The fragmentation behavior of 18 chlorogenic acids that are not substituted at position 1 has been investigated using LC-MS(4) applied to a methanolic coffee bean extract and commercial cider (hard cider). Using LC-MS(3), it is possible to discriminate between each of the three isomers of p-coumaroylquinic acid, caffeoylquinic acid, feruloylquinic acid, and dicaffeoylquinic acid, and a hierarchical key has been prepared to facilitate this process when standards are not available. MS(4) fragmentations further support these assignments, but were not essential in reaching them. The distinctive behavior of 4-acyl and 3-acyl chlorogenic acids compared with the 5-acyl chlorogenic acids is a key factor permitting these assignments. The fragmentation patterns are dependent upon the particular stereochemical relationships between the individual substituents on the quinic acid moiety. Fragmentation is facilitated by 1,2-acyl participation and proceeds through quinic acid conformers in which the relevant substituents transiently adopt a 1,3-syn-diaxial relationship. Selected ion monitoring at m/z 529 clearly indicated the presence in coffee of six caffeoylferuloylquinic acid isomers, whereas previously only two or three had been demonstrated. The hierarchical key permitted specific structures to be assigned to each of the six isomers. These assignments are internally consistent and consistent with the limited data previously available.
We report on the development of short forms from the Patient-Reported Outcomes Measurement Information System (PROMIS™) Sleep Disturbance (SD) and Sleep-Related Impairment (SRI) item banks. Results from post-hoc computerized adaptive testing (CAT) simulations, item discrimination parameters, item means, and clinical judgment were used to select the best-performing 8 items for SD and SRI. The final 8-item short forms provided less test information than the corresponding full banks, but correlated strongly with the longer forms. The short forms had greater measurement precision than the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS) as indicated by larger test information values across the continuum of severity, despite having fewer total items, a major advantage for both research and clinical settings.
The PROMIS sleep disturbance and SRI item banks have excellent measurement properties and may prove to be useful for assessing general aspects of sleep and SRI with various groups of patients and interventions.
Differences in plasma glucose, insulin, and gastrointestinal hormone profiles further confirm the potent biological action of caffeine and suggest that chlorogenic acid might have an antagonistic effect on glucose transport. Therefore, a novel function of some dietary phenols in humans may be to attenuate intestinal glucose absorption rates and shift the site of glucose absorption to more distal parts of the intestine.
The Patient-Reported Outcomes Measurement Information System (PROMIS®) is an NIH Roadmap initiative devoted to developing better measurement tools for assessing constructs relevant to the clinical investigation and treatment of all diseases—constructs such as pain, fatigue, emotional distress, sleep, physical functioning, and social participation. Following creation of item banks for these constructs, our priority has been to validate them, most often in short-term observational studies. We report here on a three-month prospective observational study with depressed outpatients in the early stages of a new treatment episode (with assessments at intake, one-month follow-up, and three-month follow-up). The protocol was designed to compare the psychometric properties of the PROMIS depression item bank (administered as a computerized adaptive test, CAT) with two legacy self-report instruments: the Center for Epidemiological Studies Depression scale (CESD; Radloff, 1977) and the Patient Health Questionnaire (PHQ-9; Spitzer et al., 1999). PROMIS depression demonstrated strong convergent validity with the CESD and the PHQ-9 (with correlations in a range from .72 to .84 across all time points), as well as responsiveness to change when characterizing symptom severity in a clinical outpatient sample. Identification of patients as “recovered” varied across the measures, with the PHQ-9 being the most conservative. The use of calibrations based on models from item response theory (IRT) provides advantages for PROMIS depression both psychometrically (creating the possibility of adaptive testing, providing a broader effective range of measurement, and generating greater precision) and practically (these psychometric advantages can be achieved with fewer items—a median of 4 items administered by CAT—resulting in less patient burden).
The effect of different classes of dietary polyphenols on intestinal glucose uptake was investigated using polarised Caco-2 intestinal cells. Glucose uptake into cells under sodiumdependent conditions was inhibited by flavonoid glycosides and non-glycosylated polyphenols whereas aglycones and phenolic acids were without effect. Under sodium-free conditions, aglycones and non-glycosylated polyphenols inhibited glucose uptake whereas glycosides and phenolic acids were ineffective. These data suggest that aglycones inhibit facilitated glucose uptake whereas glycosides inhibit the active transport of glucose. The non-glycosylated dietary polyphenols appear to exert their effects via steric hindrance, and (À)-epigallochatechingallate, (À)-epichatechingallate and (À)-epigallochatechin are effective against both transporters.
Objective
To evaluate the responsiveness to change of the PROMIS® negative affect measures (Depression, Anxiety, and Anger) using longitudinal data collected in six chronic health conditions.
Study Design and Setting
Individuals with major depressive disorder (MDD), back pain, chronic obstructive pulmonary disease (COPD), chronic heart failure (CHF), and cancer completed PROMIS negative affect instruments as computerized adaptive test (CAT) or as fixed-length short form (SF) at baseline and a clinically-relevant follow-up interval. Participants also completed global ratings of health. Linear mixed effects models and standardized response means (SRM) were estimated at baseline and follow-up.
Results
903 individuals participated (back pain, n = 218; cancer, n = 304; CHF, n = 60; COPD, n = 125; MDD, n = 196). All three negative affect instruments improved significantly for treatments of depression and pain. Depression improved for CHF patients (anxiety and anger not administered), while anxiety improved significantly in COPD groups (stable and exacerbation). Response to treatment was not assessed in cancer. Subgroups of patients reporting better or worse health showed a corresponding positive or negative average SRM for negative affect across samples.
Conclusion
This study provides evidence that the PROMIS negative affect scores are sensitive to change in intervention studies in which negative affect is expected to change. These results inform the estimation of meaningful change and enable comparative effectiveness research.
The between-laboratory SD of the GI values is approximately 9. Standardized data analysis and low within-subject variation (refCV<30%) are required for accuracy. The results suggest that common misconceptions exist about which factors do and do not need to be controlled to improve precision. Controlled studies and cost-benefit analyses are needed to optimize GI methodology. The trial was registered at clinicaltrials.gov as NCT00260858.
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