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Biomedical subjects

M Katoh

Publications and source records attributed to M Katoh.

At least 253 records · Page 14Linked to original sources
PubMed1993

Negative feedback regulation of acid secretion: linkage of acid secretion and mucosal defense.

To regulate inappropriate or excessive acid secretion that may be harmful not only to surrounding mucosal cells but also parietal cells themselves, versatile mechanisms operate to control acid secretion. In this article elaborate mechanisms that participate in the control of acid secretion are described with our data and a review of relevant findings in the literature concerning the action or secretion of key regulatory molecules. The analysis of the regulatory mechanisms revealed that appropriate secretory control can be achieved by multiple feedback regulations, which are closely coordinated with mucosal defense. In the feedback circuits, the regulatory factors cannot be simply categorized into either aggressive or defensive factors. Therefore we propose that the mucosal integrity and tissue homeostasis would be better understood by a feedback loop model rather than by a dualistic balance model.

Animals↗
PubMed1993

Helicobacter pylori may be transmitted through gastrofiberscope even after manual Hyamine washing.

Endoscopy is an effective diagnostic technique for gastric cancer, which is believed to be associated with Helicobacter pylori. Manual Hyamine washing is a widely used fiberscope cleaning method. Urease B gene of Helicobacter pylori was detected in 50% of the wash-out samples from the biopsy-suction channel of a fiberscope after manual Hyamine washing by nested polymerase chain reaction, and bacterial culture revealed viable Helicobacter pylori in 19%. However, Helicobacter pylori was not detected by either of the above methods in the biopsy-suction channel of the fiberscope after mechanical washing. These findings indicate that manual Hyamine washing of fiberscopes is insufficient to prevent iatrogenic Helicobacter pylori transmission, and that mechanical washing after manual Hyamine washing is essential.

Base Sequence↗
PubMed1993

Changes of sagittal-plane ankle motion and ground reaction force (fore-aft shear) in normal children aged four to 10 years.

The authors investigated the changes in ankle-joint kinematics and ground reaction force during gait in normal children aged four to 10 years. Dorsiflexion of the ankle joint became slower and well controlled from early to mid stance phase with age. The main changes were found at about five years of age. The peak for the fore-aft shear component of the ground reaction force in the deceleration phase occurred later, and was noted during dorsiflexion. However, the peak for plantar flexion, plantar flexion angular velocity and the fore-aft shear component of ground reaction force (all seen during the acceleration phase) did not change significantly with age. These findings appear to be related to maturation of the ankle plantar flexors.

Age Factors↗
PubMed1993

Thrombolysis with intracoronary administration of YM866, a novel modified tissue-type plasminogen activator, in a canine model of coronary artery thrombosis.

We compared the thrombolytic activity of YM866, a novel modified tissue-type plasminogen activator, with that of t-PA by intracoronary administration in a canine thrombosis model of copper coil-induced 6-hr-old thrombi. Either drug was administered by a single injection (10 min) or multiple injection (4 x 10 min) under heparinization (300 IU/kg, i.v.). The reperfusion rate of YM866 was 4 times higher than that of t-PA when administered by single injection. Time to reperfusion of YM866 by single injection was shorter than that of either agent by multiple injection. No group showed any decrease in plasma fibrinogen levels. No acute reocclusion was seen in animals with YM866 by single injection. The improved thrombolytic activity of YM866 by single injection correlated with the relatively higher antigen levels of this agent due to its prolonged biological half-life. These results suggest that single intracoronary administration of YM866 is a safe and effective thrombolytic method for rapid recanalization and lowered acute reocclusion without activation of systemic fibrinolysis.

Animals↗
PubMed1993

Thrombolytic activity of a novel modified tissue-type plasminogen activator, YM866, in a canine model of coronary artery thrombosis.

The thrombolytic activity of a novel modified t-PA, YM866, was compared with that of a recombinant t-PA in a canine model of copper coil-induced coronary thrombosis. The coronary thrombus was allowed to age for 1, 3 or 6 hr before either drug was administered. YM866 was administered by i.v. bolus injection, while t-PA was given by the same method, as well as by 60-min i.v. infusion. YM866 showed thrombolytic activity 2 to 4 times as potent as that of t-PA when administered by bolus injection, the difference in thrombolytic effect being obvious in the 3- and 6-hr-old thrombi. Coronary reperfusion was achieved more rapidly with YM866 than with i.v. infusion of t-PA. In animals injected with doses of more than 0.1 mg/kg of YM866, no acute reocclusion occurred. Depletion of plasma fibrinogen to 70% of baseline levels was observed in animals given 0.2 mg/kg YM866, 0.4 mg/kg t-PA by bolus, and 0.6 mg/kg t-PA via infusion. The residual plasma YM866 and t-PA antigen 30 min after bolus injection was 25% and 3% of the peak levels, respectively. YM866, administered by i.v. bolus injection, was thus confirmed to exert a thrombolytic effect superior to that of bolus injection and infusion of t-PA, without systemic fibrinolytic activation. These results suggest the potential clinical applicability of YM866 as a thrombolytic agent that can be administered by i.v. bolus injection for acute myocardial infarction.

