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Johannes Brettschneider Axel Petzold Sigurd D Süssmuth Georg B Landwehrmeyer Albert C Ludolph Jan Kassubek Hayrettin Tumani 《Movement disorders》2006,21(12):2224-2227
We aimed to evaluate the potential of the cerebrospinal fluid (CSF) axonal damage biomarker NfH(SMI35) in the laboratory-supported differential diagnosis of parkinsonian syndromes. Patients with idiopathic Parkinson's disease (PD; n = 22), multiple-system atrophy (MSA; n = 21), progressive supranuclear palsy (PSP; n = 21), corticobasal degeneration (CBD; n = 6), and age-matched controls (n = 45) were included. CSF levels of NfH(SMI35) were measured using ELISA. Levels of CSF NfH(SMI35) were elevated in PSP compared to PD and controls (P < 0.05 each). They were also significantly higher in MSA than in PD and controls (P < 0.05 each). NfH(SMI35) differentiated PD from PSP with a sensitivity of 76.5% and a specificity of 94.4%. Axonal damage as measured by CSF NfH(SMI35) is most prominent in the more rapidly progressive syndromes PSP and MSA as compared to PD or CBD. CSF NfH(SMI35) may therefore be of some value for the laboratory-supported differential diagnosis of atypical parkinsonian syndromes. 相似文献
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Neurotoxicity and carcinogenicity of N-methylolacrylamide in F344 rats and B6C3F1 mice 总被引:1,自引:0,他引:1
J R Bucher J Huff J K Haseman S L Eustis A Peters J D Toft 《Journal of toxicology and environmental health》1990,31(3):161-177
Toxicology and carcinogenicity studies of N-methylolacrylamide were conducted by administering the chemical by gavage in water to both sexes of F344/N rats and B6C3F1 mice 5 times per week for 16 d, 13 wk, or 2 yr. In 16-d studies, rats receiving doses of 200 mg/kg or higher and mice receiving 400 mg/kg died. In 13-wk studies, all rats given 100 mg/kg or higher doses died. Rats receiving 50 mg/kg or higher doses developed hindlimb ataxia progressing to paralysis. In neurobehavioral assessments, decreased forelimb and hindlimb grip strength occurred in rats at doses as low as 12.5 mg/kg. Landing footspread was also increased in dosed rats compared to controls. Axon filament and myelin sheath degeneration in the spinal cord and/or peripheral nerves occurred in rats receiving doses of 25 mg/kg or higher. Necrosis in the granular cell layer of the cerebellum was seen in rats given 200 mg/kg. Mice receiving 200 mg/kg in 13-wk studies died. Decreased grip strength was noted in mice at doses as low as 25 mg/kg, and rotarod performance was also affected by N-methylolacrylamide administration, but no neuropathology was seen microscopically. Testicular weights were decreased at doses as low as 12.5 mg/kg, and hepatocellular necrosis, thymic lymphocyte necrosis, and hemorrhage, necrosis, and mineralization of the zona reticularis of the adrenal gland were seen in mice that died (200 mg/kg). In 2-yr studies, survival and weight gains in male and female rats receiving doses of 6 or 12 mg/kg/d were minimally affected. No biologically important clinical signs or neoplastic or nonneoplastic lesions were attributed to N-methylolacrylamide administration to rats, suggesting that higher doses could have been tolerated. In mice, survival was not different between dosed and control groups (0, 25, or 50 mg/kg/d). Body weights were higher by as much as 25% in dosed compared to control groups. No compound-related clinical signs were observed, but increases in neoplasms of the harderian gland, liver, and lung were clearly related to chemical administration in both sexes of mice. Benign granulosa-cell neoplasms of the ovary were also increased in dosed female mice. 相似文献
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Jens Toft Birger Hesse Alan Rabøl Steen Carstensen Samir Ali 《European journal of nuclear medicine and molecular imaging》1997,24(4):409-414
Reference data files support the evaluation of myocardial perfusion single-photon emission tomography (SPET). The aim of this study was to create a large reference data base for technetium-99m sestamibi SPET, age and gender matched to the general patient population. One hundred and twenty-eight healthy volunteers (76 males and 52 females) with a likelihood of coronary artery disease of less than 5% underwent rest and maximal exercise99mTc-sestamibi SPET with a 2-day protocol and 180° elliptical rotation. The normalized activity values of99mTc-sestamibi in the inferior wall differed significantly between men and women. Age variations were found for men in the anterior wall. Normalized activity values in all four walls were strikingly similar during rest and stress. Our results suggest that the use of reference files in99mTc-sestamibi SPET requires a gender- and, for males, possibly an age-matched reference population. Different reference files at rest and during stress might not be necessary. 相似文献
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PURPOSE: The low incidence of mortality and major morbidity in anesthesia makes it difficult to study the pattern of potential accidents and to develop preventive strategies. Anesthetic 'near-misses', however, occur more frequently. Using data from a simple routine-based system of problem reporting, we have analyzed the pattern and causes of serious non-fatal problems, in order to improve preventive strategies. METHODS: We prospectively recorded anesthesia-related information from all anesthetics for five years. The data included intraoperative problems, which were graded into four levels, according to severity. We analyzed only the serious nonfatal problems, which were sorted according to clinical presentation, and also according to which factor was most important in the development of the problem. We assessed any untoward consequences for the patient, and whether the problems could have been prevented. RESULTS: Serious problems were recorded in 315 cases out of 83,844 (0.4%). Anesthesia was considered the major contributing factor in 111 cases. Difficult intubation, difficult emergence from general anesthesia, allergic reactions, arrhythmia and hypotension were the dominating problems. Twenty-six anesthesia related problems resulted in changes in level of postoperative care, and one patient later died in the intensive care unit after anaphylactic shock. Eighty-two problems could have been prevented by simple strategies. CONCLUSION: Analysis of serious nonfatal problems during anesthesia may contribute to improved preventive strategies. Data from a routine-based system are suitable for this type of analysis. Intubation, emergence, arrhythmia, hypotension and anaphylaxis cause most serious problems, and should be the object of preventive strategies. 相似文献
7.
