伊東 昌広

Background - Reactive oxygen species (ROS) may mediate pressure overload - induced myocardial hypertrophy. NADPH oxidase may be involved in this process, because its expression and activity are upregulated by pressure overload and because myocardial hypertrophy caused by a subpressor infusion of angiotensin is attenuated in mice deficient in the gp91(phox) catalytic subunit of NADPH oxidase. Methods and Results - To test the role of NADPH oxidase - dependent ROS in mediating pressure overload - induced myocardial hypertrophy, we subjected transgenic mice lacking gp91phox to chronic pressure overload caused by constriction of the ascending aorta. Contrary to our hypothesis, neither myocardial hypertrophy nor NADPH-dependent superoxide generation was decreased in gp91(phox)-deficient mice after aortic constriction. Aortic constriction caused an exaggerated increase in p22(phox) and p47(phox) mRNA in gp91(phox)-deficient mice. Conclusions - These results indicate that gp91(phox) is not necessary for pressure overload - induced hypertrophy in the mouse and suggest the involvement of another source of ROS, possibly an NADPH oxidase that does not require the gp91(phox) subunit.

Postextrasystolic potentiation is the phenomenon in which ventricular contractile force is strengthened by a preceding premature beat. However, the response of diastolic function after an extrasystole is unknown. We studied 58 patients with chronic heart failure (CHF) and two control subjects to evaluate the response of relaxation following extrasystole. At cardiac catheterization, from the derivative of the left ventricular (LV) pressure, the ratio of LV peak negative dP/dt (-dP/dt) of a postextrasystole to a basal beat was calculated and defined as the postextrasystolic relaxation response (PRR). PRR was compared with parameters of left ventriculography: LV end-diastolic volume index (EDVI), LV end-systolic volume index (ESVI), and LV ejection fraction (EF). The PRRs of the two control subjects were 0.80 and 0.84. The mean PRR of the CHF patients was 0.99 +/- 0.15. In all subjects, including patients and controls, correlation analysis between ( EDVI, ESVI, and EF) and PRR yielded the following: (a) EDVI vs. PRR: R = 0.273, p = 0.036; (b) ESVI vs. PRR: R = 0.446, p < 0.001; and (c) EF vs. PRR: R = -0.520, p < 0.001. Thus, normal or non-failing human hearts showed a decline of -dP/dt in postextrasystole compared with the basal beats, but failing hearts had potentiated relaxation following an extrasystole.

In laboratory animals, intrasplenic hepatocyte transplantation corrects the physiologic abnormalities associated with decompensated liver disease. The clinical experience with hepatocyte transplantation for cirrhosis has been disappointing when compared with laboratory experience. The route of hepatocyte delivery may influence hepatocyte engraftment and function. Outbred pigs were recipients of allogeneic pig hepatocytes. Donor hepatocytes were isolated by collagenase perfusion and labeled using 5(6)-carboxyfluorescein diacetate succinimidyl-ester (CMFSE). Cells were introduced into pig spleens by infusion through the splenic artery or by direct splenic puncture. Direct intrasplenic injection produced engraftment that was far superior to that obtained using splenic artery infusion. Splenic artery infusion produced a gastric erosion and large areas of splenic necrosis secondary to vascular occlusion with hepatocytes, whereas direct splenic injection was associated with clinically insignificant intraabdominal hemorrhage. The route of hepatocyte delivery may influence hepatocyte engraftment and explain the disparity in efficacy of hepatocyte transplantation between the laboratory and clinic.

Background & Aims: Hepatocyte transplantation has been proposed as an alternative to liver transplantation for the treatment of hepatic failure. A major limitation to this form of therapy is the availability of human livers as a source of hepatocytes. The use of porcine hepatocytes might address this problem; however, xenogeneic hepatocytes are thought to be functionally incompatible across species and susceptible to irreversible rejection. Methods: Liver cirrhosis was induced with phenobarbital and carbon tetrachloride. Only rats with decompensated liver failure that did not correct 4 weeks after the discontinuation of carbon tetrachloride were subjected to intrasplenic rat or porcine hepatocyte transplantation. The immunologic integrity of cirrhotic rats was assessed by allogeneic skin grafting, and the immune response to transplanted porcine hepatocytes was assessed by enzyme-linked immunosorbent assay. Results: Porcine hepatocytes restored metabolic function and prolonged the survival of cirrhotic rats, as well as rat hepatocytes. Cirrhotic rats retained the ability to reject allogeneic skin grafts and showed an immune response to the engrafted hepatocytes. Despite this, survival of transplanted porcine hepatocytes was accepted in cirrhotic rats for a period of weeks without immunosuppression. Conventional immunosuppression with FK506 allowed successful retransplantation with hepatocytes from a second porcine donor. Conclusions: Hepatocytes transplanted between widely divergent species can function to correct liver failure in cirrhotic rats and prolong their survival. Conventional immunosuppression allows long-term functioning of xenogeneic hepatocyte retransplants and suggests that hepatocyte xenotransplantation might be useful as a bridge to liver transplantation and could potentially provide long-term hepatic support.

