Search PubMed⌕ Search

Biomedical subjects

T Murase

Publications and source records attributed to T Murase.

At least 271 records · Page 15Linked to original sources

Ontogeny of the response of the hypothalamo-pituitary-adrenal axis to maternal immobilization stress in rats.

In this study we investigated the response of the rat fetal hypothalamo-pituitary-adrenal (HPA) axis to an acute maternal stress in late gestation. On day 20 of gestation, pregnant rats were exposed to forced immobilization stress for up to 60 min. In mothers, a significant increase in plasma ACTH and corticosterone(B) was observed at 20 and 60 min. The ACTH content in the maternal pituitary decreased significantly at 60 min. Fetal blood pH was decreased by the maternal stress, showing a hypoxic condition of the fetus. Fetal plasma ACTH increased transiently at 20 min. Fetal plasma B increased at 20 and 60 min. ACTH in the fetal pituitary and the placenta did not show marked changes due to the maternal stress. Pregnant rats on day 18-21 of gestation were subjected to a 20 min maternal stress. In the basal condition without stress, fetal plasma ACTH and B showed parallel ontogenic patterns, having a peak value on day 19 of gestation. Fetal plasma ACTH as well as plasma B were increased significantly by the maternal stress at all points evaluated. These results indicate that fetal hypoxia is important in stress transmission to the fetal HPA axis in this type of maternal stress, and the fetal HPA axis responds to the stress as early as day 18 of gestation.

Adrenocorticotropic Hormone↗

Prolactin secretion in patients with idiopathic diabetes insipidus.

It has been demonstrated that hyperprolactinemia is sometimes present even in patients with idiopathic diabetes insipidus (DI). In this study, we examined the responses of serum prolactin (PRL) to hypertonic saline infusion and TRH injection in 11 patients with idiopathic DI diagnosed by clinical examinations. Serum sodium in these patients (147.5 +/- 3.2 mEq/L) was significantly higher at baseline than in normal subjects (139.7 +/- 2.4 mEq/L). The plasma arginine vasopressin (AVP) level was significantly lower in DI (0.42 +/- 0.24 pg/ml) at baseline than in normal subjects (2.53 +/- 1.03 pg/ml). However, the serum PRL level in both groups did not differ significantly except in one patient with idiopathic DI (35.6 ng/ml). There was no significant correlation between the basal serum sodium and basal serum PRL in either group. After an infusion of hypertonic saline, the serum sodium level gradually increased to 155.6 +/- 3.4 mEq/L in DI and to 146.5 +/- 4.3 mEq/L in the normal subjects. However, this increase did not affect PRL secretion in either group. PRL response to TRH was essentially normal in all patients with idiopathic DI. These results indicate that the secretion of PRL is not generally affected by chronic mild hypernatremic hypovolemia in the patients with idiopathic DI.

Adolescent↗

Does chylomicronemia cause atherosclerosis?

Does chylomicronemia cause atherosclerosis? To directly address this clinically important problem, we conducted experiments in guinea pigs which lack apolipoprotein CII and develop chylomicronemia when they are fed a high-fat diet. After 6-12 months on a high-fat diet, guinea pigs were sacrificed, and subjected to histopathological and ultrastructural examination. Both the aorta and the coronary arteries revealed no atherosclerotic changes in all 4 animals examined: the endothelium was intact, and neither lipid-laden foam cells nor migrating cells were present within the arterial wall. Our studies indicate that chylomicronemia does not predispose to atherosclerosis.

Animals↗

[A case of RAEB-t treated by G-CSF showing complete remission after MST-16 treatment for subsequent reversible leukemia].

A seventy-five-year-old female with general fatigue, high fever and anemia was admitted. Her chest X-ray film revealed pneumonia. She was diagnosed as RAEB-t with the normal karyotype by peripheral blood film and bone marrow aspiration; 125 micrograms/ml of G-CSF was administered s.c. daily in order to increase neutrophil count because of the prolongation of pneumonia. Her blast cells in both peripheral blood and bone marrow showed a remarkable increase by G-CSF. After the cessation of G-CSF administration, blast cells decreased rapidly, and neutrophil count in the peripheral blood increased. Her pneumonia was then cured. After 5 months of stable hematological state, 60% of her bone marrow cells became occupied by blast cells again. So 2 consecutive courses of 14 days p.o. administration of 1,200 mg MST-16/day were tried. Three months after the first MST-16 trial, her bone marrow showed complete remission (CR) which lasted about 4 months. But she died of sepsis after the first relapse. Her bone marrow in CR still revealed several features of dyspoiesis.

