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Biomedical subjects

M Katayama

Publications and source records attributed to M Katayama.

At least 289 records · Page 16Linked to original sources

[Study on the use of cefotiam in neonates].

Pharmacokinetic and clinical studies were carried out regarding the use of cefotiam (CTM) in the treatment of infections in newborn infants. Absorption and excretion: CTM was administered by bolus intravenous injection at a dose of 20 mg/kg to 9 newborns ranging in age from 1 to 28 days (gestational age, 34-40 weeks; birth weight, 2,000-3,380 g) and 6 infants aged 30 to 87 days (gestational age, 33 approximately 40 weeks; birth weight, 2,100-3,600 g) and its serum concentration and urinary excretion were determined. In the newborns, mean serum concentrations were 43.3 micrograms/ml at 1/4 hour, 36.7 microgram/ml at 1/2 hour, 27.8 micrograms/ml at 1 hour, 17.7 micrograms/ml at 2 hours, 8.8 micrograms/ml at 4 hours and 4.8 micrograms/ml at 6 hours, and in the infants, they were 44.5 micrograms/ml, 31.2 micrograms/ml, 19.1 micrograms/ml, 7.6 micrograms/ml, 2.2 micrograms/ml and 0.7 micrograms/ml at the above sampling times, respectively. Mean half-lives were 1.92 hours for the newborns and 0.96 hour for the infants, and mean urinary recoveries within 6 hours were 41.2% and 50.1% for the newborns and the infants, respectively. Taking individual differences into account, serum peak levels (at 1/4 hour) in newborns were very similar to each other irrespective of age (days after birth), and did not appear to be greatly different from those in infants. Half-lives, however, became shorter with aging, and the half-life of the serum CTM level in infants of about 1 month old should be close to those in young children or school-age children. From these observations, it is suggested to establish a standard regimen in which CTM is administered at a dose of 20 mg/kg once or twice a day to newborns within 3 days after birth, twice or 3 times a day to those aged 4 to 7 days, and 3 or 4 times a day to those aged 8 days or older. Clinical study: The CTM was administered to 11 patients with acute pneumonia, 2 patients each with suspected septicemia and with bullous impetigo, 1 patient with purulent lymphadenitis, 3 patients with idiopathic respiratory distress syndrome and 1 patient with pneumothorax, and its clinical effect was investigated. Excellent responses were observed in 12 of the 15 evaluated cases,good responses in 2, and a poor response in 1, thus an overall clinical effectiveness was 93.3%.(ABSTRACT TRUNCATED AT 400 WORDS)

Absorption↗

Expression of glial fibrillary acidic protein in the CNS and PNS of murine globoid cell leukodystrophy, the twitcher.

The expression of glial fibrillary acidic protein (GFAP) was found to be markedly enhanced immunohistochemically and biochemically both in the central (CNS) and peripheral (PNS) nervous systems of the twitcher mutant, an authentic murine model of human globoid cell leukodystrophy. The astrocytes in the CNS, the unmyelinated Schwann cells in the sciatic nerve, and the satellite cells in the trigeminal ganglion stained heavily with anti-GFAP antiserum. These changes in GFAP expression occurred shortly before the initiation of demyelination and coincided chronologically and topographically with infiltration of macrophages, suggesting that the same or closely related factors trigger the infiltration of macrophages and activate expression of GFAP. Cytoskeletal protein preparations showed increases in GFAP as well as in vimentin in the brainstem, spinal cord, and sciatic nerve. These results demonstrate that at least two types of peripheral glia (the unmyelinated Schwann cell and the satellite cell), in addition to the astrocyte, respond to some pathologic stimuli with an increased expression of GFAP. However, two other GFAP-positive structures, the Bergmann and radial glia, showed no significant changes in their immunostaining.

Animals↗

[Fundamental and clinical evaluations of ceftazidime in neonates].

