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Biomedical subjects

Y Sakata

Publications and source records attributed to Y Sakata.

At least 487 records · Page 27Linked to original sources
PubMed1981

Direct effects of endogenous pyrogen on medullary temperature-responsive neurons in rabbits.

The effect of endogenous pyrogen (E.P.) injected directly into the tissue near the recording site were examined on the activities of the medullary temperature-responsive (TR) neurons in rabbits anesthetized with urethane. Endogenous pyrogen prepared from rabbit's whole blood was administered by a fine glass cannula (100-200 micrometer in diameter) in a fluid volume of 1 to 4 microliter. The cannula was fixed to the manipulator in parallel with a microelectrode and their tips were less than 0.05 mm apart. In rabbits with the intact preoptic/anterior hypothalamic (PO/AH) region, 4 warm-responsive neurons out of 7 were inhibited and 6 cold-responsive neuron out of 7 were excited by the direct administration of the E.P. In rabbits with lesions of the PO/AH, 5 warm-responsive neurons out of 9 were inhibited and 6 cold-responsive neurons out of 8 were facilitated by E.P. Antipyretics administered locally after the E.P. antagonized the pyretic effect, causing a return of the discharge of TR neuron to the control rate within 2.4 +/- 1.2 (mean +/- S.D.) min. The medullary TR neuron itself has the ability to respond to the E.P. and contributes to the development of fever.

Animals↗
PubMed1981

[Absorption, excretion and clinical trials of cefroxadine in the field of pediatrics (author's transl)].

A study was made with the newly developed cefroxadine (CXD) dry syrup by measuring the serum level, urine excretion and recovery rate in 10 children who were orally administered 5, 10 and 20 mg/kg at 1 hour after meals and the following results were gained. Also, its clinical efficacies and side effects were investigated in the following cases who were treated with a mean dose of 33 mg/day divided into 3 to 4 portions for a period of 9 days on the average; viz. a total of 151 cases consisting of 9 cases of pharyngitis, 39 of tonsillitis, 11 of streptococcal infection, i.e. scarlet fever, 7 of bronchitis, 6 of pneumonia, 1 of otitis media, 6 of purulent lymphadenitis, 1 of purulent parotitis, 1 of subcutaneous abscess and 3 of impetigo. 1. The serum level tends to reach its maximum level within 1 hour after administration. The mean concentrations of 5, 10 and 20 mg/kg dose in the foregoing time were 6.35, 9.12 and 21.62 mcg/ml respectively and dose response was observed. CXD showed higher concentration than CEX, CED and CFT. The mean half-life periods of the 3 dose were 72, 84 and 66 minutes respectively and variations were observed, but the drugs maintains a satisfactory serum level. 2. The time which showed highest urine excretion was mainly in the 0 to 2 hours bracket and the average concentrations of 5 , 10 and 20 mg/kg dose in the foregoing time were 381.2, 771.7 and 1,577.7 mcg/ml respectively. The dose response was more evident than in the serum concentrations. The average recovery rates within 6 hours were 93.6, 88.3 and 94.3% respectively and they were similar to those of CEX, CED and CFT. 3. The clinical effects were evaluated were in 148 cases out of the total of 151 and 136 cases, or 91.9% showed good or excellent efficacy response. 4. The daily dose groups of less than 30 mg/kg and 31 to 40 mg/kg formed the majority and there was no difference in the comparison of the clinical effectiveness in these 2 groups. Administration of a daily dose of 20 to 40 mg/kg is sufficient for the treatment of the aforementioned mild diseases except for pneumonia. 5. The clinical effects were compared between the 3 and 4 times a day treatment groups, but there was no difference between these two groups with regard to the foregoing daily dose. The 3 times a day treatment is acceptable, but the 4 times a day treatment is preferable when pharmacokinetics if taken into account. 6. The bacteriological effects in 41 cases, or 97.6% out of the 42 cases were above the efficacy base line and a high efficacy rate was achieved. 7. With regard to side effects, diarrhea developed in 4 cases and eosinophilia in 6 cases, abnormal simultaneous increases in GOT and GPT in 1 case and 1 case each for abnormal values in LDH and BUN were seen in the clinical test values. The foregoing results show that CXD has high efficacy and safety and it can be said that it is a drug required in the pediatric field.

Adolescent↗
PubMed1981

[Clinical trials of cefroxadine on skin and soft tissue infections in the field of pediatrics (author's transl)].

