Search PubMed⌕ Search

Biomedical subjects

S Ando

Publications and source records attributed to S Ando.

At least 433 records · Page 24Linked to original sources

Analysis of brain lipids by high performance thin-layer chromatography and densitometry.

We have devised a high performance thin-layer chromatography (HPTLC) densitometry method to resolve the major lipid classes of brain tissue. We used DEAE-Sephadex column chromatography to separate the total lipid into neutral and acidic lipid fractions. The lipid fractions were then spotted on separate HPTLC plates and chromatographed in one dimension using two solvent systems. Quantitation was by in situ densitometry with absolute amounts of the lipid classes determined from co-chromatographed standards. An internal standard was also used to improve the precision. The individual lipid classes of rat whole brain, human brain gray and white matter, rat and bovine myelin, and bovine oligodendroglia were quantitated. Human brain phosphatidylethanolamine plasmalogen was also quantitated. Sensitivity was increased by using the cupric acetate charring reagent, which we found to be more sensitive than the conventional sulfuric acid-dichromate reagent. Total lipid (less than 400 micrograms) was quantitated from 5 mg of tissue wet weight. The limit of detection, on HPTLC, for the individual lipid classes was below 20 ng.

Animals↗

Pharmacokinetics of N4-behenoyl-1-beta-D-arabinofuranosylcytosine in patients with acute leukemia.

N4-Behenoyl-1-beta-D-arabinofuranosylcytosine (BHAC), a lipophilic and deaminase-resistant derivative of 1-beta-D-arabinofuranosylcytosine (ara-C), was studied pharmacologically in patients with acute leukemia. The concentrations of BHAC, ara-C, and 1-beta-D-arabinofuranosyluracil were measured by high-performance liquid chromatography, bioassay, and gas chromatography-mass spectrometry-mass fragmentography, respectively. The data of plasma BHAC concentrations were analyzed by a MULTI computer program. In seven patients given BHAC (200 mg/body weight; 2.97 to 4.26 mg/kg) i.v. for 90 min, the plasma disappearance curve of BHAC was biphasic with a mean initial half-life of 0.37 hr and a mean second half-life of 5.27 hr. The apparent volume of the central compartment and the apparent volume of distribution were 0.047 and 0.316 liter/kg, respectively; the systemic clearance was 0.051 liter/hr/kg. BHAC concentrations in erythrocytes were significantly higher (p less than 0.01) than those in plasma at 4 to 22.5 hr after infusion, suggesting that the erythrocytes may act as a reservoir for the drug. The plasma 1-beta-D-arabinofuranosyluracil level increased to 603 ng/ml at 4 hr after infusion, and it was over 129 ng/ml for at least 22.5 hr after infusion. Plasma ara-C levels, which could be detected in only 2 of 11 patients examined, were maintained (over 0.08 micrograms/ml) for 8 hr after infusion. Urinary BHAC excretion was less than 0.2 micrograms/ml of the sensitivity limit in all samples. Prolonged urinary ara-C excretion was detected, but it was only 0.5% of the administered BHAC for 24 hr. At 12 hr after a 200-mg infusion of BHAC, BHAC level in bone marrow fluid was significantly higher (p less than 0.01) than that in plasma. In spite of the lipophilic nature of the agent, the BHAC concentration in cerebrospinal fluid was less than 0.2 micrograms/ml in 8 of 9 patients without meningeal involvement. These findings were thought to indicate a restricted and prolonged BHAC distribution including plasma, blood cells, and bone marrow fluids, which may be of importance in the administration of BHAC in the chemotherapy of hematological cancers.

Acute Disease↗

Age-development changes in susceptibility of erythrocytes to perfringolysin O.

Susceptibility to perfringolysin O of erythrocytes from mice of different ages was examined. Erythrocytes of mice younger than 5 weeks' old were more resistant to the toxin than those of young adult and adult mice. Erythrocytes of aged mice were about 3.5 times more susceptible to the toxin than erythrocytes from 4-week-old mice. The membrane cholesterol content of erythrocytes appeared to be maintained at a constant level throughout the ages of mice examined. About 5% of the total membrane cholesterol was supposed to provide receptor sites for the toxin from an experiment in which cholesterol was specifically extracted by liposomes. It was demonstrated in this experiment that susceptibility of erythrocytes to the toxin was lost in proportion to the reduction in the toxin binding. The susceptibility, however, of erythrocytes from young or aged mice was much lower or higher than expected from the changes in toxin binding. Therefore, two possibilities were raised to account for age-related alterations in the susceptibility of erythrocytes; not only expansion of a particular compartment of membrane cholesterol as a toxin receptor but also some activation of intracellular reactions leading to hemolysis might occur in senescence.

