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Yoshida M, Tsukamoto Y, Niwa Y, Goto H, Hase S, Hayakawa T, Okamura S. Endoscopic assessment of invasion of colorectal tumors with a new high-frequency ultrasound probe. Gastrointest Endosc 1995; 41:587-92. [PMID: 7672554 DOI: 10.1016/s0016-5107(95)70196-6] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The present study was carried out to clarify the usefulness of and problems associated with a new ultrasound probe in the assessment of invasion of colorectal tumors. Normal colorectal wall of 23 resected specimens from colorectal cancer cases was examined in vitro with the probe. Fifty-one patients with colorectal carcinoma and 16 patients with rectal carcinoid tumor were presurgically examined using the probe via the biopsy channel of a conventional colonoscope. After endoscopic and ultrasonographic examination, 27 patients underwent endoscopic resection and 40 underwent surgical resection. The ultrasonographic findings were compared with histologic findings in all cases. Carcinomas and carcinoid tumors were visualized as an echo-poor region with the probe. The overall accuracy rate for depth of invasion was 76% (39/51) for colorectal cancer. The accuracy rates for tumors limited to the mucosa and tumors invading the submucosa were 83% and 90%, respectively; these rates were higher than those for tumors invading the muscularis propria (50%) and beyond the muscularis propria (73%). In all 16 cases of carcinoid tumor, the depth of invasion was accurately shown to be limited to the submucosa. This probe is useful to assess invasion of colorectal tumors, especially small and flat lesions limited to the mucosa or submucosa.
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Tsukamoto Y, Moriya R, Nagaba Y, Morishita T, Izumida I, Okubo M. Effect of administering calcium carbonate to treat secondary hyperparathyroidism in nondialyzed patients with chronic renal failure. Am J Kidney Dis 1995; 25:879-86. [PMID: 7771484 DOI: 10.1016/0272-6386(95)90570-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We administered calcium carbonate orally to determine its safety and efficacy in treating nondialyzed patients with mild to moderate renal failure and secondary hyperparathyroidism. Twenty patients with chronic renal failure (creatinine clearance levels ranging from 7.9 to 42.7 mL/min) participated in this study. After a 6-month control period, 3 g calcium carbonate was administered daily for 6 months. We studied the effect for another 6 months after discontinuation of the regimen. We found that serum-intact parathyroid hormone was suppressed from 183 +/- 149 pg/mL to 85 +/- 61 pg/mL (P < 0.05) by treatment. This suppression was achieved with no increase in serum concentrations of 1,25(OH)2D3. Serum phosphorus levels decreased from 3.4 +/- 0.7 to 3.0 +/- 0.7 mg/dL (P < 0.01) and Ca2+ concentration increased significantly from 2.40 +/- 0.12 mEq/L to 2.57 +/- 0.08 mEq/L (P < 0.001) at 6 months. These changes were reversed after the 6-month period of withdrawal from calcium carbonate. Deterioration of renal function was not exacerbated by the therapy. Calcium carbonate administration also suppressed the serum concentrations of alkaline phosphatase and osteocalcin, indicating that improvement of hyperparathyroid bone disease is possible without a vitamin D3 supplement at an earlier stage of renal failure. Thus, administration of 3 g oral calcium carbonate daily was highly effective in treating secondary hyperparathyroidism in patients with mild to moderate renal failure.
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Abstract
Twenty patients with acute, displaced, radial neck fractures were treated by percutaneous reduction with a periosteal elevator. In all cases acceptable radiographic reduction was achieved, and the reduction position was maintained on serial x-ray examinations with a mean observation period of 3 years. Clinical results were satisfactory in all but one case with slightly limited elbow extension.
