Analytical derivatizations in environmental analysis.

Analytical derivatization is a technique that alters the structure of an analyte and produces a product more suitable for analysis. While this process can be time-consuming and add reagents to the procedure, it can also facilitate the isolation of the analyte(s), enhance analytes' stability, improve separation and sensitivity, and reduce matrix interferences. Since derivatization is a functional group analysis, it improves selectivity by separating reactive from neutral compounds during sample preparation.

Performance of the microINR Point-of-Care System Used by Self-Testing Patients: A Multicenter Clinical Trial.

 Anticoagulation monitoring is a major practical and clinical challenge. We assessed the performance of the microINR system in patient self-testing (PST).  This study was performed at four US medical centers.

The multiple mini-interview for selecting medical residents: first experience in the Middle East region.

Introduction: Numerous studies have shown that multiple mini-interviews (MMI) provides a standard, fair, and more reliable method for assessing applicants. This article presents the first MMI experience for selection of medical residents in the Middle East culture and an Arab country.

Methods: In 2012, we started using the MMI in interviewing applicants to the residency program of Dubai Health Authority.

Solid phase analytical derivatization as a sample preparation method.

Analytical derivatization (AD) is an important procedure in analysis as it improves the sensitivity, selectivity and chromatographic separation. Solid phase analytical derivatization (SPAD) combines extraction and derivatization into a single step fulfilling many aspects of a good sample preparation technique, which includes low organic solvent consumption, economical, ease of automation with any chromatographic system and applicability in a wide range of complicated matrices. In this review we have focused on wide applications of SPAD when used in combination with different sample preparation methods, such as solid phase extraction, ion exchange resins, solid phase microextraction, in-tube, microfluidic devices, and hollow fiber extraction methods.

Association between a medical school admission process using the multiple mini-interview and national licensing examination scores.

Context: There has been difficulty designing medical school admissions processes that provide valid measurement of candidates' nonacademic qualities.

Objective: To determine whether students deemed acceptable through a revised admissions protocol using a 12-station multiple mini-interview (MMI) outperform others on the 2 parts of the Canadian national licensing examinations (Medical Council of Canada Qualifying Examination [MCCQE]). The MMI process requires candidates to rotate through brief sequential interviews with structured tasks and independent assessment within each interview.

Solid phase analytical derivatization of anthropogenic and natural phenolic estrogen mimics with pentafluoropyridine for gas chromatography-mass spectrometry.

A simple, low cost, fast and sensitive method is reported for the determination of the four endocrine disrupting chemicals (EDCs) 4-tert-butylphenol, 4-tert-octylphenol, bisphenol A and 17β-estradiol using pentafluoropyridine as the derivatizing reagent. These EDCs were determined by simultaneous extraction and derivatization in a solid phase analytical derivatization (SPAD) technique without the aid of any phase transfer catalyst (PTC) or an ion-pair mechanism. Recoveries of analytes as their tetrafluoropyridyl derivatives from water ranged from 71% for 4-tert-butylphenol to 106% for 17β-estradiol; from urine they ranged from 61% for 17β-estradiol to 91% for 4-tert-octylphenol; and from humic acids solution the ranged from 59% for 17β-estradiol to 104% for 4-tert-octylphenol in humic acid solutions.

Predictive validity of the multiple mini-interview for selecting medical trainees.

Introduction: In this paper we report on further tests of the validity of the multiple mini-interview (MMI) selection process, comparing MMI scores with those achieved on a national high-stakes clinical skills examination. We also continue to explore the stability of candidate performance and the extent to which so-called 'cognitive' and 'non-cognitive' qualities should be deemed independent of one another.

Methods: To examine predictive validity, MMI data were matched with licensing examination data for both undergraduate (n = 34) and postgraduate (n = 22) samples of participants.

Determination of malondialdehyde in human plasma by fully automated solid phase analytical derivatization.

Analytical derivatization (AD) increases the sensitivity of analysis by one to three orders of magnitude, stabilizes labile analytes and converts them into readily extractable products. Using a variant of this technique, we applied solid phase analytical derivatization (SPAD) to fully automate extraction, derivatization and liquid chromatography. The resulting device (AutoSPAD) determined malonyldialdehyde (MDA) from biological fluids.

Restoration of vitamin C synthesis in transgenic Gulo-/- mice by helper-dependent adenovirus-based expression of gulonolactone oxidase.

Inability to synthesize vitamin C, because of a deficiency in gulonolactone oxidase (GULO) expression, is a genetic deficiency shared by a small number of animals including humans. Although the most overt symptom of vitamin C deficiency, scurvy, can be readily corrected by modest consumption of vitamin C, there is increasing interest in the effect of high-level administration in treating human disease. Using a previously derived Gulo-expressing vector, which produces murine GULO under the control of the murine cytomegalovirus (mCMV) promoter, we constructed and validated a recombinant helper-dependent adenovirus (HDAd-mCMV-Gulo) that can be used to correct this genetic defect.

