On line extraction and separation of bendiocarb, methomyl, methylparathion, and pentachlorophenol pesticides from raw milk

A high performance liquid chromatography (HPLC) method for extraction and determination of pesticides from raw milk was developed. The method involves direct injection of raw milk samples on a bovine serum albumin-dimethyl-octyl-silica gel (BSA-Si-Cs) column. The mobile phase 0.05 mol.L-1 phosphate buffer pH6.0 in acetonitrile (70:30 v/v) was employed for extraction and separation of bendiocarb, methylparathion, pentachlorophenol, and methomyl pesticides. The method shows good results of recovery in the pesticides studied, higher than 99.6%.

Off line extraction of phenol from human urine sample with isoamyl alcohol and determination by HPLC

This method has been developed for extraction and determination of phenol in a urine sample by high performance liquid chromatography.After acid hydrolysis, the free phenol was extracted with isoamyl alcohol solvent, followed by back extraction with 0.5 mol.L-1 sodium hydroxide solution and analyzed by an isocratic HPLC Varian System, equipped with reverse-phase column (MicroPak-C-18). The mobile phase was acetonitrile in 0.01 mol.L-1 hydrochloric acid solution, (20:80 v/v), and at a now-rate of 1.0 mL.min-1. The chromatogram was monitored at 220 nm in room temperature. The identification was based on retention time and the quantification was performed by automatic peak-area determination, corrected for the external standards method.The recovery was higher than 99.5 % for phenol and reproducibility of method was shown to be 2.3% standard deviation and 5.6% coefficient of variance (n=20). The limit detection was 0.05 mgL(-1) and a range of 0.05 to 20.0 mgL(-1) of phenol for linearity.

Analysis of the performance of an extraction-condensation steam turbine on a cogeneration system of a Brazilian sugar-alcohol factory

In this work a detailed thermodynamic analysis for an extraction-condensation steam turbine capable to drive a 40 MVA electricity generator in a sugar-alcohol factory was carried out. The use of this turbine in the cogeneration system showed that its efficiency contributed to increase the power generation, although the condensation reduces the overall efficiency of the plant. Sensibility analyses were performed to evaluate the behavior of the overall energy efficiency of a plant with the extraction-condensation turbine in function of the boiler efficiency, the specific consumption of steam in the processes and the condensation rate in the turbine. It was observed that the plant efficiency is very sensible to the condensation rate variation and it increases when there is an increase in the demand of steam for processes.

Influence of alkaline extraction on the characteristics of humic substances in Brazilian soils

An investigation was made of the influence of alkaline extraction on the characteristics of humic substances extracted from Brazilian soil samples. Humic substances (HS) from seven different soils samples collected in Brazil were extracted using the procedure recommended by the International Humic Substances Society (IHSS). Soils, HS and humins were characterized by thermogravimetry and differential thermal analysis. About 8 mg of each material (soil, HS and humin) were placed in a platinum crucible and heated continuously from 20 to 750 degrees C at a heating rate of 10 degrees C min(-1) in an atmosphere of synthetic air (100 ml min(-1)). A thermal analysis revealed a difference between the content and structural characteristics of organic matter present in HS and humin fractions in relation to their soils. The results indicated that alkaline extraction alters the characteristics of humic substances during the extraction process, underlining the importance of developing methodologies and analytical procedures that allow organic matter in soils to be studied without extracting it. (c) 2005 Elsevier B.V. All rights reserved.

