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Biomedical subjects

F Watanabe

Publications and source records attributed to F Watanabe.

At least 55 records · Page 3Linked to original sources
PubMed2000

[Arteriovenous fistula associated with Staphylococcus aureus sepsis in a patient with Rendu-Osler-Weber syndrome].

A 58-year-old man with a history of cerebral infarction and bleeding due to duodenal ulcer was admitted with fever and arthralgia. Methicillin-sensitive Staphylococcus aureus (MSSA) was isolated from his peripheral blood. Bacteremia with MSSA was diagnosed, and antibiotic therapy was started. However, chest X-ray films and computed tomographic scans disclosed mass shadows in both lungs accompanied by dilated vascular markings. Pulmonary arteriography and magnetic resonance angiography revealed the existence of arteriovenous fistulas in both lungs. Ga scintigraphy disclosed a hot spot in the left lower lobe, consistent with the location of one fistula. This indicated that the fistula might be the focus of MSSA sepsis. Because the patient also had telangiectasia in his gastric mucosa, oral cavity, and nasal cavity, he was given a diagnosis of Rendu-Osler-Weber syndrome.

Arteriovenous Fistula↗
PubMed2000

[Chemotherapy with mitoxantrone for the treatment of recurrent breast cancer].

Two cases of recurrent breast cancer are reported in which chemotherapy with mitoxantrone proved remarkably effective. Case 1 was a 61-year-old postmenopausal female. At 32 postoperative months, multiple metastases of lung and bone were found. Following unsuccessful treatment with anthracyclin and an antiestrogenic agent, we used MVP modified therapy (mitoxantrone (MIT) 16 mg and vincristine (VCR) 1.6 mg once per 4 weeks and medroxyprogesterone acetate (MPA) 1,200 mg/day) and 5'-deoxy-5-fluorouridine (5'-DFUR) 800 mg/daily. After 12 cycles were performed, the patient showed a partial response (PR) (nearly complete response (CR)) on a chest X-ray and bone scintigram. Case 2 was a 49-year-old premenopausal female. At 42 postoperative months, a local recurrence was found and resection was performed. However, after endocrine therapy with goserelin acetate (ZOL) and chemotherapy with CAF (cyclophosphamide, adriamycin and 5-FU) and UFT, local recurrence and pleural effusion were found 6 months after surgical operation. We then used MVP modified chemotherapy and endocrine therapy with ZOL. The patient showed a PR at 9 cycles after therapy. MVP modified chemotherapy is considered an effective treatment for recurrent breast cancer, especially for adriamycin or epirubicin resistant breast cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

[The evaluation of pamidronate therapy for bone metastases from breast cancer].

We devised a method to evaluate comprehensively the therapy to alleviate the pain of bone metastases from breast cancer according to the three items of bone pain and effects of analgesia and radiology. In 12 patients, we evaluated the therapeutic effect of pamidronate as an alleviative treatment for the pain of bone metastases from breast cancer. Bone pain was evaluated on a 6-grade scale, as was use of analgesics. Improvement in bone pain, in addition to improvement in use of analgesia, was evaluated as markedly improved, improved, unchanged, aggravated, no pain or undeterminable. Radiological improvement in bone lesions was evaluated as markedly improved, improved, unchanged, aggravated or undeterminable. An overall evaluation was made by combining the above two. In this evaluation method, pamidronate therapy resulted in an evaluation of markedly improved in 2 patients, improved in 5, unchanged in 4 and aggravated in 1, demonstrating that the therapy was very useful as an alleviative treatment for the pain of bone metastases from breast cancer. The evaluation method, in which pain, a subjective complaint, is combined with use of analgesics, an objective factor, and to which radiological evaluation is added for further objectively, may in the future to be applicable for evaluation of various alleviative treatments of pain of bone metastases.

Adult↗
PubMed1999

Tissue-specific alternative splicing of rat brain fructose 6-phosphate 2-kinase/fructose 2,6-bisphosphatase.

