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K Fujiwara

Publications and source records attributed to K Fujiwara.

At least 235 records · Page 13Linked to original sources
PubMed1998

Enhanced invasion of Tyzzer's organism into cultured mouse hepatocytes by cytochalasin D.

The effects of cytoskeleton inhibitors on the invasion of Tyzzer's organism, an obligate intracellular bacterium, into cultured mouse hepatocytes were examined by double immunofluorescence observation and plaque assay. The two techniques gave comparable results. Invasion of bacteria was significantly enhanced by cytochalasin D, a microfilament disrupting drug, and markedly suppressed by vinblastine, a microtubule inhibitor. Another microtubule inhibitor, colchicine, did not show any substantial effect. However, the cytoskeletal system of cultured mouse hepatocytes was sensitive to these three drugs, as judged by inhibition of FITC-dextran uptake. These results suggest that Tyzzer's organisms invade host cells by a unique mechanism that is suppressed by the normal functions of host cell microfilaments.

Animals↗
PubMed1998

Tyrosine phosphorylation of platelet endothelial cell adhesion molecule-1 induced by lysophosphatidylcholine in cultured endothelial cells.

Lysophosphatidylcholine (lyso-PC), a biologically active phospholipid, appears to modulate various endothelial cell functions through tyrosine kinase-dependent signaling pathways. In cultured bovine aortic endothelial cells (BAEC), we have found that a 130 kDa protein (p130) was rapidly tyrosine phosphorylated within 2 min and sustained for, at least, 1 hr in response to 10 mumol/L of lyso-PC but not to phorbol myristate acetate (PMA). Prolonged preexposure to PMA did not affect lyso-PC-induced p130 tyrosine phosphorylation, suggesting that mechanisms independent of protein kinase C may be involved. Fractionation of the cell lysates revealed that p130 was detectable in the membrane fraction but not in the cytosolic fraction. Immunoprecipitation followed by immunoblotting of lyso-PC-treated BAEC identified p130 as bovine PECAM-1. Tyrosine phosphorylation of PECAM-1 appears to be one of the earliest events elicited by lyso-PC, and may play a role in lyso-PC-induced modulation of endothelial functions.

Animals↗
PubMed1998

Prospective randomized controlled trial comparing percutaneous acetic acid injection and percutaneous ethanol injection for small hepatocellular carcinoma.

To assess whether ultrasound-guided percutaneous acetic acid injection is superior to percutaneous ethanol injection in the treatment of small hepatocellular carcinoma (HCC), 60 patients with one to four HCCs smaller than 3 cm were entered onto a randomized controlled trial. Thirty-one and 29 patients, respectively, were treated by percutaneous acetic acid injection using 50% acetic acid or by percutaneous ethanol injection using absolute ethanol. There were no significant differences in age, sex ratio, Child-Pugh class, size of tumors, or number of tumors between the two groups. When there was no evidence of viable HCC from biopsy, plain and helical dynamic computed tomography, or angiography, the treatment was considered successful and was discontinued. All original tumors were treated successfully by either therapy. However, 8% of 38 tumors treated with percutaneous acetic acid injection and 37% of 35 tumors treated with percutaneous ethanol injection developed a local recurrence (P < .001) during the follow-up periods of 29 +/- 8 months and 23 +/- 10 months, respectively. The 1- and 2-year survival rates were 100% and 92% in percutaneous acetic acid injection and 83% and 63% in percutaneous ethanol injection (P = .0017). A multivariate analysis of prognostic factors revealed that treatment was an independent predictor of survival. The risk ratio of percutaneous acetic acid injection versus percutaneous ethanol injection was 0.120 (range, 0.027-0.528; P = .0050). In conclusion, percutaneous acetic acid injection is superior to percutaneous ethanol injection in the treatment of small HCC.

Acetic Acid↗
PubMed1998

Selective bowel decontamination of recipients for prevention against liver injury following orthotopic liver transplantation: evaluation with rat models.

Gut-derived substances can activate Kupffer cells to provoke hepatic necrosis after partial hepatectomy in rats. A similar situation may occur during orthotopic liver transplantation (OLT), as congestion in the intestinal wall, caused by portal vein occlusion, is inevitable during the operation. The contribution of such substances to liver injury following OLT was investigated in rats. Oral administration of polymyxin B sulfate for 7 days significantly altered intestinal bacterial flora in rats; Enterobacteriaceae diminished and anaerobes such as Bifidobacterium , Lactobacillus, Bacteroides, and Eubacterium increased in number, compared with the control rats. Also, this treatment significantly reduced endotoxin concentration in the portal blood 30 minutes after blood reflow following portal vein occlusion. When OLT was performed in rats using the liver preserved in cold University of Wisconsin solution for 18 hours, tissue factor activity in Kupffer cells (KC) isolated from the transplanted liver 1 hour after the operation was significantly higher than in that of normal rats. This increase was significantly reduced by pretreatment of the recipients with polymyxin B sulfate. In these recipients, serum alanine aminotransferase activity, tumor necrosis factor alpha (TNF alpha) concentration, and histological extent of liver necrosis were significantly attenuated at 24 hours after the operation compared with those of control rats. We conclude that the substances derived from bacilli sensitive to polymyxin B sulfate in the gut may be a contributing factor to liver injury following OLT in rats; we feel that this probably occurs by entering of the substances into the portal blood during the ahepatic phase of the operation to activate KC. Selective bowel decontamination of recipients with polymyxin B sulfate would be a candidate for protection against early graft failure following OLT.

