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Biomedical subjects

H Shibuya

Publications and source records attributed to H Shibuya.

At least 217 records · Page 12Linked to original sources

[Laser photodynamic therapy for central-type lung cancer].

Laser endoscopic surgery is recognized as an effective treatment for lung cancer. Attention has increasingly been focused on photodynamic therapy (PDT) with dihermatoporphyrin ethers. The Japanese government approved the use of this therapy in October 1995, and reimbursement through the national health insurance system began in April 1996. Over the past decade, 140 patients (283 lesions) with central type lung cancers have been treated at our hospital. Overall complete remission was obtained in 39.6% of 112 lesions, partial remission in 59.4% and no remission in 1.0% The indications for PDT are as follows: 1. Early stage lung cancer curative; among 95 early stage lesions complete remission was obtained in 79 (83.2%), and 71 patients were disease free at 3 to 176 months. 2. Advanced lesions opening of bronchi; overall, "effective" opening of bronchi was achieved in 61 of 81 lesions (75%), in the PDT group, and in 143 of 177 (81%) in the Nd-YAG laser therapy groups. 3. Preoperative laser irradiation to increase operability and reduce the extent of operation; the extent of resectin was reduced, or inoperable lesions were made operable in 21 of 24 patients treated. 4. Multiple primary lung cancer. The success of clinical trials of PDT for treatment of lung cancers bodes well for its future use. More stable, definitive, and successful treatment will become possible with the use of new dyes that distribute more evenly in tumor tissue, and with the deeper tissue penetration made possible by longer-wavelength beams.

Adenocarcinoma↗

Identification of a member of the MAPKKK family as a potential mediator of TGF-beta signal transduction.

The mitogen-activated protein kinase (MAPK) pathway is a conserved eukaryotic signaling module that converts receptor signals into various outputs. MAPK is activated through phosphorylation by MAPK kinase (MAPKK), which is first activated by MAPKK kinase (MAPKKK). A genetic selection based on a MAPK pathway in yeast was used to identify a mouse protein kinase (TAK1) distinct from other members of the MAPKKK family. TAK1 was shown to participate in regulation of transcription by transforming growth factor-beta (TGF-beta). Furthermore, kinase activity of TAK1 was stimulated in response to TGF-beta and bone morphogenetic protein. These results suggest that TAK1 functions as a mediator in the signaling pathway of TGF-beta superfamily members.

Amino Acid Sequence↗

The coding sequence of the bovine ferrochelatase gene.

The amino acid code and surrounding regions in the bovine ferrochelatase gene were amplified by a combination of reverse transcriptase PCR and vectorette PCR and sequenced. The bovine code was 86% homologous to the human ferrochelatase code but was altered at a position corresponding to the presumed human initiator codon.

Amino Acid Sequence↗

The relation between an esophageal cancer and associated cancers in adjacent organs.

BACKGROUND: The relation between esophageal cancers and head and neck tumors was studied in order to improve the treatment results in patients with multiple cancers. METHODS: We reviewed the records of 3,375 patients with an indexed squamous cell carcinoma of the head and neck treated at our institution between 1960 and 1994; and 81 patients were found to have an associated esophageal carcinoma. Similarly, the records of 434 patients with an indexed esophageal cancer were reviewed; and 54 patients had cancers in other organs or in the residual esophagus. A total of 135 esophageal cancers with 154 synchronous or metachronous cancers were entered into the analysis. RESULTS: The risk of developing esophageal cancer was ten times higher in male patients with head and neck cancer than in female patients. Synchronous or metachronous esophageal cancer associated with head and neck cancer was most frequently seen with pharyngeal cancer (28/360 = 7.8%), followed by in the oral cavity (47/2148 = 2.2%). CONCLUSIONS: Better knowledge of the relation between an esophageal cancer and a head and neck cancer may lead to the early detection of subsequent small, potentially curable neoplasms sited in either the esophagus or the head and neck region.

