Classification characteristics of fine motor experts based on electroencephalographic and force tracking data.

The application of machine learning techniques provides a data-driven approach for a deeper understanding of the development and expressions of expertise. In extension to the common procedure of comparing experts' and novices' performances in expertise-domain-related tasks we applied conventional classification algorithms. We distinguished between tasks for each participant and between groups, i.e., experts or novices, based on electroencephalographic (EEG) activity patterns and force output variables during four different force modulation tasks. The tasks under investigation involved sinusoidal and steady force tracking tasks, which were performed with the left and right hand. Classification of tasks based on EEG patterns as well as force output was possible with high accuracy in novices and experts, whereas classification of group membership, i.e., experts or novices, was at chance level. In follow-up analyses, we found a high degree of individuality in the EEG patterns of the experts, implying the long-term development of specialized central processing during fine motor tasks in fine motor experts. Taken together, the results suggest that continuous practice in the work context leads to the development of a highly individual and task-specific central control pattern.

Classification of visuomotor tasks based on electroencephalographic data depends on age-related differences in brain activity patterns.

Classification of physiological data provides a data driven approach to study central aspects of motor control, which changes with age. To implement such results in real-life applications for elderly it is important to identify age-specific characteristics of movement classification. We compared task-classification based on EEG derived activity patterns related to brain network characteristics between older and younger adults performing force tracking with two task characteristics (sinusoidal; constant) with the right or left hand. We extracted brain network patterns with dynamic mode decomposition (DMD) and classified the tasks on an individual level using linear discriminant analysis (LDA). Next, we compared the models' performance between the groups. Studying brain activity patterns, we identified signatures of altered motor network function reflecting dedifferentiated and compensational brain activation in older adults. We found that the classification performance of the body side was lower in older adults. However, classification performance with respect to task characteristics was better in older adults. This may indicate a higher susceptibility of brain network mechanisms to task difficulty in elderly. Signatures of dedifferentiation and compensation refer to an age-related reorganization of functional brain networks, which suggests that classification of visuomotor tracking tasks is influenced by age-specific characteristics of brain activity patterns. In addition to insights into central aspects of fine motor control, the results presented here are relevant in application-oriented areas such as brain computer interfaces.

[Treatment of fibromyalgia syndrome with gamma-hydroxybutyrate : A randomized controlled study]. / Die Behandlung des Fibromyalgiesyndroms mit Gamma-Hydroxybuttersäure : Eine randomisierte, kontrollierte Studie.

BACKGROUND: The etiology of fibromyalgia syndrome is not yet fully understood. Current hypotheses suggest a potential role of gamma-hydroxybutyrate (GHB) in influencing endocrinological abnormalities in patients with fibromyalgia. OBJECTIVE: The aim of the study was to investigate whether low dose GHB as a growth-hormone releasing substance reduces pain intensity and improves depressive mood, physical impairment and sleep quality in outpatients with fibromyalgia. Additionally, adverse events were recorded. MATERIAL AND METHODS: The pilot study was conducted in the outpatient clinic for pain at the clinic for anesthesiology and surgical intensive care of the Charité Universitätsmedizin Berlin. In the study 25 female patients with fibromyalgia according to the criteria of the American College of Rheumatology were randomized into 2 groups. Over 15 weeks patients of the intervention group received 25 mg/kg body weight oral GHB before going to bed and were compared with a placebo control group. In addition, all patients participated in operant behavioral pain treatment in a group setting. Dependent variables were pain intensity, depressive mood, physical impairment and quality of sleep. RESULTS: There were no group differences in the course of pain intensity (p = 0.61), depressive mood (p = 0.16), physical impairment (p = 0.25) and quality of sleep (p = 0.44); however, all symptoms improved across the groups from pretherapy to posttherapy. Low dose GHB did not increase growth hormone blood concentrations. The number of adverse events that were reported more than two times was similar in both groups. DISCUSSION: Administration of low dose GHB did not yield clinical improvements in female outpatients with fibromyalgia. General improvement in the course of treatment may have resulted from operant behavioral pain therapy. Future studies on GHB should control hypothetical risk factors for identification of non-responders.

