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S Tamura

Publications and source records attributed to S Tamura.

At least 91 records · Page 5Linked to original sources
PubMed2001

Impact of histological grade of hepatocellular carcinoma on the outcome of liver transplantation.

HYPOTHESIS: Histological grade of hepatocellular carcinoma (HCC) is an important prognostic factor affecting patient survival after orthotopic liver transplantation (OLT). DESIGN: Retrospective analysis. SETTING: University-based teaching hospital. PATIENTS: Of 952 OLTs performed between June 1991 and January 1999, 56 OLT recipients had histologically proven HCC in the explant liver. Of those, 53 patients with complete clinicopathologic data were analyzed. A single pathologist blinded to the outcome of each patient reviewed all histological specimens. RESULTS: Median follow-up was 709 days. Overall survival for patients with tumors sized 5 cm or less at 1, 3, and 5 years was 87%, 78%, and 71%, respectively (Kaplan-Meier). Univariate analysis revealed the size, number, and distribution of tumors; the presence of microscopic vascular invasion and lymph node metastasis; histological differentiation; and pTNM stage to be statistically significant factors affecting survival. Multivariate analysis revealed histological differentiation and pTNM stage to be the independent and statistically significant factors affecting survival (P =.002 and.03, respectively). When pTNM stage was excluded from multivariate analysis, histological differentiation and size remained the significant independent factors (P =.02 and.03, respectively). Three-year survival for patients with small (</=5 cm) tumor with well- to moderately differentiated and poorly differentiated HCC was 82% and 67%, respectively. Three-year survival for patients with large (>5 cm) tumor with well- to moderately differentiated and poorly differentiated HCC was 62.5% and 0%, respectively. CONCLUSIONS: In our retrospective experience, histological differentiation had a statistically significant effect on the prognosis of HCC after OLT. However, before altering the current OLT selection criteria for patients with HCC, prospective studies are required to confirm the impact of histological grade on clinical outcome.

Carcinoma, Hepatocellular↗
PubMed2001

Invited response

Explore the source record for details and available documents.

Journal Article↗
PubMed2001

Neurometer measurement of current stimulus threshold in rats.

We examined the current stimulus threshold in rats with the Neurometer, a device used clinically for measuring perception and pain thresholds. Although many studies have indicated the usefulness of this device in the quantification of nerve dysfunction in patients, we have found no published reports on the use of the Neurometer in animals. Transcutaneous nerve stimuli of the three sine-wave pulses produced by the Neurometer (at 2000, 250, and 5 Hz) were applied to plantar surface of rats. The intensity of each stimulation at which rats vocalized or were hardly startled was defined as the current stimulus threshold. With repeated stimulation, the thresholds were almost constant. Repeated topical application to the area around the stimulating electrode of a high concentration of capsaicin, which acts on small-diameter fibers, increased the thresholds at 250 and 5 Hz, but did not affect the 2000-Hz threshold. Intravenous morphine (2-5 mg/kg) increased all three thresholds, whereas intrathecal morphine (20 or 80 microg) increased only the 5-Hz threshold. Intravenous injection of a minor tranquilizer, diazepam, at 1 mg/kg raised the thresholds at 2000 and 250 Hz, but did not affect the 5-Hz threshold. Higher dose of diazepam increased all three thresholds. These results suggest that the Neurometer makes possible selective examination of subsets of nerve fibers that differ in diameter not only in humans but also in animals. The present study in rats, in which we established a method of measurement, may provide helpful suggestions for the interpretation of data in humans.

Animals↗
PubMed2001

Effects of ATP on regulation of galactosyltransferase-I activity responsible for synthesis of the linkage region between the core protein and glycosaminoglycan chains of proteoglycans.