Parathyroid hormone-related peptide (PTHrP) induces pathological bone resorption in an endocrine manner, resulting in hypercalcemia of malignancy. However, the histopathological aspect of the action of PTHrP secreted by tumor cells on bone resorption has not well been documented. Therefore, we studied cell-cell interactions between bone cells, stromal cells, and PTHrP-secreting tumor cells (EC-GI-10) morphologically. Tumor cells injected subcutaneously into the parietal region formed a tumor mass, invading the bone marrow. The tumor mass was surrounded by a membrane structure consisting of stromal cells. These stromal cells were positive for alkaline phosphatase (ALPase). Tartrate-resistant acid phosphatase (TRAPase)-positive osteoclasts were localized close to the ALPase-positive cells, and numerous osteoclasts were observed on the neighboring bone surfaces. PTHrP, vascular endothelial growth factor (VEGF), and matrix metalloproteinase (MMP)-9 were detected in the tumor cells. Using RT-PCR, expression of interleukin (IL)-1alpha, IL-1beta, and PTHrP, which are strong bone resorption factors, was detected in the tumor cells. Some ALPase-positive cells localizing on the neighboring bone surfaces and endothelial cells revealed PTH/PTHrP receptor immunoreactivity. Ultrastructurally, numerous blood vessels were observed between the tumor nests and the stromal cells. The nests were surrounded by a basement membrane, but it was discontinuous, therefore permitting direct contact between the tumor cells and the stromal cells. These results indicate that PTHrP secreted by tumor cells appears to stimulate osteoclast differentiation and bone resorption in a paracrine manner through PTH/PTHrP receptor-immunopositive cells. IL-1alpha, IL-1beta, VEGF, and MMP-9 may also be involved in facilitating osteoclast formation and the subsequent bone resorption.

The shortage of organ donors has impeded the development of human hepatocyte transplantation. Immortalized hepatocytes could provide an unlimited supply of transplantable cells. To determine whether immortalized hepatocytes could provide global metabolic support in end-stage liver disease, 35 immortalized rat hepatocyte clones were developed by transduction with the gene encoding the simian virus 40 T antigen (SV40Tag). The SV40Tag sequence and a suicide gene, herpes simplex virus thymidine kinase (HSV-tk), were flanked by loxP sequences so that they could be excised by Cre/lox recombination. When transplanted into the spleens of portacaval-shunted rats, 3 of the 35 immortalized hepatocyte clones prevented the development of hyperammonemia-induced hepatic encephalopathy. The protection was reversed by treatment with ganciclovir, which kills HSV-tk-expressing cells. Transplantation of alginate-encapsulated, immortalized hepatocytes into the spleens of cirrhotic rats resulted in significant improvement in prothrombin time, serum albumin and bilirubin levels, hepatic encephalopathy score, and duration of survival. The metabolic support provided by the immortalized cells equaled that observed after transplantation of primary rat hepatocytes. In conclusion, immortalized hepatocytes can function as well as primary hepatocytes following transplantation and can be engineered to contain safeguards that could make them clinically useful. Further investigation is warranted regarding the mechanisms of loss of mass or function of the transplanted hepatocytes over time and how the relatively few engrafted hepatocytes can ameliorate liver decompensation in cirrhosis.

Patients with severe Ever diseases, such as Ever cirrhosis and biliary atresia, have low natural killer (NK) cell activity. The relations between INK activity and measures of Ever function, including serum levels of total bilirubin, total bile acids, bile acid components, aspartate aminotransferase, and alanine aminotransferase, and platelet count were examined in patients with biliary atresia (6 boys and 6 girls; mean age, 4.8 +/- 5.7 years) and patients with liver cirrhosis due to hepatitis C virus infection (10 men and 2 women; mean age, 54.3 +/- 13.8 years). Univariate analysis showed that platelet count was positively correlated with INK activity, in patients with bilary atresia (r = 0.611, P < 0.05). Serum levels of free chenodeoxycholic acid were negatively correlated with NK activity both in patients with biliary atresia (r = -0.647, P < 0.05) and in patients with hepatitis C virus-related liver cirrhosis (r = -0.876, P < 0.01). None of the other free bile acids or conjugated bile acids or other indicators of liver function were correlated with NK activity. Multiple stepwise regression analysis showed that only levels of free chenodeoxycholic acid were independently correlated with NK activity. All patients with biliary atresia underwent Ever transplantation from living related donors. NK activity had increased significantly two months after transplantation (from 24.1 ± 20.2% to 49.2 ± 12.5%, P < 0.01). In contrast, levels of free chenodeoxycholic acid in transplant recipients had decreased significantly two months after transplantation (from 1.22 +/- 1.16 to 0.26 +/- 0.21 mumol/l, P < 0.05). In conclusion, in patients with biliary atresia or liver cirrhosis, NK activity in peripheral blood decreases, mostly because of free chenodeoxycholic acid.

