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F Moriyasu

Publications and source records attributed to F Moriyasu.

At least 19 recordsLinked to original sources
PubMed2005

Puncture of solid pancreatic tumors guided by endoscopic ultrasonography: a pilot study series comparing Trucut and 19-gauge and 22-gauge aspiration needles.

BACKGROUND AND STUDY AIMS: The aim of this prospective study was to compare endoscopic ultrasonography-guided Trucut needle biopsy (EUS-TNB) with EUS-guided fine-needle aspiration biopsy (EUS-FNAB) using 19- and 22-gauge needles for biopsy from different sites in patients with solid pancreatic cancers. PATIENTS AND METHODS: Sixteen consecutive patients with masses in the uncinate process (n = 3), the head (n = 5), or the body and tail (n = 8) of the pancreas underwent both EUS-TNB and EUS-FNAB. The specimens obtained were evaluated by histopathological analysis alone RESULTS: Tissue specimens were obtained by Trucut needle, and by 19-gauge and 22-gauge aspiration needles in 69 %, 69 %, and 100 % of patients respectively. Sensitivity for malignancy was 69 % for all needles. Tissue sampling by Trucut and by 19-gauge aspiration needle from masses in the uncinate process was impossible. The sensitivity of the Trucut and 19-gauge aspiration needles was 100 % in the 11 patients with successful procedures. If Trucut or 19-gauge aspiration needles had been used for body and tail masses, and the 22-gauge aspiration needle for masses in the uncinate process and head, the sensitivity for malignancy would have been 81 %. CONCLUSIONS: EUS-TNB allows reliable tissue sampling for the diagnosis of pancreatic masses, but its use is limited to lesions in the body and tail of the pancreas. EUS-FNAB using a 22-gauge needle may be useful for accurate diagnosis in some patients with masses in the uncinate process or the head of the pancreas.

Aged↗
PubMed2001

Proliferation and functional changes of pancreatic gastrin cells in neonatal rat.

INTRODUCTION: Although gastrin cells are not found in the adult pancreas, they are found transiently in the neonatal pancreas. It has been suggested that gastrin may play a role in pancreatic development. However, cell kinetics as well as the fate and the role of gastrin cells are not clear. METHODOLOGY: Proliferation and functional changes of pancreatic gastrin cells in neonatal Wister rats were studied by immunohistochemistry and [(3)H]thymidine autoradiography. RESULTS: Numbers of pancreatic gastrin cells in neonatal rats showed a peak immediately after birth and then decreased rapidly. Gastrin cells were observed within approximately 2 weeks after birth in islets and within approximately 4 weeks after birth among exocrine cells. In contrast with the decrease of gastrin cell numbers, numbers of duodenal cholecystokinin cells increased remarkably after 7 days of age. Proliferative activity of acinar cells showed two peaks at age 2 days and 9 days. Despite a decrease in gastrin cell numbers, gastrin cells maintained a certain degree of proliferative activity. The "re-staining method" for gastrin and insulin revealed that immunoreactive cells for both gastrin and insulin were rarely found a few days after birth. CONCLUSION: These results suggest that pancreatic gastrin cells do not die off or change to another type of endocrine cell and that some gastrin cells change to insulin cells.

Aging↗
PubMed2001

Cisplatin-incorporated polymeric micelles eliminate nephrotoxicity, while maintaining antitumor activity.

cis-Diamminedichloroplatinum (II) (cisplatin, CDDP), a potent anticancer agent, was bound to the aspartic acid residues of poly(ethylene glycol)-poly(aspartic acid) (PEG-P(ASP)) block copolymer by ligand substitution reaction at the platinum atom of CDDP. The polymeric drug thus obtained was observed to form a micelle structure in aqueous medium, showing excellent water solubility. In the present study, in vitro and in vivo antitumor activity against several human tumor cell lines, toxicity and pharmacokinetic characteristics in rodents of CDDP-incorporated polymeric micelles (CDDP / m) were evaluated in comparison with those of CDDP. In vitro, CDDP / m exhibited 10 - 17% of the cytotoxicity of CDDP against human tumor cell lines. CDDP / m given by intravenous (i.v.) injection yielded higher and more sustained serum levels than CDDP. In vivo CDDP / m treatment resulted in higher and more sustained levels in tumor tissue than CDDP, and showed similar antitumor activity to CDDP against MKN 45 human gastric cancer xenograft. CDDP / m treatment caused much less renal damage than CDDP. These results indicate that CDDP / m treatment can reduce CDDP-induced nephrotoxicity without compromising the anticancer cytotoxicity of CDDP.

