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Biomedical subjects

H Hoshi

Publications and source records attributed to H Hoshi.

At least 397 records · Page 22Linked to original sources

Multidisciplinary treatment of head and neck cancer using BCG, OK-432, and GE-132 as biologic response modifiers.

Since 1979, we have performed multidisciplinary treatment using intensive immunotherapy with biologic response modifiers (BRM) in combination with surgical treatment of oral cancer. Chemotherapy and radiotherapy were also included as part of the therapy. A historic control study was performed. Adjuvant therapy was administered by standardized methods, and the distribution of patients at various stages was similar between groups. The immunotherapy group showed a shorter treatment period, lower rates of recurrence, metastases, and side effects, greater histologic effects at the end of the first treatment, and a higher survival rate than the nonimmunotherapy group. Immunologically, immunotherapy tended to promote positive immune reactions and inhibit negative immune reactions.

Antineoplastic Agents↗

Fibroblast growth factor stimulates the gene expression and production of tissue inhibitor of metalloproteinase-1 in bovine granulosa cells.

The hormonal control of tissue inhibitor of metalloproteinase-1 (TIMP-1) gene expression and production by growth factors, gonadotrophins, and serum factors in cultured bovine granulosa cells (BGC) were investigated. Confluent cultures of BGC were exposed to various factors in a defined medium and levels of TIMP-1 in the conditioned medium were determined by enzyme immunoassay. Basic fibroblast growth factor (bFGF) and acidic fibroblast growth factor (aFGF) showed potent stimulation of cell proliferation and TIMP-1 production by BGC, while insulin stimulated growth but not TIMP-1 production. Basic FGF stimulated TIMP-1 production and BGC cell proliferation in a dose-dependent manner. A time course of TIMP-1 production showed substantially increased levels between 18 and 24 h in both control and bFGF-stimulated BGC cultures with bFGF-stimulated cultures having markedly higher TIMP-1 production at all time points. Consistent with the TIMP-1 production data, bFGF and aFGF increased the expression of TIMP-1 mRNA as determined by northern blot analysis, while insulin, inhibited TIMP-1 mRNA levels. These results indicate that FGF-induced TIMP-1 production by BGC may support bovine embryo development in vitro.

Animals↗

Differential alterations in levels of hepatic microsomal cytochrome P450 isozymes following intracerebroventricular injection of bacterial lipopolysaccharide in rats.

To investigate the effect of central inflammation due to bacterial infection, such as meningitis, on the activities of hepatic cytochromes P450 (CYPs), rats were injected intracerebroventricularly (i.c.v.) with 0.1 microg of bacterial lipopolysaccharide (LPS). The LPS i.c.v. injection significantly decreased the total P450 contents (by 30% of the levels of control rats treated with saline i.c.v.), the contents of CYP1A (48%), 2B (54%), 2C11 (37%) and 3A (40%) and related drug metabolizing activities, 7-ethoxycoumarin O-deethylation (36%), imipramine N-demethylation (41%) and erythromycin N-demethylation (33%) in liver microsomes 24 h after the treatment. In contrast, intraperitoneal (i.p.) injection of LPS at the same dose as i.c.v. (0.1 microg) did not significantly affect the hepatic microsomal contents of total P450 or the content of each individual CYP isozyme and its activity. CYP2D1 protein and the activity of imipramine 2-hydroxylase were not significantly decreased by LPS injection regardless of the route of administration. The inhibitory effects of 0.1 microg i.c.v. LPS on the activities of these CYPs were almost equal to those of 10 microg i.p. LPS, and 0.01 microg of i.c.v. LPS significantly decreased the activity of imipramine N-demethylase only. Therefore, the LPS i.c.v. injection resulted in CYP isozyme-selective inhibition at an ineffective dose when injected i.p.. It is suggested that a central inflammation, such as meningitis, differentially decreases the levels of hepatic CYP isozymes. A possible involvement is discussed of the central nervous system in this down-regulation.

Animals↗

Confluent hepatic fibrosis in cirrhosis: ferumoxides-enhanced MR imaging findings.

We describe ferumoxides-enhanced magnetic resonance imaging findings in a 60-year-old man with confluent hepatic fibrosis in advanced cirrhosis. The extension and internal structure of confluent fibrosis were well demonstrated with ferumoxides-enhanced proton-density spin-echo magnetic resonance images, showing a wedge-shaped area of high signal intensity corresponding to the extension of fibrosis and internal focal areas of low signal intensity, presumably corresponding to residual functioning liver parenchyma. This case suggests a potential utility of ferumoxides-enhanced magnetic resonance imaging for characterizing this tumor-mimicking disorder.

