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Biomedical subjects

H Saisho

Publications and source records attributed to H Saisho.

At least 73 records · Page 4Linked to original sources

Quantitative evaluation of telomerase activity in small liver tumors: analysis of ultrasonography-guided liver biopsy specimens.

BACKGROUND/AIMS: Telomerase activity which restores the length of telomere repeat arrays is frequently detectable in various malignancies, including hepatocellular carcinoma. The aim of this study was to determine the diagnostic usefulness of the quantitative measurement of telomerase activity in small liver tumors, which has not yet been established. METHODS: Fifty-eight liver specimens from tumorous and non-tumorous portions of 29 small liver tumors equal to or less than 3.0 cm were obtained by ultrasonography-guided liver biopsy, and of these, 25 were diagnosed as hepatocellular carcinoma and four as adenomatous hyperplasia. The telomerase activities in these specimens and control specimens were examined quantitatively by telomeric repeat amplification protocol with standard control. RESULTS: The mean telomerase activity in cirrhosis without liver tumor was 0.4+/-0.6 (+/-S.D.) arbitrary units (AU) and that in 29 non-tumorous parts of the tumors was 4.5+/-7.4 AU. The mean telomerase activity in 13 tumors equal to or less than 2 cm in diameter was 77.1+/-133.7 AU and that in 16 tumors more than 2 cm was 152.7+/-215.2 AU. The mean telomerase activity in the 4 adenomatous hyperplasias was 5.5+/-4.5 AU; those of hepatocellular carcinoma with Edmondson-Steiner classification I, II, III and IV were 49.6+/-47.4 (n = 10), 240.1+/-273.6 (n = 9), 119.2+/-174.6 (n = 4) and 144.6+/-80.2 (n = 2) AU, respectively. CONCLUSIONS: The telomerase activity was significantly higher in hepatocellular carcinoma compared to adenomatous hyperplasia and non-neoplastic tissue, indicating that the quantitation of telomerase activity would be useful for the diagnosis of small hepatocellular carcinoma.

Adenoma↗

Parenchymal echo patterns of cirrhotic liver analysed with a neural network for risk of hepatocellular carcinoma.

BACKGROUND: To objectively evaluate the parenchymal echo patterns of the liver in cirrhosis, an image analysing system in which a neural network is used has been found capable of numerically calculating coarse score (CS). Using this system, we analysed whether or not CS can serve as a predictive factor for the development of hepatocellular carcinoma (HCC). METHODS: The risk factors for HCC were evaluated in 95 patients with liver cirrhosis with an average follow-up period of 2041 +/- 823 days. We used a three-layer feed-forward neural network and a back-propagation algorithm to calculate CS. RESULTS: There were strong correlations between CS, alanine aminotransferase (ALT) and alpha-fetoprotein (AFP) and the average cumulative incidence rate of HCC evaluated by the Cox's proportional hazards model. The adjusted rate ratios were estimated to be 3.00, 2.80 and 2.01, respectively. The cumulative risks of HCC were significantly higher with an initial CS > or = 1.5 than with an initial CS < 1.5, with ALT > or = 80 IU/L than with initial ALT < 80 IU/L and with AFP > or = 20 ng/mL than with initial AFP < 20 ng/mL, all analysed by the log-rank test. CONCLUSIONS: Coarse score is a useful predictor for development of HCC.

Adult↗

Flow-through thin latissimus dorsi perforator flap for repair of soft-tissue defects in the legs.

Flow-through thin latissimus dorsi perforator flaps were used in six cases with complicated defects of the legs. This flap has a small amount of latissimus dorsi muscle with a considerable amount of fatty tissue removed to make a thin flap. In addition, the flap has several branches of the subscapular vessel, which are interposed to the recipient vessels of the legs. The advantages of this thin flap are: (1) flow-through vascular reconstruction can preserve the main vessels of the damaged legs; (2) the double arterial inflows and venous drainage systems of the flap ensure safe vascularization of the flap; (3) a flow-through venous drainage system from the distal extremities can also be established to prevent congestion of the affected legs; (4) this flap is versatile (it can be either thin or large); and (5) even in emergent ischemic legs, simultaneous elevation of the flap is possible with preparation of the legs. This flow-through flap is indicated for: (1) cases with a large skin defect and obstruction of the main vessels in the leg; (2) cases with a possibility of tumor recurrence in the legs; and (3) young women or girls with a large defect in the legs, rather than the rectus abdominis musculocutaneous flap.

Adult↗

Small hepatocellular carcinoma: relationship of signal intensity to histopathologic findings and metal content of the tumor and surrounding hepatic parenchyma.