Animals↗
PubMed2001

Detection of telomerase reverse transcriptase mRNA in biopsy specimens and bile for diagnosis of biliary tract cancers.

Human telomerase reverse transcriptase (hTERT), which codes for the catalytic subunit of telomerase, is essential for telomerase activity. Recent studies revealed that levels of hTERT mRNA as well as telomerase activity are high in neoplasm. The purpose of this study was to correlate the expression of hTERT mRNA with telomerase activity in biopsy specimens and bile from biliary tract cancers and to evaluate the potential diagnostic value of hTERT mRNA analysis for biliary malignancy. We analyzed hTERT mRNA and telomerase activity in biopsy specimens and exfoliated bile cells from patients with cholangiocarcinoma, gallbladder carcinoma and bile duct stones. hTERT was detected by either nested reverse transcriptase-polymerase chain reaction (PCR) or real-time PCR. Telomerase activity was examined by a fluorescence-based telomeric repeat amplification protocol assay. Six of 10 malignant biopsy specimens had detectable hTERT and 7 of 10 had telomerase activity. All cases with hTERT expression had telomerase activity. In bile, 7 of 10 malignant patients had detectable hTERT and 3 of 10 had telomerase activity. Importantly, there were no false positive results in tissue specimens or bile examined in 6 non-cancerous cases. In conclusion, the detection of hTERT mRNA in biopsy specimens and bile cells, in combination with routine histologic and cytologic examination may improve the diagnosis of biliary tract cancers.

Aged↗
PubMed2001

Liver targeting of interferon-beta with a liver-affinity polysaccharide based on metal coordination in mice.

Frequent and high-dose i.v. injections of interferon-beta (IFN-beta) have been used clinically to treat patients with viral hepatitis despite various side effects. Because side effects are caused by the systemic effects of IFN-beta, the purpose of this study was to target the drug specifically to the liver, thus reducing the adverse events. A chelating residue, diethylenetriaminepentaacetic acid (DTPA), was introduced to pullulan, a water-soluble polysaccharide with a high affinity for the liver. Murine IFN-beta could be coordinately conjugated with the DTPA-pullulan by simple mixing in an aqueous solution containing zinc ion (Zn2+). Intravenous injection of the IFN-beta-DTPA-pullulan conjugate with Zn2+ coordination enhanced liver induction of an antiviral enzyme, 2',5'-oligoadenylate synthetase (2-5AS), to a greater extent than that by free IFN-beta, although the 2-5AS levels in the liver depended on the mixing ratio of the IFN-beta/DTPA residue of DTPA-pullulan/Zn2+. In addition, the duration of the liver 2-5AS induction by the IFN-beta-DTPA-pullulan conjugate with Zn2+ coordination was longer than that by free IFN-beta. The liver targeting of IFN-beta by DTPA-pullulan with Zn2+ coordination may be a promising IFN therapy.

Animals↗
PubMed1999

Analysis of flash echo from contrast agent for designing optimal ultrasound diagnostic systems.

Microbubble-based contrast agents can enhance echoes in areas of low blood flow, but the bubbles are extremely sensitive and collapse easily when exposed to ultrasound (US) irradiation. An experimental study of bubble collapse was carried out to design new functions for US diagnostic systems to detect echoes from microbubbles more efficiently. For contrast agent (Levovist) solution, a high-intensity, but momentary, echo (flash echo), was observed in the first frame image after a several-second suspension of transmission, but was not seen in the second frame image. These "flash echo" signals were analyzed and categorized based on microscopic observation, and the results showed that the longevity of the microbubbles was reduced by conditions such as B-mode imaging. Next, a numerical simulation of the bubbles in liquid was performed under the same conditions as in the in vitro experiment. The results showed that even bubbles less than 1 microm in diameter expand and collapse within one pulse drive, which would generate flash echoes. The flash echo imaging system described here permits flexible intermittent scanning with variable intervals, with a variable number of frames at the trigger, and with simultaneous monitoring at low power output. Animal experiments were also conducted to evaluate the system. As the interval between frames was increased, the flash echoes gradually increased, and perfusion in the parenchyma was clearly observed with an interval of 4 s.

Animals↗
PubMed1999

High prevalence of anti-hepatitis B virus serological markers in patients with hepatitis C virus related chronic liver disease in Japan.

