Biomedical subjects

S Okada

Publications and source records attributed to S Okada.

At least 847 records · Page 47Linked to original sources

PubMed1992

Mifepristone (RU 486), a blocker of type II glucocorticoid and progestin receptors, reverses a dietary form of obesity.

The effect of mifepristone (RU 486), a blocker of type II glucocorticoid receptors on the development of obesity that follows the feeding of a high-fat (HF) diet to Osborne-Mendel (OM) rats, has been investigated. OM rats fed a HF diet gained more weight and had larger retroperitoneal and parametrial fat pads than OM rats fed a high-carbohydrate low-fat (LF) diet. RU 486 (30 mg.kg-1.day-1) for 14 days completely reversed the body weight gain and the increase in fat pad size of OM rats fed a HF diet. RU 486 had no effect on body weight of OM rats fed a LF diet, but did reduce fat pad weights. The data suggest that type II glucocorticoid receptor activity modulates body fat deposition and is essential for the development of obesity, although a minor role for progestin receptor activity cannot be ruled out.

Animals↗

PubMed1992

Differential inhibition of fat intake in two strains of rat by the peptide enterostatin.

The effect of enterostatin, the amino-terminal pentapeptide of pancreatic procolipase, on food intake was investigated in two strains of rat, the dietary fat-sensitive Osborne-Mendel (OM) rat and the dietary fat-resistant S5B/Pl rat. After an overnight fast, enterostatin inhibited intake of high-fat (HF) but not low-fat (LF) diets in OM rats, but had no effect in S5B/Pl rats. When fed a macronutrient three-choice diet, OM rats selected fat preferentially, whereas S5B/Pl rats selected carbohydrate. Enterostatin specifically inhibited the intake of fat in OM rats but not S5B/Pl rats fed a three-choice macronutrient diet. The activity of pancreatic colipase was increased in S5B/Pl rats on both HF and LF diets compared with OM rats. Pancreatic colipase activities were negatively related to the voluntary intake of fat on three-choice macronutrient diets. The data support the hypothesis that enterostatin may control the intake of dietary fat.

Animals↗

PubMed1992

Influence of prostaglandin E1 on slight proteinuria in non-azotaemic diabetics.

In an investigation into the effect of prostaglandin E1 on proteinuria in nephrotic diabetic nephropathy, five patients were treated with 40 micrograms prostaglandin E1 administered intravenously over 2 h twice daily for 4 weeks. The following parameters were compared before and after treatment: protein excretion in urine; total serum protein concentration; serum albumin concentration; creatinine clearance; blood urea nitrogen; and serum creatinine content. A further five patients with nephropathy resulting from non-insulin-dependent diabetes mellitus were selected as controls. Analysis of the results using Student's t-test showed no significant change in any of the parameters before and after treatment.

Adult↗

PubMed1992

Does a dose of 40 micrograms/day prostaglandin E1 reduce creatinine clearance in a patient with diabetic nephropathy of the nephrotic type?

The case history of a woman, who at the age of 25 years on the birth of her second child was found to be diabetic, is reported. Over the subsequent 30 years the patient had been treated with insulin, the dose administered being monitored at regular intervals. At the age of 52 years, the patient was diagnosed as suffering from hypertension and diabetic nephropathy of the nephrotic type. The patient's condition gradually deteriorated and at 55 years of age 40 micrograms/day prostaglandin E1 was given intravenously for 84 days. Treatment resulted in a decline in urinary protein without a reduction in creatinine clearance. Renograms confirmed an improvement in the vascular and secretory phases of both kidneys.

Alprostadil↗

PubMed1992

The Rolandic mu rhythm: a clinical study of the atypical group.

