B-cell influences on the induction of allotype suppressor T cells

Allotype suppressor T-cell (Ts) populations that persist for the life of the animal arise in (BALB/c × SJL)F(1) hybrids exposed perinatally to antibody to the paternal (Ig-1b) allotype on IgG(2a)-isotype immunoglobulin H chains. These Ts suppress Ig-lb production by depleting the supply of allotype- specific helper T cells (Th) required, in addition to carrier-specific Th, for the latter stages of Ig-1b memory B-cell differentiation. In this publication, we show that specific Ig-1 allotype Ts are induced by perinatal exposure to antisera which interfere with normal B-cell maturation, i.e., by antibodies reactive with surface IgM on immature precursors of IgG(2a), memory cells. Antibodies to IgM (Ig-6) allotypes carried on precursors induce specific suppression for the IgG2, allotype produced by progeny of the target precursor. Anti-Ig-6a and anti-Ig-6b induce Ts that specifically suppress Ig-1a and Ig-1b, respectively. Heterologous (goat) anti-IgM induces suppression for both IgG(2a) immunoglobulins (Ig-1a and Ig-1b). Ts activity in these antiprecursor-Ig-suppressed mice is expressed in adoptive transfer assays and, as with anti-Ig-1b-induced Ts, is rendered ineffective by cotransfer of adequate numbers of T cells but not B cells from nonsuppressed mice. The Ts induction, in contrast with Ts expression, is reversed by the introduction of appropriate adult B-cell populations from nonsuppressed donors. Taken together, these data suggest that the development of mature B cells plays a central role in the early establishment of the balance between helper cells and suppressor cells that determines whether Ts or Th will dominate in regulating Ig-1b production in adult animals

Proxy reporting of health-related quality of life for people with dementia: a psychometric solution.

BACKGROUND: The growing move towards personalised health and social care systems means that every effort needs to be made to generate patient-reported outcome data. However, the deteriorating nature of dementia can make it difficult for people with dementia to complete self-reported questionnaires and it is often necessary to rely on a family member (proxy) to report on their behalf. There is little evidence to guide how the difference between self- and proxy-reports of health reported quality of life (HRQL) in dementia can be interpreted. METHODS: We recruited people with dementia and their family carers from 78 memory Assessment Services in the UK. We used Rasch measurement methods to investigate whether a HRQL questionnaire known as DEMQOL (self-reported by the person with dementia) and DEMQOL-Proxy (proxy-reported by a family carer) can be placed on the same continuum and whether a revised scoring algorithm, based on this equated model, can be developed that takes account of the relationship between self- and proxy-reports. RESULTS: In a sample of 1434 patients and 1030 carers, our findings supported equating DEMQOL/DEMQOL-Proxy (overall fit to the model; no mis-fitting items) after addressing specific issues (eight disordered items requiring re-scoring, four pairs locally dependent items, and five items showing DIF). Cross walk tables have been produced. CONCLUSIONS: We have established for the first time that DEMQOL and DEMQOL-Proxy can be placed on the same continuum and that patients and carer proxies are reporting on the same construct when they complete these questionnaires. Where possible both DEMQOL and DEMQOL-Proxy should still be administered together, using the improved scoring algorithm reported here. Where only DEMQOL-Proxy is available, the cross walk tables provide an estimate of DEMQOL for a particular person from their DEMQOL-Proxy score

Change in cardio-protective medication and health-related quality of life after diagnosis of screen-detected diabetes: Results from the ADDITION-Cambridge cohort.

AIMS: Establishing a balance between the benefits and harms of treatment is important among individuals with screen-detected diabetes, for whom the burden of treatment might be higher than the burden of the disease. We described the association between cardio-protective medication and health-related quality of life (HRQoL) among individuals with screen-detected diabetes. METHODS: 867 participants with screen-detected diabetes underwent clinical measurements at diagnosis, one and five years. General HRQoL (EQ5D) was measured at baseline, one- and five-years, and diabetes-specific HRQoL (ADDQoL-AWI) and health status (SF-36) at one and five years. Multivariable linear regression was used to quantify the association between change in HRQoL and change in cardio-protective medication. RESULTS: The median (IQR) number of prescribed cardio-protective agents was 2 (1 to 3) at diagnosis, 3 (2 to 4) at one year and 4 (3 to 5) at five years. Change in cardio-protective medication was not associated with change in HRQoL from diagnosis to one year. From one year to five years, change in cardio-protective agents was not associated with change in the SF-36 mental health score. One additional agent was associated with an increase in the SF-36 physical health score (2.1; 95%CI 0.4, 3.8) and an increase in the EQ-5D (0.05; 95%CI 0.02, 0.08). Conversely, one additional agent was associated with a decrease in the ADDQoL-AWI (-0.32; 95%CI -0.51, -0.13), compared to no change. CONCLUSIONS: We found little evidence that increases in the number of cardio-protective medications impacted negatively on HRQoL among individuals with screen-detected diabetes over five years.ADDITION-Cambridge was supported by the Wellcome Trust (grant reference No G061895) the Medical Research Council (grant reference no: G0001164), National Health Service R&D support funding (including the Primary Care Research and Diabetes Research Networks), and the National Institute for Health Research. We received an unrestricted grant from University of Aarhus, Denmark, to support the ADDITION-Cambridge trial. Bio-Rad provided equipment to undertake capillary glucose screening by HbA1c in general practice. The Primary Care Research Unit is supported by NIHR Research funds. SJG receives support from the Department of Health NIHR Programme Grant funding scheme (RP-PG-0606-1259). This article presents independent research funded by the NIHR under the Programme Grants for Applied Research programme (RP-PG-0606-1259]. The views expressed in this publication are those of the authors and not necessarily those of the NHS, the NIHR, or the Department of Health.This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.diabres.2015.04.01