Animals↗
PubMed1998

Relationship between peritoneal washing cytology through implantable port system (IPS-cytology) and second-look laparotomy in ovarian cancer patients with unmeasurable residual diseases.

OBJECTIVE: Intraperitoneal chemotherapy for minimal residual ovarian cancer has been shown to be effective. However, evaluation of the response without a second-look laparotomy (SLL) is impossible because such disease is unmeasurable by radiographic studies. In this prospective pilot study, we evaluated the relationship between implantable port system (IPS)-cytology and findings by SLL in patients with unmeasurable diseases. METHODS: Patients eligible for this study were those who had either unmeasurable residual disease at the time of initial surgery or measurable residual disease which became unmeasurable before second-look laparotomy. At the time of the initial surgery, the IPS was placed and intraperitoneal chemotherapy was administered. To obtain IPS-cytology, approximately 500 ml of saline was infused, with the patients changing their position to wash the peritoneal surface as thoroughly as possible. More than 20 ml of saline was recovered for cytological evaluation. SLL was performed after 4 to 10 courses of chemotherapy. Results of IPS-cytology obtained immediately before SLL and the SLL findings were compared. RESULTS: Forty-four patients were entered into this study. Twenty-nine patients had unmeasurable residual disease at the time of initial surgery and 15 had measurable residual disease which became unmeasurable before SLL. Only 40 patients were eligible for evaluation because catheter failure occurred in 4 patients. Three of the 26 patients who had negative IPS-cytology results were found to have positive SLL results. All 14 patients who had positive IPS-cytology results also had positive SLL results. CONCLUSIONS: IPS-cytology can detect intraperitoneal persistent disease in patients with unmeasurable residual ovarian cancer. Persistent positive IPS-cytology can indicate a negative response to chemotherapy, thus making it possible to avoid SLL. Further study with a larger number of patients is required to determine the role of negative IPS-cytology.

Adult↗
PubMed1998

MHV-induced fatal peritonitis in mice lacking IFN-gamma.

IFN-gamma gene was disrupted by homologous recombination in A3-1 embryonic stem cells. Germinally transmitted chimeric mice were successfully obtained and backcrossed with C57BL/6 (B6) mice 5 or 6 times. Deficiency of IFN-gamma in homozygous mice was confirmed by northern blot analysis of spleen cells stimulated with phorbor esther and calcium ionophore and also by IFN-gamma production in the culture supernatant of spleen cells stimulated with the same reagents. B6 mice lacking IFN-gamma were infected intraperitoneally (ip) with 10(6) PFU of JHMV and monitored for their survival. Approximately 90% of the mice died at 50 days post-infection (pi) and the mean survival time was 28 days. Mice sacrificed at 3 weeks pi showed severe peritonitis accompanying the accumulation of a viscous fluid in the abdominal and thoracic cavities. Microscopically, the disease was characterized by disseminated granulomatous inflammation and exudative fibrinous serositis in the abdominal cavity. Infectious virus was isolated in most tissues including the liver, spleen, kidney, pancreas and lung during the experimental periods. The disease was not observed in wild-type or heterozygous littermates infected i.p. with JHMV. These results suggest that IFN-gamma plays a critical role in MHV infection in mice. This experimental model may provide a unique opportunity to address the pathogenesis of virus-induced peritonitis such as feline infectious peritonitis in cats.

Acute Disease↗
PubMed1998

Successful operative treatment for acute triple-barreled aortic dissection in a patient with Marfan's syndrome: report of a case.

Triple-barreled aortic dissection is a rare form of aortic dissection associated with high mortality. We report herein the case of a 41-year-old woman with Marfan's syndrome who developed acute triple-barreled aortic dissection from a Stanford type B dissecting aneurysm. Successful graft replacement of the proximal third of the descending thoracic aorta was subsequently performed. To the best of our knowledge, this is the first case of successful operative treatment for an acute triple-barreled aortic dissection ever to be reported.

