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Biomedical subjects

S Oka

Publications and source records attributed to S Oka.

At least 505 records · Page 28Linked to original sources

Simultaneous microdetermination of capsaicin and its four analogues by using high-performance liquid chromatography and gas chromatography--mass spectrometry.

An improved method is described for the simultaneous determination of capsaicin and its analogues at levels from nanograms to micrograms using high-performance liquid chromatography (HPLC) and gas chromatography--mass spectrometry. This method consists of two steps: firstly, purification and determination of total capsaicinoid by HPLC, and secondly, the simultaneous determination of capsaicin and its analogues by mass chromatography (MC) or mass fragmentography (MF). Crude extracts of capsaicinoid were purified with a Zorbax SIL column. Total capsaicinoid was detected at 235 nm and measured automatically by a microcomputer. It was collected, evaporated, trimethylsilylated and subjected to MC or MF. After monitoring the molecular ions of trimethylsilyl derivatives of capsaicinoid and the internal standard, the absolute contents of each analogue were determined by computer. By using this method, capsaicin and all of its analogues can be determined simultaneously at levels from micrograms to nanograms without any interferences from other components.

Capsaicin↗

Purification of two types of sea-squirt antigens.

Under monitoring the antigenic activity by radioimmunoassay (RIA), one of the major sea-squirt antigens was isolated by gel chromatography after treatment of the extract from internal organs of sea-squirt with QAE-Sephadex. This antigen was fairly homogenous as judged from its elution profile in chromatography on a column of Ultrogel AcA 44 with respect not only of the antigenic activity but also to UV absorption. Furthermore, the antigen inhibited the binding of the 125I-labeled tracer antigen to rabbit anti-sea-squirt antibody in a similar mode to the case of Ei-2, one of the sea-squirt antigens previously prepared, but its specific activity was as high as 2.33 times that of Ei-2. Accordingly this isolated antigen was corresponded to the major antigenic substance in Ei-2 and referred to as Ei-M. In addition, the other antigen of Gi-x was also isolated by chromatography on a column of Sepharose 6B as the major antigenic substance in Gi-2, the other one of the previous antigens. Gi-x was apparently different from E-M in the mode of inhibition of the binding of the tracer antigen to the antibody, although its antigenic activity against the asthmatic patients in vivo was as high as that of Ei-M. Thus, it was considered that sea-squirt contained at least two types of antigens of Ei-M and GI-X.

Amino Acids↗

A kinetic measurement of red cell deformability: a modified micropipette aspiration technique.

A kinetic measurement of the red cell deformability is developed, modifying the micropipette aspiration technique of BRAASCH (1971). The sedimented human red cells on a slide-glass are individually aspirated into a micropipette by negative pressure (delta P), and the decreasing "velocity (v)" of the applied electric current, due to the aspirating cell, is taken as a measure of the "easiness" of the cell to enter into the small orifice of the micropipette (inner diameter, 2 R congruent to 3 micrometer). An empirical relation, v infinity (pi r2) . (delta P) . ("deformability"), is obtained. In order to test the validity of the method, some factors influencing the deformability are studied: i.e., the "velocity" decreases as lowering temperature; the "velocity" of the glutaraldehyde-pretreated cells and of both in vivo and in vitro aged cells decreases. Therefore, the parameter, "velocity (v)," reflects the deformability well. In addition, if a few assumptions could be allowed, v would be related to the Young's modulus of the membrane.

Erythrocyte Aging↗

[Fundamental and clinical studies on CS--1170 in pediatric field (author's transl)].

Fundamental studies and clinical evaluation of CS-1170 were carried out in the field of pediatrics, and the following results were obtained: 1) A high serum concentration of the drug was observed by 30 minutes after the commencement of intravenous drip infusion of 20 and 30 mg/kg, with the peak appearing at the end of the infusion. Serum level of 10.0 micrograms/ml or more was observed even 2 hours after the completion of the drip infusion. 2) The peak of serum concentration appeared at 30 minutes after intravenous injection of 20 mg/kg, and the blood level 4 hours after the injection was 4.3 micrograms/ml or more. 3) Excretion of the drug into the urine by 6 hours after intravenous drip infusion or one-shot injection was 60% or more on the average, with the major portion of the drug in the active state excreted by 4 hours after the administration. 4) Twenty-five children with acute infections (5 types of diseases) were treated with CS-1170 mainly by intravenous drip infusion, and the following clinical results were obtained: The overall clinical effective rate of 96.0% was obtained with the daily dosage of CS-1170 ranging mostly from 50 to 80 mg/kg in the total 25 cases including 7 cases of acute bronchitis (100%), 13 cases of bronchopneumonia (92.3%), 3 cases of acute urinary tract infections (100%), a case each of staphylococal exanthema and lymphadenitis in the neck (100%). 5) Thorough analyses of the liver and kidney functions and the hematological features at the time of, and about 10 days after the administration of CS-1170 in each case so far revealed no abnormality. The drug did not affect the site of injection or the whole body.

