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Biomedical subjects

F Kobayashi

Publications and source records attributed to F Kobayashi.

At least 109 records · Page 6Linked to original sources
PubMed1992

Enhanced muscle sympathetic nerve activity during sleep apnea in the elderly.

To examine how muscle sympathetic nerve activity (MSNA) becomes modified during sleep apnea in the elderly, we analyzed polysomnographic recording simultaneously with microneurographically recorded MSNA. Subjects were three healthy elderly males aged 72, 75, and 76. MSNA was suppressed with deeper non-REM sleep stages in these elderly subjects. In all three subjects, sleep apnea for 10 s or longer was observed during sleep of 00:00-06:00. During sleep apnea, MSNA was enhanced concomitantly with a blood pressure fall and a reduction in saturation rate of oxyhemoglobin. With the termination of sleep apnea, MSNA was maximally enhanced with a transient elevation of blood pressure. We conclude that sleep apnea induces an enhancement of MSNA, which may be responsible for hypertensive episodes during sleep.

Aged↗
PubMed1992

Blood pressure response to hyperinsulinemia in salt-sensitive and salt-resistant rats.

We investigated the role of insulin in salt-sensitive hypertension in Dahl salt-sensitive and salt-resistant rats. The rats were kept in metabolic cages, and sodium intake and urinary sodium excretion were measured. In salt-sensitive rats receiving a 0.3% NaCl diet, sodium retention was significantly greater at weeks 1 and 2 in rats that received an insulin infusion than in those receiving a saline infusion. Mean arterial blood pressure and plasma norepinephrine levels were significantly higher at week 3 in insulin-treated rats than in saline-treated rats (mean arterial pressure, 137 +/- 3 mm Hg versus 119 +/- 3 mm Hg, p < 0.05; plasma norepinephrine, 0.40 +/- 0.02 ng/ml versus 0.27 +/- 0.01 ng/ml, p < 0.05). Insulin did not influence sodium retention, mean arterial pressure, or plasma norepinephrine in salt-resistant rats. Coadministration of an alpha-blocker (bunazosin, 10 mg/kg per day for 3 weeks) in salt-sensitive rats abolished the insulin-induced elevations in mean arterial pressure and sodium retention. When salt-sensitive rats were fed a low salt diet (0.03% NaCl), insulin did not raise mean arterial pressure. Thus, insulin elevated blood pressure only in the salt-sensitive model. The sympathetic nervous system and sodium retention in the early phase of insulin overload may contribute to elevation of mean arterial pressure in this model.

Animals↗
PubMed1992

[Clinical significance of serum CA130 level in women with spontaneous abortion, hydatidiform mole and early normal and tubal pregnancy].

We examined the serum CA130 level in women in early pregnancy with normal (n = 13), and abnormal (n = 28) course. The abnormal course consisted of intrauterine spontaneous abortion (n = 10), hydatidiform mole (n = 3) and tubal pregnancy (n = 15). The serum CA130 level was higher than for normal nonpregnant women (35u/ml) in 69% (9/13) of women with normal pregnancy, 90% (9/10) of those with intrauterine spontaneous abortion and 100% (3/3) of those with hydatidiform mole; the mean value and standard deviation for these three groups were 131 +/- 150u/ml (n = 13), 197 +/- 253u/ml (n = 10), and 47 +/- 15u/ml (n = 3), respectively. In contrast, the serum CA130 level of the 15 women with tubal pregnancy was 28 +/- 21u/ml. Among these patients, all of the 13 women without genital bleeding had a CA130 level within the normal range for nonpregnant women (mean +/- SD; 20 +/- 6u/ml). Since CA130 is abundant in the decidual tissue but is scant in tubal tissue, a high CA130 level in maternal sera during early pregnancy may indicate the presence of the destruction of decidual tissue, while a low or normal CA130 level throughout early pregnancy is regarded as characteristic of tubal pregnancy.