Adult↗
PubMed1998

[Evaluation of the growth of a new pulmonary trunk after the reconstruction of right ventricular outflow tract without using an external conduit].

To evaluate the growth of a pulmonary trunk reconstructed without an extracardiac conduit, the hemodynamics and diameter of a new pulmonary trunk were measured in 5 patients from the right ventriculogram and MRI at postoperative follow-up periods. There were tetralogy of Fallot with pulmonary atresia in two patients, tetralogy of Fallot with single coronary in one, truncus arteriosus type I in one and transposition of the great arteries with ventricular septal defect and pulmonary stenosis in one. The age at operation ranged from 26 days to 4.5 years. The posterior wall continuity of the right ventricle and pulmonary artery was established by the direct pulmonary-right ventricular anastomosis in three patients and by the interposition of the left atrial appendage in two. Postoperative follow-up periods ranged from 2 years and 6 months to 3 years and 10 months (median: 2 years and 11 months). In four of them, the postoperative right ventricular to aortic or left ventricular systolic pressure ratios were less than 0.4 without any significant systolic pressure gradients between pulmonary artery and right ventricle. In these four patients, the diameters of the reconstructed pulmonary trunks grew from 10-18 mm to 18-21 mm postoperatively. These diameters were more than 100% of normal values. In the remaining patient with tetralogy of Fallot and single coronary artery, the obstruction of the new pulmonary trunk by a bulged left atrial appendage, which was used as the posterior wall, was observed on the right ventricular outflow tract reconstruction without an extracardiac conduit has growth potential in the future.

Bioprosthesis↗
PubMed1998

[Changes of serum cytokine levels after thoracoscopic esophagectomy].

We introduced thoracoscopic esophagectomy with extended lymphadenectomy for reduction of respiratory dysfunction and less surgical intervention in July 1995. In this study, we investigated the changes in serum interleukin-6 (IL-6) and interleukin-1 receptor antagonist (IL-1ra) levels in 8 patients (TS Group) who underwent thoracoscopic esophagectomy with extended lymphadenectomy and compared them with the changes in patients who underwent conventional thoracotomy (CT Group). The duration of the operation and intrathoracic procedure in the TS group were significantly longer than in the CT group. However, the amount of blood loss and intrathoracic blood loss of the TS group were not significantly higher than in the CT group. The number of dissected lymph nodes was not significantly larger. The serum IL-6 levels reached maximum levels 3 hours from the end of operation. In the TS group, the changes in IL-6 levels were significantly larger (p < 0.05). On the other hand, the changes in CRP levels were also significantly larger (p < 0.01). Significant correlation was observed between the duration of the intrathoracic procedure and the maximum levels of IL-6. On the other hand, serum IL-1ra levels were not significantly. At present, these results suggest that the surgical intervention of thoracoscopic esophagectomy are more larger than that of conventional thoracotomy. We think that the length of intrathoracic procedure of thoracoscopic esophagectomy may make more large surgical stress.

Endoscopy↗
PubMed1998

[Closed Brock operation for an infant case of double outlet right ventricle with pulmonary atresia].

One-month-old boy with double outlet right ventricle and pulmonary atresia was referred to us for surgical treatment. As he had a membranous obstruction of the pulmonary artery we chose closed Brock operation as an initial procedure. A 6.5 mm in diameter of Trocar was used to open the atretic valve. Postoperative course was uneventful and his oxygen saturation was maintained satisfactory. At the age of one year and nine months he underwent corrective surgery. The pulmonary valve was widely opened enough to perform the right ventricular outflow tract reconstruction with valvotomy and outflow patch. The boy got well and was followed in the outpatient clinic. Double outlet right ventricle with membranous pulmonary atresia is a rare combination and closed Brock operation is shown to be one of the most effective procedure for this type of anomaly.

Double Outlet Right Ventricle↗
PubMed1998

Surgical treatment of a cardiac papillary fibroelastoma developing from the chordae of the tricuspid valve: report of a case.

Papillary fibroelastoma is a rare, benign cardiac tumor that can cause multiple emboli. We report herein a case of papillary fibroelastoma developing from the chordae of the tricuspid valve which was detected by echocardiography and confirmed by surgical resection. To our knowledge, this is only the fifth documented case of a tricuspid valve papillary fibroelastoma detected by echocardiography in a living patient.

Adult↗
PubMed1998

Transforming growth factor alpha levels in liver and blood correlate better than hepatocyte growth factor with hepatocyte proliferation during liver regeneration.