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Tanaka K, Kawasaki H, Kurata K, Aikawa Y, Tsukamoto Y, Inaba T. T-614, a novel antirheumatic drug, inhibits both the activity and induction of cyclooxygenase-2 (COX-2) in cultured fibroblasts. JAPANESE JOURNAL OF PHARMACOLOGY 1995; 67:305-14. [PMID: 7650864 DOI: 10.1254/jjp.67.305] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
To elucidate the mechanism for the selective inhibition of prostaglandin E2 (PGE2) production in inflammatory tissue by T-614 (3-formylamino-7-methylsulfonylamino-6-phenoxy-4H-1-benzopyran-4-o ne), its effects on both the activity and the induction of cyclooxygenase (COX)-2 were investigated in vitro. T-614 inhibited the activity of purified COX-2 enzyme (IC50: 7.7 micrograms/ml), but was inactive against both COX-1 activities of microsomal and purified enzymes (IC50: > 300 micrograms/ml). On the other hand, when the inhibition of PGE2 production by T-614 was examined in the cultured fibroblasts stimulated with bradykinin, T-614 at 1 microgram/ml or less inhibited PGE2 release more effectively than that in the above cell-free system. Therefore, we examined which of the COX enzymes was expressed in bradykinin-stimulated fibroblasts by using both the reverse transcriptase-polymerase chain reaction (RT-PCR) and Northern blot analyses. As a result, COX-1 mRNA was constitutively expressed in the cells, whereas COX-2 mRNA was not detected without stimulation with bradykinin, but was expressed within 30 min when stimulated. Furthermore, it was found that the addition of T-614 reduced the COX-2 mRNA levels in 30 min after stimulation. These studies suggest that at least some of inhibitory effects of T-614 on prostanoids production are mediated by the synergy of the inhibition of COX-2 activity and the inhibition of induction, and such an action of T-614 may explain the pharmacological properties of this drug.
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Ohmiya N, Ito M, Ohbayashi M, Arisawa T, Goto H, Tsukamoto Y, Hayakawa T, Asai J. Two phenotypically distinct B lymphocytes (IgMhighIgDlow and IgMlowIgDhigh) in chronic gastric ulcer in the rat. Clin Exp Immunol 1995; 100:151-6. [PMID: 7697915 PMCID: PMC1534279 DOI: 10.1111/j.1365-2249.1995.tb03617.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We determined the kinetics and phenotypes of infiltrating B cells in gastric ulcer in the rat induced by gastric injection of acetic acid (day 0). Few B cells were found in the lesion in the early stages of ulceration. On day 40, two kinds of B cells with phenotypes of IgMhighIgDlowOX33 (CD45)+OX19 (CD5)- and IgMlowIgDhighOX33 (CD45)+OX19 (CD5)- were scattered in the granulation tissue of open ulcers, but not in the healed scar tissue. On day 180, those two kinds of B cells formed primary follicles in the granulation tissue of open ulcers, but were absent from the healed scar tissue. The IgMhighIgDlowOX33 (CD45)+OX19 (CD5)- B cell was considered to be identical to the marginal zone B cell of rat spleen. This phenotype of B cell might be associated with inflammatory process in chronic gastric ulcer.
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Segawa K, Niwa Y, Arisawa T, Kato T, Goto H, Hamajima E, Shimodaira M, Miyata A, Ohmiya N, Tsukamoto Y. Incidence of peptic ulcer in men is inversely correlated with blood pressure: study in an apparently healthy Japanese population. Am J Gastroenterol 1995; 90:399-402. [PMID: 7872277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To study the role of autonomic nervous innervation in the etiology of peptic ulcer, we investigated the blood pressure in patients with peptic ulcer. METHODS In 100,085 Japanese adults who were undergoing health screening examinations, including barium meal study, there were endoscopic evaluation-confirmed diagnoses of gastric ulcer in 769 cases and of duodenal ulcer in 344 cases. The blood pressure in those patients was compared with that in 57,208 normal Japanese controls with no gastrointestinal abnormalities, as confirmed by barium meal study. RESULTS The blood pressure of younger and middle-aged men with gastric and duodenal ulcer were lower than those of normal control men. In women, except for the diastolic pressure of those in their 50s, the blood pressure in patients with peptic ulcer and normal controls did not differ significantly. The incidence of duodenal ulcer or of gastric ulcer in men was inversely related to the systolic and diastolic pressure. No definite relationship in this respect was seen in women. CONCLUSIONS An inverse relationship was observed between the occurrence of peptic ulcer and the blood pressure level in Japanese men, but not in women. The relationship may be mediated by an inhibitory effect of the sympathetic nervous system on ulcer formation in hypertensive subjects. The reason for the sex difference in this respect is unknown.
