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K Fukao

Publications and source records attributed to K Fukao.

At least 55 records · Page 3Linked to original sources
PubMed2000

Flow-cytometric separation and enrichment of hepatic progenitor cells in the developing mouse liver.

Stem cells responsible for tissue maintenance and repair are found in a number of organs. However, hepatic stem cells assumed to play a key role in liver development and regeneration remain to be well characterized. To address this issue, we set up a culture system in which primitive hepatic progenitor cells formed colonies. By combining this culture system with fluorescence-activated cell sorting (FACS), cells forming colonies containing distinct hepatocytes and cholangiocytes were identified in the fetal mouse liver. These cells express both CD49f and CD29 (alpha6 and beta1 integrin subunits), but do not mark for hematopoietic antigens such as CD45, TER119, and c-Kit. When transplanted into the spleen, these cells migrated to the recipient liver and differentiated into liver parenchymal cells. Our data demonstrate that hepatic progenitor cells are enriched by FACS and suggest approaches to supplanting organ allografting and improving artificial-organ hepatic support.

Animals↗
PubMed2000

Enteral vitamin B12 supplements reverse postgastrectomy B12 deficiency.

OBJECTIVE: To examine the development of chemical and clinical vitamin B12 deficiency after total gastrectomy, and to evaluate the efficacy of supplemental oral B12 administration. SUMMARY BACKGROUND DATA: Postgastrectomy anemia is due to deficiencies of iron and vitamin B12, and parenteral B12 administration is the only appropriate treatment. However, no guidelines exist for the prophylactic use of B12 in patients who undergo total gastrectomy, the clinical presentation of B12 deficiency in this context has not been defined, and the question of whether oral B12 administration can be used to prevent and treat B12 deficiency has not been examined. METHODS: Serum B12 concentrations were measured in 31 patients who had undergone total gastrectomy. Symptoms related to B12 deficiency were surveyed in detail. Serum B12 concentrations were measured every 6 months after total gastrectomy in 10 patients. Thirty one patients received supplemental B12: 18 patients orally and 13 by intramuscular injection. RESULTS: The B12 concentration dropped below the lower limit of normal (200 pg/mL) for the first time in two patients at 1 year, in four patients at 2 years, in three patients at 3 years, and in one patient at 4 years. Seventy-eight percent of patients reported some symptoms related to B12 deficiency. The serum B12 concentration in patients who received supplemental B12 orally increased rapidly and all symptoms resolved with oral therapy alone. CONCLUSIONS: B12 deficiency can develop as early as 1 year after total gastrectomy and causes symptoms. Because enteral B12 treatment increases the serum B12 concentration and leads to rapid resolution of symptoms, it should be prescribed routinely to patients undergoing total gastrectomy.

Administration, Oral↗
PubMed2000

Glass transitions and dynamics in thin polymer films: dielectric relaxation of thin films of polystyrene

The glass transition temperature T(g) and the temperature T(alpha) corresponding to the peak in the dielectric loss due to the alpha process have been simultaneously determined as functions of film thickness d through dielectric measurements for polystyrene thin films supported on glass substrate. The dielectric loss peaks have also been investigated as functions of frequency for a given temperature. A decrease in T(g) was observed with decreasing film thickness, while T(alpha) was found to remain almost constant for d>d(c) and to decrease drastically with decreasing d for d<d(c). Here, d(c) is a critical thickness dependent on molecular weight. The relaxation time tau(alpha) of the alpha process, which was measured as the frequency at which the dielectric loss realizes its peak value at a given temperature, was found to have a d dependence similar to that of T(alpha). The relaxation function for the alpha process was obtained by using the observed frequency dependence of the peak profile of the dielectric loss. The exponent beta(KWW), which was obtained from the relaxation functions, decreases as thickness decreases. This suggests that the distribution of relaxation times for the alpha process broadens with decreasing thickness. The thickness dependence of T(g) is directly related to the distribution of relaxation times for the alpha process, not to the relaxation time itself. The value of the thermal expansion coefficient normal to the film surface was found to increase with decreasing film thickness below T(g), but to decrease with decreasing film thickness above T(g). These experimental results are discussed in the context of a three-layer model in which within thin films there are three layers with different mobilities and glass transition temperatures.

Journal Article↗
PubMed2000

Cyclooxygenase expression in the gallbladder.