We report that ATP enhances the activity of galactosyltransferase-I, which synthesizes the linkage region between glycosaminoglycan chains and the core proteins of proteoglycans. The enzyme activity in cell-free fractions prepared from cultured human skin fibroblasts was measured by high-performance liquid chromatographic detection of galactosyl-xylosyl-(4-methylumbelliferone) produced from 4-methylumbelliferyl-beta-D-xyloside used as an acceptor. ATP at 2 mM increased the enzyme activity by about 60% in the 110 x g supernatant of the cell homogenate, but not in the supernatant or precipitate fractions obtained by 100,000 x g centrifugation. When both fractions (the 100,000 x g supernatant and precipitate) were mixed, the additional ATP increased the enzyme activity. This increase was canceled by heat treatment or trypsin digestion of the 100,000 x g supernatant. In addition, the 100,000 x g precipitate, which was prepared from the 110 x g supernatant preincubated with ATP, exhibited increased activity, and this increase was abolished by alkaline phosphatase treatment. These results suggest that a protein kinase in the 100,000 x g supernatant activates galactosyltransferase-I activity.

Adenosine Triphosphate↗
PubMed2001

Corticosteroid therapy in patients with IgA nephropathy and impaired renal function.

AIM: IgA nephropathy (IgAN) is a common type of primary glomerulonephritis that constitutes a major cause of end-stage renal disease. Oral and/or intravenous glucocorticoid therapy can protect against progression of IgAN in patients with preserved renal function. We evaluated steroid therapy in IgAN with established renal dysfunction. PATIENTS AND METHODS: We retrospectively analyzed the effect of methylprednisolone (MP) pulse therapy in 8 IgAN patients with serum creatinine concentrations (sCr) 2.76 +/- 1.32 mg/dl (mean +/- SD). In each patient renal function had progressively deteriorated in the 12 months preceding treatment, as indicated by negative slopes of 1/sCr plotted against time (regression coefficients). RESULTS: Regression coefficients during the 12 months following therapy improved significantly from -0.02333 +/- 0.00732 to -0.00036 +/- 0.00423 dl/mg/month, respectively. The mean difference in slope was 0.0230 +/- 0.0076 dl/mg/month (95% confidence interval, 0.0165 to 0.0295, p < 0.001). Proteinuria also significantly decreased from a mean urine protein/creatinine ratio of 2.57 +/- 1.12 before therapy to 1.12 +/- 0.84 6 months after therapy (p < 0.005). Other factors that might affect progression of renal dysfunction remained unchanged during the observation periods. CONCLUSION: Corticosteroids may attenuate progression of renal failure and delay the need for dialysis in this patient population, although a large randomized trial is necessary.

Administration, Oral↗
PubMed2001

Circulating transforming growth factor beta 1 as a predictor of liver metastasis after resection in colorectal cancer.

Plasma transforming growth factor beta1 (TGF-beta1) has been reported to be correlated with the extent of disease in colorectal cancer, but it is not known whether measuring this cytokine can help predict liver metastasis after curative resection. We prospectively studied whether plasma TGF-beta1 levels could predict liver metastasis in 117 patients with colorectal cancer before and after curative resection. Blood samples were drawn before and 2 weeks after surgery to determine the cytokine levels. Abdominal ultrasonography or computed tomography was done every 3 months after surgery. The primary end point for follow-up was recurrence. Seventy-seven of 117 cases (66%) had preoperative levels of the cytokine higher than the borderline limit of 7.5 ng/ml. Postoperative levels were >7.5 ng/ml in 29 of 117 patients (25%). The median follow-up period was 42 months (range, 5--66 months), with follow-up of all 117 patients. No recurrence was observed in 13 patients with Dukes' stage A lesions. Liver metastasis occurred in 18 of 104 patients (17%) with Dukes' stage B or C disease. Fourteen of 18 patients (78%) who developed liver metastasis had shown a postoperative plasma TGF-beta1 level of >7.5 ng/ml. Cox proportional hazards regression analysis showed that the postoperative level was a significant predictive factor for liver metastasis (P < 0.001). A single point measurement of plasma TGF-beta1 levels at 2 weeks after curative resection seems to be able to predict liver metastasis in colorectal cancer. This finding suggests the value of a prospective trial of liver-targeted adjuvant therapy for patients with elevated postoperative plasma TGF-beta1 levels.