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Ooiwa T, Goto H, Tsukamoto Y, Hayakawa T, Sugiyama S, Fujitsuka N, Shimomura Y. Regulation of valine catabolism in canine tissues: tissue distributions of branched-chain aminotransferase and 2-oxo acid dehydrogenase complex, methacrylyl-CoA hydratase and 3-hydroxyisobutyryl-CoA hydrolase. BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1243:216-20. [PMID: 7873565 DOI: 10.1016/0304-4165(94)00061-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
To clarify the valine catabolism, the activities of principal enzymes in its catabolic pathway, branched-chain aminotransferase, branched-chain 2-oxo acid dehydrogenase complex, methacrylyl-CoA hydratase and 3-hydroxyisobutyryl-CoA hydrolase, were measured using canine tissues. After killing of beagle dogs, tissues (liver, pancreas, kidney, heart, skeletal muscle and mucosae of digestive organs such as stomach, small intestine and colon) were removed and immediately frozen. Branched-chain aminotransferase activity in liver was the lowest among the tissues measured. In contrast, the activities of branched-chain 2-oxo acid dehydrogenase complex in liver as well as in kidney were relatively high and the enzyme complex activities were markedly low in small intestine and skeletal muscle. The activities of methacrylyl-CoA hydratase and 3-hydroxyisobutyryl-CoA hydrolase were relatively high in all tissues, suggesting that a cytotoxic intermediate, methacrylyl-CoA, is immediately degraded to non-toxic compounds, 3-hydroxyisobutyrate and free CoA. These findings suggest that the consumption of branched-chain amino acids in the absorption site (small intestine) is suppressed in order to supply them to the whole body, in particular to skeletal muscle and that skeletal muscle might act as a storage of gluconeogenic amino acids. The high capacity to dispose methacrylyl-CoA produced in the valine catabolism is suggested to play an important role in protecting cells against the toxic effects of methacrylyl-CoA.
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Ohtani H, Tsukamoto Y, Sakoda Y, Hamaguchi H. Fluorescence spectra of bacteriorhodopsin and the intermediates O and Q at room temperature. FEBS Lett 1995; 359:65-8. [PMID: 7851532 DOI: 10.1016/0014-5793(94)01440-c] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
An unequivocal answer is given to the question of why the reported fluorescence spectra of bacteriorhodopsin (bR568) have been different from one another. The inconsistency is shown to arise from the accumulation of the fluorescent intermediates O and Q (KN) by cw excitation light. Their fractions in the photo-stationary states depend on the excitation power and the suspension pH. We report the intermediate-free fluorescence spectrum of bR568 obtained with a weak excitation source (632.8 nm, 5.3 x 10(15)-1.9 x 10(16) photons cm-2.s-1) and a near-IR sensitive intensified photodiode array system. The fluorescence maxima of the spectra, F(lambda) and f(nu), are located at 755 +/- 10 nm and 12700 +/- 200 cm-1, respectively. The spectrum of O is identical to that of the deionized purple membrane bR605 (Fmax = 750 +/- 5 nm, fmax = 13,000 +/- 100 cm-1). Q (KN) exhibits a blue-shifted spectrum more than that of bR568 (Fmax < 720 nm, fmax > 13,400 cm-1).
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Tsukamoto Y. Pathophysiology and treatment of secondary hyperparathyroidism in patients with chronic renal failure. Nephrol Dial Transplant 1995; 10 Suppl 3:22-4. [PMID: 7494609 DOI: 10.1093/ndt/10.supp3.22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Following four etiologies are considered as the possible reason for secondary hyperparathyroidism in the previous reports. First, a decreased serum concentration of 1,25(OH)2D3 directly stimulates PTH secretion. Second, hypocalcemia directly stimulates PTH secretion which is independent of 1,25(OH)2D3 action. Third, the presence of decreased calcemic response to PTH. Fourth, there is a strong possibility that hyperphosphatemia indirectly and/or directly may stimulate PTH secretion. The treatment of secondary hyperparathyroidism should be modified according to the stage of uremia. Excess suppression of PTH secretion could cause an adynamic bone disease. Early start of the treatment would be beneficial to prevent the bone from the development of PTH resistance.