Patient-reported outcomes: pathways to better health, better services, and better societies

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordWhile the use of PROs in research is well established, many challenges lie ahead as their use is extended to other applications. There is consensus that health outcome evaluations that include PROs along with clinician-reported outcomes and administrative data are necessary to inform clinical and policy decisions. The initiatives presented in this paper underline evolving recognition that PROs play a unique role in adding the patient perspective alongside clinical (e.g., blood pressure) and organizational (e.g., admission rates) indicators for evaluating the effects of new products, selecting treatments, evaluating quality of care, and monitoring the health of the population. In this paper, we first explore the use of PRO measures to support drug approval and labeling claims. We critically evaluate the evidence and challenges associated with using PRO measures to improve healthcare delivery at individual and population levels. We further discuss the challenges associated with selecting from the abundance of measures available, opportunities afforded by agreeing on common metrics for constructs of interest, and the importance of establishing an evidence base that supports integrating PRO measures across the healthcare system to improve outcomes. We conclude that the integration of PROs as a key end point within individual patient care, healthcare organization and program performance evaluations, and population surveillance will be essential for evaluating whether increased healthcare expenditure is translating into better health outcomes.Jose M. Valderas was supported by an NIHR Clinician Scientist Award (NIHR/CS/010/024)

Influence of dietary nitrate supplementation on physiological and muscle metabolic adaptations to sprint interval training

This is the author accepted manuscript. The final version is available from the American Physiological Society via the DOI in this record.We hypothesized that 4 wk of dietary nitrate supplementation would enhance exercise performance and muscle metabolic adaptations to sprint interval training (SIT). Thirty-six recreationally active subjects, matched on key variables at baseline, completed a series of exercise tests before and following a 4-wk period in which they were allocated to one of the following groups: 1) SIT and NO3--depleted beetroot juice as a placebo (SIT+PL); 2) SIT and NO3--rich beetroot juice (∼13 mmol NO3-/day; SIT+BR); or 3) no training and NO3--rich beetroot juice (NT+BR). During moderate-intensity exercise, pulmonary oxygen uptake was reduced by 4% following 4 wk of SIT+BR and NT+BR (P 0.05). The relative proportion of type IIx muscle fibers in the vastus lateralis muscle was reduced in SIT+BR only (P < 0.05). These findings suggest that BR supplementation may enhance some aspects of the physiological adaptations to SIT. NEW & NOTEWORTHY We investigated the influence of nitraterich and nitrate-depleted beetroot juice on the muscle metabolic and physiological adaptations to 4 wk of sprint interval training. Compared with placebo, dietary nitrate supplementation reduced the O2 cost of submaximal exercise, resulted in greater improvement in incremental (but not severe-intensity) exercise performance, and augmented some muscle metabolic adaptations to training. Nitrate supplementation may facilitate some of the physiological responses to sprint interval training.PepsiC

Muscle metabolic and neuromuscular determinants of fatigue during cycling in different exercise intensity domains.

This is the author accepted manuscript. The final version is available from American Physiological Society via the DOI in this record.The lactate or gas exchange threshold (GET) and the critical power (CP) are closely associated with human exercise performance. We tested the hypothesis that the limit of tolerance (Tlim) during cycle exercise performed within the exercise intensity domains demarcated by GET and CP is linked to discrete muscle metabolic and neuromuscular responses. Eleven males performed a ramp incremental exercise test, 4-5 severe-intensity (SEV; >CP) constant-work-rate (CWR) tests until Tlim, a heavy-intensity (HVY; GET) CWR test until Tlim, and a moderate-intensity (MOD; 0.05) muscle metabolic milieu (i.e., low pH and [PCr] and high [lactate]) was attained at Tlim (~2-14 min) for all SEV exercise bouts. The muscle metabolic perturbation was greater at Tlim following SEV compared to HVY, and also following SEV and HVY compared to MOD (all P0.05). Neural drive to the VL increased during SEV (4±4%; P0.05). During SEV and HVY, but not MOD, the rates of change in M-wave amplitude and neural drive were correlated with changes in muscle metabolic ([PCr], [lactate]) and blood ionic/acid-base status ([lactate], [K(+)]) (P<0.05). The results of this study indicate that the metabolic and neuromuscular determinants of fatigue development differ according to the intensity domain in which the exercise is performed