BACKGROUND/AIMS: Evidence is accumulating that hepatitis B virus (HBV) is present in patients who are hepatitis B surface antigen negative but have antibody to hepatitis B core antigen (anti-HBc). Furthermore, recent studies have shown that patients with hepatocellular carcinoma who have antibody to hepatitis C virus (HCV) often possess HBV related serological markers. Data on the seroprevalence of HBV infection in patients with HCV related chronic liver disease were collected to evaluate the significance of the presence of antibodies to HBV. METHODS: The prevalence of HBV related serological markers was analysed in a total of 2014 Japanese patients with HCV infection. The control group comprised 352 subjects without liver disorder. RESULTS: A large number of patients (49.9%) with HCV related chronic liver disease including hepatocellular carcinoma were positive for anti-HBc. In addition, the prevalence of anti-HBc closely correlated with the clinical stage of the liver disease. There was no relation between a past history of blood transfusion and the prevalence of anti-HBc. Notably, anti-HBc was the only serological marker for HBV infection in a significant number of patients with HCV related chronic liver disease (24.1%). CONCLUSIONS: Our data provide further evidence for the high prevalence of anti-HBc in patients with HCV related chronic liver disease, particularly those with hepatocellular carcinoma, suggesting that HBV infection, probably including latent infection, may play an important role in carcinogenesis in these patients.

Adult↗
PubMed1999

Ultrasonographic arterial portography with second harmonic imaging: evaluation of hepatic parenchymal enhancement with portal venous flow.

Ultrasonographic arterial portography was evaluated with second harmonic and conventional gray scale imaging after the administration of 0.001 to 0.1 ml/kg of FS069 (Optison) in 10 dogs (four dogs with ligation of the portal vein branch) and two woodchucks with hepatocellular carcinomas. Harmonic imaging was required to obtain good liver parenchymal enhancement for ultrasonographic arterial portography to be useful. The tumors were visible as regions of greater enhancement after intravenous injection and as hypoechoic regions after superior mesenteric artery injection. The segments with portal vein ligation were not detected after intravenous injection but were clearly seen after superior mesenteric artery injection. Doppler signal measurement verified a significant difference between the portal vein and hepatic vein after superior mesenteric artery injection and in the femoral artery after intravenous versus superior mesenteric artery injection, demonstrating that minimal levels of FS069 pass through the liver.

Albumins↗
PubMed1998

Liver-type arginase in serum during and after liver transplantation: a novel index in monitoring conditions of the liver graft and its clinical significance.

We quantified liver-type arginase in sera of 47 patients undergoing partial liver transplantation with use of an ELISA method. The level of liver-type arginase fluctuated slightly beyond the normal range in successful liver recipients, while it changed more drastically or precipitously in unsuccessful ones, accompanying or unaccompanying elevation of AST and ALT levels. A higher elevation pattern of the arginase level (above 100 ng ml-1) was observed in each of the unsuccessful recipients with critical condition, except for one patient. Other hepatic markers (LDH, ALP, and T-BIL) remained relatively unchanged until the terminal stage of deceasing patients. The finding that the liver-type arginase emerged in large quantity in the blood stream immediately after reperfusion of the liver graft indicates that the enzyme leaks out of hepatocytes damaged, presumably, by storage in the absence of circulation. A half-life of the liver-type arginase in the human blood was estimated to be 1 h, that is clearly shorter than that of AST. The short half-life of the arginase appears to be ascribable, at least partly, to formation of an immune complex with circulating autoantibody which appears in many liver recipients. These results suggest that liver-type arginase behaves uniquely in the serum among many hepatic enzymes, and could serve as a distinct marker of hepatic lesions, particularly during and after liver transplantation.

Adolescent↗
PubMed1998

A bioassay for serum interferon based on induction of 2'5'-oligoadenylate synthetase activity.

We have developed a bioassay for interferons (IFN) based on measuring the amounts of 2',5' oligoadenylate synthetase (2-5AS) induced in cells of the THP-1 monocyte line in response to IFN. The assay can be completed in 20 h, gives reproducible results, and is at least 50 times more sensitive to IFN-alpha than conventional cytopathic effect inhibition antiviral assays. It is, respectively, less and much less sensitive to IFN-beta and IFN-gamma. The presence of preexisting 2-5AS activity in a sample does not influence the results. We have used this assay to measure very low levels (0.1-0.5 IU/ml) of endogenously formed IFN-alpha in serum samples from patients with various diseases and also to measure the residual small amounts of IFN-alpha still present in the serum as late as 48 h after an i.m. injection of 3 million IU, which is appreciably later than in previous methods. Thus, our highly sensitive assay offers considerable advantages, not least in relation to the clinical use of IFN.

