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T Murase

Publications and source records attributed to T Murase.

At least 163 records · Page 9Linked to original sources

Centrally administered neuropeptide FF inhibits arginine vasopressin release in conscious rats.

There is evidence indicating that neuropeptide FF (NPFF) is an endogenous modulator of opioid systems. In the present study, we investigated the effect of centrally administered NPFF on arginine vasopressin (AVP) release in conscious rats. The plasma AVP increase in response to either hyperosmolality [i.p. injection of hypertonic saline (600 mosmol/kg)] or hypovolemia [i.p. injection of polyethylene glycol (PEG)] was significantly blunted when NPFF was injected into the lateral ventricle so that the given drug could act at the hypothalamus and also reach the brain stem (hypertonic saline with 10 micrograms/rat NPFF, 3.28 +/- 0.48 pg/ml; hypertonic saline alone, 7.85 +/- 1.78 pg/ml; PEG with 10 micrograms/rat NPFF, 4.07 +/- 1.40 pg/ml; PEG alone, 8.25 +/- 1.90 pg/ml). The plasma AVP increase in response to PEG-induced hypovolemia was also attenuated significantly and more potently when NPFF was injected into the cisterna magna so that the given drug could be readily accessible to the dorsal medulla where the nucleus of solitary tract is located (10 micrograms/rat; 2.71 +/- 0.14 pg/ml). In contrast, the NPFF injected into the cisterna magna had no significant effect on hyperosmolality-induced AVP release. Treatment with naloxone (10 mg/kg BW, sc) significantly reversed the inhibitory effects of NPFF on AVP release. These results suggest that central NPFF might play an inhibitory role via the hypothalamus in the osmoregulation of plasma AVP and via both the hypothalamus and the nucleus of solitary tract in the baroregulation, and that the intrinsic opioid systems are involved in the action of NPFF.

Amino Acid Sequence↗

Oxidative damage and enhanced erythrophagocytosis in canine erythrocytes infected with Babesia gibsoni.

Oxidative damage to canine erythrocytes infected with Babesia gibsoni was investigated. B. gibsoni was cultured together with erythrocytes from normal dogs. When parasitemia reached a peak level, concentrations of both methemoglobin (metHb) and malondialdehyde (MDA), an end product of lipid peroxidation, in erythrocytes were significantly higher than at cultivation Day 0. In addition, B. gibsoni-infected dogs with high parasitemia showed significant increases of both metHb and MDA concentration in erythrocytes compared to those in uninfected dogs. Furthermore, erythrocytes from parasitized culture were more susceptible to phagocytosis by bone marrow macrophages from normal dogs than erythrocytes from the control culture. In addition, macrophages ingested not only parasitized erythrocytes but also non-parasitized cells. These results suggested that oxidative damage to erythrocytes was induced by the multiplications of B. gibsoni, and that non-parasitized erythrocytes were also exposed erythrocytes oxidative stress during the infection by B. gibsoni.

Animals↗

Hypertriglyceridemia and low HDL cholesterol in Japanese patients with NIDDM.

Diabetes is frequently associated with the combination of hypertriglyceridemia and low HDL cholesterol level, a known risk factor for cardiovascular disease. We evaluated the frequency of elevated serum triglyceride and the reduced HDL cholesterol levels in Japanese male NIDDM patients. Hypertriglyceridemia (>1.69 mmol/l) and low HDL cholesterol level (<0.91 mmol/l) were frequently found in Japanese male (NIDDM patients (30.4 and 14.2%, respectively). The combined abnormality, i.e., hypertriglyceridemia with concomitant low HDL cholesterol level, was more common in patients with poor glycemic control. We observed that inpatient diet therapy markedly reduced serum triglyceride but serum HDL cholesterol did not change significantly. This is in marked contrast to primary hypertriglyceridemia, in which HDL cholesterol level generally increases in parallel with a reduction in serum triglyceride level. We discuss the defective removal of triglyceride-rich lipoproteins and ineffective HDL production caused by lipoprotein lipase (LPL) deficiency. We also discuss possible correction of this combined abnormality by certain maneuvers that increase LPL activity.

