Search PubMed⌕ Search

Biomedical subjects

A Itoh

Publications and source records attributed to A Itoh.

269 records · Page 15Linked to original sources
PubMed1980

Structure-activity relationships of antibacterial 6,7- and 7,8-disubstituted 1-alkyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acids.

Previous quantitative and qualitative structure-activity studies in antibacterial monosubstituted 1-ethyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acids prompted us to synthesize the 6,7,8-polysubstituted compounds. In this paper, the preparation and antibacterial activity of the 6,7- and 7,8-disubstituted compounds and their derivatives are described. Among these compounds, 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)quinoline-3-carboxylic acid (34) possessed many significant activities and was more active than oxolinic acid (84) against Gram-positive and Gram-negative bacteria. Structure-activity relationships are discussed.

Anti-Bacterial Agents↗
PubMed1980

Improvement of diabetic symptoms of hereditary diabetic (KK) mice by a single injection with islet-activating protein (IAP).

Islet-activating protein (IAP) prepared from the culture medium of Bordetella pertussis cells was very effective in eliminating diabetic symptoms characteristic of hereditary diabetic KK mice over a long period of time. After a single injection of IAP (5 microgram/kg body wt) into KK mice, the non-fasting concentration of blood glucose was maintained nearly normal over 2 weeks, with a gradual return to the pre-IAP level 30 days later. During this period, glucose tolerance was normalized and only few animals excreted glucose in urine. The second injection of IAP to these diabetic mice caused a more prolonged restoration of normoglycemia. When KK mice had been injected with IAP, they responded to epinephrine and isoproterenol more readily than did ddY mice in increasing plasma insulin and glycerol.

Animals↗
PubMedDate not supplied

Endoscopic diagnosis of pancreatic cancer using intraductal ultrasonography.

BACKGROUND/AIMS: At present developed modalities are not sufficient for detecting early stage pancreatic cancer. We previously reported the clinical usefulness of intraductal ultrasonography in various pancreatobiliary diseases. In the present study we assessed the usefulness of intraductal ultrasonography in diagnosing pancreatic cancer. METHODOLOGY: Thirty-one patients with pancreatic cancer were examined by intraductal ultrasonography. We approached the main pancreatic duct (pancreatic duct-intraductal ultrasonography) in 24 of 31 patients and the bile duct (bile duct-intraductal ultrasonography) in 20 patients with pancreatic cancer. We compared the diagnostic ability of pancreatic duct-intraductal ultrasonography with that of extracorporeal ultrasonography, computed tomography, endoscopic ultrasonography or endoscopic retrograde pancreatography. We examined the usefulness of bile duct-intraductal ultrasonography in diagnosing tumor invasion to the bile duct. RESULTS: Pancreatic duct-intraductal ultrasonography was able to demonstrate a tumor in 22 of 24 patients. Extracorporeal ultrasonography, computed tomography, endoscopic ultrasonography or endoscopic retrograde pancreatography detected tumors in 26, 27, 29, 29 of 31 patients, respectively. In two patients, only intraductal ultrasonography could demonstrate a tumor, which was not detected by any other modalities. We examined bile duct invasion of the tumor according to our grading system. The overall accuracy rate was 90%. No complications were noted in any patients throughout the study period. CONCLUSIONS: Intraductal ultrasonography is useful to diagnose pancreatic cancer, and it is suggested that it should be actively performed after endoscopic retrograde pancreatography.

Aged↗
PubMedDate not supplied

Differentiation of benign and malignant lymph nodes with contrast-enhanced echolymphography using endoscopic ultrasound-guided puncture.