The COX expressions were evaluated separately in the epithelium and in the stroma of gallbladder cancer, chronic cholecystitis, xanthogranulomatous cholecystitis (XGC) and the normal gallbladder. In normal gallbladder COX-2 expression rate was significantly higher in the epithelium than in the stroma. The COX-2 expression rate in the epithelium of non-cancerous adjacent epithelium to cancerous lesion was significantly lower than those not only of cancer, but also chronic cholecystitis, XGC and normal gallbladder. In stroma, the COX-2 expression rate in cancer, chronic cholecystitis and XGC were significantly higher than that of the normal gallbladder. The rate in non-cancerous adjacent stroma to cancer is significantly lower than that of cancer and XGC. However, the difference of rate between of normal and of chronic cholecystitis was not significant. The COX-2 expression rates were significantly higher in both the epithelium and the stroma in the well and moderately differentiated cancer group than in the poorly and undifferentiated cancer group. Our results suggest that COX-2 expression in the gallbladder may be regulated by various factors and not directly related to carcinogenesis. The significance of its repression in the non-cancerous adjacent tissue to cancer lesion should be re-evaluated.

Cholecystitis↗
PubMed2000

Enhanced radiation killing by 5-fluorouracil of biliary tract cancer cell lines.

Despite the frequent clinical use of 5-fluorouracil (5-FU) in combination with radiotherapy for patients with biliary tract cancers, data remain scarce concerning specifically the influence of 5-FU on the sensitivity of these cancer cells to radiation. The present study was carried out to evaluate the effects of concomitant treatment with 5-FU on radiation-induced cell killing in two established human biliary tract cancer cell lines (Mz-ChA-2 and SK-ChA-1 cells). These lines were chosen as we have previously shown that SK-ChA-1 cells are significantly more resistant to both radiation and 5-FU than Mz-ChA-2 cells. Clonogenic survival was employed as the end-point for cell killing. Administration of 5-FU at LD50 doses to each cell line significantly enhanced radiation-induced cell killing. The enhancement ratio (ER) was obtained by dividing the radiation dose required to decrease the cell survival fraction to 37% (D0) by the dose to decrease cell survival to the same level when the cells were also treated with 5-FU. The ER in each of the cell lines was greater when they were incubated with 5-FU after radiation rather than prior to radiation. Longer exposure times with 5-FU resulted in enhanced radiation killing. The ER was significantly higher in the radioresistant cell line than in the radiosensitive line. These findings suggest that therapy with radiation and 5-FU may be of value as components of multidisciplinary treatment for biliary tract cancer. Protracted low dose exposure to 5-FU may prove to be most efficacious in enhancing the effects of radiation therapy.

Biliary Tract Neoplasms↗
PubMed1999

Soluble forms of CD95 and CD95 ligand after living related liver transplantation.

BACKGROUND: Soluble forms of CD95 and CD95 ligand (sCD95 and sCD95L, respectively) can increase in the serum of patients with some inflammatory disease. In this study, we investigated the serum levels of sCD95 and sCD95L in liver transplantation recipients. METHODS: Serum levels of sCD95 and sCD95L in living related liver transplant recipients were analyzed by ELISA and their relation to the clinical findings estimated. RESULTS: Serum samples from the recipients did not show detectable levels of sCD95L but showed significantly increased levels of sCD95. The increase of sCD95 was positively associated with that of total-bilirubin and incidence of rejection, infection, and graft ischemia. CONCLUSIONS: The present results indicate an existence of sCD95 in the recipients of living related liver transplants. The increased serum levels of sCD95 may modify the immunological situation of the recipients after transplantation or represent the ongoing graft damage.

Adolescent↗
PubMed1999

Endothelin antagonist treatment for successful liver transplantation from non-heart-beating donors.

