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Biomedical subjects

K Katoh

Publications and source records attributed to K Katoh.

At least 217 records · Page 12Linked to original sources
PubMed1989

[Increased plasma and urinary Na+-K+ ATPase inhibitory activity and elevated blood pressure in metoclopramide-treated rats].

Our recent studies demonstrated that dopaminergic receptor may play an important role in controlling blood pressure and renal sodium handling. This study was designed to investigate whether endogenous Na+-K+ ATPase inhibitors are related to changes in blood pressure and sodium balance, caused by the administration of metoclopramide (MC), a dopamine (D2) receptor antagonist, and sodium loading. Young male Wistar rats (250 approximately 300 g) were raised under three different conditions, control (control group), 1% NaCl loading (NaCl group) and 1% NaCl plus 1.5 mg/kg/day of metoclopramide (MC group) for 7 days. Systolic blood pressure (SBP), urinary and plasma Na+-K+ ATPase inhibitory activity (ATPI), urinary sodium, potassium and catecholamine excretions were measured. SBP in the MC group elevated from 116 +/- 2 mmHg to 134 +/- 4 mmHg, but there were no changes in SBP in the control and NaCl groups. Urine volume and urinary sodium excretion significantly increased in not only the NaCl group but also in the MC group. Plasma ATPI in both the NaCl and MC groups was higher than in the control group (p less than 0.001), and the level of ATPI in the MC group was significantly higher than in the NaCl group (p less than 0.05). Urinary ATPI in the control group was not detected after 7 days, but that in the NaCl and MC groups was clearly increased. The excretions of urinary catecholamines remained unchanged in all groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Effects of butyric acid and analogues on amylase release from pancreatic segments of sheep and goats.

The specificity of the structural elements of a short-chain fatty acid for stimulating amylase release was investigated in superfused pancreatic segments of sheep and goats in vitro using butyric acid and analogues. Monocarboxylic (cyclohexanecarboxylic and benzoic) acids were as effective as butyric acid, whilst 4-phenyl-n-butyric and dicarboxylic (succinic and phthalic) acids were weak stimulants. The amylase release evoked by butyric acid was markedly reduced in the presence of these compounds. Replacement of hydrogens by a hydroxyl group or amino group or reduction of the carboxyl group to alcohol diminished, while replacement of hydrogen by chloride at the 3 carbon position did not change, the ability to stimulate amylase release. The dose-response curve for butyric acid was shifted to the right in parallel in the solution containing succinic acid at 8 x 10(-4) mol/l. The maximal increment (but not ED50) of amylase release evoked by ACh was severely reduced in the solution simultaneously containing butyric acid at 10(-3) mol/l. These results suggest that short-chain fatty acids are required to possess both carboxyl (hydrophilic) group and hydrophobic tails in order to have the ability to stimulate amylase release, and that amylase release evoked by butyrate is caused through specific recognizing sites for short-chain fatty acids which might be different from ACh receptors, in the pancreatic segments of sheep and goats.

Acetylcholine↗
PubMed1989

Effect of 15(R)-15-methyl PGE2 (arbaprostil) on duodenal bicarbonate secretion in rat.

The present study was designed to observe the effect of 15(R)-15-methyl PGE2 (arbaprostil) on duodenal bicarbonate secretion in male Wistar rats anesthetized with urethane. A proximal duodenal loop (1.5cm) was made and perfused with saline (pH4.5) in an air tight circle system. The pH and Pco2 of the perfusing fluid were measured continuously and the quantity of bicarbonate was calculated according to the Henderson-Hasselbalch equation. Vehicle or arbaprostil was injected intravenously as a bolus injection. The total output of bicarbonate in 30 min was as follows; control: 0.449 +/- 0.093 microEq (mean +/- SE); 1,10 and 100 mu/kg of arbaprostil: 0.752 +/- 0.218, 2.75 +/- 0.430 and 5.958 +/- 0.578 microEq respectively. Arbaprostil (10 and 100 micrograms/kg) increased the total output of bicarbonate significantly (p less than 0.001). The rate of secretion was also increased by arbaprostil.

