Biomedical subjects

H Honda

Publications and source records attributed to H Honda.

At least 19 recordsLinked to original sources

PubMed2002

A porcine coronary stent model of increased neointima formation in the left anterior descending coronary artery.

BACKGROUND: Clinical trials suggest an increased frequency of restenosis after coronary intervention in left anterior descending (LAD) compared to the left circumflex or right coronary arteries. Experimental studies correlate stent-induced arterial injury and the extent of neointima formation. This study investigates whether the coronary artery affects the relationship between arterial injury and neointima hyperplasia in the porcine stent model. METHODS: Non-lipemic farm pigs underwent stent placement in the LAD (n = 26) and the right coronary artery (RCA; n = 30). Quantitative coronary angiography (QCA) was performed before and after stent placement, and at follow-up; quantitative histomorphometry and injury score were analyzed at 30-day follow-up. RESULTS: Initial procedure balloon/artery ratios (LAD 1.17 +/- 0.11 vs RCA 1.17 +/- 0.09, P = NS), and minimal stent lumen diameters (MLD; LAD 2.91 +/- 0.31 vs RCA: 2.93 +/- 0.28 mm, P = NS) were similar suggesting no difference in deployment technique. At follow-up there was more restenosis in the LAD (diameter stenosis: 55.0 +/- 26.4% vs 37.3 +/- 18.1%, and MLD: 1.24 +/- 0.78 mm vs. 1.71 +/- 0.57 mm, P < 0.05 for both comparisons). No differences were seen for injury score (1.09 +/- 0.51 vs 1.01 +/- 0.57; LAD vs RCA) or stent area (6.13 +/- 0.99 vs 6.55 +/- 1.42 mm2). Histomorphometry demonstrated smaller lumen area (2.15 +/- 0.94 vs 2.96 +/- 1.29 mm2) and thicker neointima (0.63 +/- 0.25 vs 0.51 +/- 0.17 mm; all P < 0.05) in the LAD. Multiple linear regression analysis identified the LAD as an independent predictive factor for increased neointima formation. CONCLUSIONS: These observations establish an animal model that is consistent with clinical experience showing that restenosis after stenting is more common in the LAD. The findings may be useful for understanding and developing systemic and local antirestenotic strategies.

Angioplasty, Balloon, Coronary↗

PubMed2002

Autonomic nervous activity before and after eradication of Helicobacter pylori in patients with chronic duodenal ulcer.

BACKGROUND: Helicobacter pylori infection is involved in the formation of chronic peptic ulcer. However, a previously reported hypothesis concerning the involvement of central autonomic nervous disorder in this condition cannot be ruled out. AIM: To use spectrum analysis of heart rate viability to examine autonomic nervous activity before and after H. pylori eradication. METHODS: Twenty patients with chronic duodenal ulcer (duodenal ulcer group) and 20 age-matched normal adults (N group). In both groups, 24-h Holter electrocardiograms (ECGs) were recorded and spectrum analysis of heartrate variability was performed. In the duodenal ulcer group, Holter ECG was recorded before and after H. pylori eradication. RESULTS: In the N group, analysis of heart rate variability showed that high frequency (HF) power, an index of parasympathetic activity, was high at night, while the low frequency (LF)/HF ratio, an index of sympathetic function, was high during the daytime. In the duodenal ulcer group, HF power was higher at night than during the daytime, showing a similar pattern to the N group, but the power value was higher than in the N group (P < 0.05). In the duodenal ulcer group, LF/HF at night was significantly higher than that of the N group. In addition, in the duodenal ulcer group, autonomic activity after H. pylori eradication did not differ significantly from that before H. pylori eradication. CONCLUSIONS: In patients with chronic peptic ulcer, both sympatheticotonia and parasympatheticotonia may occur at night, and this abnormality in autonomic nervous activity may cause increased gastric acid secretion and gastric mucosal vasoconstriction. Abnormalities in autonomic activity persist even after H. pylori eradication, suggesting that they may be an independent risk factor in the formation of chronic peptic ulcer in addition to H. pylori infection.