PURPOSE: To investigate the relationship between the metal content of hepatocellular carcinoma (HCC) and the signal intensity pattern on magnetic resonance images. MATERIALS AND METHODS: The signal intensity patterns of 59 HCCs 3 cm in diameter or smaller were correlated with histologic findings and metal content. RESULTS: HCCs with high signal intensity on T1-weighted images demonstrated more steatosis (P = .035) and higher copper content (P = .008) than did surrounding hepatic parenchyma. HCCs with high signal intensity on T2-weighted images demonstrated more clear cells (P = .001) than did surrounding hepatic parenchyma. The higher signal intensities on T1-weighted and T2-weighted images were related to a higher and a lower degree of histologic differentiation, respectively. Multivariate analysis showed that the contrast-to-noise ratio between the HCC and surrounding hepatic parenchyma was affected by intratumoral copper content (P = .0338), zinc content of surrounding hepatic parenchyma (P = .0379), and the degree of histologic differentiation on T1-weighted (P = .0031) and T2-weighted (P = .0062) images. CONCLUSION: The signal intensity of HCC on T1-weighted images is related to the degree of histologic differentiation, intratumoral copper content, and zinc content of surrounding hepatic parenchyma, whereas the signal intensity on T2-weighted images is related to the degree of histologic differentiation.

Adult↗

Detection of mutations in the enhancer 2/core promoter region of hepatitis B virus in patients with chronic hepatitis B virus infection: comparison with mutations in precore and core regions in relation to clinical status.

To investigate the meaning of the mutations in the enhancer 2/core promoter (Enh2/CP) region of hepatitis B virus (HBV) during the chronic HBV infection, mutations were examined in the Enh2/ CP region (carboxyl half of X region) and their correlation with mutations in the precore and core regions in relation to the presence of chronic liver disease. The entire nucleotide sequences of the Enh2/CP region were determined by direct sequencing of the amplified products derived from 30 cases with chronic HBV infection. The results were compared to the mutations in the precore and core regions. In the Enh2/CP region, 91 generally scattered nucleotide substitutions were detected. There were 11 substitutions in the 10 asymptomatic healthy carriers (mean, 1.1/case) and 80 in the 20 chronic liver disease patients (4.0/case). The most frequent substitutions from A to T at nucleotide 1764 and from G to A at nucleotide 1766 were seen in none of the 10 asymptomatic carriers and in 14 (70%) of the 20 chronic liver disease patients. Comparisons of mutations in the precore and core regions revealed that 14 of 16 patients with mutations in the core region had the mutations in the Enh2/CP region and/or a precore stop codon mutation. These data suggest that mutations in the Enh2/CP and precore regions may affect the expression of the core and HBeAg peptides and might be involved in the pathogenesis of chronic liver disease.

Adolescent↗

Radiotherapy for large hepatocellular carcinoma combined with transcatheter arterial embolization and percutaneous ethanol injection therapy.

This study was performed to determine the effect of radiotherapy (RT) combined with transcatheter arterial embolization (TAE) and percutaneous ethanol injection (PEI) on large HCC. Between 1988 and 1996, 102 patients with unresectable, biopsy proven HCC underwent uniform pretreatment assessment followed by TAE and PEI. Of the 102 patients, 68 (67%) had more than 2 lesions in the liver, and the largest tumor sizes in each patient ranged from 3 to 8 cm in diameter. Immediately after TAE and PEI, external beam RT (36 to 70 Gy) was administered to the largest tumors only in 44 patients. The cause-specific 5-year survival rate for all patients was 39.9%. The 3-year survival rate of the RT group was better than that of the no RT group (81.1% vs. 54.6%). The cumulative local control rates of the largest treated tumors were 53.2% in the RT group and 32.7% in the no RT, respectively (p=0.006). When the survival rate was compared between patients with and without local control in the RT group, that of patients with local control was significantly better than that with local recurrences (p=0.048). No deaths or major treatment related complications occurred. RT combined with TAE and PEI did not clearly show improvement of the survival, however, it effectively controlled large HCC, and demonstrated minimal toxicity. This treatment may represent therapeutic option for some patients with unresectable large HCC.

Aged↗

[Molecular mechanism of hepatocarcinogenesis].

Hepatocellular carcinoma (HCC) in Japan is closely associated with the chronic liver diseases of infection with the hepatitis B or C viruses. Analysis of HCC tissues frequently detects loss of heterozygosity at chromosomes 1p, 4, 6q, 8p, 10q, 13q, 16q, 17p, and many genomic and epigenomic abnormalities have been found in p53, beta-catenin, p16CDKI, DNA mismatch repair genes, and others. However, no specific abnormal genetic or epigenetic changes for HCC have been found so far. The development of HCC has been reported in mice transgenic for the hepatitis B virus X gene or the hepatitis C virus core gene, and these viral proteins might play essential roles in hepatocarcinogenesis. Chronic hepatitis and fibrosis due to persistent viral infection might also influence the genomic instability of hepatocytes, leading to accumulation of genomic changes.

