Impaired verbal memory in Parkinson disease: relationship to prefrontal dysfunction and somatosensory discrimination

OBJECTIVE: To study the neurocognitive profile and its relationship to prefrontal dysfunction in non-demented Parkinson's disease (PD) with deficient haptic perception. METHODS: Twelve right-handed patients with PD and 12 healthy control subjects underwent thorough neuropsychological testing including Rey complex figure, Rey auditory verbal and figural learning test, figural and verbal fluency, and Stroop test. Test scores reflecting significant differences between patients and healthy subjects were correlated with the individual expression coefficients of one principal component, obtained in a principal component analysis of an oxygen-15-labeled water PET study exploring somatosensory discrimination that differentiated between the two groups and involved prefrontal cortices. RESULTS: We found significantly decreased total scores for the verbal learning trials and verbal delayed free recall in PD patients compared with normal volunteers. Further analysis of these parameters using Spearman's ranking correlation showed a significantly negative correlation of deficient verbal recall with expression coefficients of the principal component whose image showed a subcortical-cortical network, including right dorsolateral-prefrontal cortex, in PD patients. CONCLUSION: PD patients with disrupted right dorsolateral prefrontal cortex function and associated diminished somatosensory discrimination are impaired also in verbal memory functions. A negative correlation between delayed verbal free recall and PET activation in a network including the prefrontal cortices suggests that verbal cues and accordingly declarative memory processes may be operative in PD during activities that demand sustained attention such as somatosensory discrimination. Verbal cues may be compensatory in nature and help to non-specifically enhance focused attention in the presence of a functionally disrupted prefrontal cortex.

Does subjective burden of early breast cancer and its treatment affect immune measures during adjuvant therapy?

Psychosocial factors have been described as affecting cellular immune measures in healthy subjects. In patients with early breast cancer we explored bi-directional psycho-immune effects to determine whether subjective burden has an impact on immune measures, and vice versa. Patients (n = 239) operated for early breast cancer and randomized into International Breast Cancer Study Group (IBCSG) adjuvant clinical trials were assessed immediately before the beginning of adjuvant treatment (baseline) and 3 and 6 months thereafter, at the beginning of the corresponding treatment cycle. Cellular immune measures (leukocytes, lymphocytes, lymphocyte subset counts), markers of activation of the cellular immune system (beta2-microglobulin, soluble interleukin-2 receptor serum levels), and self-report subjective burden (global indicators of physical well-being, mood, coping effort) were assessed concurrently. The relationship between subjective burden and gradients of immune measures was investigated with regression analyses controlling for adjuvant treatment. There was a pattern of small negative associations between all variables assessing subjective burden before the beginning of adjuvant therapy with the gradients of the markers of activation of the cellular immune system and NK cell counts. In particular, better mood predicted a decline in the course of beta2-microglobulin and IL-2r at months 3 and 6. The gradient of beta2-microglobulin was associated with mood and coping effort at month 3. However, the effect sizes were very small. In conclusion, in this explorative investigation, there was an indication for subjective burden affecting and being affected by markers of activation of the cellular immune system during the first 3 and 6 months of adjuvant therapy. The question of clinical significance remains unanswered. These associations have to be investigated with refined assessment tools and schedules.

Eccentric exercise in coronary patients: central hemodynamic and metabolic responses

With lengthening (eccentric) muscle contractions, the magnitude of locomotor-muscle mass and strength increase has been demonstrated to be greater compared with shortening (concentric) muscle contractions. In healthy subjects, energy demand and heart rate responses with eccentric exercise are small relative to the amount of muscle force produced. Thus, eccentric exercise may be an attractive alternative to resistance exercise for patients with limited cardiovascular exercise tolerance.

