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Voltage clamp experiments were performed on myelinated nerve fibres of Rana esculenta. The combined effects of increasing extracellular H concentration and lowering the Na concentration on sodium currents were studied. The presence of negative charges of two types at the external membrane surface could explain the observed shifts in the I- V curves and the reduction of I induced by H. Accordingly, from the data of shifts of the conductance voltage curves we calculate a density of −1 e/(20 Å) for unsepecific charges with an intrinsic pK=4.3. From the reduction of I induced by H we estimate a density of −1 e/Na channel for specific charges with an intrinsic pK=4.5. Na ions would bind to these specific charges when passing through the sodium channels and Na transport would be blocked if these groups are protonated. [ABSTRACT FROM AUTHOR]

This article cites a study assessing the effectiveness of continuous passive motion (CPM) after total knee arthroplasty (TKA). Data sources for the presents study were various previous studies that were identified by searching MEDLINE, EMBASE/Excerpta Medica, HealthSTAR, Sports Discus, CINAHL, the Cochrane Controlled Trials Register, and other information sources. The quality of each study was assessed with use of the 5-point Jadad scale. Data related to active and passive knee range of motion, length of hospital stay, pain, and quadriceps strength were gathered and compared. Based on findings of the study, it was concluded that CPM imporves active knee flexion and shortens hospital stay but does not affect other functional outcomes after TKA.

The Multifactorial Memory Questionnaire (MMQ; Troyer & Rich, [2002]. Psychometric properties of a new metamemory questionnaire for older adults. The Journals of Gerontology Series B: Psychological Sciences and Social Sciences , 57 (1), P19-P27) is a widely used measure of subjective memory consisting of three scales: Satisfaction, Ability, and Strategies. Although subjective memory complaints are prevalent across different age groups, the factor structure and psychometric properties of the MMQ have yet to be examined in young adults. Here, we independently replicated the original MMQ factor structure in N  = 408 young adults (YA) recruited from undergraduate courses and N  = 327 older adults (OA) and, for the first time, assessed the age-invariance of the scale using measurement invariance testing. YAs made significantly higher ratings than OAs on MMQ-Satisfaction and MMQ-Strategies, indicating greater satisfaction with their memory and greater use of strategies, but the groups were similar on MMQ-Ability. The original MMQ factor structure was replicated in OAs but not in YAs, and age invariance was not supported. Future studies seeking to compare young and older adults could therefore consider either requesting modification of the MMQ for use with young adults or using a different scale.

Chronic meningococcemia is defined by blood culture(s) positive for Neisseria meningitidis, symptoms duration > 7 days, and neither meningitis nor shock on admission. This series of 26 consecutive cases illustrates that this is a rare disease (< 5% of meningococcemia, < 0.05 cases per 100,000 inhabitants per year), mostly affecting young adults, males, with no predisposing condition. Major symptoms include fever, rash, and arthralgia. Median time between symptoms onset, and diagnosis is 28 days. Most patients fully recover with a 1-week course of parenteral betalactams.

It has previously been reported that priming a collectivistic social orientation (compared with an individualistic one) boosts object-location memory (Kühnen & Oyserman, 2002; Oyserman, Sorensen, Reber, & Chen, 2009). We conducted 4 experiments to replicate this reported effect, using the same methods as in those initial reports. In Experiment 1 (n = 145), we found a hint of a priming effect on object-location memory, but also an unanticipated interaction between priming and gender. In Experiment 2 (n = 90), we included gender as a formal factor and doubled the "dosage" of the priming, yet did not see any priming effects on memory. In Experiment 3 (n = 101), we octupled the priming "dosage" and again saw no significant effects on memory. Finally, in Experiment 4 (n = 102), we performed an exact replication of the methods of the original reports and again found no priming effects on memory. Any effects of this type of social orientation priming on object-location memory appear to be smaller and/or less robust than initially thought., ((c) 2015 APA, all rights reserved).)

