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931.
Zweckberger K Hackenberg K Jung CS Hertle DN Kiening KL Unterberg AW Sakowitz OW 《Neurological research》2011,33(8):875-880
After traumatic brain injury, a cascade of metabolic changes promotes the development of secondary brain damage. In this study, we examined metabolic changes in rats in the acute stage after trauma. Furthermore, we investigated the effect of a very early decompression craniotomy on intracranial pressure (ICP) and on metabolic parameters. For this study, a moderate controlled cortical impact injury (CCII) on rats was performed. The observation time was 180 minutes after trauma. ICP was measured continuously and microdialysate samples were collected every 30 minutes from the peri-contusional region. As representative metabolic parameters, glutamate, lactate, lactate/pyruvate ratio (L/P ratio), and glucose concentrations were measured. Compared to sham-operated animals, a significant, sustained decrease in glucose concentration and increase in L/P ratio occurred immediately after CCII. Additionally, delayed increase in lactate and glutamate concentrations occurred 60 minutes after trauma. After this initial peak, glutamate concentrations declined continuously via the observation time and reached levels comparable to sham-operated animals. In our model, thus we could detect a very early deterioration of glucose utilization and energy supply after trauma that recovered, due to the moderate intensity of the trauma, within 60 minutes without leading to ischemia in the peri-contusional region. Following decompression craniotomy, the increase of intracranial pressure could be reduced significantly. Any significant beneficial effects on metabolic changes, however, could not be proven in this very early stage after moderate CCII. 相似文献
932.
The daily co-occurrence of change in sleep characteristics and psychopathology was examined in six individuals with schizophrenia and seven healthy controls using a prospective assessment of rest-activity patterns conducted in the person's home for up to 28 days. The results provide preliminary evidence that a change in sleep-wake timing is followed by a change in symptom severity. 相似文献
933.
Ille R Holl AK Kapfhammer HP Reisinger K Schäfer A Schienle A 《Psychiatry research》2011,188(3):377-382
Findings on affective processing deficits in Huntington's disease (HD) have been inconsistent. It is still not clear whether HD patients are afflicted by specific deficits in emotion recognition and experience. We tested 28 symptomatic HD patients and presented them with pictures depicting facial expressions of emotions (Karolinska-Set) and with affective scenes (International Affective Picture System; IAPS). The faces were judged according to the displayed intensity of six basic emotions, whereas the scenes received intensity ratings for the elicited emotions in the viewer. Patients' responses were compared with those of 28 healthy controls. HD patients gave lower intensity ratings for facial expressions of anger, disgust and surprise than controls. Patients' recognition deficits were associated with reduced functional capacity, such as problems with social interactions. Moreover, their classification accuracy was reduced for angry, disgusted, sad and surprised faces. When judging affective scenes for the elicitation of happiness, disgust and fear, HD patients had a tendency to estimate them as more intense than controls. This finding points to a differential impairment in emotion recognition and emotion experience in HD. We found no significant correlations between emotion experience/recognition ratings and CAG repeats, symptom duration and UHDRS Motor Assessment in the patient group. 相似文献
934.
Body dysmorphic disorder (BDD) is a distressing or impairing preoccupation with an imagined or slight defect in appearance. Only a few studies have examined BDD prevalence in psychiatric settings. Prevalence rates vary widely and most studies have been conducted in outpatient samples. In the current study, we examined 155 adult psychiatric inpatients. Diagnostic criteria of BDD were assessed with the BDD module of the Structured Clinical Interview for DSM-IV. The prevalence of lifetime BDD was 2.6% (95% CI = 0.1-5.1%). Currently 1.9% of the patients suffered from BDD (95% CI = 0.0-4.0%). None of these patients were diagnosed with BDD on admission or during hospitalization. The BDD rates found in this study are considerably lower than lifetime and current prevalence rates reported by two other studies conducted in adult psychiatric inpatient settings (
[Grant et al., 2001] and [Conroy et al., 2008]). The differences may be explained by divergent sample compositions and variation in diagnostic measures. The findings of the current study underline the need for further studies examining BDD prevalence in psychiatric settings and suggest using a combination of screening questionnaire and follow-up interview to diagnose BDD. 相似文献
935.
