Search results for "DETECTION"
showing 10 items of 2543 documents
Micellar Liquid Chromatography: A Worthy Technique for the Determination of β-Antagonists in Urine Samples
1998
Several beta-antagonists (acebutolol, atenolol, celiprolol, labetalol, metoprolol, nadolol, propranolol) were determined in urine samples with fluorometric detection after direct injection, in less than 15 min, with a micellar mobile phase of 0.1 M sodium dodecyl sulfate (SDS), 15% propanol, and 1% triethylamine at pH 3. The limits of detection (38 criterion) were usually between 3 and 30 ng/mL. The addition of propanol and triethylamine and the reduction of the pH of the mobile phase improved the efficiency of the chromatographic peaks that was rather low in pure micellar eluents. The selection of the composition of the mobile phase was easily performed through the use of an interpretive p…
Determination of four parabens and bisphenols A, F and S in human breast milk using QuEChERS and liquid chromatography coupled to mass spectrometry
2018
Abstract For the first time, a multiresidue, sensitive and high throughput method for determination of bisphenol A, F and S and 4 parabens (methyl paraben, ethyl paraben, propyl paraben and butyl paraben) in human breast milk was developed. The proposed method includes an extraction and clean-up procedure based on QuEChERS methodology followed by liquid chromatography coupled to triple quadrupole mass spectrometry determination. Negative atmospheric pressure chemical ionization in the selected reaction monitoring mode was used for mass detection. During the method validation the recoveries varied between 83 and 115% with a precision lower than 20% for all analytes using spiked levels from 0…
Determination of 21 perfluoroalkyl substances and organophosphorus compounds in breast milk by liquid chromatography coupled to orbitrap high-resolut…
2018
Abstract The human exposure to perfluoroalkyl (PFASs) and organophosphorus (OPs) compounds is a cause of concern and its determination in biological matrices, including human milk, is an emergent approach for evaluate their exposure. A comprehensive strategy for the quantitative determination of 21 PFASs and OPs compounds in breast milk was developed. The proposed method includes an extraction and clean-up procedure based on the QuEChERs methodology followed by an ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS) determination. The full-scan mass data were acquired with a resolution of 50000 FWHM and a mass accuracy better than 5 ppm. Met…
On-Capillary Surface-Enhanced Raman Spectroscopy: Determination of Glutathione in Whole Blood Microsamples.
2018
Oxidative stress monitoring in the neonatal period supports early outcome prediction and treatment. Glutathione (GSH) is the most abundant antioxidant in most cells and tissues, including whole blood, and its usefulness as a biomarker has been known for decades. To date, the available methods for GSH determination require laborious sample processing and the use of sophisticated laboratory equipment. To the best of our knowledge, no tools suitable for point-of-care (POC) sensing have been reported. Surface-enhanced Raman spectroscopy (SERS), performed in a microvolume capillary measurement cell, is proposed in this study as a robust approach for the quantification of GSH in human whole blood…
A randomized trial comparing conventional cytology to liquid-based cytology and computer assistance.
2012
Liquid-based cytology (LBC) has replaced conventional cytology (CC) for cervical cancer screening in some countries. However, it remains unclear whether LBC is superior to CC. A randomized controlled trial was conducted between August 2007 and March 2009 in Germany to compare LBC, alone and in combination with computer-assisted imaging technology (CAS), to CC in the detection of histologically confirmed cervical intraepithelial neoplasia (CIN). The main outcome measures were detection rates, relative sensitivities, positive predictive values (PPVs) and relative PPVs comparing LBC without and with CAS to CC. Primary histological outcome was CIN2 or higher. Included were 20,627 women particip…
Oral human papillomavirus infection in women with cervical HPV infection: new data from an Italian cohort and a metanalysis of the literature.
2011
Summary A key issue in oral HPV infection is whether it can be associated with a genital HPV infection, or whether it can be considered as an independent event. This analysis evaluated the frequency and type-concordance of oral HPV infection in women with cervical HPV infection by means of: (i) a cross-sectional study on a sample (n = 98) of Italian women; and (ii) a literature-based metanalysis, including the experimental study the subject of this Paper and nine other published studies (n = 1017), which also examined the influence of oral sampling procedure (oral brushing vs oral rinse) and HIV status on oral HPV detection. The prevalence of oral HPV infection in the Italian study was 14.3…
The attentional blink demonstrates automatic deviance processing in vision.
2011
Rare deviations in serial visual stimulation are accompanied by an occipital N2 in the event-related potential [the visual mismatch negativity (vMMN)]. Recent research suggests that the vMMN reflects automatic processing of information on the sensory level as a basis for change detection. To directly test the hypothesis that the vMMN is independent from attention, a rapid-serial-visual-presentation paradigm was applied: Either 300 ms or 700 ms after the presentation of a target (T1) a rare position change was embedded in the stimulation which elicited a vMMN. In another condition participants had to detect a second target (T2) after T1: Importantly, within 300 ms after T1, T2 detection was …
Development of a novel methodology for determination of dialkyl phosphates in human urine using liquid chromatography-tandem mass spectrometry
2019
Abstract In this study a fast and sensitive method was developed for the quantitative determination of six dialkyl phosphates (DAPs) in human urine using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The proposed methodology was based on liquid-liquid extraction (LLE) with diethyl ether and ethyl acetate using MgSO4 and NaCl, followed by liquid chromatography and mass spectrometry detection in the selected reaction mode (SRM) with negative electrospray ionization (ESI-). Detection settings were optimized by design of experiments (DoE). Dibutyl phosphate (DBP) was used as internal standard. Several criteria established in the SANTE/11813/2017 guidance document for pesticide resi…
MAGIC-5: an Italian mammographic database of digitised images for research
2008
The implementation of a database of digitised mammograms is discussed. The digitised images were collected beginning in 1999 by a community of physicists in collaboration with radiologists in several Italian hospitals as a first step in developing and implementing a computer-aided detection (CAD) system. All 3,369 mammograms were collected from 967 patients and classified according to lesion type and morphology, breast tissue and pathology type. A dedicated graphical user interface was developed to visualise and process mammograms to support the medical diagnosis directly on a high-resolution screen. The database has been the starting point for developing other medical imaging applications,…
Global, regional, and national burden of colorectal cancer and its risk factors, 1990–2019: a systematic analysis for the Global Burden of Disease St…
2022
Correction to Lancet Gastroenterol Hepatol 2022; 7: 627-47. Lancet Gastroenterol Hepatol. 2022 Aug;7(8):704. doi: 10.1016/S2468-1253(22)00210-2. PMID: 35809605. Background: Colorectal cancer is the third leading cause of cancer deaths worldwide. Given the recent increasing trends in colorectal cancer incidence globally, up-to-date information on the colorectal cancer burden could guide screening, early detection, and treatment strategies, and help effectively allocate resources. We examined the temporal patterns of the global, regional, and national burden of colorectal cancer and its risk factors in 204 countries and territories across the past three decades. Methods: Estimates of incidenc…