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Biomedical subjects

M Bartels

Publications and source records attributed to M Bartels.

At least 55 records · Page 3Linked to original sources
PubMed2000

Left prefrontal activation predicts therapeutic effects of repetitive transcranial magnetic stimulation (rTMS) in major depression.

There is evidence that repetitive transcranial magnetic stimulation (rTMS) applied to the prefrontal cortex has antidepressive properties. In the present study we evaluated the clinical status and the hemodynamic responses during mental work in the prefrontal cortex before therapeutic rTMS. Twelve patients diagnosed with major depression (DSM-IV) were randomized in a sham-controlled cross-over treatment protocol of 4 weeks' duration consisting of two periods of 5 days with rTMS separated by 9 days of no stimulation. rTMS (10 Hz) was applied to the left dorsolateral prefrontal cortex. Hemodynamic changes in the prefrontal cortex during mental work were evaluated by multi-site near-infrared spectroscopy (NIRS). Scores on the Hamilton Depression Rating Scale (HAMD) decreased significantly by -5.4 points after 5 days of active stimulation, whereas it did not change (+1.6 points) after sham stimulation. Absence of a task-related increase of total hemoglobin concentrations at the stimulation site (P<0.005), but not at other locations, before the first active rTMS significantly predicted the clinical response to active rTMS. Clinical benefits of rTMS are predicted by low local hemodynamic responses and support the idea of activation-dependent targeting of rTMS location.

Brain Mapping↗
PubMed2000

Video camera and light system for application in magnetic resonance scanners.

The direct observation and simultaneous recording of subject behavior, e.g. facial movements, during MR imaging is necessary for a variety of functional imaging studies involving phenomena such as emotions, humor, mood, etc. Such observation is also valuable for the monitoring of very ill or young patients. We describe a color video camera and light system which works within the functioning scanner. The camera acquires high resolution video sequences during conventional T(1)-weighted and functional T(2)*-weighted imaging. When fixed to the head coil artefacts during the MRI-acquisition were insignificant. The video allows observation of the face detailed enough to permit FACS scoring of facial expressions. We therefore propose that it can be applied for a wide variety of studies needing visual feedback of subject behavior.

Artifacts↗
PubMed2000

Towards a functional neuroanatomy of self processing: effects of faces and words.

We studied the neural correlates of self vs. non-self judgements using functional magnetic resonance imaging (fMRI). Individually tailored faces and personality trait words were used as stimuli in three experiments (exp.). In the first two experiments, brain activation was measured while subjects viewed morphed versions of either their own (self face exp.) or their partner's face (partner's face exp.), alternating in blocks with presentation of an unknown face. In the self face exp. right limbic areas (hippocampal formation, insula, anterior cingulate), the right middle temporal lobe, left inferior parietal and left prefrontal regions showed signal changes. In the partner's face exp., only the right insula was activated. In the third exp., subjects made decisions about psychological trait adjectives previously categorized as describing their own attributes. Activation was present in the precuneus, the left parietal lobe, left insula/inferior frontal gyrus and the left anterior cingulate. A reaction time advantage was present when subjects responded to self-relevant words. The main area with signal changes during self-reference processing, regardless of the type of stimulus, was the left fusiform gyrus. The self-relevant stimuli engaged to a differential extent long term and working memory, semantic and emotional processes. We suggest that regions activated by these stimuli are engaged in self-processing.

Adult↗
PubMed2000

Pancreatic metastasis of a pleuropulmonary blastoma in an adult.

Pleuropulmonary blastoma (PPB) is a rare dysontogenetic tumor that usually develops in the first decade of life and has been recognized as a distinct clinico-pathological entity different from the ordinary pulmonary blastoma of adulthood. Since the tumor grows aggressively and tends to metastasize early, physicians have to be aware of late onset of symptoms and uncommon manifestations. We report a case of PPB in a young adult and its recurrence in the pancreas after primary surgical treatment and adjuvant chemotherapy. Keeping in mind the moderate prognosis of PPB in children, accurate assessment and treatment of PPB require a team approach of oncology, radiology and surgery to establish new therapeutic guidelines in the future.

Adolescent↗
PubMed1999

[Need for approval of electroconvulsive therapy from the Guardian- ship Court within the context of guardianship (Section 1904 BGB)].