Animals↗
PubMed1989

Insulin-like growth factor-I, GH, insulin and glucagon concentrations in bovine colostrum and in plasma of dairy cows and neonatal calves around parturition.

1. The IGF-I concentrations in colostrum on days 1 and 2 after parturition were higher than those in cow and neonate plasma. 2. The modest increase in GH concentrations in cow plasma around parturition would not be enough to stimulate IGF-I release by tissues. 3. The concentrations of insulin, GH and glucagon in colostrum were substantially lower than those in plasma.

Animals↗
PubMed1989

Delayed neurotoxicity and toxicokinetics of leptophos in hens given repeatedly by low-dose intravenous injections.

The repeated intravenous injections (RIVInj) of 5 mg/kg/day leptophos [O-(4-bromo-2, 5-dichlorophenyl) O-methyl phenylphosphonothioate] for 3 consecutive days caused delayed ataxia in 4 out of 9 hens (44.4%). And one out of 9 hens (11.1%) given RIVInj of 3 mg/kg leptophos for 5 days was affected with ataxia. Twenty hens, however, which received a single intravenous injection (SIVInj) of 15 mg/kg leptophos did not exhibit any delayed neuropathic signs at all. Thus, delayed neurotoxicity was increased by the subdividing RIVInj of the critical dose which was shown in the SIVInj of leptophos. The leptophos concentration in plasma and liver decreased very rapidly after finish of either SIVInj or RIVInj. Although no significant differences were observed in the biological half life of leptophos in plasma by different dosages, the mean level of leptophos decreased significantly with frequency of injections. On the contrary, the evident accumulation of leptophos was observed in only sciatic nerve with RIVInj. Leg muscle maintained relatively high level of leptophos after the last injection. These results suggest that leptophos seems to transfer from blood to affinitive tissues such as sciatic nerve or leg muscles and to accumulate there easily in initial stage after repeated iv injections, and that this causes the enhancement of neuropathy with repeated administrations of divided critical dose of leptophos in both iv and oral administration.

Animals↗
PubMed1989

Biological significance of phospholipids in the rat stomach--from the viewpoint of electron microscopy.

The structures of gastric phospholipids (PLs) were further confirmed by employing an improved fixative and fixation method. PLs were detected on the free surface of superficial mucous epithelial cells and epithelial cells of the foveolar crypts. PLs were also detected inside superficial mucous cells and epithelial cells of the foveolar crypts. The gastric PLs were secreted through a merocrine-like mechanism. Apocrine-like secretion of PLs was also observed in some electron microscopic images. PLs were observed in the intercellular and intracellular secretory canaliculi of parietal cells and also in the rest of the parietal cytoplasm. The above findings indicated the localization of PLs on the surface of the gastric lumen and in the gastric mucosa, and suggested that, similar to gastric glycoproteins, gastric PLs play an important role in the gastric mucous barrier and mucosal barrier.

Animals↗
PubMed1989

[Reverse redistribution in the stress thallium scan--correlation of coronary blood flow and myocardial damage].

In order to make clear 'reverse redistribution (RR)' phenomenon in stress thallium scan we investigated 477 consecutive patients who were consisted of 74 cases with PTCA (PTCA group), 86 cases with coronary artery bypass graft (CABG group) and 317 cases without any revascularization (N group). RR was detected in 12 cases out of PTCA group (16%), in 11 cases out of CABG group (13%) and in 10 cases out of N group (3.2%), and the incidence of RR in PTCA or CABG group was higher than that of N group (p less than 0.01). In 33 patients with RR the cases without significant coronary artery stenosis were more than those with stenosis (p less than 0.01) and the cases with myocardial damage were more than those without damage (p less than 0.01). In quantitative analysis washout rate at the RR areas showed relatively high value, but it was not significant compared with normal value (53 +/- 9.0% vs. 49 +/- 1.9%). In conclusion, RR had a tendency to appear in the condition of normal myocardium mingled with scar and of sufficient coronary blood flow. The mechanism of the phenomenon was thought to be that initial uptake of thallium in the partially scarred area was as high as in the normal myocardium, but washout of thallium from its remaining normal myocardium is normal or faster so that the defect appears at the myocardium mingled with scar. Therefore existence of reverse redistribution suspects the myocardium mingled with scar and sufficient coronary blood flow to the remaining normal myocardium.