Aging↗

Studies on viral respiratory disease in laboratory cats. I. Isolation of feline herpesvirus and choice of proper disinfectant.

In the laboratory cat colony consisted of 14 Korats and 8 Japanese native cats, the disease characterized by upper respiratory signs occurred. Seven cytopathogenic agents were isolated from the oropharyngeal swabs and necropsy materials of affected cats by means of inoculation to primary feline kidney cell cultures. One of the isolates (KS-1 strain) was identical with feline herpesvirus (FHV), and appeared to be a causal agent of the trouble. Properties of the KS-1 strain were in general agreement with the known strains of FHV. Serologic examination and clinical analysis suggested that Japanese native cats became carriers, re-excreted the virus and spread it to susceptible cats. Virucidal activities of several disinfectants against FHV, comparing with a feline calicivirus (FCV), were studied and the following conclusions reached: 1) Sodium hypochlorite, iodine complex, benzethonium chloride and chlorhexidine were effective against FHV at commonly used concentrations. 2) Among chemicals tested sodium hypochlorite was most effective against FCV and followed by iodine complex. 3) Benzethonium chloride and chlorhexidine had little efficacy against FCV at commonly used doses.

Animals↗

Characterization of GM1 ganglioside by direct inlet chemical ionization mass spectrometry.

Intact permethylated and permethylated-reduced (LiAlH4) derivatives of GM1 ganglioside were analyzed by direct inlet ammonia chemical ionization (CI) mass spectrometry. In addition, the trimethylsilylated derivative of the permethylated-reduced sample of this ganglioside was similarly analyzed. CI mass spectrometry proves to be a highly satisfactory method for structural studies of GM1 ganglioside because of the simple fragmentation pattern and the presence of prominent molecular ions and fragment ions in the high mass region. Complete information on the carbohydrate sequence and lipophilic composition can be easily obtained.

Animals↗

Functional life span of the corpus luteum gravidarum: an estimation from the mode of fluctuation of serum hormones after artificial termination of pregnancy and succeeding exogenous hCG administration.

Concentrations of estradiol (E2), progesterone (P), 17-hydroxyprogesterone (17-OHP), hCG and hPL were measured by radioimmunoassay in sera obtained serially from 35 subjects who received artificial termination of pregnancy and 24 of them were administered 10,000 IU of hCG 3 to 5 days later when endogenous hCG had sufficiently decreased. The subjects were operated respectively at 4-11 weeks (Group A) and 12-23 weeks (Group B) of gestation. In Group B, all the hormones declined promptly showing a hyperbolic pattern. In contrast, E2, P and 17-OHP in Group A revealed a significant delay of decline although hCG and hPL decreased as fast as hormones in Group B. When hCG was administered, P and 17-OHP showed a trend to elevate in Group A, but they showed a trend to decline in Group B. When compared in percentage value, the statistically significant difference is proved in 17-OHP between the two groups. The significant delay of E2, P and 17-OHP and the significant elevation of 17-OHP in Group A as compared with Group B were clearly demonstrated. Since 17-OHP is mainly of luteal origin, these findings seem to confirm that the corpus luteum gravidarum functions as far as 11 weeks of gestation and then involutes.

Abortion, Induced↗

[Ocular complications in chronic pansinusitis--report of two cases].

Case 1. A 38-year-old male was admitted with an 8-month history of progressive visual disturbance in his right eye. He had a past history of operations for paranasal sinusitis 24 years and 5 years prior to admission. Neurological examination revealed right anosmia, left hyposmia and vision in his right eye reducing to light perception. Case 2. A 61-year-old male was admitted with complaint of headache and a 2-month history of deteriorating vision in his right eye. On admission, vision in his right eye was found to be reduced to hand motions and associated with a concentric contraction of the visual field. Bilateral hyposmia and the right exophthalmos were also noticed. Plain x-ray films, tomography and especially CT scan were useful to demonstrate the definite inflammatory changes of the paranasal sinuses and the extension of the lesion beyond the confines of the sinuses. In both cases, external ethmoidectomy and sphenoidectomy with removal of the infected granulation tissue from the sinuses were performed, but neither mucocele nor pyocele was found. Vision improved postoperatively. Previous reports about ocular complications of infection in the paranasal sinuses without mucocele or pyocele are few. Early diagnosis of ocular complications of sinusitis is important. Once the diagnosis established, a timely surgical approach is essential to prevent visual loss.