Aged↗
PubMed2001

[Examination of the power of families taking care of patients at home at peace].

OBJECTIVE: We examined the power of families who take care of a patient at home. We wanted to know how much caring power patients needed to stay at home at peace. PATIENTS AND METHODS: The subjects were 150 patients who visit the hospital for day care or are taken care of at home under our management. We examined their age, sex, main disease, the points of their families power for their care, the assessment of how peaceful at home, use of care services, and special things. RESULTS: Most of the patients were in their 80's or 70's. Stroke was the main disease. The most care grade are second grade. Higher care grade are smaller number. About 50% of the families paid for care services. The assessment of low care grade patients did not depend on the power of the families. But the assessment of high care grade patients did depend on that. We concluded that it is difficult to take care at home of high care grade patients who does not have some powers on families for his care. If the patient and his/her family want to use care services, they have to pay 10% charge. It is difficult to alleviate the burden they pose on their family.

Aged↗
PubMed2001

[Reevaluation of 201Tl-SPECT for patients with solitary pulmonary nodule--comparison study with biopsy method and tumor marker measurement].

We compared the differential diagnostic capabilities of 201Tl-SPECT and biopsy methods and serum tumor marker in 125 patients with solitary pulmonary lesions composed of 87 lung cancer and 38 benign lesions. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of 201Tl-SPECT were 76%, 95%, 97%, 63%, and 82%, respectively. These parameters are similar in biopsy methods. Although sensitivity improved to be 85% by the combination with tumor marker methods, both specificity and accuracy deteriorated to be 55% and 76%. Using combination method with 201Tl-SPECT and biopsy, sensitivity, NPV and accuracy improved to be 84%, 70% and 85%. Based on its high PPV value, 201Tl-SPECT could be useful when biopsy method could not prove lung cancer or in case whose biopsy is considered to be invasive. Because of the lower NPV value owing to false negative cases in some adenocarcinoma, negative 201Tl-SPECT case should be followed up carefully.

Biomarkers, Tumor↗
PubMed2000

A novel low-density lipoprotein receptor-related protein mediating cellular uptake of apolipoprotein E-enriched beta-VLDL in vitro.

We report here the identification of a novel member of the low-density lipoprotein receptor (the LDL receptor) family through signal sequence trap screening of a mouse lymphocyte cDNA library. The protein was termed LDL receptor-related protein 9 (LRP9). LRP9 is a type I membrane protein predicted to contain 696 amino acids with a calculated molecular mass of 74 764 Da. The NH(2)-terminal half of LRP9 contains two CUB domains separated by a single ligand-binding repeat. The second CUB domain is followed by a cluster of three additional ligand-binding repeats and a transmembrane domain. The COOH-terminal intracellular region contains a proline-rich region. LRP9 mRNA was expressed in the liver, kidney, lung, and heart at high levels, and in the spleen and brain at low levels. In situ hybridization analysis of mouse liver, kidney, and brain detected LRP9 transcripts in hepatocytes, sinusoidal lining cells, peritubular capillaries, choroid plexus, ependyma of the third ventricle, pia matter, and hippocampus. In particular, high levels of expression were observed in the vascular walls. Apolipoprotein E (apoE)-enriched beta-VLDL stimulated cellular cholesteryl ester formation in ldl-A7/LRP9. These results raise the possibility that this newly identified receptor, which is expressed in the liver, may play a physiological role in the uptake of apoE-containing lipoproteins.

Adult↗
PubMed2000

New multidrug resistance modulators from Atractylodis Lanceae Rhizoma.

Three new oligoacylated sucroses designated atractysucroses-I, -II, and -III were obtained from Atractylodis Lanceae Rhizoma as multidrug resistance (MDR) modulating substances against human carcinoma cell lines and their chemical structures were characterized as a mixture of acyl groups. Atractysucrose-I modulates MDR in KB-C2 cells as strongly as verapamil. This is the first example of an MDR-modulator classified as a carbohydrate.

Asteraceae↗
PubMed2000

Regulation of the TAK1 signaling pathway by protein phosphatase 2C.