Autonomic Nervous System Diseases↗

PubMed2002

A case of lupus nephritis with alteration of the glomerular basement membrane associated with Takayasu's arteritis.

A 47-year-old Japanese woman with both Takayasu's arteritis (TA) and systemic lupus erythematosus (SLE) presented with unequal pulses in the upper extremities, diarrhea and proteinuria. In 1986, when she was 38 years old, angiography revealed stenosis of the left subclavian artery. In 1994, SLE was diagnosed on the basis of clinical and laboratory findings, including renal dysfunction, hematologic and immunologic abnormalities, a high titer of antinuclear antibody and a positive lupus band test on the skin. Renal biopsy showed lupus nephritis and glomerular lesions with a bubble-like appearance of the glomerular capillary wall with TA. Lupus nephritis coexisting with glomerulonephropathy associated with TA has rarely been reported.

Basement Membrane↗

PubMed2001

Beneficial effects of 3-dimensional visualization on hepatic vein reconstruction in living donor liver transplantation using right lobe graft.

BACKGROUND: Recently, virtual operation planning and navigation systems have been introduced in the field of neurosurgery and orthopedic surgery. We report here the beneficial effects of 3-dimensional (3D) visualization on hepatic venous reconstruction in living donor liver transplantation (LDLT) using right lobe graft. METHODS: 3D-image reconstruction of the liver was rendered with 3-mm slices of helical computed tomography (CT) data using zioM900 (Zio Software Inc., Tokyo, Japan). To understand the anatomy of the donor's vessels and design an operation plan, a picture of the vessels in and around the liver was reconstructed. RESULTS: The 3D image demonstrated two short hepatic veins next to the inferior right hepatic vein (IRHV) as well as a large IRHV. The 3D image showed a more precise diameter of the right hepatic vein (RHV) and the IRHV and a more accurate distance between the two hepatic veins than did images measured by 2-dimensional CT. This preoperative information allowed the donor surgeon to dissect the inferior vena cava (IVC) and hepatic veins with reduced blood loss because of reduced risk of injury to the blood vessels. The 3D image revealed that both the RHV and the IRHV branched off at the same angle from the cylindrical IVC. Preoperative planning based on this information secured smooth anastomosis. CONCLUSIONS: 3D visualization is useful for hepatic venous reconstruction of the recipient as well as for donor surgery in LDLT using right lobe graft.

Female↗

PubMed2001

Hepatic stellate cells contain the functional estrogen receptor beta but not the estrogen receptor alpha in male and female rats.

In an earlier study, we showed that estradiol (E2) inhibits proliferation and transformation in cultured rat hepatic stellate cells (HSCs) and that the actions of E2 are mediated through estrogen receptors (ERs). This study reports on an investigation of the cellular localization of ER subtypes ERalpha and ERbeta using immunohistochemistry in experimental fibrotic liver rats and of each ER subtype expression in cultured rat HSCs by evaluating the produced mRNA and protein. The results indicate that high levels of ERbeta expression and low or no levels of ERalpha expression were observed in normal and fibrotic livers and in quiescent and activated HSCs from both males and females. The specificity of E2-mediated antiapoptotic induction through the ERbeta was shown by dose-dependent inhibition by the pure ER antagonist ICI 182,780 in HSCs which were undergoing early apoptosis. These findings demonstrate for the first time that rat HSCs possess functional Erbeta, but not Eralpha, to respond directly to E2 exposure.

Animals↗

PubMed2001

Possible mechanisms for the suppressing action of 17beta-estradiol on beta-adrenoceptor-mediated vasorelaxation in rat aorta.