BACKGROUND/AIMS: Although endoscopic ultrasonography is considered the most useful diagnostic modality for the regional staging, the capability of diagnosing lymph node metastasis based on endoscopic ultrasonography images alone is not sufficient. To improve the capability of differential diagnosis of lymph node enlargement, contrast-enhanced echolymphography was performed using endoscopic ultrasonography-guided puncture. METHODOLOGY: Contrast-enhanced echolymphography was performed in 8 metastatic lymph nodes surgically resected from patients with gastrointestinal cancers (in vitro study) and also in 55 patients in whom abdominal lymph node swelling was indicated by endoscopic ultrasonography (in vivo study). Lymph nodes were punctured under real-time endoscopic ultrasonography guidance, and carbon dioxide microbubbles were injected to evaluate echo features before and after microbubbles injection. RESULTS: Contrast-enhanced echolymphography of freshly resected metastatic lymph nodes showed nonhomogeneous echo patterns. In regions demonstrating filling defects detected by contrast-enhanced echolymphography, neoplastic infiltration was pathologically observed. In almost all of the malignant lymph nodes studied in vivo, filling defects and heterogeneous enhancements were observed by contrast-enhanced echolymphography. However, contrast-enhanced echolymphography demonstrated uniform patterns in most of the benign group. The sensitivity, specificity, positive and negative predictive value, and accuracy of differential diagnosis by contrast-enhanced echolymphography were 95.8%, 90.3%, 88.5%, 96.6%, and 92.7%, respectively. CONCLUSIONS: Contrast-enhanced echolymphography is a useful method for help in the differentiation between reactive and malignant alterations of lymph nodes.

Adult↗
PubMedDate not supplied

Digital tomosynthesis imaging of the lung.

We report our preliminary results of pulmonary imaging by digital tomosynthesis, and describe some advantages of these digitally processed longitudinal tomographic images. Digital tomosynthesis of the lung was performed in 60 subjects, including 56 patients with a localized lesion or diffuse disseminated lesions, with a fluororadiographic TV unit with linear tomographic capability, in conjunction with an image processing unit. Dual energy subtraction digital tomosynthesis was also available in our system. Multiple longitudinal tomographs of the lung, which were reconstructed from a single set of tomographic image data, facilitated easy evaluation of the morphology of pulmonary abnormalities together with related broncho-vascular structures located in the same longitudinal plane as the lesion, and were immune from any problem caused by inconsistent depth of respiration. The image quality of the reconstructed tomographs was greatly improved by digital image processing to reduce tomographic blur and enhance image clarity. Dual energy subtraction digital tomosynthesis was effective in clearly showing the size, configuration, and distribution of calcification in the lesion. Digital tomosynthesis provided useful information in making the roentgenologic diagnosis of pulmonary lesions.

Adult↗
PubMedDate not supplied

Efficacy of endoscopic diagnosis and treatment for postoperative biliary leak.

BACKGROUND/AIMS: The purpose of this study was to evaluate the efficacy of endoscopic approaches for the diagnosis and treatment of postoperative biliary leak. METHODOLOGY: Endoscopic retrograde cholangiopancreatography (ERCP) was performed in eight patients with postoperative biliary leak. Of 8 cases, 6 had biliary leak alone (4 cases with a cystic duct leak and 2 cases with a bile duct leak) and 2 cases with a bile duct leak were associated with a bile duct stricture. Endoscopic sphincterotomy (ES) and endoscopic biliary stenting (EBS) were employed in 5 patients and nasobiliary tube drainage (NBD) without ES was performed in 3 patients. RESULTS: In all the patients, ERCP was successfully performed and could demonstrate exact nature and site of postoperative bile duct injuries. In 2 patients with a concomitant bile duct stricture, repetitive endoprosthesis placements were required. The remaining six patients with biliary leak alone were successfully treated by temporary stenting, i.e., ES and EBS (n = 3), and NBD (n = 3). CONCLUSIONS: The patients with postoperative biliary leaks can be successfully diagnosed by ERCP and treated by temporary endoscopic methods. Among various endoscopic treatments, NBD alone appears to be preferable in treating patients with small bile leaks. However, cases with a concomitant bile duct stricture were intractable and required longer period of stenting.

Adult↗