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Tsukamoto Y, Goto H, Hase S, Niwa Y, Arisawa T, Hayakawa T, Yoshikane H. Endosonographic evaluation of the quality of ulcer healing induced by proton pump inhibitors. J Clin Gastroenterol 1995; 20 Suppl 2:S40-3. [PMID: 7594337 DOI: 10.1097/00004836-199506002-00011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We studied 26 gastric ulcer patients who were treated with a proton pump inhibitor to evaluate the quality of ulcer healing using endoscopic ultrasonography (EUS), and we examined the relationship between ulcer recurrence and contraction demonstrated on ulcer echoes (study I). The effect of lansoprazole versus an H2-receptor antagonist on the contraction of ulcer echoes (study II) was also investigated. In study I, gastric ulcer patients who demonstrated early healing by endoscopy often had shallow Ul-II or Ul-III ulcers and small cross-sectional areas on ulcer echoes. The early contraction on ulcer echo was associated with lower rates of ulcer relapse, and might therefore be indicative of a good quality of healing. In study II, the ulcer contraction rate after 8 weeks of treatment with lansoprazole was 71.8%, significantly higher than that achieved with H2-receptor antagonists. However, the mean cross-sectional area of gastric ulcer after 8 weeks of treatment with lansoprazole was 113.9 mm2. In conclusion, although lansoprazole was suitable for initial therapy in peptic ulcer patients, the quality of ulcer healing based on EUS findings did not appear to be adequate in patients treated for the short periods of time in this study.
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Yoshikane H, Tsukamoto Y, Niwa Y, Goto H, Hase S, Maruta S, Shimodaira M, Miyata A. The coexistence of esophageal submucosal tumor and carcinoma. Endoscopy 1995; 27:119-23. [PMID: 7601022 DOI: 10.1055/s-2007-1005645] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The coexistence of esophageal submucosal tumor and carcinoma has been reported only in very few cases up to now, and the relationship between them is unclear. To elucidate the incidence and the pathogenesis of their coexistence, endoscopy and endoscopic ultrasonography (EUS) were sequentially performed in 95 patients who were suspected of having a submucosal tumor of the esophagus. EUS revealed 83 submucosal tumors and 12 cases of extraluminal compression. Two cases of esophageal carcinoma were observed in the series. In one patient, intraepithelial carcinoma was present on a leiomyoma originating in the muscularis mucosae, and in the other patient, multiple superficial carcinomas were presented.
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Ohshima Y, Tsukamoto Y, Naitoh Y, Hirooka Y, Furukawa T, Nakagawa H, Hayakawa T. Function of the minor duodenal papilla in pancreas divisum as determined by duodenoscopy using indigo carmine dye and a pH sensor. Am J Gastroenterol 1994; 89:2188-91. [PMID: 7977239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES The objective of this study was to evaluate the function of the minor duodenal papilla and to investigate the relationship between the history of acute pancreatitis and individual dorsal pancreatogram findings and the minor papilla function in pancreas divisum. METHODS Eight of the 21 patients with PD diagnosed by endoscopic retrograde cholangiopancreatography had a history of acute pancreatitis (group A), and 13 patients did not (group B). The reaction of pancreatic juice excreted via the minor papilla was evaluated after intravenous administration of secretin, by observing the repulsion of indigo carmine dye scattered on the surface of the minor papilla. RESULTS The function of the minor papilla was classified into two types. In 12 patients, all of the pigment on the minor papilla was repelled within 5 min of secretin administration (type I), and in the remaining nine patients it was not (type II). After secretin administration, the pH of the minor papilla surface in type I was significantly higher than that in type II. There was no significant difference between the type I and type II patients in exocrine pancreatic function, as evaluated by a BT-PABA test. In the group A patients, the rate of occurrence of dorsal duct dilation (including changes of the terminal shape) was significantly greater than in the group B patients. The function of the minor papilla in the group A patients was significantly worse than in the group B patients. Outflow obstruction of pancreatic group B patients. Outflow obstruction of pancreatic juice, i.e., "relative stenosis of the minor papilla," was considered to be present in the patients with type II papilla, and, therefore, the patients with type II papilla might suffer from acute pancreatitis resulting from poor drainage of pancreatic juice and excessive pressure in the dorsal duct. CONCLUSION The finding that patients with PD have one of two types of minor papilla will be useful for understanding the condition and selecting the therapeutic plan for individual patients.