Contrast Media↗

Nonpathological focal enhancements on spiral CT hepatic angiography.

BACKGROUND: To assess the frequency and characteristics of nonpathological focal enhancements seen on spiral computed tomographic (CT) hepatic angiography (CTA). METHODS: Spiral CTA and spiral CT arterial portography (CTAP) were performed in 31 patients with suspected liver malignancy prior to potential liver resection. The CTA images were retrospectively reviewed for focal enhancements by two radiologists. After determining nonpathological focal enhancements on CTA images based on the other radiographic tests, surgical exploration including intraoperative sonography, follow-up imagings, the frequency, size, site, and shape of nonpathological focal enhancements with CTA were assessed. RESULTS: Thirty-six nonpathological focal enhancements with CTA from 4 to 23 (mean = 11. 4) mm were seen in 14 (45.2%) of 31 patients. Thirteen (36.1%) of 36 nonpathological focal enhancements with CTA were not depicted with CTAP. Nonpathological focal enhancements with CTA were frequent in Couinaud segments III (27.8%), V (22.2%), and VI (19.4%). Twenty-three (63.9%) of 36 nonpathological focal enhancements were located in the edge of the liver. Shapes of 36 nonpathological focal enhancements with CTA included circular (n = 16), worm (n = 7), irregular (n = 6), dot (n = 6), and wedge (n = 1). CONCLUSION: In nearly half of patients, spiral CTA shows various shapes of small nonpathological focal enhancements more frequently in the liver edge.

Aged↗

Methodological assessment of combined spiral CT angiography and CT arterial portography.

BACKGROUND: To assess an optimal methodology of combined spiral computed tomographic (CT) angiography (CTA) and CT arterial portography (CTAP) for detection and characterization of liver tumors. METHODS: We performed spiral CTAP only in five patients with 30-32% contrast (subset A), CTAP combined with preceding spiral CTA using 30-32% contrast in 19 (subset B), and CTAP combined with preceding spiral CTA with 60-64% contrast in seven (subset C). The CT numbers of the aorta immediately before preceding CTA and subsequent CTAP and the CT numbers of malignant tumor and liver parenchyma with CTAP were measured. RESULTS: The differences of the CT number between the malignant tumor and liver parenchyma on CTAP were 61.1-161.8 (mean +/- SD, 114.5 +/- 39.3) HU, 50.7-164.8 (104.2 +/- 31.2) HU, and 101.2-368.3 (219.5 +/- 90.5) HU in subsets A, B, and C, respectively. Two cavernous hemangiomas showed pathognomonic findings with preceding CTA. CONCLUSION: Combination of preceding spiral CTA and subsequent spiral CTAP using 30% contrast with a 5-min interval is an optimal method for detection and characterization of liver tumors.

Aged↗

Detection of hepatic tumors: arterial-phase MR imaging versus spiral CT arteriography.

BACKGROUND: To compare the utility of arterial-phase magnetic resonance (APMR) imaging and spiral computed tomography arteriography (CTA) for detection of hepatic tumors. METHODS: Both APMR imaging and CTA were performed in 24 patients with liver tumors. APMR imaging was initiated at 25-30 s after an intravenous bolus injection of gadolinium-diethylenetriamine pentaacetic acid using the fast multiplanar spoiled GRASS technique. CTA was initiated at 3 s after hepatic arterial injection of 30-64% nonionic contrast agent. APMR and CTA images were separately reviewed retrospectively by two blinded readers. Afterward, matched pair was reviewed to determine which had better lesion conspicuity. RESULTS: The sensitivities for hepatic tumors were 67.2 and 86.6% in APMR and CTA, respectively (p < 0.01). Seven (12.5%) and 21 (23.9%) false-positive lesions were seen at APMR and CTA, respectively (NS). Lesion conspicuity was comparable between APMR and CTA. CONCLUSIONS: Although APMR imaging is an useful noninvasive method to detect hypervascular liver tumors, APMR imaging is still not an alternative to CTA with respect to tumor detectability.

Aged↗

Small hepatic nodules in cirrhosis: ultrasonographic, CT, and MR imaging findings.