Background: Wagner's Chronic Care Model (CCM), as well as the expanded version (ECCM) developed by Barr and colleagues, have been widely adopted as frameworks for prevention and management of chronic disease. Given the high prevalence of chronic illness in older persons, these frameworks can play a valuable role in reorienting the health care system to better serve the needs of seniors. We aimed to identify and assess the measured goals of E/CCM interventions in older populations. In particular, our objective was to determine the extent to which published E/CCM initiatives were evaluated based on population, community, system and individual-level outcomes (including clinical, functional and quality of life measures)., Methods: We conducted a systematic search of the Science Citation Index Web of Knowledge search tool to gather articles published between January 2003 and July 2014. We included published CCM interventions that cited at least one of the fundamental papers that introduced and described the CCM and ECCM. Studies retained for review reported evaluations of senior-focused E/CCM initiatives in community-based settings, with the topic of "older adults" OR senior* OR elder* OR geriatric OR aged. The resulting 619 published articles were independently reviewed for inclusion by two researchers. We excluded the following: systematic reviews, meta-analyses, descriptions of proposed programs, and studies whose populations did not focus on seniors., Results: We identified 14 articles that met inclusion criteria. Studies used a wide range of measures, with little consensus between studies. All of the included studies used the original CCM. While a range of system-level and individual patient outcomes have been used to evaluate CCM interventions, no studies employed measures of population or community health outcomes., Conclusions: Future efforts to test E/CCM interventions with seniors would be aided by more consistent outcome measures, greater attention to outcomes for the caregivers of older persons with chronic illness, and a greater focus on population and community impacts.

Whereas source memory involves remembering from whom you have heard something, destination memory involves remembering to whom you have told something. Despite its practical relevance, destination memory has been studied little. Recently, two reports suggested that generally destination memory should be poorer than source memory, and that it should be particularly difficult for older people. We tested these predictions by having young and older participants read sentences to two examiners (destination encoding) and listen to sentences read by two examiners (source encoding), under intentional (Experiment 1) or incidental encoding (Experiments 2 and 3). Only in Experiment 3 (in which cognitive demands during destination encoding were increased) was destination memory significantly poorer than source memory. In none of the experiments were older adults inferior to the young on destination or source memory. Destination- and source-memory scores were significantly correlated. Item memory was consistently superior for sentences that had been read out loud (during destination encoding) versus those that had been heard (during source encoding). Destination memory needs not always be poorer than source memory, appears not to be particularly impaired by normal ageing and may depend on similar processes to those supporting source memory.

Memory may be crucial for establishing and/or maintaining social bonds. Using the National Social life, Health, and Aging Project questionnaire, we examined close interpersonal relationships in three amnesic people: K.C. and D.A. (who are adult-onset cases) and H.C. (who has developmental amnesia). All three patients were less involved than demographically matched controls with neighbors and religious and community groups. A higher-than-normal percentage of the adult-onset (K.C. and D.A.) cases' close relationships were with family members, and they had made few new close friends in the decades since the onset of their amnesia. On the other hand, the patient with developmental amnesia (H.C.) had forged a couple of close relationships, including one with her fiancé. Social networks appear to be winnowed, but not obliterated, by amnesia. The obvious explanation for the patients' reduced social functioning stems from their memory impairment, but we discuss other potentially important factors for future study.

A growing array of synthetic bone regeneration scaffolds has been in use over the last century. These scaffolds aim to provide a three dimensional substrate for bone cells to populate on and to function appropriately. The majority of commercially-available scaffolds are based on calcium sulphate salts, calcium phosphate salts, or composites of the two. The mechanical and biological properties of these scaffolds are a result of the properties of the constituent materials and their ratio in the composite. This review addresses the mechanical and biological characteristics and provides an up-to-date summary of the clinical data available about the use of these calcium-based scaffolds. It will also assess the benefit of using stem cell technology along with this type of scaffolds. This article links between the basic science evidence and the clinical outcomes and details the commercially-available options.

Acoustic cell filters operate at high separation efficiencies with minimal fouling and have provided a practical alternative for up to 200 L/d perfusion cultures. However, the operation of cell retention systems depends on several settings that should be adjusted depending on the cell concentration and perfusion rate. The impact of operating variables on the separation efficiency performance of a 10-L acoustic separator was characterized using a factorial design of experiments. For the recirculation mode of separator operation, bioreactor cell concentration, perfusion rate, power input, stop time and recirculation ratio were studied using a fractional factorial 2(5-1) design, augmented with axial and center point runs. One complete replicate of the experiment was carried out, consisting of 32 more runs, at 8 runs per day. Separation efficiency was the primary response and it was fitted by a second-order model using restricted maximum likelihood estimation. By backward elimination, the model equation for both experiments was reduced to 14 significant terms. The response surface model for the separation efficiency was tested using additional independent data to check the accuracy of its predictions, to explore robust operation ranges and to optimize separator performance. A recirculation ratio of 1.5 and a stop time of 2 s improved the separator performance over a wide range of separator operation. At power input of 5 W the broad range of robust high SE performance (95% or higher) was raised to over 8 L/d. The reproducible model testing results over a total period of 3 months illustrate both the stable separator performance and the applicability of the model developed to long-term perfusion cultures., (Copyright (c) 2005 Wiley Periodicals, Inc.)