The mode of action of estrogen on beta-adrenoceptor-mediated relaxation was investigated by using isolated ring preparations of thoracic aorta from ovariectomized rats. Administration of 17beta-estradiol to ovariectomized rats significantly suppressed isoprenaline-induced relaxation of aortic rings. There was no alteration in the beta-adrenoceptor binding characteristics. The suppressing action of 17beta-estradiol on the N(G)-nitro-L-arginine and indomethacin-resistant relaxation induced by isoprenaline disappeared after pretreatment with N,N-diethylaminoethyl-2,2-diphenylvalerate hydrochloride (SKF 525A), an inhibitor of cytochrome P450 (CYP). The levels of CYP2C11 expression were the highest of the CYP mRNAs examined in rat aorta. 17beta-Estradiol replacement increased the expression of CYP2C11 mRNA in the aorta, compared with that in ovariectomized rats. These results suggest that estrogen suppresses beta-adrenoceptor-mediated vasorelaxation, and that the mechanisms may be associated with alterations in CYP2C11 metabolites.

Adrenergic beta-Agonists↗

PubMed2001

Liver metastasis from gallbladder carcinoma: anatomic correlation with cholecystic venous drainage demonstrated by helical computed tomography during injection of contrast medium in the cholecystic artery.

BACKGROUND: The current study evaluated whether the sites of liver metastasis from gallbladder carcinoma are correlated with areas of cholecystic venous drainage (CVD) utilizing helical computed tomography (CT) during the injection of contrast medium into the cholecystic artery (cholecystic artery CT). METHODS: Cholecystic artery CT scans were performed in 26 patients with gallbladder carcinoma. Liver metastases were examined retrospectively in these patients on CT, and the sites of liver metastasis and CVD were compared closely. The patients were divided into concurrent (those who had metastasis at the time of cholecystic artery CT), early postoperative metastasis (those who developed metastasis within 6 months after surgery), and late postoperative metastasis (those who developed metastasis more than 6 months after surgery) groups. The frequency of metastasis related to CVD was compared between the three groups. RESULTS: A total of 32 metastases were identified in 11 patients, 21 of which were related to CVD. Six patients were included in the concurrent metastasis group; 18 of 20 tumors were found to be related closely to CVD. There were two patients in the early postoperative metastasis group; all three of the tumors detected were found to be closely related to CVD. Three patients were subclassified as being in the late postoperative metastasis group; none of the nine tumors detected appeared to be in areas associated with CVD. CONCLUSIONS: The sites of liver metastases were found to be well correlated with the areas with CVD, particularly in the concurrent and early postoperative metastasis groups. CVD may be a useful marker of potential areas of liver metastasis from gallbladder carcinoma, particularly in patients with early stage metastasis.

Adult↗

PubMed2001

Elevated expression of UDP-N-acetylglucosamine: alphamannoside beta1,6 N-acetylglucosaminyltransferase is an early event in hepatocarcinogenesis.

Previous reports have suggested that changes in oligosaccharide structures, especially beta1-6 branching in N-glycans, which are biosynthesized by UDP-N-acetylglucosamine:alpha mannoside beta1,6 N-acetylglucosaminyltransferase (GnT-V), are linked to tumor metastasis and invasion. In the present study, we investigated GnT-V expression in human hepatocellular carcinoma (HCC) tissues. High expression of GnT-V mRNA was observed in both HCC and the surrounding tissues but not in normal liver. Immunohistochemical study using a newly established monoclonal antibody against GnT-V revealed that positive staining of GnT-V was observed in 75% of HCC tissues and 60% of surrounding tissues and that liver cirrhosis showed much stronger staining of GnT-V than chronic hepatitis without liver cirrhosis (p = 0.0035). In contrast, all of 12 cases of atypical adenomatous hyperplasia diffusely expressed GnT-V. beta1-6 branching in N-glycans, products of GnT-V, was increased in HCC tissues with high expression of GnT-V, as judged by lectin blotting. Levels of GnT-V expression in HCC tissues were positively correlated with a low Ki-67 labeling index (p = 0.0009), small size (p < 0.0001), poor differentiation (p < 0.0001) and absence of portal invasion (p = 0.018). Furthermore, HCC cases with low or no expression of GnT-V were more likely to show recurrence than cases with high expression (p = 0.0373). These findings strongly suggest that GnT-V expression is concerned mainly with an early phase of hepatocarcinogenesis.

Aged↗

PubMed2001

Construction of tumor-specific cells expressing a membrane-anchored single-chain Fv of anti-ErbB-2 antibody.

