How accurately does a simulation glove reflect function compared to rheumatoid arthritis sufferers?

INTRODUCTION

This study assessed the ability of gloves to simulate rheumatoid arthritis of the hand.

SUBJECTS AND METHODS

Assessments were made in the dominant hand of 24 healthy volunteers with no glove, glove A (simulating stiffness only) and glove B (simulating stiffness and pain). Results were compared to data held on 23 rheumatoid arthritis patients. Sollerman score was used as a standardised measure of hand function and time taken to complete testing was recorded. Grip strength was also measured in volunteers.

RESULTS

Both gloves simulate a reduction in power and prolong time taken to complete Sollerman hand-function testing. The gloves are less able to simulate a matched reduction in function when compared to rheumatoid arthritis sufferers. Sollerman score is 9.7% less in rheumatoid arthritis hands than a healthy volunteer using the glove.

CONCLUSIONS

The glove could, therefore, be used to guide future design of tools and aides that accommodate for hand disorders. More work on the usefulness of such disease simulation in the design of tools for such patients is needed.

Assessing falls in the elderly: should we use simple screening tests or a comprehensive fall risk evaluation?

The risk for falling increases in the older population, resulting in an increase in serious outcomes and associated health care costs. Incorporating a falls assessment measure into the routine clinical evaluation is important for early identification of elders who are at greater risk for falls and provide information that can guide interventions. This article reviews a sample of available falls assessment approaches that are targeted to community dwelling older adults, ranging from simple questionnaires to more functional-based assessments. Newer high-tech and laboratory-based procedures still under development also are discussed. Finally, additional factors related to older individuals, specifically cognition- and emotion-based features that can impact falls risk are discussed as related to their importance for consideration in routine falls assessments. This paper summarizes information to help guide the clinician in choosing the most appropriate currently available tool. As many of these measures are similar in their sensitivity and specificity, decisions on which approach to take in many cases may have to be informed also by the clinic setting and existing resources available to the clinician.

Revascularisation of coronary artery disease in patients with diabetes mellitus

Diabetes mellitus is becoming increasingly prevalent and magnifies the risk of cardiovascular complications. Endothelial dysfunction caused by oxidative stress is a hallmark of diabetes and is responsible for the ubiquitous manifestations of vascular disease in diabetics. Compared with non-diabetic patients, coronary artery disease is more severe and the clinical outcome impaired in diabetic patients undergoing revascularisation. Despite these limitations the benefit of revascularisation therapy is particularly pronounced in diabetics. The optimal revascularisation strategy (coronary artery bypass graft surgery versus percutaneous coronary intervention) in diabetic patients with coronary artery disease depends on clinical and anatomical considerations.

250 microg or 500 microg interferon beta-1b versus 20 mg glatiramer acetate in relapsing-remitting multiple sclerosis: a prospective, randomised, multicentre study

BACKGROUND

The aim of the Betaferon Efficacy Yielding Outcomes of a New Dose (BEYOND) trial was to compare the efficacy, safety, and tolerability of 250 microg or 500 microg interferon beta-1b with glatiramer acetate for treating relapsing-remitting multiple sclerosis.

METHODS

Between November, 2003, and June, 2005, 2447 patients with relapsing-remitting multiple sclerosis were screened and 2244 patients were enrolled in this prospective, multicentre, randomised trial. Patients were randomly assigned 2:2:1 by block randomisation with regional stratification to receive one of two doses of interferon beta-1b (250 microg or 500 microg) subcutaneously every other day or 20 mg glatiramer acetate subcutaneously every day. The primary outcome was relapse risk, defined as new or recurrent neurological symptoms separated by at least 30 days from the preceding event and that lasted at least 24 h. Secondary outcomes were progression on the expanded disability status scale (EDSS) and change in T1-hypointense lesion volume. Clinical outcomes were assessed quarterly for 2.0-3.5 years; MRI was done at screening and annually thereafter. Analysis was by per protocol. This study is registered, number NCT00099502.

FINDINGS

We found no differences in relapse risk, EDSS progression, T1-hypointense lesion volume, or normalised brain volume among treatment groups. Flu-like symptoms were more common in patients treated with interferon beta-1b (p<0.0001), whereas injection-site reactions were more common in patients treated with glatiramer acetate (p=0.0005). Patient attrition rates were 17% (153 of 888) on 250 microg interferon beta-1b, 26% (227 of 887) on 500 microg interferon beta-1b, and 21% (93 of 445) for glatiramer acetate.

INTERPRETATION

500 microg interferon beta-1b was not more effective than the standard 250 microg dose, and both doses had similar clinical effects to glatiramer acetate. Although interferon beta-1b and glatiramer acetate had different adverse event profiles, the overall tolerability to both drugs was similar.

FUNDING

Bayer HealthCare Pharmaceuticals.

Situational predictors of sexual risk episodes among men with HIV who have sex with men

BACKGROUND

Men with HIV who have sex with men (MSM) represent the largest group of people living with HIV/AIDS in the United States. It is important to understand the sexual risk-taking behaviours that may be linked to the transmission of HIV and other sexually transmitted infections in this population. Models of HIV risk that focus solely on personal factors have been demonstrated to be ineffective at explaining risk behaviour. Rather, in order to fully understand sexual risk-taking, it is important to examine the factors linked to high-risk sexual situations and not solely the factors linked to potentially high-risk people.

METHODS

A diverse sample of 100 MSM with HIV completed a 6-week internet-based sex diary that collected detailed information on recent sexual encounters. In total, information on over 250 sexual episodes was collected and analysed. Generalised linear mixed models were used to examine situational predictors of risk episodes.