Protein phosphatase 2C (PP2C) is implicated in the negative regulation of stress-activated protein kinase cascades in yeast and mammalian cells. In this study, we determined the role of PP2Cbeta-1, a major isoform of mammalian PP2C, in the TAK1 signaling pathway, a stress-activated protein kinase cascade that is activated by interleukin-1, transforming growth factor-beta, or stress. Ectopic expression of PP2Cbeta-1 inhibited the TAK1-mediated mitogen-activated protein kinase kinase 4-c-Jun amino-terminal kinase and mitogen-activated protein kinase kinase 6-p38 signaling pathways. In vitro, PP2Cbeta-1 dephosphorylated and inactivated TAK1. Coimmunoprecipitation experiments indicated that PP2Cbeta-1 associates with the central region of TAK1. A phosphatase-negative mutant of PP2Cbeta-1, PP2Cbeta-1 (R/G), acted as a dominant negative mutant, inhibiting dephosphorylation of TAK1 by wild-type PP2Cbeta-1 in vitro. In addition, ectopic expression of PP2Cbeta-1(R/G) enhanced interleukin-1-induced activation of an AP-1 reporter gene. Collectively, these results indicate that PP2Cbeta negatively regulates the TAK1 signaling pathway by direct dephosphorylation of TAK1.

Adaptation, Biological↗
PubMed2000

A transgenic mouse expressing human CYP1A2 in the pancreas.

A transgenic mouse line expressing the human cytochrome P450 CYP1A2 in the pancreas under the control of the mouse elastase promoter was established. The expression of CYP1A2 was specific to the transgenic pancreas and was not found in the control wild-type mouse pancreas. The level of CYP1A2 expressed in pancreatic microsomes from transgenic mice was comparable to that of the endogenously expressed CYP1A2 protein in the liver, as judged by western blotting analyses. Estrone metabolism was used to determine the activity of CYP1A2 expressed in the pancreas of the transgenic mouse. The transgenic pancreas exhibited almost one-third to one-half of the activity of wild-type or CYP1A2 transgenic mouse liver, whereas the wild-type pancreas demonstrated no activity. The addition of NADPH-cytochrome P450 oxidoreductase to the reaction mixture containing pancreatic microsomes from the transgenic mice did not increase the estrone metabolism activity significantly. This transgenic mouse line provides another useful tool to study human CYP1A2 and its relation to chemical toxicity and carcinogenesis.

Animals↗
PubMed2000

Synthesis and biological property of carba and 20-deoxo analogues of arenastatin A.

The carba analogue, in which a methylene group is substituted for the oxygen atom linked to C-15, and 20-deoxo analogue of arenastatin A, a potent cytotoxic spongean depsipeptide, were synthesized. Both analogues lacking the 15,20-ester function, which was easily metabolized in serum, showed good stability in serum as well as moderate cytotoxic activity against KB cells and better solubility.

Animals↗
PubMed2000

Cross-protection against a lethal influenza virus infection by DNA vaccine to neuraminidase.

Cross-protection against a lethal influenza virus infection was examined in BALB/c mice immunized with plasmid DNAs encoding the neuraminidase (NA) from different subtype A viruses. Each NA-DNA was administered twice, 3 weeks apart, at the dose of 1 microg per mouse by particle-mediated DNA transfer to the epidermis (gene gun) or at a dose of 30 microg per mouse by electroporation into the muscle. Three weeks after the second vaccination, the mice were challenged with lethal doses of homologous or heterologous viruses and the ability of each NA-DNA to protect the mice from influenza was evaluated by determining the lung virus titers, body weight and survival rates. The H3N2 virus NA-DNA conferred cross-protection against lethal challenge with antigenic variants within the same subtype, but failed to provide protection against infection by a different subtype virus (H1N1). The degree of cross-protection against infection was related to titers of the cross-reacting antibodies. These results suggest that NA-DNA can be used as a vaccine component to provide effective protection against infection not only with homologous virus but also with drift viruses.

Amino Acid Sequence↗