Abortion, Spontaneous↗
PubMed1991

Lack of correlation between the amount of eugenol released from zinc oxide-eugenol sealer and cytotoxicity of the sealer.

The purpose of this study was to examine a possible correlation between the eugenol released from a zinc oxide-eugenol sealer (Canals) and the degree of cytotoxicity. The cytotoxicity and eugenol release from root canal filling material containing eugenol was examined for test solutions at several experimental periods. No positive correlation was found between eugenol release and cytotoxicity of the root canal filling material.

Animals↗
PubMed1991

Age-related changes of sympathetic outflow to muscles in humans.

Muscle sympathetic nerve activity (MSA) was recorded microneurographically from the tibial nerve in 40 healthy male subjects aged 18 to 75. Passive and graded head-up tiltings were loaded on the subjects. The effects of aging on the resting activity of muscle sympathetic nerve in supine position at rest (burst number per minute), increase in MSA from the resting level by orthostasis (slope of the regression line between sine of the tilt angle and MSA bursts per minute), and the MSA in upright standing position were analyzed. The resting MSA increased with age, and a significant positive correlation was observed between age and resting activity (Y = -6.83 +/- 0.876X, r = .882, p less than .001). The MSA was enhanced by head-up tilt linearly with the sine of the tilt angle, and a significant negative correlation was observed between age and the MSA increase by orthostasis (Y = 57.6 - 0.582X, r = . 843, p less than .001). Standing MSA increased significantly but less remarkably than resting MSA. It was concluded that aging increases the resting activity, but there is less increase in the standing activity of sympathetic outflow to muscles in humans.

Adolescent↗
PubMed1991

Serial changes of serum CA125 levels during menstrual cycles.

Serial changes of serum CA125 levels during 32 menstrual cycles were examined in 32 healthy young women (19-21 years of age) charting basal body temperature (BBT) and measuring serum estradiol and progesterone levels. Analysis of BBT charts and serum progesterone levels revealed that the 32 menstrual cycles could be classified into either an ovulatory cycle with a sustained BBT temperature increase for at least 10 days (type I: 9 cycles), an ovulatory cycle with a sustained BBT temperature increase for less than 10 days (type II: 17 cycles), or anovulation (type III: 6 cycles). All 32 cycles exhibited basal CA125 levels of less than 35 u/ml throughout the cycle, except during the period of menstruation. At menstruation, 7 of the 9 cycles of type I showed a marked, transient elevation of CA125 levels from previous basal levels (a mean net increase). On the other hand, 12 of 17 cycles of type II showed only a slight elevation of CA125 levels during the period of menstruation. None of the 6 cycles of type III showed any apparent increase in CA125 levels during the period of menstruation. The mean net increase of CA125 levels during the period of menstruation in the cycles of type I was significantly higher than that of the cycles of type II (p less than 0.05) and type III (p less than 0.05). These results imply that a transient elevation of serum CA125 levels during the period of menstruation occurs in cycles with ovulation, and the levels of elevation seem to be closely associated with the duration of the sustained BBT temperature increase.

Adult↗
PubMed1991

Role of sympathetic activity in blood pressure reduction with low calorie regimen.

To investigate the effects of a low calorie regimen on sympathetic function and its relation to blood pressure response, 22 untreated obese essential hypertensive patients (50 +/- 2 years, body mass index 29 +/- 1 kg/m2) were hospitalized and a diet was prescribed of 2,000 kcal/day for 5 days (control period) followed by 800 kcal/day for 21 days without changing salt intake (8-10 g/day). The dose of intravenous phenylephrine infusion needed to elevate systolic blood pressure 20 mm Hg (CD20) and the 24-hour urinary excretion of norepinephrine (UNE) were measured. During the low calorie period, blood pressure normalized in 14 patients (responder group, 124 +/- 3/79 +/- 4 mm Hg) and eight remained hypertensive (poor responder group, 158 +/- 6/103 +/- 3 mm Hg). At the control period, blood pressure and body mass index were similar, but the responder group had higher UNE (134 +/- 15 micrograms/day) and CD20 (127 +/- 11 micrograms) than the poor responder group (89 +/- 6 micrograms/day and 79 +/- 13 micrograms, respectively). During the low calorie period, both UNE (87 +/- 15 micrograms/day) and CD20 (74 +/- 10 micrograms) decreased in the responder group; no change was seen in the poor responder group. Changes in UNE and systolic blood pressure were correlated (r = 0.6, p less than 0.05). In conclusion, suppression of sympathetic activity plays a role in blood pressure reduction during moderate caloric restriction.

