Biomedical subjects

N Satoh

Publications and source records attributed to N Satoh.

At least 235 records · Page 13Linked to original sources

PubMed1992

Determination of free N-acetylamino acids in biological samples and N-terminal acetylamino acids of proteins.

N-Acetylamino acids were derivatized with 9-anthryldiazomethane to the corresponding esters. The anthryl esters were separated by high-performance liquid chromatography and detected fluorimetrically (excitation at 365 nm; fluorescence emission measured at 412 nm). N-Acetyl derivatives of Asn, Gln, Ser, Thr, Gly, Ala, Tyr, Pro, Met, Val, Ile and Leu as well as N-formyl-Met could be separated and identified in the same chromatographic run. The detection limit was from 0.10 pmol for AcGln to 5.5 pmol for AcIle and AcLeu. When the acetylamino acids listed above were added to the 700 g supernatant of a rat liver homogenate, the mean recovery was 72%. AcAla and AcTyr were found in free form in baker's yeast. Proteins with an acetylated N-terminus were digested by a protease, and the peptides formed were treated with an N-acylamino acid-releasing enzyme. This method was applied to end-group determination of four proteins (each 0.5 nmol).

Acetamides↗

PubMed1992

[Study on uric acid metabolism in patients with primary aldosteronism].

This study was conducted to elucidate renal uric acid metabolism in patients with primary aldosteronism (PA;16 cases) as compared with normotensive subjects (NT;25 cases) and essential hypertensives (EHT;51 cases). All subjects were hospitalized and received a regular diet(Na;120 mEq,K;75 mEq,daily) for more than two weeks, after which renal clearance tests were performed, and serum uric acid(SUA), fractional excretions of uric acid(FEUA), sodium(FENa), and inorganic phosphorus(FEP) were evaluated. Plasma aldosterone concentration(PAC) was measured in 16 patients with PA before treatment and in 8 patients after adrenalectomy. SUA was lower in PA than in either NT or EHT, and this lowering was more obvious in male subjects. In NT, PA and EHT, FEUA, an index of renal excretion of uric acid, correlated negatively with SUA and positively with FENa and FEP, which reflected sodium reabsorption at the renal total tubules and proximal tubules, respectively. Although FENa was nearly the same in all the three groups, FEUA and FEP were significantly higher in PA than in EHT or NT. However, no significant correlation was found between PAC and SUA or FEUA in PA. In PA a significant increase of SUA, and decreases of FEUA and FEP were observed after the removal of adenoma compared to before the surgery. These results suggest that uric acid transport might be closely related to sodium transport in the renal tubules, particularly at the proximal site, and also lead to the conclusion that the lower SUA in PA resulted from the suppression of reabsorption and/or an enhancement of secretion of uric acid in the proximal tubules, being related to the so-called escape phenomenon.

Adenoma↗

PubMed1992

Demyelinating peripheral neuropathy in Cockayne syndrome: a histopathologic and morphometric study.

The clinical and histopathological features of Cockayne syndrome in a 2-year-old girl are reported. Sural nerve biopsy revealed segmental demyelination and remyelination. The density of myelinated fibers, especially small ones, was decreased in comparison with an age-matched control. Although the total number of unmyelinated fibers showed no difference from that in the control, the number of small unmyelinated fibers was slightly increased. A study of teased fibers from the patient's nerve revealed that 1% of the fibers had segmental demyelination, and 7% showed remyelination. Ultrastructurally, demyelinated fibers were present sporadically. No degeneration of axons was evident. Our pathological and morphometric data for the sural nerve suggest the presence of primary demyelination in early childhood.

Child, Preschool↗

PubMed1992

Case report: alternation therapy with antileukemic agents and recombinant human granulocyte colony-stimulating factor for RAEB in transformation.

Under the assumption that in some patients with refractory anemia with excess of blasts (RAEB), the abnormal clones might be less responsive to granulocyte colony-stimulating factor than normal clones, the authors tried alternation therapy with a recombinant form of this factor (rhG-CSF) and antileukemic agents in the treatment of two patients with RAEB in transformation. After repetition of the short-cycled alternation therapy, the hematologic findings of both patients were completely normalized and have remained so without any adverse side effects under the continuation of this therapy for more than 5 months. Judging from our clinical experience, the alternation therapy may be a new efficient therapeutic strategy for RAEB and some types of slowly progressive leukemia.

