587 research outputs found
Modified bathroom scale and balance assessment: a comparison with clinical tests
Frailty and detection of fall risk are major issues in preventive gerontology. A simple tool frequently used in daily life, a bathroom scale (balance quality tester: BQT), was modified to obtain information on the balance of 84 outpatients consulting at a geriatric clinic. The results computed from the BQT were compared to the values of three geriatric tests that are widely used either to detect a fall risk or frailty (timed get up and go: TUG; 10 m walking speed: WS; walking time: WT; one-leg stand: OS). The BQT calculates four parameters that are then scored and weighted, thus creating an overall indicator of balance quality. Raw data, partial scores and the global score were compared with the results of the three geriatric tests. The WT values had the highest correlation with BQT raw data (r = 0.55), while TUG (r = 0.53) and WS (r = 0.56) had the highest correlation with BQT partial scores. ROC curves for OS cut-off values (4 and 5 s) were produced, with the best results obtained for a 5 s cut-off, both with the partial scores combined using Fisher's combination (specificity 85 %: 0.48), and with the empirical score (specificity 85 %: 8). A BQT empirical score of less than seven can detect fall risk in a community dwelling population
Association of kidney function with inflammatory and procoagulant markers in a diverse cohort: A cross-sectional analysis from the Multi-Ethnic Study of Atherosclerosis (MESA)
Background: Prior studies using creatinine-based estimated glomerular filtration rate (eGFR) have found limited associations between kidney function and markers of inflammation. Using eGFR and cystatin C, a novel marker of kidney function, the authors investigated the association of kidney function with multiple biomarkers in a diverse cohort.
Methods: The Multi-Ethnic Study of Atherosclerosis consists of 6,814 participants of white, African-American, Hispanic, and Chinese descent, enrolled from 2000-2002 from six U.S.
communities. Measurements at the enrollment visit included serum creatinine, cystatin C, and six
inflammatory and procoagulant biomarkers. Creatinine-based eGFR was estimated using the fourvariable
Modification of Diet in Renal Disease equation, and chronic kidney disease was defined by an eGFR less than 60 mL/min/1.73 m2.
Results: Adjusted partial correlations between cystatin C and all biomarkers were statistically significant: C-reactive protein (r = 0.08), interleukin-6 (r = 0.16), tumor necrosis factor-a soluble
receptor 1 (TNF-aR1; r = 0.75), intercellular adhesion molecule-1 (r = 0.21), fibrinogen (r = 0.14), and factor VIII (r = 0.11; two-sided p less than 0.01 for all). In participants without chronic kidney disease,
higher creatinine-based eGFR was associated only with higher TNF-aR1 levels.
Conclusion: In a cohort characterized by ethnic diversity, cystatin C was directly associated with multiple procoagulant and inflammatory markers. Creatinine-based eGFR had similar associations with these biomarkers among subjects with chronic kidney disease.This research was supported by contracts N01-HC-95159 through N01-HC-95169 from the National Heart, Lung, and Blood Institute (NHLBI)
Infrared light excites cells by changing their electrical capacitance
Optical stimulation has enabled important advances in the study of brain function and other biological processes, and holds promise for medical applications ranging from hearing restoration to cardiac pace making. In particular, pulsed laser stimulation using infrared wavelengths >1.5 μm has therapeutic potential based on its ability to directly stimulate nerves and muscles without any genetic or chemical pre-treatment. However, the mechanism of infrared stimulation has been a mystery, hindering its path to the clinic. Here we show that infrared light excites cells through a novel, highly general electrostatic mechanism. Infrared pulses are absorbed by water, producing a rapid local increase in temperature. This heating reversibly alters the electrical capacitance of the plasma membrane, depolarizing the target cell. This mechanism is fully reversible and requires only the most basic properties of cell membranes. Our findings underscore the generality of pulsed infrared stimulation and its medical potential
Irreversible Pulmonary Hypertension Associated with the use of Interferon Alpha for Chronic Hepatitis C
The interferons are a complex group of virally induced proteins produced by activated macrophages and lymphocytes, which have become the mainstay of therapy for hepatitis C infection. Sustained viral response (SVR) rates in noncirrhotic patients vary from 40–80% with interferon-based therapy. This, along with transplantation, has drastically changed the course of hepatitis C virus (HCV) infection over the last two decades. Numerous side effects associated with interferon therapy have been reported. These range from transient flu-like symptoms to serious effects such as cardiac arrhythmias, cardiomyopathy, renal and liver failure, polyneuropathy, and myelosuppression. Pulmonary side effects including pneumonitis, pulmonary fibrosis, and reversible pulmonary hypertension have been reported. Herein, we present four cases in which irreversible pulmonary hypertension was diagnosed after prolonged treatment with interferon alpha. In each case, other causes of pulmonary hypertension were systematically eliminated. Pulmonary artery hypertension, which may be irreversible, should be considered in patients being treated with interferon alpha who present with exertional dyspnea and do not have a readily identifiable inflammatory or thromboembolic cause
Methods for specifying the target difference in a randomised controlled trial : the Difference ELicitation in TriAls (DELTA) systematic review
Peer reviewedPublisher PD
The impact of Loneliness on Healthcare Use in older people: evidence from a nationally representative cohort
Sequentially based analysis versus image based analysis of Intima Media Thickness in common carotid arteries studies - Do major IMT studies underestimate the true relations for cardio- and cerebrovascular risk?
