DETERMINATION OF TRAZODONE IN HUMAN PLASMA BY REVERSED-PHASE LIQUID CHROMATOGRAPHY-MASS SPECTROMETRY WITH ELECTROSPRAY IONISATION

Objective: The development and validation of LC-MS/MS method for quantification of Trazodone (a serotonin antagonist and reuptake inhibitor (SARI), which is a second generation antidepressant compound belonging to the class of phenyl piperazine) in human plasma is described. Methods: The method involves protein precipitation (extraction) using Trazodone d6 as an internal standard (IS). Chromatographic separation is achieved on Zorbax eclipse XDB C8 150×4.6 mm, 5 μm column with a mobile phase consisting of 2 mM ammonium formate (pH 3.0) and methanol (30:70 v/v) at a flow rate of 1.0 mL / min and the total run time was 2.5 minute. Detection was carried out by AB Sciex API 3200 tandem mass spectrometer using positive electro-spray ionization mode by multiple reactions monitoring method at m/z 372.00→176.10 and 378.20→182.10 for Trazodone and Trazodone d6 (ISTD) respectively with dwell times of 300 msecs for each of the transitions. Results: The standard curve was linear from 5.203 ng / mL to 3025.166 ng / mL with goodness of fit (r2) greater than 0.990 observed during the method validation batches. This assay allows quantification of Trazodone at a concentration as low as 5 ng / mL in human plasma. The observed mean recovery was 88% for the drug. Conclusions: The method described here is found to be simple, cost effective and suitable for the use in bioequivalence and bioavailability studies

Gender differences in presbyopia

Presbyopia is the loss of lens accommodation with age that results in an inability to focus at near distances. It is receiving growing attention because of the recognition that good near vision is needed to accomplish a broad range of tasks, not only reading and writing

Presbyopia: prevalence, impact, and interventions

Presbyopia is an age-related loss of lens accommodation that results in an inability to focus at near distances. It is the most common physiological change occurring in the adult eye and is thought to cause universal near vision impairment with advancing age

Measures of Visual Function and Percentage of Preferred Walking Speed in Older Adults: The Salisbury Eye Evaluation Project

PURPOSE. The purpose of this study was to determine the association of static (visual acuity, visual fields, and contrast sensitivity) and dynamic (dynamic visual acuity and motion threshold) measures of vision with mobility performance on a mobility course with obstacles. METHODS. A cross-sectional population-based study of 1504 persons aged 72 to 92 years enrolled in the third round of the Salisbury Eye Evaluation Project. Standardized examinations were used to test binocular visual acuity, better eye-contrast sensitivity, visual fields, dynamic visual acuity, and motion threshold. Cognitive status was assessed by using the standardized Mini-Mental State Examination. Participants were timed when walking a straight 4-m distance and when walking through a mobility course seeded with obstacles. The percentage of preferred walking speed (PPWS) for each subject was calculated as the ratio of mobility course speed to a 4-m walking speed expressed as a percentage. RESULTS. The mean age of the participants was 78.2 years. The mean 4-m walking speed was 0.82 m/s, whereas the mean mobility course speed was 0.47 m/s. The mean PPWS was 57.1%. All vision variables except visual acuity were associated with PPWS in univariate analyses. Multivariate models found visual fields and the cognitive state to be associated with PPWS. There was no association with dynamic measures of vision. CONCLUSIONS. The mobility performance, as measured by PPWS, was associated with visual fields but not with visual acuity, contrast sensitivity, or dynamic vision measures. Deficits in cognition also play an important role in predicting mobility performance. (Invest Ophthalmol Vis Sci. 2006;47:65- 2 Aging brings with it the prospect of losing independence, and vast efforts are currently being made to study the factors leading to reduced quality of life in a bid to give the growing elderly population more active years. One such factor is the mobility of individuals. A basic level of physical mobility is required to manage many of the activities of daily living satisfactorily. 3 Reduced mobility performance has been shown to be associated with functional dependence, 4,5 falls in the elderly, 6,7 and nursing home placement, 8 -12 and it also has been found to predict depression. 13 Many studies have looked at the link between mobility and mortality, and have shown an association. 3,8,14 -16 Apart from the personal costs, the adverse sequelae of mobility impairment carry huge costs to society as well. 20,21 Small-scale convenience samples of visually impaired and/or older adults have shown that decrements in vision adversely affect mobility performance. Mobility performance can be measured by using several metrics. Some studies have used the number of errors or bumps 24 -26,30 PPWS was put forward by Clark-Carter et al. METHODS Subjects The Salisbury Eye Evaluation Project is a longitudinal, population-based study of community-dwelling seniors residing in Wicomico County, MD. The original sample was collected in 1993 and comprised 2520 persons aged 65 to 84 years. A description of the original cohort can be found elsewhere. 34 Data for this study were collected in round three of the study, which was conducted between 1999 and 2000. Follow-up rates were 95% and 86% of those still alive for the second and third rounds, respectively. The participants (n ϭ 1504) were aged between 72 and 92 years. Basic demographic data were obtained from a structured questionnaire. Cognitive status was assessed by using the standardized Mini-Mental State Examination (MMSE)

Visual Functioning and Health-related Quality-of-Life are Compromised in Patients with Uveitis

<p><i>Purpose</i>: To assess the vision-related (VR) and health-related (HR) quality-of-life (QoL) of patients with uveitis.</p> <p><i>Methods</i>: In total, 60 patients with uveitis, 81 patients with diabetic retinopathy (DR), and 70 healthy subjects completed the National Eye Institute Visual Functioning Questionnaire and the Medical Outcome Study 36-Item Short Form.</p> <p><i>Results</i>: Patients with uveitis reported lower HR- and VR-QoL than healthy subjects (<i>p<</i>0.05) and lower VR-QoL (<i>p<</i>0.001) than patients with DR. For patients with uveitis, multiple linear regression analyses indicated that lower HR-QoL scores were predicted by younger age (<i>p<</i>0.01), while lower VR-QoL scores were predicted by poorer visual acuity (<i>p</i><0.001), ocular comorbidities (<i>p</i><0.05), and female sex (<i>p</i><0.05).</p> <p><i>Conclusions</i>: Patients with uveitis have significantly poorer VR- and HR-QoL than healthy control subjects. Uveitis has a more debilitating impact on VR-QoL than DR.</p