RESULTS

Analyses revealed that drug use by self and sex partners (examined individually and together) were positively related to risk episodes. Likewise, having a sex partner met online and having a sexual encounter in a sex party or bathhouse setting was linked to risk episodes. Sexual episodes that involved a sex-partner who was perceived as sexually desirable and those involving communication about HIV and/or condom use with partners each were negatively related to risk.

CONCLUSIONS

Situational factors play an important role in explaining sexual risk-taking among MSM with HIV. Researchers should place a greater focus on drug use and characteristics of sex partners and settings in which sexual behaviours occur as situational predictors of risk in order to comprehensively understand sexual risk-taking in this population.

[Is resting heart rate a cardiovascular risk factor?]

During recent years, resting heart rate was not considered as a cardiovascular risk factor. However, new evidences have showed that resting heart rate is an important prognostic factor for sudden cardiac death and heart failure in the general population, and especially among patients with known cardiac disease. Interestingly, resting heart rate not only predicts cardiac mortality but also all-cause mortality. The most common pathophysiological explanation is related to the fact that increased heart rate increases myocardial oxygen consumption and in parallel reduces coronary blood flow (reduction in the diastolic duration).

Insulin resistance in mice lacking neuronal nitric oxide synthase is related to an alpha-adrenergic mechanism

BACKGROUND

nitric oxide (NO) plays an important role in the regulation of cardiovascular and glucose homeostasis. Mice lacking the gene encoding the neuronal isoform of nitric oxide synthase (nNOS) are insulin-resistant, but the underlying mechanism is unknown. nNOS is expressed in skeletal muscle tissue where it may regulate glucose uptake. Alternatively, nNOS driven NO synthesis may facilitate skeletal muscle perfusion and substrate delivery. Finally, nNOS dependent NO in the central nervous system may facilitate glucose disposal by decreasing sympathetic nerve activity.

METHODS

in nNOS null and control mice, we studied whole body glucose uptake and skeletal muscle blood flow during hyperinsulinaemic clamp studies in vivo and glucose uptake in skeletal muscle preparations in vitro. We also examined the effects of alpha-adrenergic blockade (phentolamine) on glucose uptake during the clamp studies.

RESULTS

as expected, the glucose infusion rate during clamping was roughly 15 percent lower in nNOS null than in control mice (89 (17) vs 101 (12) [-22 to -2]). Insulin stimulation of muscle blood flow in vivo, and intrinsic muscle glucose uptake in vitro, were comparable in the two groups. Phentolamine, which had no effect in the wild-type mice, normalised the insulin sensitivity in the mice lacking the nNOS gene.

CONCLUSIONS

insulin resistance in nNOS null mice was not related to defective insulin stimulation of skeletal muscle perfusion and substrate delivery or insulin signaling in the skeletal muscle cell, but to a sympathetic alpha-adrenergic mechanism.

Insulin resistance in mice lacking neuronal nitric oxide synthase is related to an alpha-adrenergic mechanism

BACKGROUND

nitric oxide (NO) plays an important role in the regulation of cardiovascular and glucose homeostasis. Mice lacking the gene encoding the neuronal isoform of nitric oxide synthase (nNOS) are insulin-resistant, but the underlying mechanism is unknown. nNOS is expressed in skeletal muscle tissue where it may regulate glucose uptake. Alternatively, nNOS driven NO synthesis may facilitate skeletal muscle perfusion and substrate delivery. Finally, nNOS dependent NO in the central nervous system may facilitate glucose disposal by decreasing sympathetic nerve activity.

METHODS

in nNOS null and control mice, we studied whole body glucose uptake and skeletal muscle blood flow during hyperinsulinaemic clamp studies in vivo and glucose uptake in skeletal muscle preparations in vitro. We also examined the effects of alpha-adrenergic blockade (phentolamine) on glucose uptake during the clamp studies.

RESULTS

as expected, the glucose infusion rate during clamping was roughly 15 percent lower in nNOS null than in control mice (89 (17) vs 101 (12) [-22 to -2]). Insulin stimulation of muscle blood flow in vivo, and intrinsic muscle glucose uptake in vitro, were comparable in the two groups. Phentolamine, which had no effect in the wild-type mice, normalised the insulin sensitivity in the mice lacking the nNOS gene.

CONCLUSIONS

insulin resistance in nNOS null mice was not related to defective insulin stimulation of skeletal muscle perfusion and substrate delivery or insulin signaling in the skeletal muscle cell, but to a sympathetic alpha-adrenergic mechanism.

Functional consequences of S1P receptor modulation in rat oligodendroglial lineage cells

Fingolimod (FTY720) and its phosphorylated form FTY720P are modulators of sphingosine-1-phosphate (S1P) receptors, which are G-protein coupled receptors linked to cell migration and vascular maturation. The efficacy of FTY720 in autoimmune diseases such as multiple sclerosis and its animal models has been attributed to its inhibition of lymphocyte trafficking to target organs. In this study, we examined the role of S1P receptors in cultured rat oligodendrocytes (OLGs) and OLG progenitor cells (OPCs) using the active phosphorylated form of FTY720. We found that (1) FTY720P improves the survival of neonatal rat OLGs during serum withdrawal, which is associated with the phosphorylation of extracellular signal regulated kinases (ERK1/2) and Akt; (2) FTY720P regulates OPC differentiation into OLGs in a concentration-dependent manner; and (3) S1P receptors are differentially modulated by platelet-derived growth factor (PDGF) resulting in downregulation of S1P5 and upregulation of S1P1 in OPCs. In addition, siRNA studies revealed that S1P1 participates in PDGF-induced OPC mitogenesis. We conclude that S1P1 and S1P5 serve different functions during oligodendroglial development, and possibly during remyelination.