BACKGROUND: With the shortage of cadaveric donors, non-heart-beating donors (NHBDs) are a potential source of liver allografts. However, warm ischemic injury in NHBDs seriously affects the viability of graft liver. Endothelin (ET)-1 has been reported to be involved in the hepatic microcirculatory disturbances after ischemia-reperfusion. METHODS: In a porcine orthotopic liver transplantation model, changes in the serum and liver tissue ET-1 concentration were measured and the effects of an ET receptor antagonist, TAK-044, were evaluated. After cardiac arrest of the donors, liver allografts were subjected to 90 min of warm ischemia, flushed, and preserved for 4 hr at 4 degrees C. The pigs were divided into two groups: a control group (no drug treatment) and a drug-treated group, in which donors and recipients were treated with TAK-044 (10 mg/kg body, drip intravenous injection). Both groups had six donor/recipient pairs. RESULTS: -The ET-1 concentration in the hepatic venous blood increased after reperfusion of the graft in the control group recipients. ET-1 in the graft liver significantly increased during the cold preservation period. TAK-044 treatment significantly increased recipient 7-day survival rate. After reperfusion of the graft, the concentrations of serum liver enzymes and arterial lactate in the drug-treated group were significantly lower than in the control group. The postoperative increase in portal venous pressure was significantly reduced in the drug-treated group. Measurements of liver enzymes in the washed-out preservation fluid at the time of graft rinsing indicated that TAK-044 treatment of the donors significantly suppressed liver enzyme release during ischemia. CONCLUSIONS: These findings indicate TAK-044 treatment has protective effects on postoperative function of hepatic allografts procured from NHBDs.

Alanine Transaminase↗
PubMed1999

Primary malignant hemangiopericytoma of the breast: report of a case.

A 70-year-old woman presented with a huge tumor in her left breast, which had rapidly increased in size causing cutaneous erosion. She underwent a simple mastectomy, at which time the tumor was found to be an encapsulated multilocular cystic lesion containing dark fluid. Histological examination disclosed the characteristic features of malignant hemangiopericytoma, including the perivascular lamellar growth of atypical mesenchymal cells with vimentin-positive cytoplasm. Multiple irregular vascular luminal formation was also conspicuous. The characteristics of this lesion are discussed together with a review of the previous literature on this unusual neoplasm.

Aged↗
PubMed1999

The prevention of postoperative intraperitoneal adhesions by tranilast: N-(3',4'-dimethoxycinnamoyl)anthranilic acid.

The development of postoperative intraperitoneal adhesions continues to be a major concern for surgeons. The purpose of this study was to establish a postoperative adhesion model in rats, and to assess the effectiveness of tranilast (N-(3',4'-dimethoxycinnamoyl)anthranilic acid) in preventing postoperative adhesion formation. The adhesion model was established in 12 male Donryu rats. This involved two essential factors, drying and bleeding. Another 22 male Donryu rats were used to study the prevention of intraperitoneal adhesions. Tranilast was administered orally pre- and postoperatively. Adhesion strength was evaluated by grading, and basic fibroblast growth factor (bFGF) and transforming growth factor-beta-1 (TGF-beta1) concentration were measured. Postoperative intraperitoneal adhesions were seen in all rats, but the adhesions in the tranilast group were significantly less severe than those in the control group. Serum bFGF and TGF-beta1 levels in the tranilast group were lower at the time of surgery than those in the control group, and bFGF levels were lower at the endpoint of this study in the tranilast group than in the control group. The TGF-beta1 levels at the end-point did not differ between the two groups. These findings demonstrated that tranilast significantly reduced postoperative intraperitoneal adhesion formation.

Abdomen↗
PubMed1999

Evaluation of esophageal bile reflux after total gastrectomy by gastrointestinal and hepatobiliary dual scintigraphy.

Conducting the qualitative evaluation of reconstruction methods is difficult because of their complexity. The aim of the present study was to compare esophageal bile and food reflux by performing gastrointestinal and hepatobiliary dual scintigraphy (GHDS) after various methods of reconstruction following total gastrectomy. Of 17 patients studied, 4 had undergone Roux-en-Y anastomoses (R-Y); 6, jejunal pouch-Y anastomoses (P-Y); and 7, jejunal pouch interposition (P-I). GHDS was performed 1 year after surgery using 111In-diethylene triamine pentaacetic acid administered orally, and 99mTc-pyridoxyl-5-methyl tryptophan administered intravenously. Imaging data from a gamma camera were stored in and processed by a data analyzer. Three patients who had undergone R-Y and one who had undergone P-I complained of heartburn, while one who had undergone R-Y, two who had undergone P-Y, and three who had undergone P-I complained of a feeling of fullness. Esophageal bile reflux was confirmed by GHDS in four of the patients who had undergone R-Y, one who had undergone P-Y, and four who had undergone P-I. Moreover, GHDS demonstrated food retention in two patients who had undergone R-Y, five who had undergone P-Y, and four who had undergone P-I. Weight loss was closely related to the esophageal reflux of bile or food which can be accurately detected by GHDS. Despite the absence of heartburn, patients diagnosed as having bile reflux by GHDS showed poor recovery of body weight.