Carcinoma, Squamous Cell↗

Sens-A-Ray characteristics with variations in beam quality.

This study examined the relationship between x-ray beam quality and image characteristics with the use of the Sens-A-Ray (Regam Medical Systems, Sundsvall, Sweden). To evaluate the x-ray response, properties of the image sensor, dark current and statistical noise, sensitivity, and contrast resolution were measured. Tube voltage, tube current, and exposure time were varied. Exposures were determined with the use of an ionization chamber. Pixel values beneath a lead strip were used to calculate dark current effects. Contrast was measured with pixel values from the images of a step-wedge. Dark current noise increased in proportion to exposure time. Although the sensitivity at each tube voltage was linear and proportional to the exposure, the gradient was inversely proportional to increased tube voltage. After subtraction of the dark current and statistical noise, the gradient of the sensitivity at low tube voltage remained steeper than at high tube voltages. Hence, sensitivity decreased with increased tube voltage. Sensitivity gradients at each different tube current were similar. Irrespective of exposure, contrast resolution between adjoining step-wedge steps > or = 9 mm were too small to distinguish at 50 kVp. The gray levels for each step below 12 mm in thickness were distinguishable with 90 kVp. Increased dark current noise consequent to long exposure times narrowed the available gray scale range. Lower tube voltage resulted in higher sensitivity with larger gradients than higher tube voltages.

Analog-Digital Conversion↗

A case of subacute necrotizing fasciitis.

We report a 48-year-old woman who developed necrotizing groin fasciitis with insidious onset. Before she visited us, she had been unsuccessfully treated with several kinds of antibiotics by other doctors for one month, because of a small ulcer covered by blackish necrotic tissue. She was referred to us because of high fever, an ulcer on the left labium majus, and a cellulitis-like lesion with severe pain on the lower abdomen. Methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus intermedius, and Bacteroides uniformis were isolated from the wound. After aggressive debridement on the eighth day after admission of the whole indurated area and the fascia of the underlying muscle, healthy granulation tissue covered the defect, and the wound was finally closed with a skin graft Long-term administration of antibiotics along with insufficient and delayed surgical treatment were considered to have caused the full development of this disease.

Acute Disease↗

Hepatic pseudolesion in the left lobe around the falciform ligament at helical CT.

PURPOSE: To determine the prevalence and possible cause of pseudolesions in the left hepatic lobe around the falciform ligament at hepatic helical computed tomography (CT). MATERIALS AND METHODS: Portal venous-dominant CT scans of 472 consecutive patients were reviewed. CT of the left hepatic lobe was performed after injection of contrast material into the portal vein in 73 patients, the hepatic artery in 32, and the internal thoracic artery in four. The scans were compared with those obtained at helical CT, and the findings were analyzed. RESULTS: Pseudolesions were seen on 64 (14%) of 472 helical CT scans and correlated well (accuracy, 96%) with portal perfusion defects. They were not more enhanced than the surrounding liver parenchyma at CT arteriography with hepatic artery injection but were enhanced in two patients at CT arteriography with internal thoracic artery injection. CONCLUSION: Pseudolesions are caused by portal perfusion defects and may receive an aberrant blood supply.

Adolescent↗

Hepatic hemangioma: findings with two-phase CT.

PURPOSE: To characterize the appearance of hemagiomas at two-phase dynamic incremental computed tomography (CT) and to determine the cause of contrast material enhancement of adjacent parenchyma in the first series. MATERIALS AND METHODS: Contrast-enhanced CT images of 51 hemangiomas in 20 patients were reviewed. Enhancement patterns of hemangiomas in the first series were classified as homogeneous high, peripheral high, and low attenuation; in the second series, as homogeneous high, peripheral high, iso-, and low attenuation. Correlations between arterioportal shunts and early parenchymal enhancement were evaluated in 45 hemangiomas in the 17 patients who underwent angiography. RESULTS: Thirty-two hemangiomas progressively became enhanced. Four had low and eight had homogeneous high attenuation in both series. Seven changed from homogeneous high to isoattenuation. Early parenchymal enhancement was well correlated with presence of arterioportal shunt. CONCLUSION: Low-attenuation hemangiomas and those that changed from homogeneous high to isoattenuation are atypical and difficult to differentiate from other neoplasms. Most early parenchymal enhancement is caused by associated arterioportal shunts.