Animals↗

Loss of tumorigenicity of human pancreatic carcinoma cells engineered to produce interleukin-2 or interleukin-4 in nude mice: a potentiality for cancer gene therapy.

To examine the possibility of cytokine gene therapy in relation to pancreatic cancer, we evaluated the antitumor effect of human pancreatic carcinoma cells (AsPC-1) which were retrovirally-transduced with several kinds of cytokine genes. These cells were inoculated into BALB/c nude mice and their tumor volumes were assessed. The in vitro growth rate of the transduced cells was not different from that of a parental cell line. Among the transduced cells, human interleukin (IL)-6-transduced AsPC-1 and mouse granulocyte macrophage colony-stimulating factor-transduced AsPC-1 cells showed a significant retardation of tumor growth compared with a parental cell line. In the cases of AsPC-1 cells transduced with the human IL-2 or mouse IL-4 gene, small tumors were generated but thereafter they regressed completely. Histological examinations showed monocytic cell infiltration around the tumors of IL-2- or IL-4-producing cells. These data suggest that secretion of IL-2 or IL-4 from tumor cells can induce an antitumor effect even in the defective condition of mature T cells.

Animals↗

XAFS spectra from reflectivity measurements.

The reflectivity of TiSi(2) films was measured as a function of photon energy E at the Ti K-edge region at a glancing angle theta close to the critical angle theta(C) of total reflection. TiSi(2) silicide films (about 30 nm thickness) were prepared by silicidation of Ti thin films deposited on Si(001) substrates. Since the Fresnel reflectivity R(theta,E) is a function of the dispersion delta(E) and of the absorption beta(E), the absorption beta(E) which carries the XAFS signal can be solved as beta(theta,delta,R) for observed reflectivity R and for estimated delta. The dispersion delta(E) is related to the absorption beta(E) by the Kramers-Kronig (K-K) relations since the refractive index is n(E) = 1 - delta(E) - ibeta(E). beta(E) was calculated from the observed reflectivity R(theta,E) using theoretical values for initial delta(E). Titanium K-edge XAFS for TiSi(2) was extracted from the reflectivity by 'ReflXAFS'.

Journal Article↗

Compact superconducting ring at ritsumeikan university.

A compact superconducting storage ring (0.575 GeV and 300 mA) with a racetrack microtron injection system was installed at Ritsumeikan University and has been operated successfully since April 1996. As the radius of the circular electron orbit is small (0.5 m), it is possible to use a radiation beam of relatively high photon flux at a short distance from the source point. Beamlines have been constructed including those for XAFS, soft X-ray spectroscopy, VUV spectroscopy, fluorescent X-ray analysis, soft X-ray microscopy, X-ray diffraction/scattering and photoelectron spectroscopy; the photoelectron spectrometer is combined with an ion-beam-scattering spectrometer to obtain information both on the electronic states and on the atomic arrangements of a solid surface. In addition there are two beamlines, one for LIGA exposure and the other for synchrotron radiation ablation, which are devoted to producing new devices and materials. The synchrotron radiation facility is open not only to users in the University but also to researchers in industry, governmental institutions and other universities.

Journal Article↗

Application of synchrotron radiation in investigation of metal-ion release from a hip replacement prosthesis.

The aim of the present study was to measure very low concentrations of Al, V, Fe, Cr and other metal elements in a matrix of P, S, Cl, Ca and other constituent elements of the human body. These metal elements were released from a failed total hip replacement prosthesis into the surrounding tissues. The experimental results have been compared with those from proton-induced X-ray emission spectroscopy of the same specimen.

Journal Article↗

Significance of parathyroid hormone-related protein as a factor stimulating bone resorption and causing hypercalcemia in myeloma.

Elevated levels of parathyroid hormone-related protein (PTHrP) in hypercalcemic myeloma patients were demonstrated in recent reports, suggesting that PTHrP behaves as a humoral mediator of hypercalcemia in myeloma. Herein we describe a hypercalcemic myeloma patient with a high serum PTHrP level. Moreover, the PTHrP level in the supernatant of bone marrow aspirates was about two-fold of that in serum. Reverve transcriptase-polymerase chain reaction analysis showed PTHrP m-RNA in bone marrow containing myeloma cells. After chemotherapy, the concentrations of calcium and PTHrP decreased and PTHrP mRNA in bone marrow became undetectable. We conclude that PTHrP released by myeloma cells acted as the main bone resorption stimulating factor in this case.