Objective: The objective of this metaanalysis is to examine the effectiveness of continuous passive motion (CPM) following total knee arthroplasty (TKA)., Methods: This metaanalysis used the methodology proposed by the Cochrane Collaboration., Results: This review of 14 studies (952 patients) found significant improvements in active knee flexion and analgesic use 2 weeks postoperatively with the use of CPM and physiotherapy (PT) compared to PT alone. In addition, length of hospital stay and need for knee manipulations were significantly decreased in the CPM group. Not enough data were available to compare the degree of knee flexion applied or number of hours of application of CPM. However, significant results were not found for other comparisons such as short term CPM application versus longterm CPM application and wide treatment range versus small treatment range for the outcomes of active knee flexion, passive knee flexion and extension, presence of a fixed flexion deformity, use of analgesic, or total knee range of motion., Conclusion: CPM combined with PT may offer beneficial results for patients post-TKA. However, the potential benefits will need to be carefully weighed against the inconvenience and expense of CPM. More research is necessary to assess the differences in effectiveness with different characteristics of application such as total duration of treatment and intensity of CPM interventions.

Background: Knee arthroplasty (KA) is a common intervention that can enhance the quality of life for patients with osteoarthritis (OA) and rheumatoid arthritis (RA). Post-surgery rehabilitation protocols often include continuous passive motion (CPM). However, CPM protocols vary considerably amongst institutions., Objectives: The purpose of the current meta-analysis is to evaluate the effectiveness of continuous passive motion following total knee arthroplasty., Search Strategy: An electronic search of MEDLINE (1966 to 2002), EMBASE (1988 to 2002), CINAHL (1982 to 2002), HEALTH STAR (1991 to 1994) and CURRENT CONTENTS (1997 to 2002) was conducted to identify randomized controlled trials., Selection Criteria: Following an a priori protocol, only randomized controlled trials of CPM for the treatment of participants post KA were eligible. Subjects were 18 years of age or older and had a pre-surgery diagnosis of degenerative joint disease. Both the experimental and control groups received physiotherapy. In addition to the physiotherapy intervention, the experimental group received CPM., Data Collection and Analysis: Two reviewers independently selected trials for inclusion. Data were then extracted and the quality of the trial assessed using predetermined forms. Outcome measures of interest were: active and passive knee range of motion (ROM) length of hospital stay, pain, swelling and quadriceps strength. A fixed effects model was used throughout for continuous variables, except where heterogeneity existed; in which case, a random effects model was used. Results were analyzed as weighted mean differences (WMD) with 95% confidence intervals (CI). Standardized mean differences (SMD) were used when different scales were used to measure the same concept (e.g. pain). Dichotomous outcomes were presented as a relative risk., Main Results: Fourteen trials were retained for analysis. Results favouring CPM were found for the main comparison of CPM combined with physiotherapy (PT) versus PT alone at end of treatment. For the primary outcomes of interest, CPM combined with PT was found to statistically significantly increase active knee flexion (WMD 4.30 degrees, 95% CI: 1.96, 6.63) and decrease length of stay (WMD -0.69 days, 95% CI: -1.35, -0.03). CPM was also found to decrease the need for post-operative manipulation (RR 0.12, 95% CI: 0.03, 0.53). CPM did not significantly improve passive knee flexion and passive or active knee extension., Reviewer's Conclusions: CPM combined with PT, may offer beneficial results compared to PT alone in the short term rehabilitation following total knee arthroplasty.

A new ion-selective liquid membrane microelectrode, based on the neutral carrier 1,1'-bis(2,3-naphtho-18-crown-6), is described that shows the dependence of EMF on the activity of divalent putrescine cations a(Put), with the linear slope s(Put) = 26 +/- 3 mV/decade (mean +/- SD, N = 18), in the range 10(-4)-10(-1) M at 25 +/- 1 degrees C. Values of potentiometric putrescine cation selectivity coefficients of logK(Pot)(Put) (j) (mean +/- SD, N) are obtained by the separate solution method for the ions K(+) (1.0 +/- 0.4, 10), Na(+) (-1.2 +/- 0.4, 8), Ca(2+) (-2.3 +/- 0.5, 10) and Mg(2+) (-2.5 +/- 0.5, 7). The microelectrode can be applied for the direct analysis of the activities of free divalent putrescine cations in the range 5 x 10(-4) to 10(-1) M in an extracellular ionic environment. Established analytical methods, e.g. high performance liquid chromatography, determine the total concentration of the derivatives of free and bound putrescine.

