The Terminal Immunoglobulin-Like Repeats of LigA and LigB of Leptospira Enhance Their Binding to Gelatin Binding Domain of Fibronectin and Host Cells

Leptospira spp. are pathogenic spirochetes that cause the zoonotic disease leptospirosis. Leptospiral immunoglobulin (Ig)-like protein B (LigB) contributes to the binding of Leptospira to extracellular matrix proteins such as fibronectin, fibrinogen, laminin, elastin, tropoelastin and collagen. A high-affinity Fn-binding region of LigB has been localized to LigBCen2, which contains the partial 11th and full 12th Ig-like repeats (LigBCen2R) and 47 amino acids of the non-repeat region (LigBCen2NR) of LigB. In this study, the gelatin binding domain of fibronectin was shown to interact with LigBCen2R (KD = 1.91±0.40 µM). Not only LigBCen2R but also other Ig-like domains of Lig proteins including LigAVar7'-8, LigAVar10, LigAVar11, LigAVar12, LigAVar13, LigBCen7'-8, and LigBCen9 bind to GBD. Interestingly, a large gain in affinity was achieved through an avidity effect, with the terminal domains, 13th (LigA) or 12th (LigB) Ig-like repeat of Lig protein (LigAVar7'-13 and LigBCen7'-12) enhancing binding affinity approximately 51 and 28 fold, respectively, compared to recombinant proteins without this terminal repeat. In addition, the inhibited effect on MDCKs cells can also be promoted by Lig proteins with terminal domains, but these two domains are not required for gelatin binding domain binding and cell adhesion. Interestingly, Lig proteins with the terminal domains could form compact structures with a round shape mediated by multidomain interaction. This is the first report about the interaction of gelatin binding domain of Fn and Lig proteins and provides an example of Lig-gelatin binding domain binding mediating bacterial-host interaction

Nano-Opto-Electro-Mechanical Systems

A new class of hybrid systems that couple optical, electrical and mechanical degrees of freedom in nanoscale devices is under development in laboratories worldwide. These nano-opto-electro-mechanical systems (NOEMS) offer unprecedented opportunities to dynamically control the flow of light in nanophotonic structures, at high speed and low power consumption. Drawing on conceptual and technological advances from cavity optomechanics, they also bear the potential for highly efficient, low-noise transducers between microwave and optical signals, both in the classical and quantum domains. This Progress Article discusses the fundamental physical limits of NOEMS, reviews the recent progress in their implementation, and suggests potential avenues for further developments in this field.Comment: 27 pages, 3 figures, 2 boxe

Chromatin and epigenetics: current biophysical views

Recent advances in high-throughput sequencing experiments and their theoretical descriptions have determined fast dynamics of the "chromatin and epigenetics" field, with new concepts appearing at high rate. This field includes but is not limited to the study of DNA-protein-RNA interactions, chromatin packing properties at different scales, regulation of gene expression and protein trafficking in the cell nucleus, binding site search in the crowded chromatin environment and modulation of physical interactions by covalent chemical modifications of the binding partners. The current special issue does not pretend for the full coverage of the field, but it rather aims to capture its development and provide a snapshot of the most recent concepts and approaches. Eighteen open-access articles comprising this issue provide a delicate balance between current theoretical and experimental biophysical approaches to uncover chromatin structure and understand epigenetic regulation, allowing free flow of new ideas and preliminary results

Associativismo, participação e cultura cívica: O potencial dos conselhos de saúde Associativism, participacion, civic culture and health councils in Brazil

No Brasil, a democratização e a descentralização abriram espaço para inúmeras experiências de participação popular em arenas de decisão de políticas públicas. O setor saúde se destaca no país e na América Latina pelo funcionamento de mais de 5.500 conselhos de saúde, nos quais a representação da sociedade civil organizada é compartilhada de forma paritária com autoridades setoriais, prestadores profissionais e institucionais e trabalhadores do setor. Este trabalho apresenta resultados de pesquisa que buscou traçar um perfil sociopolítico dos representantes dos usuários nos conselhos de saúde do Estado do Rio de Janeiro. A exposição aborda elementos teóricos relativos a temas como democracia, associativismo e cultura cívica, examina a democratização brasileira, a reforma do sistema de saúde e os conselhos de saúde, e analisa os dados da investigação. Entre as considerações finais, postula-se que a participação nos conselhos de saúde fomenta um círculo virtuoso caracterizado pelo envolvimento dos cidadãos em questões de interesse geral, pela acumulação de capital social e pelo despertar de uma cultura cívica, contribuindo, em última instância, para o fortalecimento da democracia.<br>In Brazil, the political democratization and decentralization processes opened spaces for a number of experiences of popular participation in policy decision arenas. The health sector outstands in the country as well as in Latin America because of the existence of more than 5.500 health councils in which representatives of the civil society organizations share half of the seats with those of health authorities, professional and institutional providers of health care, and of health workers. The purpose of this article is to present the main results of research endured to design a sociopolitical profile of the users' representatives in the health councils. The contents focuses on some theoretical issues concerning democracy, associativism and civic culture; examines aspects of the Brazilian democratization process, the health system reform and the health councils and, analyses the research data. Among other conclusions, it is postulated that participation of representatives of civil society in the health councils fosters a virtuous circle characterized by the involvement of citizens in matters of common good, the accumulation of social capital, and the awakening of civic culture values, thus contributing for the strengthening of democracy