[Incidence of constipation in patients with outpatient opioid therapy]. / Auftreten von Obstipation bei Patienten mit ambulanter Opioidtherapie.

BACKGROUND: Constipation is a common complication in patients with opioid therapy. Additionally, patient-related risk factors also contribute to the development of constipation and these factors have to be integrated into an individualized treatment plan. OBJECTIVE: The aim of this study was to assess the incidence of constipation in patients with opioid therapy in an outpatient setting and to analyze the risk factors that contribute to the development of constipation. MATERIAL AND METHODS: This retrospective cohort study was conducted in two university affiliated outpatient departments at the Charité hospital in Berlin. The trial included all consecutively treated patients with opioid therapy of at least 4 weeks duration. The study was conducted from January 2013 to August 2013. Constipation was defined according to the Rome III criteria. RESULTS: Out of 1166 screened patients, altogether 171 patients were included with a median duration of opioid therapy of 5 years. The most common diagnoses were back pain, musculoskeletal pain and neuropathic pain. In 14% of the treated patients symptoms of constipation were detected and another 35% needed laxatives for symptom control resulting in an overall incidence of constipation of 49%. The remaining 51% of the patients did not use any laxatives and did not experience symptoms of constipation. Age and dosing of opioid therapy significantly increased the risk of consipation but duration of opioid therapy was not related to the incidence of constipation. DISCUSSION: The incidence of constipation in this population remains high although a relevant number of patients were intermittently free of symptoms without using laxatives. An individualized therapy plan and patient education seem to be important elements to control opioid-associated constipation.

High RBC labeling efficiency by controlling pretinning with the modified in vivo/in vitro labeling method.

OBJECTIVE: The image quality for gastrointestinal bleeding studies depends on the efficiency of red blood cell labeling. The in vitro technique has been used widely because of its high labeling efficiency. New data for the modified in vivo/in vitro method are lacking. This study reports on the high labeling efficiency that can be obtained with the modified in vivo/in vitro method and the pitfalls to avoid. METHODS: A consecutive series of 91 labeling studies was analyzed. Different amounts of tin, red blood cell concentrations, and infusions of interfering substances also were studied. RESULTS: A mean efficiency of red blood cell labeling of 97% (80%-99%) was obtained. Only 3 cases showed unacceptable results. Suboptimal results were obtained with amounts of tin below 10 microg SnCl2/kg body weight, a reduced hematocrit, and blood transfusion or infusion of HES solution during pretinning. CONCLUSION: The modified in vivo/in vitro red blood cell labeling technique is performed easily, is useful and is comparable to the gold standard in vitro method, provided that the pretinning period is controlled carefully.

Total and free triiodothyronine in euthyroid individuals: the ambivalent influence of albumin in advanced age.

As T3 thyrotoxicosis may be difficult to be assessed in the low T3 syndrome and in advanced age, the matrix influence on different T3 parameters was evaluated in identical serum specimens of euthyroid non critically ill patients aged up to 95. The values obtained by the conventional TT3 RIA and the FT3 analog single step method with known albumin interference showed a strong relation to age (r = 0.4877 and r = 0.6929, respectively; both p < 0.001). Free T3 measurement by a labeled monoclonal antibody technique was independent of age effects (r = 0.0324, p = 0.748). Upon analyzing the binding parameters, albumin decreased with age and correlated closely with the age dependent T3 parameters (TT3: r = 0.6610, apparent FT3 by analog: r = 0.7664; both p < 0.001). In identical specimens, FT3 obtained by labeled monoclonal antibody is not influenced by albumin changes (r = 0.1986, p = 0.063). Consequently, TT3 cannot exactly predict the thyrometabolic status without corrections regarding binding protein variation including albumin, which is the underlying cause of the age dependence. The FT3 assay using labeled monoclonal antibody represents a precise and convenient technique and gives reliable results independent of changes of binding protein.

