Multidrug-resistant tuberculosis (MDRTB) has emerged as a major public health problem worldwide. To determine the incidence and risk factors associated with tuberculosis among contacts of MDRTB index cases, we studied human immunodeficiency virus-seronegative close contacts of 64 culture-confirmed MDRTB patients in Rio de Janeiro, Brazil. Between March 1988 and July 1992, tuberculosis developed in 17 (7.8%) of 218 previously healthy close contacts of 64 MDRTB index cases (1.6 cases per 1,000-person-months of contact). Among strains of Mycobacterium tuberculosis isolated from 13 contacts of 12 index cases, six (46%) had susceptibility patterns identical to those of their index cases, four (31%) had different patterns of resistance, and three (23%) were susceptible to all drugs. Tuberculosis developed more frequently in male contacts (p < 0.05), persons > or = 15 yr of age (p < 0.05), nonwhites (p < 0.001), and persons not previously vaccinated with bacillus Calmette-Guerin (BCG) (p < 0.05). The association of BCG vaccination with decreased risk of disease was significant even when this variable was controlled (by Cox's regression analysis) for age, sex, race, purified protein derivative (PPD) status, and isoniazid prophylaxis. BCG vaccination appears to offer protection against tuberculosis during prolonged exposures to persons with MDRTB, which identifies a novel and specific indication of BCG use.
The in vitro schistosomicidal effects of the essential oil of Ageratum conyzoides L. (Ac-EO) against adult worms of Schistosoma mansoni is reported in this paper. Concerning this activity, Ac-EO was considered to be active, but less effective than the positive control (praziquantel, PZQ) in terms of separation of coupled pairs, mortality, decrease in motor activity, and tegumental alterations. However, Ac-EO caused an interesting dose-dependent reduction in the number of eggs of S. mansoni. Precocene I (74.30%) and (E)-caryophyllene (14.23%) were identified as the two major constituents of Ac-EO. These compounds were tested individually and were found to be much less effective than Ac-EO and PZQ. A mixture of the two major compounds in a ratio similar to that found in the Ac-EO was also less effective than Ac-EO, thus revealing that there are no synergistic effects between these components. These results suggest that the essential oil of A. conyzoides is very promising for the development of new schistosomicidal agents.
. do Café, s/n, 14040-903 Ribeirão Preto -SP, BrasilRecebido em 1/7/10; aceito em 21/9/10; publicado na web em 27/10/10 LYCHNOPHORINAE (ASTERACEAE): A SURVEY OF ITS CHEMICAL CONSTITUENTS AND BIOLOGICAL ACTIVITIES. This work reviews the current literature about the chemical constituents and the biological activities of the subtribe Lychnophorinae (Vernonieae, Asteraceae). The notable secondary metabolites are sesquiterpene lactones of furanoheliangolide (goyazensolide and eremantholide types) and flavonoids. Some of its most investigated activities include its anti-inflammatory, analgesic, antimicrobial and cytotoxic activities, specially for the Lychnophora and Eremanthus species. The data presented on this paper not only displayed the role played by the Lychnophorinae species as a source of bioactive compounds, but also reinforced the need of further studies involving the species of such subtribe.
In Brazilian folk medicine, Tetradenia riparia (Hochst.) Codd.
(Lamiaceae) is used to treat toothaches and dental abscesses and diseases
induced by worms, bacteria, or fungi. This paper aims to investigate the
chemical composition and the antibacterial effects of the essential oil obtained
from Tetradenia riparia leaves (TR-EO) grown in Southeastern
Brazil against a representative panel of oral pathogens. We evaluated the
antibacterial activity of TR-EO in terms of the minimal inhibitory concentration
(MIC). We identified aromadendrene oxide (14.0%),
(E,E)-farnesol (13.6%), dronabinol (12.5%), and fenchone (6.2%)
as the major constituents of TR-EO. TR-EO displayed MIC values between 31.2 and
500 μg/mL, with the lowest MIC value being obtained against
Streptococcus mitis (31.2 μg/mL), S.