Adult↗

PubMed1992

Reaction of sevoflurane and its degradation products with soda lime. Toxicity of the byproducts.

Sevoflurane previously has been reported to undergo extensive degradation in the presence of soda lime. To more completely characterize the extent and significnce of this reaction, we studied degradation of sevoflurane with and without soda lime, as well as the toxicity and mutagenicity of the degradation products. Two degradation products detected were CF2 = C(CF3)OCH2F (compound A) and CH3OCF2CH(CF3)OCH2F (compound B). During circulation of 1%, 2%, and 3% sevoflurance in a closed anesthesia circuit for 8 h, peak concentrations of compound A were 13.3 +/- 0.27, 30.2 +/- 0.10, and 42.1 +/- 1.07 ppm at 2 h, respectively. The concentrations of compound B did not exceed 2 ppm. The temperature of the soda lime was 43.3 +/- 2.8 degrees C at 1 h and increased gradually to 47.9 +/- 1.5 degrees C after 8 h. In closed flasks with soda lime, the magnitude of the decrease in sevoflurance concentrations (3%) and of the increase in compound A concentrations was temperature dependent. The peak concentrations of compound A at 23 degrees C, 37 degrees C, and 54 degrees C were 32.8 +/- 6.8 at 2 h, 46.6 +/- 1.0 at 0.5 h, and 78.5 +/- 2.3 ppm at 0.5 h, respectively. The LC50 (50% lethal concentration) of compound A in Wistar rats was 1,090 ppm in males and 1,050 ppm in females exposed for 1 h. The LC50 was 420 ppm in males and 400 ppm in females exposed for 3 h. The chronic toxicity of compound A in Wistar rats was studied by exposing rats 24 times, for 3 h each, to initial concentrations of 30, 60, or 120 ppm in a ventilated chamber. At all concentrations, there were no apparent effects other than a loss of body weight in females (120 ppm) on the final day (P < 0.01). Compound A did not induce mutation on the reverse (Ames) test at less than 2,500 micrograms/dish (culture medium 2.7 ml) with activation by S-9 mixture, and below 1,250 micrograms/dish (culture medium 2.7 ml) without activation, in four strains of S. typhimurium and in 1 strain of E. coli. Exposure of fibroblasts to 7,500 ppm of compound A for 1 h, compound A did not induce structural change. In a study of acute toxicity of compound B, there was no toxicity in Wistar rats after 3 h of exposure at 2,400 ppm. The reverse (Ames) test for compound B was negative at 625-1,250 micrograms/dish.(ABSTRACT TRUNCATED AT 400 WORDS)

Absorption↗

PubMed1992

Effects of SUN-1165, N-(2,6-dimethylphenyl)-8-pyrrolizidine acetamide hydrochloride hemihydrate, a new class I antiarrhythmic drug, on ventricular arrhythmias, intraventricular conduction, and the refractory period in canine myocardial infarction.

Effects of SUN-1165, a class I antiarrhythmic drug, on ventricular arrhythmias, intraventricular conduction, and the effective refractory period (ERP) were examined in a canine model of myocardial infarction and compared with those of lidocaine. The antiarrhythmic effects were examined on the arrhythmias developed 24 h after left anterior descending coronary artery (LAD) ligation and ventricular premature stimulation-induced arrhythmias 5-7 days after LAD ligation. Effects on intraventricular conduction and ERP were also examined in animals 5-7 days after LAD ligation. The intraventricular conduction time (CT) was determined by excitation induced by a ventricular stimulation at various coupling intervals from 200 to 1,000 ms. SUN-1165 (1 and 3 mg/kg) showed a marked reduction in the frequency of ventricular ectopic beats 24 h after LAD ligation and was more potent than lidocaine. SUN-1165 (1 and 3 mg/kg) prolonged CT in the infarcted zones over a wide range of the coupling intervals and produced block of severely delayed conduction. In contrast, lidocaine prolonged CT only at short coupling intervals. Ventricular premature stimulation produced ventricular arrhythmias, which were prevented by pretreatment with SUN-1165 (3 mg/kg). ERP was prolonged by SUN-1165 (3 mg/kg). In conclusion, SUN-1165 showed antiarrhythmic effects in a canine model of myocardial infarction. A selective depression of delayed conduction in the infarcted zone and a prolongation of ERP probably contribute to this antiarrhythmic effect.