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Furukawa T, Tsukamoto Y, Naitoh Y, Hirooka Y, Hayakawa T. Differential diagnosis between benign and malignant localized stenosis of the main pancreatic duct by intraductal ultrasound of the pancreas. Am J Gastroenterol 1994; 89:2038-41. [PMID: 7942732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Our objectives in this study were to differentiate between pancreatic cancer (PC) and chronic pancreatitis (CP) in cases with localized stenosis of the main pancreatic duct (MPD) by an intraductal ultrasound (IDUS) probe which were detected on pancreatogram. METHODS We inserted the IDUS probe (30 MHz) into the MPD in all cases and scanned the stenotic site in 23 of 26 cases (88.5%) in vivo. In all 26 patients, the stenotic site was surgically resected, and IDUS scanning was also performed on the resected specimens. Findings from IDUS were compared with those from histology. The diagnostic ability of IDUS was compared with that of endoscopic ultrasonography (EUS), computed tomography (CT), and endoscopic retrograde pancreatography (ERP). RESULTS The IDUS images of localized stenosis were classified into two types: type I showed an echorich area surrounded by an echo-poor margin and was found in 14 PC patients and one CP patient; type II showed a ring-like echolucent band surrounded by a fine reticular pattern and was found in 11 CP. Therefore, we considered that type I tended to be characteristic of PC, whereas type II tended to be characteristic of CP. Sensitivities of EUS, CT, ERP, and IDUS in diagnosing PC were 92.9% (13/14), 64.3% (9/14), 85.7% (12/14), and 100% (14/14), respectively. Specificities of EUS, CT, ERP, and IDUS were 58.3% (7/12), 66.7% (8/12), 66.7% (8/12), and 91.7% (11/12), respectively. CONCLUSIONS IDUS examination might be useful in the diagnosis of patients with localized stenosis of the MPD, but its precise role in the diagnostic work-up of patients with pancreatic diseases remains to be determined by further studies.
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Kato T, Tsukamoto Y, Naitoh Y, Mitake M, Hirooka Y, Furukawa T, Hayakawa T. Ultrasonographic angiography in gallbladder diseases. Acta Radiol 1994; 35:606-13. [PMID: 7946686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Ultrasonographic (US) angiography was performed by sonographic examination with injection of carbon dioxide microbubbles through a catheter following conventional angiography in 41 patients with various gallbladder diseases. Three enhancement patterns were found; strong enhancement in the lesion from the periphery to the center was noted in patients with adenocarcinoma and benign polyp (type I), irregular partial enhancement at the margins of the lesion in those with adenosquamous carcinoma (type II), and internal regular enhancement in those with chronic cholecystitis, xanthogranulomatous cholecystitis and adenomyomatosis (type III). Pseudopolypoid lesion such as gallbladder debris showed no enhancement. US angiography may be useful in the differential diagnosis of gallbladder diseases, especially to differentiate the wall thickening type of gallbladder carcinoma from chronic cholecystitis or adenomyomatosis, and the pseudopolypoid lesion and fundal type of adenomyomatosis from benign polyp or polypoid-type carcinoma.