H. C. Lou P. B. Toft J. Andresen I. Mikkelsen B. Olsen F. Güttler S. Wieslander O. Henriksen 《Journal of inherited metabolic disease》1992,15(5):687-695
Summary The study included 16 adolescents with optimally controlled hyperphenylalaninaemia (McKusick 26160), of whom six did not require treatment according to conventional criteria. All except the two patients with lowest median serum phenylalanine level throughout childhood (most values at 200–300 µmol/L) had white matter abnormalities detectable with magnetic resonance imaging. The lesions were particularly prominent in the watershed regions between the posterior and middle cerebral arteries. In most patients with moderate or severe hyperphenylalaninaemia frontal white matter lesions were present as well. Normal proton magnetic resonance spectra indicated that the lesions were stable. Occipital EEG abnormalities were frequent, and deficient performance on a pattern-recognition test was a characteristic neuropsychological finding. Serum phenylalanine levels at about 300 µmol/L or below throughout childhood and early adolescence may be required to avoid lesions. The present study demonstrates the limitations of even an optimally controlled dietary regimen in hyperphenylalaninaemia. 相似文献
8.
Peter Regitnig Ferdinand Ploner Martina Maderbacher Sigurd F Lax 《Modern pathology》2004,17(5):597-602
Local recurrence of bilateral breast carcinomas is rare, but of biological interest, since it is unclear as to which tumor the local recurrence is related to, the ipsilateral or the contralateral, or whether it is an independent neoplasm. The aim of this study was to investigate the genetic relationship of bilateral breast carcinomas to each other and to their local recurrences. Eight cases of bilateral breast carcinomas, five with and three without local recurrence were analyzed using a microsatellite assay for 13 microsatellite loci. The presence of loss of heterozygosity and microsatellite instability in the various tumors was used for clonal analysis. All eight bilateral breast carcinomas showed divergent alterations in at least two microsatellite loci, which ruled out a genetic relationship. Four of five local recurrences were genetically related to the ipsilateral tumor and unrelated to the contralateral tumor. Only one local recurrence that occurred 11.8 years after the surgery of an infiltrative lobular carcinoma simultaneously with distant metastases was genetically related to the contralateral breast carcinoma. Although the number of cases in our study is limited, there is evidence that local recurrence of bilateral breast carcinoma frequently arises from the ipsilateral tumor. 相似文献
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Regitnig P Moser R Thalhammer M Luschin-Ebengreuth G Ploner F Papadi H Tsybrovskyy O Lax SF 《The Journal of pathology》2002,198(2):190-197
Local recurrence is a serious complication of breast carcinoma that reduces quality of life and influences prognosis. The aim of this study was to determine whether local recurrences of breast carcinoma are genetically related to the primary tumours. Forty cases of locally recurrent breast carcinomas (median onset: 3.6 years after primary surgery) were analysed: 22 patients had undergone breast-conserving therapy and 18 mastectomy. Eighteen microsatellites on chromosomes 2p, 3p, 5q, 10q, 11p, 11q, 13q, 17q, 17p, 18p were amplified by PCR using fluorescent-labelled primers, automatically detected after polyacrylamide gel electrophoresis and analysed for loss of heterozygosity (LOH) or microsatellite instability (MSI). Follow-up data were available for 39 cases with a median value of 89 months. All LOH and MSI found in the primary tumours were also present in the corresponding recurrences, indicating that they are genetically related to the primary tumours and not secondary malignancies in the same breast. MSI was found in three cases, of which one harboured MSI at more than two loci. The median value of LOH per case was significantly higher in the recurrent (four per case) compared to the primary tumours (two per case; p < 0.001, Mann-Whitney test), reflecting the genotype of tumour progression. Early local recurrence was associated with specific LOH for TP53.15 (p = 0.018, log-rank test) in the primary tumours. LOH on D13S1699 or D17S855 was associated with lymph node metastases (p = 0.024 and p = 0.019, respectively; chi-square test). In addition, tumour grade, lack of oestrogen or progesterone receptor expression, young patient age and early appearance of local recurrence significantly correlated with poor survival. The development of local recurrence despite clear resection margins may result from residual DCIS distant from the invasive carcinoma, homing of circulating tumour cells, or genetically altered, histologically normal breast tissue not immediately adjacent to the invasive carcinoma. 相似文献