Evaluations of ceftazidime (CAZ) in a few different categories were carried out in neonates. Single doses of 20 mg/kg of CAZ were administered to 8 neonates (day-age range: 1-26) and 3 infants (day-age range: 45-119) by bolus intravenous injection. Mean serum concentrations of CAZ at 15, 30 min., 1, 2, 4 hours and 6 hours were 51.6 +/- 9.2, 48.1 +/- 8.7, 47.9 +/- 7.8, 38.2 +/- 6.5, 20.2 +/- 4.0 micrograms/ml, and 15.3 +/- 5.8 micrograms/ml, respectively, in the neonates, and 51.1 +/- 10.3, 44.7 +/- 6.8, 35.5 +/- 4.1, 21.4 +/- 2.0, 8.6 +/- 1.0 micrograms/ml and 3.5 +/- 0.8 micrograms/ml, respectively, in the infants. Mean half-lives of CAZ in serum were 2.87 +/- 0.77 hours in the neonates and 1.39 +/- 0.10 hours in the infants, and mean urinary recovery rates in the first 6 hours were 60.5 +/- 16.0%, and 76.8 +/- 39.6% in the neonates and the infants, respectively. When individual differences are taken into consideration, no significant difference exists among 30-minute serum concentrations of neonates of different day-ages, and these concentrations were not significantly different from those in infants and older children. Half-lives of CAZ in sera decreased rapidly with the advances of the day-ages of the neonates, and the half-life at an age of 1-month should be similar to that in older children. The CAZ was administered to 2 cases of suspected sepsis, 7 of acute pneumonia, 1 of acute pyelonephritis, 1 of cellulitis, and 2 of idiopathic respiratory distress syndrome, and clinical efficacies were excellent in all the cases except for 2 cases excluded from the assessment. S. pyogenes (1), E. coli (1) and S. aureus (1) suspected as causative organisms were eradicated by the treatment with CAZ. Neither clinical adverse effects nor abnormal laboratory findings were observed in any case. From the above results, CAZ is considered to be an antibiotic with high efficacy and safety in the treatment of neonates.

Bacterial Infections↗

Bioimpedance measurement with respect to pulsatile pulmonary blood flow.

We used four-electrode electrical impedance plethysmography (IPG) to estimate regional pulmonary perfusion at three lung volumes, RV, FRC, and TLC. To define the region, the upright lung was divided into four equal sampling areas dorsally along the paravertebral space. The Kubicek formula was used to calculate pulmonary perfusion. Regional base resistance (Ro) decreased from the top to about 3/4 down the lung and then leveled off. The regional perfusion (Qz) showed an increase from the apex to about 3/4 down the lung and thereafter decreased toward the base, except at TLC. The regional distribution of the electrical derivative of resistance (dR/dt) resembled that of Qz because there was no statistically significant difference in ventricular ejection time or heart rate among studies. The value of the arithmetic sum of regional Ro was significantly larger than that of Ro for the total sampling field while the reverse was true for Qz. These discrepancies can be explained on the basis of the lead field theory applied to IPG. The regional perfusion gradient determined by IPG represents the pulsatile perfusion gradient in vivo because the outputs from the impedance analyzer are intimately linked to the pulse-synchronous pulsatile nature of pulmonary blood flow. Safe, simple, and noninvasive IPG can be used to study regional pulmonary perfusion in clinical situations, high altitude, or unusual environments.

Adult↗

[Fundamental and clinical studies on cefixime in pediatrics].

Bacteriological, pharmacokinetic, and clinical studies of cefixime (CFIX), a newly developed oral cephalosporin, was conducted in our pediatric department as outlined below. Bacteriology The prevalent MICs of CFIX by microbiological species, compared with those of the reference drugs, were detailed below. Against 16 strains of S. aureus, the MICs averaged 6.25 micrograms/ml, and were found to be nearly the same as the MICs of amoxicillin (AMPC) but higher than those of cephalexin (CEX) and cefaclor (CCL). For 4 strains of S. pyogenes, the MICs averaged 0.05 microgram/ml, and were higher than the MICs of AMPC but lower than those of CEX and CCL. Mean MICs of CFIX against other clinical isolates were lower than those of CEX, CCL, or AMPC; E. coli (20 strains), 3.13 micrograms/ml; K. pneumoniae (9), 0.10 microgram/ml; P. mirabilis (16), 0.025 microgram/ml; P. vulgaris (5), 0.10 microgram/ml; H. influenzae (11), 0.05 microgram/ml; and S. typhimurium (4), 0.10 microgram/ml. The MICs of CFIX against 10 strains of P. aeruginosa were distributed at and above 25 micrograms/ml, a range much lower than greater than or equal to 100 micrograms/ml for CEX, CCL, or AMPC. Pharmacokinetics The serum concentrations and urinary recovery were studied in 3 children ranging from age 7 to 13. They were given CFIX on empty stomach in 2 different single doses of 3 and 6 mg/kg in a cross-over design. Average serum CFIX concentrations were dose-dependent, as evidenced by the respective peak concentrations of 1.70 microgram/ml for a 3 mg/kg dosage and 2.72 micrograms/ml for 6 mg/kg, which were attained 4 hours after the administration of the drug. The average half-lives of CFIX in the serum were 3.09 hours and 3.11 hours, respectively, and the 12-hour serum concentrations were 0.32 microgram/ml and 0.77 microgram/ml, respectively, for the 2 different dose levels. The average 12-hour urinary recovery was 25.2% and 22.3%, respectively. Clinical study Clinical effectiveness, bacteriological effectiveness, and side effects were studied in 27 children with infection including 4 patients with acute pharyngitis, 13 with acute purulent tonsillitis, 5 with acute pneumonia, 3 with urinary tract infection, and 1 each with acute rhinitis and acute bronchitis. One child with acute pneumonia (Mycoplasma pneumonia) was excluded from the study. The therapeutic effectiveness was "excellent" in 21, "good" in 3, "fair" in 1, and "poor" in 1, with an effectiveness rate of 92.3%.(ABSTRACT TRUNCATED AT 400 WORDS)

Bacteria↗

The twitcher mouse: positive immunohistochemical staining of globoid cells with monoclonal antibody against Mac-1 antigen.

