Characterisation of gas reference materials for underpinning atmospheric measurements of stable isotopes of nitrous oxide

The precise measurement of the amount fraction of atmospheric nitrous oxide (N2O) is required to understand global emission trends. Analysis of the site-specific stable isotopic composition of N2O provides a means to differentiate emission sources. The availability of accurate reference materials of known N2O amount fractions and isotopic composition is critical for achieving these goals. We present the development of nitrous oxide gas reference materials for underpinning measurements of atmospheric composition and isotope ratio. Uncertainties target the World Metrological Organisation Global Atmosphere Watch (WMO-GAW) compatibility goal of 0.1 nmol mol−1 and extended compatibility goal of 0.3 nmol mol−1, for atmospheric N2O measurements in an amount fraction range of 325–335 nmol mol−1. We also demonstrate the stability of amount fraction and isotope ratio of these reference materials and present a characterisation study of the cavity ring-down spectrometer used for analysis of the reference materials.</p

BEfree: A new psychological program for binge eating that integrates psychoeducation, mindfulness, and compassion

Background Binge eating disorder (BED) is associated with several psychological and medical problems, such as obesity. Approximately 30% of individuals seeking weight loss treatments present binge eating symptomatology. Moreover, current treatments for BED lack efficacy at follow‐up assessments. Developing mindfulness and self‐compassion seem to be beneficial in treating BED, although there is still room for improvement, which may include integrating these different but complimentary approaches. BEfree is the first program integrating psychoeducation‐, mindfulness‐, and compassion‐based components for treating women with binge eating and obesity. Objective To test the acceptability and efficacy up to 6‐month postintervention of a psychological program based on psychoeducation, mindfulness, and self‐compassion for obese or overweight women with BED. Design A controlled longitudinal design was followed in order to compare results between BEfree (n = 19) and waiting list group (WL; n = 17) from preintervention to postintervention. Results from BEfree were compared from preintervention to 3‐ and 6‐month follow‐up. Results BEfree was effective in eliminating BED; in diminishing eating psychopathology, depression, shame and self‐criticism, body‐image psychological inflexibility, and body‐image cognitive fusion; and in improving obesity‐related quality of life and self‐compassion when compared to a WL control group. Results were maintained at 3‐ and 6‐month follow‐up. Finally, participants rated BEfree helpful for dealing with impulses and negative internal experiences. Conclusions These results seem to suggest the efficacy of BEfree and the benefit of integrating different components such as psychoeducation, mindfulness, and self‐compassion when treating BED in obese or overweight women. Key Practitioner Message The current study provides evidence of the acceptability of a psychoeducation, mindfulness, and compassion program for binge eating in obesity (BEfree); Developing mindfulness and self‐compassionate skills is an effective way of diminishing binge eating, eating psychopathology and depression, and increasing quality of life in women with obesity; Integrating psychoeducation, mindfulness, and compassion seem to be effective in diminishing binge eating, with results maintained up to 6‐month postintervention

Ancient encaustic: An experimental exploration of technology, ageing behaviour and approaches to analytical investigation

The composition of the ancient wax-based painting technique known as encaustic has long been the subject of debate. Ancient sources provide few details of the technology, and modern understanding of the medium is restricted to theoretical interpretation and experimental observation. In this multi-analytical collaborative study, a number of analytical approaches were used to investigate the physical and molecular properties of a range of experimentally prepared encaustic paints before and after ageing. Analysis using gas chromatography mass spectrometry, Fourier transform infrared spectroscopy (invasive and non-invasive), X-ray diffraction and thermogravimetric analysis demonstrated how differences in the technology of production alter the properties and composition of the medium and showed how these are modified by the addition of pigment and the effects of ageing. Comparison of results from the different analytical techniques highlights the benefit of an integrated analytical approach to the analysis of ancient encaustic paints and the fundamental importance of insights from invasive study to evaluating the results of non-invasive analysis

Mortality and Cardiovascular Disease among Older Live Kidney Donors

Over the past two decades, live kidney donation by older individuals (≥55 years) has become more common. Given the strong associations of older age with cardiovascular disease (CVD), nephrectomy could make older donors vulnerable to death and cardiovascular events. We performed a cohort study among older live kidney donors who were matched to healthy older individuals in the Health and Retirement Study. The primary outcome was mortality ascertained through national death registries. Secondary outcomes ascertained among pairs with Medicare coverage included death or CVD ascertained through Medicare claims data. During the period from 1996 to 2006, there were 5717 older donors in the United States. We matched 3368 donors 1:1 to older healthy nondonors. Among donors and matched pairs, the mean age was 59 years; 41% were male and 7% were black race. In median follow-up of 7.8 years, mortality was not different between donors and matched pairs (p = 0.21). Among donors with Medicare, the combined outcome of death/CVD (p = 0.70) was also not different between donors and nondonors. In summary, carefully selected older kidney donors do not face a higher risk of death or CVD. These findings should be provided to older individuals considering live kidney donation

Relationships Between Daily Acute Glucose Fluctuations and Cognitive Performance Among Aged Type 2 Diabetic Patients