Trend of leprosy in individuals under the age of 15 in Mato Grosso (Brazil), 2001-2013

OBJETIVO Identificar a tendência histórica dos indicadores epidemiológicos de hanseníase em menores de 15 anos no estado de Mato Grosso. MÉTODOS Estudo descritivo com análise de tendência dos indicadores de hanseníase em menores de 15 anos registrados no Sistema Nacional de Agravos de Notificação de Mato Grosso, no período de 2001 a 2013. Utilizou-se o procedimento de Prais-Winsten para análise de regressão linear generalizada, adotando-se nível de significância de 5%. Consideraram-se como série temporal crescente quando a annual percent change era positiva, decrescente quando negativa e estacionária quando não havia diferença significante entre seu valor e o zero. RESULTADOS Foram analisados 2.455 casos de hanseníase e o coeficiente médio de incidência em menores de 15 anos foi de 22,7/100 mil habitantes. A tendência geral do coeficiente de incidência foi decrescente, com uma annual percent change de -5,5% (IC95% -7,5–3,5). Observou-se tendência de crescimento, com incremento de 6,7% (IC95% 2,7–10,8) na proporção dos casos multibacilares, de 9,4% (IC95% 4,4–14,7) nos casos com forma clínica dimorfa e de 14% (IC95% 7,9–20,4) nos casos com incapacidade física grau 2 no momento do diagnóstico da doença. Verificou-se crescimento na proporção dos contatos de casos novos examinados, com incremento de 4,1% (IC95% 1,2–7,1) e média da proporção de cura considerada precária (39,7%) com tendência estacionária. CONCLUSÕES A tendência histórica dos casos de hanseníase em menores de 15 anos mostrou-se decrescente no período. Entretanto, as tendências dos indicadores epidemiológicos, como a proporção de casos multibacilares, de incapacidade física grau 2 e de cura, indicam o diagnóstico tardio com permanência de fontes de transmissibilidade e consequente agravo da endemia no estado de Mato Grosso.OBJECTIVE To identify the historical trend of leprosy epidemiological indicators in individuals under the age of 15 in the state of Mato Grosso. METHODS Descriptive study with trend analysis of leprosy indicators in individuals under the age of fifteen registered in the Mato Grosso’s System for Notifiable Diseases between 2001 and 2013. We used the Prais-Winsten procedure for analyzing generalized linear regression at a significance level of 5%. We considered as increasing time series when the annual percent change was positive, decreasing when negative and stationary when there was no significant difference between its value and zero. RESULTS We analyzed 2455 cases of leprosy and the average detection rate in individuals under the age of fifteen was 22.7 per 100 thousand inhabitants. The trend of the general coefficient of incidence was decreasing, with an average annual rate of -5.5% (95%CI -7.5–-3.5). Increasing trend was observed with an increase of 6.7% (95%CI 2.7–10.8) in the proportion of multibacillary cases, 9.4% (95%CI 4.4–14.7) of cases diagnosed with dimorphic clinical form and 14% (95%CI 7.9–20.4) of cases with physical disability level 2 at the time of diagnosis. There was an increasing trend in the average proportion of examined contacts, with a growth of 4.1% (95%CI 1.2–7.1) and average proportion of healing was precarious (39.7%), with stationary trend. CONCLUSIONS The historical trend of leprosy cases in individuals under the age of fifteen proved to be decreasing in the period, however the trends of epidemiological indicators such as the proportion of multibacillary cases, physical disability level 2 and healing, indicate late diagnosis with stay sources of transmission and consequent worsening of the disease in the state of Mato Grosso