The expression of Mac-1 antigen (macrophage surface antigen) was studied by the immunoperoxidase method in the nervous system of the twitcher mouse (an authentic murine model of globoid cell leukodystrophy) from day 10 to day 39, to elucidate the origin of the globoid cells. Mac-1 positive cells were seen in peripheral nervous system (PNS) at all ages examined. The positive cells in central nervous system (CNS) showed staining characteristics similar to those in PNS, but in the CNS positive cells they appeared first at day 15 and increased significantly in older mice. These cells were always predominant in the white matter. There were few positive cells in the neural parenchyma of control mice before day 10 but none thereafter. The occurrence and the preferential distribution indicate that it is quite likely that Mac-1 positive cells in the twitcher mouse represent globoid cells. Twitcher mice which were previously given colloidal carbon intravenously, had some Mac-1 positive cells which contained carbon particles both in the CNS and PNS. These facts indicate that globoid cells are the cells of monocytic lineage and at least some of them are derived from blood monocytes.

Animals↗

Preparation of human salivary alpha-amylase specific monoclonal antibody.

A mouse hybridoma cell line which produced an anti-human salivary alpha-amylase monoclonal antibody was obtained by fusion between mouse spleen cells immunized with human salivary alpha-amylase and mouse myeloma cells, followed by screening the hybridoma cells by enzyme-linked immunosorbent assay. The hybridoma cell line (27-4-1) secreted IgG. The monoclonal antibody produced by the hybridoma showed no inhibitory effect on the activity of human salivary alpha-amylase. The specificity and reactivity of this monoclonal antibody were examined by determining the activities of human salivary and pancreatic alpha-amylases bound to the monoclonal antibody immobilized on polystyrene balls or by enzyme immunoassay with the monoclonal antibody conjugated with beta-D-galactosidase. The results revealed that the monoclonal antibody produced by the hybridoma cell line was specific for salivary alpha-amylase and absolutely unreactive to pancreatic alpha-amylase.

Antibodies, Monoclonal↗

The role of airflow in mucous transport in the trachea.

The role of airflow in mucous transport in the respiratory tract was studied. Seven mongrel dogs were tracheostomised at the caudal end of the neck, and the following two procedures were performed. In procedure (1), a small radiopaque plastic disc was placed on the mucous membrane of the right side wall of the trachea through the tracheostoma, which was then closed to let the dog breathe through the normal respiratory tract. Roentgenograms of the trachea were taken three times at 5-min intervals. Procedure (2) was designed to eliminate airflow from around the disc. A canula was placed in the trachea through the tracheostoma to bypass airflow, and the disc was placed on the mucous membrane slightly more proximal than the cannula. The transport rate was 11.1 +/- 4.1 mm/min (mean +/- S.D.) in procedure (1) and 5.4 +/- 2.7 mm/min in procedure (2), which showed a significant difference. The present results seem to indicate an important role of airflow in mucous transport in the trachea.

Animals↗

[A case report of a double cancer of the ureter and stomach].

A 63-year-old man complained of hunger epigastralgia. X-ray and endoscopic examination demonstrated Borrmann II type gastric carcinoma. Radical gastrectomy was performed on October 20, 1982. The histological findings revealed moderately differentiated tubular adenocarcinoma. In May 1983, right hydronephrosis was recognized by ultrasonography. A papillary tumor was visualized in the right ureter in retrograde pyelography, and percutaneous transrenal urinary tract drainage was performed. Cytological findings revealed class V. Total nephro-uretectomy was performed on June 16, 1983. The histological findings revealed transitional cell carcinoma.

Carcinoma, Intraductal, Noninfiltrating↗

[Experimental and clinical studies on BRL 25000 (clavulanic acid-amoxicillin) in the pediatric field].

