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1.
Congenital absence of the portal vein (CAPV) is a rare malformation of the splanchnic venous system. Although CAPV is usually detected in the pediatric age group, our patient was a 35-year-old woman. She had been diagnosed with CAPV in 1996 when she was 27 years old. In 1998, she was placed on hemodialysis due to chronic renal failure. After several episodes of encephalopathy in 2002, liver transplantation (LT) was recommended to her and her family. Since there was no suitable living donor candidate, she was put on the waiting list for a deceased donor liver transplant in Japan. In 2004, her ammonia level increased to around 300 microg/dl, and she went into a coma lasting for three days. After recovering from this event, she underwent a living domino transplantation using a whole liver donated by a familial amyloid polyneuropathy (FAP) patient. Her portal vein, which had drained directly into the inferior vena cava (IVC), was transected together with a cuff of the IVC wall and anastomosed to the graft liver portal vein in an end-to-end fashion. In conclusion, liver transplantation proved to be a safe and effective way to save this patient and improve her quality of life.  相似文献   
2.
The usefulness of carcinoembryonic antigen (CEA) as an indicator for recurrence and a guide to the treatment was evaluated from a retrospective analysis of 88 patients with recurrent gastric cancer. Sixty-two of these patients (70.5 per cent), 25 of whom had a preoperative positive assay, and 37 a negative assay, had elevated levels of CEA after disease progression. Averaged CEA level in patients with liver metastasis was significantly higher (872 ng/ml) than in those with peritoneal metastasis (68 ng/ml), with lymph node metastasis (103 ng/ml) or with local metastasis (93 ng/ml) (p<0.01). An elevation of CEA was found prior to the clinical manifestation of recurrence, and the average lead time was 4 months. In 25 patients with a lead time of more than 4 months, survival time after CEA elevation was 13.3 months, which was longer than the 6.5 months of 28 patients with less than 4 months. Thirty-seven of the 88 patients were treated after recurrence. The average survival period after the detection of recurrence was 9.4 months in patients with surgical treatments followed by chemotherapy, 5.9 months in those with chemotherapy alone and 3.8 months in those with surgery alone. The average survival period of 26 patients with positive CEA assays in recurrence was 5.1 months longer than of patients with negative assays. This fact suggested that early detection of recurrence followed by various treatments, in the elevated CEA group, contributes to favorable results.  相似文献   
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4.
It is widely known that IL-4 and IL-13 act on various kinds of cells, including B cells, resulting in enhancement of proliferation, class switching to IgE and expression of several surface proteins. These functions are important for the recognition of the various antigens in B cells and are known to be involved in the pathogenesis of allergic diseases. However, it has not been known whether IL-4/IL-13 is involved in the metabolism of various kinds of xenobiotics including 2,3,7,8-tetra-chlorodibenzo-p-dioxin (TCDD), and it remains undetermined whether TCDD, an environmental pollutant, influences IgE production in B cells, exaggerating allergic reactions. We identified IL-4- or IL-13-inducible genes in a human Burkitt lymphoma cell line, DND-39, using microarray technology, in which the AHR gene was included. The AHR gene product, the aryl hydrocarbon receptor (AhR), was induced by IL-4 in both mouse and human B cells in a STAT6-dependent manner. IL-4 alone had the ability to translocate the induced AhR to the nuclei. TCDD, a ligand for AhR, rapidly degraded the induced AhR by the proteasomal pathway, although IL-4-activated AhR sustained its expression. AhR activated by IL-4 caused expression of a xenobiotic-metabolizing gene, CYP1A1, and TCDD synergistically acted on the induction of this gene by IL-4. However, the induction of AhR had no effect on IgE synthesis or CD23 expression. These results indicate that the metabolism of xenobiotics would be a novel biological function of IL-4 and IL-13 in B cells, whereas TCDD is not involved in IgE synthesis in B cells.  相似文献   
5.