CXD was administered orally at an average dose of 28.6 mg/kg (18.3 approximately 42.3 mg/kg) for an average 6 days (3 approximately 12 days) to a total of 99 pediatric cases with skin and soft tissue infections (impetigo 89, abscess 7 and furuncle 3) ranging from 3 months to 9 years old. The drug was given twice to 4 times per day after meals. The clinical and bacteriological effects and adverse reactions of CXD as well as the susceptibility of the causative organisms against CXD and CEX were studied, and the results obtained are as described below: 1. According to judgement of the attending doctors, CXD had a high global efficacy rate of 90.9%. 2. Analysis of the attending physicians' evaluations of the clinical effects on impetigo revealed that a dose of CXD 20.5 approximately 30.4 mg/kg t.i.d. can produce satisfactory responses. 3. According to the assessments by Evaluation Committee, the global clinical effects after 3, 5 and 7 days were 81.4, 91.2 and 94.6%, respectively. This indicates that clinical responses increased with prolongation of the treatment period, viz. better responses obtained after 5 and 7 days. This suggests that a minimum of 5 days administration is required for treating these infections. 4. As for impetigo having the largest number of patients in this study, a dose of CXD 20.5 approximately 30.4 mg/kg per day seemed to produce satisfactory clinical effects. 5. As for dose per day, the t.i.d. regimen of CXD 20.5 approximately 30.4 mg/kg seemed to exhibit satisfactory clinical responses, as already mentioned. Because of quite a small number of patients on the q.i.d. regimen of higher doses, however, the question of whether the t.i.d. treatment with 20.5 approximately 30.4 mg is adequate or not should be determined by a comparative study between the q.i.d. and t.i.d. treatments. 6. As for bacteriological responses, a high global effect of 87.1% was obtained with CXD against S. aureus and S. pyogenes isolated from 74 and 1 cases, respectively. 7. As for impetigo with predominant number of cases, CXD was highly effective bacteriologically at a daily dose of 20.5 approximately 30.4 mg/kg t.i.d. As an appropriate comparative evidence with the q.i.d. treatment was lacking, however, therapeutic validity of the t.i.d. treatment could not be determined definitely. 8. Utility was evaluated by the attending physicians on the total 99 cases, and CXD showed as high as 88.9%. 9. There were neither non-compliances nor adverse reactions to this treatment. 10. CXD showed a distribution of antimicrobial activity similar to that of CEX, against 74 isolates of S. aureus with the MICs of CXD ranging from 1.56 to 25 mcg/ml and those of CEX ranging from 0.78 to 25 mcg/ml, with peak MIC being 3.13 mcg/ml for both drugs. As for S. pyogenes, only one isolate from the same species, CXD was antimicrobial activity at 0.2 mcg/ml and CEX was antimicrobial at 0.39 mcg/ml. The above findings suggest that CXD is highly effective against acute skin and soft tissue infections in pediatrics.

Abscess↗
PubMed1981

[Laboratory and clinical evaluation of cefoxitin in children (author's transl)].

Pharmacokinetics of cefoxitin, a new injectable semisynthetic-cephamycin, was studied in 12 healthy children and also was studied cerebrospinal fluid levels in 1 patient with bacterial meningitis received 44.5 mg/kg of cefoxitin and thoracic fluid levels in 2 patients were measured. Cefoxitin was administered intravenously to 50 patients with various types of infections an average dose of 130 mg/kg/day for an average of 9 days. The results were as follows: 1. Favorable plasma levels were obtained comparing with those off conventional injectable cephalosporins after 15 mg/kg and 25 mg/kg of cefoxitin for one shot intravenous injection. The half lives of cefoxitin in the plasma were about 15.9 minutes up to 1 hour and 25.5 minutes up to 2 hours after an intravenous administration of cefoxitin at a dose of 15 mg/kg, and while, those were 15.9 minutes and 27.5 minutes after an intravenous administration of cefoxitin at a dose of 25 mg/kg, respectively. 2. Cefoxitin was excreted with high concentration up to 2 hours after the administration and thereafter, urinary concentration of cefoxitin declined rapidly with the lapse of time. The time course urinary concentration reflected those of plasma levels. Approximately 94.7% and 90.6% of dosed cefoxitin were recovered in the urine for 6 hours after the administration at the dose of 15 mg/kg and 25 mg/kg, respectively. 3. The cerebrospinal fluid levels of cefoxitin were only determined in a patient of bacterial meningitis. Therefore, further study should be performed. 4. The thoracic fluid levels with 2 patients were higher than cerebrospinal fluid levels. 5. Among the 50 patients with various infections, cefoxitin was clinically effective in 84% and bacterial response in 87%. 6. As adverse reactions, in total 79 patients included exclusive 29 patients, diarrhea occurred in 1 patient, sweating and cough in 1 patient, rash with fever in 4 patients, vascular pain in 2 patients, and leukopenia was observed in 1 patient, eosinophilia in 1 patient, and increase of GOT and LDH were observed in each 2 patients. The other adverse reactions were not experienced.

Adolescent↗
PubMed1980

Visceral larva migrans caused by Trichuris vulpis.

Two brothers with visceral larva migrans caused by Trichuris vulpis were diagnosed after they had been investigated for an eosinophilia. Both patients were almost asymptomatic. The diagnosis of visceral larva migrans was based on the results of immunoelectrophoretic studies and no liver biopsy was performed. After administration of thiabendazole, the number of eosinophils and serum total IgE levels gradually decreased, and the patients have remained well.

Animals↗
PubMed1980

Cross-linking of alpha 2-plasmin inhibitor to fibrin by fibrin-stabilizing factor.