Fundamental and clinical studies on BRL 25000 granules were carried out in the pediatric field. BRL 25000 is a formulation comprising 1 part of clavulanic acid (CVA) and 2 parts of amoxicillin (AMPC). The MICs of BRL 25000 and AMPC were assessed against 24 clinically isolated strains of S. aureus (including 23 beta-lactamase producing strains), 22 S. pyogenes, 20 E. coli (8 beta-lactamase producing strains), 24 K. pneumoniae (24 beta-lactamase producing strains), 20 H. influenzae (6 beta-lactamase producing strains). BRL 25000 showed MIC80 (cumulatively 80% of strains were inhibited) at 6.25 micrograms/ml against S. aureus, less than or equal to 0.10 micrograms/ml against inst S. pyogenes, 12.5 micrograms/ml against E. coli, 6.25 micrograms/ml against K. pneumoniae and 0.39 micrograms/ml against H. influenzae. BRL 25000 showed no improvement in MIC terms against beta-lactamase nonproducing strains compared with AMPC. However, BRL 25000 was markedly more effective against beta-lactamase producing strains. Thus BRL 25000 was up to 8 fold more active against S. aureus, 2 to 64 fold against E. coli, 4 to 128 fold against K. pneumoniae, 4 to 16 fold against H. influenzae than AMPC. Following oral administration of BRL 25000 granules (at a dose level of 12.5 mg/kg) to 2 children aged 9 and 11 years, the mean peak serum concentrations of AMPC and CVA were 8.33 +/- 2.43 micrograms/ml and 4.44 +/- 1.65 micrograms/ml respectively 1 hour after dosing. The half-lives of AMPC and CVA were 1.35 +/- 0.42 hours and 0.91 +/- 0.05 hour, respectively. The urinary excretion was 48.21 +/- 3.83% for AMPC and 16.90 +/- 7.06% for CVA in the first 6 hours after administration. In clinical studies, 23 pediatric patients aged 2 months to 12 years with bacterial infections were treated with BRL 25000 granules and the clinical effectiveness, bacteriological response and side effects were evaluated. The clinical response was assessed in 23 cases, 3 with acute rhinitis, 6 with acute purulent tonsillitis, 5 with acute bronchitis, 4 with acute pneumonia, 3 with impetigo, 1 with furunculosis and 1 with periproctal abscess. Results were excellent in 13 cases, good in 7, fair in 3 and hence the efficacy rate (excellent and good cases) was 87.0% (20/23). In particular the clinical response in 9 cases with infections due to beta-lactamase producing organisms was excellent in 6, good in 2, fair in 1 and the efficacy rate was 88.9% (8/9).(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗

[Fundamental and clinical studies on aspoxicillin in the pediatric field].

Fundamental and clinical studies of aspoxicillin (ASPC, TA-058), a new penicillin antibiotic, were performed in pediatric field. Antimicrobial activity MIC of ASPC was compared with that of piperacillin (PIPC), ampicillin (ABPC) and carbenicillin (CBPC) for clinical isolates of S. aureus (24 strains), S. pyogenes (22 strains), H. influenzae (18 strains), E. coli (21 strains) and K. pneumoniae (23 strains). MIC of ASPC against S. pyogenes was distributed in less than 0.39 microgram/ml and this numerical value of MIC was very superior. MIC distributions of ASPC against S. aureus, H. influenzae and E. coli had 2 peaks respectively. It was presumed that the results are due to an existence of beta-lactamase producing strains. The sensitive strains in those were distributed in less than 1.56-12.5, less than or equal to 0.10 and 0.78-3.13 micrograms/ml, respectively, and those numerical value of MIC was superior. While against K. pneumoniae, all strains were distributed in more than 12.5 micrograms/ml and the antimicrobial activity of ASPC was very inferior. ASPC was as active as PIPC and ABPC against S. pyogenes, but more active then CBPC, ASPC was less active against S. aureus than PIPC and ABPC, but more active than CBPC. And ASPC was less active against H. influenzae and E. coli than PIPC, but more active than ABPC and CBPC. Against K. pneumoniae, strains that showed somewhat low numerical value of MIC at only PIPC were observed, but antimicrobial activities of ABPC and CBPC, as well as ASPC were very inferior. Absorption and excretion Serum level and urinary excretion of ASPC in 6 pediatric patients of 4 months to 12 years of age after one shot intravenous injection of 20 mg/kg were examined. The serum mean levels were 51.7 micrograms/ml at 1/4 hour, 38.2 micrograms/ml at 1/2 hour, 22.9 micrograms/ml at 1 hour, 3.0 micrograms/ml at 4 hours and 1.0 microgram/ml at 6 hours after injection, respectively. The mean half-life of serum level was 1.03 hours. The mean urinary levels were 4,646 micrograms/ml for 0-2 hours, 1,773 micrograms/ml for 2-4 hours and 299 micrograms/ml for 4-6 hours. The mean urinary recovery rate within 6 hours after injection was 64.7%. Clinical studies In order to evaluate clinical response, bacteriological response and side effects, ASPC was applied to 28 cases, i.e., 5 cases of acute purulent tonsillitis, 2 cases of acute purulent otitis media, 2 cases of acute bronchitis and 19 cases of acute pneumonia.(ABSTRACT TRUNCATED AT 400 WORDS)

Amoxicillin↗