetragonal pure ZrO(2) nanopowders

The local atomic structures around the Zr atom of pure (undoped) ZrO(2) nanopowders with different average crystallite sizes, ranging from 7 to 40 nm, have been investigated. The nanopowders were synthesized by different wet-chemical routes, but all exhibit the high-temperature tetragonal phase stabilized at room temperature, as established by synchrotron radiation X-ray diffraction. The extended X-ray absorption fine structure (EXAFS) technique was applied to analyze the local structure around the Zr atoms. Several authors have studied this system using the EXAFS technique without obtaining a good agreement between crystallographic and EXAFS data. In this work, it is shown that the local structure of ZrO(2) nanopowders can be described by a model consisting of two oxygen subshells (4 + 4 atoms) with different Zr-O distances, in agreement with those independently determined by X-ray diffraction. However, the EXAFS study shows that the second oxygen subshell exhibits a Debye-Waller (DW) parameter much higher than that of the first oxygen subshell, a result that cannot be explained by the crystallographic model accepted for the tetragonal phase of zirconia-based materials. However, as proposed by other authors, the difference in the DW parameters between the two oxygen subshells around the Zr atoms can be explained by the existence of oxygen displacements perpendicular to the z direction; these mainly affect the second oxygen subshell because of the directional character of the EXAFS DW parameter, in contradiction to the crystallographic value. It is also established that this model is similar to another model having three oxygen subshells, with a 4 + 2 + 2 distribution of atoms, with only one DW parameter for all oxygen subshells. Both models are in good agreement with the crystal structure determined by X-ray diffraction experiments.

Crystallite size-dependent phases in nanocrystalline ZrO(2)-Sc(2)O(3)

ZrO(2)-10, 12 and 14 mol% Sc(2)O(3) nanopowders were prepared by using a nitrate-lysine gel-combustion synthesis. These materials were studied by synchrotron X-ray powder diffraction (SXPD) and Raman spectroscopy after calcination at different temperatures from 650 to 1200 degrees C, which led to samples with different average crystallite sizes, up to about 100 nm. The results from SXPD and Raman analyses indicate that, depending on Sc(2)O(3) content, the metastable t ''-form of the tetragonal phase or the cubic phase are fully retained at room temperature in nanocrystalline powders, provided an average crystallite sizes lower than similar to 30 nm. By contrast, powders with larger average crystallite sizes exhibit the stable rhombohedral, beta and gamma, phases and do not retain or very partially retain the metastable t '' and cubic ones.

Protein preparation, crystallization and preliminary X-ray analysis of Trypanosoma cruzi nucleoside diphosphate kinase 1

The flagellated protozoan parasite Trypanosoma cruzi is the aetiological agent of Chagas disease. Nucleoside diphosphate kinases (NDPKs) are enzymes that are involved in energy management and nucleoside balance in the cell. T. cruzi TcNDPK1, a canonical isoform, was overexpressed in Escherichia coli as an N-terminally poly-His-tagged fusion protein and crystallized. Crystals grew after 72 h in 0.2 M MgCl(2), 20% PEG 3350. Data were collected to 3.5 angstrom resolution using synchrotron X-ray radiation at the National Synchrotron Light Laboratory (Campinas, Brazil). The crystals belonged to the trigonal space group P3, with unit-cell parameters a = b = 127.84, c = 275.49 angstrom. Structure determination is under way and will provide relevant information that may lead to the first step in rational drug design for the treatment of Chagas disease.

HYBRID, SUBSPECIES, OR SPECIES? THE VALIDITY AND TAXONOMIC STATUS OF PHAETHORNIS LONGUEMAREUS AETHOPYGA ZIMMER, 1950 (TROCHILIDAE)