2',5'-Oligoadenylate Synthetase↗
PubMed1998

Direct measurement of graft and recipient liver fossa size by computed tomography for avoiding problems due [correction of clue] to large graft size in living-related liver transplantation.

We investigated the incidence and manifestation of problems associated with large graft size in living-related liver transplantations and assessed the usefulness of determining volume and dimensions of the graft and recipient's liver fossa by computed tomography to indicate the risk. Five of 150 living related liver transplantations had grafts that were too large, resulting in difficulty in primary abdominal closure or in sudden worsening of hemodynamics during primary closure. No significant difference existed in recipient age, sex, body weight, selection of the graft segment, hepatic vein reconstruction, recipient resected liver weight, graft volumetry value, the ratio of body weight of donor relative to recipient, and the percentage of graft weight relative to recipient body weight, between the groups with and without these problems. Mean +/- SEM of maximal dimensional ratio, defined as the maximum of the ratios of 3 dimensions of the graft relative to recipient liver fossa, were 2.36 +/- 0.64 for patients with grafts that were too large and 1.00 +/- 0.02 for the cases without size problems. The mean +/- SEM of liver fossa index, defined as the product of 3 dimensions of recipient liver fossa, were (25.03 +/- 7.18) x 10(4) mm3 and (127.54 +/- 5.07) x 10(4) mm3, respectively. These two indices clearly indicated the risk of problems due to large graft size, and will help to protect recipients and provide a basis for evaluating graft size in reductions.

Child, Preschool↗
PubMed1998

[Ultrasound contrast agents--newly developed agents and their clinical utility].

Recently many ultrasound contrast agents have been developed. Vascular and parenchymal enhancement of the organs such as liver and myocardium is obtained by intravenous injection of microbubble agents. They can survive after recirculation through the pulmonary capillary beds and under changes in vascular pressure. Several modalities of ultrasound imaging have been developed for effective enhancement. The harmonic imaging system is the most effective to depict contrast enhancement because of subtraction effect using retrieval of harmonic components from interaction microbubbles and ultrasound transmission. This is originated from resonance and destruction of microbubbles under ultrasound exposure.

Contrast Media↗
PubMed1998

[Sonographic depiction of woodchuck hepatomas using intravenously injected contrast agents].

Intravenously injected ultrasonic contrast agents have improved sonographic visualization of blood flow. On enhanced color Doppler sonography using Levovist (Schering AG, Germany) and FS069 (Molecular Biosystems, USA), minute tumor blood flow in woodchuck hepatoma was clearly demonstrated as vascular flow around and within the tumors. Furthermore, on enhanced gray scale sonography using FS069, parenchymal flow was demonstrated as sonographic "tumor stain". However, larger doses of the agent provided shadowing that disturbed sonographic evaluation of deeper portions of the liver. With advances of second harmonic imaging, it may be possible to evaluate only blood perfusion in that it eliminates the signals of fundamental frequency.

Albumins↗
PubMed1998

[Contrast-enhanced power Doppler imaging of the liver--preliminary animal study].

PURPOSE: To evaluate efficacy of contrast-enhanced power Doppler imaging of the liver. MATERIALS AND METHODS: We administered two kinds of contrast agents, SHU-508 (Schering AG, Germany) and FS069 (MBI, USA), intravenously to woodchucks with hepatocellular carcinomas. Power Doppler imaging of the liver was performed. To obtain minute hemodynamic information of the liver, we tried continuous infusion of contrast agents and flash echo mode (intermittent scanning) on power Doppler imaging. RESULTS: When we administered continuously contrast agents, the enhancement increased gradually and lasted until the end of the infusion. To compare with bolus injection, we were able to detect blood flow of the liver more clearly and easily without saturation artifacts. On power Doppler flash echo imaging of three or five seconds suspension, signals from only arterial flow were obtained. In comparison on seven seconds suspension imaging, signals from both arterial and portal flow were obtained. With flash echo mode, we could acquire the information of blood perfusion to depict the signals from eliminated microbubbles. CONCLUSION: With continuous infusion and flash echo mode on contrast-enhanced power Doppler imaging, we could get more detailed information of blood flow and perfusion of the liver. This method is expected to be useful for the diagnosis of liver tumor in clinical settings.

Albumins↗