Subsecond changes of global brain state in illusory multistable motion perception

This study explored transient changes in EEG microstates and spatial Omega complexity associated with changes in multistable perception. 21-channel EEG was recorded from 13 healthy subjects viewing an alternating dot pattern that induced illusory motion with ambiguous direction. Baseline epochs with stable motion direction were compared to epochs immediately preceding stimuli that were perceived with changed motion direction ('reference stimuli'). About 750 ms before reference stimuli, Omega complexity decreased as compared to baseline, and two of four classes of EEG microstates changed their probability of occurrence. About 300 ms before reference stimuli, Omega complexity increased and the previous deviations of EEG microstates were reversed. Given earlier results on Omega complexity and microstates, these sub-second EEG changes might parallel longer-lasting fluctuations in vigilance. Assumedly, the discontinuities of illusory motion thus occur during sub-second dips in arousal, and the following reconstruction of the illusion coincides with a state of relative over-arousal.

Analysis of eye and head coordination in a visual peripheral recognition task

Coordinated eye and head movements simultaneously occur to scan the visual world for relevant targets. However, measuring both eye and head movements in experiments allowing natural head movements may be challenging. This paper provides an approach to study eye-head coordination: First, we demonstra- te the capabilities and limits of the eye-head tracking system used, and compare it to other technologies. Second, a beha- vioral task is introduced to invoke eye-head coordination. Third, a method is introduced to reconstruct signal loss in video- based oculography caused by cornea reflection artifacts in order to extend the tracking range. Finally, parameters of eye- head coordination are identified using EHCA (eye-head co- ordination analyzer), a MATLAB software which was developed to analyze eye-head shifts. To demonstrate the capabilities of the approach, a study with 11 healthy subjects was performed to investigate motion behavior. The approach presented here is discussed as an instrument to explore eye-head coordination, which may lead to further insights into attentional and motor symptoms of certain neurological or psychiatric diseases, e.g., schizophrenia.

Faces and emotions: brain electric field sources during covert emotional processing

Covert brain activity related to task-free, spontaneous (i.e. unrequested), emotional evaluation of human face images was analysed in 27-channel averaged event-related potential (ERP) map series recorded from 18 healthy subjects while observing random sequences of face images without further instructions. After recording, subjects self-rated each face image on a scale from “liked” to “disliked”. These ratings were used to dichotomize the face images into the affective evaluation categories of “liked” and “disliked” for each subject and the subjects into the affective attitudes of “philanthropists” and “misanthropists” (depending on their mean rating across images). Event-related map series were averaged for “liked” and “disliked” face images and for “philanthropists” and “misanthropists”. The spatial configuration (landscape) of the electric field maps was assessed numerically by the electric gravity center, a conservative estimate of the mean location of all intracerebral, active, electric sources. Differences in electric gravity center location indicate activity of different neuronal populations. The electric gravity center locations of all event-related maps were averaged over the entire stimulus-on time (450 ms). The mean electric gravity center for disliked faces was located (significant across subjects) more to the right and somewhat more posterior than for liked faces. Similar differences were found between the mean electric gravity centers of misanthropists (more right and posterior) and philanthropists. Our neurophysiological findings are in line with neuropsychological findings, revealing visual emotional processing to depend on affective evaluation category and affective attitude, and extending the conclusions to a paradigm without directed task.

Microvascular response to metabolic and pressure challenge in the human coronary circulation