Phaethornis longuemareus aethopyga was described by John T. Zimmer in 1950 and treated as a valid subspecies until it was proposed that the three known specimens were hybrids between R ruber and P. rupurumii amazonicus. On the basis of some recently collected specimens, we reevaluated the validity of P. l. aethopyga. Despite showing some differences related to age and sex, all specimens agree in the general plumage pattern and are fully diagnosable when compared with any other taxon of the genus. The hypothesis of a hybrid origin becomes unsustainable when one notes that (1) P. l. aethopyga has characters that are unique and absent in the purported parental species, such as the white outer margins at the base of the rectrices; and (2) P. l. aethopyga occurs far from the distribution of one of the alleged parental species. Furthermore, field data show that P. l. aethopyga has attributes typical of a valid and independent taxon, such as lekking behavior. Therefore, given its overall diagnosis, P. aethopyga could at least be treated as a phylogenetic species. Yet its morphological and vocal distinctiveness with respect to other Phaethornis spp. in the ""Pygmornis group"" is greater than that observed between some species pairs traditionally regarded as separate biological species within the group, which supports its recognition as a species under the biological species concept. Received 13 July 2008, accepted 9 March 2009.

Middle Pleistocene sea surface temperature in the Brazil-Malvinas Confluence Zone: Paleoceanographic implications based on planktonic foraminifera

We reconstructed Middle Pleistocene surface hydrography in the western South Atlantic based on planktonic foraminiferal assemblages, modern analog technique and Globorotalia truncatulinoides isotopic ratios of core SP1251 (38 degrees 29.7`S / 53 degrees 40.7`W / 3400 m water depth). Biostratigraphic analysis suggests that sediments were deposited between 0.3 and 0.12 Ma and therefore correlate to Marine Isotopic Stage 6 or 8. Faunal assemblage-based winter and summer SST estimates suggest that the western South Atlantic at 38 degrees S was 4-6 degrees C colder than at present, within the expected range for a glacial interval. High relative abundances of subantarctic species, particularly the dominance of Neogloboquadrina pachyderma (left), support lower than present SSTs throughout the recorded period. The oxygen isotopic composition of G. truncatulinoides suggests a northward shift of the Brazil-Malvinas Confluence Zone and of the associated mid-latitude frontal system during this Middle Pleistocene cold period, and a stronger than present influence of superficial subantarctic waters and lowering in SSTs at our core site during the recorded Middle Pleistocene glacial.

Matrix Method for Acoustic Levitation Simulation

A matrix method is presented for simulating acoustic levitators. A typical acoustic levitator consists of an ultrasonic transducer and a reflector. The matrix method is used to determine the potential for acoustic radiation force that acts on a small sphere in the standing wave field produced by the levitator. The method is based on the Rayleigh integral and it takes into account the multiple reflections that occur between the transducer and the reflector. The potential for acoustic radiation force obtained by the matrix method is validated by comparing the matrix method results with those obtained by the finite element method when using an axisymmetric model of a single-axis acoustic levitator. After validation, the method is applied in the simulation of a noncontact manipulation system consisting of two 37.9-kHz Langevin-type transducers and a plane reflector. The manipulation system allows control of the horizontal position of a small levitated sphere from -6 mm to 6 mm, which is done by changing the phase difference between the two transducers. The horizontal position of the sphere predicted by the matrix method agrees with the horizontal positions measured experimentally with a charge-coupled device camera. The main advantage of the matrix method is that it allows simulation of non-symmetric acoustic levitators without requiring much computational effort.

Early onset of primary hypogonadism revealed by serum anti-Mullerian hormone determination during infancy and childhood in trisomy 21

Male patients with an extra sex chromosome or autosome are expected to present primary hypogonadism at puberty owing to meiotic germ-cell failure. Scarce information is available on trisomy 21, a frequent autosomal aneuploidy. Our objective was to assess whether trisomy 21 presents with pubertal-onset, germ-cell specific, primary hypogonadism in males, or whether the hypogonadism is established earlier and affects other testicular cell populations. We assessed the functional status of the pituitary-testicular axis, especially Sertoli cell function, in 117 boys with trisomy 21 (ages: 2 months-20 year). To compare with an adequate control population, we established reference levels for serum anti-Mullerian hormone (AMH) in 421 normal males, from birth to adulthood, using a recently developed ultrasensitive assay. In trisomy 21, AMH was lower than normal, indicating Sertoli cell dysfunction, from early infancy, independently of the existence of cryptorchidism. The overall prevalence rate of AMH below the 3rd percentile was 64.3% in infants with trisomy 21. Follicle-stimulating hormone was elevated in patients <6 months and after pubertal onset. Testosterone was within the normal range, but luteinizing hormone was elevated in most patients <6 months and after pubertal onset, indicating a mild Leydig cell dysfunction. We conclude that in trisomy 21, primary hypogonadism involves a combined dysfunction of Sertoli and Leydig cells, which can be observed independently of cryptorchidism soon after birth, thus prompting the search for new hypotheses to explain the pathophysiology of gonadal dysfunction in autosomal trisomy.

