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Biomedical subjects

T Takeuchi

Publications and source records attributed to T Takeuchi.

At least 667 records · Page 37Linked to original sources
PubMed1996

Heliquinomycin, a new inhibitor of DNA helicase, produced by Streptomyces sp. MJ929-SF2 I. Taxonomy, production, isolation, physico-chemical properties and biological activities.

Heliquinomycin was isolated as a part of a program designed to find inhibitors of DNA helicase from microbial sources. It was purified from the culture broth of Streptomyces sp. MJ929-SF2 by solvent extraction and serial chromatographies of centrifugal partition chromatography, Sephadex LH-20 and Capcell Pak C18 (HPLC). The isolated red powder was analyzed to have the molecular formula of C33H30O17. It inhibited partially purified DNA helicase from HeLa cell in a non-competitive manner with the inhibition constant (Ki) of 6.8 mM. Heliquinomycin exhibited biological activity against microorganisms including MRSA, and cultured cell lines.

Animals↗
PubMed1996

Poststatin, a new inhibitor of prolyl endopeptidase. V. Endopeptidase inhibitory activity of poststatin analogues.

Thirty analogues of poststatin were synthesized, and their inhibitory activities against prolyl endopeptidase, human leukocyte elastase and cathepsin B were measured. The alpha-ketone was essential and the S configuration was preferable to the R configuration in the beta-substituted-beta-amino-alpha-oxopropionic acid moiety of poststatin analogues for endopeptidase inhibitory activity. The analogue in which the D-leucine residue of poststatin was replaced by L-leucine showed strong inhibitory activity to cathepsin B. Introduction of an aromatic group into the P4 position and proline into the P2 position increased inhibitory activity to elastase. Benzyloxycarbonyl-L-homophenylalanyl-(RS)- 3-amino-2-oxovaleryl-D-leucyl-L-valine was about 6 times more active to prolyl endopeptidase than natural poststatin.

Cathepsin B↗
PubMed1996

Poststatin, a new inhibitor of prolyl endopeptidase. VI. Endopeptidase inhibitory activity of poststatin analogues containing pyrrolidine ring.

Several pyrrolidine-containing analogues of poststatin were synthesized and examined for their inhibitory activity against prolyl endopeptidase and cathepsin B in vitro. Replacement of the postine residue with 2-oxo-2-(2-pyrrolidinyl)acetic acid increased the selectivity and inhibitory activity against prolyl endopeptidase. Benzyloxycarbonyl-L-phenylalanyl-(S)-2-oxo-2- (2-pyrrolidinyl)acetyl-D-phenylalanine was about 46 times as active to propyl endopeptidase as natural poststatin.

Cathepsin B↗
PubMed1996

Poststatin, a new inhibitor of prolyl endopeptidase. VII. N-cycloalkylamide analogues.

Poststatin analogues containing (S)-2-oxo-2-(2-pyrrolidinyl)acetyl moiety in P1 were synthesized and examined for their inhibitory activity against prolyl endopeptidase and cathepsin B in vitro. Introduction of non-peptidyl cycloalkylamine component in P1, was effective and P3-acyl groups must be widely modifiable for prolyl endopeptidase inhibition. Acyl-L-phenylalanyl-(S)-2-oxo-2-(2-pyrrolidinyl)acetyl-cycloalkylamid e type compounds showed IC50 value of nano to subnano g/ml as prolyl endopeptidase inhibitor and were shown no significant inhibitory activities against cathepsin B, a cysteine protease.

Cathepsin B↗
PubMed1996

[A case of pulmonary dirofilariasis].

A 41-year-old man was admitted to the hospital for detailed evaluation of chronic hepatitis C. A nodular shadow (15 x 15 mm) was detected in the left middle lung field on a chest X-ray film. Roentgenologic, cytologic, and bronchial endoscopic examinations resulted in no definitive diagnosis. To rule out a malignant tumor the left lung was partially resected (S6). Histological examination of the resected specimen revealed Dirofilaria worms in a necrotic mass. In most cases of pulmonary dirofilariasis, thoracotomy is done to confirm the diagnosis. Recently, however, antibodies against Dirofilaria have been detected by immunologic methods and have been used to help make the diagnosis in some cases. A less invasive procedure, such as a reliable immunologic test or a technique for thoracoscopic resection, would be very useful in cases of this benign condition.

Adult↗
PubMed1996

Single application extracorporeal shock wave lithotripsy is the first choice for patients with pancreatic duct stones.