Acute Disease↗

[Hormonal treatment of carcinoma of the prostate].

Efficacy of orchiectomy and intravenous administration of diethylstilbestrol diphosphate (DESP) for the treatment of prostatic carcinoma was evaluated on 184 patients treated between 1975 to 1989. The patients were between 49 to 88 years old with a mean age of 73.4 +/- 8.3 years. Clinical stage was A in 9.8%, B in 12%, C in 26.6% and D in 51.6%. The histologically well, moderately and poorly differentiated adenocarcinoma were observed in 20.9, 29.4 and 49.7%, respectively. The 5-year survival rate of stage A, B, C and D calculated with the Kaplan-Meier method were 90, 49, 60 and 34%, respectively. The 5- and 10-year survival rate of the patients who had received orchiectomy was 53 and 24%, respectively, while that of the patients without orchiectomy was 38 and 14%, respectively. The 5 and 7-year survival rate of the patients treated with intravenous administration of DESP was 54 and 34%, respectively while that of the patients without DESP was 46 and 31%, respectively. These findings suggest that orchiectomy and intravenous administration of DESP in any form prolonged patient survival compared with only oral administration of estrogens or antiandrogens. Reactivation was seen in 24 (40%) of the 60 patients under sufficient observation. Clinical relapse occurred within an average of 32.3 +/- 26.4 months after primary hormonal manipulation. The average time to relapse in stage D was shorter than that in stage B and C. Reactivation was observed in the patients on interrupted treatment earlier than in the patients on continuous administration of drugs. Cardiovascular death followed by endocrine therapy was 7.4% in this study.

Adenocarcinoma↗

Grade 3 bladder cancer with lamina propria invasion (pT1): characteristics of tumor and clinical course.

To determine the clinical characteristics of grade 3 tumors with lamina propria invasion (pT1), we reviewed the data of 217 patients with superficial bladder cancer who had initially been treated by transurethral resection (193 patients) and fulguration (4), supravesical resection (13) or partial cystectomy (7). We classified the patients into four groups according to histological grade and stage of disease: group 1) grade 0 or 1, pTa tumors (n = 58); group 2) grade 2, pTa tumors (n = 106); group 3) grade 2, pT1 tumors (n = 30); and group 4a) grade 3, pT1 tumors (n = 23). Grade 3, pT1 tumors were significantly related to nonpapillary growth (p = 0.0002), multiple tumors (p = 0.005) and irritative bladder symptoms (p = 0.01). The 5-year progression rates were 0% for group 1, 5% for group 2, 8% for group 3, and 18% for group 4a. The respective 5-year survival rates were 97%, 91%, 83% and 79%. All five patients with grade 3, pT1 tumors who had originally undergone total cystectomy (group 4b) remained alive free of disease for a median follow-up 57 months, establishing a far better survival rate than that for group 4a. These findings show that patients with grade 3, pT1 tumors face a high probability of progression and poor chance of survival. Immediate radical treatment is indicated when tumors recur after initial transurethral resection.

Aged↗

The effect of an acute stress in late pregnancy on hypothalamic catecholamines of the rat fetus.

Prenatal stress in the last trimester of pregnancy induces permanent disorders in sex-specific differentiation of the brain in rats. In order to determine the neuroendocrine response of the fetal hypothalamus to the maternal stress, we investigated the temporal change in fetal hypothalamic catecholamines when their mothers were exposed to an acute stress. On day 20 of gestation, pregnant rats were subjected to forced immobilization and sacrificed at 0, 30, 60, 120 and 180 minutes. Plasma corticosterone reached a peak at 60 minutes of stress in mothers and fetuses. Hypothalamic norepinephrine and epinephrine decreased at 120 and 180 minutes of stress in mothers, whereas in fetuses, hypothalamic norepinephrine decreased at 120 and 180 minutes of stress, and dopamine also showed a tendency to decrease. These results suggest that maternal stress in late pregnancy decreases fetal hypothalamic norepinephrine which is involved in androgen-dependent sex differentiation of the brain.