Several multiple, large-scale, genetic studies on autoimmune-disease-associated SNPs have been reported recently: peptidylarginine deiminase type 4 (PADI4) in rheumatoid arthritis (RA); solute carrier family 22 members 4 and 5 (SLC22A4 and 5) in RA and Crohns disease (CD); programmed cell death 1 (PDCD1) in systemic lupus erythematosus (SLE), type 1 diabetes mellitus (T1D), and RA; and protein tyrosine phosphatase nonreceptor type 22 (PTPN22) in T1D, RA, and SLE. Because these reports on association were not always evaluated in multiple ethnic groups and because ethnic difference in allele frequency of the variants has been also reported, we investigated allele frequencies of nine SNPs in four autoimmune-disease-associated loci in Caucasian, African-descent, and Japanese populations. Although SNPs in PADI4 had similar allele frequency among three groups [maximal difference 11%; (P >0.05)], the other three loci revealed statistically significant allele frequency differences (maximal difference 39% (P <0.00001), 13% (P <0.00001), and 8% (P <0.00001) in SLC22A4, PDCD1, and PTPN22, respectively). Of note, three SNPs in the three loci that had allele frequency more than 8% in the Caucasian population were either not polymorphic at all or extremely rare in the Japanese population. Our data suggest that ethnic variations of polymorphisms should be evaluated in detail, and differences should be incorporated into investigations of susceptibility variants for common diseases.  相似文献   
6.
 Vascular endothelial growth factor (VEGF), a potent angiogenic and vascular permeability factor, may be important as a mediator of brain tumour progression. However, it is still not clear whether VEGF plays a causative role in the early stage of glioma development. We investigated the relationship between VEGF protein expression (as assayed by immunohistochemistry) and different morphological parameters reflecting tumour progression (tumour diameter, vascular density and vascular diameter) in tumours at various stages. As a tumour model, ethylnitrosourea (ENU)-induced rat malignant astrocytoma was used. Tumours were classified by size and level of vascularity estimated by the von Willebrand factor (vWF) staining. Tumours less than 10 mm in diameter were designated early stage neoplastic lesions. All 34 early astroglial tumours were found to be VEGF positive. Increase in the VEGF immunopositive rate of tumour cells correlated significantly with increase in vascular density and vascular diameter. We suggest that VEGF induces angiogenesis and growth of microvessels, promoting growth of the early stage malignant astrocytoma. Received: 7 October 1997 / Accepted: 9 June 1998  相似文献   
7.
Osteosarcoma is one of the neoplasms that may occur following exposure to radiation. A case of osteosarcoma arising in the craniofacial bone with a short latency period of 3 years after radiotherapy for maxillary squamous cell carcinoma is described. A 64-year-old-man underwent right partial maxillectomy and chemoradiotherapy due to squamous cell carcinoma of his right maxillary sinus. Histologically, the tumor was composed of moderately differentiated squamous cell carcinoma with a component of spindle cell carcinoma. Three years later, osteosarcoma developed in the craniofacial bone within the irradiation field of the first tumor. Detailed histological examination demonstrated that there was no component of osteosarcoma in the first tumor or squamous cell carcinoma in the second tumor. Radiation-induced osteosarcoma usually occurs after a long latency period of more than 10 years after the radiotherapy. In this case, osteosarcoma was possibly a radiation-induced osteosarcoma with a short latency period of 3 years.  相似文献   
8.