Animals↗

PubMed1992

Expression and purification of recombinant 3C proteinase of Coxsackievirus B3.

We have cloned various lengths of coxsackievirus B3 cDNA encompassing the region encoding the 3C proteinase, which is essential to the viral replication cycle. Such viral cDNAs were fused in frame to the 5'terminal portion of the lacZ' gene carried on the vector pUC118 to express mature 3C proteinase in Escherichia coli. In the E. coli cells containing pCXB108 or pCXB117, constructed for this study, a large amount of 23-kDa protein was synthesized in the presence of IPTG. This protein was purified and was shown to be intact 3C proteinase. These data suggest that 3C proteinase, expressed as a part of a fusion protein, was active in E. coli and released itself from the precursor fusion protein by autocatalytic cleavage.

3C Viral Proteases↗

PubMed1992

A comparative study of dynamic CT and ultrasonic pulsed Doppler method for estimation of the portal blood flow.

A new dynamic CT method for evaluating the portal blood flow is described. Thirty healthy volunteers were injected with non-ionic hypo-osmotic iodine contrast medium to estimate the portal blood flow. Time density curves (TD-curves) for the abdominal aorta and the main trunk of the portal vein were determined on the basis of data obtained by dynamic CT. From the TD-curves, portal blood flow coefficient and circulation time to flow into the portal vein (P-P time) were calculated. More detailed data of the TD-curves could be obtained by the new dynamic CT than by the previous methods. Subjects were simultaneously studied by an ultrasonic pulsed Doppler method which has been clinically accepted. There was a significant correlation between our dynamic CT method (portal blood flow coefficient) and the ultrasonic pulsed Doppler method concerning the measurement of portal blood flow. Therefore, it may be concluded that this CT method is reliable and clinically acceptable.

Adult↗

PubMed1992

[A case of systemic lupus erythematosus complicated with monoclonal CD5 + B cell proliferation suspected as chronic lymphocytic leukemia].

A case of systemic lupus erythematosus (SLE) complicated with monoclonal CD5 + B cell proliferation in peripheral blood and bone marrow is reported. A 59-year-old man suffering from left chest pain was admitted to the hospital because of thrombocytopenia (platelets 1.9 x 10(4)/mm3). The diagnosis of SLE was made from (1) pleuritis (2) autoimmune thrombocytopenia (3) positive anti-DNA antibodies, positive LE cell preparation (4) positive antinuclear antibodies. Prednisolone 60mg per day was started. From that time monoclonal CD5 + B cells began to increase in peripheral blood (maximum lymphocyte counts 11000/mm3, CD5 + B cells 77.6%) and bone marrow, and the complication of chronic lymphocytic leukemia (CLL) was suspected. It is said that patients of CLL often have various autoantibodies, and in about 15% of CLL patients complicate autoimmune hemolytic anemia, but those who develop collagen diseases are rare. And while lymphoid malignancies occur more often in the patients of SLE in comparison with normal subjects, the reports of the patients who complicate the proliferation of monoclonal CD5 + B cells like CLL are very few. But from many facts that indicate the relation between CD5 + B cell or its proliferation and the production of autoantibodies or autoimmune diseases, we consider this case worth to be reported.

Antigens, CD↗

PubMed1992

Isolated post exercise delayed ST depression as a sign of severe ischemia: the influence of percutaneous transluminal coronary angioplasty.

The clinical implications of isolated late recovery ST depression were tested in patients with scintigraphically defined ischemia (coronary artery disease [CAD], n = 18) compared with patients without ischemia (n = 25). Spontaneous (78.4 versus 12.0%, P < 0.008) and exercise-induced angina (44.4 versus 0%, P < 0.0001) were more frequently seen in patients with CAD. Histories of unstable angina (33.3%), prior myocardial infarction (27.8%), ST elevated angina (22.2%) and significant stenosis in the left anterior descending artery (17 of 18, 94.4%) were almost exclusively seen in the CAD group. There was no significant difference between the two groups in capacity for exercise, maximum deviation of ST level or TV2 amplitude. Balloon angioplasty abolished late recovery ST changes in 63.6% of CAD patients. These results suggest that isolated late recovery ST depression, when accompanied with typical chest pain, may be considered as an indicator of myocardial ischemia, but this phenomenon is difficult to distinguish electrocardiographically.

