Female Sprague Dawley Rats Show Impaired Spatial Memory in the 8-Arm Radial Maze under Dim Blue and Red Light

Light intensity and wavelength strongly influence mood and cognition in humans and rodent animal models. The aim of the present study was to explore if dim white (7.6–17.7 lux) , blue (1.3–2.3 lux), and red light (0.8–1.4 lux) affect spatial memory of male and female Sprague Dawley rats in the 8-arm radial maze. Our data show that spatial memory significantly improved within 5 daily learning sessions (each 5 trials) under dim white light, which was not different between male and female rats. However, dim blue and red light significantly reduced spatial learning of female rats in the 8-arm radial maze in the last training session (session 5). In conclusion, we suggest that female Sprague Dawley rats show reduced learning under blue and red light

Performance Score (T2D)-A New Perspective in the Assessment of Six-Minute Walking Tests in Pulmonary Rehabilitation

Because absolute changes in outcomes are difficult to interpret and the minimal clinically important difference (MCID) is not suitable to address this challenge, a novel method of classifying outcomes by relating changes to baseline values is warranted. We used the "performance score" (T2D), which reflects individual performance, enabling us to consider the functional status at the beginning of rehabilitation without dealing with the problems of mathematical coupling or regression effects, as encountered in ANCOVA. To illustrate the T2D, we retrospectively analyzed changes in the six-minute walking test (6MWT) in COPD patients undergoing outpatient pulmonary rehabilitation and compared the results with absolute differences related to a predetermined MCID. We evaluated a total of 575 COPD patients with a mean age of 61.4 ± 9.2 years. 6MWT improved significantly, with a mean change of 32.3 ± 71.2. A total of 105/311 participants who had reached the MCID were still classified as "below average" by the T2D. Conversely, 76/264 patients who had not reached the MCID were classified as "above average". This new performance measure accounts for the patient's current status and for changes over time, potentially representing a simple and user-friendly tool that can be used to quantify a patient's performance and response to rehabilitation

Galactose Counteracts Hypoglycemia-Induced Decline of Cholinergic Neurons at Low pH in Organotypic Rat Brain Slices of the Basal Nucleus of Meynert

A growing body of evidence indicates that hypoglycemia and acidosis may contribute to the development of Alzheimer’s disease (AD). The cell death of basal forebrain cholinergic neurons constitutes a hallmark of AD and directly correlates with cognitive impairment. The aim of the present study was to investigate, in an organotypic rat brain slice model of the basal nucleus of Meynert, the effects of glucose deprivation on cholinergic neurons under normal and acidic conditions. Furthermore, we were interested to explore whether different saccharides (galactose, fructose, saccharose, lactose) can replace glucose under low pH conditions. Our data show a pH-dependent survival of cholinergic neurons at a high (37.1 mmol/l) glucose level, which was markedly decreased at a low (5.6 mmol/l) glucose level. Galactose (+31.5 mmol/l) significantly counteracted the loss of choline acetyltransferase-positive neurons in low-glucose-treated slices, while fructose, lactose and saccharose only partly protected cholinergic neurons. In conclusion, our results indicate that replacement of glucose with different saccharides, but most potently with galactose, protects cholinergic neurons against hypoglycemia at a low pH.</jats:p

Ethanol transiently suppresses choline-acetyltransferase in basal nucleus of Meynert slices

AbstractThe cholinergic system plays a major role in learning and cognition and cholinergic neurons appear to be particularly vulnerable to ethanol (EtOH) exposure. There are conflicting results if EtOH directly damages cholinergic neurons. Thus, the aims of the present study were (1) to investigate the effect of different EtOH concentrations on cholinergic neurons in organotypic brain slices of the nucleus basalis of Meynert (nbM) and (2) to study if the most potent cholinotrophic substance nerve growth factor (NGF) or inhibitors of mitogen activated kinase (MAPK) p38- and nitric-oxide synthase (NOS)-pathways may counteract any EtOH effect. Two-week old organotypic rat brain slices of the nbM were exposed to 1–100mM EtOH for 7days with or without drugs and the number of choline-acetyltransferase (ChAT)-positive neurons was counted. Our data show that EtOH significantly reduced the number of ChAT-positive neurons with the most potent effect at a concentration of 50mM EtOH (54±5 neurons per slice, p<0.001), compared to control slices (120±13 neurons per slice). Inhibition of MAPK p38 (SB 203580, 10μM) and NOS (L-thiocitrulline, 10μM) counteracted the EtOH-induced decline of cholinergic neurons and NGF protected cholinergic neurons against the EtOH-induced effect. Withdrawal of EtOH resulted in a reversal of cholinergic neurons to nearly controls. In conclusion, EtOH caused a transient decline of cholinergic neurons, possibly involving MAPK p38- and NOS-pathways suggesting that EtOH does not induce direct cell death, but causes a transient downregulation of the cholinergic key enzyme, possibly reflecting a form of EtOH-associated plasticity

