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41.
BACKGROUND: Hepatic artery thrombosis (HAT) remains an important cause of graft loss after liver transplantation. Emergency rearterialization methods are limited in cases of living-related liver transplantation in which the graft hepatic artery is thin and short. CASE: A 19-year-old woman who underwent living-related liver transplantation for biliary atresia developed HAT on the 4th postoperative day. During the emergency laparotomy the recipient hepatic artery was found to be too short to anastomose, so the recipient's right gastroepiploic artery was anastomosed to the graft hepatic artery. The patient is now alive and well 6 months after reoperation, and she has experienced no further episode of HAT. CONCLUSION: The right gastroepiploic artery can be used easily and safely for hepatic graft revascularization without causing ischemia of the stomach. An additional skin incision is not required, and the artery is long enough to anastomose to the graft artery directly. The method of hepatic graft rearterialization described here is an important option for patients who undergo living-related or split liver transplantation.  相似文献   
42.
Effects of transforming growth factor beta-1 (TGF-beta1) and all-trans-retinoic acid (All-trans-RA) on development of bulbourethral glands (BUGs) of neonatal mice were investigated in vitro. BUGs from 0-day-old male mice were cultured for 6 days in serum-free, chemically defined medium containing transferrin and bovine serum albumin, supplemented with 5alpha-dihydrotestosterone (DHT; 10-8 M) and insulin (10 microg/mL) alone or in combination. Prior to culture, BUGs from 0-day-old mice consisted of a simple epithelial rudiment encapsulated by mesenchyme. Epithelial growth and ductal branching occurred in BUGs cultured in medium containing DHT and insulin or DHT alone, but epithelial branching did not occur in BUGs cultured in the presence of insulin alone. Addition of TGF-beta1 at concentrations of > 5 ng/mL (0.2 x 10-9 M) to medium containing both insulin and DHT, inhibited the expected increase in overall size of BUGs, epithelial area and ductal branching in a dose-dependent manner. TGF-beta1 also decreased [3H]-thymidine labelling indices of both epithelium and mesenchyme. TGF-beta1 at 10 ng/mL elicited these inhibitory effects on BUGs cultured in medium containing DHT alone. Addition of All-trans-RA (10-8 to 10-6 M) to the medium containing DHT plus insulin, or DHT alone did not exert significant effects on either overall size of BUGs or epithelial growth and ductal branching. All-trans-RA at 10-6 M decreased the [3H]-thymidine labelling index of mesenchyme of BUGs cultured in medium with DHT plus insulin or DHT alone, but did not decrease the [3H]-thymidine labelling index of epithelium. The present results indicate that TGF-beta1 inhibits androgen-induced epithelial and mesenchymal growth as well as epithelial morphogenesis of BUGs from neonatal mice. Such an inhibitory effect of TGF-beta1 is not mimicked by All-trans-RA at physiological concentrations.  相似文献   
43.
Activated STAT1 suppresses proliferation of cultured rat mesangial cells   总被引:2,自引:0,他引:2  
BACKGROUND: JAK-STAT signaling has been shown to promote development and proliferation in lymphopoietic and hematopoietic lineages. We investigated the effect of activated STAT1 on mesangial cell proliferation. METHODS: Rat mesangial cells of primary culture (rMCs) were used in the following experiments: (1) Whole cell lysates were immunoblotted against JAK1 and JAK2. (2) Whole cell lysates and nuclear proteins were extracted from rMCs with or without treatment with interferon-gamma, and immunoblotting was performed against both STAT1 and tyrosine (701)-phosphorylated STAT1. (3) rMCs and rMCs electroporated with either wild-type STAT1, mutated STAT1, or antibody against STAT1 were incubated with interferon-gamma for 20 hours, followed by a further incubation with [3H]-thymidine for four hours. RESULTS: JAK1, JAK2, and STAT1 were detected in whole cell lysates, suggesting that JAK-STAT signaling could be activated by interferon-gamma (INF-gamma). Using an antibody specific for tyrosine-phosphorylated STAT1, we detected signal in the INF-gamma-treated nuclear extracts, which showed translocation of phosphorylated STAT1 to the nucleus. [3H]-thymidine incorporation in the presence of INF-gamma was significantly lower than that of control in a dose-dependent manner. The introduction of wild-type STAT1 enhanced the effect of interferon-gamma and decreased [3H]-thymidine incorporation, whereas tyrosine-mutated (Y701F) STAT1 and SH2 domain (R602T)-mutated STAT1 reversed INF-gamma-induced suppression of [3H]-thymidine incorporation. Electroinjected antibody against STAT1 increased [3H]-thymidine incorporation upon stimulation with INF-gamma. CONCLUSION: STAT1 activated by interferon-gamma suppresses mesangial cell proliferation.  相似文献   
44.
Gene amplification is a relatively frequent event in human malignant tumors and is believed to play an important role in tumor progression. The int-2 and erbB genes are amplified more frequently than any other genes in human esophageal cancer. In order to investigate the correlation between these two proto-oncogenes and the clinical behavior of esophageal cancer, we examined DNA amplification of int-2 and erbB and analyzed their relationship to clinicopathological variables. Genomic DNA was extracted from 21 esophageal squamous carcinomas and normal esopfiageal mucosa, as well as from 4 metastatic tumors. We used Southern blot analysis for detection of gene amplification. Amplification of int-2 was observed in 13 of 21 cases (62%) and in all the metastatic tumors (4/4; 100%). We found a significant correlation between amplification of int-2 and the length of the primary lesion. Amplification of erbB was detected in 3 of 18 patients (17%). All patients who showed amplification of erbB also demonstrated amplification of int-2. These results suggest that amplification of int-2 or neighboring genes on 11q may participate in tumor progression and metastasis in patients with esophageal squamous cancer.  相似文献   
45.
We identified novel 10 multi-cysteine peptides, namely Magi 7-16, from the spider Macrothele gigas by simple random cDNA screening of the venom gland. Mass analysis of the crude venom detected the mass numbers of the cross-linked forms of all peptides, confirming their presence in the venom. Magi 11, a C-terminus amidated peptide, was chemically synthesized and was indistinguishable from the native peptide proving the feasibility of the method for peptide identification. Moreover, toxicological assays showed diverse lethal or paralytic activities of these peptide toxins on mice and/or insects.  相似文献   
46.