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Kato T, Tsukamoto Y, Naitoh Y, Mitake M, Hirooka Y, Furukawa T, Hayakawa T. Ultrasonographic Angiography in Gallbladder Diseases. Acta Radiol 1994. [DOI: 10.3109/02841859409173331] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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216
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Nakayama S, Tsukamoto Y, Yamamoto M, Hosomi H, Saitoh Y. Non invasive analysis of pancreatic and systemic hemodynamics in dogs with acute pancreatitis. PATHOPHYSIOLOGY 1994. [DOI: 10.1016/0928-4680(94)90702-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Calkins DJ, Schein SJ, Tsukamoto Y, Sterling P. M and L cones in macaque fovea connect to midget ganglion cells by different numbers of excitatory synapses. Nature 1994; 371:70-2. [PMID: 8072528 DOI: 10.1038/371070a0] [Citation(s) in RCA: 151] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Visual acuity depends on the fine-grained neural image set by the foveal cone mosaic. To preserve this spatial detail, cones transmit through non-divergent pathways: cone-->midget bipolar cell-->midget ganglion cell. Adequate gain must be established along each pathway; crosstalk and sources of variation between pathways must be minimized. These requirements raise fundamental questions regarding the synaptic connections: (1) how many synapses from bipolar to ganglion cell transmit a cone signal and with what degree of crosstalk between adjacent pathways; (2) how accurately these connections are reproduced across the mosaic; and (3) whether the midget circuits for middle (M) and long (L) wavelength sensitive cones are the same. We report here that the midget ganglion cell collects without crosstalk either 28 +/- 4 or 47 +/- 3 midget bipolar synapses. Two cone types are defined by this difference; being about equal in number and distributing randomly in small clusters of like type, they are probably M and L.
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Maruta S, Tsukamoto Y, Niwa Y, Goto H, Hase S, Yoshikane H, Hayakawa T. Evaluation of upper gastrointestinal tumors with a new endoscopic ultrasound probe. Gastrointest Endosc 1994; 40:603-8. [PMID: 7988827 DOI: 10.1016/s0016-5107(94)70262-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Itoh A, Tsukamoto Y, Naitoh Y, Hirooka Y, Furukawa T, Kato T, Kuroiwa M, Hayakawa T. Intraductal ultrasonography for the examination of duodenal papillary region. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 1994; 13:679-684. [PMID: 7933043 DOI: 10.7863/jum.1994.13.9.679] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The purpose of this study was to provide basic criteria for interpreting images of the normal duodenal papillary region obtained by intraductal ultrasonography at the frequency of 20 MHz. Our in vitro examination of autopsy specimens from 15 patients revealed that the images could be classified into three patterns according to the spatial relationships between the duodenal muscularis propria and the bile duct, or the common duct. Oddi's muscle was clearly demonstrated surrounding the mucosa of the bile duct or the common duct, which was visualized as a hypoechoic layer. The images obtained using in vivo examination of 60 patients with pancreato-biliary disease via either the percutaneous or the peroral approach were similar to the images obtained in vitro. In eight patients with cancer of the papilla of Vater, the tumor was demonstrated clearly on intraductal sonograms. The intraductal imaging features of the normal papillary region were clarified, and the clinical usefulness of this technique in the evaluation of the tumor extent in patients with cancer of the papilla of Vater is suggested.
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Mabuchi K, Tsukamoto Y, Obara T, Yamaguchi T. The effect of additive hyaluronic acid on animal joints with experimentally reduced lubricating ability. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1994; 28:865-70. [PMID: 7983085 DOI: 10.1002/jbm.820280805] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A series of in vitro experiments demonstrated a clear effect of additive hyaluronic acid (HA) on animal joints with experimentally reduced lubricating ability. Eleven canine hip joints were utilized and the experimental conditions tested were: i) intact joints, ii) after washing the joint surfaces, and iii) after adding 1% HA to them. The frictional coefficient of every joint increased after washing and subsequently decreased after adding HA. The mean values were 0.007 (SD 0.004) on the intact joints, 0.020 (SD 0.009) after washing, and 0.013 (SD 0.005) after the addition of HA. The differences between the three values of frictional coefficients were shown to be statistically significant (p < 0.01).