PURPOSE: The purpose of this study was to assess the imaging findings of pathologically-proved small hepatic nodules 2 cm in size or smaller detected with ultrasonography in cirrhotic patients with suspected hepatocellular carcinoma (HCC). MATERIALS AND METHODS: We evaluated sonographically detected 32 small hepatic nodules which were pathologically confirmed in 23 consecutive cirrhotic patients who were suspected of having HCC. Twenty-six lesions were confirmed with ultrasonographically-guided aspiration needle-core biopsy, and six with definitive surgery. Ultrasonographic examination records were retrospectively reviewed. CT, and MR images obtained with various imaging techniques were retrospectively reviewed by two radiologists in a blind fashion. RESULTS: The 32 hepatic nodules were comprised of seven focal fatty changes, two large regenerative nodules, three low-grade dysplastic nodules, five high-grade dysplastic nodules, and fifteen HCCs. Ultrasonography showed various echogenicity for the hepatic nodules. The signal-intensity characteristics with T1-weighted spin-echo, in-phase gradient-recalled-echo, and dynamic MR imagings may be useful in distinguishing HCC from nonHCC nodules. CONCLUSIONS: Nearly half of small hepatic nodules detected with ultrasonography were nonHCC nodules. Ultrasonographic findings may not be reliable in characterizing small hepatic nodules in cirrhosis. CT and MR imaging obtained with the various techniques are still insensitive to these hepatic nodules.

Aged↗

Detection of lymph-node metastases in patients with gastric carcinoma: comparison of three MR imaging pulse sequences.

BACKGROUND: To compare the diagnostic accuracy of magnetic resonance (MR) images obtained with three different pulse sequences for lymph-node metastases in patients with gastric cancer. METHODS: T1-weighted spin-echo (SE), breath-hold T2-weighted fast SE, and triphasic gadolinium-enhanced dynamic gradient-recall-echo (GRE) MR images obtained in 16 patients with gastric carcinoma were retrospectively reviewed. Regional lymph nodes were assigned to four different groups, and image review was conducted on a lymph-node group-by-group basis; 64 lymph-node groups were reviewed by two radiologists. Relative sensitivity, specificity, and accuracy were determined based on the findings with definitive surgery and follow-up imaging. Diagnostic accuracy was determined by means of receiver-operating-characteristic (ROC) analysis. RESULTS: Relative sensitivities for lymph-node metastases with T1-weighted SE, breath-hold T2-weighted fast SE, and dynamic GRE images were 61%, 94%, and 59%, respectively. Relative sensitivity with breath-hold T2-weighted fast SE images was significantly greater than that with T1-weighted SE (p < 0.05) and dynamic GRE (p < 0.05) images. Diagnostic accuracy determined by ROC analysis was marginally higher with breath-hold T2-weighted fast SE (area under ROC curve [Az] = 0.87) than with T1-weighted SE (Az = 0.78, p = 0.08) and dynamic GRE (Az = 0.79, p = 0.12) images. CONCLUSION: Breath-hold T2-weighted fast SE sequence is useful in the detection of regional lymph-node metastases in patients with gastric carcinoma.

Abdomen↗

Comparison of diclofenac and fluorometholone in preventing cystoid macular edema after small incision cataract surgery: a multicentered prospective trial.

PURPOSE: To compare a nonsteroidal topical solution (0.1% diclofenac) to a steroidal topical solution (0.1% fluorometholone) in preventing cystoid macular edema (CME) and disruption of the blood-aqueous barrier. METHODS: A multicentered, prospective clinical trial was performed on eyes undergoing phacoemulsification followed by implantation of a foldable acrylic intraocular lens by the envelope technique. The presence and degree of cystoid macula edema (CME) was determined by fluorescein angiography. A breakdown of the blood-aqueous barrier was determined by laser flare-cell photometry. RESULTS: Five weeks after surgery, CME was present in 3 of 53 eyes (5.7%) receiving diclofenac and in 29 of 53 eyes (54.7%) receiving fluorometholone. This difference was statistically significant (P < .001). The amount of flare in the anterior chamber at 3 days, 1, 2, 5, and 8 weeks after surgery was also significantly lower (P < .01-P < .001) in the diclofenac group. The degree of flare at 3 days, 1, 2, 5, and 8 weeks after surgery was significantly higher in eyes with CME (P < .001). CONCLUSIONS: These findings suggest that diclofenac effectively prevents CME following cataract surgery and that CME is closely related to the breakdown of the blood-aqueous barrier.

Aged↗