493 research outputs found

    Evaluation of Acetylcholinesterase Biosensor Based on Carbon Nanotube Paste in the Determination of Chlorphenvinphos

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    An amperometric biosensor for chlorphenvinphos (organophosphorus pesticide) based on carbon nanotube paste and acetylcholinesterase enzyme (CNTs-AChE biosensor) is described herein. This CNTs-AChE biosensor was characterized by scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The SEM result shows the presence of CNTs and small lumps, due to the enzyme AChE, which has a type of cauliflower formation. From EIS analysis is possible to observe increased Rtc for CNTs-AChE biosensor when compared to the carbon nanotube paste electrode for the reaction [Fe(CN)6]4−/3−. Using a chronoamperometric procedure, a linear analytical curve was observed in the 4.90 × 10−7–7.46 × 10−6 M range with limit of detection of 1.15 × 10−7 M. The determination of chlorphenvinphos in the insecticide sample proved to be in agreement with the standard spectrophotometric method, with a 95% confidence level and with a relative error lower than 3%. In this way, the CNTs-AChE biosensor presented easy preparation, fast response, sensitivity, durability, good repeatability, and reproducibility

    “Influence of the Therapy with Dorzolamide on the Corneal Structures: Analysis by Confocal Microscopy (CS3)”

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    Purpose: To value, in vivo, with the confocal microscopy(CS3) the corneal microscopic changes in a group of patients in therapy with Dorzolamide 2% eyedrops. Methods:Thirty patients (sixty eyes) with monocular hypertension (IOP21 mmHg) and no previous ipotonic therapy were recruited. The hypertensive eye (HE)was treated with Dorzolamine 2% eyedrops three times daily, the normal tension eye (NE) was used as the control eye. At the time of recruitment, one and three months after the beginning of treatment were performed: applanation tonometry, ultrasound pachimetry (USP), and a CS examination. Results: Mean age was 41,13±10,515 year, at the recruitment time: mean IOP was 16,50±2.34 mmHg in the NE and 22,06±0.68 mmHg in the HE, USP was 542,50±31,18 µ in the NE and 536,63±38,08 in the HE, endothelial cell density was (cell/mm2) 2473,37±339,58 in the NE and 2386,94±284,16 in the HE, stromal reflectivity was 0.36±0.06 in the NE and 0.36±0.05 in the HE. At each control time the IOP was statistically reduced in the treated eyes of a mean of 7,25 mmHg (p<0.01), all the corneal data didn’t show a statistically significant change during the follow–up period, only the stromal reflectivity seemed to be increased in the last control of 0,1 (p<0.005). Conclusions: The CS3 examination allowed us to value the microscopic corneal structure and to show that no clinically significant changes were produced by dorzolamide local therapy

    Thrips (Thysanoptera: Thripidae, Phlaeothripidae) damaging peach in Paranapanema, São Paulo State, Brazil.

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    Objetivando identificar as espécies de tripes associadas ao pessegueiro e as injúrias causadas, pomares das cultivares Aurora e Tropic Beauty foram monitorados semanalmente, de maio a agosto de 2005, no Distrito de Holambra II, em Paranapanema, SP. Flores e frutos de cada seis plantas por hectare foram amostrados pela técnica da batida. Foram identificadas Frankliniella occidentalis (Pergande), F. schultzei (Trybom), F. gardenia (Moulton), F. condei John, F. insularis (Franklin) e Thrips tabaci Lindeman em Thripidae, e, Haplothrips gowdeyi (Franklin) em Phlaeothripidae. F. occidentalis foi dominante compondo 55,7% do total de espécimes amostrado. Injúrias leves e severas foram registradas nos frutos. Seeking to identify thrips species associated to peach and the injuries they cause, plants of Aurora and Tropic Beauty cultivars were weekly monitored, from May to August of 2005, in Holambra II district, in Paranapanema, SP. Flowers and fruits from six plants per hectare were sampled by the hitting technique. Frankliniella occidentalis (Pergande), F. schultzei (Trybom), F. gardenia (Moulton), F. condei John, F. insularis (Franklin) and Thrips tabaci Lindeman, in Thripidae,and Haplothrips gowdeyi (Franklin), in Phlaeothripidae were identifi ed. F. occidentalis was dominant, comprising 55.7% of the total specimens sampled. Slight and severe injuries were registered in fruits.KEY WORDS: Rosaceae, thysanopteran, pest species, habitDisponível também no formato online

