A New Extraction Approach To Correct The Effect Of Apparent Increase In The Secoiridoid Content After Filtration Of Virgin Olive Oil.

In the current study, a new approach has been developed for correcting the effect that moisture reduction after virgin olive oil (VOO) filtration exerts on the apparent increase of the secoiridoid content by using an internal standard during extraction. Firstly, two main Spanish varieties (Picual and Hojiblanca) were submitted to industrial filtration of VOOs. Afterwards, the moisture content was determined in unfiltered and filtered VOOs, and liquid-liquid extraction of phenolic compounds was performed using different internal standards. The resulting extracts were analyzed by HPLC-ESI-TOF/MS, in order to gain maximum information concerning the phenolic profiles of the samples under study. The reduction effect of filtration on the moisture content, phenolic alcohols, and flavones was confirmed at the industrial scale. Oleuropein was chosen as internal standard and, for the first time, the apparent increase of secoiridoids in filtered VOO was corrected, using a correction coefficient (Cc) calculated from the variation of internal standard area in filtered and unfiltered VOO during extraction. This approach gave the real concentration of secoiridoids in filtered VOO, and clarified the effect of the filtration step on the phenolic fraction. This finding is of great importance for future studies that seek to quantify phenolic compounds in VOOs.

Evaluation Of The Effect Of Different Methods Of Microabrasion And Polishing On Surface Roughness Of Dental Enamel.

The microabrasion technique of enamel consists of selectively abrading the discolored areas or causing superficial structural changes in a selective way. In microabrasion technique, abrasive products associated with acids are used, and the evaluation of enamel roughness after this treatment, as well as surface polishing, is necessary. This in-vitro study evaluated the enamel roughness after microabrasion, followed by different polishing techniques. Roughness analyses were performed before microabrasion (L1), after microabrasion (L2), and after polishing (L3).Thus, 60 bovine incisive teeth divided into two groups were selected (n=30): G1- 37% phosphoric acid (37%) (Dentsply) and pumice; G2- hydrochloric acid (6.6%) associated with silicon carbide (Opalustre - Ultradent). Thereafter, the groups were divided into three sub-groups (n=10), according to the system of polishing: A - Fine and superfine granulation aluminum oxide discs (SofLex 3M); B - Diamond Paste (FGM) associated with felt discs (FGM); C - Silicone tips (Enhance - Dentsply). A PROC MIXED procedure was applied after data exploratory analysis, as well as the Tukey-Kramer test (5%). No statistical differences were found between G1 and G2 groups. L2 differed statistically from L1 and showed superior amounts of roughness. Differences in the amounts of post-polishing roughness for specific groups (1A, 2B, and 1C) arose, which demonstrated less roughness in L3 and differed statistically from L2 in the polishing system. All products increased enamel roughness, and the effectiveness of the polishing systems was dependent upon the abrasive used.

Effect Of Sodium Hypochlorite And Peracetic Acid On The Surface Roughness Of Acrylic Resin Polymerized By Heated Water For Short And Long Cycles.

To evaluate the surface roughness of acrylic resin submitted to chemical disinfection via 1% sodium hypochlorite (NaClO) or 1% peracetic acid (C2H4O3). The disc-shaped resin specimens (30 mm diameter ×4 mm height) were polymerized by heated water using two cycles (short cycle: 1 h at 74°C and 30 min at 100°C; conventional long cycle: 9 h at 74°C). The release of substances by these specimens in water solution was also quantified. Specimens were fabricated, divided into four groups (n = 10) depending on the polymerization time and disinfectant. After polishing, the specimens were stored in distilled deionized water. Specimens were immersed in 1% NaClO or 1% C2H4O3 for 30 min, and then were immersed in distilled deionized water for 20 min. The release of C2H4O3 and NaClO was measured via visual colorimetric analysis. Roughness was measured before and after disinfection. Roughness data were subjected to two-way ANOVA and Tukey's test. There was no interaction between polymerization time and disinfectant in influencing the average surface roughness (Ra, P = 0.957). Considering these factors independently, there were significant differences between short and conventional long cycles (P = 0.012), but no significant difference between the disinfectants hypochlorite and C2H4O3 (P = 0.366). Visual colorimetric analysis did not detect release of substances. It was concluded that there was the difference in surface roughness between short and conventional long cycles, and disinfection at acrylic resins polymerized by heated water using a short cycle modified the properties of roughness.