Androgens↗

[High-dose chemotherapy with autologous bone marrow transplantation as treatment for relapsing testicular cancer].

In testicular cancer the tumor shows a high response rate to chemotherapy with dose responsiveness. However, when it is treated with high-dose chemotherapy, myelosuppression is severe. To overcome this problem, autologous bone marrow transplantation has been attempted. This is a report of an 18-year-old man with advanced nonseminomatous testicular cancer (stage IIB, embryonal carcinoma and teratoma) with relapse after first course of therapy. He was treated with high-dose chemotherapy (etoposide 1,750 mg/m2, cisplatin 200 mg/m2, cyclophosphamide 60 mg/kg) and with autologous bone marrow transplantation. This patient has been in complete remission for more than 15 months without severe side effects or complications. We consider this a striking response to treatment in an early phase of relapsing testicular cancer.

Adolescent↗

Suppression of lipoprotein lipase in 3T3-L1 cells by a mediator produced by SEKI melanoma, a cachexia-inducing human melanoma cell line.

Production of a cachexia-inducing factor(s) by the SEKI melanoma cell line, established from a human melanoma, has been well documented. Conditioned medium from cultures of this melanoma cell line contains a factor(s) that inhibits the activity of lipoprotein lipase (LPL) in fully differentiated 3T3-L1 adipocytes. The mode of inhibition of this enzyme by the factor, i.e. its dose-dependency and time course, is very similar to that of LPL-inhibition by a macrophage-derived cachexia-inducing factor, cachectin/tumor necrosis factor (cachectin/TNF). However, the conditioned medium of SEKI melanoma cells does not contain any immuno-reactive substances reactive in enzyme-linked immunosorbent assay (ELISA) with anti-cachectin/TNF antibody, or with anti-interleukin 1 alpha or beta antibodies. This LPL-suppression factor present in the conditioned medium seems to be a peptide because of its heat-lability and apparent molecular weight of more than 25,000. The conditioned media from cultures of four other different cell lines were found to show no significant suppression of LPL activity. These results imply that SEKI melanoma cells produce a cachexia-inducing factor(s) similar to cachectin/TNF but that the molecule involved is different.

Animals↗

Oxidation-labile subfraction of human plasma low density lipoprotein isolated by ion-exchange chromatography.

We isolated subfractions of human plasma low density lipoprotein (LDL) using ion-exchange chromatography. Plasma LDL from normolipidemic subjects were applied to a DEAE Sepharose 6B column. After elution of the bulk of LDL at 150 mM NaCl (the major fraction), the residual LDL was eluted at 500 mM NaCl and designated as the minor fraction. The minor fraction, only less than 1% of total LDL, tended to be somewhat similar in certain properties to oxidized LDL, e.g., an increased negative charge, higher protein/cholesterol ratio, and a higher flotation density than native LDL. These results were consistent with data reported by Avogaro et al. (1988. Arteriosclerosis. 8: 79-87). However, assays of 125I-labeled LDL binding activity for LDL receptors equal to that of the major fraction. Incorporation of [14C]oleate into cholesteryl ester [acyl-CoA:cholesterol acyltransferase (ACAT) activity] in mouse peritoneal macrophages incubated with the minor fraction was only slightly greater than that with the major fraction. Incubation of the minor fraction with 0.5 microM Cu2+ caused a remarkable stimulation of ACAT activity, while stimulation by the major fraction required incubation with 5 microM Cu2+, suggesting that the minor fraction was relatively labile to oxidation. The minor but definite presence of a plasma LDL subfraction more negative and susceptible to oxidation implicates the possibility of its association with atherogenesis.

Arteriosclerosis↗

Apolipoprotein E and lipoprotein lipase secreted from human monocyte-derived macrophages modulate very low density lipoprotein uptake.