Dynamics of the power-duration relationship during prolonged endurance exercise and influence of carbohydrate ingestion

This is the author accepted manuscript. The final version is available from the American Physiological Society via the DOI in this recordWe tested the hypotheses that the parameters of the power-duration relationship, estimated as the end-test power (EP) and work done above EP (WEP) during a 3-min all out exercise test (3MT), would be reduced progressively following 40 min, 80 min and 2 h of heavy-intensity cycling, and that carbohydrate (CHO) ingestion would attenuate the reduction in EP and WEP. Sixteen participants completed a 3MT without prior exercise (control), immediately after 40 min, 80 min and 2-h of heavy-intensity exercise while consuming a placebo beverage, and also after 2-h of heavy-intensity exercise while consuming a CHO supplement (60 g/h CHO). There was no difference in EP measured without prior exercise (260 ± 37 W) compared to EP following 40 min (268 ± 39 W) or 80 min (260 ± 40 W) of heavy-intensity exercise; however, after 2-h, EP was 9% lower compared to control (236 ± 47 W; P<0.05). There was no difference in WEP measured without prior exercise (17.9 ± 3.3 kJ) compared to after 40 min of heavy-intensity exercise (16.1 ± 3.3 kJ), but WEP was lower (P<0.05) than control after 80 min (14.7 ± 2.9 kJ) and 2-h (13.8 ± 2.7 kJ). Compared to placebo, CHO ingestion negated the reduction of EP following 2-h of heavy-intensity exercise (254 ± 49 W) but had no effect on WEP (13.5 ± 3.4 kJ). These results reveal a different time course for the deterioration of EP and WEP during prolonged endurance exercise and indicate that EP is sensitive to CHO availability

Which activities threaten independent living of elderly when becoming problematic : inspiration for meaningful service robot functionality

Purpose: In light of the increasing elderly population and the growing demand for home care, the potential of robot support is given increasing attention. In this paper, an inventory of activities was made that threaten independent living of elderly when becoming problematic. Results will guide the further development of an existing service robot, the Care-O-bot®. Method: A systematic literature search of PubMed was performed, focused on the risk factors for institutionalization. Additionally, focus group sessions were conducted in the Netherlands, United Kingdom and France. In these focus group sessions, problematic activities threatening the independence of elderly people were discussed. Three separate target groups were included in the focus group sessions: (1) elderly persons (n = 41), (2) formal caregivers (n = 40) and (3) informal caregivers (n = 32). Results: Activities within the International Classification of Functioning domains mobility, self-care, and interpersonal interaction and relationships were found to be the most problematic. Conclusions: A distinct set of daily activities was identified that may threaten independent living, but no single activity could be selected as the main activity causing a loss of independence as it is often a combination of problematic activities that is person-specific. Supporting the problematic activities need not involve a robotic solution Read More: http://informahealthcare.com/doi/abs/10.3109/17483107.2013.840861Peer reviewe

Pain assessment for people with dementia: a systematic review of systematic reviews of pain assessment tools.

BACKGROUND: There is evidence of under-detection and poor management of pain in patients with dementia, in both long-term and acute care. Accurate assessment of pain in people with dementia is challenging and pain assessment tools have received considerable attention over the years, with an increasing number of tools made available. Systematic reviews on the evidence of their validity and utility mostly compare different sets of tools. This review of systematic reviews analyses and summarises evidence concerning the psychometric properties and clinical utility of pain assessment tools in adults with dementia or cognitive impairment. METHODS: We searched for systematic reviews of pain assessment tools providing evidence of reliability, validity and clinical utility. Two reviewers independently assessed each review and extracted data from them, with a third reviewer mediating when consensus was not reached. Analysis of the data was carried out collaboratively. The reviews were synthesised using a narrative synthesis approach. RESULTS: We retrieved 441 potentially eligible reviews, 23 met the criteria for inclusion and 8 provided data for extraction. Each review evaluated between 8 and 13 tools, in aggregate providing evidence on a total of 28 tools. The quality of the reviews varied and the reporting often lacked sufficient methodological detail for quality assessment. The 28 tools appear to have been studied in a variety of settings and with varied types of patients. The reviews identified several methodological limitations across the original studies. The lack of a 'gold standard' significantly hinders the evaluation of tools' validity. Most importantly, the samples were small providing limited evidence for use of any of the tools across settings or populations. CONCLUSIONS: There are a considerable number of pain assessment tools available for use with the elderly cognitive impaired population. However there is limited evidence about their reliability, validity and clinical utility. On the basis of this review no one tool can be recommended given the existing evidence