OBJECTIVES: We performed extracorporeal shock wave lithotripsy (ESWL) as the treatment of first choice on 32 chronic pancreatitis patients with main pancreatic duct (MPD) stones prospectively to establish more convenient and safer treatment. METHODS: All patients were treated in a prone position, and shock waves were discharged from the ventral side. ESWL was performed once or twice a week, and no other treatments before ESWL had been applied. RESULTS: Disintegration of all MPD stones to 3 mm or less in diameter could be achieved in all treated patients. Complete clearance of the stones was obtained in 24 patients (75%) without the necessity of endoscopic extraction of fragments. Reduction of MPD diameters after ESWL was statistically significant (p < 0.01). Epigastric and/or back pain complaints before ESWL were completely alleviated in 79% (periods of follow-up: 16-63 months, mean 44), and the pancreatic exocrine function also improved in 61%. No severe complications occurred in any of the patients. CONCLUSIONS: ESWL, which is comparatively easy to perform, is a safe and efficient approach that changes endoscopy's status as an indispensable pretreatment. Therefore, ESWL can be recommended as the first choice treatment for patients with chronic pancreatitis accompanied by MPD stones that should be tried before consideration of either surgical or endoscopic procedures.

Adult↗
PubMed1996

[Bronchial asthma complicated by myasthenia gravis].

A 52-year-old woman had a 14-year history of stridor attacks. Pulmonary function tests revealed reversible airway obstruction, and bronchial asthma was diagnosed. She also has bilateral ptosis, diplopia, and moderate weakness of all four limbs; a positive edrophonium test confirmed the diagnosis of myasthenia gravis. Although the parasympathetic system plays an important role in the regulation of bronchial tone, in this patient the edrophonium test did not provoke an asthmatic attack or exacerbate pulmonary function, except for increases in sputum production and in frequency of cough. The general weakness was usually worse in the afternoon. The decrease in grip strength and the shortening of arm elevation time also occurred after asthma attacks, which means that general muscle fatigue was caused by the work of breathing. Furthermore, dyspnea increased and pulmonary function worsened when an anti-cholinesterase inhibitor was discontinued, probably because of respiratory muscle weakness. Accordingly, the clinical status of bronchial asthma seemed to change in parallel with that of the myasthenia gravis.

Asthma↗
PubMed1996

[Necessity for searching for cerebral aneurysm in thunderclap headache patients who show no evidence of subarachnoid hemorrhage: investigation of 8 minor leak cases on operation].

The study included 562 patients with headache who visited our clinic from January 1988 to December 1993. In these patients, the possibility of subarachnoid hemorrhage was denied from CT findings and color of cerebrospinal fluid by lumbar puncture. Cerebral aneurysm was found in 52 out of 562 patients (9.3%), and minor leak was found during 46 surgery cases in 8 patients with cerebral aneurysm. These 8 patients (32-51 years old, 5 males and 3 females, period from onset to hospital visit; 1-6 days) were examined concerning characteristics of headache and concomitant symptom, cerebrospinal fluid and operative findings. Headache attack occurred at rest in 6 patients (75%) and suddenly in all patients. It continued over 24 hours in 7 patients (87.5%). All patients felt that they had never experienced such a headache. Pulsating headache was observed in 5 patients (62.5%). Nausea and vomiting were complications in all patients. The site of headache was in the forehead region, and circumorbital pain was a complication in four patients. Six patients (75%) had unilateral pain, and 5 patients (62.5%) had headache at the same side as the cerebral aneurysm. Increase of cell count ( > or = 10/mm3) in cerebrospinal fluid was found in 4 patients (50%). In all cases, lymphocytes were dominant. Arachnoid adhesion and hypertrophy with hemorrhage were found during surgery in 4 patients (50%). In these patients, the period from onset to surgery (average 16.5 days) was longer than that of the patients with hemorrhage alone (average 6 days). The site of the hemorrhage was located in the cistern of the cerebral aneurysm in all cases. In patients suffering sudden headache, screening for cerebral aneurysm should be thoroughly performed though early findings on CT and cerebrospinal fluid indicated no abnormalities.

Adult↗
PubMed1996

[Results of cataract surgery in patients with uveitis].

PURPOSE: Extraction of cataracts with posterior chamber intraocular lens (PC-IOL) implantation has been attempted with some encouraging results in uveitis having minor intensity. However, the number of operated patients is very limited. We present the results in patients having more important intensity of uveitis. MATERIALS AND METHODS: The authors studied 28 eyes in 20 patients who underwent cataract extraction as a complication of uveitis. RESULTS: All the operations were accomplished by phacoemulsification and aspiration (PER) with posterior chamber lens implanted in 23 eyes. Etiologic diagnosis included 8 sarcoidosis, 5 Behçet, 3 Vogt-Koyanagi-Harada syndrome and 12 other aetiologies. Eighty percent of patients obtained visual acuity better than 0.6 postoperatively. Postoperative complications were not severe. CONCLUSIONS: The indication of PC-IOL could be given to cataracts in chronic uveitis if the patients are older than 35 years and there are no uveal inflammatory signs at least 3 months prior to considered implantation.