We studied 241 patients whose electroencephalograms (EEGs) showed 7-13 Hz arch shaped wave patterns (mu rhythm) that are known to appear in the Rolandic area. The patients were then classified into two groups depending on the conditions of appearance of the mu rhythm. Group I (typical group) consisted of 171 cases. In this group, the presence of the wave patterns was not affected by the opening of the eyes, and it was blocked by spontaneous movements, or when sensorimotor stimulation was applied. The characteristic symptoms for this group were observed in patients diagnosed as having well-controlled epilepsy, psychiatric disorders, collagen diseases, etc. In Group I, the peak lay between the ages 6 through 15. Group II (atypical group) consisted of 70 cases. In contrast to Group I, the presence of the wave patterns in this group was reinforced by drowsiness, photic stimulation and hyperventilation. The characteristic symptoms for this group were observed in patients diagnosed as having intractable epilepsy or organic brain disorders. In Group II the peak lay between ages 11 through 15. However, in Group II the cases were almost equally distributed among the various age groups. Paroxysmal abnormal EEG patterns were found to be jointly present with more frequency in the Group II sample of epileptic patients than the Group I sample. Therefore, when the mu rhythm associated with conditions indicating Group II type patients is observed, care must be exercised in the observation of further progression of the illness, and in searching for the possibility of organic brain disorders.

Adolescent↗

PubMed1992

Frontal spindle activity that appears in conjunction with nontraumatic diffuse encephalopathy.

This peculiar 11-14 Hz spindle activity appears predominantly in the frontal area, and was observed in eight patients with impaired consciousness caused by nontraumatic diffuse encephalopathy. Characteristic of this frontal spindle activity is its transience and accordance with changes in the arousal level of the patient. When the degree of impaired consciousness in the patient was minimal and clinically not very apparent, this spindle activity appeared during light drowsiness. In lethargic patients, it was observed when the patient's level of consciousness rose (e.g. immediately after opening and closing the eyes). These frontal spindles disappeared at the onset of Stage 2 sleep, when normal physiologic spindle waves that are dominant in the vertex area appeared. A paroxysmal discharge was sometimes recorded in association with the frontal spindle activity and it disappeared at about the same time as these spindles. The prognosis was satisfactory for all patients in whom frontal spindle activity was observed; its correlation to spindle coma is also studied.

Adolescent↗

PubMed1992

A growth hormone (GH) analog can antagonize the ability of native GH to promote differentiation of 3T3-F442A preadipocytes and stimulate insulin-like and lipolytic activities in primary rat adipocytes.

The effect of amino acid substitutions introduced to the third alpha-helix in bovine GH (bGH) was investigated. A GH analog (bGH-M8), in which three amino acids were substituted to form an idealized amphiphilic alpha-helix, possessed the same specific binding affinity as wild-type bGH to cell membranes prepared from 3T3-F442A cells or rat adipocytes. However, bGH-M8 failed to stimulate preadipocyte differentiation, as measured by the level of glycerol-3-phosphate dehydrogenase activity. An equimolar concentration of bGH-M8 was inhibitory for this adipogenic effect caused by bGH at a concentration of 30 pM. bGH-M8 also failed to induce an insulin-like response and reduced lipolytic potency in rat primary adipocytes. A 10-fold excess of bGH-M8 abolished the effect of wild-type bGH in the insulin-like and lipolytic assays. Thus, bGH-M8 inhibited these actions of wild-type bGH and, therefore, appears to be a competitive antagonist. These results suggest that a major biologically active domain resides in the third alpha-helix of bGH, which is independent of amino acids important in the initial interaction of GH with its receptor.

3T3 Cells↗

PubMed1992

Long-term maintenance of multilineal hemopoiesis in collagen gel culture.

We examined the long-term maintenance of multilineal hemopoiesis in a collagen gel culture of mouse bone marrow cells. When cells were inoculated into the gel, stromal cells formed foci that were composed of sinusoidlike capillary structures, fibroblastic cells, adipocytes and macrophages. Many small hemopoietic foci similar to granulocyte-macrophage colonies (CFU-GM) appeared within a week and disappeared after two weeks. Several large hemopoietic foci appeared after two to three weeks of culture, without a second challenge of marrow cells. These large hemopoietic foci were composed mainly of myeloid cells. Megakaryocytes and mast cells were also observed. When erythropoietin (EPO) was added to the culture at the beginning, the erythroid focus appeared after 3 weeks and the number of megakaryocytes was greater than that in the culture without EPO. However, when EPO was added to the cultures after 6 or 12 weeks, erythroid cells appeared after 1 week and the number of megakaryocytes increased. This hemopoiesis lasted more than 6 months.

