Improving pandemic influenza risk assessment

10.7554/eLife.03883eLife3e0388

Stock indexing and Potato virus Y elimination from potato plants cultivated in vitro Indexação de matrizes e eliminação do Potato virus Y em plantas de batata cultivadas in vitro

Potato cultivars (Solanum tuberosum L.) have shown degeneration or run out caused by viruses after several cycles of propagation using seed tubers from commercial fields. This work reports the occurrence of single and mixed infections of four potato viruses in Paraíba-Brazil and presents a method for Potato virus Y (PVY) elimination, by using thermo-and chemotherapies. Plants of potato cv. Baraka were tested by direct antigen coating ELISA. Antisera against PVY, Potato virus X (PVX), Potato virus S (PVS), and Potato leafroll virus (PLRV) were used. Materials with positive reaction to PVY were treated for virus elimination. Single node cuttings (1.0 cm length) were excised and inoculated in Murashige & Skoog (MS) medium, supplemented with 1.0 mg L-1 of kinetin, 0.001 mg L-1 of naphthalene acetic acid (NAA) and 0.1 mg L-1 of gibberellic acid (GA3). The thermotherapy at approximately 37ºC, during 30 and 40 days, resulted in 20.0 and 37.5% PVY elimination, respectively. Chemotherapy was undertaken with Ribavirin (RBV), 5-Azacytidine (AZA), and 3-Deazauridine (DZD). The RBV showed the highest rate of virus eradication, with 55.5% virus-free plants. Simultaneous thermo and chemotherapy had higher efficiency for the elimination of PVY, reaching rates of healthy plants of 83.3% with RBV, 70.0% with AZA, and 50.0% with DZD.<br>Cultivares de batata (Solanum tuberosum L.) têm mostrado degenerescência causada por vírus após ciclos sucessivos do uso de tubérculos de campos comerciais como material propagativo. Este trabalho verifica a ocorrência de infecção simples e mista de quatro vírus da batata na Paraíba e apresenta adequação da técnica de cultivo in vitro para obtenção de material livre de Potato virus Y (PVY), incluindo uso de microestacas, termo e quimioterapia. Plantas de batata do cv. Baraka foram submetidas à indexação sorológica pelo teste "direct antigen coating" ELISA. Utilizaram-se antissoros contra o PVY, Potato virus X (PVX), Potato virus S (PVS) e Potato leafroll virus (PLRV). Materiais com reação positiva para PVY foram submetidos a tratamentos visando à eliminação viral. Microestacas (1,0 cm de comprimento) com uma gema foram excisadas e inoculadas em meio nutritivo de Murashige & Skoog (MS), suplementado com 1,0 mg L-1 de cinectina, 0,00l mg L-1 de ácido naftaleno acético (ANA) e 0,1 mg L-1 de ácido giberélico (GA3). Termoterapia a 37ºC, durante 30 e 40 dias, promoveu a eliminação do PVY em 20,0 e 37,5% no material testado, respectivamente. A quimioterapia foi realizada com Ribavirin (RBV), 5-Azacitidina (AZA) e 3-Deazauridine (DZD). O RBV apresentou os melhores índices de erradicação de vírus com a obtenção de 55,5% de plantas sadias. Tratamentos simultâneos de termo e quimioterapia mostraram maior eficiência na eliminação viral, atingindo um percentual de plantas sadias da ordem de 83,3 com RBV, 70,0 com AZA e 50,0 com DZD

Social inequalities in health related behaviours in Barcelona

OBJECTIVE—This study describes social class inequalities in health related behaviours (tobacco and alcohol consumption, physical activity) among a sample of general population over 14 years old in Barcelona.
DESIGN—Cross sectional study (Barcelona Health Interview Survey).
SETTING—Barcelona city (Spain).
PARTICIPANTS—A representative stratified sample of the non-institutionalised population resident in Barcelona was obtained. This study refers to the 4171 respondents aged over 14.
DATA—Social class was obtained from a Spanish adaptation of the British Registrar General classification. In addition, sociodemographic variables such as family structure and employment status were used. As health related behaviours tobacco consumption, alcohol consumption, usual physical activity and leisure time physical activity were analysed. Age adjusted percentages were compared by social class. Multivariate analysis was performed using logistic regression models.
MAIN RESULTS—Women in the upper social classes were more likely to smoke, the adjusted odds ratio (OR) for social class V in reference to social class I was 0.36 (95% confidence intervals (95%CI): 0.19, 0.67), while the opposite occurred among men although it was not statistically significant in multivariate analysis. Smoking cessation was more likely among men in the higher classes (OR for class V 0.41, 95%CI: 0.18, 0.90). Excessive alcohol consumption among men showed no differences between classes, while among women it was greater in the upper classes. Engaging in usual physical activity classified as "light or none" in men decreased with lowering social class (OR class IVa: 0.55 and OR class IVb: 0.47). Women of social classes IV and V were less likely to have two or more health risk behaviours (OR for class V 0.33, 95% CI: 0.18, 0.62).
CONCLUSION—Health damaging behaviours are differentially distributed among social classes in Barcelona. Health policies should take into account these inequalities.


Keywords: health related behaviours; social class; health surve