Incorporation of Nitroprusside on Silica Nanoparticles-A Strategy for Safer Use of This NO Donor in Therapy.

Silica-based nanoparticles have been developed as powerful platforms for drug delivery and might also prevent undesired side effects of drugs. Here, a fast method to synthesize positively charged mesoporous silica nanoparticles (ζ = 20 ± 0.5 mV, surface area = 678 m2 g-1, and 2.3 nm of porous size) was reported. This nanomaterial was employed to anchor sodium nitroprusside (SNP), a vasodilator drug with undesired cyanide release. A remarkable incorporation of 323.9 ± 7.55 µmol of SNP per gram of nanoparticle was achieved, and a series of studies of NO release were conducted, showing efficient release of NO along with major cyanide retention (ca. 64% bound to nanoparticle). Biological assays with mammalian cells showed only a slight drop in cell viability (13%) at the highest concentration (1000 µM), while SNP exhibited an LC50 of 228 µM. Moreover, pharmacological studies demonstrated similar efficacy for vasodilation and sGC-PKG-VASP pathway activation when compared to SNP alone. Altogether, this new SNP silica nanoparticle has great potential as an alternative for wider and safer use of SNP in medicine with lower cyanide toxicity.

Prevalence of hypertension and its associated factors in contaminated areas of the Santos-São Vicente Estuarine region and Bertioga, Brazil: 2006-2009.

In Brazil, cardiovascular diseases account for 33% of deaths and the prevalence of hypertension is of approximately 22%. The Santos and São Vicente Estuarine System is the most important example of environmental degradation by chemicals from industrial sources. The aim of the present study was to evaluate the prevalence of hypertension and its associated factors in the population of this estuary in the period 2006-2009. A cross-sectional study was conducted to assess the aforementioned prevalence of hypertension in the evaluated areas, as well as risk factors for this disease in four contaminated areas located in the Estuary, and one area outside Estuary, the city of Bertioga. Associations between categorical variables were tested using Pearson's chi-square test incorporating Yates' correction, or Fisher's exact test. Single and multiple logistic regression models were applied to evaluate the risk factors for hypertension. The highest prevalence of hypertension was found in Continental São Vicente (28.4%). The risk factors for hypertension were the following: living in Center of Cubatão (OR: 1.3; IC95%: 1.0 - 1.6) and Continental São Vicente (OR: 1.4; IC95%: 1.1 - 1.8); illiterate (OR: 1.9; IC95%: 1.1 - 3.2); living in the area for more than 20 years (OR: 1.2; IC95%: 1.0 - 1.5); group of people aged 36-60 years (OR: 3.9; IC95%: 3.3 - 4.6) and who have had past occupational exposure (OR: 1.3; IC95%: 1.1 - 1.6). Results indicate that living in contaminated areas, especially for a longer time, is a risk factor for hypertension.

Evidences of antihypertensive potential of extract from Solanum capsicoides All. in spontaneously hypertensive rats.

BACKGROUND: Solanum capsicoides All. is morphologically similar to Solanum sisymbriifolium Lam. which is used in folk medicine in South America for antihypertensive and diuretics purposes. This similarity has led to species identification errors, which therefore may result in errors by patients. PURPOSE: To evaluate the antihypertensive and diuretics potential of the methanol extract from Solanum capsicoides All. (MeOH-Sc), in vitro and in vivo, in spontaneously hypertensive rats (SHR). METHODS: Initial experiments were performed in rat mesenteric artery to evaluate the in vitro vascular effect of MeOH-Sc and its fractions, in addition to the mechanisms involved during the observed effect. Mean arterial pressure (MAP) and heart rate (HR) were recorded in non-anesthetised hypertensive and normotensive rats. In another set of experiments, MeOH-Sc was administered for 21 consecutive days. Daily body weight measurements were conducted and MAP, HR and urinary volume were measured every 5 days. The mesenteric artery from treated animals was tested for phenylephrine and sodium nitroprussiate (SNP) sensitivity. RESULTS: Initially, MeOH-Sc and fractions relaxed phenylephrine-induced contractions in mesenteric artery rings. The vasorelaxant effect was not changed in the presence of a blocker of eNOS (L-NAME) in rings with an intact endothelium. In denuded-endothelium rings, the vasorelaxant response was significantly reduced in the presence of a cAMP inhibitor (SQ 22536 10 µM) in SHR but not in Wistar Kyoto rats (WKY). However, in the presence of a cGMP inhibitor (ODQ 10 µM), a curve shift to the right was observed in WKY animals, but not in SHR. Intravenous bolus injections of MeOH-Sc into non-anesthetised SHR and WKY, induced hypotension that was associated with an increase in HR. A significant antihypertensive effect was observed in animals that received MeOH-Sc orally for 21 days, which also prevented the development of cardiac hypertrophy. Urine volume from animals treated with MeOH-Sc significantly increased. Finally, MeOH-Sc induced beneficial changes in vascular responsiveness. CONCLUSION: MeOH-Sc has a potential antihypertensive effect in SHR.

Prevalence of liver diseases as referred by people living in the Santos and São Vicente Estuary.

The Santos and São Vicente Estuary has suffered extensively over the years from irregular industrial deposits. The present study aimed to evaluate liver disease prevalence and potential associated risk factors in four of the Estuary's areas (Pilões and Água-Fria, Cubatão Center, Continental São Vicente, and Guarujá) and a reference area (Bertioga). This study consisted of a cross-sectional study design, in which a questionnaire was used to collect information in 820 households at each of the study areas. The proportion of total liver diseases, hepatitis, cirrhosis, and cancer (liver, biliary tract, and pancreas) per area were estimated. Pearson's chi-square test and two proportion differences test were applied in order to evaluate associations between disease occurrence and areas and to test differences between two proportions, respectively. Single and multiple logistic regression models were applied to assess associations between disease prevalence and the different study areas. Liver disease prevalence was 1.5 % among all inhabitants and 1.4 % among those without any type of exposure. Among those who reported the presence of liver disease, a higher percentage of the participants that reported hepatitis (27.7 %) or other liver disease (48.7 %) did not report occupational or alcohol exposures. Hepatitis (77.8 %) was the most reported disease, and a statistical association between living in Pilões and Água-Fria and the occurrence of hepatitis was observed (Pearson's χ (2): z = 18.1; p = 0.001). The consumption of locally-produced groceries (2.88; CI: 1.24-6.70) and water (5.88; CI: 2.24-15.45) were shown to be risk factors for the occurrence of liver disease. Thus, environmental exposure is still a public health problem present in the estuary region.