Age Factors↗

[A clinical study of intravenous doxycycline in the pediatrics field (author's transl)].

An intravenous preparation of doxycycline (DOTC, Vibramycin 'Pfizer'), a long-lasting tetracycline, was administered mainly by drip infusion for a series of study in the pediatrics field, and the results were as follows: 1) DOTC (100 mg) was dissolved in a 100 ml of glucose solution and 2--3 mg/kg was administered intravenously. When the total infusion time was adjusted between one to two hours, the peak serum level of DOTC was seen at the end of infusion in each case. The serum level in a two-hour infusion time, however, the serum level was delectable for a long period of time: the serum level after 10 hours was 0.82--1.23 micrograms/ml. Above results suggest that DOTC intravenous should be given in a two-hour infusion twice a day for applicable infections in the pediatrics field. 2) Urine excretion of DOTC was about a half (50%) of the administered dosage. 3) DOTC was given mostly at about 3--5 mg/kg per day (twice a day) infusion to 25 children with five infections, viz. acute angina lacunaris, acute bronchitis, bronchopneumonia, Mycoplasma pneumonia and acute urinary tract infections. A clinical improvement seemed attributable to DOTC was clearly observed in 23 out of 25 patients (92%). 4). DOTC infusion was also effective for Mycoplasma meningoencephalitis, severe Mycoplasma pneumonia associated with pleuritis, bronchitis and bronchopneumonia with a lot of Staphylococcus aureus identified in the sputum medium, acute urinary tract infections caused by E. coli. 5) Before and ten days after DOTC infusion, laboratory tests for liver and renal functions and blood were performed. No noticeable abnormalities were found except one case with transient GOT and GPT elevations. Above summary was presented at the 26th annual meeting of Japan Society of Chemotherapy in June 1978.

Bronchitis↗

[Laboratory and clinical study of cefamandole by intravenous injection in the pediatric field (author's transl)].

Cefamandole sodium (CMD) was intravenously administered and following laboratoric and clinical results were obtained. (1) The peak blood concentration was 32 approximately 44 micrograms/ml when the drip infusion was finished. At 1 hour after the end of the drip infusion the blood concentration was 7.6 approximately 8.1 micrograms/ml. Half life was approximately 0.64 hours. (2) Urinary recovery rate was 84.5 approximately 95% in active state within 6 hours. (3) Penetration of cerebrospinal fluid was found in 2 cases. (4) In most of 170 strains of Streptococcus haemolyticus MICs of cefamandole were 0.05 microgram/ml. They were less susceptible to cefazoline, cefmetazole and ceftezole. (5) CMD was administered to 35 pediatric patients (upper or lower RTI, lymphadenitis, enteritis or UTI) at 100 mg/kg/day for 3 approximately 9 days, the efficacy rate was 97.1%. (6) Side effect: Rash occurred in one case, and eosinophilia was observed in 4 cases. No abnormal finding of renal and liver function was observed.

Bacterial Infections↗

[Fundamental and clinical studies of cefuroxime, a new cephalosporin antibiotic, in pediatric field (author's transl)].