In vivo observations of microcirculatory behavior during autoregulation and adaptation to varying myocardial oxygen demand are scarce in the human coronary system. This study assessed microvascular reactions to controlled metabolic and pressure provocation [bicycle exercise and external counterpulsation (ECP)]. In 20 healthy subjects, quantitative myocardial contrast echocardiography and arterial applanation tonometry were performed during increasing ECP levels, as well as before and during bicycle exercise. Myocardial blood flow (MBF; ml·min(-1)·g(-1)), the relative blood volume (rBV; ml/ml), the coronary vascular resistance index (CVRI; dyn·s·cm(-5)/g), the pressure-work index (PWI), and the pressure-rate product (mmHg/min) were assessed. MBF remained unchanged during ECP (1.08 ± 0.44 at baseline to 0.92 ± 0.38 at high-level ECP). Bicycle exercise led to an increase in MBF from 1.03 ± 0.39 to 3.42 ± 1.11 (P < 0.001). The rBV remained unchanged during ECP, whereas it increased under exercise from 0.13 ± 0.033 to 0.22 ± 0.07 (P < 0.001). The CVRI showed a marked increase under ECP from 7.40 ± 3.38 to 11.05 ± 5.43 and significantly dropped under exercise from 7.40 ± 2.78 to 2.21 ± 0.87 (both P < 0.001). There was a significant correlation between PWI and MBF in the pooled exercise data (slope: +0.162). During ECP, the relationship remained similar (slope: +0.153). Whereas physical exercise decreases coronary vascular resistance and induces considerable functional capillary recruitment, diastolic pressure transients up to 140 mmHg trigger arteriolar vasoconstriction, keeping MBF and functional capillary density constant. Demand-supply matching was maintained over the entire ECP pressure range.

The short-term treatment effects on the microbiota at the dorsum of the tongue in intra-oral halitosis patients-a randomized clinical trial

OBJECTIVES This study aims to assess the effects of rinsing with zinc- and chlorhexidine-containing mouth rinse with or without adjunct tongue scraping on volatile sulfur compounds (VSCs) in breath air, and the microbiota at the dorsum of the tongue. MATERIAL AND METHODS A randomized single-masked controlled clinical trial with a cross-over study design over 14 days including 21 subjects was performed. Bacterial samples from the dorsum of the tongue were assayed by checkerboard DNA-DNA hybridization. RESULTS No halitosis (identified by VSC assessments) at day 14 was identified in 12/21 subjects with active rinse alone, in 10/21 with adjunct use of tongue scraper, in 1/21 for negative control rinse alone, and in 3/21 in the control and tongue scraping sequence. At day 14, significantly lower counts were identified only in the active rinse sequence (p < 0.001) for 15/78 species including, Fusobacterium sp., Porphyromonas gingivalis, Pseudomonas aeruginosa, Staphylococcus aureus, and Tannerella forsythia. A decrease in bacteria from baseline to day 14 was found in successfully treated subjects for 9/74 species including: P. gingivalis, Prevotella melaninogenica, S. aureus, and Treponema denticola. Baseline VSC scores were correlated with several bacterial species. The use of a tongue scraper combined with active rinse did not change the levels of VSC compared to rinsing alone. CONCLUSIONS VSC scores were not associated with bacterial counts in samples taken from the dorsum of the tongue. The active rinse alone containing zinc and chlorhexidine had effects on intra-oral halitosis and reduced bacterial counts of species associated with malodor. Tongue scraping provided no beneficial effects on the microbiota studied. CLINICAL RELEVANCE Periodontally healthy subjects with intra-oral halitosis benefit from daily rinsing with zinc- and chlorhexidine-containing mouth rinse.

Effects of age and eccentricity on visual target detection

The aim of this study was to examine the effects of aging and target eccentricity on a visual search task comprising 30 images of everyday life projected into a hemisphere, realizing a ±90° visual field. The task performed binocularly allowed participants to freely move their eyes to scan images for an appearing target or distractor stimulus (presented at 10°; 30°, and 50° eccentricity). The distractor stimulus required no response, while the target stimulus required acknowledgment by pressing the response button. One hundred and seventeen healthy subjects (mean age = 49.63 years, SD = 17.40 years, age range 20–78 years) were studied. The results show that target detection performance decreases with age as well as with increasing eccentricity, especially for older subjects. Reaction time also increases with age and eccentricity, but in contrast to target detection, there is no interaction between age and eccentricity. Eye movement analysis showed that younger subjects exhibited a passive search strategy while older subjects exhibited an active search strategy probably as a compensation for their reduced peripheral detection performance.

