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1.
Antibody-mediated rejection (AMR) after liver transplantation is recognized in ABO incompatible and xeno-transplantation, but its role after ABO compatible liver transplantation is controversial. We report a case of ABO compatible liver transplantation that demonstrated clinical, serological and histological signs of AMR without evidence of concurrent acute cellular rejection. AMR with persistently high titers of circulating donor specific antibodies resulted in graft injury with initial centrilobular hepatocyte necrosis, fibroedematous portal expansion mimicking biliary tract outflow obstruction, ultimately resulting in extensive bridging fibrosis. Immunofluorescence microscopy demonstrated persistent, diffuse linear C4d deposits along sinusoids and central veins. Despite intense therapeutic intervention including plasmapheresis, IVIG and rituximab, AMR led to graft failure. We present evidence that an antibody-mediated alloresponse to an ABO compatible liver graft can cause significant graft injury independent of acute cellular rejection. AMR shows distinct histologic changes including a characteristic staining profile for C4d.  相似文献   
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Fetal scalp blood sampling (FSBS), in conjunction with fetal heart rate monitoring, is a method of fetal surveillance that may avoid cesarean delivery of the healthy fetus or indicate the need for immediate delivery of a compromised fetus. Some researchers have recently begun to question the efficacy of FSBS. In this article, three nurse-midwives discuss FSBS as a tool in assessing fetal well-being during labor and consider whether FSBS is a nurse-midwifery procedure.  相似文献   
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The aim of this research was to assess whether common genetic variants within the C-reactive protein gene ( CRP ) are related to the degree of acute rise in plasma C-reactive protein (CRP) levels following an acute coronary syndrome (ACS). While polymorphisms within CRP are associated with basal CRP levels in healthy men and women, less is known about the relationship of such genetic variants and the degree of CRP rise during and after acute ischemia. Plasma CRP is associated with increased rates of recurrent coronary events. We evaluated seven common genetic variants within CRP and assessed their relationship to the degree of rise in CRP levels immediately following an acute coronary syndrome in 1827 European American patients. Variants in the putative promoter region, −757T > C and −286C > T > A, were associated with the highest CRP elevations after ACS. Patients with two copies of the A allele of SNP −286C > T > A had median CRP values of 76.6 mg/L, compared to 11.1 mg/L in patients with no copies of the rare variant (p-value <0.0001), post ACS. The lowest CRP values were found for patients with minor alleles of the exonic 1059G > C and the 3'untranslated region 1846G > A SNPs. For example, patients homozygous for the minor allele of 1059G > C had 71% lower median CRP values than those homozygous for the major allele [3.5 vs 12.0 mg/L, p < 0.0001]. These trends persisted in the chronic stable phase after ischemia had resolved, and after adjustment for infarct size by peak creatinine kinase levels and clinical status by Killip class. Assessment of CRP genetic variants identified patients with higher and lower CRP elevation after acute coronary syndrome.  相似文献   
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Experimental gene therapy is a promising strategy to prevent ischemia-reperfusion (I/R) injury and allograft rejection after lung transplantation, and methods will eventually be needed to characterize pulmonary transgene expression in vivo in humans. Therefore, we studied positron emission tomography (PET) as a means of performing in vivo molecular imaging in rodent models of lung transplantation. Rats were transfected endotracheally with adenovirus encoding a fusion gene of a mutant Herpes simplex virus-1 thymidine kinase and the green fluorescent protein gene (the former serving as an imaging reporter gene). Twenty-four hours after transfection, lungs were transplanted in groups representing normal transplantation, I/R injury and acute allograft rejection. Imaging was obtained either 24 h after transplantation to study reperfusion injury or 4 days after transplantation to study graft rejection. After imaging, lungs were excised and analyzed for thymidine kinase activity. Imaging detected transgene expression in transplanted lungs even in the presence of acute rejection or I/R injury. The PET imaging signal correlated with in vitro lung tissue assays of thymidine kinase activity (r(2) = 0.534). Thus, noninvasive molecular imaging with PET is a feasible, sensitive and quantitative method for characterizing pulmonary transgene expression in experimental lung transplantation.  相似文献   
