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1.
Namensgebend für das Jo-1-Syndrom sind Autoantikörper gegen das Jo-1-Antigen, die bei diesem Krankheitsbild im Serum der betroffenen Patienten nachgewiesen werden. Der Name Jo-1 leitet sich von dem ersten Patienten (John P.) ab, bei dem diese Antikörper gefunden wurden. Dieser Patient litt an einer Polymyositis und fibrosierenden Alveolitis. Das Jo-1-Antigen ist identisch mit der Histidyl-Transfer-RNA-Synthetase im Zytosol. Das Jo-1-Syndrom gehört zu einer Familie von Autoimmunerkrankungen, die als Anti-Synthetase- Syndrome bezeichnet werden. Diese Syndrome haben gemeinsam, dass jeweils Autoantikörper gegen unterschiedliche Aminosäure-Transfer-RNASynthetasen nachweisbar sind. Klinisch handelt es sich beim Jo-1-Syndrom um eine Sonderform der Poly- bzw. Dermatomyositis von bisher ungeklärter Ätiologie. Neben einer Muskelbeteiligung kommt es charakteristischerweise zu einer interstitiellen Lungenbeteiligung, die auch prognostisch das Krankheitsbild bestimmt. Zusätzlich können klinisch eine Polyarthritis und weitere Symptome bestehen, die dem klinischen Bild anderer Kollagenosen ähneln. Ebenso wie die Polymyositis und Dermatomyositis kann sich das Jo-1-Syndrom in sog. Myositis-Overlap-Syndromen präsentieren. Zu dieser Diagnose führt ein Symptomenkomplex, der die klare Zuordnung zu einer einzelnen Erkrankung nicht möglich macht. Häufig werden in solchen Fällen U1-RNP-Antikörper nachgewiesen. Therapeutisch spricht das Jo-1-Syndrom auf die Gabe von Kortikosteroiden und—falls notwendig—Azathioprin, Methotrexat und Cyclophosphamid an. Eine Kurzbeschreibung von zwei klinischen Fällen stellt das Krankheitsbild anschaulich dar.  相似文献   
2.
Waldenstrom's macroglobulinemia (WM) is an uncommon low-grade lymphoma. Cognitive impairment due to central nervous system infiltration by lymphoplasmocytoid cells (Bing-Neel syndrome) has been rarely reported. We describe a 54-year-old man who was referred to a memory disorder clinic with a 9-month history of clinically obvious nonfluent aphasia and WM. He underwent extensive neuropsychological testing, clinical examination and structural and functional brain imaging. The diagnosis of the diffuse form of the Bing-Neel syndrome was supported by abnormal lymphoid cells found in the cerebrospinal fluid. Structural and functional brain imaging revealed impairment of brain areas due to white matter changes and subsequent functional deficits mimicking the neuropsychological syndrome encountered in progressive nonfluent aphasia. The diffuse form of Bing-Neel syndrome and neurological deficits are assumed to be the result of leptomeningeal infiltration by malignant cells and/or neoplastic vascular obstruction.  相似文献   
3.
Depressive symptoms are common in patients with neurodegenerative disorders. Imaging studies suggest that a disruption of frontal-subcortical pathways may underlie depression associated with basal ganglia disease. This pilot study tested the hypothesis that frontal dysfunction contributes to depression associated with multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). Depressed patients with MSA (n = 11), PSP (n = 9), and age-matched controls (n = 25) underwent measures of cerebral glucose metabolism applying positron emission tomography with (18)F-fluorodeoxyglucose. Regional metabolism in the patient groups was compared to the normal subjects using the voxel-based statistical parametric mapping. Depressive symptom severity (Hamilton Depression Rating) and degree of locomotor disability (Hoehn & Yahr) were assessed in the patient groups. The association between prefrontal metabolism and the occurrence of depressive symptoms and the degree of locomotor disability was investigated. When compared to controls, MSA patients revealed significant metabolic decreases in bilateral frontal, parietal, and cerebellar cortex and in the left putamen. In PSP patients, significant hypometabolism was demonstrated in bilateral frontal cortex, right thalamus, and midbrain. Depression severity but not the patients' functional condition was significantly associated with dorsolateral prefrontal glucose metabolism in both patient groups. The findings of this pilot study support the hypothesis that depressive symptoms in MSA and PSP are associated with prefrontal dysfunction.  相似文献   
4.