A1.40 Adiponektin and resistin levels in pregnant patients with rheumatoid arthritis

BACKGROUND Pregnancy induces a modulation of the maternal immune system in order to install tolerance towards the semiallogeneic fetus. This change of the maternal immune systems influences some autoimmune diseases such as rheumatoid arthritis (RA) in a positive way. Our previous study showed that genes of the adipocytokine pathway were differently regulated by pregnancy as well as by RA. The objective of this study was to analyse the association between pregnancy induced improvement of RA and changes of adipocytokine levels. MATERIAL AND METHODS Adiponectin and resistin levels were measured in sera of pregnant (n = 29) and non-pregnant (n = 24) RA patients as well as in pregnant (n = 26) and non-pregnant (n = 9) healthy controls by ELISA. Pregnant RA patients were analysed before conception, once at each trimester and 8 weeks postpartum. Disease activity was measured by CRP and DAS28-CRP. RESULTS Resistin levels were higher in non-pregnant RA patients than in healthy controls. Resistin levels increased during pregnancy and decreased postpartum in both healthy subjects and RA patients. However, RA patients with active disease during pregnancy showed higher resistin levels at the third trimester than healthy women. There was a positive correlation between resistin levels and CRP. Adiponektin levels increased at the second trimester of pregnancy and decreased thereafter in both healthy subject and RA patients. There was no difference between patients and healthy subjects. Adiponektin levels of RA patients negatively correlated with CRP. CONCLUSION Pregnancy induces an increase of both the resistin and the adiponectin levels. Resistin levels are further influenced by active disease. By contrast, the increase of the adiponectin levels at the second trimester might play a role in the modulation of disease activity of RA.

Microbial communities in the respiratory tract of patients with interstitial lung disease

Background Molecular methods based on phylogenetic differences in the 16S rRNA gene are able to characterise the microbiota of the respiratory tract in health and disease. Objectives Our goals were (1) to characterise bacterial communities in lower and upper airways of patients with interstitial lung disease (ILD) and (2) to compare the results with the microbiota of patients with Pneumocystis pneumonia (PCP) and normal controls. Methods We examined the upper and lower respiratory tract of 18 patients with ILD of whom 5, 6, and 7 had idiopathic interstitial pneumonia (IIP), non-IIP and sarcoidosis, respectively. In addition, six immune-compromised patients with PCP and nine healthy subjects were included as controls. Exclusion criteria were recent bacterial/viral respiratory tract infection, HIV-positivity and subjects receiving antibiotic therapy. Bronchoalveolar lavage fluid and oropharyngeal swabs were simultaneously collected, and microbiota was characterised by ultra-deep 16S rRNA gene sequencing. Results The microbiota in lower airways of the majority of patients (30; 90%) primarily consisted of Prevotellaceae, Streptococcaceae and Acidaminococcaceae. α and β diversity measurements revealed no significant differences in airway microbiota composition between the five different groups of patients. Comparison of bacterial populations in upper and lower respiratory tract showed significant topographical discontinuities for 7 (23%) individuals. Conclusions IIP, non-IIP and sarcoidosis are not associated with disordered airway microbiota and a pathogenic role of commensals in the disease process is therefore unlikely. Nevertheless, molecular analysis of the topographical microbiota continuity along the respiratory tract may provide additional information to assist management of individual patients.

On the use of Cramér-Rao minimum variance bounds for the design of magnetic resonance spectroscopy experiments

Localized Magnetic Resonance Spectroscopy (MRS) is in widespread use for clinical brain research. Standard acquisition sequences to obtain one-dimensional spectra suffer from substantial overlap of spectral contributions from many metabolites. Therefore, specially tuned editing sequences or two-dimensional acquisition schemes are applied to extend the information content. Tuning specific acquisition parameters allows to make the sequences more efficient or more specific for certain target metabolites. Cramér-Rao bounds have been used in other fields for optimization of experiments and are now shown to be very useful as design criteria for localized MRS sequence optimization. The principle is illustrated for one- and two-dimensional MRS, in particular the 2D separation experiment, where the usual restriction to equidistant echo time spacings and equal acquisition times per echo time can be abolished. Particular emphasis is placed on optimizing experiments for quantification of GABA and glutamate. The basic principles are verified by Monte Carlo simulations and in vivo for repeated acquisitions of generalized two-dimensional separation brain spectra obtained from healthy subjects and expanded by bootstrapping for better definition of the quantification uncertainties.