In prion diseases, neuroimmunological responses include activation of microglia, astrocytosis and release of pro- and anti-inflammatory cytokines, which might substantially contribute to the neurodegenerative process. In this study we investigated neopterin and beta(β)2-microglobulin, as markers of cellular immune activation, in the cerebrospinal fluid (CSF) of patients with Creutzfeldt-Jakob disease (CJD) and of patients with other neurological and non-neurological diseases. CSF samples from CJD patients were collected in the framework of the German CJD Surveillance study. Concentrations of neopterin and β2-microglobulin were determined in CSF using ELISA. We could not obtain significant changes in CSF levels of neopterin and β2-microglobulin in CJD patients when compared to other neurological and non-neurological controls. In a subanalysis of CJD patients only, we could find significant elevated neopterin levels in patients with MV genotype, potentially reflecting a distinct disease pathology. Since autoimmune inflammatory disorders are important differential diagnoses in CJD, additional biomarker might be helpful in clinical setting. 相似文献
936.
Ulrike Hoffmann Jeong Hyun Lee Tao Qin Katharina Eikermann-Haerter Cenk Ayata 《Journal of cerebral blood flow and metabolism》2011,31(7):1578-1582
Spreading depression (SD) is an intense depolarization wave implicated in brain injury. In focal ischemia, recurrent peri-infarct depolarization (PID) waves akin to SD worsen the ischemic injury by exacerbating the blood flow-metabolism mismatch. We recently showed that gabapentin suppresses SD. We, therefore, tested gabapentin on PIDs and stroke outcome. Gabapentin pretreatment (200 mg/kg, intravenously) reduced the infarct volume by 23% after transient focal ischemia in mice. However, the frequency and duration of PIDs were not suppressed when recorded for 2 hours during ischemia, suggesting that gabapentin reduces infarct volume independent of PID suppression. 相似文献
937.
938.
The ease with which humans are able to perform symmetric movements of both hands has traditionally been attributed to the preference of the motor system to activate homologous muscles. Recently, we have shown in right-handers, however, that bimanual index finger adduction and abduction movements in incongruous hand orientations (one palm down/other up) preferentially engaged parietal perception-associated brain areas. Here, we used functional magnetic resonance imaging to investigate the influence of hand orientation in left-handers on cerebral activation during bimanual index finger movements. Performance in incongruous orientation of either hand yielded activations involving right and left motor cortex, supplementary motor area in right superior frontal gyrus (SMA and pre-SMA), bilateral premotor cortex, prefrontal cortex, bilateral somatosensory cortex and anterior parietal cortex along the intraparietal sulcus. In addition, the occipito-temporal cortex corresponding to human area MT (hMT) in either hemisphere was activated in relation to bimanual index finger movements in the incongruous hand orientation as compared with the same movements in the congruous hand orientation or with simply viewing the pacing stimuli. Comparison with the same movement condition in right-handed subjects from a former study support these hMT activations exclusively for left-handed subjects. These results suggest that left-handers use visual motion imagery in guiding incongruous bimanual finger movements. 相似文献
939.
Luxembourg B Schneider K Sittinger K Toennes SW Seifried E Lindhoff-Last E Oldenburg J Geisen C 《Thrombosis and haemostasis》2011,105(1):169-180
Compared to warfarin, little is known about the effect of pharmacogenomics on the inter-individual variability of phenprocoumon therapy. In a retrospective cohort study, we investigated the impact of VKORC1 c.-1639G>A; CYP2C9*2 , CYP2C9*3 ; GGCX c.214+597G>A; CALU c.*4A>G; EPHX1 c.337T>C; F7 c.-402G>A, and F7 c.-401G>T on the initiation (n=54) and maintenance phases (n=91) of phenprocoumon therapy. We assessed the following outcome parameters: time to stable international normalised ratio (INR), time to first supra-therapeutic INR, time out of INR range, probability of over-anticoagulation, number of anticoagulation clinic visits. During the initiation phase, homozygotes for the VKORC1 c.-1639 A and G alleles achieved stable INRs later (p<0.001), spent more time at supra-therapeutic INRs (p<0.001), had increased risks of over-anticoagulation (odds ratio 19.83, p=0.003 and 4.45, p=0.045, respectively), and had higher frequencies of anticoagulation clinic visits (p<0.001) compared to GA carriers. CYP2C9*2, *3 carriers reached stable INRs faster (p=0.024) with fewer anticoagulation clinic visits (p=0.001) than wild-type carriers. EPHX1 c.337 C carrier spent significantly more time above range in the initiation phase (p=0.023). GGCX , CALU , and F7 gene variants did not affect outcome parameters of the initiation phase and none of the genotypes had an impact on maintenance phase parameters. Compared to the VKORC1 genotype, early INR values were less informative in the prediction of outcome parameters such as time to stable INR and time above the INR range. Our study is limited by the retrospective study design with no standardised protocol in a usual care setting. Therefore, our findings should be validated in a larger, controlled prospective study. 相似文献
940.