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Yoshikane H, Tsukamoto Y, Niwa Y, Goto H, Hase S. Sequential observation of gastric ulcer healing by endoscopic ultrasonography. Scand J Gastroenterol 1994; 29:665-70. [PMID: 7939406 DOI: 10.3109/00365529409092490] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND The relationship between superficial findings and the inner structure of gastric ulcers is unclear. The present study was undertaken to clarify the relationship between them. METHODS In the first study, 43 patients with active gastric ulcers were examined by endoscopic ultrasonography (EUS) in each stage of Sakita's endoscopic classification. In the second study, 16 patients with gastric ulcer scars were examined by EUS in both S1 stage and S2 stage. RESULTS Ulcer area, ulcer length, thickness of the ulcer base, and diameter of the crater differed significantly in each endoscopic stage. Ulcer area, ulcer length, and thickness of the ulcer base differed significantly even between S1 stage and S2 stage. Mean ulcer area in S1 stage was 96.9 mm2; this shows that the ulcer scar in S1 stage is incomplete with regard to tissue contraction. Although ulcer area in S2 stage had shrunk significantly compared with that in S1 stage, it still remained 53.3 mm2. This implies that the risk of local recurrence remains even in S2 stage. CONCLUSIONS Sequential observation by EUS showed that the healing of the ulcer surface strongly reflected the healing within the ulcers.
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Funaki T, Onodera H, Ushiyama N, Tsukamoto Y, Tagami C, Fukazawa H, Kuruma I. The disposition of the tolcapone 3-O-methylated metabolite is affected by the route of administration in rats. J Pharm Pharmacol 1994; 46:571-4. [PMID: 7996385 DOI: 10.1111/j.2042-7158.1994.tb03859.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Catechol-O-methyltransferase (COMT) catalyses the transfer of the methyl group from S-adenyl-L-methionine (SAM) to one of the hydroxy groups of a catechol, usually the hydroxy group in position 3. COMT is present mainly in a soluble form (S-COMT) in the cytosol, but a small fraction is bound to cell membranes (MB-COMT). MB-COMT has higher affinity for the catechol substrate than does S-COMT by a factor of > 10, and high MB-COMT activity is observed in the intestinal muscle layer. The present study investigates the effect of the administration route on the disposition of the tolcapone 3-O-methylated metabolite following intravenous and oral tolcapone administration in rats. Tolcapone is a substrate for COMT although the 3-O-methylated metabolite produced has no pharmacological actions. The 3-O-methylated metabolite was eliminated very slowly following oral administration of tolcapone, and its concentration approached a plateau level, which was in contrast to the situation following intravenous administration of tolcapone. It is thought that the oral dose of tolcapone receives a high exposure to MB-COMT in the intestinal muscle layer during its absorption, and tolcapone seems to form a complex with MB-COMT having a high affinity constant (i.e. a very low Ki). The fraction of the intravenous dose of tolcapone metabolized to the 3-O-methylated metabolite at 10 mg kg-1 was 2.6%, whereas those of the oral doses, which were corrected by the bioavailability, were 5.4% for 20 mg kg-1 and 2.7% for 40 mg kg-1.
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Abstract
BACKGROUND Although primary gastric lymphoma is the most common extranodal lymphoma, no specific staging system exists. METHODS The authors reviewed 98 cases histologically classified according to the Working Formulation, including low grade B-cell lymphoma of mucosa-associated lymphoid tissue type. Survival rates were calculated by the Kaplan-Meier method according to T, N, and M of the general rules of the International Union Against Cancer TNM system. The definitions of these categories are as follows: T1, tumor invades the lamina propria or submucosa; T2, the muscularis propria; T3, the subserosa; T4, the serosa without invasion of adjacent structures; T5, adjacent structures; N0, no regional lymph node metastasis; N1, perigastric lymph nodes within 3 cm of the edge of the primary tumor; N2, perigastric lymph nodes more than 3 cm from the edge of the primary tumor or in lymph nodes along the left gastric, common hepatic, splenic, or celiac arteries; N3, paraaortic and hepatoduodenal lymph nodes and/or other intraabdominal lymph nodes; N4, beyond N3; M0, no distant metastasis; and M1, positive. RESULTS The overall 5-year survival rate was 83.5%; it was 100% in T1, 82.4% in T2, 84.2% in T3, 52.9% in T4, and 33.3% in T5; 93.9% in N0, 90.5% in N1, 66.2% in N2, and 44.4% in N3/N4; and 86.0% in M0 and 25.0% in M1. Based on these results, the authors proposed a new staging system as follows: Stage I, T1/N0, N1/M0; Stage II, T1/N2/M0, T2,T3/N0,N1,N2/M0; Stage III, T4,T5/any N/M0, any T/N3, N4/M0; and Stage IV, any T/any N/M1. According to this system, the 5-year survival rate significantly decreased as the stage progressed: 100% in Stage I, 88.9% in Stage II, 52.1% in Stage III, and 25.0% in Stage IV. In Stages I and II, survival rates were not significantly different whether chemotherapy was done or not, whereas in Stage III all patients treated with surgery alone died. CONCLUSIONS This staging system is useful for assessing prognosis of and deciding a therapeutic plan for primary gastric lymphoma.