OBJECTIVES We investigated the efficacy of percutaneous coronary intervention (PCI) in patients with coronary spastic angina (CSA) and severe organic stenosis. BACKGROUND Coronary spasm occurs at the site of organic stenosis in most patients with CSA and severe stenosis, whereas multivessel spasm occurs frequently in those with normal coronary arteries. The incidence of multivessel spasm and the efficacy of PCI in patients with CSA and severe stenosis have not been fully elucidated. METHODS Forty-five patients with CSA and severe stenosis underwent spasm provocative testing with intracoronary acetylcholine before and 7 3 months after PCI (20 patients had angioplasty and 25 patients had stenting), when all patients were free of restenosis. RESULTS Spasm was induced at the site of severe stenosis in 30 patients (66.7%) with (n = 12) or without (n = 18) spasm induced in another vessel. In the remaining 15 patients, spasm was induced at a different site in the stenotic vessel and/or in another vessel. Repeat provocative tests were performed in 43 of 45 patients. Although spasm was never induced at exactly the same site of the initial stenosis that had been dilated, spasm was induced at a different site in the dilated vessel and/or in another vessel, in 33 (76.7%) of 43 patients. Multivessel spasm occurred in 28 (62.2%) of 45 patients on one or both provocations. CONCLUSIONS Spasm was frequently induced at a site different from the initial stenosis, even in the absence of restenosis after PCI. Calcium antagonists should be continued in most patients with CSA who show no restenosis after PCI. (C) 2002 by the American College of Cardiology Foundation.

標記術後患者15例に対して経皮的胃電図検査とアセトアミノフェン法検査を行い,胃運動能・排出能の術後回復過程を検討した.その結果,胃運動能は術後21日目に回復し,胃排出能は術後28日目に回復することが明らかになった

幽門輪温存膵頭十二指腸切除術(PpPD)を受けた2例と,胃切除を伴う膵頭十二指腸切除術を受けた4例の術後膵外分泌機能を便中キモトリプシンテスト(FCT)と,従来より行われているpancreatic function diagnostant testで検討した.その結果,いずれのtestにおいても膵外分泌機能はPpPD群の方が有意に良好であり,PpPDの再建術式別では,Billroth-II法に比べてBillroth-I法が良好であった.FCTは術後膵外分泌機能を評価する手段として簡便かつ有用な方法であると考えられた

47歳女.眼球黄染を主訴とした.血液生化学所見,US,CT,ERCP,PTBD,EUS所見等により,嚢胞性病変を伴う膵頭部癌と診断し,切除術を施行した.胃幽門部は,膵頭部の嚢胞の圧排により膨瘤しており,膵頭部の腫瘍は横行結腸間膜後面と上腸間膜静脈に浸潤していた為,膵頭十二指腸切除,門脈合併切除,2群リンパ切郭清を行った.膵頭部上方に認めた大きな嚢胞の大部分は乳頭腺腫で乳頭状隆起の部分は乳頭腺癌であった.乳頭状隆起の部分から膵実質内では管状腺癌となり,浸潤性に発育して総胆管,主膵管に浸潤していた.膵鉤部には小さい嚢胞があり,乳頭腺腫であった.管状癌と小さい嚢胞間では,小さい嚢胞の周囲へ管状腺癌の浸潤を認めた.これらにより膵頭部に発生した膵管内乳頭腫の一部が癌化し,乳頭腺癌から管状腺癌へと変化,浸潤性に発育していったと考えられた.症例は6ヵ月後に再発,癌死した

45歳男.胃X線検査では噴門部中央に潰瘍のある大きな腫瘤陰影が認められた.内視鏡検査では粘膜下腫瘍と診断され,潰瘍部分からの生検で平滑筋肉腫と診断された.CTでは腫瘤は胃壁外に発育していた.切除標本では,胃壁外に発育した8×4.8×4.8cmの腫瘤で,粘膜面に潰瘍形成が認められた.H・E染色による病理組織診断では,細胞異型,核異型を持った紡錘形の細胞から成る組織像は細胞密度が高く,核分裂像も多くみられる(18/10HPF)ことより,胃平滑筋肉腫と診断された.免疫組織学的染色を行うとS100,デスミン,平滑筋アクチンは陰性で,ビメンチン,又,幼若な間葉系細胞に染まるCD34が陽性であった