Adult↗

[Moyamoya disease associated with a false aneurysm--case report and review of the literature].

A 67-year-old male was admitted to our clinic on May 1, 1981, because of mild confusion and a left hemiparesis. About 6 years ago, when he had a left-sided homonymous hemianopia, carotid angiography revealed moyamoya disease. CT scan on the admission showed an intracerebral hematoma in the right temporal lobe, which ruptured to the lateral ventricle. An angiogram demonstrated the net work of moyamoya vessels in the base of the brain and a "newly-appeared" aneurysm at the peripheral portion of the right anterior choroidal artery. This artery was shown on the previous angiogram also but did not bear the aneurysm. At the emergent operation the hematoma was evacuated and the aneurysm was excised, which was proved histologically to be a false aneurysm. Thirty-six cases of moyamoya diseases associated with aneurysm including the present case were reviewed. There were 44 aneurysms in this series. They were classified into groups--1) the major artery aneurysms arising from the major cerebral arterial segments; 2) the peripheral artery aneurysms arising from the distal segments of the peripheral cerebral arteries. The major artery aneurysms were found more frequently in the vertebro-basilar system, and the peripheral artery aneurysms in the basal ganglia, near or in the moyamoya vessels. Of 26 major artery aneurysms 12 were proved to be saccular aneurysms, 9 by surgeries and 3 by autopsy studies respectively. Of 18 cases of the peripheral group the aneurysms were excised operatively in two cases, and autopsy studies were performed in other two cases. The peripheral artery aneurysms were examined histologically in three cases; one was proved to be a false aneurysm, the other was thought to be a true aneurysm, and the third one was not verified. In 8 cases, the peripheral artery aneurysms disappeared on the follow-up angiograms and were supposed to be false aneurysms. From these reported cases, it may be suggested that major artery aneurysms are mainly true aneurysms and peripheral artery aneurysms are false aneurysms.

Aged↗

Four positional isomers of sialyloligosaccharides isolated from the urine of a patient with sialidosis.

Four positional isomers of sialyloligosaccharides were isolated from the urine of an adult patient with sialidosis with partial deficiency of beta-galactosidase. From structural studies including compositional sugar analysis, exoglycosidase digestion, chemical ionization mass spectrometry, proton nuclear magnetic resonance spectrometry, and methylation analysis, their structures were deduced to be as follows: 1. AcNeu alpha 2 leads to 3 Gal beta 1 leads to 4GlcNac beta 1 leads to 2Man alpha 1 leads to 3Man beta 1 leads to 4GlcNac 2. AcNeu alpha 2 leads to 3Gal beta 1 leads to 4GlcNac beta 1 leads to 2Man alpha 1 leads to 6Man beta 1 leads to 4GlcNac 3. AcNeu alpha 2 leads to 6Gal beta 1 leads to 4GlcNac beta 1 leads to 2Man alpha 1 leads to 3Man beta 1 leads to 4GlcNac 4. AcNeu alpha 2 leads to 6Gal beta 1 leads to 4GlcNac beta 1 leads to 2Man alpha 1 leads to 6Man beta 1 leads to 4GlcNac Sialyloligosaccharides 1 and 3 have previously been found in the liver and urine of patients with mucolipidosis I, II, and variable forms, but sialyloligosaccharides 2 and 4 have not previously be found in human urine.

Carbohydrate Conformation↗

Characterization of a novel glycosphingolipid, ceramide nonasaccharide, isolated from spermatozoa of the fresh water bivalve, Hyriopsis schlegelii.

