Biomedical subjects

H Masuko

Publications and source records attributed to H Masuko.

At least 19 recordsLinked to original sources

PubMed2006

[Usefulness of ultrasonically activated scalpel for pulmonary resection in video-assisted thoracoscopic surgery].

We evaluated the reliability and efficacy of the ultrasonically activated scalpel (Harmonic Scalpel) for pulmonary resection in video-assisted thoracoscopic surgery (VATS). Fifty-six cases of primary or metastatic lung cancer with history of lobectomy or segmentectomy from July 2003 to June 2006 were investigated. The ultrasonically activated scalpel was used to separate aborted lobulation and segment in the surgery. The outcome of the operation using the ultrasonically activated scalpel revealed the mean operation time of 224.5 minutes and mean blood loss volume of 116.7 ml. The chest drainage catheter was removed at the postoperative day 3.4 and hospitalization lasted 10.4 days on average. By means of statistical analysis, no significant differences were noted when compared with the cases using surgical stapler to separate the lobules or segments of the lungs. Histopathological results showed destruction of alveolar structures and denaturation of cells at the cut surface of the resected lung through the use of the ultrasonically activated scalpel. This method resulted in good lung expansion and preservation of the residual lung volume. Furthermore, it prevented postoperative air leakage by appropriate treatment to the cut surfaces of the residual lung. Indeed, the method appears to be useful in the separation of lung tissues in severe aborted lobulation and segmentectomy by VATS.

Aged↗

PubMed2001

Protective effect of agiotensin II type I receptor antagonist, CV-11974, on ischemia and reperfusion injury of the liver.

BACKGROUND: Microcirculatory disturbance has been shown to play a critical role in hepatic ischemia and reperfusion (I/R) injury. Angiotensin II (AngII) is one of the most potent endogenous vasoconstrictors. Angiotensin II type I (AT1) receptor antagonist has been reported to have protective effects on I/R injury of the heart and kidney. However, effect on hepatic I/R injury has not been determined. In this study, we investigate our hypothesis that AT1 receptor antagonist, CV-11974, attenuates hepatic I/R injury. METHODS: Twelve beagle dogs underwent a 2-hr total hepatic vascular exclusion with veno-venous bypass. CV-11974 was given to animals at a dose of 0.002 mg/ kg/min for 5 min followed by 0.001 mg/kg/min for 25 min via portal vein before ischemia (group II, n=6). Nontreated animals were used as the control (group I, n=6). Animal survival, hemodynamics, hepatic tissue blood flow (HTBF), liver function, platelet count, renin activity, and AngII concentration of hepatic vein, energy metabolism, and histopathology were analyzed. RESULTS: Two-week survival was 33% in group I, in contrast, 100% in group II. Mean arterial blood pressure during early reperfusion was maintained, and HTBF after reperfusion was significantly higher in group II. Treatment attenuated liver enzyme release and decrease of platelet count, increased renin and AngII, suppressed ATP degradation during ischemia and enhanced ATP resynthesis after reperfusion. Neutrophil infiltration and histopathological damages were lessened in group II. CONCLUSIONS: Our data demonstrated that the local renin-angiotensin system might play a role in hepatic microcirculation. AT1 receptor blockade with CV-11974 attenuated hepatic microcirculatory disturbance and ameliorated I/R injury.

Angiotensin II↗

PubMed2000

Prolongation of canine liver allograft survival by a novel immunosuppressant, FTY720: effect of monotherapy and combined treatment with conventional drugs.