Purpose

Sorafenib is primarily metabolized in the liver, by CYP3A4-mediated oxidation and UGT1A9-mediated glucuronidation. However, there is little information about the pharmacokinetic interaction of sorafenib. Here, we report a pharmacokinetic interaction between sorafenib and the CYP3A4 inducer prednisolone in a patient with hepatocellular carcinoma (HCC).

Patients and methods

The patient was a 72-year-old woman diagnosed with HCC. She was treated with sorafenib at 400 mg daily. On day 9, sorafenib was discontinued due to drug eruption. Nine months later, she was rechallenged with sorafenib at 400 mg daily concurrently with oral prednisolone. Prednisolone was started at 20 mg daily and was tapered by 5 mg every 14 days. We assessed the pharmacokinetics of sorafenib and its major metabolite M-2.

Results

The concentration of sorafenib was gradually increased following tapering of prednisolone. On day 56 after rechallenge, she developed G3 oral mucositis. At this time, serum trough concentrations of sorafenib and M-2 were at 5.9 and 1.1 μg/ml, respectively. Consequently, sorafenib dosage was reduced to 200 mg daily, and the oral mucositis was attenuated. The subsequent concentrations of sorafenib and M-2 obtained with a dose of 200 mg daily ranged from 1 to 3 μg/ml and from 0.1 to 0.4 μg/ml, respectively. Computed tomography scan showed a complete response of the liver tumor with no further recurrence of the rash.