Blood Pressure↗
PubMed1991

Hematological studies on naturally occurring substances. VI. Effects of an animal crude drug "chan su" (bufonis venenum) on blood coagulation, platelet aggregation, fibrinolysis system and cytotoxicity.

During the screening test of the animal crude drug "Chan su" (Chinese name, toad-cake), the venom of Bufo bufo gargorizans CANTOR (Bufonidae), on blood coagulation, platelet aggregation, fibrinolysis system and cytotoxicity, the ethyl acetate extract showed promotive action on platelet aggregation and remarkable cytotoxic activity on HeLa-S3 cells. Nine kinds of bufadienolides were isolated from the ethyl acetate extract by bioactivity-guided fractionation and were identified by chemical and spectral analysis.

Animals↗
PubMed1990

Skin sympathetic activity in the tibial nerve triggered by vibration applied to the hand.

The effect of vibration applied to the hand on skin sympathetic activity (SSA) in the lower limbs was studied in five healthy subjects. SSA from the right tibial nerve at the popliteal fossa, plethysmogram from the right index toe and perspiration from the sole of the right foot were measured when vibration of 100 m/s2 at 60 Hz was applied to the left palm for 1 min. The SSA response to vibration exposure differed among subjects, but every subject showed an increase in SSA from the tibial nerve when vibration was applied to the hand. Decrease in amplitude of plethysmogram from the toe was also found in all subjects. One subject displayed a remarkable increase in perspiration on the sole of the foot together with a great increase in SSA. The present findings indicated that even vibration exposure of the hand triggers sympathetic activity in the tibial nerve innervating the foot, and causes vasoconstriction of the toe and perspiration on the sole of the foot.

Adult↗
PubMed1990

Immunohistochemical localization of CA130 in fetal tissues, and in normal and neoplastic tissues of the female genital tract.

A murine monoclonal antibody, 130-22, produced against a human lung adenocarcinoma cell line (PC-9) has been suggested as recognizing an antigenic determinant (CA130) which is different from an epitope recognized by OC125 on CA125 glycoprotein molecules. The immunohistochemical reactivity with the 130-22 antibody (anti-CA130) was examined in human fetal tissues, and normal and neoplastic tissues of female genital tracts, and compared to those using OC125. Among the fetal tissues, the amnion and the cells of coelomic epithelium and mullerian-derived epithelia reacted with anti-CA130. In normal adult tissues, cervical and endometrial gland cells, tubal epithelial cells, and ovarian surface cells reacted with anti-CA130. In addition, predecidual cells in the late secretory endometrium and decidual cells during gestation were positive. Among the neoplastic tissues, tubal and endometrial adenocarcinomas and epithelial ovarian tumors were positive for anti-CA130. There were no differences in the respective specimens between the immunohistochemical localization of anti-CA130 and of OC125. Therefore, anti-CA130 is considered to be useful in the immunohistochemical detection of CA125 glycoprotein molecules as well as OC125.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1990

[Bone mineral contents of lumbar vertebrae in postmenopausal women--using a quantitative computed-tomography method].

We measured bone mineral contents of lumbar vertebrae (L1, L2, L3, L4) in 58 post-menopausal female volunteers (49-76 years old), using a quantitative computed-tomography method. We investigated age-related changes of bone mineral content, and analyzed the relation of bone mineral content to vertebral deformity and to physical characteristics. The following results were obtained: (1) There were highly significant correlations and some significant differences among bone mineral contents of L1, L2, L3 and L4. (2) Bone mineral content showed an apparently linear decline with age. (3) A significant negative correlation was observed between bone mineral content and the central deformity index of the vertebral body, but not for the anterio-posterior deformity index. (4) It was difficult to verify an association of bone mineral content with physical characteristics, such as height, weight, and body mass index.