Animals↗

PubMed1992

A novel sulfatase from Pseudomonas testosteroni hydrolyzing lithocholic acid sulfate.

Pseudomonas testosteroni ATCC 11996 was found to produce a novel bile acid sulfate sulfatase that hydrolyzes the sulfate ester bond in lithocholic acid sulfate (LCA-S). The enzyme synthesis was induced by several kinds of bile acids including LCA-S. Mn2+ functioned as an essential component for the enzyme synthesis and SO4(2-) suppressed it. This sulfatase hydrolyzes LCA-S to isolithocholic acid and sulfuric acid with inversion of alpha- to beta-configuration of the hydroxyl group at the third position of lithocholic acid.

Chromatography, Gas↗

PubMed1992

The prevalence of types I and II feline coronavirus infections in cats.

The types of feline coronaviruses that are prevalent throughout Japan were determined by competitive enzyme-linked immunosorbent assay (ELISA) using a monoclonal antibody (MAb) to feline infectious peritonitis virus (FIPV) Type II and neutralizing test using Type II FIPV as challenge virus. A total of 1,079 cat serum samples were tested by indirect fluorescent antibody (IFA) assay for FIPV Type II antigen, all 42 sample from natural cases of FIP, 138 of 647 (21.3%) from cases with some chronic diseases and 57 of 390 (14.6%) from apparently non-diseased cases were positive. Of the 42 cases with FIP, 29 (69%) and 13 (31%) were found to have infection with FIPV Types I and II, respectively. Of the cases with chronic diseases, 111 (80.4%) were shown to have infection with FIPV or FECV Type I, while 14 (10.1%) with FIPV or FECV Type II. All of the 57 apparently non-diseased cases seemed to have been infected with FIPV or FECV Type I. These results indicated that feline coronavirus Type I is more high prevalent in Japan.

Animals↗

PubMed1992

Flow cytometric DNA analysis of lung cancer cell lines.

Tumor DNA content (ploidy) was analyzed by use of flow cytometry (FCM) in 17 lung cancer cell lines which were subcultured in our laboratory. The study included 6 adenocarcinomas, 2 squamous cell carcinomas, 1 adenosquamous cell carcinoma, 5 large cell carcinomas, and 3 small cell carcinomas. Of the 17 lung carcinoma cell lines, 15 revealed aneuploid patterns with DNA index above 1.1, whereas one had diploid. The mean DNA index (DI) in adenocarcinoma, was 1.34 +/- 0.09, DI 1.6, in squamous cell carcinoma, DI 1.0 in adenosquamous cell carcinoma, DI 1.70 +/- 0.66 in large cell carcinoma, and DI 1.29 in small cell carcinoma. Of the 17 cell lines, three lines showed multiploid patterns with clinically poor prognosis and indicated heterogeneity. Flow cytometric DNA analysis using lung cancer cell lines could provide further basic study of lung cancer cells and give a useful information on the degree of the malignancy clinically.

DNA, Neoplasm↗

PubMed1992

Histochemical detection of lipid peroxidation in human gastrointestinal, mammary and renal carcinomas.

Constitutional lipid peroxidation in randomly selected 32 cases of clinically advanced carcinoma from human gastrointestinal tract (20 cases), breast (8 cases) and kidney (4 cases) was examined histochemically in frozen sections using cold Schiff's reagent. Only two cases of gastrointestinal carcinoma were positive by the reagent. Non-cancerous parenchymal cells were negative. These findings suggest that detectable constitutional lipid peroxidation seldom occurs in either cancerous or normal tissues. The capacity for normal and neoplastic tissues to undergo lipid peroxidation was also studied by incubation with an iron-NADPH pro-oxidant system. Normal parenchymal cells showed, to various degrees, a positive reactivity. In gastrointestinal carcinoma, 6 out of 7 cases of well differentiated adenocarcinoma reacted positively, whereas 2 out of 8 cases of moderately to poorly differentiated adenocarcinoma disclosed weakly positive reactions. Mucinous adenocarcinomas (4 cases) were all negative. Signet-ring cell carcinoma (1 case) was positive. One out of 8 cases of breast cancer also showed positive reaction. Four renal cell carcinomas were all negative. Cancer cells have lower capacity to undergo lipid peroxidation than normal cells, when the iron-NADPH pro-oxidant system was employed. In gastrointestinal carcinoma, the ability to undergo lipid peroxidation by the iron-NADPH pro-oxidant seems to be correlated with their histological differentiation. This fact may suggest that differences in lipid composition or the NADPH enzyme system exist between well differentiated and poorly differentiated gastrointestinal malignancies.