Adult↗
PubMed1999

An endothelin receptor antagonist ameliorates injuries of sinusoid lining cells in porcine liver transplantation.

BACKGROUND: TAK-044 is an endothelin receptor antagonist. Whether the agent has protective effects on liver graft injuries from non-heart-beating donors is unknown. METHODS: In donor pigs, cardiac arrest was induced by stopping the respirator. Forty-five minutes after cessation of the respirator, the liver was flushed with University of Wisconsin (UW) solution, preserved for 8 hours at 4 degrees C, and transplanted orthotopically. The pigs were divided into two groups: a control group and a drug-treated group in which TAK-044 was given in the UW solutions (10 mg/L) and was administered to recipients (10 mg/kg body weight). RESULTS: TAK-044 treatment significantly increased recipient survival rate. After reperfusion of the graft, portal venous pressure and 15-minute retention rate of indocyanine green were significantly reduced in the drug-treated group. Electron microscopic findings indicated that TAK-044 attenuated endothelial cell injuries. CONCLUSION: TAK-044 treatment improves the viability of livers harvested from non-heart-beating donors. The main effect of the agent is protection of endothelial cells from ischemia/reperfusion injuries.

Animals↗
PubMed1999

Ictal paraphasia induced by language activity.

Four patients with ictal speech disturbance were studied. Their seizures featured isolated, or series of, brief episodes of fluent paraphasia, paragraphia, and comprehension deficit. These episodes were often induced by language activity. Six patients with ictal paraphasia or paragraphia, as a recurrent habitual seizure, are reported in the literature. All ten cases, including the four cases described here and the six cases reported in the literature, featured patients who uttered meaningless speech fluently or displayed paragraphia. The syllables uttered during seizures contained many neologisms and resembled the neologistic jargon of patients with fluent aphasias of the Wernicke type. Nine patients had clusters or status of brief seizures and four patients had auditory hallucination as an ictal event. The seizures in six patients were easily induced by the use of language. Seizure focus was on the left side in all patients mentioned. The possibility of another type of language-induced seizures than those seen in reading epilepsy or language-induced epilepsy is suggested in which myoclonias of the jaw and face, or upper extremities are the main seizure types.

Adult↗
PubMed1999

Treatment of gallbladder cancer by radical resection.

BACKGROUND: The use of radical resection for gallbladder cancer is controversial. This study evaluated results of resection for gallbladder cancer and analysed prognostic factors. METHODS: A retrospective review of 135 patients who underwent surgical resection for gallbladder cancer between 1976 and 1998 was performed. Of these, 123 patients underwent radical resection and the remaining 12 had palliative resection. The resections included 32 hepatopancreatoduodenectomies and 57 with adjuvant radiotherapy. Twelve prognostic factors were analysed. A subset of 96 patients with stage IV disease was analysed separately with respect to residual tumour level and adjuvant radiotherapy. RESULTS: Surgical resection was associated with a 5-year survival rate of 36 per cent, with a mean follow-up time of 870 days. Twenty-two patients have survived more than 5 years including three with stage IV disease. Overall operative morbidity and mortality rates were 13 and 4 per cent respectively. The 5-year survival rate decreased with disease stage: 100, 78, 69 and 11 per cent for stages I (n = 13), II (n = 19), III (n = 7) and IV (n = 96) respectively. Performance status, jaundice, histopathological type and grade, primary tumour, lymph node, distant metastasis, stage grouping, residual tumour level and adjuvant radiotherapy were significant prognostic factors. CONCLUSION: With careful patient selection, radical resection for gallbladder cancer improves the prognosis with acceptable operative mortality and morbidity rates, even for stage IV disease, provided that complete gross tumour resection is combined with radiotherapy.

Adult↗
PubMed1999

Photosensitive and nonphotosensitive electronic screen game-induced seizures.