BACKGROUND: The immunosuppressive effect and other properties of a novel immunosuppressant, FTY720, have been studied mostly in the experimental transplantation of various extrahepatic organs. In this experiment, we evaluated the antirejection potency and adverse effects of this agent on liver grafts using a canine liver transplantation model. METHODS: Forty-eight orthotopic liver transplantations were performed by the standard technique under a veno-venous bypass. Liver recipients were divided into two studies: a single-dose study with FTY720 at various doses and a combined dose study with conventional immunosuppressants (cyclosporine or tacrolimus) alone and combined with FTY720. Survival, biochemical and hematological tests, blood levels of immunosuppressants, and postmortem histology were determined. RESULTS: The median survival of untreated control animals was 9 days, whereas treatment with FTY720 at a dose of 0.1 mg/kg/day prolonged graft survival to 49.5 days. FTY720 at 1 mg/kg/day showed a slight but insignificant prolongation to 16 days, but when the dose was increased to 5 mg/kg/day, the graft was rejected at 10 days. The combination of FTY720, 0.1 mg/kg/day, with a subtherapeutic dose of cyclosporine, 5 mg/kg/ day, prolonged median animal survival from 40 days with cyclosporine alone to 74 days. A combination of FTY720 (0.1 mg/kg/day) with tacrolimus (0.5 mg/kg/ day) compromised animal survival, reducing survival from 83.5 days with tacrolimus alone to 30.5 days due to infectious complication and emaciation by overimmunosuppression. No evident drug-induced side effects were observed. CONCLUSIONS: FTY720 has a potent immunosuppressive effect when used alone at 0.1 mg/kg/day in canine liver transplantation. FTY720 is a promising candidate for future clinical application in orthotopic liver transplantation.

Animals↗

PubMed1997

The role of magnetic resonance cholangiopancreatography (MRCP) after resection of the pancreas.

Magnetic resonance cholangiopancreatography (MRCP) was performed in 35 patients to evaluate the feasibility of its use as a postsurgical imaging technique after resection of the pancreas. The surgical procedures performed were: pancreatoduodenectomy in 22 patients, segmental pancreatectomy in 1, distal pancreatectomy in 7, and pyrolus-preserving pancreatoduodenectomy in 5. The pancreatic duct was shown in its entirety in 24 of the 35 patients (68.6%) and was partially visualized in 8 patients (22.9%), but the intrahepatic and extrahepatic bile ducts were visualized completely in all patients. Furthermore, MRCP was able to demonstrate lesions in 3 of 6 patients who had shown clinical evidence of recurrence. The visualization of the pancreatic and bile duct system was satisfactory despite anatomical changes brought about by resection of the pancreas. Thus, we conclude that MRCP is an appropriate follow-up screening test for patients with suspected abnormalities of the biliary and pancreatic duct system.

Aged↗

PubMed1992

An immunoenzymometric assay for a CA125-like antigen, CA602.

An immunoenzymometric assay (IEMA) for a new CA125-like antigen, CA602, was developed. Five monoclonal antibodies raised against a human ovarian carcinoma cell line could detect their respective antigens in the sera of ovarian carcinoma patients. The antigen levels detected in serum by the various antibodies correlated significantly to each other, and to CA125 levels. The results of epitope analyses and combined IEMAs suggested that the epitopes recognized by these antibodies are not same, but exist on the same antigen which bears the CA125 epitope. A sensitive IEMA was developed with 602-1 and 602-6 antibodies which showed high reactivity to the CA125-like antigen. The antigen defined by these two antibodies was designated as CA602, and serum CA602 levels correlated well with CA125 levels. The CA602 antigen is a CA125-like antigen. Furthermore, the serum CA602 levels did not correlate to CA54/61 levels. The combined assays of CA602 and CA54/61 may increase the detection of ovarian carcinoma.

Antigens, Tumor-Associated, Carbohydrate↗

PubMed1992

Specificity of a tumor marker (CA54/61) and its individual epitopes recognized by monoclonal antibodies, MA54 and MA61, in human tumor patients.

The specificity of a tumor marker (CA54/61) and its individual epitopes (CA54 and CA61) recognized by monoclonal antibodies (MA54 and MA61) and expressed by the same tumor marker were studied. Serum levels of CA54 and CA61 were compared with that of CA54/61. In lung adenocarcinoma and ovarian carcinoma, the positive rates of CA61 (42% and 68%) were higher than those of CA54 (32% and 32%) and similar to those of CA54/61 (45% and 74%). The serum levels of CA54 and CA61 showed a significant correlation (r = 0.78), but 22% of tested sera were positive for CA54 and negative for CA61 or negative for CA54 and positive for CA61. It was demonstrated that the tumor specificity between CA54 and CA61 was not same and that the tumor specificity of CA54/61 was similar to that of CA61 rather than CA54. Moreover, the difference in the tumor specificity between CA54 and CA61 was considered to be reflected in the difference in their epitope structure.