1. To investigate postsynaptic potentials (PSPs), we made intracellular recordings from neurons of the amygdaloid central nucleus in slices from the guinea pig and rat brains maintained in vitro. The results from guinea pigs and rats were very similar. 2. In the presence of bicuculline (20 microM), focal electrical stimulation of the amygdaloid basal nucleus with low intensities elicited short-latency excitatory PSPs (EPSPs) followed by long-latency EPSPs. The short-latency EPSP was selectively blocked by 6-cyano-7-nitroquinoxaline-2,3-dion (CNQX; 10-20 microM). The long-latency EPSP was preferentially abolished by D,L-2-amino-5-phosphonovaleric acid (D,L-APV; 40 microM) and was augmented by removal of extracellular Mg2+. The compound EPSP reversed at -4 mV, which was close to -1 mV, the reversal potential for pressure-ejected glutamate (Glu). 3. When the intensity of the focal stimulation was increased in the presence of bicuculline (20 microM), CNQX (20 microM), and D,L-APV (50 microM), a second EPSP with a short latency and a prolonged duration could be evoked in approximately 65% of the neurons. The EPSPs were reversibly blocked by d-tubocurarine (50 microM) or hexamethonium (200 microM) but were unaffected by atropine (1 microM) or a 5-hydroxytryptamine type 3 receptor antagonist, ICS-205930 (5-10 microM). In these neurons, acetylcholine (ACh; 1-3 mM) caused a depolarization, associated with a decreased input resistance. 4. In the presence of CNQX (20 microM) and D,L-APV (50 microM), single focal stimulation of the dorsolateral subdivision in the central nucleus with low intensities elicited a depolarizing inhibitory PSP (IPSP). The IPSP was reversibly abolished by bicuculline (20-40 microM). The reversal potential (-63 mV) for the IPSP was similar to the reversal potential (-61 mV) for the response to gamma-aminobutyric acid (GABA) applied by pressure ejection. 5. In the presence of bicuculline (20-40 microM) and CNQX (20 microM), a repetitive focal stimulus with high intensities delivered to the dorsolateral subdivision produced a hyperpolarizing PSP followed by a slow depolarization in most neurons. Of putative inhibitory amino acid transmitters, glycine (Gly; 3 mM) produced only a hyperpolarization, associated with a decrease in input resistance. Strychnine (1-2 microM) reversibly blocked both the Gly hyperpolarization and the synaptically evoked hyperpolarization. The reversal potential of -81 mV for the hyperpolarizing PSP was close to -82 mV for the Gly hyperpolarization. The reversal potential for the Gly response was shifted to less negative values by increasing the external K+ concentration or decreasing the extracellular Cl- concentration.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
9.
The Thy-1 antigens or rat brain and thymus have been isolated and chemically characterized, but those of mice have not been identified. Moreover, it is uncertain whether the antigens are glycolipids or glycoproteins. This study with highly purified preparations of gangliosides GM1, 1GD1a, GD1b and GT1b from bovine brain and several ganglioside fractions from mouse brain showed that Thy-1 activity does not reside in gangliosides, but rather in the chloroform-methanol-insoluble residue of brain remaining after extraction of gangliosides. The antigen could be solubilized from this residue with a non-ionic detergent. The antigenic activity of the solubilized preparation was heat-labile but resistant to periodate. The chemical properties of the Thy-1 antigen of mouse brain are discussed.  相似文献   
10.
The experimentally induced cryptorchid mouse model is useful for elucidating the in vivo molecular mechanism of germ cell apoptosis. Apoptosis, in general, is thought to be partly regulated by the ubiquitin-proteasome system. Here, we analyzed the function of two closely related members of the ubiquitin C-terminal hydrolase (UCH) family in testicular germ cell apoptosis experimentally induced by cryptorchidism. The two enzymes, UCH-L1 and UCH-L3, deubiquitinate ubiquitin-protein conjugates and control the cellular balance of ubiquitin. The testes of gracile axonal dystrophy (gad) mice, which lack UCH-L1, were resistant to cryptorchid stress-related injury and had reduced ubiquitin levels. The level of both anti-apoptotic (Bcl-2 family and XIAP) and prosurvival (pCREB and BDNF) proteins was significantly higher in gad mice after cryptorchid stress. In contrast, Uchl3 knockout mice showed profound testicular atrophy and apoptotic germ cell loss after cryptorchid injury. Ubiquitin level was not significantly different between wild-type and Uchl3 knockout mice, whereas the levels of Nedd8 and the apoptotic proteins p53, Bax, and caspase3 were elevated in Uchl3 knockout mice. These results demonstrate that UCH-L1 and UCH-L3 function differentially to regulate the cellular levels of anti-apoptotic, prosurvival, and apoptotic proteins during testicular germ cell apoptosis.  相似文献   
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