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51.
Summary Clinical and pathological features of an adult variant of adreno-leukodystrophy (ALD) are presented. A male with clinical and laboratory signs of Addison's disease (AD) developed at age 22 a slowly progressing paraplegia with slight sensory deficits in both legs and bladder and sphincter dysfunctions; he died at age 24 in an AD crisis. Autopsy revealed hyperplasia of lymphatic tissues, lymphocytic infiltrates in various organs including the CNS and adrenocortical atrophy with prominence of large ballooned, sometimes bizarre and occasionally striated cortical cells. CNS lesions consisted in incomplete demyelination of long tracts of brain stem and spinal cord with accentuation in the pyramical tracts; in these areas, perivascular cuffs of epitheloid histiocytic cells contained a strongly PAS-positive non-sudanophilic material. Electron microscopy demonstrated massive storage of leaflet structures in perivascular histiocytes identical to the lamellar profiles previously described as specific for ALD. Some leaflets were found in close contact with compact lamellar arrays and with an electron-dense fingerprint material within astrocytes.In our case, the spastic paraplegia-AD syndrome which has been described previously in several clinical observations could be neuropathologically classified as an adult variant of ALD. Several differences to classical ALD occurring in young boys are stressed: the predominance of the endocrine disorder probably accounting for some of the perivascular lymphocytic infiltrates within the CNS; the absence of both clinical and pathological signs of diffuse cerebral involvement and the peculiar topistic pattern of CNS lesions and the very slow evolution of neurological signs paralleled by the absence of active sudanophilic demyelinating lesions. The possible mechanism of demyelination and the nature of the suggested metabolic defect in ALD are discussed. The ultrastructurally prominent leaflet structures may originate from myelin remnants, thus relating ALD to pathological storage of a myelin degradation product.
Zusammenfassung Klinische und pathologische Befunde einer adulten Form der Adrenoleukodystrophie (ALD) werden dargestellt. Ein Patient mit klinischem Bild und Laboratoriumsbefunden der Addison-Krankheit (AD) entwickelte im Alter von 22 Jahren eine sehr langsam zunehmende Paraspastik mit geringer Hypaesthesie in beiden Beinen und Blasenund Mastdarmstörungen; er verstarb im Alter von 24 Jahren in einer AD-Krise. Bei der Autopsie fanden sich eine Hyperplasie des lymphatischen Apparats und lymphocytäre Infiltrate in verschiedenen Organen einschließlich des ZNS; beide Nebennieren waren atroph mit Hervortreten großer ballonierter, etwas bizarrer Rindenzellen mit gelegentlicher cytoplasmatischer Streifung. Im ZNS fanden sich pseudosystematische inkomplette Entmarkungen der langen Bahnen in Hirnstamm und Rückenmark mit Betonung der Pyramidenbahn, charakterisiert durch perivasale Manschetten epitheloider histiocytärer Zellen, die ein stark PAS-positives sudannegatives Material enthielten. Elektronenoptisch wurde eine massive Speicherung eines lamellären Materials in perivasalen Histiocyten nachgewiesen, welches mit den als spezifisch für die ALD angesehenen Einschlüssen übereinstimmte. Einige derartige Strukturen zeigten einen engen Zusammenhang mit kompakten Lamellenaggregaten und mit einem elektronendichten fingerprint-Material innerhalb von Astrocyten.In diesem Fall konnte das Paraplegie-AD-Syndrom, welches mehrfach bereits klinisch beschrieben worden war, aufgrund neuropathologischer Befunde als adulte Variante der ALD klassifiziert werden. Die Unterschiede dieser Form zur klassischen ALD, welche üblicherweise Knaben betrifft, werden hervorgehoben: das Überwiegen der endokrinen Symptomatik, was das Auftreten perivasaler Lymphocytensäume im ZNS zum Teil bedingen dürfte; das Fehlen klinischer und pathologischer Hinweise auf diffuse Beteiligung des Großhirns und die spezielle Topik der ZNS-Läsionen und die geringe Progredienz der neurologischen Symptomatik, welche im Einklang mit dem Fehlen florider sudanophiler Entmarkungsvorgänge steht. Der Mechanismus der Entmarkung und die Art der vermuteten metabolischen Störung bei der ALD werden diskutiert. Die elektronenoptisch charakteristischen lamellären Strukturen könnten aus dem Myelinabbau stammen, und damit könnte bei der ALD eine pathologische Speicherung eines Myelinabbauprodukts vorliegen.