A series of studies on cefuroxime (CXM) were carried out and the following results were obtained. 1) Most of MICs to recent clinical isolates of Group A hemolytic Streptococcus were less than 0.0125 micrograms/ml. 2) A single intravenous bolus dose of 36.5 mg/kg of CXM was given to two children, and the peak blood levels of 30 and 40 micrograms/ml were obtained at 30 minutres after injection; mean half-life in blood was 1.02 hours. The doses of 25 approximately 50 mg/kg were given over 1 hour by intravenous instillation to six children. The peak blood level appeared at the end of instillation, and half-life in blood was distributed between 0.56 and 0.81 hour. With both of these administrations, measurable blood levels were maintained up to 6 hours, and urinary excretion rate in active form up to 6 hours was distributed between 40.5 and 96%. 3) Serious upper respiratory tract inflammations, low respiratory tract inflammations (acute bronchitis and bronchopneumonia), staphylococcal exanthema and acute urinary tract infections mostly responded well to CXM intravenous administration (one shot injection, or instillation at dose of 50 approximately mg/kg/day in 2 approximately 3 daily divided doses. 4) Staphylococcal pyothorax was completely cured by 17 day-long CXM intravenous instillation at dose of about 150 mg/kg/day. 5) No difference in CXM therapy result was seen between the two administration forms used, i.e., one shot injection and instillation. 6) Clinical efficacy rate in 48 patients was 100% (excluding 1 unassessable case). As for side effect, transitory elevation of GPT and Al-P were seen in only 1 case each. The summary of this paper was reported on June 9, 1979 at 27th General Meeting of Japan Society of Chemotherapy (Fukuoka).

Bacterial Infections↗

Quinacrine and acridine-R banding without a fluorescence microscope.

A technique is described in which a standard fluorescence microscope equipped with a high-pressure mercury lamp is replaced with an ordinary laboratory microscope fitted with a quartz-iodine lamp. A dark field condenser and a set of three filters, including an FITC interference filter, complete a 'fluorescence' microscope. The microscope has proved itself satisfactory in the study of Y-chromatin, chromosome Q-bands including Q-polymorphism, and acridine-R band. It is very easy to operate and does not emit ultraviolet light, which might harm operators. Total cost of the quartz-iodine lamp's outfit, filters, and a dark-field condenser is much less than that of a standard fluorescence microscope. The cost is especially low when a laboratory microscope with a quartz-iodine lamp is already at hand. Spectrofluorometric studies of QM and Q indicate that the present system will show even better performance if an interference filter with a transmission range of about 400 to 440--450 nm is designed and used in combination with a 455--475 nm barrier filter.

Acridines↗

[Fundamental and clinical studies in pediatrics on PC-904, a penicillin with broad spectrum newly developed in Japan (author's transl)].

Fundamental and clinical studies of PC-904, a newly developed penicillin with a broad spectrum, were performed and the following results were obtained. (1) The serum levels of PC-904 after 1.5 hours drip infusion reached the peak at 1 hour or at the end of the infusion and the detectable levels of PC-904 were maintained up to 2 or 3 hours after the end of the infusion. (2) The urinary excretion rates up to 6 hours after the onset of the infusion were 19.2 approximately 25.5%. (3) Forty-one patients were treated with PC-904 and the majority of the diseases were acute respiratory infections. The treatment by the drip infusion of 50 approximately 100 mg/kg/day resulted in good responses to whooping cough, and lacunar tonsillitis, lymphadenitis and staphylococcal scald skin syndrome resistant to the treatment by ampicillin and cephalexin. The satisfactory results were also obtained by the treatment of almost the same dosage in the patients with acute bronchitis, bronchopneumonia and measles pneumonia. (4) Staphylococcus aureus and Klebsiella pneumoniae were isolated from the sputum culture of the patients with bronchopneumonia and they responded well to the treatment with PC-904. (5) The drip infusion of 60 approximately 70 mg/kg/day for 5 approximately 6 days was shown to be useful in the treatment of urinary tract infection of which the causative organism was E. coli. (6) No side effects were observed except rubella-like eruption in one case. (7) Clinical evaluation was examined in all cases except one patient of which the medication was withdrawn due to eruption, and the overall clinical efficacy was excellent or good in all of 40 cases.

Age Factors↗

LBA technique in the detection of chromosome variants. I. Chromosomes with known sites of Q variants.

A method is described (LBA method) which used DNA replication pattern in the detection of chromosome variants in man. In Part I, results on chromosomes with known sites of Q-variants, i.e., 5 pairs of acrocentrics, as well as 3 and 4, were presented. Fourty-one variants were detected in a total of 40 acrocentrics. Twenty-eight of them were detected only by the LBA technique; 11 of them being in short arms and 17 of them in centromeres. Seven variants, including 4 of those in satellites, were detected only in QFQ-stained metaphases. Six short-arm variants were observed by both methods. It appears that a sequential QFQ-LBA technique is very useful in the detection of variants in D- or G-group chromosomes.

Centromere↗