Adult↗

PubMed1992

[Tuberculosis in young generation: a report from six general hospitals].

We investigated epidemiologic and clinical aspects of tuberculosis in young generation and pointed out problems in ambulatory treatment. In six general hospitals in Tokyo, 418 cases of tuberculosis (285 males and 133 females) were diagnosed between 1983 and 1991. They were divided into three groups; 1) young group, 10 to 29 yr (62 cases), 2) middle age group, 30 to 69 yr (255 cases), 3) elderly group, above 70 yr (101 cases). And the risk of clinical breakdown, method of case finding, radiological findings, extra-pulmonary lesions, method of diagnosis, relationship with epidemics, patient's delay, doctor's delay, drug regimens and patient's compliance in each group were investigated. In addition, after completion of therapy we sent them survey questions about relapse and attack of tuberculosis among their families. Results were followings. 1) Estimated risk of clinical breakdown by age was calculated as follows, (the number of patients)/(the population of Tokyo)/(estimated incidence of infection). This was extremely high in young group. 2) Sixteen percent of patients in young group were related with epidemics and another eight percent with familial outbreaks. 3) Although many patients in young group showed focal lesions in chest radiographies, the rate of symptomatic patients was 61% and that was almost same as in other groups. 4) The rate of patients showing atypical radiographic findings, extra-thoracic lymphadenopathy and idiopathic pleuritis were relatively high in young and elderly group. 5) Results of survey questions showed no relapse among ambulatory treated patients. Familial outbreaks (three cases) were thought to be caused by long patient's delay and not by ambulatory treatment of smear-positive patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1992

[The study of pulmonary tuberculosis in the elderly].

A clinical study of 52 patients diagnosed as having pulmonary tuberculosis at National Chiba-Higashi Hospital between 1988 and 1990 was performed. The cases ranged in age from 80-89 years; mean male patient age was 82.5, and mean female patient age was 84.3. Diagnosis of the cases were as follows: 19 discovered when checking into hospital because of chest symptoms; 14 diagnosed during the treatment of other diseases; 14 diagnosed during admission to the hospital for other diseases; and five cases were detected by chest X-rays. A total of 38 cases, had received primary treatment for pulmonary tuberculosis, 11 cases had received secondary treatment, and three cases were receiving treatment for tuberculosis. Upon admission to the hospital after the detection of tuberculosis, 19 cases tested positive to sputum smear examinations, six cases tested positive to culture examinations but negative to smear examinations, and culture examinations were negative in 27 cases. Regarding the chest X-ray findings, using the criterion of roentgenological classification for pulmonary tuberculosis established by the Japanese Society for Tuberculosis, two cases revealed type I, 29 cases revealed type II, and 21 cases revealed type III. Cavitary cases were observed in 60% of the chest X-ray findings. Upon hospital admission, 18 cases were observed to have circulatory diseases, 16 cases had central nervous diseases, 12 cases had digestive diseases and 11 cases had respiratory diseases. Nine cases had malignant neoplasm, five cases had diabetes mellitus and 14 cases had other diseases. A total of 18 cases ended in death; six cases died of pulmonary tuberculosis, and 12 cases died of other diseases.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1992

[Effects of intravenously infused magnesium on renal calcium metabolism and plasma parathyroid hormone in patients with essential hypertension].

