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1.
EEG in Creutzfeldt-Jakob disease. 总被引:2,自引:0,他引:2
Electroecenphalography (EEG) is an integral part of the diagnostic process in patients with Creutzfeldt-Jakob disease (CJD). The EEG has therefore been included in the World Health Organisation diagnostic classification criteria of CJD. In sporadic CJD (sCJD), the EEG exhibits characteristic changes depending on the stage of the disease, ranging from nonspecific findings such as diffuse slowing and frontal rhythmic delta activity (FIRDA) in early stages to disease-typical periodic sharp wave complexes (PSWC) in middle and late stages to areactive coma traces or even alpha coma in preterminal EEG recordings. PSWC, either lateralized (in earlier stages) or generalized, occur in about two-thirds of patients with sCJD, with a positive predictive value of 95%. PSWC occur in patients with methionine homozygosity and methionine/valine heterozygosity but only rarely in patients with valine homozygosity at codon 129 of the prion protein gene. PSWC tend to disappear during sleep and may be attenuated by sedative medication and external stimulation. Seizures are an uncommon finding, occurring in less than 15% of patients with sCJD. In patients with iatrogenic CJD, PSWC usually present with more regional EEG findings corresponding to the site of inoculation of the transmissible agent. In genetic CJD, PSWC in its typical form are uncommon, occurring in about 10%. No PSWC occur in EEG recordings of patients with variant CJD. 相似文献
2.
Ittel TH; Steinhausen C; Kislinger G; Kinzel S; Nolte E; Sieberth HG 《Nephrology, dialysis, transplantation》1997,12(7):1369-1375
BACKGROUND: Developments in accelerator mass spectrometry (AMS) now permit
the determination of femtogram amounts of 26Al in blood and in various
tissues with good precision and free of external contamination. METHODS: In
the present study we used trace quantities of 26Al to investigate the
intestinal absorption and compartmentalization of aluminium in rats with
renal failure (Nx, 5/6 nephrectomy) and in pair- fed controls (C). Single
oral doses of 20 ng 26Al were administered to six animals in each group
and, subsequently, 24-h post-load 26Al was analysed in serum, urine, bone,
liver, and spleen by means of AMS. RESULTS: Serum concentrations of 26Al
were significantly lower in uraemic rats compared to controls, whereas
urinary excretion was comparable (Nx, 7.11 +/- 5.78 pg/day vs C, 9.46 +/-
6.10 pg/day), suggesting a higher fraction of ultrafiltrable serum 26Al in
uraemia. The target tissues of cellular transferrin-mediated 26Al uptake,
liver and spleen, tended to show a larger degree of aluminium accumulation
in controls (0.26 +/- 0.31 pg/g vs Nx, 0.14 +/- 0.10 pg/g and 0.37 +/- 0.27
pg/g vs Nx, 0.25 +/- 0.27 pg/g respectively). In contrast, in bone, a site
of extracellular aluminium deposition, 26Al concentrations were more
elevated in uraemia (1.22 +/- 0.59 pg/g vs C: 0.68 +/- 0.30 pg/g).
Estimated total 26Al accumulation in all measured target tissues was
significantly higher in uraemic rats (28.15 +/- 9.90 pg vs C: 17.03 +/-
7.03 pg) and total recovery of 26Al from tissue and urine was 26.58 +/-
6.74 pg in controls and 35.75 +/- 7.03 pg in uraemic animals, suggesting a
fractional absorption of 0.133% and 0.175% respectively. CONCLUSIONS: Our
data suggest that fractional absorption from a dietary level dose of 26Al
is about 0.13%. Compartmentalization occurs in transferrin-dependent target
tissues such as liver and spleen; however, in quantitative terms
extracellular deposition in bone is more important. Uraemia has a
significant effect on the intestinal absorption and compartmentalization of
aluminium. It enhances fractional absorption and increases subsequent
extracellular deposition of aluminium in bone. However, at the same time
uraemia does not increase transferrin-dependent cellular accumulation of
aluminium in liver and spleen.
相似文献
3.
Laser Treatment of Endobronchial Lesions 总被引:2,自引:0,他引:2
4.