Long-term Efficacy And Safety Of Tenofovir Disoproxil Fumarate In Hiv-1-infected Adolescents Failing Antiretroviral Therapy: The Final Results Of Study Gs-us-104-0321.

Reports of long-term tenofovir disoproxil fumarate (TDF) treatment in HIV-infected adolescents are limited. We present final results from the open-label (OL) TDF extension following the randomized, placebo (PBO)-controlled, double-blind phase of GS-US-104-0321 (Study 321). HIV-infected 12- to 17-year-olds treated with TDF 300 mg or PBO with an optimized background regimen (OBR) for 24-48 weeks subsequently received OL TDF plus OBR in a single arm study extension. HIV-1 RNA and safety, including bone mineral density (BMD), was assessed in all TDF recipients. Eighty-one subjects received TDF (median duration 96 weeks). No subject died or discontinued OL TDF for safety/tolerability. At week 144, proportions with HIV-1 RNA <50 copies/mL were 30.4% (7 of 23 subjects with baseline HIV-1 RNA >1000 c/mL initially randomized to TDF), 41.7% (5 of 12 subjects with HIV-1 RNA <1000 c/mL who switched PBO to TDF) and 0% (0 of 2 subjects failed randomized PBO plus OBR with HIV-1 RNA >1000 c/mL and switched PBO to TDF). Viral resistance to TDF occurred in 1 subject. At week 144, median decrease in estimated glomerular filtration rate was 38.1 mL/min/1.73 m (n = 25). Increases in median spine (+12.70%, n = 26) and total body less head BMD (+4.32%, n = 26) and height-age adjusted Z-scores (n = 21; +0.457 for spine, +0.152 for total body less head) were observed at week 144. Five of 81 subjects (6%) had persistent >4% BMD decreases from baseline. Some subjects had virologic responses to TDF plus OBR, and TDF resistance was rare. TDF was well tolerated and can be considered for treatment of HIV-infected adolescents.

Altered Urinary Sodium Excretion Response After Central Cholinergic And Adrenergic Stimulation Of Adult Spontaneously Hypertensive Rats.

In this study, we hypothesized that blunting of the natriuresis response to intracerebroventricularly (i.c.v.) microinjected cholinergic and adrenergic agonists is involved in the development of hypertension in spontaneously hypertensive rats (SHR). We evaluated the effect of i.c.v. injection of cholinergic and noradrenergic agonists, at increasing concentrations, and of muscarinic cholinergic and α1 and α2-adrenoceptor antagonists on blood pressure and urinary sodium handling in SHR, compared with age-matched Wistar Kyoto rats (WR). We confirmed that CCh and NE microinjected into the lateral ventricle (LV) of conscious rats leads to enhanced natriuresis. This response was associated with increased proximal and post-proximal sodium excretion accompanied by an unchanged rate of glomerular filtration. We showed that cholinergic-induced natriuresis in WR and SHR was attenuated by previous i.c.v. administration of atropine and was significantly lower in the hypertensive strain than in WR. In both groups the natriuretic effect of injection of noradrenaline into the LV was abolished by previous local injection of an α1-adrenoceptor antagonist (prazosin). Conversely, LV α2-adrenoceptor antagonist (yohimbine) administration potentiated the action of noradrenaline. The LV yohimbine pretreatment normalized urinary sodium excretion in SHR compared with age-matched WR. In conclusion, these are, as far as we are aware, the first results showing the importance of interaction of central cholinergic and/or noradrenergic receptors in the pathogenesis of spontaneous hypertension. These experiments also provide good evidence of the existence of a central adrenergic mechanism consisting of α1 and α2-adrenoceptors which works antagonistically on regulation of renal sodium excretion.