We have reported the occurrence of eight splice variants of rat brain fructose 6-phosphate 2-kinase/fructose 2,6-bisphosphatase (RB2K). In the present study, we quantified these splice variants in various tissues using a RNAse protection assay and found a tissue-specific pattern of alternative splicing of the RB2K gene. Splice variants containing exon F were specifically expressed in brain. Moreover, exons D and E were spliced in brain, skeletal muscle and heart. Consequently, eight, six, four and two splice variants were expressed in brain, skeletal muscle, heart and liver plus testis, respectively. These results suggest that distinct RB2K isoforms could be involved in regulation of glycolysis in a tissue-specific manner.

Alternative Splicing↗
PubMed1999

Homology modeling of gelatinase catalytic domains and docking simulations of novel sulfonamide inhibitors.

Three-dimensional models for the catalytic domain of gelatinases (MMP-9 and -2) have been constructed based on the X-ray crystal structure of MMP-3. Conformations of the loop segment which forms the bottom half of the S1' subsite but shows conformational diversity among the crystal structures of other MMPs have been explored by simulated annealing of each gelatinase model complexed with two highly potent "probe" inhibitors. Representative catalytic domain models have been selected for each gelatinase from the set of generated conformations based on shape complementarity of the loop to the probe inhibitors. The single model selected for MMP-9 was utilized to explain the structure-activity relationship of our novel sulfonamide inhibitors. Molecular dynamics (MD) simulations of the complex models revealed important features of the binding mechanism of our inhibitors: (i) the ligand carboxylate group coordinating to the catalytic zinc ion and hydrogen bonding to the Glu219 side chain, (ii) one of the sulfonyl oxygens forming hydrogen bonds with the main chain NHs (Leu181 and Ala182), (iii) the sulfonyl substituent making extensive hydrophobic contact with the S1' subsite. The gauche conformation exclusively adopted by the sulfonamide C-N-S-C torsion plays an important role in achieving the third binding feature by properly directing the substituent into the S1' subsite. Improvement of the inhibitory activity according to straight elongation of the sulfonyl substituent was attributed to an increase of the hydrophobic contact between the substituent and the S1' subsite. Structural modifications which alter the straight shape of the substituent lead to deterioration of the activity. On the other hand, the two candidate models selected for MMP-2 differ in the bottom shape of the S1' subsite: one with a channel-like subsite and the other with a pocket-like subsite resembling that of the MMP-9 model. The bottom shape was experimentally probed by chemical synthesis of inhibitors having elongated sulfonyl substituents whose terminal alkyl groups were shown by MD simulations to protrude from the S1' subsite bottom into the solvent. Gelatinase assays of these inhibitors showed that elongation of the substituent significantly reduces activity against MMP-9 while retaining activity against MMP-2, consequently increasing the selectivity between MMP-2 and -9. The results confirm that MMP-9 has a pocket-like S1' subsite with a floorboard and MMP-2 has a channel-like S1' subsite.

Amino Acid Sequence↗
PubMed1999

A Case of Breast Cancer Metastatic to the Head of the Pancrea.

A case of breast cancer that metastasized to the head of the pancreas 6 yearsand 8 months after mastectomy is reported. The pancreas head metastasis was associated with general fatigue and obstructive jaundice. The serum levels of CEA, CA15-3 and NCC-ST-439, tumor markers of breast cancer, were within normal limits, but CA15-3 was immunohistochemically demonstrated in the resected metastatic lesion, in a manner similar to lobular carcinoma of the breast.

Journal Article↗
PubMed1999

Correlation of antiangiogenic and antitumor efficacy of N-biphenyl sulfonyl-phenylalanine hydroxiamic acid (BPHA), an orally-active, selective matrix metalloproteinase inhibitor.

The antiangiogenic activity and antitumor efficacy of a newly developed matrix metalloproteinase (MMP) inhibitor were examined. N-biphenyl sulfonyl-phenylalanine hydroxiamic acid (BPHA) potently inhibits MMP-2, -9, and -14, but not MMP-1, -3, or -7. In contrast, (-)BPHA, an enantiomer of BPHA, was inactive against all MMPs tested. Daily oral administration of 200 mg/kg BPHA, but not (-)BPHA in mice resulted in potent inhibition of tumor-induced angiogenesis, primary tumor growth, and liver metastasis. The growth inhibition activity of BPHA was 48% and 45% in a B16-BL6 melanoma and F2 hemangio-endothelioma model, respectively. BPHA also showed 42% inhibition of the liver metastasis of C-1H human colon carcinoma cells. These results indicate that selective MMP inhibition is correlated with antiangiogenic and antitumor efficacy and that the selective MMP inhibitor BPHA has therapeutic potential.