Conclusions

We have demonstrated for the first time that prednisolone stimulates the sorafenib metabolism and that therapeutic drug monitoring could be useful during sorafenib therapy.  相似文献   
47.
The accumulation of cisplatin is decreased in many cisplatin-resistant cell lines, and an active efflux pump for cisplatin exists in some of them, but it has not yet been identified. In this study, we transfected the copper-transporting P-type ATPase cDNA (ATP7B) into human epidermoid carcinoma KB-3-1 cells. The transfectant, KB/WD cell line, which overexpressed the P-type ATPase, ATP7B, was resistant to both cisplatin (8.9-fold) and copper (2.0-fold). The accumulation of cisplatin in KB/WD cells was lower than in mock-transfected KB/CV cells, and the efflux of cisplatin from KB/WD cells was enhanced compared with KB/CV cells. KB/WD cells were sensitive to other heavy metals, such as antimony, arsenate, arsenite, cadmium, and cobalt. ATP7B was overexpressed in cisplatin-resistant prostate carcinoma PC-5 cells but not in the parental PC-3 cells and the revertant PC-5R cells. ATP7B may be involved in cisplatin resistance in some tumors.  相似文献   
48.
Ovarian cancer is influenced by exogenous and endogenous estrogens as suggested by experimental and epidemiological evidence. Estrogen receptor beta is a predominant estrogen receptor in the normal ovary. Polymorphisms in the estrogen receptor beta gene (ESR2) might influence epithelial ovarian risk through regulation of cell proliferation and apoptosis. This population-based case–control study included 313 women with epithelial ovarian carcinoma and 574 controls, frequency-matched on age and ethnicity. Unconditional logistic regression was used to test associations of rs1271572, rs1256030, rs1256031, and rs3020450 ESR2 genotypes with ovarian cancer risk. Compared to homozygous common allele carriers, homozygous carriers of variant alleles for rs1271572 [odds ratio (OR) = 1.79, 95% confidence interval (CI):1.15–2.79, p global = 0.01] and rs1256030 [OR = 1.67, CI: 1.08–2.59, p global = 0.04], and women with haplotypes, including variant alleles of rs1271572, rs1256030, and rs1256031 SNPs [OR = 1.75, CI: 1.17–2.63, p global = 0.007], had significantly increased risk of ovarian carcinoma. The association of the rs1271572 genotype was strongest among women who had never used contraceptive steroids (p for interaction = 0.04). Our data suggest that ESR2 might be a susceptibility marker for epithelial ovarian cancer.  相似文献   
49.
OBJECT: The effects of percutaneous transluminal angioplasty (PTA) and stent placement for stenosis of the petrous or cavernous portion of the internal carotid artery (ICA) were compared. METHODS: Twenty-four patients with symptomatic, greater than 60% stenosis of the petrous or cavernous portion of the ICA were treated using PTA or stent placement; 15 were treated with PTA and nine with stent insertion. Initial and follow-up results (> 3 months posttreatment) were compared in each group. Stenotic portions of the ICA were successfully opened in 13 of 15 patients in the PTA group, and in all nine patients in the stent-treated group. In one case in the PTA group stent delivery was attempted; however, the device could not pass through the vessel's tortuous curve, and PTA alone was performed in this case. Postoperatively, the mean stenotic ratio decreased from 72.1 to 29.6% in the PTA group, and from 75.6 to 2.2% in the stent-treated group. In four patients in the PTA group, stenoses greater than 50% were demonstrated on follow-up angiography performed at 3 to 6 months after PTA. In the stent-treated group, no restenosis was encountered, although in one case acute occlusion of the stent occurred; the device was recanalized with PTA and infusion of tissue plasminogen activator. This case was the only one of the 24 in which any neurological deficits related to the endovascular procedure occurred. Stent placement brought a greater gain in diameter than did PTA at the initial and late follow-up period; this gain was statistically significant. CONCLUSIONS: Stent placement is more effective than PTA for stenosis of the petrous or cavernous portion of the ICA from the viewpoint of initial and late gain in diameter.  相似文献   
50.
Lumbar hernias are extremely rare. The posterolateral abdominal wall has two susceptible areas - the superior (Grynfeltt-Lesshaft''s triangle) and the inferior (Petit''s triangle) lumbar triangles - that cause superior and inferior lumbar hernias, respectively. We herein report a 67-year-old woman with nephrotic-range proteinuria caused by primary superior lumbar hernia. Superior lumbar hernias should be considered as a differential disease causing massive orthostatic proteinuria in adults. The present case highlights the importance of considering lumbar hernia in patients with flank swelling and the potential complications that may result from a missed diagnosis.  相似文献   
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