Banana Peel Applied to the Solid Phase Extraction of Copper and Lead from River Water: Preconcentration of Metal Ions with a Fruit Waste

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Selenium determination in tissue samples of Nile tilapia using ultrasound-assisted extraction

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

4-amine-2-mercaptopyrimidine modified silica gel applied in Cd(II) and Pb(II) extraction from an aqueous medium

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Preconcentration and determination of Cu(II) in a fresh water sample using modified silica gel as a solid-phase extraction adsorbent

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Insulin secretion, insulin sensitivity, and hepatic insulin extraction in first-degree relatives of type 2 diabetic patients

To identify early metabolic abnormalities in type 2 diabetes mellitus, we measured insulin secretion, sensitivity to insulin, and hepatic insulin extraction in 48 healthy normal glucose-tolerant Brazilians, first-degree relatives of type 2 diabetic patients (FH+). Each individual was matched for sex, age, weight, and body fat distribution with a person without history of type 2 diabetes (FH-). Both groups were submitted to a hyperglycemic clamp procedure (180 mg/dl). Insulin release was evaluated in its two phases. The first was calculated as the sum of plasma insulin at 2.5, 5.0, 7.5, and 10.0 min after the beginning of glucose infusion, and the second as the mean plasma insulin level in the third hour of the clamp procedure. Insulin sensitivity index (ISI) was the mean glucose infusion rate in the third hour of the clamp experiment divided by the mean plasma insulin concentration during the same period of time. Hepatic insulin extraction was determined under fasting conditions and in the third hour of the clamp procedure as the ratio between C-peptide and plasma insulin levels. FH+ individuals did not differ from FH- individuals in terms of the following parameters [median (range)]: a) first-phase insulin secretion, 174 (116-221) vs 207 (108-277) µU/ml, b) second-phase insulin secretion, 64 (41-86) vs 53 (37-83) µU/ml, and c) ISI, 14.8 (9.0-20.8) vs 16.8 (9.0-27.0) mg kg-1 min-1/µU ml-1. Hepatic insulin extraction in FH+ subjects was similar to that of FH- ones at basal conditions (median, 0.27 vs 0.27 ng/µU) and during glucose infusion (0.15 vs 0.15 ng/µU). Normal glucose-tolerant Brazilian FH+ individuals well-matched with FH- ones did not show defects of insulin secretion, insulin sensitivity, or hepatic insulin extraction as tested by hyperglycemic clamp procedures.

Cataract prevalence in Central-West region of São Paulo State, Brazil

OBJETIVO: A catarata é a principal causa tratável de cegueira e deficiência visual em países subdesenvolvidos. Este estudo foi realizado para avaliar se a catarata continua sendo uma importante causa de cegueira no centro-oeste do Estado de São Paulo. MÉTODOS: Um estudo transversal, de caráter observacional, realizado em cinco cidades da região centro-oeste do Estado de São Paulo, para as quais o centro de referência é a cidade de Botucatu. A amostra estabelecida para este estudo, de forma aleatória, seria composta por 5.555 indivíduos, sendo que foram examinados 4.229 indivíduos (8.458 olhos), ou seja, 78% da amostra pretendida. Os indivíduos foram submetidos a um exame oftalmológico completo que consistia em avaliação da acuidade visual (com e sem correção), tonometria, biomicroscopia, fundoscopia e exame refracional. O diagnóstico de catarata foi dado aos indivíduos que apresentassem opacidade de cristalino na biomicroscopia, de acordo com o Sistema de Classificação de Opacidade do Cristalino II (LOCS II). Olhos apresentando deficiência visual ou cegueira, com a melhor correção e causados por catarata, foram considerados após excluir outras patologias que pudessem causar baixa da acuidade visual (AV). Olhos com deficiência visual foram considerados quando 0,05 < AV < 0,3 e olhos cegos quando AV < 0,05. Indivíduos com deficiência visual foram considerados quando 0,05 < AV < 0,3 e indivíduos cegos quando AV < 0,3, no melhor olho com a melhor correção. Foi considerado o número de olhos com catarata, o número de olhos com deficiência visual e cegueira e o número de indivíduos com deficiência visual e cegueira. RESULTADOS: A prevalência de catarata na população estudada foi de 4,94% (209 indivíduos), afetando principalmente indivíduos com mais de 50 anos (92,34%) e do sexo feminino (61,11%). A catarata foi a causa de deficiência visual para 0,96% e a causa de cegueira para 0,52% de toda a população estudada. CONCLUSÃO: Nossos resultados mostraram que a prevalência de catarata na população estudada é semelhante aos índices de países desenvolvidos.