  相似文献   
52.
Summary The effect of antipsychotic drugs was tested on responses to micro-electrophoretically applied dopamine, acetylcholine and 5-hydroxy-tryptamine in identified neurons of the marine gastropod Aplysia californica. Fluphenazine was able to depress the response to DA in concentration of 10M, with 100M DA-responses of many neurons were blocked completely. Thioridazine (10 and 100M) and haloperidol (50M) were also effective in depressing DA-responses, while the non-antipsychotic phenothiazines mepazine (10 and 100M) and promethazine (100M) had only a slight action on DA-receptors. ACh-and 5-HT-responses were slightly affected only by high concentrations after long lasting perfusion. The investigated drugs had no persistent or only an insignificant effect on resting membrane potential and amplitude of action potentials of the neurons. With haloperidol depolarizing afterpotentials leading to double discharges were observed in some neurons. In a few instances spontaneous EPSPs disappeared with the DA-response under the influence of anti-psychotic drugs.The results render a direct neurophysiological evidence for the blockade of DA-receptors by antipsychotic drugs in correspondence to their clinical efficacy and agree with data from clinical observations and obtained in neurochemical, behavioral and indirect neurophysiological experiments.Supported by the österreichischen Fonds zur Förderung der wissenschaftlichen Forschung. —A preliminary report of a part of the results was published in Experientia30, 1318–1320 (1974).  相似文献   
53.
BACKGROUND AND PURPOSE: Central benzodiazepine receptor ligands, such as [(11)C]flumazenil (FMZ), are markers of neuronal integrity and therefore might be useful in the differentiation of functionally and morphologically damaged tissue early in ischemic stroke. We sought to assess the value of a benzodiazepine receptor ligand for the early identification of irreversible ischemic damage to cortical areas that cannot benefit from reperfusion. METHODS: Eleven patients (7 male, 4 female, aged 52 to 75 years) with acute, hemispheric ischemic stroke were treated with alteplase (recombinant tissue plasminogen activator; 0.9 mg/kg according to National Institute of Neurological Disorders and Stroke protocol) within 3 hours of onset of symptoms. At the beginning of thrombolysis, cortical cerebral blood flow ([(15)O]H(2)O) and FMZ binding were assessed by positron emission tomography (PET). Those early PET findings were related to the change in neurological deficit (National Institutes of Health Stroke Scale) and to the extent of cortical damage on MRI or CT 3 weeks after the stroke. RESULTS: Hypoperfusion was observed in all cases, and in 8 patients the values were below critical thresholds estimated at 12 mL/100 g per minute, comprising 1 to 174 cm(3) of cortical tissue. Substantial reperfusion was seen in most of these regions 24 hours after thrombolysis. In 4 cases, distinct areas of decreased FMZ binding were detected. Those patients suffered permanent lesions in cortical areas corresponding to their FMZ defects (112 versus 146, 3 versus 3, 2 versus 1, and 128 versus 136 cm(3)). In the other patients no morphological defects were detected on MRI or CT, although blood flow was critically decreased in areas ranging in size up to 78 cm(3) before thrombolysis. CONCLUSIONS: These findings suggest that imaging of benzodiazepine receptors by FMZ PET distinguishes between irreversibly damaged and viable penumbra tissue early after acute stroke.  相似文献   
54.
55.
Hormonal imprinting takes place perinatally when a hormone and its maturing target receptor meet. As a consequence of imprinting the receptor accomplishes its maturation reaching the binding capacity characteristic to the adult age. In this critical period the presence of foreign molecules which are able to bind to the receptor can cause faulty imprinting with life-long consequences. In the recent years it was cleared that not only receptors are influenced by faulty imprinting, however, also the hormone production of the given cell. In addition imprinting was provoked at non-perinatal periods (adolescence and adult age) in cytogenic organs. In the present experiment the prolonged effect of a non-perinatal imprinting by an antihistamine to the histamine content of white blood cells and glucocorticoid receptors of liver and thymus was studied. Two weeks after 3-day terfenadine treatment at weaning, flow cytometry of peritoneal cells and blood lymphocytes for histamine, and receptor kinetic analysis of dexamethasone binding were done. Histamine content of blood lymphocytes and glucocorticoid receptor density of liver cells were significantly decreased. This means that a short treatment with a H(1)-receptor blocker antihistamine durably influences physiological indexes which were not known till now. This means that not only the acute effects, but the prolonged side-effects must be considered.  相似文献   
56.