A gest??o de pessoas como um recurso estrat??gico

O texto examina as estrat??gias e os sistemas que devem ser considerados para se alcan??ar a melhor gest??o de recursos humanos no setor p??blico. Inicialmente, baseado em tr??s modelos tradicionais de administra????o p??blica, sugere uma abordagem hol??stica para aumentar a efetividade da gest??o. Em seguida, defende a id??ia de um ??rg??o ???guardi??o??? central, que considere o princ??pio do m??rito e que divida com os ??rg??os de linha a responsabilidade sobre a GRH. Mostra, ainda, a import??ncia de institucionalizar os valores da imparcialidade, do profissionalismo e da responsividade. Ao tratar da profissionaliza????o da GRH, ressalta a necessidade de uma pol??tica que defina como a gest??o de pessoas contribuir?? para o alcance de objetivos governamentais. Para isso, prop??e a aplica????o de um modelo integrado baseado em compet??ncias e o desenvolvimento de uma pol??tica salarial que permita a atra????o e reten????o de talentos no setor p??blico. Ao final, o texto apresenta os pr??s e contras da gest??o por desempenho, bem como os desafios de um redimensionamento organizacional no servi??o p??blico.

Mecanismos de sustentabilidade das pol??ticas de vigil??ncia sanit??ria: um olhar sobre a Anvisa

Este artigo pretende ser uma colabora????o para o debate na ??rea de gest??o estrat??gica da sa??de, com foco na vigil??ncia sanit??ria. Nele buscou-se compreender as configura????es organizacionais que viabilizam (maior) ades??o ?? formula????o de estrat??gias em uma ag??ncia reguladora, a Ag??ncia Nacional de Vigil??ncia Sanit??ria (Anvisa). Foram consultados documentos da Anvisa dispon??veis ao p??blico na Internet, al??m de documentos internos nos arquivos da ??rea de planejamento da Ag??ncia. Foram analisados dois momentos de planejamento estrat??gico da Ag??ncia, ?? luz dos aspectos relacionados aos conceitos de poder e cultura, da configura????o organizacional, al??m das formas de controle sobre as ag??ncias reguladoras. Conclui-se que mecanismos que refor??am a transpar??ncia institucional levam ao sucesso de uma formula????o estrat??gica e ?? maior sustentabilidade das pol??ticas.

Suporte de identifica????o e enfrentamento de situa????es-problema (Siesp)

Desenvolve e aplica o Suporte de Identifica????o e Enfrentamento de Situa????es Problema (Siesp). Sob o ponto de vista descritivo, esse recurso busca ampliar e explicitar informa????es sobre situa????es problema existentes nas organiza????es, mas que n??o s??o facilmente percebidas. Sob o ponto de vista prescritivo, esse Suporte baseado na Metodologia de Sistemas Flex??veis (MSF) busca ampliar e explicitar conhecimentos a serem aproveitados para converter decis??es bem informadas em a????es oportunas de confronto da situa????o antes enquadrada como problem??tica, porque ela causa ou tem potencial para causar consequ??ncias indesej??veis. O contexto focalizado ?? o sistema de informa????o da Ag??ncia Nacional de Energia El??trica (ANEEL). O resultado desse trabalho ?? relatado neste artigo. Novos trabalhos poder??o ser realizados com o prop??sito de aplicar o SIESP em outras realidades organizacionais, com vistas a consolid??-lo como recurso ??til destinado a ampliar, explicitar e aproveitar conhecimentos.