FAAS determination of metal nutrients in fish feed after ultrasound extraction

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Action of nicotine and ovariectomy on bone regeneration after tooth extraction in rats

Purpose: The purpose of this study was to evaluate the effects of nicotine and ovariectomy on alveolar bone regeneration after exodontias in rats.Materials and Methods: For 30 days, sham ovariectomized (OVX)/NaCl, sham OVX/nicotine, OVX/NaCl, and OVX/nicotine animals were given 2 daily injections of saline or hemisulfate of nicotine. After this period, exodontic procedures were carried out and treatment continued up to the time of euthanasia on clays 7 and 14 when the alveoli were removed for further analyses.Results: The data confirmed that nicotine significantly delays the alveolar regeneration process after dental extraction in rats and showed that the association of nicotine with ovariectomy exacerbates these results.Conclusion: These results indicate that nicotine potentiated the effect of estrogen deficiency on bone regeneration induced by ovariectomy. (c) 2010 American Association of Oral and Maxillofacial Surgeons Oral Maxillofac Surg 68:2675-2681, 2010

Comparative Analysis of 2-Flap Designs for Extraction of Mandibular Third Molar

Objective: The objective of the study was to analyze 2-flap designs for surgical extraction of third molar, evaluating the periodontal status of the second lower molar.Study Design: Forty-five lower third molars were extracted from 24 patients. In 23 teeth, a vertical incision to the mandibular ramus was used (technique A), whereas 22 teeth were submitted to classic L-shaped flap (technique B) with controls at 60 and 90 days postoperatively.Results: Pearson correlation coefficient analysis showed a significant correlation only between immediate preoperative probing depth variables from techniques A and B in the studied surfaces. Statistical significances in the preoperative (vestibular) and postoperative day 60 (distovestibular and vestibular) were noted. In contrast, Student t-test showed no statistical difference in probing depths between preoperative and postoperative values, as well as no statistically significant difference regarding the type of incision alone.Conclusions: Technique A allowed a less traumatic surgery, guaranteeing a more comfortable postoperative period.

Therapeutic Effects of Low-Level Laser Therapy After Premolar Extraction in Adolescents: A Randomized Double-Blind Clinical Trial

Objective: The purpose of this study was to evaluate the effect of low-level laser therapy (LLLT) on wound healing process and pain levels after premolar extraction in adolescents. Background data: The advantage of using LLLT in oral surgeries is the reduction of inflammation and postoperative discomfort; however, the optimal dosing parameters and treatment effects in surgical procedures are inconclusive. Methods: A double-blind, randomized, controlled clinical trial was conducted with 14 patients who were to undergo surgical removal of premolars. Patients were randomly allocated to the LLLT (test) group and placebo (control) group. Patients in the test group received 5.1 J (60 J/cm(2)) of energy density of a gallium-aluminum-arsenide (GaAlAs) diode laser (wavelength, 830 nm; output power, 0.1 W) at three different points intraorally, 1 cm from the target tissue immediately and at 48 and 72 h after the surgical procedure. For patients in the placebo group, the laser device was applied to the same points without activating the hand piece. The wound healing process was evaluated by an independent examiner by visual inspection with the support of digital photographs at baseline and 2, 7, and 15 days postoperatively. Patients recorded the degree of pain using the visual analogue scale (VAS). Results: Compared with the placebo group, the test group showed a lower intensity of pain, but this difference was not statistically significant at any time point. The wound healing process was similar in both groups. Conclusions: Within the limitations of this study, the LLLT parameters used neither increased the wound healing process nor significantly decreased pain intensity after premolar extraction in adolescents.

Evaluation of Cu, Mn, and Se in Vegetables Using Ultrasonic Extraction and GFAAS Quantification

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)