Classificação de água de coco processada e natural por meio de HCA, PCA e teores de íons metálicos determinados por ICP OES

Inductively Coupled Plasma Optical Emission Spectrometry was used to determine Ca, Mg, Mn, Fe, Zn and Cu in samples of processed and natural coconut water. The sample preparation consisted in a filtration step followed by a dilution. The analysis was made employing optimized instrumental parameters and the results were evaluated using methods of Pattern Recognition. The data showed common concentration values for the analytes present in processed and natural samples. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) indicated that the samples of different kinds were statistically different when the concentrations of all the analytes were considered simultaneously.

Filtros de areia aplicados à irrigação localizada: teoria e prática

The application of sand filters in localized irrigation systems is recommended in the presence of organic and algae contamination. The proper design and maintenance of these equipments are essential to assure an effective water quality control, in order to reduce the emitters clogging, to keep its water application uniformity, and to prevent increasing in the system operation costs. Despite the existence of some references about design, operation and maintenance of these filters, they are dispersed, with not enough details to guarantee the optimization of its hydraulics structure design and the proper selection of porous media to be used. Therefore, the objective of this work was to report a current literature review, relating practical information with scientific knowledge. The content of this review would help to induce and intensify the research on this subject and to contribute so the operational functions for the equipment are reached. It is also expected to assist the improvement of the filtration and flushing processes in the agricultural irrigation and the development of original design procedures and the rational use of these devices.

Rugosidade e pigmentação superficial de materiais ionoméricos

The aim of this study was to compare two methods of surface roughness analysis, perfilometry and spectrophotometry, applied to the surface of ionomeric materials (Chelon Fil, Vitremer and Dyract), submitted to different surface finishing treatments. For the perfilometric analysis, sixty specimens of each material were made and randomly separated into three experimental groups. The average surface roughness (Ra, mm) was measured on each specimen by a surface perfilometer (Mitutoyo Surftest 211). The spectrophotometric analysis consisted in quantifying the dye impregnated in the samples. The dyes used were 0.5% fuchsin and 0.5% erythrosin. Data were submitted to variance analysis (ANOVA) and t-Student test at a 0.05 significance level. There was no linear correlation between average roughness and superficial deposition of dye. Perfilometric analysis revealed that 12- and 30-bladed carbide burs caused the roughest surface of Chelon Fil, followed by Sof-Lex discs and mylar band. There were no significant differences between the specimens submitted to finishing and polishing with Sof-Lex discs and the control group (mylar band) for Vitremer, nevertheless, the highest Ra values were obtained when 12- and 30-bladed burs were used. For Dyract, there was no significant difference between the three treatments. The mean values of superficial deposition of dye for Chelon Fil, Vitremer and Dyract were: 1.7261, 1.4759, 1.3318, respectively. There were no significant differences between the restorative materials when different finishing and polishing systems were used.

CROMATOGRAFIA DE AFINIDADE COM CORANTE RED A versus TROCA IÔNICA-PERMEABILIDADE EM GEL: COMPARAÇÃO DA PRATICIDADE NA PURIFICAÇÃO DE ENTEROTOXINA ESTAFILOCÓCICA A

Culture supernatant of Staphylococcus aureus 722 in 3% triptone plus 1% yeast extract was used for EEA purification, proceeding comparison between dye ligand Red A affinity chromatography and classic chromatography. The capture of SEA with Amberlite CG-50 allowed rapid enterotoxin concentration from the culture supernatant. However, the ratio of 15 mg of the resin to a total of 150 mg of the toxin satured the resin, giving only 10 to 30% of SEA recuperation from the supernatant. The elution of concentrated material throught the Red A column resulted in a recovery of 60,87% of the toxin, and required 76 hours, indicating advantage on classic chromatography. Ion exchange column plus gel filtration recovered only 6,5 % of the SEA, and required 114 hours to conclude the procedure. The eletrophoresis of purified SEA indicated high grade of toxin obtained from Red A column, with 90 % of purity, compared to 60 % of classic column.

Medida da capacidade antioxidante de fluidos biologicos por voltametria de pulso diferencial associada ao uso de surfactante como resposta as adaptações geradas pelo exercicio

Universidade Estadual de Campinas . Faculdade de Educação Física