A lei geral de comunica????o eletr??nica de massa e a qualidade da programa????o televisiva

O presente artigo pretende analisar a quest??o da qualidade da programa????o na televis??o brasileira a partir da proposta de um novo marco regulat??rio para o setor de comunica????o social eletr??nica. Essa nova lei, entre outras disposi????es, ir?? regulamentar o artigo 221 da Constitui????o Federal, que trata dos princ??pios pelos quais o conte??do televisivo deve pautar-se. Com isso, define-se qualidade levando-se em considera????o dois aspectos: diversidade e ressalvas ?? liberdade de express??o, ambos previstos na Constitui????o Federal. A partir dessa conceitua????o, prop??e-se a instrumentaliza????o do controle social sobre o conte??do televisivo e a garantia de meios para a diversidade da programa????o. Com rela????o ao primeiro aspecto, recomenda-se a atua????o transparente de uma futura ag??ncia reguladora e a implementa????o de mecanismo de controle individual da programa????o. No que tange ?? diversidade, ressalta-se a import??ncia do fortalecimento das televis??es p??blicas e medidas governamentais no sentido de estimular a multiprograma????o propiciada pelo advento da tecnologia digital.

Insulamento burocr??tico, accountability e transpar??ncia: dez anos de regula????o da Ag??ncia Nacional de Vigil??ncia Sanit??ria

Este artigo estuda os instrumentos e mecanismos de transpar??ncia e accountability das ag??ncias reguladoras brasileiras. Por meio da caracteriza????o dos processos de controle, participa????o e acesso a informa????es da Ag??ncia Nacional de Vigil??ncia Sanit??ria (Anvisa), analisa-se como as ag??ncias t??m utilizado tais instrumentos e mecanismos para acolher e processar diversos interesses do processo regulat??rio, promover a estabilidade das regras do jogo e refor??ar a sua legitimidade no ambiente pol??tico e social em que elas est??o inseridas. Foram utilizados dados relativos aos diversos instrumentos de transpar??ncia e accountability, bem como ??s inst??ncias e mecanismos de participa????o da sociedade no processo regulat??rio da Anvisa. Conclui-se que a accountability das ag??ncias ?? um contrafluxo ?? tend??ncia de insulamento, ao mesmo tempo em que se pode configurar um esfor??o de reconhecimento pela sociedade da chegada de um novo aparato institucional no Estado brasileiro: as ag??ncias reguladoras.

Desempenho organizacional e arranjo federativo: o slack da Sudene e o colapso na gest??o da pol??tica de planejamento regional

Este artigo procura explicar as raz??es do colapso na gest??o do sistema de planejamento regional no Brasil, debru??ando-se sobre a extin????o da Sudene no final da d??cada de 1990, como estudo de caso. Para tanto, utiliza-se o modelo de sa??da, voz e lealdade de Hirschman, para destacar o funcionamento dos mecanismos promotores do slack organizacional nessa ag??ncia de governo, e sua subsequente extin????o. Assim, sustenta-se o argumento de que a implementa????o de modelo federativo fortemente descentralizado, a partir da Constitui????o de 1988, produziu disfun????es operacionais em uma organiza????o dotada de estrutura decis??ria colegiada, deslegitimando-a, e conduzindo-a ?? extin????o.

A constru????o da Lei de Acesso ?? Informa????o P??blica no Brasil: desafios na implementa????o de seus princ??pios

Nos ??ltimos anos, diversos pa??ses t??m feito grandes modifica????es em suas legisla????es, na tentativa de proteger o direito de acesso ?? informa????o e adequar sua legisla????o interna ??s exig??ncias impostas por tratados internacionais. A Lei de Acesso ?? Informa????o brasileira (Lei n?? 12.527, de 2011) foi constru??da a partir dos par??metros internacionalmente reconhecidos. Esses par??metros incorporam novos conceitos que ampliam o entendimento comum sobre o princ??pio da publicidade e recomendam a ado????o do princ??pio da m??xima transpar??ncia. A nova lei ?? essencial para melhorar as condi????es de acesso ??s informa????es governamentais no Brasil, como ser?? mostrado na an??lise feita da experi??ncia dos Estados Unidos da Am??rica e do M??xico. Contudo, devido a dificuldades relacionadas especialmente ?? burocracia administrativa, o direito de acesso ?? informa????o tender?? a permanecer incompleto, enquanto n??o for incorporado a uma pol??tica p??blica capaz de traduzir esse direito em um conjunto de a????es governamentais que garantam sua efetividade.