Antibodies, Monoclonal↗

PubMed1992

[A study of urinary tegafur, 5-fluorouracil (5-FU) and uracil concentrations in the cases of gastric carcinoma for the confirmation of drug-taking compliance after UFT oral administration].

We have measured urinary tegafur (FT), 5-FU and uracil concentrations after UFT oral administration (300 mg daily for 7 days) to confirm drug-taking compliance in the 17 cases undergone gastrectomy. Urinary FT and 5-FU concentrations reached to the plateau 2 and 3 days after administration, respectively, and were maintained until the day after termination of administration. Subsequently, FT and 5-FU concentrations also decreased about 50% at 2 day, 20% at 3 day, 10% of the plateau values at 4 day after termination, respectively. The mean plateau value of urinary FT was 12.9 +/- 6.8 micrograms/dl, and that of urinary 5-FU was 0.67 +/- 0.50 microgram/dl. On the other hand, uracil concentration, was not different before and after administration because of the uracil being present endogenously. Therefore, it was suggested that measurement of urinary FT and 5-FU concentrations is useful for confirmation of UFT-taking compliance.

Administration, Oral↗

PubMed1992

Platelet-derived growth factor and growth-promoting activity in the serum samples and platelets of patients with non-insulin-dependent diabetes mellitus.

Although platelet-derived growth factor (PDGF) is thought to be a major mediator of atherosclerotic disease, the pathophysiology of diabetic vasculopathy, including atherosclerosis, is unclear. By means of an enzyme immunoassay that used a monoclonal antibody against human PDGF-B chain, PDGF-like immunoreactivity was determined in serum, platelet-poor plasma, and platelet lysate of 28 patients with non-insulin-dependent diabetes mellitus and 11 control subjects. Growth-promoting activity was also measured by tritiated thymidine incorporation into DNA of cultured human fibroblasts. The PDGF-like immunoreactivity in serum was correlated (r = 0.42; p less than 0.01) with that in platelet lysate prepared from a fixed volume of blood. Furthermore, a correlation (r = 0.70; p less than 0.001) was found between the PDGF-like immunoreactivity and the growth-promoting activity in platelet lysate but not in serum. There was no significant difference between patients with diabetes and control subjects with respect to the PDGF-like immunoreactivity in serum or in platelet lysate (38.2 +/- 2.2 vs 42.8 +/- 3.1 ng/ml or 49.1 +/- 2.4 vs 56.2 +/- 3.4 ng/mg protein; mean +/- SEM). In contrast, the serum growth-promoting activity was lower (p less than 0.05) in patients with diabetes than in control subjects (88.1% +/- 7.1% vs 117.4% +/- 6.9%) and there was a negative correlation (r = -0.39; p less than 0.05) between the serum growth-promoting activity and the fasting plasma glucose level. The growth-promoting activity in platelet lysate of patients with diabetes did not differ from that of the control subjects (59.9% +/- 11.6% vs 65.9% +/- 11.2%).(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Platelets↗

PubMed1990

Localization of PDGF-B protein in macrophages in all phases of atherogenesis.

Lesions of atherosclerosis occur in the innermost layer of the artery wall and consist primarily of proliferated smooth muscle cells surrounded by large amounts of connective tissue, numerous lipid-laden macrophages, and varying numbers of lymphocytes. Growth-regulatory molecules may be involved in intimal accumulation and proliferation of smooth muscle cells responsible for the occlusive lesions of atherosclerosis. Platelet-derived growth factor (PDGF) B-chain protein was found within macrophages in all stages of lesion development in both human and nonhuman primate atherosclerosis. Thus macrophages may play a critical role in the disease by providing PDGF, a potent chemotactic and growth-stimulatory molecule, to the intimal smooth muscle cells.

Animals↗

PubMed1987