Cells expressing a membrane-anchored single-chain fragment variable (scFv) domain against a tumor-specific antibody were fabricated. These cells were able to bind to cells of a human colon cancer line (BM314) expressing the erbB-2 proto-oncogene. A plasmid, pMFverbB, was first constructed in which the anti-ErbB-2 scFv gene was cloned in-frame between a signal peptide sequence and the platelet-derived growth factor receptor (PDGFR) transmembrane domain gene to express scFv on the cell surface. An African green monkey cell line, COS-1, was stably transfected with pMFverbB. Immunofluorescence assay experiments and microscopic observation showed that the cells expressing scFv bound to the human tumor cells overexpressing the ErbB-2 protein as well as to cells of a mouse fibroblast line (NIH-3T3) transfected with the erbB-2 gene. The cells expressing scFv could take up magnetite cationic liposomes as a model of particle-type drug and retained the ability to target ErbB-2-expressing cells. The fabricated cells have the potential to serve as drug carriers in drug targeting applications.

3T3 Cells↗

PubMed2001

Correlation of three-dimensional gradient echo dynamic MR imaging with CT during hepatic arteriography in patients with hypervascular hepatocellular carcinomas: preliminary clinical experience.

The purpose of this study is to elucidate the usefulness of dynamic MR study of the whole liver using 3DFISP with double dose gadolinium (Gd) enhancement in detecting enhancing lesions in 20 patients. Twenty patients with hepatocellular carcinoma (HCC) underwent 3DFISP dynamic study with double dose Gd. The demonstration of enhancing hypervascular lesions regardless of etiology was evaluated on a segment-by-segment basis with receiver operating characteristic (ROC) analysis, using findings on CT during hepatic arteriography as a gold standard. Diagnostic accuracy of 3DFISP in the detection of HCC was also evaluated. As to the demonstration of enhancing lesions, the Az value of the ROC curve was 88%. The detection rate of HCC with 3DFISP was 98%. 57% of enhancing pseudolesions were not detected on 3DFISP. We concluded that Dynamic MR study of the whole liver using 3DFISP with double dose Gd enhancement is a useful method to demonstrate hypervascular HCC.

Aged↗

PubMed2001

Percutaneous ulnar artery approach for coronary angiography: a preliminary report in nine patients.

The radial artery approach is becoming more popular for diagnostic cardiac catheterization and interventional procedures because of its lower incidence of access site complications and decreased patient discomfort after the procedure. However, Allen's test reveals inadequate blood supply through the ulnar artery to the hand, and therefore the approach does not seem to be suitable in 10%-30% of patients. Here we demonstrated a new percutaneous ulnar artery approach for coronary angiography in nine patients. We succeeded in obtaining an entry site into the left ulnar artery in seven patients. The average time for cannulation and that for catheterization procedure were comparable with those of the radial approach previously reported from other laboratories. Complications such as bleeding, loss of an ulnar pulse, ulnar nerve injury, and the formation of an aneurysm or fistula were not observed in any patient. The ulnar approach may be another technique that decreases patient discomfort and risk, while preserving the radial artery as a potential coronary bypass graft for surgical myocardial revascularization. Cathet Cardiovasc Intervent 2001;53:410-414.

Adult↗

PubMed2001

Large-scale plant micropropagation.

Plant micropropagation is an efficient method of propagating disease-free, genetically uniform and massive amounts of plants in vitro. The micropropagation from cells can be achieved by direct organogenesis from hairy roots or regeneration via somatic tissue. Once the availability of embryogenic cell and hairy root systems based on liquid media has been demonstrated, the scale-up of the whole process should be established by an economically feasible technology for their large-scale production in appropriate bioreactors. It is necessary to design a suitable bioreactor configuration that can provide adequate mixing and mass transfer while minimizing the intensity of shear stress and hydrodynamic pressure. Automatic selection of embryogenic calli and regenerated plantlets using an image analysis procedure should be associated with the system. Using the above systems, it will be possible to establish an advanced plant micropropagation system in which the plantlets can be propagated without soil under optimal conditions controlled in plant factory. The aim of this review is to identify the problems related to large-scale plant micropropagation via somatic embryogenesis and hairy roots, and to summarize the most recent developments in bioreactor design. Emphasis is placed on micropropagation technology and computer-aided image analysis, including the successful results obtained in our laboratories.