Transforming growth factor alpha (TGFalpha) and hepatocyte growth factor (HGF) are mitogens for hepatocytes in vitro and in vivo, produced by hepatocytes or nonparenchymal cells such as stellate cells in the liver. It is still uncertain whether TGFalpha and HGF are essential for liver regeneration. To assess the role of these growth factors in liver regeneration, their circulating and hepatic levels were studied in various rat models of liver regeneration. Hepatic and plasma HGF levels were increased with increased number of mitotic hepatocytes in rats after partial hepatectomy or carbon tetrachloride intoxication. However, hepatic HGF levels were decreased despite an increased number of mitotic hepatocytes and increased or unchanged plasma HGF levels in rats given phenobarbital and in rats after dimethylnitrosamine intoxication, which can induce hepatic necrosis after apoptosis of hepatic stellate cells. In contrast, hepatic and serum TGFalpha levels were increased in all of the models. In sham-operated rats with no increased number of mitotic hepatocytes, hepatic and circulating levels of HGF were increased, whereas those levels of TGFalpha were unchanged. The results indicate that TGFalpha levels in liver and blood more closely correlate with hepatocyte mitogenesis than HGF levels.

Animals↗
PubMed1998

Immunizing effect of vaccinia virus expressing the nucleoprotein of rinderpest virus on systemic rinderpest virus infection in rabbits.

A recombinant vaccinia virus (RVV) expressing the nucleoprotein (NP) of rinderpest virus (RPV) was examined in rabbits for the involvement of the NP protein in protection from the RPV infection. Despite their production of anti-NP antibody, the RVV-immunized rabbits succumbed to the RPV challenge, although there was a slight delay in the onset of disease after the low-dose challenge. On the other hand, the animals immunized with RVV expressing the hemagglutinin (H) protein of the RPV were completely protected. These results indicate that the NP protein might be not so effective as the H protein for the protection against viremic and systemic infection with RPV.

Animals↗
PubMed1998

The two different states of hepatitis B virus DNA in asymptomatic carriers: HBe-antigen-positive versus anti-HBe-positive asymptomatic carriers.

During the course of hepatitis B virus (HBV) infection, there exists a long period of normal liver function tests with different states of HBeAg/Ab. As the state of HBV in asymptomatic carriers was not well characterized, we quantitatively and qualitatively examined HBV in both HBeAg-positive and anti-HBe-positive asymptomatic carriers. Sera from 10 HBeAg-positive and 27 anti-HBe-positive asymptomatic carriers were analyzed. The amount of HBV DNA was determined by dot-blot hybridization and polymerase chain reaction. The mutations in precore and core regions, spanning 636 nucleotides, of hepatitis B virus were examined by directly sequencing the amplified HBV DNA. HBV DNA was detected in all 10 HBeAg-positive cases, whereas it was found in only 7 of 27 (26%) anti-HBe-positive cases by the nested PCR method. The mean amount of HBV DNA in HBeAg-positive cases was 10(9.1 +/- 0.7) copies/ml, while that in anti-HBe-positive cases was 10(1.0 +/- 1.5) copies/ml. There were no missense mutations in the entire precore and core genes of HBV DNA taken from HBeAg-positive asymptomatic carriers. In contrast, many mutations (mean 9.0 +/- 3.3, range 6-14) were detected in the core gene of seven anti-HBe-positive asymptomatic carriers including two cases with increments of the mutations. Analysis of the precore region revealed three wild-type and four mutant-type (including one coexisting with wild-type) cases. These data suggest that HBV exists in quite different ways in "asymptomatic" carriers; in the HBeAg-positive phase HBV probably coexists with the host and remains as the wild type, whereas in the anti-HBe-positive phase a drastically reduced amount of HBV with many mutations remains, probably as a consequence of the long-lasting interaction with the host. Nevertheless, such small amount of virus could cause fulminant hepatic failure. It is important to make further clinical and virological investigations in order to understand the state of asymptomatic carrier.

Adult↗
PubMed1998

Etiologic considerations of fulminant non-A, non-B viral hepatitis in Japan: analyses by nucleic acid amplification method.

The etiology of fulminant non-A, non-B hepatitis has remained unclear, even after the identification of hepatitis C and E viruses. To study the possible involvement of hepatitis B, C, D, and E virus infections, viral genomes were amplified by a sensitive polymerase chain reaction method in sera and liver tissues obtained from 20 patients serologically diagnosed with non-A, non-B fulminant hepatitis (n = 14), acute hepatitis severe type (n = 2), and ordinary acute hepatitis (n = 4). Hepatitis C or E virus RNA could not be detected in sera obtained at admission from these patients. Hepatitis B virus DNA was detected in sera from 3 patients with fulminant hepatitis and in liver from 9 patients with fulminant hepatitis or acute hepatitis severe type. These results suggest that HCV might not be involved in fulminant non-A, non-B hepatitis, and HBV might be related to some of the serologic "non-A, non-B" viral hepatitis cases in Japan.

Adult↗