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Abstract
BACKGROUND Although primary gastric lymphoma is the most common extranodal lymphoma, no specific staging system exists. METHODS The authors reviewed 98 cases histologically classified according to the Working Formulation, including low grade B-cell lymphoma of mucosa-associated lymphoid tissue type. Survival rates were calculated by the Kaplan-Meier method according to T, N, and M of the general rules of the International Union Against Cancer TNM system. The definitions of these categories are as follows: T1, tumor invades the lamina propria or submucosa; T2, the muscularis propria; T3, the subserosa; T4, the serosa without invasion of adjacent structures; T5, adjacent structures; N0, no regional lymph node metastasis; N1, perigastric lymph nodes within 3 cm of the edge of the primary tumor; N2, perigastric lymph nodes more than 3 cm from the edge of the primary tumor or in lymph nodes along the left gastric, common hepatic, splenic, or celiac arteries; N3, paraaortic and hepatoduodenal lymph nodes and/or other intraabdominal lymph nodes; N4, beyond N3; M0, no distant metastasis; and M1, positive. RESULTS The overall 5-year survival rate was 83.5%; it was 100% in T1, 82.4% in T2, 84.2% in T3, 52.9% in T4, and 33.3% in T5; 93.9% in N0, 90.5% in N1, 66.2% in N2, and 44.4% in N3/N4; and 86.0% in M0 and 25.0% in M1. Based on these results, the authors proposed a new staging system as follows: Stage I, T1/N0, N1/M0; Stage II, T1/N2/M0, T2,T3/N0,N1,N2/M0; Stage III, T4,T5/any N/M0, any T/N3, N4/M0; and Stage IV, any T/any N/M1. According to this system, the 5-year survival rate significantly decreased as the stage progressed: 100% in Stage I, 88.9% in Stage II, 52.1% in Stage III, and 25.0% in Stage IV. In Stages I and II, survival rates were not significantly different whether chemotherapy was done or not, whereas in Stage III all patients treated with surgery alone died. CONCLUSIONS This staging system is useful for assessing prognosis of and deciding a therapeutic plan for primary gastric lymphoma.
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Yoshikane H, Tsukamoto Y, Niwa Y, Goto H, Hase S, Shimodaira M, Maruta S, Miyata A, Yoshida M. Superficial esophageal carcinoma: evaluation by endoscopic ultrasonography. Am J Gastroenterol 1994; 89:702-7. [PMID: 8172141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES The aim of this study was to evaluate the usefulness of endoscopic ultrasonography (EUS) in the staging of superficial esophageal carcinoma (SEC). METHODS We examined the histopathologic findings of 28 patients with SEC which was confirmed in the postoperative histologic evaluation. The EUS results preoperatively estimated were compared with them. RESULTS There were nine patients with mucosal carcinoma (two intraepithelial carcinomas and seven carcinomas limited to the mucosal layer) and 19 patients with submucosal carcinoma. The mucosal carcinomas revealed no lymph node metastasis or vessel permeation, whereas the submucosal carcinomas revealed lymph node metastasis (71%) and vessel permeation (lymphatic, 58%, vascular, 21%). The accuracy rates of depth of invasion by EUS were mucosa, 67% (6/9); submucosa, 79% (15/19); and total, 75% (21/28). EUS could not detect microinvasion to the submucosa. The overall accuracy rate of EUS in the evaluation of periesophagogastric lymph node metastasis was 72%: sensitivity 58% and specificity 85%. CONCLUSIONS It has been clinically proved important to differentiate mucosal carcinoma from submucosal carcinoma in the staging of SEC, and EUS is recommended in differentiating between them.
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