A novel approach that uses the concepts of parallel imaging to grid data sampled along a non-Cartesian trajectory using GRAPPA operator gridding (GROG) is described. GROG shifts any acquired data point to its nearest Cartesian location, thereby converting non-Cartesian to Cartesian data. Unlike other parallel imaging methods, GROG synthesizes the net weight for a shift in any direction from a single basis set of weights along the logical k-space directions. Given the vastly reduced size of the basis set, GROG calibration and reconstruction requires fewer operations and less calibration data than other parallel imaging methods for gridding. Instead of calculating and applying a density compensation function (DCF), GROG requires only local averaging, as the reconstructed points fall upon the Cartesian grid. Simulations are performed to demonstrate that the root mean square error (RMSE) values of images gridded with GROG are similar to those for images gridded using the gold-standard convolution gridding. Finally, GROG is compared to the convolution gridding technique using data sampled along radial, spiral, rosette, and BLADE (a.k.a. periodically rotated overlapping parallel lines with enhanced reconstruction [PROPELLER]) trajectories.  相似文献   
5.
Deep brain stimulation of the subthalamic nucleus (STN-DBS) is an established therapy for Parkinson's disease (PD). A manic episode with psychotic symptoms induced by STN-DBS occurred in a previously psychiatrically healthy patient, focusing on the role of STN-DBS in influencing not only motor but also emotional behaviour.  相似文献   
6.
The aim of the present study was to explore cell biological characteristics of normal breast, benign proliferative breast diseases and noninvasive breast malignancies based on the recently published adult progenitor cell concept from our group. Here, we investigated the proliferative activity of CK5/14(+), CK8/18/19(+) and alpha-smooth muscle actin(+) cellular phenotypes encountered in normal mammary gland, in a series of usual ductal hyperplasias and early malignant breast diseases, such as atypical ductal and lobular hyperplasias, as well as ductal and lobular in situ carcinomas. Immunohistochemical double labeling was performed on frozen sections from diagnostic breast biopsies by using antibodies to basal cytokeratins (CK5/14), glandular cytokeratins (CK8/18/19), smooth muscle actin and the Ki-67 antigen (MIB1). Normal breast tissues and usual ductal hyperplasias were characterized by a heterogeneous cellular composition of the growth fraction. The proliferative cell compartment consisted of CK8/18/19(+) glandular and, in a variable proportion, CK5/14(+) progenitor phenotypes. In contrast, noninvasive breast malignancies were composed of a monotonous proliferation of CK 8/18/19(+) neoplastic glandular cells. These findings indicate a significant role of progenitor cells in the development of benign proliferative breast diseases and lend support to the view that malignant transformation in the human breast usually occurs in a cell committed to the glandular lineage. Our results provide cell kinetic support to the functional progenitor cell hypothesis, and we propose this concept as an operative model for understanding benign proliferative and malignant breast diseases.  相似文献   
7.
