Análise integrada de sistemas de produção de tomateiro com base em indicadores edafobiológicos.

A análise integrada de indicadores edafobiológicos ligados ao manejo do solo constitui uma ferramenta importante para estimar níveis de sustentabilidade do agroecossistema, detectando-se pontos críticos para a devida correção de manejo. Essa ferramenta foi empregada na avaliação de sistemas de produção orgânica e convencional de tomate, em cultivo protegido e a campo aberto, no estado de São Paulo. Tomaram-se como referência solos de mata nativa e/ou pastagem natural, dependendo do local de estudo. Em Serra Negra, o solo sob sistema orgânico apresentou maior capacidade de campo e teor de argila dispersa mais baixo, indicativos da estabilidade dos agregados. No sistema convencional observou-se uma elevada condutividade elétrica, evidenciando a alta disponibilidade de sais solúveis. A análise de componentes principais (ACP) permitiu concluir que há maior grau de similaridade entre o solo sob sistema orgânico e aqueles das bases referenciais, com respeito aos indicadores químicos e biológicos. Constatou-se que C org, N total, polissacarídeos, FDA (hidrólise de diacetato de fluoresceína) e atividade enzimática de desidrogenase estão positivamente relacionados com o sistema orgânico, a mata nativa e a pastagem. Em contrapartida, a saturação por bases (V%), pH, teores de Mn, Mg e Ca, bem como a razão de dispersão estão inversamente relacionadas ao manejo orgânico. Já em Araraquara, os resultados da ACP distinguiram as áreas organicamente cultivadas das matas nativas, principalmente, com base nos indicadores biológicos

Rectal Transmission of Transmitted/Founder HIV-1 Is Efficiently Prevented by Topical 1% Tenofovir in BLT Humanized Mice

Rectal microbicides are being developed to prevent new HIV infections in both men and women. We focused our in vivo preclinical efficacy study on rectally-applied tenofovir. BLT humanized mice (n = 43) were rectally inoculated with either the primary isolate HIV-1(JRCSF) or the MSM-derived transmitted/founder (T/F) virus HIV-1(THRO) within 30 minutes following treatment with topical 1% tenofovir or vehicle. Under our experimental conditions, in the absence of drug treatment we observed 50% and 60% rectal transmission by HIV-1(JRCSF) and HIV-1(THRO), respectively. Topical tenofovir reduced rectal transmission to 8% (1/12; log rank p = 0.03) for HIV-1(JRCSF) and 0% (0/6; log rank p = 0.02) for HIV-1(THRO). This is the first demonstration that any human T/F HIV-1 rectally infects humanized mice and that transmission of the T/F virus can be efficiently blocked by rectally applied 1% tenofovir. These results obtained in BLT mice, along with recent ex vivo, Phase 1 trial and non-human primate reports, provide a critically important step forward in the development of tenofovir-based rectal microbicides

Risk of cancer in patients on insulin glargine and other insulin analogues in comparison with those on human insulin

Aims/hypothesis Several publications suggest an association between certain types of insulin and cancer, but with conflicting results. We investigated whether insulin glargine (A21Gly,B31Arg,B32Arg human insulin) is associated with an increased risk of cancer in a large population-based cohort study. Methods Data for this study were obtained from dispensing records from community pharmacies individually linked to hospital discharge records from 2.5 million individuals in the Netherlands. In a cohort of incident users of insulin, the association between insulin glargine and other insulin analogues, respectively, and cancer was analysed in comparison with human insulin using Cox proportional hazard models with cumulative duration of drug use as a time-varying determinant. The first hospital admission with a primary diagnosis of cancer was considered as the main outcome; secondary analyses were performed with specific cancers as outcomes. Results Of the 19,337 incident insulin users enrolled, 878 developed cancer. Use of insulin glargine was associated with a lower risk of malignancies in general in comparison with human insulin (HR 0.75, 95% CI 0.71, 0.80). In contrast, an increased risk was found for breast cancer (HR 1.58, 95% CI 1.22, 2.05). Dose-response relationships could not be identified. Conclusion/interpretation Users of insulin glargine and users of other insulin analogues had a lower risk of cancer in general than those using human insulin. Both associations might be a consequence of residual confounding, lack of adherence or competing risk. However, as in previous studies, we demonstrated an increased risk of breast cancer in users of insulin glargine in comparison with users of human insulin

Scoping review on vector-borne diseases in urban areas : transmission dynamics, vectorial capacity and co-infection