Automated derivatization and analysis of malondialdehyde using column switching sample preparation HPLC with fluorescence detection.

Analyte derivatization is advantageous for the analysis of malondialdehyde (MDA) as a biomarker of oxidative stress in biological samples. Conventionally, however, derivatization is time consuming, error-prone and has limited options for automation. We have addressed these challenges for the solid phase analytical derivatization of MDA from small volume tissue homogenate samples.

Multiple mini-interviews predict clerkship and licensing examination performance.

Objective: The Multiple Mini-Interview (MMI) has previously been shown to have a positive correlation with early medical school performance. Data have matured to allow comparison with clerkship evaluations and national licensing examinations.

Methods: Of 117 applicants to the Michael G DeGroote School of Medicine at McMaster University who had scores on the MMI, traditional non-cognitive measures, and undergraduate grade point average (uGPA), 45 were admitted and followed through clerkship evaluations and Part I of the Medical Council of Canada Qualifying Examination (MCCQE).

A cost efficiency comparison between the multiple mini-interview and traditional admissions interviews.

A major expense for most professional training programs, both financially and in terms of human resources, is the interview process used to make admissions decisions. Still, most programs view this as a necessary cost given that the personal interview provides an opportunity to recruit potential candidates, showing them what the program has to offer, and to try and gather more information about the candidates to ensure that those selected live up to the espoused values of the institution. We now have five years worth of experience with a Multiple Mini-Interview (MMI) process that, unlike traditional panel interviews, uses the OSCE model to have candidates interact with a larger number of interviewers.

The effect of defined violations of test security on admissions outcomes using multiple mini-interviews.

Introduction: Heterogeneous results exist regarding the impact of security violations on student performances in objective structured clinical examinations (OSCEs). Three separate studies investigate whether anticipated security violations result in undesirable enhancement of MMI performance ratings.

Methods: Study 1: low-stakes: MMI station stems provided to a random half of 57 medical school applicants 2 weeks in advance of participation in a research study.

Oncogenes and Angiogenesis: down-regulation of thrombospondin-1 in normal fibroblasts exposed to factors from cancer cells harboring mutant ras.

The onset of angiogenesis in cancer often involves down-regulation of endogenous angiogenesis inhibitors, of which thrombospondin-1 (TSP-1) is a paradigm. As this effect is thought to occur under the influence of transforming genetic lesions (e.g.

The ability of the multiple mini-interview to predict preclerkship performance in medical school.

Problem Statement And Background: One of the greatest challenges continuing to face medical educators is the development of an admissions protocol that provides valid information pertaining to the noncognitive qualities candidates possess. An innovative protocol, the Multiple Mini-Interview, has recently been shown to be feasible, acceptable, and reliable. This article presents a first assessment of the technique's validity.

Do clinical clerks provide candidates with adequate formative assessment during Objective Structured Clinical Examinations?

Context: Various research studies have examined the question of whether expert or non-expert raters, faculty or students, evaluators or standardized patients, give more reliable and valid summative assessments of performance on Objective Structured Clinical Examinations (OSCEs). Less studied has been the question of whether or not non-faculty raters can provide formative feedback that allows students to take advantage of the educational opportunity that OSCEs provide. This question is becoming increasingly important, however, as the strain on faculty resources increases.

The relationship between interviewers' characteristics and ratings assigned during a multiple mini-interview.

Purpose: To assess the consistency of ratings assigned by health sciences faculty members relative to community members during an innovative admissions protocol called the Multiple Mini-Interview (MMI).

Method: A nine-station MMI was created and 54 candidates to an undergraduate MD program participated in the exercise in Spring 2003. Three stations were staffed with a pair of faculty members, three with a pair of community members, and three with one member of each group.

An admissions OSCE: the multiple mini-interview.

Context: Although health sciences programmes continue to value non-cognitive variables such as interpersonal skills and professionalism, it is not clear that current admissions tools like the personal interview are capable of assessing ability in these domains. Hypothesising that many of the problems with the personal interview might be explained, at least in part, by it being yet another measurement tool that is plagued by context specificity, we have attempted to develop a multiple sample approach to the personal interview.

Methods: A group of 117 applicants to the undergraduate MD programme at McMaster University participated in a multiple mini-interview (MMI), consisting of 10 short objective structured clinical examination (OSCE)-style stations, in which they were presented with scenarios that required them to discuss a health-related issue (e.