This study aimed to elucidate the effects of intravenously infused magnesium on renal calcium and sodium metabolism in patients with essential hypertension. Mean arterial pressure (MAP), heart rate (HR), urine volume (UV), endogenous creatinine clearance (Ccr), urinary excretion of calcium (UCaV) and sodium (UNaV), fractional excretion of calcium (FECa) and sodium (FENa), plasma ionized calcium (pCa2+) and parathyroid hormone(PTH) were measured before and after intravenous infusion of 10% magnesium sulfate (initial dose: Mg 13.5mg/m2.BSA/15 min.: maintenance dose: Mg 2.7mg/m2.BSA/105min) in 6 normotensive subjects (NT) and 13 mild-to-moderate essential hypertensives (EHT). After the magnesium infusion, significant increases of UV, UCaV, UNaV, FECa and FENa, and a significant decrease of PTH were observed in both NT and EHT while MAP and HR did not change in either group. PCa2+ significantly decreased and Ccr tended to increase only in EHT. Although no significant difference was found in the change in Ccr (delta Ccr) or PTH (delta PTH) between NT and EHT, the changes of UCaV (delta UCaV), UNaV (delta UNaV), FECa (delta FECa) and FENa (delta FENa) were greater in EHT than each in NT. A positive correlation was found between delta UCaV and delta FECa, as well as delta UCaV and delta Ccr, but the former was more remarkable in both groups. In addition, delta UCaV was positively correlated with delta FENa in EHT, but not in NT. No significant relationship was observed between delta UCaV and delta PTH in either group.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcium↗

PubMed1992

[A study of auditory screening in infant by evoked otoacoustic emission (EOAE)].

The EOAE measuring system was newly developed for infants and the clinical study of the auditory screening for large number of infants using this system was reported. The EOAE measuring system for adults was adjusted as the system for infants. The more compact recording probe than that for adults was prepared. The noise of breathing sound and body movement were rejected during measurements by the artifact rejection system of the signal processor. ABR and EOAE were measured in 166 ears of 85 infants suspected of hearing loss ranging in age between 5 days and 5 years. Twenty-nine infants' EOAEs were measured under awaking. 1.5kHz short tone bursts (35dBnHL and -10dBnHL) was used for stimulating sound in EOAE measuring, and the 100-300 epochs were averaged. The positive response in EOAE was judged by the presence of the obvious peak in 8-10ms after stimulation and confirmation of the reproducibility of this response. The responses evoked by the two different stimulations were also compared for accurate judgement. Ninty-five ears with hearing loss over 35dB in ABR were detected no responses in EOAEs on 35dBnHL stimulation. Fifty-nine ears judged as normal hearing within 30dB in ABR showed good responses in EOAEs, but 6 ears judged as normal hearing in ABR were detected no responses in EOAEs, but 6 ears judged as normal hearing in ABR were detected no responses in EOAE. The latter 6 ears were suspected of secretory otitis media in following examinations. Three cases with abnormal waveforms judged as "unevaluable" in ABR showed good responses in EOAEs indicating their normal cochlear functions. EOAE measurement in infants was easy, speedy and noninvasive. Moreover, the response of EOAEs was clearly obtained with accuracy. Considering these facts, EOAE is suitable examination for detection of hearing impairment and is a useful auditory screening in infants.

Acoustic Stimulation↗

PubMed1992

[Pulmonary tuberculosis in youth].

The study of the group younger than 29 years of age with pulmonary tuberculosis was carried out. Thirty seven out of 287 tuberculosis patients who were discharged from National Chiba-Higashi Hospital in 1989 were enrolled. Only 5 patients (13.5%) were associated with complication. The smear and culture of sputum for acid-fast bacilli were positive in 30 cases (81.1%) and chest X-ray films revealed cavitary lesion in 31 cases (83.3%). Many of them were moderately advanced cases. Twenty four of them were found symptomatically, 10 by mass survey and 3 under treatment of other diseases. The total delay of symptomatic patients was 8.5 weeks until 80% of them were definitely diagnosed. The days of hospital stay were 122 until half patients were discharged. Five of them (13.5%) were non-Japanese and all stayed in Japan illegally. Their condition was rather severe.

Adolescent↗

PubMed1991

[Evaluation of renal function by dynamic CT].

Dynamic CT scans of the kidney were conducted in 57 persons with varied renal function. The results of dynamic CT were used to obtain time-density curves for renal cortex, medulla and aorta. Various parameters were calculated from these time-density curves. Among them, CA ratio, the ratio of the area under the renal cortex curve to the area under the aortic curve, showed the best correlation with creatinine clearance. With these parameters, dynamic CT studies are believed to be useful in evaluating renal function.

Adult↗

PubMed1991

[The role of the renal dopaminergic and the prostaglandin systems in renal uric acid metabolism in patients with essential hypertension].