    Fenestrated-branched endovascular repair for distal thoracoabdominal aortic pathology after total aortic arch replacement with frozen elephant trunk

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    Objective: To report the outcomes of fenestrated-branched endovascular repair (FBEVAR) for thoracoabdominal aortic pathology after total aortic arch replacement with frozen elephant trunk (TAR+FET). Methods: Interrogation of prospectively maintained databases from four high-volume aortic centers identified consecutive patients treated with distal FBEVAR after prior TAR+FET between August 2013 and September 2020. The primary end point was 30-day/in-hospital mortality. Secondary end points were technical success, early clinical success, midterm survival, and freedom from reintervention. Data are presented as median (interquartile range). Results: A total of 39 patients (21 men; median age, 73 years [67-75 years]) with degenerative (n = 22) and postdissection thoracoabdominal aortic aneurysms (n = 17) (median diameter, 71 mm [61-78 mm]) were identified. Distal FBEVAR was intended in 27 patients (median interval, 9.8 months [6.2-16.6 months]), anticipated in 7, and unexpected in 5. A total of 31 patients had a two- (n = 24) or three-stage (n = 7) distal FBEVAR. Renovisceral target vessel preservation was 99.3% (145 of 146). Early primary and secondary technical success was 92% and 97%, respectively. Thirty-day mortality was 2.6% (n = 1; respiratory failure and spinal cord ischemia [SCI]). Six survivors also developed SCI, which was associated with complete (n = 4) or partial recovery (n = 2) at hospital discharge. No patients required renal replacement therapy or suffered a stroke. Early clinical success was 95%. Median follow-up was 30.5 months (23.7-49.7 months). Eleven patients required 16 late reinterventions. Estimated 3-year survival and freedom from reintervention were 84% ± 6% and 63% ± 10%, respectively. Conclusions: Distal FBEVAR after prior TAR+FET is associated with high technical success and low early mortality. The risk of SCI is significant although the majority of patients demonstrate full or partial recovery before hospital discharge. Midterm patient survival is favorable, but there remains a high requirement for late reintervention. FBEVAR represents an acceptable alternative to distal open thoracoabdominal aortic aneurysm repair

    Genetic study of atypical femoral fractures using exome sequencing in three affected sisters and three unrelated patients

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    Objectives: Atypical femoral fractures (AFF) are rare, often related to long-term bisphosphonate (BPs) tre- atment. Their pathogenic mechanisms are not precisely known and there is no evidence to identify patients with a high risk of AFF. The aim of this work is to study the genetic bases of AFFs. Material and methods: Whole-exome sequencing was carried out on 3 sisters and 3 unrelated additional patients, all treated with BPs for more than 5 years. Low frequency, potentially pathogenic variants sha- red by the 3 sisters, were selected, were selected and a network of gene and protein interactions was constructed with the data found. Results: We identified 37 rare variants (in 34 genes) shared by the 3 sisters, some not previously descri- bed. The most striking variant was the p.Asp188Tyr mutation in the enzyme geranylgeranyl pyrophos- phate synthase (encoded by the GGPS1 gene), from the mevalonate pathway and essential for osteoclast function. Another noteworthy finding was two mutations (one in the 3 sisters and one in an unrelated patient) in the CYP1A1 gene, involved in the metabolism of steroids. We identified other variants that could also be involved in the susceptibility to AFFs or in the underlying osteoporotic phenotype, such as those present in the SYDE2, NGEF, COG4 and FN1 genes. Conclusions: Our data are compatible with a model where the accumulation of susceptibility variants could participate in the genetic basis of AFFs
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