If patients who need electroconvulsive therapy are unable to consent, it is necessary to gain the guardian's permission to carry out the treatment. It remains unclear if, due to possible side effects, it is necessary to gain an additional approval from the Guardianship Court according to Section 1904 of German Civil Code (BGB). The high court of Hamburg (Landgericht Hamburg) decided that legal permission is necessary as a result of the risk of persisting retrograde amnesia and the ensuing danger of permanent damage to the patient's health. This paper points out however, that electroconvulsive therapy, even considering the contraindications, is a safe and effective treatment for depression and schizophrenic psychoses. Application of unilateral short-pulse stimulation reduces the frequency and intensity of cognitive side effects. In particular, retrograde amnesia is very rare with regard to frequency and intensity and is negligible when compared with the dangers of the illness itself. Therefore, it is not necessary to apply for approval from the Guardianship Court.

Amnesia↗
PubMed1999

Psychiatrists meet on the web: the chance for a virtual congress. Results and experiences from the First International Internet Congress on Psychiatry 1997.

From December 1-31, 1997, the Department of Psychiatry and Psychotherapy in co-operation with the Department of Information Technology, University of Tübingen, Germany, organised the first virtual congress on psychiatry in the Internet. The congress was aimed at facilitating exchange of results of psychiatric studies and ideas and at stimulating discussion among interested colleagues. Almost 100 participants from 17 countries on four continents took part in this event. Sixteen contributions were presented and discussed. The problems and opportunities of this medium in the organisation and running of congresses are presented and discussed. The experience gained in this congress suggests that the Internet will find increasing use as a medium for medical congresses within the next few years.

Germany↗
PubMed1998

[Early morphological changes in Crohn disease as further evidence for conservative resection indications].

Clinical studies revealed that the size of the margin of resection and the microscopic findings at the edge of the specimen did not influence the rate of recurrence. Regarding early lesions of Crohn's disease, the aim of the present study was to identify morphological alterations which are able to explain the clinical findings and are in accordance with the operative procedure. In the present study the resection margins of 29 patients with Crohn's disease were investigated using the scanning electron microscope. Seventy-three percent of patients with histopathologically unaffected resection margins in the small bowel and 71% in the large bowel showed early lesions. These consisted of mucosal architectural alterations, epithelial bridge formation and goblet cell hyperplasia and hypertrophy. Curative resection is not possible, independent of the resection margins. The morphological findings underline the correctness of the usual operative procedure, namely limited resections in Crohn's disease.

Crohn Disease↗
PubMed1998

Antibrain antibodies in mental disorder: no evidence for antibodies against synaptic membranes.

Antibody reactivity in serum to synaptic membranes from human was investigated in major depressive disorder (N = 20), paranoid schizophrenia (N = 20), schizoaffective psychosis (N = 20), and in controls (N = 20) using Western and Immunoblots and ELISA technique. None of the patients showed a significant immune response to synaptic membranes. There was a base-line activity in both controls and patients with antibodies directed to a double band of proteins at 66kD. These antibodies may represent natural autoantibodies. The authors conclude from this and other studies that there is at present no proof of antibrain antibodies in mental disorder.

Adult↗
PubMed1998

Coagulatory response after femoral instrumentation after severe trauma in sheep.

OBJECTIVE: Pulmonary complications after intramedullary femoral nailing have been attributed to bone marrow fat embolization and a variety of cascade effects. We investigated whether the coagulatory response after intramedullary femoral nailing in merino sheep is altered after severe trauma. METHODS: Adult merino sheep were submitted to hemorrhagic shock (2 hours, 50 mm Hg) and unilateral lung contusion. After recovery (day 3 of the study), reamed femoral intramedullary nailing (RFN), unreamed femoral intramedullary nailing (UFN), or plate osteosynthesis of the femur (P) was performed. Pulmonary artery pressure, central venous levels of factor V, protein C, antithrombin III, and fibrinogen, were determined. At 1 and 3 days before and after femur instrumentation, pulmonary capillary permeability was assessed on the basis of the comparative albumin content in bronchoalveolar lavage fluid. RESULTS: Group RFN, n=8; group UFN, n=7; group P, n=6. A significant (p < 0.05) postoperative increase in the relative albumin content in terms of the BAL/plasma albumin ratio was measured in group RFN (day 3 preoperatively: 0.38+/-0.05 day 3 postoperatively: 0.53+/-0.06, p < 0.05 (RFN vs. P), which contrasted with group UFN (day 3 preoperatively: 0.44+/-0.09, day 3 postoperatively: 0.46+/-0.09, no significant difference). This evidence of increased pulmonary permeability occurred in association with evidence of increased activation of coagulation factors (data presented as percentage of day 3 preoperative baseline values). The data for fibrinogen (15 min postoperatively) is as follows: group RFN, 74+/-9% (p < 0.05 vs. P); group UFN, 83+/-8% (not significant); group P, 98+/-6%. The data for antithrombin III (15 min. postoperatively) is as follows: group RFN, 72+/-6% (p < 0.05 vs. P); group UFN, 79+/-8% (not significant); group P, 92+/-8% (not significant). CONCLUSION: After severe trauma, an increase of pulmonary permeability after reamed femoral nailing was associated with increased consumption of coagulation factors. After unreamed nailing, a similar trend was apparent, but this was not found to be statistically significant. These data provide support for the theory that after severe trauma, unreamed femoral nailing reduces but does not abolish pulmonary sequelae when compared with reamed femoral nailing.

