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71.
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Infection with Dicrocoelium dendriticum in humans is rarely reported in the medical literature. This liver fluke, which commonly infects ruminants, has a complex life cycle with two intermediate hosts--the land snail and the ant. True human infection occurs by ingestion of the second intermediate host, but spurious infections have occurred after consumption of undercooked animal liver. The present report describes a patient with active Crohn's disease whose stool contained D dendriticum eggs. A brief discussion of the medical literature is presented.  相似文献   
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This short review article discusses methods and results of oncogene research in yeast. Current knowledge of the sequence, expression and biological function of ras-homologous genes of the yeast Saccharomyces cerevisiae is presented, as well as the implications of these findings for oncogene research in mammals. We review recent examples of highly conserved eukaryotic genes involved in growth control and mitosis control, including recent work from our own laboratories.  相似文献   
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BACKGROUND: Amantadine (1-adamantylamine) is used for treatment of influenza, hepatitis C, parkinsonism, and multiple sclerosis. Current amantadine analysis by HPLC or gas chromatography (GC) requires a laborious sample pretreatment with extraction and/or derivatization steps. We established an LC-MS/MS method without protein precipitation, centrifugation, extraction and derivatization steps. MATERIAL AND METHODS: 50 microl sample+50 microl of 0.4 mg/l 1-(1-adamantyl)pyridinium bromide as internal standard+1000 microl water (96-well plate). Of this 25 microl+500 microl water (96-well plate; final serum dilution 1:462). LC-MS/MS: Surveyor MS pump, Autosampler, triple-quadrupole TSQ Quantum mass spectrometer (Thermo Electron). Autosampling: 2 microl of each sample. Chromatography: isocratic water/acetonitrile (60/40 v/v) with 5 g/l formic acid, flow rate 0.2 ml/min, run time 3 min, Phenomenex Luna C8(2) (100 x 2.0 mm (i.d.); 3-microm bead size) column. Mass spectrometry: electrospray atmospheric pressure ionization, positive ion and selective reaction monitoring mode, ion transitions m/z 152.0-->135.1 (at 22 eV amantadine) and 214.1-->135.1 (at 26 eV internal standard). RESULTS: Calibration curves were constructed with spiked serum samples (amantadine 50-1000 microg/l, r>0.99). No carry over (5000 microg/l). No ion suppression with retention times similar to those of amantadine (1.8 min) and the internal standard (2.1 min). Detection limit 20 mg/l, linearity 20-5000 mg/l, intra-assay/inter-assay CV<6%/<8%, recovery 99-101%. Method comparison: LC-MS/MS=1.23 x GC-45 (Passing-Bablok regression). No significant bias between GC and LC-MS/MS (Bland-Altman plot). CONCLUSION: We consider the sample pretreatment without deproteination, derivatization and centrifugation steps and the specificity of the tandem mass spectrometry as the most important points of our amantadine analysis method.  相似文献   
76.
BACKGROUND: The Toll-like receptor 4 (TLR4) is involved in immune response to endotoxin as well as the pathogenesis of atherosclerosis. The TLR4 gene was shown to carry a single-nucleotide polymorphism (A896G). We developed a rapid-cycle polymerase chain reaction (PCR) which allows for rapid genotyping and, therefore, may be useful in clinical risk assessment. METHODS: Fluorescently labeled oligonucleotide hybridization probes were designed for the LightCycler instrument. A PCR product was generated in a single reaction followed by melting point analysis. Ninety-three German Caucasians were genotyped. The interleukin-1beta (IL-1beta) response to endotoxin was assessed after whole blood stimulation with endotoxin according to TLR4 genotypes. RESULTS: The method suggested by us is a time-saving technique requiring no additional manual steps. Frequencies of the A and G allele were 0.95 and 0.05, respectively. The study population was in Hardy-Weinberg equilibrium. The specificity of the method was confirmed by sequencing. The IL-1beta levels were lower in carriers of the G allele. CONCLUSIONS: This PCR assay is a rapid and reliable technique for TLR4 genotyping.  相似文献   
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Low levels of full-length survival motor neuron (SMN) protein cause the motor neuron disease, spinal muscular atrophy (SMA). Although motor neurons undoubtedly contribute directly to SMA pathogenesis, the role of muscle is less clear. We demonstrate significant disruption to the molecular composition of skeletal muscle in pre-symptomatic severe SMA mice, in the absence of any detectable degenerative changes in lower motor neurons and with a molecular profile distinct from that of denervated muscle. Functional cluster analysis of proteomic data and phospho-histone H2AX labelling of DNA damage revealed increased activity of cell death pathways in SMA muscle. Robust upregulation of voltage-dependent anion-selective channel protein 2 (Vdac2) and downregulation of parvalbumin in severe SMA mice was confirmed in a milder SMA mouse model and in human patient muscle biopsies. Molecular pathology of skeletal muscle was ameliorated in mice treated with the FDA-approved histone deacetylase inhibitor, suberoylanilide hydroxamic acid. We conclude that intrinsic pathology of skeletal muscle is an important and reversible event in SMA and also suggest that muscle proteins have the potential to act as novel biomarkers in SMA.  相似文献   
79.
Basaloid squamous cell carcinoma (BSCC) and carcinosarcoma of the esophagus are rare entities, making up fewer than 2% of esophageal malignancies. Comparative genomic hybridization (CGH) in 1 case of BSCC and 2 cases of carcinosarcoma and subsequent array CGH in 1 case each of BSCC and carcinosarcoma revealed common chromosomal gains at 2p25.3-2p12, 7q21.3-7q22.3, and 11q13.2-11q13.4. Chromosomal losses at 13q31qter were observed in both carcinosarcomas. In addition, progression of genomic instability from in situ to invasive carcinosarcoma could be demonstrated by using array CGH. Our observations suggest a common genetic origin of BSCC and carcinosarcoma.  相似文献   
80.
Exposing animals to brief hypoxic periods leads to neuroprotective ischemic tolerance termed preconditioning. This phenomenon is well documented in the brain, but the underlying mechanisms require further elucidation. As nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) are important mediators of maintaining homeostatic conditions in the adult nervous system in terms of physiological and pathophysiological processes, we hypothesized that hypoxic preconditioning might modulate serum neurotrophin concentrations. Hypoxia was induced for 30 min in 14 healthy young men resulting in a constant blood oxygen saturation of 75%. Hyperinsulinemic euglycemic clamps were performed and serum concentrations of BDNF and NGF were measured at baseline, directly after the intervention, and at the end of the session. Overall, serum BDNF concentrations decreased over time by maximally 35% (P = 0.001) while in contrast NGF concentrations remained unchanged. Acute hypoxia alleviated the decrease of BDNF resulting in higher BDNF concentrations as compared to normoxic control (P < 0.01). Our findings show that acute hypoxia results in significantly higher serum BDNF concentrations pointing to a potential role of BDNF in the underlying mechanism of hypoxic preconditioning. Based on its neuroprotective properties, BDNF may be of high clinical relevance for therapeutic options in ischemic neurovascular diseases.  相似文献   
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