Adult↗

PubMed1992

Significance of urinary albumin index in the urine collected arbitrarily in the morning.

To evaluate urinary albumin index (UAI), the relationship between albumin excretion rate (AER) in the urine stored for 24 h and UAI in the urine collected arbitrarily on the morning of the same day was studied in 123 inpatients. The patients were admitted to our hospital from September 1, 1988 to August 31, 1989, consisting of 67 non-insulin dependent diabetics (Group 1), 40 patients with collagen disease (Group 2), and 16 patients with primary renal disease (Group 3). The relationship between log(e) AER and log(e)UAI was plotted on a graph. Pearson's rank correlation coefficients of Groups 1-3, Group 1, Group 2, and Group 3 were as follows: r = 0.725, r = 0.691, r = 0.855, and r = 0.611, respectively. The formula obtained by using Pearson's rank correlation coefficients to estimate log(e)AER from log(e)UAI in 123 cases of Groups 1-3, 67 cases of Group 1, 40 cases of Group 2, and 16 cases of Group 3 were: log(e)AER/log(e)UAI = 0.815, log(e)AER/log(e)UAI = 0.860, log(e)AER/log(e)UAI = 0.830, log(e)AER/log(e) = 0.722, respectively. In the present study, log(e)UAI was found to correlate well with log(e)AER. As AER is generally accepted to be the most reliable index to know the stage of albuminuria, UAI is considered to be clinically useful.

Adult↗

PubMed1992

Microvascular architecture of the lingual papillae in the Japanese monkey (Macaca fuscata fuscata).

The microvascular architecture of all kinds of lingual papillae in the Japanese monkey was investigated on plastic corrosion casts and epithelium-separated specimens under a scanning electron microscope. Three kinds of the filiform papillae were observed; the circularly-arranged papillae with a small papilla in the center on the lingual apex, a simple large conical papilla with a bilateral pair of spines on the lingual body and the aggregated filiform papillae on the top of an epithelial projection on the lingual radix. Five to eight capillary loops were arranged in a circle of the above filiform papillae on the lingual apex. Arterioles ascended in the filiform center on the lingual body to form an intrapapillary network in the shape of a large cone, from which capillary loops were observed only on the top surface of the papilla. Capillary loops arising from the subepithelial capillary network in the epithelial projection were distributed to each filiform papilla on the lingual radix. Globular fungiform papilla on the lingual apex were supplied by capillary loops radiating from the intrapapillary capillary network. Cylindrical fungiform papillae on the lingual body were supplied by capillary loops only on the top surface of each fungiform papilla without any loop formation on the lateral surface. Four vallate papillae, a medial and lateral pair, were supplied by arterioles ascending in the papillary center to form an intrapapillary capillary network, from which capillary loops were sent off on the top surface of the papilla and formed a network in the lateral surface. Each foliate papilla was supplied by an arteriole passing through each papillary center along the long axis and 5 or 6 capillary loops from the arteriole on the frontal section. Every lingual papilla was supplied by a characteristic microvascular pattern, which correlated closely with the location of the papillae and areas reflecting the regional role of the tongue movement, especially in the filiform and fungiform papillae.

Animals↗

PubMed1992

Synergistic effect of 1,25-dihydroxyvitamin D3 and retinoic acid in inducing U937 cell differentiation.