Adult↗
PubMed1989

[Effect of activation of the reticuloendothelial system on hepatocyte regeneration in partially hepatectomized rats].

Enhanced effect on rat hepatocyte regeneration through activation of the reticuloendothelial system (RES) was investigated. RES was activated using by OK-432 and the phagocytic activity (K-value) increased 2-fold over control rats 24 hours after intraperitoneal injection of OK-432. In OK-432 treated rats, the amount of cyclic AMP in the regenerating liver also increased 1.5-fold higher than in control rats 14 hours after hepatectomy. After 70% partial hepatectomy, liver DNA synthesis in OK-432 treated rats increased 2 to 5-fold higher than in control rats. There was a good correlation between the K-value before hepatectomy and DNA synthesis 24 hours after hepatectomy (r = 0.96). Therefore the RES is one of the most important regulatory factors in liver regeneration. Augmentation of RES before hepatectomy may prevent hepatic failure after resection in liver diseases.

Animals↗
PubMed1989

A cluster of human T-lymphotropic virus type-I carriers found in the southern district of Tokushima Prefecture.

Since we had experience of eight patients with adult T-cell leukemia lymphoma from 130 cases of non-Hodgkin's lymphoma between 1978 and 1986, a sero-epidemiological survey of anti human lymphotropic virus type-I (HTLV-I) antibody was performed using a gelatin particle agglutination test, an enzyme-linked immunosorbent assay and an indirect immunofluorescence assay for 2,190 adults (768 men and 1,422 women) aged between 21 and 86 years, in the southern district of Tokushima Prefecture. The inconclusive data obtained using the above mentioned methods have been re-examined by western blotting analysis using enzyme-labelled anti IgM and anti IgG. There was an overall prevalence rate of 6.0% (132/2, 190) but higher rate were found in village C (10.9%) and village D (14.2%). These two villages together with town K (6.1% seropositive) form one community unit with a small population in a mountain area, which could be prone to producing a cluster of HTLV-I carriers. Town G with 8.0% sero-positivity is on the Pacific Ocean coast neighboring one of the endemic areas in the eastern section of Kohchi Prefecture. Interestingly, only IgM antibody was detected in 17 of 137 carriers (13%), all females who had never had a blood transfusion, suggesting them to h ave been in a sort of immunodeficient state, as reported in cases of HTLV-I infection. In 13 of 29 HTLV-I carriers (44.8%) from villages C and D, the viral antigen was detected in 1-9% (0.41 +/- 0.19%) of the peripheral blood mononuclear cells after being cultured with phytohemagglutinin for three days. The data indicate that those carriers had evidently been infected with the HTLV-I virus.

Adult↗
PubMed1989

[Analysis of factors influencing the accuracy of ejection fraction measurement based on the thermal washout technic--investigation in a model heart].

Evaluation of ejection fraction and ventricular volume is more difficult in the right side of the heart than in the left side. Thermal washout method in the right ventricle with the aid of a rapid response thermistor made it possible in the clinical practice, but its accuracy is uncertain. We attempted to elucidate what factors could influence the accuracy of the measurement of the right ventricular ejection fractions in a model circuit and artificial heart equipped with two one-way valves. Findings are as follow: 1) By ventricular injection of the cold water it is possible to evaluate the ejection fractions more accurately than by atrial injection. The latter technique measured the ejection fraction 8.4% lower than the actual values. 2) The first ejection fraction measured will be the most accurate among the serially obtained ejection fractions using a thermal washout curve. 3) When the ejection fraction is high, the ejection fractions calculated from the later part of a thermal washout curve will be falsely low. 4) When the cold water is injected through the catheter running in the circuit, the effect of the catheter cooling could not be neglected and ejection fraction will be measured falsely low. The temperature change is so small in the later part of the descending limb of the thermal washout curve, that the effect of catheter cooling and ventricular cooling will be exaggerated and the calculation of the temperature change will be measured falsely high. This seems to be the cause of our findings in this research.(ABSTRACT TRUNCATED AT 250 WORDS)

Hot Temperature↗
PubMed1989

[An autopsied case of malignant lymphoma of the pancreas with an elevation of the serum Ca 19-9 level].