Adolescent↗
PubMed1998

Transcultural study of schizophrenic delusions. Tokyo versus Vienna and Tübingen (Germany).

Schizophrenic delusions of 324 inpatients in Tokyo, 101 in Vienna, and 150 in Tübingen (Germany) were compared according to the same classifications. Among the three areas, about 80% of the patients had equally 'negative' delusions (injury and/or belittlement), and about one-fourth had 'positive' delusions of grandeur. Transcultural influences were found in the detailed contents of the 'negative' delusions; specific and direct themes of persecutory delusion, i.e., delusions of poisoning, and religious themes of guilt/sin were conspicuous in Europe, while amorphous delusions of reference such as 'being slandered' were predominant in Japan. The latter may derive from the group-oriented self in Japanese 'shame culture'.

Adult↗
PubMed1998

[Diagnostic and therapeutic strategies in hepatocellular adenoma].

While liver hemangioma and focal nodular hyperplasia are not considered an indication for surgery in asymptomatic patients resection has been recommended for hepatocellular adenoma because of the risk of rupture and malignant transformation. Problems arise from differential diagnosis and the appropriate surgical radicality including the indication for liver transplantation. This retrospective analysis deals with 58 patients who underwent surgery for hepatocellular adenoma: resection of different extension: n = 54, liver transplantation n = 4. In 39.6% of the patients the tumor was an incidental finding. In 62.0% of the character of the lesion was unclear prior to surgery. Tumor rupture and bleeding occurred in 17.2%, malignant transformation in 6.9%. Surgical morbidity was 27.6%, mortality 5.2% with the transplant patients alive for 1.5, 7, 9 and 10 years. Two and five years after resection 2 patients developed hepatocellular carcinoma in the liver remnant. The results confirm the indication for surgery in hepatocellular adenoma. Diagnostic approach for solid liver tumors without serum increase of tumor markers should rule out FNH and hemangioma. In all other patients surgery should be considered whenever possible with the radicality of malignant disease. Liver transplantation can be discussed even in asymptomatic patients with multiple adenoma.

Adenoma, Liver Cell↗
PubMed1997

Therapeutic options in Charles Bonnet syndrome.

The term 'Charles Bonnet syndrome' refers to visual pseudohallucinations occurring especially in elderly people with reduced visual acuity. Despite numerous case reports, few successful methods of treatment have been described. Therapies with classical neuroleptics, antidepressants or benzodiazepines have generally been found to be unpromising. Only with carbamazepine treatment has improvement been observed in a few cases. In the three cases reported here, we successfully treated the condition with the atypical neuroleptic melperone.

Aged↗
PubMed1997

Antioxidative vitamins in prevention of ischemia/reperfusion injury.

Involvement of oxygen free radicals in ischemia-/reperfusion injury is based on measurement of increased products of lipid peroxidation after organ ischemia and restoration of blood flow during surgical operations and reperfusion of organ transplants. In cardiology inverse epidemiological correlations between plasma vitamin E levels and mortality due to ischemic heart disease, as well as beneficial effects of vitamin E on experimentally induced oxidative damage to the heart support the hypothesis, that vitamin E might have a protective role against myocardial ischemia-/reperfusion injury. In abdominal surgery efficiency of free radical scavengers has been intensively studied on animal models of hepatic ischemia and reperfusion. Examination of free radical scavengers and adenosine metabolites in liver tissue during hepatic ischemia revealed that vitamin E and glutathione levels as well as hepatic adenosine triphosphate levels are decreased during hepatic ischemia and reperfusion. The beneficial effects of alpha-tocopherol on hepatic viability and survival rate after ischemia and reperfusion demonstrated in these studies will be of great importance concerning further studies in organ preservation. In clinical kidney transplantation prevention of lipid peroxidation and improvement in kidney viability and function was demonstrated after infusion of a multivitamin cocktail in a prospective randomised study.