The mean amplitude of glycemic excursions (MAGE) is a significant deter-minant of overall metabolic control as well as increased risk for diabetes complications. Older individuals with type 2 diabetes are more likely to have moderate cognitive deficits and structural changes in brain tissue. Considering that poor metabolic control is considered a deranging factor for cognitive performance in diabetic patients, we evaluated whether the contributions of MAGE to cognitive status in older patients with type 2 diabetes were independent from the main markers of glycemic control, such as sustained chronic hyperglycemia (A1C), postprandial glycemia (PPG), and fasting plasma glucose (FPG)RESEARCH DESIGN AND METHODS — In 121 older patients with type 2 diabetes, 48-h continuous subcutaneous glucose monitoring (CSGM) were assessed. MAGE and PPG were evaluated during CSGM. The relationship of MAGE to performance on cognitive tests was assessed, with adjustment for age, glycemic control markers, and other determinants of cognitive status. The cognitive tests were a composite score of executive and attention functioning and the Mini Mental Status Examination (MMSE). RESULTS — MAGE was significantly correlated with MMSE (r * 0.83; P * 0.001) and with cognition composite score (r * 0.68; P * 0.001). Moreover, MAGE was associated with the MMSE (P * 0.001) and cognition composite score (P * 0.001) independently of age, sex, BMI, waist-to-hip (WHR) ratio, drug intake, physical activity, mean arterial blood pressure, FPG, PPG, and A1C. CONCLUSIONS — MAGE during a daily period was associated with an impairment of cognitive functioning independent of A1C, FPG, and PPG. The present data suggest that inter-ventional trials in older patients with type 2 diabetes should target not only A1C, PPG, and FPG but also daily acute glucose swing

Regulation of local GTP availability controls RAC1 activity and cell invasion

Physiological changes in GTP levels in live cells have never been considered a regulatory step of RAC1 activation because intracellular GTP concentration (determined by chromatography or mass spectrometry) was shown to be substantially higher than the in vitro RAC1 GTP dissociation constant (RAC1-GTP Kd). Here, by combining genetically encoded GTP biosensors and a RAC1 activity biosensor, we demonstrated that GTP levels fluctuating around RAC1-GTP Kd correlated with changes in RAC1 activity in live cells. Furthermore, RAC1 co-localized in protrusions of invading cells with several guanylate metabolism enzymes, including rate-limiting inosine monophosphate dehydrogenase 2 (IMPDH2), which was partially due to direct RAC1-IMPDH2 interaction. Substitution of endogenous IMPDH2 with IMPDH2 mutants incapable of binding RAC1 did not affect total intracellular GTP levels but suppressed RAC1 activity. Targeting IMPDH2 away from the plasma membrane did not alter total intracellular GTP pools but decreased GTP levels in cell protrusions, RAC1 activity, and cell invasion. These data provide a mechanism of regulation of RAC1 activity by local GTP pools in live cells

Scoring and psychometric properties of the Eye-Drop Satisfaction Questionnaire (EDSQ), an instrument to assess satisfaction and compliance with glaucoma treatment

<p>Abstract</p> <p>Background</p> <p>The objective of this study was to ascertain the scoring and assess the psychometric properties of the Eye-Drop Satisfaction Questionnaire (EDSQ), a 43-item Patient-Reported Outcome instrument developed to assess patients' satisfaction and compliance with glaucoma treatment.</p> <p>Methods</p> <p>The EDSQ was administered during an observational, retrospective study to 184 French patients treated for glaucoma. The hypothesized structure, including six dimensions (patient-clinician relationship; patient experience; patient-treatment interaction; apprehension; patient knowledge; travel), was tested by assessing the internal consistency reliability (Cronbach's alpha) and construct-related validity (item convergent and discriminant validity). As unsatisfactory results were demonstrated, another structure was defined using a principal component analysis (PCA) combined with content of items. Psychometric properties of this new structure were assessed. Scores were compared between low, moderate and high compliance profile groups defined using data collected with the Travalert electronic device.</p> <p>Results</p> <p>Analyses were performed with the 169 patients who completed at least half of the EDSQ items. The hypothesized structure showed a Cronbach's alpha lower than 0.70 for four dimensions out of six and an overall poor construct-related validity (range of item-scale correlations: 0.00-0.68). The new structure obtained with the PCA included six dimensions: concern about treatment (five items); concern about disease (two items); satisfaction with patient-clinician relationship (five items); positive beliefs (three items); treatment convenience (three items); and self-declared compliance (three items). A score ranging from 0 to 100 was calculated for each dimension, with higher scores indicating more of the attribute referred to in the dimension. Internal consistency reliability was good (Cronbach's alpha greater than 0.70 for five dimensions). The structure offered good construct-related validity (range of item-scale correlations: 0.36-0.82). Ceiling effects of 21% and 49%, were observed for the satisfaction with patient-clinician relationship and self-declared compliance scores. Patients in low compliance profile group reported the lowest score for the satisfaction with patient-clinician relationship, positive beliefs, treatment convenience and self-declared compliance dimensions, and the highest score for the concern about treatment dimension.</p> <p>Conclusions</p> <p>The scoring of the EDSQ was developed and the questionnaire proved to have satisfactory psychometric properties. EDSQ scores showed a promising relationship to compliance profiles. The EDSQ could be used in future studies.</p

Author Correction: Regulation of local GTP availability controls RAC1 activity and cell invasion

Correction to "Regulation of local GTP availability controls RAC1 activity and cell invasion