A 37-year-old male was admitted to hospital because of a right hypochondrial pain and icterus. His physical examination showed hepatosplenomegaly, and the laboratory findings demonstrated abnormal hepatic and pancreatic functions. A CT examination revealed a large mass of a low density in the pancreas head and tail. Further, an immunological study revealed that the patients serum Ca 19-9 level was elevated, but that the CEA and AFP levels were normal. Both the pathological and cytological examinations, however, did not indicate a malignancy of the pancreas. The patient subsequently developed uremia, a hemorrhagic tendency, and then died. An autopsy confirmed a pancreatic tumor which occupied the head of pancreas. Histologically, the tumor contained round cells with scanty cytoplasms and showed a sarcomatous pattern. An immunohistochemical study showed that the LCA, MB-1, and the LN-1 for B cell markers were positive, while the MT-1 for T cells was negative. The case illustrates a malignant lymphoma of the pancreas which demonstrated a serum Ca 19-9 elevation.

Adult↗
PubMed1989

Simple enzymatic method for determining 1,5-anhydro-D-glucitol in plasma for diagnosis of diabetes mellitus.

We have developed a simple method for determination of 1,5-anhydro-D-glucitol in plasma, based on use of pyranose oxidase (EC 1.1.3.10), an enzyme with specificity toward pyranoid compounds such as 1,5-anhydro-D-glucitol and glucose. Plasma samples deproteinized with trichloroacetic acid are passed through a two-layer mini-column packed with strongly basic anion (OH- form, the upper layer) and strongly acidic cation (H+ form, the lower layer) exchange resins. 1,5-Anhydro-D-glucitol is efficiently recovered in the flow-through fraction, which is almost devoid of other sugars that are sensitive to pyranose oxidase. The hydrogen peroxide formed in the enzymatic oxidation of 1,5-anhydro-D-glucitol is detected by a standard method utilizing an enzymatic color-developing system. The overall assay system is highly specific for 1,5-anhydro-D-glucitol. The correlation between results obtained in the present method (x) and in the gas-liquid chromatographic (GLC) method (y) was: y = 1.062x-0.293 mg/L (r = 0.997, n = 49, Sxy = 10.78 mg/L). Compared with GLC, our method is simpler in the sample treatment step and quicker in the measuring step. The precisions of the two methods are comparable.

Benzothiazoles↗
PubMed1989

[Development of a new quantitative analysis for thallium myocardial SPECT images--quantitative STEREO-VIEW method and evaluation of its clinical usefulness].

We have developed a three-dimensional quantitative display method, Quantitative STEREO-VIEW method (STEREO-VIEW method), for analysis of thallium (Tl) myocardial SPECT images and have evaluated its clinical usefulness. SPECT data were obtained immediately and 4 hours after the exercise, and contour lines for outer edges of left ventricular (LV) myocardium were detected from 10 slices of short axial images in delayed scan. LV wall was divided into 510 segments by dividing each slice into 51 sectors and LV myocardium was three-dimensionally reconstructed. Mean Tl counts, %T1 uptake and washout rate (WR) of each segment were calculated and these values were represented such as infarcted area display, redistribution display and WR display on STEREO-VIEW. Furthermore, extent index (EI), severity index (SI) and intensity index (II) were defined to express the degree of perfusion abnormality using WR value of each segment. In the 25 patients with coronary revascularization, improving rate of these indices correlated well with that of double product significantly. STEREO-VIEW method resembled in the original shape of left ventricle of each patient, so STEREO-VIEW method has made it easier to discriminate the accurate extent of ischemic lesion. In addition, EI, SI and II using WR were good indices for coronary perfusion and these were thought to be useful on clinical study.

Aged↗