Animals↗
PubMed1999

Urocortin in human placenta and maternal plasma.

Plasma immunoreactive (IR-) urocortin (Ucn) and corticotropin-releasing factor (CRF) levels in pregnant women were measured by their specific radioimmunoassays after extraction. Although plasma IR-CRF levels were increased in pregnant women as compared to men and non-pregnant women, there was no difference of plasma IR-Ucn levels among groups. Ucn mRNA was detected in cytotrophoblasts and syncytiotrophoblasts by in situ hybridization. A reverse-phase high-performance liquid chromatography (HPLC) showed the major peak of IR-Ucn in placenta and plasma that had similar chromatographic mobility to synthetic Ucn1-40. These data suggest that Ucn is produced and processed into the same form of synthetic Ucn in placenta, but not secreted into maternal blood.

Adult↗
PubMed1999

Peptide synthesis catalyzed by organic solvent-stable protease from Pseudomonas aeruginosa PST-01 in monophasic aqueous-organic solvent systems.

The equilibrium yields of the peptide Cbz-Arg-Leu-NH2 synthesized from Cbz-Arg and Leu-NH2 using the PST-01 protease in the presence of organic solvents were investigated under various conditions. The equilibrium yields depended little on the concentration of the carboxyl component, but significantly on the concentration of the nucleophile. The optimum temperature and pH for a high equilibrium yield were 30 degrees C and greater than 5.0, respectively. Under optimum conditions the equilibrium yields were 71.6% and 87.7% in the presence of 50% (v/v) DMF and 60% (v/v) DMSO, respectively. Furthermore, the PST-01 protease also catalyzed the syntheses of the dipeptides Cbz-Lys-Leu-NH2, Cbz-Ala-Leu-NH2, Cbz-Ala-Phe-NH2, Cbz-Arg-Leu-NH2, and Cbz-Lys-Phe-NH2 with equilibrium yields of more than 60% in the presence of 50% (v/v) DMF and 50 mM sodium phosphate buffer (pH 7.0).

Journal Article↗
PubMed1999

Purification and characterization of organic solvent-stable protease from organic solvent-tolerant Pseudomonas aeruginosa PST-01.

An organic solvent-stable protease (PST-01 protease) in a culture broth of organic solvent-tolerant Pseudomonas aeruginosa PST-01 was purified by successive hydrophobic interaction chromatography using Butyl-Toyopearl gels. The purified enzyme was homogeneous as determined by SDS-polyacrylamide gel electrophoresis. PST-01 protease had a molecular mass of 38 kDa. The optimum temperature and pH for casein hydrolysis were 55 degrees C and 8.5, respectively. PST-01 protease was stable at pH 8-12 and below 50 degrees C and was determined to be a metalloprotease which was inhibited by EDTA, 1,10-phenanthroline, and phosphoramidon. PST-01 protease inhibited by EDTA was reactivated completely by the addition of zinc or cobalt ions. The stability of PST-01 protease in solutions containing water-soluble organic solvents or alcohols was higher than that in the absence of organic solvent. Furthermore, in general, PST-01 protease was more stable than commercially available proteases, namely, subtilisin Carlsberg, thermolysin, and alpha-chymotrypsin, in the presence of water-soluble organic solvents or alcohols.

Journal Article↗
PubMed1999

Dried green and purple lavers (Nori) contain substantial amounts of biologically active vitamin B(12) but less of dietary iodine relative to other edible seaweeds.