Bioreactors↗

PubMed2001

Hepatic nodular hyperplasia in a boy with Alagille syndrome: CT and MR appearances.

A boy with Alagille syndrome complicated by hepatic nodular hyperplasia (HNH) is reported. During pre-transplantation evaluation, CT and MRI revealed a large hepatic lesion with multiple small nodular lesions. Angiography demonstrated a large hypervascular lesion and CT arterial portography (CTAP) showed a portal perfusion defect corresponding to the lesion. CTAP also revealed large portal vein branches running through the lesion. Although hepatocellular carcinoma is known to accompany Alagille syndrome, HNH should also be considered when large vessels running through the lesion are demonstrated.

Alagille Syndrome↗

PubMed2001

Augmentation of MHC class I antigen presentation via heat shock protein expression by hyperthermia.

Heat shock proteins are recognized as significant participants in immune reactions. In this study, we have demonstrated that the cell surface presentation of MHC class I antigen was increased in tandem with increased heat shock protein 70 (HSP70) expression and the immunogenicity of rat T-9 glioma cells was enhanced by hyperthermia. T-9 cells showed growth inhibition for 24 h after the heat treatment at 43 degrees C for 1 h in vitro, but then resumed a normal growth rate. HSP70 expression reached a maximum at 24 h after heating. Flow cytometric analysis revealed a significant increase in MHC class I antigen on the surface of the heated cells. The augmentation of MHC class I surface expression started 24 h after heating and reached a maximum 48 h after heating. The expression of other immunologic mediators, such as intracellular adhesion molecule-1 (ICAM-1) and MHC class II antigens, did not increase. In an in vivo experiment using immunocompetent syngeneic rats (F344), growth of the heated T-9 cells, with augmentation of MHC class I antigen surface expression, was significantly inhibited, while the cells grew progressively in nude rats (F344/N Jcl-rnu). Furthermore, compared with lymphocytes from non-immunized (PBS only injection) rats or rats injected with non-heated T-9 cells, the splenic lymphocytes of the rats in which the heated T-9 cells were injected displayed specific cytotoxicity against T-9 cells. These results suggest that HSP70 is an important modulator of tumor cell immunogenicity, and that hyperthermic treatment of tumor cells can induce the host antitumor immunity via the expression of HSP70. These results may benefit further efforts on developing novel cancer immunotherapies based on hyperthermia.

Animals↗

PubMed2001

MR imaging findings of uterine endometrial stromal sarcoma: differentiation from endometrial carcinoma.

Endometrial stromal sarcoma (ESS) is a rare malignant neoplasm of the uterus. We retrospectively analyzed pelvic MR imaging in 8 cases of ESS to determine the characteristic MR findings of ESS. Magnetic resonance images of 8 cases of ESS were evaluated for findings including the size, margin of the tumor, nodular lesions at the tumor margin, intramyometrial worm-like nodular extension, multiple nodular mass formation, hemorrhage, and necrosis in the tumor. The degree of contrast enhancement was also analyzed. The MR imaging findings of 21 consecutive cases of endometrial carcinoma (EC) were also evaluated and compared with those of ESS. The mean and the standard deviation of the maximum diameter of ESS and EC were 8.80 +/- 4.99 and 3.93 +/- 2.47 cm, respectively. Increased enhancement in at least a part of the tumor was observed in five of the six analyzed ESS cases and in 2 of 12 analyzed EC cases. The irregular margin, nodular lesions at the margin, intramyometrial nodular extension, and multiple nodular mass formation were more frequently seen in cases of ESS than in cases of EC. Magnetic resonance imaging can play a role in both diagnosing ESS as well as in differentiating ESS from EC.

Aged↗

PubMed2001

Quantitation of fetal DNA in maternal serum in normal and aneuploid prenancies.

