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21.
Liver transplantation, which serves as treatment of familial amyloidotic polyneuropathy (FAP), and domino liver transplantation, which utilizes resected livers from patients with FAP for treatment of liver diseases, may induce changes in transthyretin (TTR), a pathogenic FAP-related protein. To evaluate this possibility, we performed a 70% hepatectomy or administered tacrolimus to Dark Agouti (DA) rats for 7 days and then measured changes in liver TTR mRNA levels and changes in serum TTR concentrations. After hepatectomy, TTR mRNA levels decreased by 77%; at day 3, they returned to preoperative levels. Except for slightly elevated serum TTR concentrations 12 h after operation, serum TTR levels remained unchanged. Thus, partial hepatectomy did not influence serum TTR concentrations. After tacrolimus administration, TTR mRNA declined by 56% 12 h after the experiment started; however, after day 3, a rebound phenomenon occurred until day 7. Tacrolimus may facilitate serum TTR degradation, although production of TTR in the liver also increased. This finding -- that TTR, the source of FAP-inducing amyloid, did not increase after transplantation -- may help post-transplantation treatment of patients who have FAP and other liver diseases.  相似文献   
22.
A 57-year-old man with a history of renal cell carcinoma presented with presyncope. He underwent nephrectomy years earlier followed by HLA-matched allogeneic peripheral-blood stem-cell transplantation. Echocardiographic investigation revealed a solitary right ventricle mass without contiguous vena caval or right atrial involvement. The mass was pathologically confirmed to be metastatic carcinoma in the right ventricular cavity. This case highlights the need to consider an underlying neoplastic syndrome in patients presenting isolated right ventricle mass by echocardiography.  相似文献   
23.
Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT.  相似文献   
24.
A 66-year-old right-handed man developed pure anarthria following pure word deafness. In addition to language disorders, his behavior gradually changed and finally included violence against his wife. Brain magnetic resonance imagings revealed atrophy of the left perisylvian area, which included the inferior half of the precentral gyrus and the upper portion of the superior temporal gyrus, consistent with frontotemporal dementia (FTD). It has been documented as either a disorder of expressive language or as an impaired understanding of word meaning. Unlike with pure anarthria, pure word deafness is not included in the clinical diagnostic current criteria for FTD. However, a large variety of language symptoms can appear in FTD according to the distribution of pathological changes in the frontotemporal cortices. This case suggests that pure word deafness could be a prodomal symptom of FTD.  相似文献   
25.
A 68‐year‐old man, who had no remarkable past medical history, was referred to a hospital because of disorientation and right‐sided hemiparesis. On magnetic resonance imaging, a contrast‐enhanced tumor in the left frontal lobe with perifocal edema was noted. He underwent left frontal lobectomy. Microscopic examination revealed infiltrative atypical astrocytes showing increased cellularity, distinct nuclear atypia, and many mitotic figures, while microvascular proliferation and necrosis were absent. Thus, the tumor was histologically diagnosed as anaplastic astrocytoma. It was of note that cytoplasmic eosinophilic granules were observed in approximately 25% of neoplastic cells. The granules were positively immunostained with anti‐αB‐crystallin antibody, and the other histochemical and immunohistochemical results also corresponded to Rosenthal fibers. The MIB‐1 labeling index of the highest area of the tumor was 22%, while that of granular cells was 2.1%. An ultrastructural study revealed amorphous electron‐dense structures attached to intermediate filament bundles, compatible with Rosenthal fibers. Such structures are relatively common in oligodendroglial tumors; however, they are extremely rare in astrocytic tumors. Fluorescence in situ hybridization targeted against chromosome 1 failed to demonstrate allelic loss of the short arm. The present case should also be discriminated from granular cell astrocytoma. We review related literature and discuss the significance of granules in gliomas.  相似文献   
26.
Langerhans cell histiocytosis is currently regarded as a reactive proliferative process of Langerhans cells rather than a malignancy. The disease is characterized by Langerhans cell infiltration of skin, lung, bone and other organs. We report a 74-year-old man with Langerhans cell histiocytosis who had generalized hemorrhagic and crusted papules. He also had diabetes insipidus. Because he did not have any severe constitutional symptoms or failure of vital organs, we applied topical PUVA treatment to his skin lesions, which responded well to the therapy. Diabetes insipidus, however, remained, in spite of X ray radiotherapy for the pituiary lesion.  相似文献   
27.
We measured the serum levels of manganese-superoxide dismutase (Mn-SOD) in acute myeloid leukemia (AML) and acute lymphoid leukemia (ALL). Serum Mn-SOD level for normal subjects was 94.1 +/- 23.5 ng/ml (mean +/- S.D.), the levels for AML and ALL patients were 159.6 +/- 77.1 ng/ml and 154.4 +/- 77.0 ng/ml, respectively. The serum Mn-SOD levels were unrelated to individual intracellular Mn-SOD levels, but correlated well with serum lactate dehydrogenase values. Regression of the leukemia was accompanied by decrease in the serum level of Mn-SOD. Serum Mn-SOD may thus serve as a measure of the activity of the disease.  相似文献   
28.
The study examines the osteoinductive potential of recombinant human morphogenetic protein 2 (rhBMP-2) radiologically and histologically in rat calf muscle.Ten male Wistar rats were used. rhBMP-2 50 μg was implanted with atelopeptide type I collagen as carrier in a pouch in rat calf muscle (n=5), and atelopeptide type I collagen alone was implanted in a further five as control. Induction of osteogenesis at 4 weeks was investigated.In all rats in which rhBMP-2 had been implanted there was a radio-opaque shadow in the muscle in the soft tissue radiograph. No such shadows were noted in the control group. Histological examination showed bony trabeculum, osteoblasts, and vigorous bone marrow including fatty marrow and angioid tissue both at the margins and in the center of the excised lumps in the rhBMP-2 group. There were no such signs in the control group.rhBMP-2 may be capable not only of inducing the formation of bone, but also of inducing a ‘self-supporting bone organ’ in the muscle.  相似文献   
29.
The alteration of the blood flow of the proper hepatic artery (PHA) on occlusion of the common hepatic artery (CHA) was studied intraoperatively using an electromagnetic flowmeter for 18 cases of malignant gastric tumor. PHA blood flow was 280 +/- 225 ml/min before CHA occlusion, and after the occlusion it was 170 +/- 132 ml/min, or 64 +/- 15% of the pre-occlusion flow (n = 16). The pulsation of PHA after CHA occlusion was palpable in all cases, and there were no complications due to ischemia in 17 cases which underwent Appleby's operation. These results suggested that there was fairly good blood flow in PHA maintained by collaterals after CHA occlusion and that, clear pulsation of PHA could be regarded as evidence of sufficient blood flow. Tissue blood flow (TBF) measurement for the liver and gall-bladder by H2 gas clearance method was also done in several cases of Appleby's operation and of other abdominal operations. TBF of the gallbladder was significantly lower in cases of Appleby's operation on the day of operation (p less than 0.02), but the difference between the two operation groups was not recognized 5 days after surgery, suggesting rather quick recovery of circulation. As to hepatic TBF, significant decrease following Appleby's operation could not be proved.  相似文献   
30.
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