OBJECTIVE: To test whether increasing synchronization of neuronal activity might be causally related to seizure termination. METHODS: Neuronal synchronization was assessed by the relative changes of the eigenvalue spectrum of the equal-time correlation matrix computed from a short window sliding along multi-channel EEGs, recorded with either intracranial or surface electrodes. RESULTS: Synchronization dynamics of six status epilepticus EEG recordings from six patients were assessed. In all six recordings EEG synchronization fluctuated around relatively low levels during ongoing epileptiform activity. Synchronization only persistently increased before, or in one case, at the end of status epilepticus. Ongoing seizure activity stopped without pharmacological intervention in one patient. In four of the five other cases, the persistent increase of synchronization followed administration of anticonvulsant drugs. CONCLUSIONS: Our findings support the hypothesis that increasing synchronization of neuronal activity may be considered as an emergent self-regulatory mechanism for seizure termination. SIGNIFICANCE: The traditional concept is challenged that increasing neuronal synchronization during epileptic seizures is always pathological and should be suppressed. On the contrary, our findings imply that therapeutic interventions to increase synchronization during seizures might be beneficial. 相似文献
5.
Endometrial and colorectal tumors from patients with hereditary nonpolyposis colon cancer display different patterns of microsatellite instability
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Kuismanen SA Moisio AL Schweizer P Truninger K Salovaara R Arola J Butzow R Jiricny J Nyström-Lahti M Peltomäki P 《The American journal of pathology》2002,160(6):1953-1958
The colorectum and uterine endometrium are the two most commonly affected organs in hereditary nonpolyposis colon cancer (HNPCC), but the genetic basis of organ selection is poorly understood. As tumorigenesis in HNPCC is driven by deficient DNA mismatch repair (MMR), we compared its typical consequence, instability at microsatellite sequences, in colorectal and endometrial cancers from patients with identical predisposing mutations in the MMR genes MLH1 or MSH2. Analysis of non-coding (BAT25, BAT26, and BAT40) and coding mononucleotide repeats (MSH6, MSH3, MLH3, BAX, IGF2R, TGF beta RII, and PTEN), as well as MLH1- and MSH2-linked dinucleotide repeats (D3S1611 and CA7) revealed significant differences, both quantitative and qualitative, between the two tumor types. Whereas colorectal cancers displayed a predominant pattern consisting of instability at the BAT loci (in 89% of tumors), TGF beta RII (73%), dinucleotide repeats (70%), MSH3 (43%), and BAX (30%), no such single pattern was discernible in endometrial cancers. Instead, the pattern was more heterogeneous and involved a lower proportion of unstable markers per tumor (mean 0.27 for endometrial cancers versus 0.45 for colorectal cancers, P < 0.001) and shorter allelic shifts for BAT markers (average 5.1 bp for unstable endometrial cancers versus 9.3 bp for colorectal cancers, P < 0.001). Among the individual putative "target" loci, PTEN instability was associated with endometrial cancers and TGF beta RII instability with colon cancers. The different instability profiles in endometrial and colorectal cancers despite identical genetic predisposition underlines organ-specific differences that may be important determinants of the HNPCC tumor spectrum. 相似文献
6.
Johann Kaspar Lieberwirth Pascal Joset Anja Heinze Julia Hentschel Anja Stein Antonella Iannaccone Katharina Steindl Alma Kuechler Rami Abou Jamra 《European journal of human genetics : EJHG》2021,29(5):808
Perinatal mortality is a heavy burden for both affected parents and physicians. However, the underlying genetic causes have not been sufficiently investigated and most cases remain without diagnosis. This impedes appropriate counseling or therapy. We describe four affected children of two unrelated families with cardiomyopathy, hydrops fetalis, or cystic hygroma that all deceased perinatally. In the four patients, we found the following homozygous loss of function (LoF) variants in SLC30A5 NM_022902.4:c.832_836del p.(Ile278Phefs*33) and NM_022902.4:c.1981_1982del p.(His661Tyrfs*10). Knockout of SLC30A5 has previously been shown a cardiac phenotype in mouse models and no homozygous LoF variants in SLC30A5 are currently described in gnomAD. Taken together, we present SLC30A5 as a new gene for a severe and perinatally lethal form of cardiomyopathy.Subject terms: Cardiovascular diseases, Development, Medical genetics, Medical genomics 相似文献
7.