Aged↗
PubMed1990

Possibility for induction of convulsion by fleroxacin and its disposition in the central nervous system in animals.

Fleroxacin and its metabolites were examined for their possibility of the induction of convulsion in mice, inhibitory activity on GABA receptor binding, and disposition in the central nervous system of mice, rats and dogs. No convulsion was evoked in mice at high oral combination doses of fleroxacin and fenbufen. Brain-to-serum concentration ratios of fleroxacin after oral dose were 0.13 in mice, 0.19 in rats and 0.28 in dogs. Rats showed no accumulation of fleroxacin in brain and similar elimination from brain to that from serum after the oral dose. Dogs exhibited the similar distribution of fleroxacin into various brain regions. The inhibitory effect of fleroxacin on GABA receptor binding was relatively weak and slightly potentiated in the presence of 4-biphenylacetic acid. Demethyl fleroxacin showed more potent inhibitory activity on GABA receptor binding and potentiation with 4-biphenylacetic acid. The combination of intravenous demethyl fleroxacin and oral fenbufen showed no convulsion in mice. Fleroxacin N-oxide showed only slight inhibitory activity on GABA receptor binding, being not influenced with 4-biphenylacetic acid.

Animals↗
PubMed1990

[Levels of CA130 in maternal sera and amniotic fluid at various gestational ages].

We examined the CA130 concentration in the amniotic fluid, maternal sera, amnion, chorion, decidua and placenta. CA130 in the maternal sera showed an initial increase during early pregnancy, remained low from the 15th weeks of pregnancy until delivery, and then increased after term delivery (249u/ml, mean, n = 27) or mid-trimester abortions (844u/ml, n = 22). The CA130, concentration in the amniotic fluid was high in the mid-trimester and remarkably low at term. Among the tissues examined, amnion and decidua contained a relatively high concentration of CA130. Immunohistochemical examination also demonstrated abundant CA130 in the cytosol of amnion and decidua tissues. The pattern of changes in CA130 in amniotic fluid was similar to that in the amnion and decidua tissue. The results suggest that the amnion cells are the source of CA130 in the amniotic fluid and that the high concentration of CA130 in maternal serum after delivery originates in decidua tissue affected by the separation of the placenta.

Amnion↗
PubMed1990

[Comparison of cardiac output between in DDD and in VVI by pulsed Doppler echocardiographic method (correction with Swan-Ganz catheter method)].

Difference of cardiac output and stroke volume between that in DDD and that in VVI was studied by pulsed Doppler echocardiography at different pacing rates. Moreover, to evaluate the usefulness of the method by pulsed Doppler echocardiography, cardiac output by the Swan-Ganz catheter method was measured and compared. Fourteen patients age 37-83 years (mean 65 years) with sick sinus syndrome and implanted multiprogrammable dual chamber pacemakers were studied. Cardiac output was measured as the product of the echocardiographically determined cross sectional area of the aortic anulus and the Doppler-determined mean velocity of left ventricular outflow over systole. Cardiac output was greater in DDD with atrial kick than in VVI at each pacing rate, and increased with elevation of the rate, but it was smaller at 120 PPM than at 110 PPM in DDD. Stroke volume was greater in DDD than in VVI at each pacing rate, and maximum volume was at 60 PPM in both modes. The data by pulsed Doppler echocardiography and by Swan-Ganz catheter method have high correlation. Besides being related with pulse rate, these results may be related with such things as myocardial contractility, preload and afterload. For example, the tension of autonomic nervous system, the changing of venous return volume, the disease of arteriosclerosis and old myocardial infarction, temperature, blood viscosity and so on. We will continue the study considering these factors.

Adult↗