<p>Abstract</p> <p>Background</p> <p>Image-based B-mode ultrasound has gained popularity in major studies as a non-invasive method of measuring cardio- and cerebrovascular risk factors. However, none of the major studies appears to have paid sufficient attention to the variation in end diastolic wall process. By using sequentially based analyses (SBA) of Intima-Media Thickness (IMT), the general purpose of this study was to show that the current image based (ECG tracked) analysis (IBA) has some major variations and might underestimate the true relations for cardiovascular events and stroke for IMT measurement.</p> <p>Method</p> <p>The study group consisted of 2500 healthy male subjects aged between 35 to 55 years. 4 sequences (300 images) were analyzed per subject. 750,000 images were analysed throughout the course of this study.</p> <p>Results</p> <p>IBA showed significantly lower mean, maximal, and minimal values for IMT in CCA than for SBA. The correlation analysis between IBA and SBA with the cardio- and cerebrovascular risk factors showed a higher correlation of SBA for all risk factors. The Pearson coefficient was 0.81, p < 0.01, for SBA versus Framingham CHD risk level (FCRL) and 0.49, p = 0.01, for IBA versus FCRL.</p> <p>Conclusion</p> <p>IBA did not measure the true maximal values of the IMT in this study. Together with the correlation analysis, this indicates that IBA might underestimate the true relations for IMT and risk factors.</p
Nicotinic Receptor Alpha7 Expression during Tooth Morphogenesis Reveals Functional Pleiotropy
The expression of nicotinic acetylcholine receptor (nAChR) subtype, alpha7, was investigated in the developing teeth of mice that were modified through homologous recombination to express a bi-cistronic IRES-driven tau-enhanced green fluorescent protein (GFP); alpha7GFP) or IRES-Cre (alpha7Cre). The expression of alpha7GFP was detected first in cells of the condensing mesenchyme at embryonic (E) day E13.5 where it intensifies through E14.5. This expression ends abruptly at E15.5, but was again observed in ameloblasts of incisors at E16.5 or molar ameloblasts by E17.5–E18.5. This expression remains detectable until molar enamel deposition is completed or throughout life as in the constantly erupting mouse incisors. The expression of alpha7GFP also identifies all stages of innervation of the tooth organ. Ablation of the alpha7-cell lineage using a conditional alpha7Cre×ROSA26-LoxP(diphtheria toxin A) strategy substantially reduced the mesenchyme and this corresponded with excessive epithelium overgrowth consistent with an instructive role by these cells during ectoderm patterning. However, alpha7knock-out (KO) mice exhibited normal tooth size and shape indicating that under normal conditions alpha7 expression is dispensable to this process. The function of ameloblasts in alpha7KO mice is altered relative to controls. High resolution micro-computed tomography analysis of adult mandibular incisors revealed enamel volume of the alpha7KO was significantly reduced and the organization of enamel rods was altered relative to controls. These results demonstrate distinct and varied spatiotemporal expression of alpha7 during tooth development, and they suggest that dysfunction of this receptor would have diverse impacts upon the adult organ
Handgrip performance in relation to self-perceived fatigue, physical functioning and circulating IL-6 in elderly persons without inflammation
BACKGROUND: Low grip strength is recognized as one of the characteristics of frailty, as are systemic inflammation and the sensation of fatigue. Contrary to maximal grip strength, the physical resistance of the muscles to fatigue is not often included in the clinical evaluation of elderly patients. The aim of this study was to investigate if the grip strength and the resistance of the handgrip muscles to fatigue are related to self-perceived fatigue, physical functioning and circulating IL-6 in independently living elderly persons. METHODS: Forty elderly subjects (15 female and 25 male, mean age 75 ± 5 years) were assessed for maximal grip strength, as well as for fatigue resistance and grip work (respectively time and work delivered until grip strength drops to 50% of its maximum during sustained contraction), self perceived fatigue (VAS-Fatigue, Mob-Tiredness scale and the energy & fatigue items of the WHOQOL-100), self rated physical functioning (domain of physical functioning on the MOS short-form) and circulating IL-6. Relationships between handgrip performance and the other outcome measures were assessed. RESULTS: In the male participants, fatigue resistance was negatively related to actual sensation of fatigue (VAS-F, p < .05) and positively to circulating IL-6 (p < .05). When corrected for body weight, the relations of fatigue resistance with self-perceived fatigue became stronger and also apparent in the female. Grip strength and grip work were significantly related with several items of self-perceived fatigue and with physical functioning. These relations became more visible by means of higher correlation coefficients when grip strength and grip work were corrected for body weight. CONCLUSION: Well functioning elderly subjects presenting less handmuscle fatigue resistance and weaker grip strength are more fatigued, experience more tiredness during daily activities and are more bothered by fatigue sensations. Body weight seems to play an important role in the relation of muscle performance to fatigue perception. Elderly patients complaining from fatigue should be physically assessed, both evaluating maximal grip strength and fatigue resistance, allowing the calculation of grip work, which integrates both parameters. Grip work might best reflect the functional capacity resulting from the development of a certain strength level in relation to the time it can be maintained
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