Adult↗

Risk factor analyses for macrovascular complication in nonobese NIDDM patients. Multiclinical Study for Diabetic Macroangiopathy (MSDM).

To examine the characteristic features of risk factors for macroangiopathy (MA) in nonobese Japanese NIDDM patients, 899 NIDDM patients with and without MA were registered from 40 facilities. Of these, 386 subjects were identified as having any form of MA (total MA); these included 211 with ischemic heart disease (IHD), 163 with cerebrovascular disease (CVD), and 77 with peripheral vascular disease (PVD). Univariate analyses revealed the following common risk factors for total MA, IHD, CVD, and PVD: age, hypertension, systolic blood pressure (sBP) or diastolic blood pressure (dBP), duration of diabetes, diabetic microangiopathy (retinopathy, nephropathy, and neuropathy), low HDL cholesterol level, and higher LDL cholesterol/HDL cholesterol ratio. Additional significant risk factors for specific conditions were also identified, respectively, as male sex for total MA, IHD, and PVD, smoking for IHD and PVD, and high fasting plasma glucose level for total MA and CVD. With stepwise multivariate logistic regression analysis, older age, duration of diabetes, smoking, and low LDL cholesterol/HDL cholesterol ratio were identified as significant and independent risk factors for total MA, IHD, CVD, and PVD. Other risk factors identified were high dBP for IHD, CVD, and PVD, high sBP for total MA, and low BMI for PVD. These results clearly demonstrated that duration of diabetes, smoking, hypertension, and dyslipidemia are major risk factors for MA in NIDDM patients. Since the mean BMI was similar for both groups (approximately 23 kg/m2) and there were no significant differences in immunoreactive insulin levels before and after 75-g oral glucose challenge testing, obesity and hyperinsulinism at the time of the analyses were not considered to play an important role for the pathogenesis of MA in Japanese NIDDM patients. By using the chi 2 test, cutoff points were determined for six of the most commonly measured risk factors. The cutoff point was the level beyond which a significantly higher prevalence of MA occurred. The cutoff points (rounded slightly upward in some cases) for fasting plasma glucose, sBP, dBP, serum total cholesterol level, serum triglyceride level, and BMI were 140 mg/dl, 140 mmHg, 80 mmHg, 180 mg/dl, 120 mg/dl, and 23 kg/m2, respectively. When these cutoff points were used as control criteria, the prevalence of MA was significantly lower in subjects whose risk factor measurements remained under the proposed control criteria for four or more of the six variables. In conclusion, in nonobese NIDDM patients, age, hypertension, and dyslipidemia were found to be risk factors for MA. Duration of diabetes was also demonstrated as an independent risk factor, indicating the close association of deranged glucose metabolism with the pathogenesis of MA in NIDDM patients. It seems to be crucial to control these risk factors for the prevention of MA in NIDDM patients.

Aged↗

Small doses of subcutaneous insulin as a strategy for preventing slowly progressive beta-cell failure in islet cell antibody-positive patients with clinical features of NIDDM.

We report a pilot study to determine the preventive effect of small doses of insulin injected subcutaneously on slowly progressive beta-cell damage in islet cell antibody (ICA)-positive patients with apparent NIDDM. Ten NIDDM patients who were ICA' were divided into two groups of five. In the insulin group (age: 51 +/- 8 years [mean +/- SD], sex: 3 men and 2 women), intermediate-type insulin (3-16 U/day) was given once or twice daily as a subcutaneous injection. The sulfonylurea (SU) group (age: 48 +/- 11 years, sex: 3 men and 2 women) was initially treated with a SU agent. Changes in beta-cell function, as indicated by serum C-peptide responses and blood glucose values during a 100-g oral glucose tolerance test, as well as ICA and GAD antibody status, were evaluated for up to 30 months in both groups. ICA status became negative in four of five patients in the insulin group. ICA status did not become negative in any of the patients in the SU group (P = 0.047 vs. insulin group). ICA status was persistently positive in two patients whose beta-cell function eventually progressed to an insulin-dependent state and fluctuated in the remaining three patients. In the insulin group, GAD antibody status became negative in one of four initially GAD antibody-positive NIDDM patients. In the SU group, GAD antibody status was persistently positive in three NIDDM patients (NS vs. insulin group). The serum C-peptide response improved significantly within 6 and 12 months in the insulin group, whereas it decreased progressively in the SU group. The changes in C-peptide response were significantly different between the two groups at 6, 12, 24, and 30 months. Two-hour blood glucose and HbA1 values were unchanged in the insulin group, but they increased in the SU group. Subcutaneous small doses of insulin, resulting in a high rate of negative conversion of ICA and an improved serum C-peptide response, may be effective in treating ICA+ NIDDM patients who are at high risk for slowly progressive beta-cell failure.