A new glycosphingolipid, provisionally named Lipid III in our previous work (Hori, T., Sugita, M., Kanbayashi, J., and Itasaka, O. (1977) J. Biochem. (Tokyo) 81, 107-114), was extracted and purified from the spermatozoa of the fresh water bivalve, Hyriopsis schlegelii. The yield of the glycolipid was 1.8 mg/g dry weight of the spermatozoan preparation. Its chemical structure was characterized by compositional analysis, partial acid hydrolysis, methylation analysis, and proton nuclear magnetic resonance spectroscopy. The following structure is proposed: 3-O-MeFuc alpha 1 leads to 2.3-O-MeXyl beta 1 leads to 4(3-O-MeGalNAc alpha 1 leads to 3)Fuc alpha 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 3(Xyl beta 1 leads to 2)Man beta 1 leads to 4Glc beta 1 leads to 1Cer. This glycolipid contains the same backbone as the pentaglycosyl ceramide (Lipid II) reported previously (Hori, T., Takeda, H., Sugita, M., and Itasaka, O. (1977) J. Biochem. (Tokyo) 82, 1281-1285). Lipid III is structurally related to Lipid II by linking it with a fucose and three kinds of O-methyl sugars, namely, 3-O-methylxylose, 3-O-methylfucose, and 3-O-methyl-N-acetylgalactosamine, through an internal fucose moiety. Unlike most vertebrate glycolipids, Lipid III appears to be unique in having an internal fucose and O-methyl sugars as well as mannose. To our knowledge, this is the first instance for the natural occurrence of 3-O-mehylxylose. Aliphatic constituents of the lipid are palmitic acid and stearic acid as the principal fatty acids, and octadeca-4-sphingenine as the major long chain base.

Animals↗

Myelin gangliosides: an unusual pattern in the avian central nervous system.

Gangliosides were isolated from purified myelin obtained from brain and spinal cord of mature chickens and pigeons. Total concentrations were approximately two- to fivefold greater than for previously reported mammalian species, and their patterns also differed in containing significantly more sialosylgalactosylceramide (GM4). The latter comprised one-third to one-fourth of total myelin ganglioside, approximately equivalent to GM1 (II3NeuNAcGgOse4Cer). As in mammals, GM4 of avian CNS appeared to be localized in myelin. Fatty acids of this ganglioside included both the hydroxy- and unsubstituted types, and long-chain bases were almost entirely C18. Ganglioside GM1 split into two closely migrating bands on TLC, the slower of which resembled mammalian GM1 in having stearate as the main fatty acid with a measurable amount (10%) of C20-sphingosine; the faster band had predominantly longer-chain fatty acids and very little C20-sphingosine.

Animals↗

Lateral hypothalamic mediation of midbrain catecholaminergic influences on preovulatory surges of serum gonadotropin and prolactin in female rats.

To investigate the involvement of the midbrain ascending pathways in the control of ovulation, bilateral coronal transections were produced at three rostro-caudal levels in the lateral hypothalamus as well as in the lateral forebrain on the day of proestrus. Although lateral forebrain transections failed to block spontaneous ovulation, transections in both the anterolateral hypothalamus (ALH) and the midlateral hypothalamus blocked ovulation and the proestrous surges of serum LH, FSH, and PRL. When electrochemical stimulation was applied to the diagonal band of Broca, ovulation could be induced in animals with ALH transections. Moreover, the effects of intraventricular saline, norepinephrine (NE; 40 microgram), or dopamine (40 microgram) on the induction of preovulatory surges of serum gonadotropin and PRL were examined in proestrous rats with ALH transections. Ovulation was restored by the intraventricular injection of NE, but not of dopamine. In ALH-transected animals which ovulated in response to intraventricular NE, serum concentrations of LH, FSH, and PRL were higher than those of ALH-transected animals injected with saline. These results suggest that the lateral hypothalamus plays an important role in the control of preovulatory surges of serum gonadotropin and PRL by mediating the midbrain catecholaminergic innervation of the preoptic-hypothalamic area.

Animals↗

Effect of ouabain on electrical coupling of rabbit atrial muscle fibers.

The effects of ouabain on passive electrical properties of isolated rabbit atrial muscle fibers (crista-terminalis) were investigated. The space constant as well as the time constant of the crista-terminalis was determined using the partition method of Kamiyama and Matsuda based on the cable equation proposed by Hodgkin and Rushton. Ouabain treatment for 30 minutes at a lower concentration (2 X 10(-7) M), caused no significant change in the space constant and time constant of the crista-terminalis. After ouabain treatment for 30 minutes at a higher concentration (1 X 10(-6) M), the space constant of the crista-terminalis was reduced significantly, whereas the time constant was not affected. An apparent reduction in the resting membrane potential and the amplitude of action potential was also observed at the higher concentration of ouabain. These effects of ouabain on passive electrical properties of the crista-terminalis are most likely explained by the increase of its axial resistance (electrical uncoupling) due to intracellular calcium accumulation resulting from inhibition of the membrane sodium pump. This suggests that such an electrical uncoupling may play an important role in the intra-atrial conduction disturbance by cardiac glycosides.

Action Potentials↗