Barbara Riond Marina L. Meli Ueli Braun Peter Deplazes Kaspar Joerger Rudolf Thoma Hans Lutz Regina Hofmann-Lehmann 《Comparative clinical pathology》2008,17(3):171-177
An outbreak of a fatal haemolytic anaemia in a dairy herd of cattle in Switzerland was shown to be associated with infections
with five vector-borne pathogens, namely Anaplasma marginale, A. phagocytophilum, Babesia bigemina, a Theileria spp belonging to the buffeli/sergenti/orientalis complex and haemotrophic Mycoplasma spp. The latter three had not been documented before this outbreak in Switzerland. To characterise the haematological and blood
chemical changes in these unique cows, packed cell volume was determined in all 286 blood samples, blood smears, and complete
haematology were performed from 285 and 173 blood samples, respectively, and biochemical parameters were assayed in 105 serum
samples. Regenerative anaemia was the key sign of illness. Red blood cells of anaemic cattle were hypochromic and macrocytic.
Anaemic animals had reduced platelet cell counts and increased total white cell counts. In addition, increased serum bilirubin,
blood aspartate aminotransferase, gamma glutamyltransferase, glutamic dehydrogenase and blood urea nitrogen and decreased
magnesium, calcium and albumin levels were found in anaemic cattle when compared to animals with normal packed cell volume.
Most changes could not be attributed to a single infection. A. marginale seemed to be important in causing the outbreak, but co-infections may have aggravated the disease development and clinical
signs. Thus, when encountering cattle with haemolytic anaemia, all of the mentioned pathogens should be included as differential
diagnosis. 相似文献
8.
The shift from inpatient care to the ambulatory sector is a central aspiration of European health systems. Despite demonstrated benefits, health reforms have struggled to realize their potential. In this context, we discuss recent hospital sector reforms in Switzerland and analyze the content, process, and role of evidence in the recent introduction of policies to substitute inpatient care with ambulatory care. The prevailing payment system incentivized hospitals to provide unnecessary and costly inpatient services, but federal reform on tariff structures was deemed politically unfeasible. Instead, driven by the pressure to contain costs, cantonal and federal health authorities began to deny reimbursement for selected inpatient procedures in 2017. These regulatory measures were effective in reducing inpatient admissions and health care costs. This case study illustrates that clear, simple messages about hospital sector reform can raise awareness of the need for change. However, the evidence used in the policy process was limited and not critically reviewed. Stakeholders used long-standing international comparisons of inpatient substitution potential to legitimize policies, but not to develop them. The analysis restates the importance of inter- and intranational comparative analyses and institutions such as health observatories and suggests aligning health system governance more proactively with international developments. 相似文献
9.
Christoph A. Binder Herminia Mi?o de Kaspar V. Klau? Anselm Kampik 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1999,247(7):663-667
Background: Most germs causing postoperative endophthalmitis derive from the conjunctival bacterial normal flora. Postoperative endophthalmitis
is often induced by staphylococcal germs. The application of polyvidone-iodine solution to the conjunctiva is one possibility
to reduce potential endophthalmitis-causing bacteria. The aim of this study was to evaluate the effectiveness of 1 % polyvidone-iodine
solution concerning the reduction of colonization with staphylococci in the course of intraocular surgery. This is to evaluate
the effectiveness of 1 % polyvidone-iodine solution concerning coagulase-negative and positive staphylococci. 相似文献
10.
The cell activity of human bone derived cell cultures was studied after mechanical stimulation by cyclic strain at a magnitude occurring in physiologically loaded bone tissue. Monolayers of subconfluently grown human bone derived cells were stretched in rectangular silicone dishes with cyclic uniaxial movement along their longitudinal axes. Strain was applied over two days for 30 min per day with a frequency of 1 Hz and a strain magnitude of 1000 mustrain. Cyclic stretching of the cells resulted in an increased proliferation (10-48%) and carboxyterminal collagen type I propeptide release (7-49%) of human cancellous bone derived osteoblasts while alkaline phosphatase activity and osteocalcin release were significantly reduced by 9-25% and 5-32% respectively. These results demonstrate that cyclic strain at physiologic magnitude leads to an increase of osteoblast activities related to matrix production while those activities which are characteristic for the differentiated osteoblast and relevant for matrix mineralization are decreased. 相似文献