PURPOSE: To disclose possible epileptologic differences between photosensitive and nonphotosensitive patients with seizures induced by electronic screen games (ESGs). METHODS: In patients with ESG-induced seizures who showed photo- and pattern sensitivity, magnetoencephalography (MEG) and EEG were performed simultaneously during ESG play, and equivalent current dipoles (ECDs) of the MEG spikes were estimated. In patients without ESG-induced seizures, who were surgical candidates, the intracranial EEG was analyzed for changes in epileptiform spike frequency. RESULTS: Fifteen of 29 patients were photo- or pattern sensitive, and they had a posterior predominance of ECDs of the MEG spikes. In contrast, nonphotosensitive patients had an anterior predominance of ECDs. Other seizure-precipitating factors in the nonphotosensitive patients included hand manipulation or spatial processing. In patients without a history of ESG-induced seizures who underwent intracranial EEG monitoring for surgical evaluation, ESG playing induced changes in spike frequency in the supplementary motor area, perisylvian region, and medial temporal lobe. CONCLUSIONS: In photosensitive patients, interictal MEG spikes arise predominantly from the posterior region of the brain. In nonphotosensitive patients, epileptiform spikes tend to originate in the anterior part of the brain. Thus factors involving functions of the anterior part of the brain other than photo- or pattern sensitivity may play a role in the induction of seizures during ESG play. Furthermore, the changes in spike frequency in specific brain areas may correspond to their involvement in praxic activity and emotional changes during ESG play. A chance occurrence of seizures during ESG play also was observed.

Adolescent↗
PubMed1999

Killing effects of 5-fluorouracil on human biliary tract cancer cell lines.

Data concerning the cellular sensitivity of human biliary tract cancer cell lines to 5-FU are scarce. The purpose of the present study was to evaluate the cellular sensitivity of Mz-ChA-2 (derived from gall bladder cancer) and SK-ChA-1 (derived from bile duct cancer) to 5-FU. The clonogenic capacity of these lines after pulse (1 h) or continuous (168 h) administration of various 5-FU concentrations (0.1-100 microg/ml) was evaluated in exponentially growing cells as well as in those that had reached the plateau phase. In both cell lines, exponentially growing cells were 1.8-times more susceptible to 5-FU than those in plateau phase. However, when cells in the same growth phase were compared, Mz-ChA-2 cells were 10 times more sensitive to the drug than SK-ChA-1 cells. Regardless of the growth phase or cell line, increasing the duration of exposure to 5-FU decreased the proportion of surviving cells. Even at a non-cytocidal dosage, exposing the cells for three doubling times markedly decreased the number of viable cells remaining after treatment.

Antimetabolites, Antineoplastic↗
PubMed1999

Prognostic significance of perirectal lymph node micrometastases in Dukes' B rectal carcinoma: an immunohistochemical study by CAM5.2.

Lymph node metastasis is an important prognostic factor for rectal carcinoma, but only a few attempts at defining the relationship between lymph node micrometastases and prognosis have been made. The purpose of this study was to examine the correlation between the presence of micrometastases and prognosis in patients with rectal carcinoma. Six hundred forty-four lymph nodes were dissected from 42 patients with Dukes' B rectal carcinoma and stained immunohistochemically using a monoclonal antibody, CAM5.2, that binds cytokeratin. Clinicopathological factors, rate of recurrence, and prognosis were compared among patients with and without micrometastases. Micrometastases were detected in 19 lymph nodes (19 of 644 = 2.9%) from 9 patients (9 of 42 = 21.4%). The presence of micrometastases was not related to clinicopathological factors. There were significant differences in recurrence rates (5 of 9 versus 5 of 33, P = 0.02), relapse-free survival rates (P = 0.04), and 10-year survival rates (P = 0.03) between patients with and without micrometastases. Immunohistochemistry successfully identified micrometastatic foci in lymph nodes missed with conventional staining methods. The existence of micrometastases influenced the prognosis in patients with Dukes' B rectal carcinoma.

Antibodies, Monoclonal↗
PubMed1999

[Chemoradiation therapy for advanced esophageal cancers--report of 3 cases].

Three cases of prominent-type advanced esophageal cancer were treated with chemoradiation therapy using a 5-FU analog and low dose CDDP. All cases showed a complete response after the treatment. Only mild bone marrow suppression was found in one case. This protocol will be applied for patients with prominent-type advanced esophageal cancers, especially high risk patients.

Aged↗