PURPOSE: Methyl-[11C]L-methionine ([11C]MET) positron emission tomography (PET) in brain tumors reflects amino acid transport and has been shown to be more sensitive than magnetic resonance imaging in stereotactic biopsy planning. It remains unclear whether the increased [11C]MET uptake is limited to solid tumor tissue or even detects infiltrating tumor parts. EXPERIMENTAL DESIGN: In 30 patients, a primary or recurrent brain tumor was suspected on magnetic resonance imaging. Patients were investigated with [11C]MET-PET before stereotactic biopsy. The biopsy trajectories were plotted into the [11C]MET-PET images with a newly designed C-based software program. The exact local [11C]MET uptake was determined within rectangular regions of interest of 4 mm in width and length aligned with the biopsy specimen. Individual histologic specimens were rated for the presence of solid tumor tissue, infiltration area, and nontumorous tissue changes. RESULTS: Receiver operating characteristics analysis demonstrated a sensitivity of 87% and specificity of 89% for the detection of tumor tissue at a threshold of 1.3-fold [11C]MET uptake relative to normal brain tissue. At this threshold, only 13 of 100 tumor positive specimen were false negative mainly in grade 2 astrocytoma. In grade 2 astrocytoma, mean [11C]MET uptake in the infiltration area was significantly higher than in solid tumor tissue (P < 0.003). CONCLUSIONS: [11C]MET-PET detects solid parts of brain tumors, as well as the infiltration area at high sensitivity and specificity. High [11C]MET uptake in infiltrating tumor of astrocytoma WHO grade 2 reflects high activity in this tumor compartment. Molecular imaging, with [11C]MET, will guide improved management of patients with brain tumors.  相似文献   
57.
PURPOSE: To develop a genome-based classification scheme for clear-cell sarcoma (CCS), also known as melanoma of soft parts (MSP), which would have implications for diagnosis and treatment. This tumor displays characteristic features of soft tissue sarcoma (STS), including deep soft tissue primary location and a characteristic translocation, t(12;22)(q13;q12), involving EWS and ATF1 genes. CCS/MSP also has typical melanoma features, including immunoreactivity for S100 and HMB45, pigmentation, MITF-M expression, and a propensity for regional lymph node metastases. MATERIALS AND METHODS: RNA samples from 21 cell lines and 60 pathologically confirmed cases of STS, melanoma, and CCS/MSP were examined using the U95A GeneChip (Affymetrix, Santa Clara, CA). Hierarchical cluster analysis, principal component analysis, and support vector machine (SVM) analysis exploited genomic correlations within the data to classify CCS/MSP. RESULTS: Unsupervised analyses demonstrated a clear distinction between STS and melanoma and, furthermore, showed that CCS/MSP cluster with the melanomas as a distinct group. A supervised SVM learning approach further validated this finding and provided a user-independent approach to diagnosis. Genes of interest that discriminate CCS/MSP included those encoding melanocyte differentiation antigens, MITF, SOX10, ERBB3, and FGFR1. CONCLUSION: Gene expression profiles support the classification of CCS/MSP as a distinct genomic subtype of melanoma. Analysis of these gene profiles using the SVM may be an important diagnostic tool. Genomic analysis identified potential targets for the development of therapeutic strategies in the treatment of this disease.  相似文献   
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59.
Pelvis-shoulder dysplasia is a rare focal skeletal dysostosis. We present the long-term follow-up of a patient with this condition. This patient has severe pelvic dysplasia but no involvement of the scapulae or clavicles. Despite the severity of the pelvic dysplasia, this man is able to function well. This is the fifth case of pelvis-shoulder dysplasia reported, but the only one documenting follow-up into adulthood. Received: 16 July 1997 Accepted: 4 February 1998  相似文献   
60.
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