The present study aimed to elucidate the role of renal dopaminergic and prostaglandin (PG) systems in renal uric acid metabolism in essential hypertension. Mean arterial pressure (MAP), heart rate (HR), endogenous creatinine clearance (Ccr), serum uric acid (SUA), urinary excretions of uric acid (UUAV) and sodium (UNaV), fractional excretions of uric acid (FEUA) and sodium (FENa), plasma renin activity (PRA) and plasma aldosterone concentration (PAC) were measured before and after intravenous injection of a dopamine receptor antagonist, metoclopramide (MCP: 8 mg/m2.BSA), or before and after a single oral administration of prostaglandin synthesis inhibitor, indomethacin (IM: 75 mg), in 34 mild-to-moderate essential hypertensives (EHT). MCP injection or acute oral administration of IM caused significant decreases of UNaV and FENa in each group, whereas MAP, HR and SUA did not change in either group. Significant decreases in Ccr, UUAV and FEUA and increases in PRA and PAC were demonstrated by MCP injection, while no significant changes in these parameters were revealed by IM administration. There was a significant positive correlation between delta UUAV and delta Ccr or delta FEUA in both groups. In addition, a close positive correlation between delta UUAV and delta UNaV as well as between delta FEUA and delta FENa was found in the MCP group, but not in the IM group. On the other hand, no significant correlation was observed between delta UUAV and delta PRA or delta PAC in either MCP or IM administration. The decreases of UUAV and FEUA were significantly greater in MCP than in IM administration, despite similar changes in Ccr, UNaV and FENa between the two procedures. These data suggest that the endogenous renal dopaminergic system may contribute to renal uric acid metabolism, which is rather closely related to sodium handling in essential hypertension than the prostaglandin system. Furthermore, the attenuated renal dopaminergic activity may contribute to the elevation of serum uric acid level in patients with essential hypertension.

Adult↗

PubMed1991

[The role of hyperinsulinemia on the renal mechanism of hyperuricemia in overweight patients with essential hypertension].

The aim of the present study was to investigate the role of insulin on the renal mechanism of hyperuricemia in overweight patients with essential hypertension. Thirty-four essential hypertensives(EHT), receiving a regular diet containing 120mEq of sodium, 75mEq of potassium and 2000 kilocalories daily, were divided into two groups of non-obese(NHT) and obese(OHT) EHT. NHT as categorized as a body mass index (BMI) less than, and OHT as a BMI equal to or more than, 25 kg/m2 in male patients and 24 kg/m2 in female patients. In the early morning after overnight fast, renal uric acid and sodium clearance were examined while the patients remained in a supine position. During the two-hour clearance period, mean arterial pressure(MAP), heart rate(HR), endogenous creatinine clearance(Ccr), immunoreactive insulin(IRI), serum uric acid(SUA), fractional excretion of uric acid(FEUA) and sodium(FENa) were measured. Although there were no significant differences in age, MAP, HR, Ccr, nor SUA between the two groups, a higher ratio of female to male patients was found in OHT than in NHT. On the other hand, higher SUA and IRI and lower FEUA and FENa were observed in OHT than in sex-and Ccr-matched NHT. SUA was negatively correlated with FEUA in all patients (r = -0.392, p less than 0.05) and in NHT (r = -0.553, p less than 0.05), unlike in OHT. A significant negative correlation between BMI and FEUA was revealed in all EHT (r = -0.441, p less than 0.01) and in OHT (r = -0.597, p less than 0.01) but not in NHT. FEUA was positively correlated with FENa in all EHT (r = 0.554, p less than 0.001) as well as in NHT (r = 0.548, p less than 0.05) and OHT (r = 0.507, p less than 0.05). Moreover, there was a significant negative correlation between IRI and FENa in all EHT (r = -0.361, P less than 0.05) and in OHT (r = -0.470, p less than 0.05). However, no significant relation was demonstrated between IRI and SUA or FEUA in NHT or OHT. From these results, it is concluded that an attenuated renal excretion of uric acid related to natriuretic ability may play an important role in hyperuricemia in EHT. However, the role of hyperinsulinemia, which contributes to the blunting of natriuresis, might be relatively small in the renal mechanism of hyperuricemia in EHT, particularly in OHT.

Female↗