The concentration of alpha 2-plasmin inhibitor in blood plasma is higher than that in serum obtained from the blood clotted in the presence of calcium ions, but is the same as that in serum obtained in the absence of calcium ions. Radiolabeled alpha2-plasmin inhibitor was covalently bound to fibrin only when calcium ions were present at the time of clotting of plasma or fibrinogen. Whereas, when batroxobin, a snake venom enzyme that lacks the ability to activate fibrin-stabilizing factor, was used for clotting fibrinogen, the binding was not observed. When fibrin-stablizing, factor-deficient plasma was clotted, the specific binding of alpha 2-plasmin inhibitor to fibrin did not occur even in the presence of calcium ions and the concentration of alpha 2-plasmin inhibitor in serum was the same as that in plasma. Monodansyl cadaverine, a fluorescent substrate of the fibrin-stablizing factor, was incorporated into alpha 2-plasmin inhibitor by activated fibrin-stablizing factor. All these findings indicate that alpha 2-plasmin inhibitor is cross-linked to fibrin by activated fibrin-stabilizing factor when blood is clotted. Analysis of alpha 2-plasmin inhibitor-incorporated fibrin by sodium dodecyl sulfate gel electrophoresis showed that the inhibitor was mainly cross-linked to polymerized alpha-chains of cross-linked fibrin. Cross-linking of alpha 2-plasmin inhibitor to fibrin renders fibrin clot less susceptible to fibrinolysis by plasmin.

Calcium↗
PubMed1980

[Treatment of whooping cough and whooping cough syndrome by cefoperazone (author's transl)].

Clinical trial of cefoperazone (CPZ) for the treatment of whooping cough and whooping cough syndrome was performed and the following results were obtained. 1) In 18 cases suffering from whooping cough, CPZ was given 47 approximately 106 mg/kg/day (average 72 mg/kg/day) by intravenous route. The clinical efficacy rates judged by doctors in charge were 44% on the 3 rd day, 75% on the 7 th day, 86% on the period day. And in these cases, the clinical efficacy rates judged by committee members were 56%, 83% and 86%. 2) In 6 cases diagnosed as whooping cough syndrome, CPZ was given 49 approximately 96 mg/kg/day (average 59 mg/kg/day) by the same route. The clinical efficacy rates judged by doctors in charge were 67% on the 3 rd day, 80% on the 7 th day and 75% on the period day. And in these cases, those judged by committee members were 83%, 80% and 100%. 3) In 1 case, Bordetella pertussis was searched and showed 0.012 mcg/ml of MIC. It was eliminated on the 1 st day after administration. 4) Doctors in charge judged the utility of CPZ for whooping cough. Twelve cases were useful and 6 cases were slightly useful. 5) No side effects were observed except for elevation of GOT and LDH. These results suggest that CPZ might be useful drug against whooping cough.

Bordetella pertussis↗
PubMed1980

[Laboratory and clinical studies on cefoperazone in pediatrics treatment (author's transl)].

Laboratory and clinical studies of cefoperazone (CPZ), a new semisynthetic cephalosporin, were investigated and following results were obtained. (1) Blood level: CPZ was given intravenous dose of 25 mg/kg and 50 mg/kg to each 3 children. In the former, the blood level of 15 minutes after injection was 194.2 mcg/ml on average and the half life was 106.2 minutes. In the latter, the blood level was 320.0 mcg/ml on average and half life was 102.2 minutes. (2) Urinary concentration: In the cases of the dose of 25 mg/kg, 35.9% of CPZ was recovered on average from the urine within 6 hours after injection, and the urinary concentration reached to 2,148.6 mcg/ml (0 approximately 2 hours). And in the cases of the dose of 50 mcg/kg, the recovery rate in urine was 43.6%, and the urinary concentration was 3,008.3 mcg/ml. (3) Cerebrospinal fluid level: CSF level was determined in a patient with bacterial meningitis by S. pneumoniae. Ninety mg/kg of CPZ were given intravenous injection. After 60 minutes CSF level was 3.35 mcg/ml, and after 80 minutes the blood level was 192.0 mcg/ml. (4) Bacteriological evaluation: Against 164 strains isolated clinical specimens, the bacteriological evaluation on CPZ was performed in comparison with cefotaxime (CTX), cefazolin (CEZ) and piperacillin (PIPC) by inoculum size of 10(8) cells/ml. CPZ showed antibacterial activity against Gram-negative bacteria almost similar to CTX and PIPC. (5) CLINICAL RESULTS: CPZ was given 48.3 approximately 360 mg/kg/day (average 146.1 mg/kg/day) by intravenous route to 46 patients with various infection. The overall efficacy rate was 80.4%. The rate of bacteriological effectiveness was 78.9% in 19 cases. (6) Side effects: As side effects, diarrhea, fever, rash, urticaria, leukopenia, eosinophilia, elevation of GOT, GPT, and LDH were observed, but not seriously.

Adolescent↗