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Studies were undertaken to define the expression of cytokeratins in normal, hyperplastic and malignant epithelial cells from human prostate. Cytokeratin (CK) polypeptides, separated by two-dimensional electrophoresis, were identified by immunoblotting with CK-specific monoclonal antibodies. CK polypeptides 5, 7, 8, 15, 18 and 19 were identified in fresh normal and hyperplastic prostate. Expression of CK 15 has not been previously reported in human prostate. Analysis of central and peripheral zone tissues from human prostate did not reveal qualitative differences in CK expression between these areas. Epithelial cells harvested from fresh BPH tissue by percoll gradient centrifugation and propagated in vitro using selective culture techniques showed alterations in CK expression compared to intact human prostate. Specifically, CKs 6, 14, 16 and 17 were noted in cultured BPH epithelial cells but not fresh normal prostate or BPH tissue. Immunoblot analysis of the established prostate cancer cell lines PC3, DU145 and LNCAP showed expression of CKs 8 and 18 but not CKs 5, 7 and 15 which were observed in benign prostate. These studies further characterize CK expression in benign and malignant human prostate and provide insights which may be useful in differentiating normal, hyperplastic and malignant epithelial cells in the human prostate gland.  相似文献   
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31P, 1H and lactate spectroscopic imaging was used to evaluate the effects of hypothermia on focal cerebral ischemia produced by middle cerebral artery occlusion. The effects on high energy phosphate metabolism, pH, lactate and NAA were investigated in 24 spontaneously hypertensive rats subjected to either permanent or transient ischemia. Under either normothermic (37.5°C) or hypothermic (32°C) conditions, with permanent 6-h occlusion, there was little difference between groups in either the NMR measurements or the volume of infarction. In animals that underwent 3 h of ischemia followed by 12 h of reperfusion, the ischemic changes in lactate, pH, NAA, and high-energy phosphate returned toward control values, and there was a protective effect of hypothermia (infarct volume of 211 ± 26 and 40 ± 14 mm3 in normothermic and hypothermic groups, respectively). Thus, hypothermia did not ameliorate the changes in lactate, pH, NAA, or high energy phosphate levels occurring during ischemia, however, during reperfusion there was an improvement in both the recovery of these metabolites and pathological outcome in hypothermic compared with normothermic animals.  相似文献   
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This case report describes the simultaneous occurrence of autoimmune thrombocytopenia and the lupus anticoagulant in a patient with primary adenocarcinoma of the bronchus. Treatment with corticosteroids and plasmapheresis resulted in a return to normal of the partial thromboplastin time and the disappearance of the platelet antibodies. The carcinoma was inoperable.  相似文献   
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In an open label study, we analyzed the efficacy of botulinum toxin injection at the lower limbs of patients with hereditary spastic paraparesis (HSP). Fifteen patients who showed disabling spasticity with no or poor effect of oral treatment were recruited consecutively. Botulinum toxin was injected (400 U; Botox®) into the spastic muscles identified by clinical examination (equinus, varus, and pathological hip adduction). Patients were regularly assessed from the first day to the fifth month: spasticity (Ashworth), motor strength, range of movements, Functional Ambulation Categories (FAC), gait parameter, Rivermead Motor Assessment, self-analysis of benefit and satisfaction. We observed a moderate and significant ( P  < 0.05) reduction of ankle plantar flexor and hip adductor spasticity, with a partial increase in the range of the active and passive motion at the ankle and in gait velocity. At an individual level, six of 15 patients showed an increase in gait velocity. The FAC and RMA did not change. Patients often reported partial improvement in foot position and lower limb propulsion, and fair satisfaction. In conclusion, botulinum toxin injection can be effective in HSP patients with relatively ancient spasticity. This technique can be introduced into the therapeutic panel, which also includes physiotherapy, oral treatment and baclofen pump.  相似文献   
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