Autoantibodies↗

Discrimination of grip force for preschool children aged 5 to 6 years.

The ability to discriminate grip force was investigated in 30 preschool children aged 5 to 6 years in an experiment controlling for motivation and muscle fatigue. The subjects were required to maintain a relatively high force during the discrimination with forces of the standard stimulus being 1.0, 2.0, and 3.0 kgf. Comparison stimuli changed at an interval of 0.1 kgf. Discrimination was measured in terms of the lower threshold, upper threshold, and interval of uncertainty. Since the statistical analyses indicated that there were no significant gender differences, data for boys and girls were combined. Although the upper and lower thresholds and the interval of uncertainty increased with the force required by the standard stimuli, Weber fractions did not remain constant when the stimulus intensity changed, unlike the findings in previous studies for adults.

Adult↗

Dose-dependent effect of niceritrol on plasma lipoprotein-a.

Lipoprotein-a, Lp(a), is a variant form of low density lipoprotein (LDL) that contains apolipoprotein-a, whose structure has 75-85% homology with plasminogen. Elevated plasma levels of Lp(a) are considered to be one of the independent risk factors for cardiovascular disease. We studied the effects of niceritrol, a nicotinic acid derivative, on plasma Lp(a) levels in 72 patients with hypercholesterolaemia. The dose of niceritrol was increased every 4 weeks, from 750 to 1500 and then to 2250 mg day-1. The final dose was adjusted to obtain a plasma cholesterol level less than 5.69 mmol l-1. Niceritrol led to significant decreases in plasma levels of median Lp(a), from 16.1 mg dl-1 (interquartile intervals, 8.7 to 32.8) to 11.1 mg dl-1 (interquartile intervals, 6.6 to 21), the mean reduction rate being 17.6%. In the group with pretreatment Lp(a) levels of over 20 mg dl-1, Lp(a) decreased by 10.0, 22.0 and 31.8% at the doses of 750, 1500, and 2250 mg day-1, respectively. In the group with levels less than 20 mg dl-1, only the dose of 2250 mg day-1 was effective in the reduction of Lp(a). The results suggest that the reduction of Lp(a) was dependent on the dose of niceritrol and on the pretreatment level of Lp(a). In conclusion, niceritrol is effective, in a dose-dependent manner, for reducing Lp(a) levels.

Aged↗

[Effect of preoperative oral 5-fluorouracil on cell cycle of advanced cervical squamous cell carcinoma].

Using flow cytometry, we examined the correlations between the tumor stage and the cell cycle in subjects with advanced cervical squamous cell carcinoma as well as between the changes of cell cycle caused by 5-FU and their prognoses. Before 5-FU treatment, 75.9 +/- 9.6% of the patients were at G1 phase, 16.8 +/- 3.9% at S and 7.3 +/- 4.5% at G2/M. The change of cell cycle was not accompanied by the progression of tumor stage. Sixteen patients received oral 5-FU (300 mg/day) for at least 2 weeks before operation. In the patients at stage I, the cell cycle was not changed even after 5-FU treatment. They have been cancer-free for 3 postoperative years. While early recurrence was found in 4 of 5 cases at stage II or III showing progression at G1, all 6 cases who had regressed or remained unchanged at G1 were free from recurrence (p = 0.0152). These results suggested that the cell cycle is not necessarily correlated with the progression of tumor stage in patients with this kind of carcinoma, and that the change of cell cycle due to preoperative oral 5-FU could be a predictive indicator for their prognoses. Especially for those with poor prognoses who had shown progression at G1, more potent adjuvant chemotherapy should be planned.

Administration, Oral↗

[Prognosis in stage a prostate cancer].