Antioxidants↗
PubMed1996

Confirmation of reduced temporal limbic structure volume on magnetic resonance imaging in male patients with schizophrenia.

A structural deficit in the temporal lobes has been implicated in the pathogenesis of schizophrenia. A prospective magnetic resonance imaging (MRI) study was carried out in 20 young male patients with schizophrenia and 20 age-matched healthy male volunteers. Volumetric measurements were performed in all slices with temporal lobe cross-sections from the temporal pole to the tip of the Sylvian fissure. Volumetric assessment included the temporal lobe as a whole, hippocampal formation and amygdala complex, temporal horn and cella media of the lateral ventricle, the third ventricle, and hemispheric volume in all slices that showed temporolimbic structures. Brain structural deficit in the patients was most conspicuous in the posterior portion of the hippocampal formation. Significant effects of diagnosis were also found for the total temporal lobe and the third ventricle. Multiple regression analysis revealed posterior hippocampal volume to be significantly determined by diagnosis, but not by age or by temporal lobe or hemispheric volume. Significant correlations of morphologic and clinical parameters were restricted to negative correlations of temporal lobe volume with the global rating and sum score of the Scale for the Assessment of Negative Symptoms. The study confirms subtle temporolimbic deficit reported in previous MRI studies in patients with schizophrenia.

Adult↗
PubMed1996

Abnormal topography of EEG microstates in Gilles de la Tourette syndrome.

Quantitative analysis of scalp EEGs was performed on 13 patients with Gilles de la Tourette syndrome (GTS) and 25 matched controls. The analysis method was adaptive segmentation, which describes the topography and sequence of brain electric fields in continuous EEG. The GTS patients showed an abnormal increase in fields with a right-frontal/left-posterior configuration. The GTS patient's EEGs did not differ from normal controls in the average duration of the brain electric microstates, field stability and EEG carrier frequency. To find out whether the abnormal activity is similar to movement-related activity a simple and a complex motor task were performed. Both tasks led to distinct changes of brain electric activity, but not to an increase in right-frontal-/left-posterior-oriented patterns. Motor-related activity was contrasted with two auditory tasks. We conclude that GTS patient's EEG show abnormal topographic patterns of brain electric activity. Unlike other psychiatric disorders, the temporal descriptors of the EEG aspects are unaffected. The abnormal EEG patterns in GTS patients are not similar to those elicited by simple or complex movements; thus, the presence of abnormally facilitated, near-threshold motor activity in GTS patients seems not a likely explanation.

Adult↗
PubMed1996

Squamous cell carcinoma of the liver originating from a solitary non-parasitic cyst case report and review of the literature.

Squamous cell carcinoma of the liver arising from a non-parasitic cyst is a rare entity of a primary liver tumor with an unfavourable prognosis. We report a case of a patient with a cyst in the right lobe leading to upper abdominal symptoms and respiratory discomfort. Malignancy was not suspected from the clinical findings or repeated cytological examination of the cyst fluid. However, the blood stained brown color of the cyst fluid was unusual. Cyst recurrence after six attempts of conservative treatment with sonography guided drainage over a period for more than one year led to laparotomy with cyst unroofing. Because frozen section from the cyst wall revealed the unexpected finding of squamous cell carcinoma right hemihepatectomy was performed during the same operation. The patient is alive more than four years after surgery without cyst or tumor recurrence. The difficulties in establishing diagnosis are confirmed by the review of other reports. In the diagnosis and treatment of symptomatic non-parasitic liver cysts possible malignancy has to be considered. In case of proven carcinoma radical surgery with partial hepatectomy should be performed.

Aged↗
PubMed1996

Experience with color-coded duplex sonography after combined kidney/pancreas transplantation--preliminary results.

The value of color-coded duplex sonography in the assessment of combined kidney and pancreatic transplantations (KTX/PTX) was studied in 9 patients. In normal graft function the median resistive index (RI) was 0.69 (range 0.60-0.80) for the kidney and 0.61 (range 0.55-0.70) for the pancreas. Ten episodes of graft dysfunction (kidney n = 4; pancreas n = 6) were observed. During renal rejection and hemolytic uremic syndrome the RI was above 0.80. In pancreatic rejection the RI exceeded 0.80 while all other causes of pancreatic dysfunction were not associated with changes in the RI. Color-coded duplex sonography may prove to be a reliable noninvasive diagnostic method in the evaluation of the posttransplant course after combined KTX/PTX, in particular in the diagnosis of pancreatic rejection.

Diabetes Mellitus, Type 1↗