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The concern regarding the harm caused by biocides to human health has been increasing over the years, making the natural products an alternative to less toxic and more efficient biocides. Therefore, this paper reports the investigation of the disinfectant potential of extracts and isolated compounds from Baccharis dracunculifolia. For this purpose, extracts of aerial parts (BD-C), tricomial wash (BD-L) and roots (BD-R) of B. dracunculifolia were obtained by maceration. The extracts were submitted to different chromatographic techniques, including high-speedy countercurrent chromatography (HSCCC) furnishing nine isolated compounds. The extracts and isolated compounds were evaluated regarding their antimicrobial activity by the broth microdilution method, according to the Clinical and Laboratory Standards Institute, and regarding their sanitizing activity according to Standard Operating Procedure No. 65·3210·007 (INCQS, 2011), developed by the National Institute for Quality Control in Health (INCQS) - Oswaldo Cruz Foundation (FIOCRUZ). In the antimicrobial evaluation the BD-C extract showed minimum inhibitory concentration (MIC) values of 200 and 100 µg/ml against Staphylococcus aureus and Tricophyton mentagrophytes, respectively. BD-L extract showed MIC value of 200 µg/ml against S. aureus. The isolated compounds caffeic acid (MBC 2·22 µmol l-1 ), ferulic acid (MBC 2·06 µmol l-1 ) and baccharin (MBC 0·27 µmol l-1 ) showed significant inhibitory activity against S. aureus. All B. dracunculifolia isolated compounds were active with exception of aromadrendin-4´-O-methyl-ether for T. mentagrophytes. Additionally, isosakuranetin was active against Salmonella choleraesuis (MIC 1·4 µmol l-1 ). Regarding the sanitizing activity, the hydroalcoholic solution containing 0·2% of B. dracunculifolia extract in 40°GL ethanol was effective in eliminating the microbial contamination on all carrier cylinders and against all microorganisms evaluated in the recommended exposure time of 10 min. Therefore, B. dracunculifolia has potential for the development of sanitizing agents to be used in hospitals, food manufactures and homes.

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This study investigated the osteogenic performance of new brushite cements obtained from Li+-doped ß-tricalcium phosphate as a promising strategy for bone regeneration. Lithium (Li+) is a promising trace element to encourage the migration and proliferation of adipose-derived stem cells (hASCs) and the osteogenic differentiation-related gene expression, essential for osteogenesis. In-situ X-ray diffraction (XRD) and in-situ 1H nuclear magnetic resonance (1H NMR) measurements proved the precipitation of brushite, as main phase, and monetite, indicating that Li+ favored the formation of monetite under certain conditions. Li+ was detected in the remaining pore solution in significant amounts after the completion of hydration. Isothermal calorimetry results showed an accelerating effect of Li+, especially for low concentration of the setting retarder (phytic acid). A decrease of initial and final setting times with increasing amount of Li+ was detected and setting times could be well adjusted by varying the setting retarder concentration. The cements presented compressive mechanical strength within the ranges reported for cancellous bone. In vitro assays using hASCs showed normal metabolic and proliferative levels. The immunodetection and gene expression profile of osteogenic-related markers highlight the incorporation of Li+ for increasing the in vivo bone density. The osteogenic potential of Li-doped brushite cements may be recommended for further research on bone defect repair strategies.

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In the present study, we demonstrated the in vitro activity of endophytic phosphate-solubilizing bacteria (PSB). Fifty-five endophytic PSB that were isolated from sap, leaves, and roots of maize were tested for their ability to solubilize tricalcium phosphate and produce organic acid. Partial sequencing of the 16S rRNA-encoding gene showed that the isolates were from the genus Bacillus and different species of Enterobacteriaceae. The phosphate solubilization index on solid medium and phosphate solubilization in liquid medium varied significantly among the isolates. There was a statistically significant difference (P ≤ 0.05) for both, the values of phosphate-solubilizing activity and pH of the growth medium, among the isolates. Pearson correlation was statistically significant (P ≤ 0.05) between P-solubilization and pH (R = -0.38), and between the gluconic acid production and the lowering of the pH of the liquid medium at 6 (R = 0.28) and 9 days (R = 0.39). Gluconic acid production was prevalent in all the PSB studied, and Bacillus species were most efficient in solubilizing phosphate. This is the first report on the characterization of bacterial endophytes from maize and their use as potential biofertilizers. In addition, this may provide an alternative strategy for improving the phosphorus acquisition efficiency of crop plants in tropical soils.

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Charcot-Marie-Tooth type 1A disease (CMT1A) is most frequently caused by a tandem DNA duplication of a 1.4-Mb genomic fragment in the 17p11.2-12 chromosomal region. The disease is probably the product of a dosage effect of the peripheral myelin protein 22 gene located within the duplicated segment. We sought to study the largest reported Brazilian family with suspected diagnosis of CMT1A using eight short tandem repeat microsatellite markers. In addition, we analyzed the informativeness of these markers in the normal Brazilian population. The duplication was found in 12 members of the family. In two patients with CMT1A symptoms, the duplication was not detected, and one asymptomatic subject showed the duplication. D17S2230, D17S9B, D17S2220, D17S2227, D17S9A, and D17S4A markers showed the highest heterozygosity rates, and D17S2228 and D17S2224 markers were the least informative in our analysis.

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