Chemical composition and evaluation of modulatory of the antibiotic activity from extract and essential oil of Myracrodruon urundeuva

Context: The combination of antibiotics with natural products has demonstrated promising synergistic effects in several therapeutic studies.

Objective: The aim of this study was to determine the effect of a combination of an ethanol extract of Myracrodruon urundeuva Fr. All. (Anacardiaceae) (aroeira plant) and its essential oil with six antimicrobial drugs against multiresistant strains of Staphylococcus aureus and Escherichia coli from clinical isolates.

Materials and methods: After identification of the chemical components by GC-MS, the antibacterial activity of the natural products and antibiotics was assessed by determining the minimal inhibitory concentration (MIC) using the microdilution method and concentrations ranging 8–512?μg/mL and 0.0012–2.5?mg/mL, respectively. Assays were performed to test for a possible synergistic action between the plant products and the antimicrobials, using the extract and the oil at a sub-inhibitory concentration (128?μg/mL) and antibiotic at concentrations varying between 8 and 512?μg/mL.

Results: The GC-MS analysis identified the main compound as δ-carene (80.41%). The MIC of the natural products was >1024?μg/mL, except against S. aureus ATCC25923. Only the combinations of the natural products with gentamicin, amikacin and clindamycin were effective against S. aureus 358, enhancing the antibiotic activity by reducing the MIC.

Conclusions: The extract from aroeira showed a higher antibacterial activity and the oil was more effective in potentiating the activity of conventional antibiotics.     

HIV Prevalence,Knowledge, Attitudes,and Practices Among Polydrug Users in Brazil: A Biological Survey Using Respondent Driven Sampling

Brazil has a concentrated HIV epidemic among key populations. In 2009, the Ministry of Health conducted a survey in 10 Brazilian cities aiming to estimate HIV prevalence, knowledge, and associated risk behaviors of polysubstance users (PSU). Using Respondent Driven Sampling (RDS), 3449 PSU were recruited, answered an Audio-Computer Self Assisted Interview (ACASI) and were tested for HIV and syphilis. Analyses were weighted by individual’s social network size generated on RDSAT. Pooled HIV prevalence was 5.8% but varied across cities. Most PSU were male, non-white, without income, unemployed, with low levels of education. Overall, 12.0% used injectable drugs, 48.7% had sex with occasional partners and 46.4% engaged in commercial sex. A majority received free condoms (71.4%) but 76.7% exhibited inconsistent condom use. Findings can support policies aiming to improve health care and preventive interventions tailored to this population that remains at high risk of acquiring and transmitting HIV/STI in multiple scenarios.     

A new nanoemulsion formulation improves antileishmanial activity and reduces toxicity of amphotericin B

This work aimed to optimise a new nanoemulsion (NE) formulation loaded with Amphotericin B (AmB) and to evaluate its in vivo antileishmanial activity and in vitro haemolytic toxicity. The influence of gradual increases in pressure, using a high-pressure homogeniser, was evaluated. The NE was characterised for droplet size, polydispersity index, zeta potential and encapsulation efficiency (EE). For antileishmanial activity studies, AmB-NE was administered intravenously in mice infected by Leishmania infantum chagasi, which causes Visceral Leishmaniasis (VL). When the NE was submitted to gradual increases in pressure, the PI values and droplet size decreased. The droplet size (～145?nm) was lower than that obtained in previous studies. The zeta potential was negative and the EE was almost 100%. The haemolytic toxicity, evaluated on human red blood cells, for AmB-loaded NE was lower than that observed for the conventional AmB (C-AmB). C-AmB at 2?mg/kg was very toxic. In contrast, administration of the AmB-loaded NE, at same dose, did not result in any sign of acute toxicity, promoting a significant reduction in parasite burden as compared to the C-AmB. These findings suggest that this new AmB-loaded NE constitutes an attractive alternative for the treatment of VL due to improved efficacy and lower toxicity.     

Home management of INR in the public health system: feasibility of self-management of oral anticoagulation and long-term performance of individual POC devices in determining INR

The home prothrombin time/international normalized ratio (PT/INR) self-management could be convenient for patients, enhancing treatment compliance and improving the quality of the oral anticoagulation. However, patient self-management (PSM) of oral anticoagulation may not be feasible for up to half of the patients due to cognitive or educational issues. In the present study, we aimed to evaluate the feasibility of a PSM program in a public health medical center that provides care for low-income patients. We also aimed to determine the accuracy of individual point-of-care devices (CoaguChek XS^®) during long-term of home manipulation. Patients’ time-in-therapeutic range (TTR) and perception of quality of life, were evaluated at scheduled study-visits to the center. Additionally, the accuracy of individual CoaguChek XS^® was evaluated in comparison to the standard automated coagulometer at scheduled study-visits to the center. Twenty-five patients were included in the PSM program. The median TTR of patients was 75 % before inclusion, 72 % at 3 months, 75 % at 6 months and 100 % at 12 months after the beginning of self-management (P = 0.14).The median DASS scores were 64, 63, 61.5 and 71.5 before inclusion and at 3, 6 and 12 months, respectively (P = 0.09). One hundred paired INR values were obtained. Correlation between INR values delivered by individual CoaguChek XS^® and the automated coagulometer was 94 % and the mean result bias was 0.07 INR units. The coefficient of correlation and the mean bias between methods was stable during 24 months of follow-up. The present study suggests that PSM is feasible for patients treated in the public health system and that the results delivered by CoaguChek XS^® have long-term reliability.