Vitamin B(12) concentrations of dried green (Enteromorpha sp.) and purple (Porphyra sp.) lavers (nori) were determined by both Lactobacillus leichmannii ATCC 7830 microbiological and intrinsic factor chemiluminescence methods. The values determined by using the microbiological method (63.58 +/- 2.90 and 32.26 +/- 1.61 microg/100 g of dry weight) were identical to those found by using the chemiluminescence method (69.20 +/- 2.21 and 25.07 +/- 0.54 microg/100 g of dry weight) in both dried green and purple lavers, respectively. A silica gel 60 thin-layer chromatography of both laver extracts shows that non-coenzyme forms (hydroxo and cyano forms) of vitamin B(12) predominate in both dried lavers. The dried lavers contained lesser amounts of dietary iodine ( approximately 4-6 mg/100 g of dry weight) relative to other seaweeds, suggesting that excessive intake of the dried lavers is unlikely to result in harmful intake of dietary iodine. These results indicate that the dried lavers (nori) are the most excellent source of vitamin B(12) among edible seaweeds, especially for strict vegetarians.

Iodine↗
PubMed1999

Pseudovitamin B(12) is the predominant cobamide of an algal health food, spirulina tablets.

The vitamin B(12) concentration of an algal health food, spirulina (Spirulina sp.) tablets, was determined by both Lactobacillus leichmannii ATCC 7830 microbiological and intrinsic factor chemiluminescence methods. The values determined with the microbiological method were approximately 6-9-fold greater in the spirulina tablets than the values determined with the chemiluminescence method. Although most of the vitamin B(12) determined with the microbiological method was derived from various vitamin B(12) substitutive compounds and/or inactive vitamin B(12) analogues, the spirulina contained a small amount of vitamin B(12) active in the binding of the intrinsic factor. Two intrinsic factor active vitamin B(12) analogues (major and minor) were purified from the spirulina tablets and partially characterized. The major (83%) and minor (17%) analogues were identified as pseudovitamin B(12) and vitamin B(12), respectively, as judged from data of TLC, reversed-phase HPLC, (1)H NMR spectroscopy, ultraviolet-visible spectroscopy, and biological activity using L. leichmannii as a test organism and the binding of vitamin B(12) to the intrinsic factor.

Bacterial Proteins↗
PubMed1999

Corticotropin-releasing factor but not urocortin is involved in adrenalectomy-induced adrenocorticotropin release.

Urocortin, a new corticotropin-releasing factor (CRF)-related peptide, has been reported to have the ability to bind to CRF receptors and to stimulate adrenocorticotropin (ACTH) secretion from the rat anterior pituitary in vivo and in vitro. In this study, we examined the effect of intravenous administration of urocortin-antiserum to investigate the role of endogenous urocortin on ACTH secretion from rat anterior pituitary after adrenalectomy. Male Sprague-Dawley rats, which were maintained in a conscious and undisturbed condition, were administered non-immunized rabbit serum (NRS), CRF-antiserum or urocortin-antiserum at a volume of 1 ml/kg b.w. 15 min before the injection of secretagogues. Synthetic rat urocortin (2 microg/kg B.W.) increased plasma ACTH concentrations by about sixfold the basal concentration. The pretreatment with urocortin-antiserum but not CRF-antiserum abolished the urocortin-induced increase in plasma ACTH concentrations. In adrenalectomized rats, plasma ACTH concentrations were markedly increased at basal conditions, and rapidly reduced after the administration of CRF-antiserum. By contrast, administration of urocortin-antiserum did not alter ACTH secretion induced by adrenalectomy. Our results suggest that endogenous urocortin is unlikely to be involved in ACTH release in adrenalectomized rats.

Adrenalectomy↗
PubMed1999

A chronic, massive thrombus in the right main pulmonary artery: a case report and echocardiographic analysis.

A chronic, large thrombus in the right main pulmonary artery (PA) was detected in a 54-year-old woman with a history of surgical repair of atrial septal defect. Color flow imaging revealed a prominent red signal along the right border of the markedly dilated PA. Pulsed Doppler echocardiography showed that the red signal was caused by flow reversal occurring during systole. According to the physics of blood flow, flow reversal probably represents secondary, helical flow, which may be related to thrombus formation.

Echocardiography↗