We examined the effects of retinoic acid (RA), 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3), and its synthetic analogue, 22-oxa-1,25-(OH)2D3, on differentiation of U937 cells by studying the cellular growth, surface marker expression and cytosolic free Ca2+ concentration ([Ca2+]i). RA inhibited cellular growth but did not induce expression of Mo2 (CD14), a monocyte/macrophage specific surface marker. To the contrary, 1,25-(OH)2D3 did not inhibit cellular growth, but increased CD 14-positive cells. Simultaneous addition of 1,25-(OH)2D3 and RA had no additive effect on cellular growth inhibition or CD14 expression. With regard to [Ca2+]i, however, 5 days' incubation with either of them increased the basal [Ca2+]i level and induced U937 cells to respond to formyl-methionyl-leucyl-phenylalanine (FMLP). When the cells were incubated with both 10(-6) M RA and 10(-8) M 1,25-(OH)2D3, basal [Ca2+]i was higher and FMLP caused a greater increase in [Ca2+]i than when only RA or 1,25-(OH)2D3 was added. These data suggest that RA and 1,25-(OH)2D3 induce monocytoid differentiation in U937 cells through different pathways and act synergistically in the differentiation process. The 22-oxa-1,25-(OH)2D3 induced CD14 expression, basal [Ca2+]i increase and [Ca2+]i response to FMLP, but did not cause cellular growth inhibition in U937 cells, and in these points, 22-oxa-1,25-(OH)2D3 exhibited no significantly different effects from 1,25-(OH)2D3. Thus, 22-oxa-1,25-(OH)2D3 has the same potent activity as 1,25-(OH)2D3 in inducing differentiation of U937 cells.

Antigens, CD↗

PubMed1992

[Evaluation of school dental health activities in Hiraizumi primary school, Iwate prefecture].

The purpose of this study was to evaluate the health activities in Hiraizumi primary school, Iwate prefecture. As a result of intensive dental health activities from 1978 to 1990, which consisted of tooth brushing instruction by class, dental education for the schoolchildren and their guardians, utilization of fluoride mouth rinsing (once a week), and, by following a model school of caries prevention designated by the Ministry of Education et al., the oral health status of the Hiraizumi primary schoolchildren improved significantly compared with those of the Ohya primary schoolchildren who followed the routine school dental health activities. The results of questionnaires, taken from both primary schoolchildren in 1986 and 1989, show that the oral health behavior of the Hiraizumi primary schoolchildren also improved.

Age Factors↗

PubMed1992

[Studies on caries of Ishibashi rat--III. Experimental caries in Ishibashi rat].

Dental caries was experimentally induced in the Ishibashi rats (ISR) by feeding them with conventional diets or with caries-producing diets, and the pattern and severity of their induced carious lesions were compared with those of the Sprague-Dawley rats (SD). Simultaneously, serum antibody titers against Streptococcus mutans and calcium and phosphorus concentration in the sera and in the femurs were compared between the ISR and SD. The results were as follows: 1. When judged by cavities, ISR showed a higher carious incidence and average number of cavities per one rat than the SD, whichever diet the rats were fed. 2. When judged by fissure caries observed on the thin sections of the teeth, both the carious incidence and average number of fissure lesions in the ISR were not always high compared with those in the SD, and there seemed to be a great variation of caries-susceptibility in the ISR. 3. Caries in the ISR seemed to be more progressive than that in the SD. 4. There were no differences in the serum antibody titers against the S. mutans between the ISR and SD. 5. No differences in the concentration of calcium and phosphorus in the sera and femurs were observed between the ISR and SD, whichever diet they were fed.

Animals↗

PubMed1992

[Study on screening of high-caries-risk children by using number of DMFT at 6 years of age].

This study was carried out to contrive a screening level and select high-caries-risk school-children by using the number of dmft in the deciduous canines and molars at 6 years of age. The screening level was established at 9 dmft by analyzing the longitudinal caries data from 119 primary schoolchildren in Tomisato, Chiba Prefecture. Thirty-three percent of the high-caries-risk children, selected by the application of this screening level to the other three primary schools, were predicted that the mean number of DMFT would be 6 or more at 11 years of age. However, this screening level was not available for the two schools which had been adopting a fluoride mouth rinsing program because of their low caries experience at 11 years of age.

Age Factors↗