mutans (62.5 μg/mL), S. sobrinus (31.2 μg/mL), and
Lactobacillus casei (62.5 μg/mL). In time-kill experiments,
TR-EO demonstrated bactericidal activity against S. mutans
within the first 12 h, resulting in a curve profile similar to that of
chlorhexidine. These results revealed that the essential oil of
Tetradenia riparia displays promising activity against most
of the selected cariogenic bacteria, including Streptococcus
Resumo O artigo analisou a orientação empreendedora (OE) em suas dimensões – comportamento inovador, assunção de riscos, proatividade, autonomia, agressividade competitiva e redes de relações – e sua associação com o desempenho das empresas graduadas das incubadoras brasileiras. De modo específico, objetivou-se comparar os resultados desse estudo com o encontrado por A. C. M. Z. Santos e Alves (2009), a partir dos modelos de Miller (1983) e Lumpkin e Dess (1996). Utilizou-se a abordagem quantitativa e a técnica de modelagem de equações estruturais para uma amostra de 128 empresas do Brasil. Os principais resultados evidenciaram que a OE constitui-se como um modelo unidimensional, divergente do encontrado por A. C. M. Z. Santos e Alves (2009) em empresas incubadas. Verificou-se que a dimensão que contribuiu mais fortemente para a existência da OE foi a autonomia, e que as redes de relações, dimensão não mencionada até então pelos estudos anteriores, colaboraram de forma análoga às demais dimensões para a composição da OE.
The goal of the study was to evaluate the ability of filamentous fungi to biotransform the pentacyclic triterpene lupeol. The microbial transformations were carried out in shake flasks in different media. Experiments were also run with control flasks. Samples of each culture were taken every 24 hours, extracted with ethyl acetate, and analyzed by GC-MS. The biotransformation of lupeol by Aspergillus ochraceus and Mucor rouxii afforded two compounds in each culture, which were detected in the cultures developed for more than seven days only in the Koch’s K1 medium. The obtained data demonstrated that A. ochraceus is a good biocatalyst to introduce double bonds in the lupeol structure, whereas M. rouxii exhibits ability to biocatalyze oxygen insertions in that pentacyclic triterpene. Mass spectrometry was demonstrated to be an efficient analytical method to select promising biocatalysts for the compound investigated in this study. The biotransformation processes were influenced by the culture medium and incubation period. The obtained results open the perspective of using A. ochraceus and M. rouxii in pentacyclic triterpene biotransformations.
In the past two decades, culture has been the object of study for purposes of understanding organizational environment. Several contexts are examined in order to understand this variable which, coming from anthropology by way of the observation of social groups in different geographic regions, will be observed in this study as il variable belonging to a specific social group: The Organization. This study carries out a comparative analysis of five typologies of organizational culture, examining their similarities and diiïerenees. The typologies compared are those of Schneider (1996), Handy (1978, Quinn and McGrath (1985), Trompenaars (1994). and Hofstede (1991). The method of researeh is exploratory. Toward the end of the article, a model is proposed that incorporates the typologies referred to in the existing bibliography. What is proposed in this model is intended to assist in the determination of paradigmatic worldviews for the analysis of organizational culture by virtue of broad similarities across existing cultural variables and dimensions.
RESUMEN.A lo largo de las últimas dos décadas, la cultura ha sido objeto de estudio con el propósito de comprender mejor el entorno organizacional.
Resumo O capitalismo consciente (CC), estruturado por John Mackey e Raj Sisodia Sisodia, tem base nos princípios do propósito maior, da integração dos stakeholders, da liderança consciente e da cultura e gestão consciente, entendendo que o capitalismo pode ser uma força tanto para a economia e para o bem-estar social quanto para o meio ambiente. Nesse contexto, o objetivo do estudo foi identificar e analisar o conteúdo postado e as interações acerca do tema CC nos grupos da rede social LinkedIn. A pesquisa se caracteriza como qualitativa quanto à abordagem, exploratória e descritiva quanto aos objetivos e netnográfica quanto aos procedimentos, com observação em grupos do LinkedIn. Para realizá-la foi utilizado o modelo de fluxo simplificado de um projeto de investigação netnográfica de Kozinets (2010). Os principais resultados apontam que: a maioria dos idealizadores dos grupos se encontra nos Estados Unidos da América (EUA), país onde o CC nasceu; os grupos foram criados com a finalidade de interagir com temas ligados ao CC; as interações nos grupos ocorrem principalmente por meio de postagens e comentários com assuntos referentes ao CC, no entanto, o número de membros de um grupo não reflete maior quantidade de interações. Por fim, a maior parte dos grupos entende o CC de acordo com a definição estabelecida por seus idealizadores, John Mackey e Raj Sisodia, porém, colocá-lo em prática nas organizações tem sido um desafio.
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