In 39 hospitals in the Tokai region of Japan, 815 cases with prostatic cancer were registered between 1988 and 1991, 91 of which (13.3%) were diagnosed as stage A. Eighty cases of stage A cancer were subclassified into stage A1 (33 cases) or stage A2 (47 cases). A detailed investigation was performed on these 80 subclassified cases with respect to tumor markers, treatment methods and prognosis. The tumor marker, prostate specific antigen (PSA) was positive in 18.5% of the A1 cases and 53.8% of the A2 cases. Endocrine therapy was administered in 45.5% of the A1 and 78.7% of the A2 cases. There was 1 (3.0%) case of progression in the stage A1 group, and 2 cases in stage A2 group. The 5-year survival rate was 97.0% for stage A1 and 88.6% for stage A2. The prognosis of prostatic cancer in stage A was fairly good in both the A1 and A2 subclasses in our series.

Aged↗

Overexpressions of c-fos/jun mRNA and their oncoproteins (Fos/Jun) in the mouse uterus treated with three natural estrogens.

To further understand hormonal carcinogenesis of natural estrogens (estrone, 17 beta-estradiol (E2) and estriol), we determined the expressions of c-fos/jun mRNA, and their oncoproteins (Fos/Jun) with intracellular localization in the uterus of ovarectomized mice treated with these estrogens. Mid-term chronic, as well as short-term assays were examined. Of three estrogens examined, mid-term chronic E2-treatment significantly increased the expression of c-fos/jun mRNA, and their oncoproteins (Fos/Jun). These were most prominently expressed in glandular cells of E2-treated mouse endometrium. Therefore, mid-term chronic E2-treatment might partially induce glandular cell transformation of uterine endometrium via overexpression of Fos/Jun.

Animals↗

Rare occurrence of p53 and ras gene mutations in preneoplastic and neoplastic mouse endometrial lesions induced by N-methyl-N-nitrosourea and 17 beta-estradiol.

To examine K-, H-, or N-ras and p53 gene mutations in mouse endometrial carcinogenesis induced by N-methyl-N-nitrosourea and 17 beta-estradiol, we performed polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) in 13 adenocarcinomas and 11 other preneoplastic lesions. A significant shifted band in exon 5 of p53 using PCR-SSCP was detected in one of 13 adenocarcinomas. Direct sequencing showed that the mutation was TCA-to-TGA (Ser-to-End) transition. These results suggest that ras gene mutations were not related to carcinogenesis and inactivation of p53 may occur with low frequency during the mouse endometrial carcinogenesis in this model.

Adenocarcinoma↗

Epidermal growth factor stimulates hydrolysis of phosphatidylinositol 4,5-bisphosphate, generation of diacylglycerol and exocytosis in mouse spermatozoa.

Mouse spermatozoa stimulated with epidermal growth factor (EGF) or zona pellucida (ZP) experienced phosphatidylinositol 4,5-bisphosphate hydrolysis, diacylglycerol (DAG) generation and acrosomal exocytosis. The agonists showed additive effects but the action of EGF is likely to be mediated by a distinct receptor because maximal stimulation achieved with EGF was enhanced further by ZP. Generation of DAG and exocytosis stimulated by EGF were inhibited by tyrphostin A48, indicating that tyrosine kinase activity mediates EGF action. On the other hand, pertussis toxin did not affect the EGF-induced formation of DAG or exocytosis, ruling out the involvement of sperm Gi-like proteins. These results indicate that EGF could be an important co-factor in the initiation of exocytosis in spermatozoa.

Acrosome↗

The expression of pituitary adenylate cyclase-activating polypeptide (PACAP) mRNA in rat brain: possible role of endogenous PACAP in vasopressin release.

We investigated the expression of pituitary adenylate cyclase-activating polypeptide (PACAP) mRNA in rat brain by in situ hybridization. PACAP mRNA was prominently expressed in arcuate nucleus (ARC). Three days of water deprivation significantly increased plasma arginine vasopressin and markedly potentiated the expression of PACAP mRNA in ARC. These results suggest that PACAP in ARC may play some physiological role, possibly one of which may be the control of vasopressin release.