We investigated the roles of lipoprotein lipase and apolipoprotein E (apoE) secreted from human monocyte-derived macrophages in the uptake of very low density lipoproteins (VLDL). ApoCII-deficient VLDL were isolated from a patient with apoCII deficiency. The lipolytic conversion to higher density and the degradation of the apoCII-deficient VLDL by macrophages were very slight, whereas the addition of apoCII enhanced both their conversion and degradation. This suggests that the lipolysis and subsequent conversion of VLDL to lipoproteins of higher density are essential for the VLDL uptake by macrophages. VLDL incubated with macrophages obtained from subjects with E3/3 phenotype (E3/3-macrophages) showed a 17-fold greater affinity in inhibiting the binding of 2 micrograms/ml 125I-low density lipoprotein (LDL) to fibroblasts than native VLDL, whereas the incubation of VLDL with macrophages obtained from a subject with E2/2 phenotype (E2/2-macrophages) did not cause any increase in their affinity. Furthermore, 3 micrograms/ml 125I-VLDL obtained from a subject with E3/3 phenotype were degraded by E3/3-macrophages to a greater extent than by E2/2-macrophages (2-fold), indicating that VLDL uptake is influenced by the phenotype of apoE secreted by macrophages. From these results, we conclude that both lipolysis by lipoprotein lipase and incorporation of apoE secreted from macrophages alter the affinity of VLDL for the LDL receptors on the cells, resulting in facilitation of their receptor-mediated endocytosis.

Apolipoprotein C-II↗

Pancreatic cytokeratin: an antigen of pancreatic exocrine cell autoantibodies in type 1 (insulin-dependent) diabetes mellitus.

Autoantibodies reacting with human pancreatic exocrine cells were investigated by immunofluorescent techniques in 107 patients with Type 1 (insulin-dependent) diabetes mellitus, 20 first-degree relatives of the Type 1 diabetic patients, 347 patients with Type 2 (non-insulin-dependent) diabetes, 34 with alcoholic pancreatitis, 26 with rheumatoid arthritis and 107 normal control subjects. Both immunoblotting analysis and double-immunostaining methods were used to characterize the antigens targeted by the pancreatic exocrine cell autoantibodies. Sera positive for human pancreatic exocrine cell cytoplasm, producing a "fine fibrillar" pattern, were found in 21% (23/107) of the Type 1 diabetic patients. The autoantibodies were present in 39% (15/38) of Type 1 diabetic patients diagnosed within 3 months, and the prevalence decreased with duration of diabetes. The antibodies were of the IgM class in 87% (13/15) of recent-onset Type 1 diabetes cases, but IgG-autoantibodies became more prevalent with increasing duration of diabetes. Three out of 347 (0.9%) Type 2 diabetic patients and 4 of 20 (20%) first-degree relatives of Type 1 diabetic patients had autoantibodies targeted against pancreatic exocrine cells. None of the patients with alcoholic pancreatitis or rheumatoid arthritis and none of the control subjects had these antibodies. Immunoblotting analysis and double-immunostaining demonstrated that the autoantibodies reacted with 40 kilodalton cytokeratin in pancreatic exocrine cell cytoplasm. The antibody was absorbed by the Triton X-100-insoluble fraction of pancreatic extract. These results indicate the presence of distinct autoantibodies to pancreatic exocrine cells in Type 1 diabetes. This suggests the provocative concept that the cytoskeletal system of pancreatic exocrine cells is involved in the pathogenetic process of Type 1 diabetes.

Adolescent↗

Relationships among islet cell antibodies, residual beta-cell function, and metabolic control in patients with insulin-dependent diabetes mellitus of long duration: use of a sensitive C-peptide radioimmunoassay.