Amino Acid Sequence↗
PubMed1993

Historical control data of organ weight and gross findings in F344/DuCrj rats and B6C3F1 mice.

Organ weight and gross postmortem findings of control Fischer 344/DuCrj rats and B6C3F1 mice are presented from subchronic, chronic toxicity and carcinogenicity studies that were conducted over a 9 year period at our center (An-Pyo Center). The mean organ weight of the liver, kidney, spleen and the lung were increased associated with age in both species. The most common findings observed at 109 weeks in both species were thymic atrophy, enlargement of the spleen, dilation of the lumen of the uterus and ovarian cysts. Male and female Fischer 344/DuCrj rats commonly exhibited a granular surface of the kidneys, hypertrophy of and/or nodular pituitary glands and subcutaneous tissue masses. Multiple white patches and hypertrophy or atrophy of the testes, atrophy of the seminal vesicles and prostate and nodules in the pancreas were seen frequently in male rats. Malformative nodule in the liver was a common finding in female rats. The most common lesions seen in both male and female B6C3F1 mice were nodules in the liver and lungs and enlargement of the lymph nodes. Nodules on the preputial gland were commonly seen in the males. Sex differences were evident in the incidence of some of the above findings. These historical data will contribute to analyze the organ weight and gross findings at necropsy in long-term toxicity and carcinogenicity studies.

Animals↗
PubMed1993

[Neutrophil functions during treatment with granulocyte colony-stimulating factor (G-CSF) in the elderly with non-Hodgkin's lymphoma: including two patients accompanied with interstitial pneumonitis during the treatment with G-CSF].

We examined neutrophil functions in seven elderly patients with non-Hodgkin's lymphoma before and during treatment with granulocyte colony-stimulating factor (G-CSF) at the neutropenic stage after combination chemotherapy. Subcutaneous injection of 75 micrograms/d of G-CSF produced by E. coli was started when the neutrophil count decreased less than 1,500/microliter, and continued until the neutrophil count increased to about 10,000/microliter. The phagocytic activity of neutrophils from the elderly on day 3 of G-CSF treatment was markedly enhanced; 1,129.9 +/- 403 ps/100 PMNs, which was 185.7 +/- 31.4% (p < 0.001) as compared with that before G-CSF treatment. The neutrophil alkaline phosphatase (NAP) activity was also enhanced on day 3; 398.3 +/- 48 score, which was 135.2 +/- 5.1% (p < 0.001) as compared with that before G-CSF treatment. Two patients developed interstitial pneumonitis during or shortly after the treatment with G-CSF. Interstitial pneumonitis suddenly developed when their neutrophil count was increased, and the phagocytic activity and NAP activity recovered. The phagocytic activity of neutrophils from them was enhanced to 1,090 +/- 26 ps/100 PMNs and 772 ps/100 PMNs during the treatment with G-CSF, as compared with that before G-CSF treatment of 644 +/- 29 ps/100 PMNs and 465 +/- 69 ps/100 PMNs, respectively. The NAP activity was also enhanced to 372 from 264. One patient suffered from transient pulmonary dysfunction during the treatment with G-CSF. His neutrophil count was more than 13,000/microliter, and the phagocytic activity enhanced to 949 +/- 105 ps/100 PMNs. Dyspnea with suppressed PaO2 recovered reversibly after cessation of G-CSF.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1993

[Dose escalation study of high dose etoposide in autologous hematopoietic stem cell transplantation].

Eight cases with poor prognosis hematological malignancies (non-Hodgkin lymphoma, 6 cases; acute non-lymphocytic leukemia, 2 cases) and nine cases with non-hematological malignancies were treated with high dose etoposide (VP16) containing regimen followed by autologous hemopoietic stem cell transplantation. Results were as follows; 1) all of three chemotherapy sensitive relapse patients with hematological malignancies continue complete remission without any cyto-reductive therapy 2) one of four refractory relapse patients continue remission 3) partial anti-tumor effect was noted in non-hematological malignancies, however, only two cases continue complete remission. Remission duration of other responders was not so long. The results disclosed the dose-limiting factor of high-dose VP16 therapy as reversible stomatitis with no related mortality, and maximal tolerated dose appears to be 60 mg/kg over 72 hr with 45 mg/kg as a safe and recommended therapeutic dose in future clinical trial. The clinical effect of dose escalation was not clearly demonstrated.