Aged↗

White ball appearance in endoscopic ligation of bleeding esophageal varices.

BACKGROUND: Endoscopic variceal ligation is useful in the control of bleeding from esophageal varices. However, confirmation of ligation precisely at the site of bleeding is usually difficult when treating massive variceal bleeding. Characteristic endoscopic findings that appeared when ligation was performed at the site of bleeding are reported in this article. METHODS: Emergency endoscopic variceal ligation was performed in 14 patients with active bleeding from esophageal varices. Endoscopic findings after variceal ligation at the site of bleeding were compared with those at sites without bleeding. RESULTS: Active bleeding ceased just after endoscopic ligation at the site of bleeding in all patients. After ligation of the bleeding site of the varix, an unusual white-colored ball-like appearance (white ball appearance) was observed in all patients. This finding was markedly different from the purple-colored ball-like appearance that is usually observed after ligation of a varix at a site without bleeding. CONCLUSIONS: White ball appearance was a characteristic finding that appeared after ligation of a varix at the site of bleeding. This finding may be useful in the confirmation of successful ligation of a varix at its bleeding site.

Emergency Treatment↗

Quantitative analysis of GBV-C RNA in liver and serum by strand-specific reverse transcription-polymerase chain reaction.

BACKGROUND/AIMS: Although GB virus C (GBV-C) is frequently detectable in patients with liver diseases, it is not known whether it actually replicates in the liver. Therefore we have quantitatively examined the strand-specific RNA of this virus. METHODS: Fourteen patients (two GBV-C RNA only seropositive, seven both GBV-C RNA and HCV RNA seropositive, and five HCV RNA only seropositive) were examined. Extracted RNAs from sera and liver specimens of these patients were serially diluted and strand-specific RNAs of GBV-C and HCV were quantitatively measured using strand-specific primers by reverse transcription-polymerase chain reaction. RESULTS: Positive-strand GBV-C RNA in serum was detected in all nine GBV-C RNA seropositive cases, and negative-strand RNA was detected in three, uncertain in three, and undetected in three. Positive-strand GBV-C RNA in the liver was detected in seven and undetected in two, while negative-strand RNA in the liver was undetected in eight and uncertain in one. On the other hand, positive-strand HCV RNA was detected in serum from all 12 HCV RNA seropositive patients and negative-strand HCV RNA was detected in one, uncertain in seven, and undetected in four. Positive-strand HCV RNA was detected in the liver from all 12 HCV RNA seropositive patients, and the presence of negative-strand HCV RNA in the liver was confirmed in 10 and uncertain in the remaining two. CONCLUSION: GBV-C is considered to be far less hepatotropic than HCV, and it is suggested that GBV-C might not be replicating in the liver.

Adult↗

Establishment of novel cell lines derived from two patients with chronic myelogenous leukemia in blast crisis; IMS-BC1 and IMS-BC2 which exhibit markedly different sensitivity to apoptosis.

We established two novel cell lines, designated as IMS-BC1 and IMS-BC2, from two patients with chronic myelogenous leukemia in blast crisis. The two cell lines were positive for CD13 and CD33 and negative for CD34 and HLA-DR by surface marker analysis. IMS-BC1 had four Philadelphia (Ph1) chromosomes and a breakpoint within the 3'-portion of M-bcr, and IMS-BC2 had five Ph1 chromosomes and two breakpoints within the 3'- and 5'-portions of M-bcr. Both cell lines' growth activities were moderately suppressed by IFN-alpha. The proliferation of IMS-BC2 was inhibited by IFN-gamma and apoptosis was induced within 72 h, while IMS-BC1 was resistant to IFN-gamma. Fibronectin inhibited the proliferation of the two cell lines at higher than 10 micrograms/ml, but only IMS-BC2 showed apoptosis. Transforming growth factor-beta inhibited the proliferation of IMS-BC2 resulting in apoptosis, while it inhibited that of IMS-BC1 moderately but failed to induce apoptosis. All-trans retinoic acid (ATRA) inhibited the proliferation of IMS-BC2 at very low concentration (10(-17) mol/l) and induced apoptosis at doses higher than 10(-9) mol/l within 72 h without terminal differentiation, while IMS-BC1 was completely resistant to ATRA. The two cell lines showed different responses to growth inhibitory cytokines and factors. These cell lines should prove useful in the analysis of mechanisms of apoptosis induced by growth inhibitory cytokines and factors.

Adolescent↗