[The diagnosis of clinically silent thyroid disorders]. / Erkennung klinisch nicht vermuteter thyreoidaler Dysfunktion.

Results of tests for thyroid function are presented in two equal observation periods. Compared with the first the frequency of TSH-determinations was doubled in the second period. Data were taken from non-selected in-patients in a general hospital. In connection to clinical information TSH determination served as the first laboratory test. Prevalence data of hyperthyroid and hypothyroid dysfunction in the patients observed are given. According to controversies in health care the efficiency and efficacy of thyroid function tests are discussed. In an iodine deficient area TSH-determination uncovers many more thyroid dysfunctions in elderly patients than expected clinically. Screening of this risk group with TSH in connection with clinical information is an adequate diagnostic procedure in an area of mild iodine deficiency.

Plasma exchange and hemoperfusion in iodine-induced thyrotoxicosis.

Iodine-induced thyrotoxicosis is a life-threatening disease. Plasma exchange and hemoperfusion are the available means of detoxication. Both methods were applied repeatedly to 4 patients with iodine-induced thyrotoxicosis, and the efficacy of these treatment methods was compared. Thyroxine plasma levels were decreased by 33%, while the calculated body stores were reduced by 18% during plasma exchange. Hemoperfusion was less effective. With both methods, a rebound of plasma levels was seen. Improvement of the clinical condition was delayed for 1 week after discontinuation of treatment. One patient died, probably because detoxication was discontinued too soon after the thyroid hormone levels had normalized. Plasma exchange by using albumin (120 g/4,000 ml = 30 g/l) as replacement fluid is superior to that by using fresh-frozen plasma (2,000 ml/4,000 ml), since less thyroxine is administered (19 vs. 160 nmol).

Further evidence concerning motivational distortion on the Sixteen Personality Factor primaries by male felons.

A multiple regression analysis was used to determine the susceptibility of the 16 Personality Factor Test (16PF) to faking for a sample of male felons. The study is a replication of an earlier study of a similar sample. Motivational distortion (MD) correlated significantly with the 16PF primary scores. The relationship was most evident when the structure coefficients rather than the beta weights were analyzed. The findings were consistent with the previous results which indicated a fairly high degree of support for the MD corrections provided in the manual. An important exception was that Dominance (E) was suppressed by individuals from both samples when MD was present.

[Facial pain--dysfunction of the neck joints]. / Gesichtsschmerz--Dysfunktion der Kopfgelenke.

The etiopathogenesis of headache (cephalalgia) is multifactorial and has not been definitely clarified yet. One of the most frequent causes of this type of pain are disorders in the area of the neck joints such as locking of joints in passive or active movements or conditions affecting the segmentally arranged muscles. Manual mobilization of the affected joint structures or, possibly, a therapeutic nerve block is the most helpful treatment measure.

Comparing 16 PF scores for two groups of offenders.

The 16 PF scores for 678 male offenders in a diagnostic and receiving center were compared with scores for 891 male offenders in penal institutions by t tests for independent means. Significant differences were obtained for 13 of the 16 primaries included in the 16 PF. The Penitentiary group scored significantly higher than the Reception Center group on the primaries, A, I, L, M, O, Q1, and Q4. Conversely, the Reception Center group scored significantly higher than the Penitentiary group on the primaries, B, C, F, G, N, and Q3.

[Ultrahistochemical demonstration of blood group B substances on human erythrocytes with a lectin from Salmo gairdneri RICH]. / Ultrahistochemischer Nachweis der Blutgruppensubstanz B menschlicher Erythrocyten mit einem Lectin aus Salmo gairdneri RICH.

From the roe of Salmo gairdneri RICH., a lectin was isolated which agglutinates specifically human erythrocytes of blood group B. For cytochemical labelling of the blood group substance B on the surface of human erythrocytes, an indirect approach was chosen. By means of a polyclonal antibody from the rabbit against the B-specific fish lectin, electronmicroscopic presentation was performed with Protein A gold using a multistep method. For quantification gold labelling was partially followed by a silver technique.