The aim of the present work was to study the action of clofibrate, known as peroxisomal proliferator, on the intestinal peroxisomes in the foetus of treated pregnant females. The Novikoff technique (catalase activity detection) shows an increase in the number and size of intestinal peroxisomes in the treated females and in the foetus. Significant differences were observed between enterocyte peroxisomal enzymatic activities (catalase and PBE: peroxisomal bifunctional enzyme) in treated and control females on the one hand, and in the foetus of treated and control mothers on the other. The ultrastructural immunocytochemical study of the PPAR (peroxisome proliferator activated receptor) shows labelling of the enterocyte nucleus and mitochondria by the gold particles.

Intra- and extracellular effects of the polyamine spermine on electrical activity and membrane currents of identified neurons in the abdominal ganglion of Aplysia californica were studied under current- and voltage-clamp conditions. Ionophoretic injection of spermine reduced the amplitude of action potentials and altered their time course as well as spontaneous discharge activity. Investigation of membrane currents showed that intracellular spermine suppressed the total outward current but increased the inward rectifier current. After separation of ion currents it was found that the voltage-activated, delayed K+ outward current and the Ca2+ inward current were reduced by intracellular spermine in a dose- and voltage-dependent manner. The block of the K+ current can be described by a voltage-dependent reaction, where one spermine molecule binds to one channel. The binding constant Kb, at zero voltage, and the effective valency, z delta, had values of 176/M and 0.41 for cell R-15, 223/M and 0.64 for cell L-11, and 137/M and 0.42 for cell L-3. Apparently, more than one spermine cation is needed to block one Ca2+ channel, since the coefficient n, which absorbs the molecularity and cooperativity of the reaction, had non-integral values between 1.34 and 2.22. The binding constant Kb and the effective valency z delta had values of 265/M and 0.64 for cell R-15, 82/M and 0.56 for cell L-4, and 263/M and 0.51 for cell L-6. Intracellular spermine also blocked the Ca(2+)-activated K+ current induced by ionophoretic Ca(2+)-injections, but increased the current at prolonged times after spermine injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Unlike other clinically used local anesthetics, carticaine contains a thiophene ring. Current voltage relations of peak sodium current INa and steady state potassium current IK were measured in voltage clamp experiments on the node of Ranvier of Rana esculenta. The dependence of the maximum sodium conductance on external concnetration of carticaine is described by an apparent dissociation constant KNa = 0.065 mM at pH = 7.3. An apparent dissociation constant KK = 0.147 mM at pH = 7.3 was calculated on the basis of the action of carticaine on the maximum potassium conductance. Similar to other amine local anesthetics, carticaine blocks sodium channels at a lower concentration than potassium channels, but lower concentrations of the thiophene derivative than of the benzene derivatives are needed to block the ionic channels. The partition coefficients in-octanol/Soerensen buffer at pH = 7.35 follow the sequence lidocaine (46) more than carticaine (17) more than procaine (2). Therefore, the action of these local anesthetics on sodium channels and potassium channels seems not to follow mere lipid solubility properties of the neutral drug. Increasing the pH from 6.3 to 8.3 favoured the neutral drug form and enhanced the block of both ionic channels but the relative reduction of the ionic currents was larger for potassium currents.

The action of the antituberculous agent ethambutol on the myelinated nerve was studied in two ways: (1) Resting and compound action potentials of the desheathed sciatic nerve were measured; (2) Na+ and K+ currents through the node of Ranvier were investigated by means of the voltage clamp. Reversible dose-dependent decreases of the compound action potential and of the conduction velocity were observed when ethambutol was applied in concentrations of 1--7 mM for 15 min; prolongation up to 60 min caused irreversible changes in membrane function and a decrease in Ca content. Ethambutol induced a hyperpolarizing change of the resting potential. When the nerve was depolarized in Ca2+-free solutions, ethambutol repolarized the nerve membrane. Ethambutol instantly reduced sodium and potassium currents through the nodal membrane. Presumably ethambutol acts primarily as a Ca2+ chelating cation on negative charges at the nerve membrane.