Metabolic control in children and adolescents with diabetes mellitus type I in Berne: a cross-sectional study.

AIMS/HYPOTHESIS In diabetes mellitus type I, good glycaemic control is crucial in preventing long-term diabetic complications. The aim of this study was to determine the current level of metabolic control in children and adolescents in our diabetes outpatient clinic at the University Children's Hospital, Berne. Furthermore, the impact of different factors such as age, pubertal stage, sex, duration of diabetes and insulin regimen on glycaemic control was studied. METHODS In a cross-sectional, prospective study 168 children and adolescents with type I diabetes mellitus (f:m = 87:81; prepubertal 48 [mean age 4.4 years, mean duration of diabetes 2.8 years]; pubertal 120 [mean age 9.4 years; mean duration of diabetes 5.2 years]) were studied for three months. Clinical data and HbA1c levels (latex immunoagglutination test) were recorded, statistically analysed and compared with the international literature. RESULTS In our type I diabetic children and adolescents the overall HbA1c was 8.07 +/- 1.15% (mean +/- SD; test-specific norm for healthy subjects: 4.1-6.1%). Glycaemic control was significantly worse in the pubertal group compared to the prepubertal (HbA1c 8.22 +/- 1.25% vs. 7.81 +/- 0.87%; p < 0.01). In addition, we found better metabolic control in patients with duration of diabetes below 2 years in children and adolescents (HbA1c prepubertal < 2 years: 7.45 +/- 0.67% vs. > 2 years: 8.05 +/- 0.93%, p < 0.05; pubertal < 2 years: 7.62 +/- 0.75% vs. > 2 years: 8.31 +/- 1.29%, p < 0.005). Importantly, sex and insulin regimen did not significantly influence glycaemic control. CONCLUSION/INTERPRETATION The current level of metabolic control in our children and adolescents with diabetes mellitus type I is comparable to the glycaemic control of the intensively treated adolescent group of the DCCT-study, in whom decreased risk of long-term diabetic complications was found. In contrast, our patients were intensively treated in terms of frequent contacts with the diabetes team, but were not necessarily on an intensified insulin regimen. The impact of biopsychosocial support from multidisciplinary diabetes team on good metabolic control in children and adolescents with type I diabetes mellitus and their families seems to be very important.

Low single dose gabapentin does not affect prefrontal and occipital gamma-aminobutyric acid concentrations

The γ-aminobutyric acid (GABA) system has been proposed as a target for novel antidepressant and anxiolytic treatments. Emerging evidence suggests that gabapentin (GBP), an anticonvulsant drug that significantly increases brain GABA levels, is effective in the treatment of anxiety disorders. The current study was designed to measure prefrontal and occipital GABA levels in medication-free healthy subjects after taking 0 mg, 150 mg and 300 mg GBP. Subjects were scanned on a 3T scanner using a transmit-receive head coil that provided a relatively homogenous radiofrequency field to obtain spectroscopy measurement in the medial prefrontal (MPFC) and occipital cortex (OCC). There was no dose-dependent effect of GBP on GABA levels in the OCC or MPFC. There was also no effect on Glx, choline or N-acetyl-aspartate concentrations. The previously reported finding of increased GABA levels after GBP treatment is not evident for healthy subjects at the dose of 150 and 300 mg. As a result, if subjects are scanned on a 3T scanner, low dose GPB is not useful as an experimental challenge agent on the GABA system.