Adult↗
PubMed1996

Human brain disturbance by methylmercury poisoning, focusing on the long-term effect on brain weight.

The long-term effects of the initial methylmercury exposure in the Minamata area were examined, with focus on brain weight. Comparisons were made between the brain weights of methylmercury-contaminated persons in the Minamata area (cases) and those of Japanese who suffered sudden or accidental death without brain disease (controls). Since over thirty years have passed since the outbreak of Minamata disease, subjects aged 30 or over at death were included in the analysis. The total number of cases was 417 (273 males, 144 females) and that of controls was 2,934 (2,174 males, 760 females). The data suggest that the brain weights from Minamata cases were reduced by 80 to 200g as compared to the controls. These results may indicate that methylmercury exposure led to a decrease of nerve cells (single cell necrosis), so-called "thinning out", in the brain cortex.

Adult↗
PubMed1996

Biopsy of labial salivary glands and lacrimal glands in the diagnosis of Sjögren's syndrome.

OBJECTIVE: To determine the diagnostic value in Sjögren's syndrome (SS) of evaluating the presence of focal adenitis in labial salivary gland (LSG) and lacrimal gland (LG) biopsy specimens. METHODS: We studied 105 cases with suspected SS and performed biopsies prospectively. The diagnostic criteria of Fox, et al were followed. The Chisholm-Mason grading standard and Greenspan focus score were used for evaluation. RESULTS: Epimyoepithelial islands and severe lymphocyte infiltration with germinal centers were observed only in LG biopsy specimens (5.9 and 3.5%, respectively). The lymphocytic focus scores of LG (2.5 +/- 2.1/4 mm2) were significantly higher than those of LSG specimens (1.3 +/- 1.1/4 mm2) in 23 cases with both biopsy results (p < 0.05). Six of the 32 LSG biopsies were normal while their LG biopsies were significantly higher. Conversely, 5 of the 32 LG biopsies were aided by corresponding LSG biopsies, since in LG biopsies no glandular tissue was obtained. Evaluation of both specimens for the same patient was significantly more effective in diagnosing SS than using either specimen alone (p < 0.01). CONCLUSION: LG biopsy specimens have a more evident histopathology than LSG biopsy specimens. We recommend that both LSG and LG biopsies be performed in patients with suspected SS to reduce false negative results and improve diagnostic accuracy.

Biopsy↗
PubMed1996

Decreased reflex tearing is associated with lymphocytic infiltration in lacrimal glands.

OBJECTIVE: To investigate whether reflex tearing measured by the Schirmer test with nasal stimulation is better correlated with lymphocytic infiltration of the lacrimal gland and is thus a more appropriate test for Sjögren's syndrome (SS). METHODS: 272 patients with dry eye (age 55.5 +/- 13.5 years) with regular Schirmer test results < 10 mm were recruited for the study. They were divided into 2 groups depending on the results of the Schirmer test with nasal stimulation. 24 age and sex matched patients from each group were selected for lacrimal gland biopsy and 10 patients for salivary gland biopsy, and the levels of systemic autoantibodies and degrees of ocular surface staining and lymphocytic infiltration of the lacrimal and salivary glands were compared. RESULTS: Of the 272 patients, 187 (68.8%) had good reflex tearing (GT) and 85 (31.2%) had poor reflex tearing (PT). There were no significant differences in the age or sex of the 2 groups. Lymphocytic infiltration of the lacrimal gland was observed in 7 GT cases and 22 PT cases out of 24 cases. Lymphocytic infiltration of the salivary gland was also higher in the PT (6 of 10) than the GT group (2 of 10). CONCLUSION: Evaluation of reflex tearing by the Schirmer test with nasal stimulation identifies 2 groups of patients with dry eye. Those with poor reflex tearing were more likely to have autoantibodies and lymphocytic infiltration of the exocrine glands consistent with SS.

Adult↗
PubMed1996

[Gore-tex covering of ultraflex stent and its usefulness for malignant esophageal stenosis: preliminary clinical results].

Malignant esophageal stenoses develop esophagorespiratory fistulae or perforations so frequently that esophageal stents must be required. We devised a covered stent with a thin Gore-Tex sheet and a nitinol stent system, Ultraflex, without increasing the size of the introducer assembly. Nine patients with malignant esophageal stenoses, including seven patients with perforation or fistulation, were carefully treated with the covered stent. All stent deployments were successfully carried out under fluoroscopic guidance. The average time required for full self-expansion was two weeks. The average grade of dysphagia improved from 3.7 to 1.2. Clinical symptoms due to esophagorespiratory fistulae were improved in three of four patients. No clinical or technical complications, such as migration, were observed, but a fistula developed at the bare site of the stent. This covering method for the flexible stent was simple and safe, and was considered to be useful in the treatment of malignant esophageal stenosis.

Adenocarcinoma↗