Angiography↗

Taxol and its related taxoids from the needles of Taxus sumatrana.

Through bioassay-guided separation of the chemical constituents of the needles of Taxus sumatrana, taxol (1), cephalomannine (2), and a new taxoid 19-hydroxy-13-oxobaccatin III (8) have been isolated together with 7-epi-10-deacetyltaxol (3), 7-epi-10-deacetylcephalomannine (4), baccatin III (5), 19-hydroxybaccatin III (6), and 10-deacetyl-13-oxobaccatin III (7). The chemical structure of 8 has been elucidated on the bases of its chemical and physicochemical properties.

Antineoplastic Agents↗

External and interstitial radiotherapy in the treatment of oropharyngeal squamous cell carcinoma.

The records of 165 patients with squamous cell carcinoma of the oropharynx treated at our hospital with external and/or interstitial radiotherapy between 1971 and 1990 were reviewed to evaluate the treatment results, focusing on primary control and complications. All cancers were restaged according to the UICC 1987 TNM staging system. Of these 165 patients, 11% were in Stage I, 55% in Stage II, 24% in Stage III and 8.5% in Stage IV. Local control and complications were analysed in 140 patients. The remaining 25 patients died of intercurrent or metastatic disease during the first 2 years following treatment and were excluded from the analysis. 70 patients were treated by interstitial implant using permanent implant seeds (Rn-222 in eight patients, Au-198 in 62 patients) with or without external radiation. 56 other patients received external irradiation alone and another 14 patients received pre-operative external irradiation plus surgery. 2-year recurrence-free rates were 73% (100% for T1, 76% for T2, 36% for T3 tumours) in the patients who received interstitial implant with or without external radiation and 36% (67% for T1, 48% for T2, 13% for T3 tumours) in the patients treated by external irradiation alone. The incidence of soft-tissue or bone complications requiring long-term treatment was 14%. Based on these findings, it is believed that an interstitial implant using Au-198 grains combined with external beam irradiation is a useful treatment modality for small lesions of the oropharynx.

Adult↗

Nucleotide sequence of alpha-galactosidase cDNA from Mortierella vinacea.

To analyze the primary structure of Mortierella vinacea alpha-galactosidase, a cDNA library of M. vinacea mRNA in lambda gt10 was constructed. A clone, which has an insert size of about 1.4 kilobase pairs, was found to contain the coding region of the mature enzyme. The deduced amino acid sequence share that the mature enzyme consisted of 397 amino acid residues with a molecular mass of 44,350 Da. The sequence identity of the mature enzyme with alpha-galactosidases from Saccharomyces carlsbergensis, Cyamopsis tetragonoloba (guar), and human were 47%, 43%, and 34%, respectively.

Amino Acid Sequence↗

Purification and some properties of alpha-galactosidase from Penicillium purpurogenum.

alpha-Galactosidase was purified by ion-exchange chromatographies on DEAE-cellulose and SE-cellulose columns from the culture filtrate of Penicillium purpurogenum No. 618. The final preparation was judged homogeneous by SDS-PAGE and its molecular mass and isoelectric point were estimated to be 67 kDa and 4.1, respectively. The N-terminal amino acid sequence of the enzyme was analyzed and aligned with those of other alpha-galactosidases. In addition, the enzyme acted on the stubbed alpha-galactosyl residue connected to the beta-1,4-manno-oligosaccharide chain, indicating that this specificity was quite different from that of Mortierella vinacea alpha-galactosidase.

Amino Acid Sequence↗