We investigated whether the amount of circulating cell-free fetal DNA in maternal serum is influenced by fetal karyotype, using real-time quantitative polymerase chain reaction assay. Serum samples were obtained from pregnant women at gestational ages ranging from 15 to 17 weeks, prior to their undergoing amniocentesis. In total, we examined 70 samples consisting of 55 cases of pregnancy with 46,XY, 5 cases with 47,XY,+21, 3 cases with 47,XY,+18, a single case with 46,XY,dup(1) and 2 cases with twins of 46,XY, and 4 cases with 46,XX which were used as negative controls. We measured the concentration of the SRY sequence as a molecular marker for fetal DNA. The SRY sequence was detectable and measurable when the fetuses were male except for one case with 47,XY,+18. This case showed fetal growth retardation and bradycardia. No amplification signals of the SRY sequence were detected when the fetuses were female. The mean concentration of fetal DNA in maternal serum was 31.5 copies/ml in the pregnancy with 46,XY, 23.5 copies/ml in the pregnancies with 47,XY,+21 and 21.5 copies/ml in the pregnancies with 46,XY,+18. There were no significant differences in the concentration of fetal DNA between pregnancies with fetuses of normal karyotype and those with fetuses of abnormal karyotype.

Aneuploidy↗

PubMed2001

Effects of idoxifene and estradiol on NF-kappaB activation in cultured rat hepatocytes undergoing oxidative stress.

BACKGROUND/AIMS: Idoxifene is a tissue-specific selective estrogen receptor modulator. Estradiol is a potent endogenous antioxidant, and nuclear factor kappaB (NF-kappaB) is a key transcription factor that induces multiple genes in response to inflammation or oxidative stress. The aim of this study was to explore the inhibitory effects of idoxifene and estradiol on NF-kappaB activation in hepatocytes in a state of oxidative stress. METHODS: Lipid peroxidation was induced in cultured rat hepatocytes by incubation with ferric nitrilotriacetate solution. NF-kappaB activity was evaluated by electrophoretic mobility shift assay. RESULTS: The oxidative stress-induced activation of NF-kappaB and degradation of IkappaB-alpha were maximal at 3-5 h, with an increase in lactate dehydrogenase (LDH) and malondialdehyde (MDA) secretion into the culture medium. Treatment with idoxifene and estradiol inhibited IkappaB-alpha degradation and NF-kappaB activation through the attenuation of hepatocyte oxidative bursts and decreased extracellular levels of LDH and MDA. In addition, idoxifene and estradiol inhibited lipid peroxidation in rat liver mitochondria. A potent NF-kappaB inhibitor, pyrrolidine dithiocarbamate, prevented NF-kappaB activation by inhibition of IkappaB-alpha degradation and decreased LDH and MDA levels, suggesting that NF-kappaB might be a regulator in a genetic response to increase oxidative stress-induced hepatic injury. CONCLUSIONS: These findings suggest that idoxifene and estradiol function as antioxidants and protect hepatocytes from inflammatory cell injury.

Animals↗

PubMed2001

Heat-inducible TNF-alpha gene therapy combined with hyperthermia using magnetic nanoparticles as a novel tumor-targeted therapy.

Heat-induced therapeutic gene expression is highly desired for gene therapy to minimize side effects. Furthermore, if the gene expression is triggered by heat stress, combined therapeutic effects of hyperthermia and gene therapy may be possible. We combined TNF-alpha gene therapy driven by the stress-inducible promoter, gadd 153, with hyperthermia using magnetite cationic liposomes (MCLs). In nude mice, MCLs induced cell death throughout much of the tumor area on heating under an alternating magnetic field. This heat stress also resulted in a 3-fold increase in TNF-alpha gene expression driven by the gadd 153 promoter as compared with that of nonheated tumor. TNF-alpha gene expression was also observed in the peripheral area where the hyperthermic effect was not enough to cause cell death. The combined treatment strongly arrested tumor growth in nude mice over a 30-day period, suggesting potential for cancer treatment.

Animals↗