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CSF detection of the 14-3-3 protein in unselected patients with dementia   总被引:9,自引:0,他引:9  
OBJECTIVE: To determine the usefulness of the 14-3-3 test in patients with dementia of various causes. BACKGROUND: Recent reports have suggested that the detection of the 14-3-3 protein in the CSF of patients with Creutzfeldt--Jakob disease is a highly sensitive and specific marker of the disease that might be used as a diagnostic criterion. We examined the validity of this test when applied to a cohort of unselected patients prospectively examined for an ongoing dementing process. METHODS: One hundred patients underwent an extensive neurologic examination for dementia, including a CSF 14-3-3 protein immunoblotting assay. Final clinical diagnoses were compared with the qualitative results of the test, and statistical measures of test validity were carried out. RESULTS: We found a positive test in 14 of 100 patients, only two of whom had definite Creutzfeldt--Jakob disease. Positive results were found in patients with various degenerative dementias, including AD (4), frontotemporal dementia (2), and dementia with Lewy body (1), and in patients with vascular dementia (1), carcinomatous meningitis (1), and anoxic encephalopathy (1). In two other positive patients, the dementia could not be confidently classified. Sensitivity, specificity, and negative predictive value were fairly good, but positive predictive value was poor. Similar results were found independently of the disease duration. There was no correlation between intensity nor pattern of the 14-3-3 protein expression and diagnosis. CONCLUSIONS: The 14-3-3 test is not valid for discriminating between Creutzfeldt--Jakob disease and non-Creutzfeldt--Jakob disease in unselected patients with dementia. Positive results are found in various degenerative and secondary, prion-unrelated dementias.  相似文献   
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Our objective was to study how invasive mechanical ventilation impairs cardiac output (CO) in children and adults. Although the application of continuous positive airway pressure (CPAP) is widely practiced in neonatal intensive care, its hemodynamic consequences have not yet been investigated. A prospective study to assess the hemodynamic effects was conducted in 21 preterm infants < 1500 g using two-dimensional M-mode and pulsed Doppler echocardiography during and 1 hour after discontinuation of nasal CPAP (n-CPAP). Gestational age was 28.0 +/- 1.9 weeks (mean +/- standard deviation); birthweight, 1000 +/- 238 g; age at study entry, 200 +/- 155 hours; total maintenance fluid, 154 +/- 42 mL/kg/day; and n-CPAP level, 4.4 +/- 0.9 cm H(2)O. None of the infants received inotropic support, and n-CPAP did not cause any significant difference in the parameters measured: stroke volume, 3.1 +/- 1.0 mL (with n-CPAP) versus 3.1 +/- 1.0 mL (without n-CPAP); cardiac output, 487 +/- 156 mL/minute versus 500 +/- 176 mL/minute; left ventricular diastolic diameter, 1.22 +/- 0.15 cm versus 1.24 +/- 0.14 cm; fractional shortening, 0.30 +/- 0.05% versus 0.29 +/- 0.04%; and aortic velocity-time integral, 8.64 +/- 1.80 cm versus 8.70 +/- 1.65 cm. The n-CPAP level did not influence CO; n-CPAP (up to 7 cm H (2)O) has no echocardiographically detectable hemodynamic effect in preterm infants. Our data imply there is no need to withhold n-CPAP support to prevent circulatory compromise in these infants.  相似文献   
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A complicated case of iatrogenic ureterovaginal fistula in a 56-year-old woman after laparoscopic-assisted vaginal hysterectomy, which persisted after several attempts of repair including ureterocystoneostomy, is presented. Accurate radiologic work-up enabled us to identify a refluxing ureteral stump, which was not ligated at the time of ureterocystoneostomy, as the origin of urinary leakage. Surgical principles that should be adhered to when managing such complex cases to obtain successful long-lasting outcome are described.  相似文献   
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Both the phytopathogenic fungus Ramularia collo-cygni and the hyperparasite R. uredinicola biosynthesize a number of red and yellow anthraquinone derivatives called rubellins. The new compounds uredinorubellins I and II, which were isolated from R. uredinicola, contribute to understanding the biosynthesis pathway that leads from simple anthraquinones to the rubellins. In addition, we isolated for the first time such simple compounds as chrysophanol and helminthsporin from both Ramularia species. A blue compound isolated from the mycelium of R. collo-cygni was revealed to be a unique 9,4-anthracenedione derivative. Structure elucidation by (1)H and (13)C NMR of the new but unstable compound caeruleoramularin was possible only by feeding the fungus different labeled (13)C acetates. The photodynamic activity of the uredinorubellins was comparable to rubellin D, whereas chrysophanol and caeruleoramularin did not display such activity.  相似文献   
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A large number of short tandem repeat (STR) markers spanning the entire human X chromosome have been described and established for use in forensic genetic testing. Due to their particular mode of inheritance, X-STRs often allow easy and informative haplotyping in kinship analyses. Moreover, some X-STRs are known to be tightly linked so that, in combination, they constitute even more complex genetic markers than each STR taken individually. As a consequence, X-STRs have proven particularly powerful in solving complex cases of disputed blood relatedness. However, valid quantification of the evidence provided by X-STR genotypes in the form of likelihood ratios requires that the recombination rates between markers are exactly known. In a collaborative family study, we used X-STR genotype data from 401 two- and three-generation families to derive valid estimates of the recombination rates between 12 forensic markers widely used in forensic testing, namely DXS10148, DXS10135, DXS8378 (together constituting linkage group I), DXS7132, DXS10079, DXS10074 (linkage group II), DXS10103, HPRTB, DXS10101 (linkage group III), DXS10146, DXS10134 and DXS7423 (linkage group IV). Our study is the first to simultaneously allow for mutation and recombination in the underlying likelihood calculations, thereby obviating the bias-prone practice of excluding ambiguous transmission events from further consideration. The statistical analysis confirms that linkage groups I and II are transmitted independently from one another whereas linkage groups II, III and IV are characterised by inter-group recombination fractions that are notably smaller than 50%. Evidence was also found for recombination within all four linkage groups, with recombination fraction estimates ranging as high as 2% in the case of DXS10146 and DXS10134.  相似文献   
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