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Spontaneous rupture of the liver has been described in association with many benign and malignant conditions. We report, to our knowledge, the first case of spontaneous rupture of the liver upon revascularization, requiring total hepatectomy and portocaval shunt, followed by successful retransplantation. Routine pathological examination of the explanted liver failed to reveal the etiology of the rupture. However, electron microscopy demonstrated abnormal collagen in the hepatic arterial wall compatible with a collagen disorder such as Ehlers-Danlos type IV disease. We conclude that the donor liver had a previously undiagnosed collagen disorder. Review of the literature does not preclude the use of livers from donors with a history of connective tissue disorders. Based on our experience one should exercise caution when using livers from such donors. With a history of connective tissue disorder in an immediate family member, further tests should be performed in the donor to rule out a subclinical connective tissue disorder. In addition, a review of all patients reported thus far to have undergone total hepatectomy and portocaval shunt, followed by liver transplantation as a two-stage procedure is presented.  相似文献   
68.
Infiltrating pleomorphic lobular carcinoma (PLC) is an aggressive variant of infiltrating lobular carcinoma. Recently, in situ changes identical to PLC (PLCIS) have been described. The role of prognostic markers and their correlation with therapeutics, clinical outcome, and genetic changes is not well established in PLC. The authors examined 38 cases of this entity to understand better this tumor's biology. Immunohistochemical (IHC) analysis was performed in 21 specimens for estrogen and progesterone steroid receptors, p53, Her 2 (p185), and GCDFP-15. Genomic deoxyribonucleic acid was obtained from microdissected tumor as well as normal control cells, and loss of heterozygosity was investigated at the ESR (16q24), p53 (TP53 17p), Her 2 (17q 11-12), and BRCA 1 (17q12-25) loci. In this series, the average patient age was 57.5 years (age range, 24-92 years). Twenty-seven women were postmenopausal. Tumor size ranged from 1.2 to 25 cm. Six patients were a pathologic stage I; 19, stage II; 12, stage III; and one, stage IV. Histologically, multifocal nodular aggregates of discohesive pleomorphic tumor cells were seen interspersed in dense and fibrotic breast parenchyma. Twenty-nine percent of the specimens demonstrated associated signet ring cells. The remainder had dishesive, globoid, plasmacytoid cells with high-grade nuclear features. PLCIS was identified in 17 of 38 patients (45%), and lobular carcinoma in situ (LCIS) was noted in 8 patients (21%). IHC analysis showed estrogen immunoreactivity in 81%, progesterone in 67%, GCDFP-15 in 71%, and Her 2 in 81% (2+ to 3+ membranous staining) of specimens. Antibodies to p53 stained the tumor cell nuclei in 48% of the tumors. Loss of heterozygosity was identified in 52% of the specimens at the p53 locus, 18% at the ESR locus, 19% to 24% at the Her 2 loci, and 27% to 32% at the BRCA 1 locus. Follow-up was available in 19 patients and ranged from 12 months to 15 years (mean, 73 months). Seven patients had no evidence of disease at last examination (range, 1-15 years), three patients were alive with disease (range, 2-14 years), and nine patients were dead of disease (range, 2 months-9 years). Six patients had subsequent diagnoses of tumor in the contralateral breast. Analysis shows that PLC tends to appear in older postmenopausal women who present with locally advanced disease. PLCIS was found to be associated with PLC 45% of the time. The aggressive clinical course of patients with PLC is supported by tumor immunoreactivity with unfavorable markers Her 2 and p53. Overexpression of Her 2 in PLC may be therapeutically relevant, enabling the use of novel chemotherapeutic drugs like Herceptin. Interestingly, tumors that were Her 2 immunoreactive also maintained estrogen hormone immunoreactivity.  相似文献   
69.
Several studies indicate that increased intrarenal adenosine concentrations may attenuate puromycin-aminonucleoside (PAN)-induced nephropathy in rats. The purpose of this study was to investigate the chronic effects of caffeine, a nonselective adenosine receptor antagonist, on renal function and structure in PAN-induced nephropathy. Animals were randomized to receive drinking water or 0.1% caffeine solution. PAN was administered in two doses to a subset from each group at 1 week (100 mg/kg, s.c.; Purom-1) and 15 wks (80 mg/kg, s.c.; Purom-2) after initiating caffeine treatment (PAN and CAFF-PAN groups). The remaining animals served as time controls (CON and CAFF groups). Renal excretory function was followed for 23 wks. Caffeine consumption significantly augmented PAN-induced proteinuria after both PAN injections (Purom-1 and Purom-2, p<0.05 and p<0.001 respectively; CAFF-PAN vs. PAN). In addition, caffeine potentiated the transient reduction in creatinine clearance (CrCl) induced by PAN. Caffeine consumption for 23 wks significantly reduced CrCl in conscious nephrotic animals (4.76 +/- 0.98 vs. 8.51 +/- 1.55 L/kg/day, CAFF-PAN vs. PAN). Seven days after both PAN injections, increased plasma renin activity was detected in animals that were consuming caffeine as compared with corresponding control groups (CAFF and CAFF + PAN vs CON and PAN, respectively). Eight weeks after the second injection of PAN, acute measures of renal hemodynamic and excretory function were compared in anesthetized animals and renal samples were analyzed for histological changes. In PAN-rats, caffeine treatment for 23 weeks significantly reduced inulin clearance (0.28 +/- 0.09 vs. 0.57 +/- 0.12 mL/min/gr kidney. CAFF-PAN vs PAN, p<0.05), tended to increase renal vascular resistance (59.0 +/- 9.5 vs. 42.9 +/- 5.5 mmHg/mL/min/gr kidney, CAFF-PAN vs. PAN, p < 0.06), potentiated the development of more severe tubulointerstitial damage (tubular atrophy, presence of proteinaceous material, tubular dilatation, interstitial inflammation, interstitial fibrosis), and tended to increase glomerulosclerosis. In conclusion, this study indicates that caffeine adversely affects renal function in PAN-nephrotic rats, and that this effect may be due, in part, to increased activity of the renin angiotensin system.  相似文献   
70.
A shortage of kidney donors has contributed to the interest in laparoscopic live-donor nephrectomy. Three transperitoneal ports are used, as is an AESOP robot. To maintain urine flow, the donor is kept volume expanded during the procedure, and the pneumoperitoneum pressure is minimized. The most critical and hazardous part of the surgery is dissection of the renal artery and vein. Abundant periureteral tissue should be left to protect the blood supply. Harvest of the right kidney is more difficult. Placing the extraction incision in the right upper quadrant and using a Satinsky clamp instead of a stapling device at the origin of the renal vein will provide maximum venous length and help prevent postoperative thrombosis of the allograft. In the first 175 laparoscopic renal harvest procedures at Johns Hopkins, the complication rate was 14%, the rate of open conversion was 2%, and 3% of the patients required transfusions. These rates improved with experience. There was no significant difference in the performance of the allografts or the recovery of the recipients from what is seen after open kidney harvest. Wider acceptance of laparoscopic renal harvest will increase the number of donors and will be helped by development of methods and devices that shorten the learning curve.  相似文献   
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