Specific receptors for vitamin D have been identified in human muscle tissue. Cross-sectional studies show that elderly persons with higher vitamin D serum levels have increased muscle strength and a lower number of falls. We hypothesized that vitamin D and calcium supplementation would improve musculoskeletal function and decrease falls. In a double-blind randomized controlled trial, we studied 122 elderly women (mean age, 85.3 years; range, 63-99 years) in long-stay geriatric care. Participants received 1200 mg calcium plus 800 IU cholecalciferol (Cal+D-group; n = 62) or 1200 mg calcium (Cal-group; n = 60) per day over a 12-week treatment period. The number of falls per person (0, 1, 2-5, 6-7, >7 falls) was compared between the treatment groups. In an intention to treat analysis, a Poisson regression model was used to compare falls after controlling for age, number of falls in a 6-week pretreatment period, and baseline 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D serum concentrations. Among fallers in the treatment period, crude excessive fall rate (treatment - pretreatment falls) was compared between treatment groups. Change in musculoskeletal function (summed score of knee flexor and extensor strength, grip strength, and the timed up&go test) was measured as a secondary outcome. Among subjects in the Cal+D-group, there were significant increases in median serum 25-hydroxyvitamin D (+71%) and 1,25-dihydroxyvitamin D (+8%). Before treatment, mean observed number of falls per person per week was 0.059 in the Cal+D-group and 0.056 in the Cal-group. In the 12-week treatment period, mean number of falls per person per week was 0.034 in the Cal+D-group and 0.076 in the Cal-group. After adjustment, Cal+D-treatment accounted for a 49% reduction of falls (95% CI, 14-71%; p < 0.01) based on the fall categories stated above. Among fallers of the treatment period, the crude average number of excessive falls was significantly higher in the Cal-group (p = 0.045). Musculoskeletal function improved significantly in the Cal+D-group (p = 0.0094). A single intervention with vitamin D plus calcium over a 3-month period reduced the risk of falling by 49% compared with calcium alone. Over this short-term intervention, recurrent fallers seem to benefit most by the treatment. The impact of vitamin D on falls might be explained by the observed improvement in musculoskeletal function.  相似文献   
8.
Studies using magnetic resonance spectroscopy in human volunteers to evaluate their livers in vivo and to analyze their blood in vitro suggest that there are measurable amounts of silicon compounds in the blood of some women with implants and that there is migration of silicone to other organs such as the liver.  相似文献   
9.
This laboratory study tested new methods to analyze hemostasis alterations in septic patients. Samples of ethylenediamine tetraacetic acid (EDTA) plasma and citrated plasma were collected from 62 patients with clinical diagnosis of sepsis. Additionally, a subset of EDTA-plasma samples from each patient was stabilized 1 + 1 with 2.5 mol/l arginine, pH 8.6, to conserve the real hemostasis activation state. EDTA-arginine plasma, EDTA plasma and citrated plasma samples were tested in duplicate. The patients at admission to the intensive care unit had 36 +/- 26 (normal, 0.8 +/- 0.2) ng/ml global endotoxin reactivity, 188 +/- 66% (normal, 100 +/- 20%) fibrinogen function, 179 +/- 66% (normal, 100 +/- 20%) fibrinogen antigen, 4.0 +/- 3.6 (normal, 0.049 +/- 0.025) microg/ml D-dimer, 313 +/- 307% (normal, 100 +/- 30%) plasmin-antiplasmin complex, 8.7 +/- 11.4 (normal, 1.1 +/- 0.7) U/ml plasminogen activator inhibitor-1, 12.1 +/- 10.5 (normal, 1.3 +/- 0.4) ng/ml thrombin-antithrombin III complex, 173 +/- 62% (normal, 100 +/- 20%) thrombin, 568 +/- 225 (normal, 140 +/- 42) pg/ml tissue factor, and 2.56 +/- 2.48 (normal, 0.19 +/- 0.04) microg/ml soluble intercellular adhesion molecule-1. Endotoxin (lipopolysaccharide and/or beta-glucan) reactivity (EDTA plasma), fibrinogen function + antigen + ratio and plasminogen activator inhibitor-1 (citrated plasma), and D-dimer, soluble intercellular adhesion molecule-1, thrombin activity (EDTA-arginine-stabilized plasma) presented large aberrations in septic patients when compared with normal values and may therefore be particularly interesting as markers of hemostasis alteration. Whether the observed alterations are of clinical significance has to be determined in well defined patient groups.  相似文献   
10.
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