Relationships among islet cell antibodies (ICA), residual beta-cell function, and metabolic control were studied in 60 insulin-dependent diabetics (IDDs) of long duration (6 to 31 years). Sensitive C-peptide immunoreactivity (CPR) and ICA assays with limits of 0.017 nmol/L and 5 Juvenile Diabetes Foundation (JDF) U, respectively, demonstrated that baseline (0.16 +/- 0.02 nmol/L, mean +/- SE, n = 26), as well as maximum CPR values (0.34 +/- 0.05 nmol/L), during 100-g oral glucose tolerance tests (OGTT) in ICA-positive IDDs were significantly higher than corresponding values in ICA-negative ones (baseline values, 0.10 +/- 0.01 nmol/L, P less than .05; maximum values, 0.20 +/- 0.04 nmol/L, P less than .01, n = 34). Negative correlation was observed between increment of serum CPR and metabolic control indices, including fasting blood glucose (FBG) and HbA1c levels (P less than .05). In addition, ICA-positive insulin-dependent diabetes mellitus (IDDM) patients had lower values of FBG (8.2 +/- 0.4 mmol/L, P less than .01 v ICA-negative IDDs) and HbA1c (9.2% +/- 0.2%, P less than .05 v ICA-negative IDDs) than ICA-negative ones (FBG, 9.9 +/- 0.4 mmol/L; HbA1c, 9.8% +/- 0.2%). These results indicate that minute CPR responses to OGTT detected by sensitive methods may represent residual pancreatic beta cells, which may contribute to ICA generation and good metabolic control in IDDs of long duration.

Autoantibodies↗

Assessment of bull fertility using a mucus penetration test and a human chorionic gonadotrophin stimulation test.

The relative predictive abilities of an in vitro mucus penetration test and a human chorionic gonadotrophin (hCG) stimulation test were compared for assessing bull fertility. Cervical mucus was collected from 22 Holstein cows and then stored in liquid nitrogen. Semen was collected from 13 Holstein bulls and evaluated for standard semen parameters. The mucus penetration test was performed with fresh ejaculates, and the results were expressed as the distance traveled by the vanguard spermatozoa during incubation at 38 degrees C for 10 min. Increases in plasma testosterone levels were determined by a ratio of testosterone concentration before and after hCG injection. Sperm motility and mucus penetration were significantly correlated with the conception rate. However, no significant correlation was confirmed between the increased plasma testosterone levels and conception rate. The results indicate that the mucus penetration test is an effective method for predicting the fertility of bulls.

Journal Article↗

Impact of methodological factors on sperm penetration into cervical mucus in cattle.

The aim of this study was to investigate the influence of methodological factors on the interaction of bovine spermatozoa and homologous cervical mucus. Cervical mucus was obtained from three cows during estrus. To evaluate the penetration ability of frozen-thawed semen samples of five different bulls, fresh mucus as well as frozen-thawed mucus, stored for 1, 10 or 30 d in liquid nitrogen, were used. Penetration assays were performed at 38 degrees C for 10 min, and the most advanced spermatozoon was located and the distance determined. Semen parameters were examined by a computer-assisted videomicrographic system. Conservation of mucus in liquid nitrogen for up to 30 d did not influence the results of the penetration assay. In contrast, the mucus of individual cows showed significant differences in the migration distance of spermatozoa. Sperm concentration, mean velocity and number of forward moving spermatozoa were significantly correlated with mucus penetration. These results demonstrated that the mucus penetration assay in cattle can be performed by dividing a mucus sample from a cow into many portions and storing the sample in liquid nitrogen.

Journal Article↗

Cholesterol-free diet with a high ratio of polyunsaturated to saturated fatty acids in heterozygous familial hypercholesterolemia: significant lowering effect on plasma cholesterol.

We have studied the effect of diet therapy on plasma lipoprotein metabolism in heterozygous familial hypercholesterolemia. Seven patients with a mean plasma cholesterol concentration of 323 +/- 67 mg/dl were hospitalized and kept on a cholesterol-free diet for as long as 11 days without any medication. The content of dietary cholesterol was approximately 1.4 mg a day, and dietary fat, carbohydrate and protein comprised 18.0, 69.2 and 12.8% of calories, respectively. The ratio of polyunsaturated to saturated fatty acids (P/S) was 3.1. At the end of the study period, plasma cholesterol was lowered by 14.2%, from 323 to 277 mg/dl, and low density lipoprotein (LDL) cholesterol by 17.5% from 229 to 189 mg/dl. Using density gradient ultracentrifugation, the major change in LDL cholesterol was found to be in those fractions with a mean density between 1.034 and 1.042, where cholesterol concentrations decreased from 132 to 87 mg/dl (34%). These results indicate that diet therapy with free-cholesterol and a high ratio of P/S is highly effective in controlling plasma cholesterol levels in heterozygous familial hypercholesterolemia.

Adult↗