Inter-rater reliability of a newly developed gait analysis and motion score

Background: Gait analysis constitutes an essential part of orthopedic rehabilitation assessment. Previous studies indicate that observational-based gait analysis lacks reliability and requires extensive clinical training. Therefore, gait analysis in the clinical practice heavily relies on technical aids. The aim of the present study is to develop a reliable gait analysis assessment tool that can accurately assess clinically relevant gait cycle parameters in daily clinical practice. Methods: In this pilot study, a new gait analysis and motion score (GAMS), comprising 10 observational and 5 technically measured (e.g. pressure plate) gait parameters, was developed. The parameters were dichotomously operationalized, reflecting pathological versus physiological manifestations of the parameters. The rating algorithm was administered by 12 raters using videotaped treadmill sessions of 10 orthopedic subjects ( n = 120 ratings). Inter-rater reliability was calculated using the intraclass correlation coefficient (ICC) and the percentage of rating agreement. Results: The mean (standard deviation (SD)) GAMS ratings ranged from 10.0 (1.1) to 21.5 (1.3) points. The overall GAMS ICC was 0.98 (95% confidence interval (CI) 0.96–1.00), whereas the ICC of observational parameters alone was 0.97 (95% CI 0.93–0.99). The mean (SD) percentage of rating agreement was 86.1% (3.3%). For the observational parameters, the mean (SD) rating agreement was 82.5% (4.5%). Conclusion: This new GAMS shows excellent overall inter-rater reliability for a continuum of functional gait statuses. The new score may be an appropriate clinical tool to objectively evaluate patients’ gait patterns. Furthermore, the GAMS may find application as a clinician-reported outcome measure in orthopedic rehabilitation. Further studies are required to verify the validity and accuracy of the new GAMS and its functionality in assessing clinical changes in gait patterns. </jats:sec

Machine learning approaches to predict rehabilitation success based on clinical and patient-reported outcome measures

A common way to treat hip, knee or foot injuries is by conducting a corresponding physician-guided rehab over several weeks or even months. While health professionals are often able to estimate the treatment success beforehand to a certain extent based on their experience, it is scientifically still not clear to what extent relevant factors and circumstances explain or predict rehab outcomes. To this end, we apply modern machine learning techniques to a real-life dataset consisting of data from more than a thousand rehab patients (N = 1,047) and build models that are able to predict the rehab success for a patient upon treatment start. By utilizing clinical and patient-reported outcome measures (PROMs) from questionnaires, we compute patient-related clinical measurements (CROMs) for different targets like the range of motion of a knee, and subsequently use those indicators to learn prediction models. While we at first apply regression algorithms to estimate the rehab success in terms of percental admission and discharge value differences, we finally also utilize classification models to make predictions based on a three-classed grading scheme. Extensive evaluations for different treatment groups and targets show promising results with F-scores exceeding 65% that are able to substantially outperform baselines (by up to 40%) and thus show that machine learning can indeed be applied for better medical controlling and optimized treatment paths in rehab praxis. Future developments should include further relevant critical success criteria in the rehabilitation routine to further optimize the prognosis models for clinical practice

Associations between Patient-Reported and Clinician-Reported Outcome Measures in Patients after Traumatic Injuries of the Lower Limb

Both clinician-reported outcome measures (CROMs) measures and patient-reported outcome measures (PROMs) are applied to evaluate outcomes in rehabilitation settings. The previous data show only a low to moderate correlation between these measures. Relationships between functional performance measures (Clinician-Reported Outcome Measures, CROMs) and Patient-Reported Outcome Measures (PROMs) were analysed in rehabilitation patients with traumatic injuries of the lower limb. A cohort of 315 patients with 3 subgroups (127 hip, 101 knee and 87 ankle region) was analysed before and after 3 weeks of inpatient rehabilitation. All three groups showed significant improvements in PROMs with low to moderate effect sizes. Moderate to high effect sizes were found for CROMs. Correlation coefficients between CROMs and PROMs were low to moderate. The performance consistency between PROMs and CROMs ranged from 56.7% to 64.1%. In this cohort of rehabilitation patients with traumatic injuries, CROMs showed higher effect sizes than PROMs. When used in combination, patient-reported outcome and performance measures contribute to collecting complementary information, enabling the practitioner to make a more accurate clinical evaluation of the patient&rsquo;s condition