BACKGROUND: Transmission dynamics, vectorial capacity, and co-infections have substantial impacts on vector-borne diseases (VBDs) affecting urban and suburban populations. Reviewing key factors can provide insight into priority research areas and offer suggestions for potential interventions. MAIN BODY: Through a scoping review, we identify knowledge gaps on transmission dynamics, vectorial capacity, and co-infections regarding VBDs in urban areas. Peer-reviewed and grey literature published between 2000 and 2016 was searched. We screened abstracts and full texts to select studies. Using an extraction grid, we retrieved general data, results, lessons learned and recommendations, future research avenues, and practice implications. We classified studies by VBD and country/continent and identified relevant knowledge gaps. Of 773 articles selected for full-text screening, 50 were included in the review: 23 based on research in the Americas, 15 in Asia, 10 in Africa, and one each in Europe and Australia. The largest body of evidence concerning VBD epidemiology in urban areas concerned dengue and malaria. Other arboviruses covered included chikungunya and West Nile virus, other parasitic diseases such as leishmaniasis and trypanosomiasis, and bacterial rickettsiosis and plague. Most articles retrieved in our review combined transmission dynamics and vectorial capacity; only two combined transmission dynamics and co-infection. The review identified significant knowledge gaps on the role of asymptomatic individuals, the effects of co-infection and other host factors, and the impacts of climatic, environmental, and socioeconomic factors on VBD transmission in urban areas. Limitations included the trade-off from narrowing the search strategy (missing out on classical modelling studies), a lack of studies on co-infections, most studies being only descriptive, and few offering concrete public health recommendations. More research is needed on transmission risk in homes and workplaces, given increasingly dynamic and mobile populations. The lack of studies on co-infection hampers monitoring of infections transmitted by the same vector. CONCLUSIONS: Strengthening VBD surveillance and control, particularly in asymptomatic cases and mobile populations, as well as using early warning tools to predict increasing transmission, were key strategies identified for public health policy and practice

Long-term clinical, immunologic and virologic impact of glucocorticoids on the chronic phase of HIV infection

BACKGROUND: To test the hypothesis of down-regulating the increased immune system activation/destruction process associated with chronic HIV infection, we focused our interest on prednisolone (PDN), because we had showed that, in vitro, PDN had a strong anti-apoptotic activity on activated T cells of HIV-infected patients and no effect on viral replication. We thus designed in 1992 a pilot study to evaluate the clinical, immunologic and virologic effects of PDN. The drug was given to a group of 44 patients with CD4 T cells over 200/μl. After one year, no patient had developed clinical AIDS and the mean CD4 T cell count of the group had increased from 441 ± 21 cells/μl to 553 ± 43 cells/μl. Moreover, markers of immune activation had dropped back to normal levels while the mean viral load of the group had remained unchanged. Here we explore the long-term clinical, immunologic, and virologic impact of prednisolone on the chronic phase of HIV infection. METHODS: Retrospective study over 10 years starting between July 1992 and February 1993. A total of 44 patients with CD4 cells/μl ranging from 207 to 775 were treated with prednisolone, 0.5 mg/kg/d, over 6 months and 0.3 mg/kg/d thereafter. RESULTS: No clinical AIDS developed under prednisolone; side effects of the drug were mild. CD4 cells which increased from 421 cells/μl at entry to 625 cells/μl at day 15, slowly decreased to reach 426 cells/μl after two years; T cell apoptosis and activation markers dropped within 15 days to normal levels and reincreased slowly thereafter. Serum viral loads remained stable. The percentage of patients maintaining CD4 cells over entry was 43.2% at two years, 11.4% at five years and 4.6% at 10 years. Initial viral load was highly predictive of the rate of CD4 decrease under prednisolone. CONCLUSIONS: Prednisolone postponed CD4 cell decrease in a viral load dependent manner for a median of two years and for up to 10 years in a fraction of the patients with a low viral load. These findings might stimulate clinical trials as well as biological research on the role of antiapoptotic drugs in HIV infection

The Evolving Landscape of the Economics of HIV Treatment and Prevention

Bohdan Nosyk and Julio Montaner argue that the cost-effectiveness of HAART roll out has been significantly underestimated because economic analyses haven't yet taken into account the beneficial impact of HAART on HIV transmission

Protective effect of Arque-Ajeeb on acute experimental diarrhoea in rats

BACKGROUND: Diarrhoea is a major health problem for children worldwide, accounting for 5–8 million deaths each year. Arque-Ajeeb (AA) is a compound formulation of Unani medicine. It is reputed for its beneficial effects in the treatment of diarrhoea and cholera, but the claim of its efficacy is yet to be tested. Therefore the present study has been planned to investigate the real efficacy of this drug in rats. METHODS: The effect of Arque-Ajeeb was investigated for antidiarrhoeal activity against charcoal-induced gut transit, serotonin-induced diarrhoea and PGE(2)-induced small intestine enteropooling in rats. The control, standard and test groups of experimental animals were administered with normal saline (p.o.), diphenoxylate hydrochloride (5 mg/kg, p.o.) and Arque-Ajeeb (0.07 ml and 0.14 ml/kg, p.o.) respectively except the control group of PGE(2)-induced small intestine enteropooling which received only 5% ethanol in normal saline (i.p.). Charcoal (10 ml/kg, p.o.) and serotonin (600 μg/kg, i.p.) were administered after 30 min, while PGE(2 )(100 μg/kg, p.o.) was administered immediately afterwards. The distance traveled by charcoal in small intestine was measured after 15 and 30 min of charcoal administration, diarrhoea was observed every 30-min for six hour after serotonin administration and the volume of intestinal fluid was measured after 30 min of PGE(2 )administration. RESULTS: Arque-Ajeeb (0.07 ml and 0.14 ml/kg) significantly inhibited the frequency of defaecation and decreased the propulsion of charcoal meal through the gastrointestinal tract, reduced the wetness of faecal droppings in serotonin-induced diarrhoea and also reduced the PGE(2)-induced small intestine enteropooling. CONCLUSION: Arque-Ajeeb may have potential to reduce the diarrhoea in rats. Thus the drug may prove to be an alternate remedy in diarrhoea