Animals↗

Successful pregnancy in a patient with pseudomyxoma peritonei arising from ovarian mucinous cystadenocarcinoma treated with cisplatin.

A 24-year-old Japanese woman clinically showing pseudomyxoma peritonei arising from ovarian mucinous cystadenocarcinoma FIGO stage Ic is reported. She received intra-abdominal administrations of cisplatin five times following left oophorectomy. After being free of disease for 6 months, she conceived and carried two pregnancies to successful deliveries at 34 and 37 weeks, respectively. At the Cesarean sections, there were no abnormal findings except for right ovarian mucinous cystadenoma. She has had no evidence of recurrence by the time of the 60-month postoperative examination.

Abdomen↗

Evaluation of a low-dose intravesical bacillus Calmette-Guérin (Tokyo strain) therapy for superficial bladder cancer.

To examine whether intravesical instillation of low-dose bacillus Calmette-Guérin (BCG) therapy is effective with low toxicity, we reviewed data for 111 patients with superficial bladder cancer (stages Ta and T1). Among them, 74 received the BCG treatment for prophylaxis of intravesical recurrence after transurethral resection, and the remaining 37 therapeutically for Ta or T1 tumours. The patients were divided into two groups by instillation dose of BCG (Tokyo 172 strain): 40 mg (n = 55) and 80 mg (n = 56), and statistically compared for recurrence, antitumour effect and toxicity. The mean instillations were done 8.4 times in the 40 mg dose group and 8.6 times in the 80 mg dose group. Among the 74 patients with BCG therapy for prophylaxis those with a previous episode of bladder cancer treatment (n = 47) experienced a significantly (p = 0.006) shorter recurrence-free interval than those with no episode (n = 27). Among 47 patients with a previous treatment episode, those receiving the 80 mg dose demonstrated a significantly longer recurrence-free interval than those given the 40 mg dose (p = 0.03). Among the 27 patients without previous treatment no significant difference in recurrence-free intervals was found between the two dose groups. Univariate and multivariate analyses using Cox's proportional hazards model confirmed the above findings. The recurrence index was also significantly reduced after BCG therapy in the 80 mg and 40 mg groups and similar antitumour effects for Ta or T1 tumours were observed in the two dose groups. The degree of toxicity due to BCG therapy was significantly (p = 0.02) lower with the 40 mg dose. The present study suggests that (1) a 40 mg BCG low-dose (Tokyo 172 strain) regimen is useful for preventing recurrence, with sufficient therapeutic efficacy and low frequency of toxicity, among patients without a previous treatment, and (2) prophylactic effects with the 80 mg dose regimen are much superior for previous treatment cases.

Aged↗

Relationship between insulin-dependent diabetes mellitus (IDDM) and non-insulin-dependent diabetes mellitus: beta-cell function, islet cell antibody, and haptoglobin in parents of IDDM patients.

To examine the relationship between non-insulin-dependent diabetes mellitus (NIDDM) and insulin-dependent diabetes mellitus (IDDM), we studied beta-cell function, HLA type, and serologic markers of IDDM and NIDDM in the parents of IDDM patients. Fifty-two parents of 33 IDDM patients were examined in terms of islet-cell antibody (ICA) status, haptoglobin phenotype, HLA type, and insulin responses during an oral glucose tolerance test (OGTT). Twenty-seven parents were prospectively evaluated for up to 113 months. They were divided into the following three groups based on pattern of ICA positivity during the follow-up period: group 1, persistently positive ICA (n = 4); group 2, fluctuating ICA (n = 7); and group 3, persistently negative ICA (n = 16). Twenty-three percent (12 of 52) of the parents of IDDM patients had NIDDM, and 12% (six of 52) of the matched controls did. The prevalence of ICA in the parents (11 of 52, 21%) was greater than in normal controls (one of 112, P < .01). Diabetic parents tended to show a higher prevalence of ICA (six of 12, 50%) than nondiabetic parents (six of 40, 15%; P = .06). ICA-positive parents showed higher glucose levels and lower insulin responses than ICA-negative parents. Three of four parents in group 1 slowly progressed to an insulin-dependent state during 25 +/- 3 months of follow-up evaluation. Parents in group 2 and group 3 did not show any changes in glucose levels or insulin responses during the study.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