Adult↗
PubMed1993

[Effect of training fitness on obesity, hypertension, hyperlipidemia and disorders in glucose metabolism].

Effects of physical training on obesity, hypertension, hyperlipidemia and disorders of glucose metabolism were investigated in 359 males, 30-59 years of age. Body mass index (BMI), systolic and diastolic blood pressure (SBP and DBP), high density lipoprotein cholesterol (HDL-C), total cholesterol (TC) and fructosamine (FA) were measured before and after the 2 month period of physical training at intensities of about 50% of maximal O2 uptake. Results are summarized as follows; 1. Means of BMI, SBP, DBP, TC and FA after the training were significantly lower than before the training. Mean of HDL-C was significantly higher than before the training. 2. In subjects with high BMI (n = 124), high SBP (n = 129) and high DBP (n = 128), means of BMI, SBP and DBP decreased with increase of training time per week. In subjects with low HDL-C (n = 104), high TC (n = 135) and high FA (n = 66), changes in means of TC, HDL-C and FA after the training did not show a relationship to training time per week. 3. Differences observed for measured values before and after the training of 2-3 hours per week were 0.4 kg/m2 in BMI, 15 mmHg in SBP and 10 mmHg in DBP, suggesting that training of 2-3 hours per week was effective in intervention of obesity and hypertension.

Adult↗
PubMed1993

[A new application of immunoconjugate to reduce the local recurrence of colorectal cancer].

To examine whether or not immunoconjugate-A7-NCS can contribute for the reduction of local recurrence of colorectal cancer, the present study was undertaken. The study included examination of local retension, lymphatic delivery and inhibitory effect on tumor development after local administration of A7-NCS. The result showed that locally injected A7-NCS showed a high local retension, a high regional lymph node accumulation and a high inhibitory effect on tumor development. This finding indicates that A7-NCS can be a new promising tool for reducing the local recurrence of colorectal cancer.

Animals↗
PubMed1993

[Helicobacter pylori infection in gastric cancer].

The relationship between Helicobacter pylori (H. pylori) infection and gastric cancer becomes the topics in the world, since some reports thereon in 1991. The purpose of this study was to know the prevalence of H. pylori infection in many patients with gastric cancer. We examined the H. pylori IgG antibody in 507 patients with gastric cancer resected surgically in our hospital from 1989 to 1991, retrospectively. For the test of H. pylori IgG antibody, HM-CAP EIA kit (Italy, ENTERIC PRODUCTS Co.) was used. The overall detection rate of H. pylori IgG antibody was 75% (378/507). H. pylori infection was significant significantly frequent in early cancer (80%, 231/288) than advanced cancer (67%, 147/219). But, the other clinicopathological features such as sex, age, histological type, location and the degree of intestinal metaplasia were not significantly correlated with H. pylori infection. To evaluate the risk of H. pylori infection for gastric cancer, we are going to plan a matched-pair case-control study.

Aged↗
PubMed1993

Our technique of parathyroid autotransplantation in operation for papillary thyroid carcinoma.

BACKGROUND: For papillary thyroid carcinoma, we have used our standard operative method consisting of total thyroidectomy, bilateral lymph node dissection, and parathyroid autotransplantation. Our special parathyroid transplantation method involves transplantation of the minced glands into the pectoralis major muscle. We investigated whether this method is useful for preserving parathyroid function. METHODS: In 17 patients who underwent our standard operation for papillary thyroid carcinoma, the intact parathyroid hormone (PTH) and serum calcium levels were determined for 4 weeks after the operation. RESULTS: In all cases the intact PTH levels fell below detectable limits immediately after operation and then recovered to the preoperative level about 2 weeks after the operation. The same recovery patterns were observed in two groups undergoing transplantation of two glands and three or four glands. CONCLUSIONS: These recovery patterns of intact PTH levels seem to indicate that the glands were grafted successfully and recovered their function. Our method is thought to be useful for preserving parathyroid function after surgery.

Calcium↗
PubMed1993

[A case of two-chambered right ventricle associated with severe pulmonary valve regurgitation].

A 40-year-old female was admitted to the hospital with the chief complaints of dyspnea on effort. Echocardiography and cardiac catheterization revealed an abnormal muscle bundle in the right ventricle which divided right ventricle into two chambers with the pressure gradient of 86 mmHg between them. And severe regurgitation associated with hypoplastic pulmonary valve and ventricular septal defect were noted. We removed the abnormal muscle bundle through the right atrial and ventricular approach, and pulmonary valve replacement and VSD closure were carried out. We report a case of two-chambered right ventricle with severe pulmonary valve regurgitation because of its rarity.

Adult↗