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F Hayakawa

Publications and source records attributed to F Hayakawa.

At least 91 records · Page 5Linked to original sources

[Laboratory and clinical studies on panipenem/betamipron in the field of pediatrics].

Laboratory and clinical studies on panipenem/betamipron (PAPM/BP), a new carbapenem antibiotic, were carried out in the field of pediatrics and the following results were obtained. 1. The antibacterial activities of panipenam (PAPM) against clinically isolated organisms in our department were high overall. 2. After 30 minutes intravenous infusion of PAPM/BP at a dose of 10 mg/10 mg/kg in 1 and of 20 mg/20 mg/kg in 2 children, peak plasma levels of PAPM ranged from 33.21 to 75.66 micrograms/ml at the end of the infusion. The half-lives were 0.81 to 0.93 hours. The cumulative urinary recovery rates in the first 6 hours after the start of drip infusion ranged from 10.7 to 40.4%. 3. PAPM/BP was administered to 16 pediatric patients with various infections. The clinical and bacteriological efficacy rates were both 100%. 4. No side effects were observed. Abnormal laboratory test results were also mild; slight elevation of GOT, GOT/GPT and eosinophylia in 1 each and thrombocytosis in 2.

Age Factors↗

[Laboratory and clinical studies on meropenem in pediatrics].

Laboratory and clinical studies on meropenem (MEPM), a new carbapenem antibiotic, were carried out in the field of pediatrics. The results obtained are summarized below. 1. The antibacterial activities of MEPM against clinically isolated organisms in our department were generally high. 2. After 30 minutes intravenous drip infusion of MEPM at a dose of 20 mg/kg to 2 children, the mean peak plasma level of MEPM was 32.7 micrograms/ml at the end of infusion with a mean half-life of 1.45 hours. The mean cumulative urinary recovery rate in the first 6 hours after infusion was 43.6%. 3. Fifteen patients with various bacterial infections were treated with MEPM. The clinical efficacy rate was 100% and the bacteriological efficacy rate was 95.2%. 4. No side effects were observed except in 1 case of mild diarrhea. Some abnormal laboratory test results were obtained, but they were mild with slight elevations of GOT and GPT in 2 cases.

Bacteria↗

[Evaluation of serial EEG recordings and auditory brainstem responses in the early preterm infants].

EEGs were recorded serially throughout the neonatal period and auditory brainstem responses (ABRs) in the late neonatal period in 105 preterm infants with the gestational age of less than 33 weeks and birth weights of less than 1,750g in order to study the relation between abnormal findings and neurological outcome. A study of serial EEG recordings revealed that a disorganized pattern following severe depression of background EEG activities was closely associated with deep white matter injuries detected by ultrasonography and that infants showing such features are likely to suffer from cerebral palsy. On the other hand, a dysmature pattern was often observed following prolonged mild depression, although no abnormalities were apparent on ultrasonography. This EEG pattern was more often associated with mental impairment. Any findings of ABRs were not associated with adverse outcome. We conclude that serial EEG recordings during the neonatal period in preterm infants are useful in clarifying the extent and nature of brain injury as well as future developmental problems.

Brain Diseases↗

Relationship between zinc and cellulose intakes in growing rats.

We have studied the effect of cellulose on the intestinal absorption of zinc and its metabolism with weanling male rats. Experimental diets were cellulose (5, 8 or 20%) and noncellulose containing normal zinc (AIN-76 mineral mix., 3.0 mg%) or high zinc (10 times of normal, 30 mg%). Weanling rats fed on these diets ad libitum for 16-42 days. There were no significant differences between noncellulose-feeding and cellulose-feeding groups in body weight gain or protein and DNA concentrations in the liver. The inhibitory effect of 20% cellulose on zinc absorption was observed in the long term experiment, as the concentrations of plasma zinc of the group receiving 20% cellulose were decreased significantly more than that of noncellulose-feeding group.

Animals↗

[Laboratory and clinical studies on cefdinir in pediatric field].

Clinical trials of cefdinir (CFDN) in pediatric infections were carried out. Results are summarized as follows. 1. Mean half-lives of CFDN in serum in children when administered on an empty stomach were 1.24 hours (3 mg/kg per os) and 1.85 hours (6 mg/kg per os). 2. Mean 8 hour urinary excretion rates of CFDN were 19.0% (3 mg/kg/per os) and 10.5% (6 mg/kg per os). 3. CFDN was administered to 28 children with various infections: 12 patients with tonsillitis, 8 with bronchitis, 2 with pneumonia, 4 with urinary tract infections, 1 staphylococcal scalded skin syndrome and 1 with impetigo. The overall efficacy rate was 89.3%. 4. Diarrhea was noted in 1 patient. Abnormal laboratory test values encountered were eosinophilia in 2 patients, thrombocytosis in 1.

Adolescent↗

[Bacteriological and clinical studies on norfloxacin in the field of pediatrics].

Bacteriological and clinical studies on norfloxacin (NFLX) were carried out in the field of pediatrics, and the results obtained are summarized as follows: 1. The MICs of NFLX against clinically isolated organisms were determined to compare with MICs of nalidixic acid, amoxicillin, cefaclor, erythromycin and fosfomycin. NFLX had low MICs against both Gram-positive and Gram-negative bacteria and, particularly, showed higher antimicrobial activity to Escherichia coli, Salmonella sp., Klebsiella pneumoniae, Pseudomonas aeruginosa, Haemophilus influenzae and Campylobacter jejuni than any other drugs tested. 2. Seventeen pediatric patients (11 cases of enteritis, 4 cases of urinary tract infections, 1 case of tonsillitis and 1 case of pyoderma) were treated orally with NFLX in daily doses ranging from 3.1 to 16.7 mg/kg t.i.d. for 6-14 days. Rates of clinical effectiveness and bacterial elimination were 94.1% and 58.8%, respectively. 3. None of the treated children showed clinical symptoms indicating the occurrence of side effects nor abnormal laboratory findings except 1 patient with eosinophilia. These results indicate the usefulness of NFLX in the treatment of bacterial infections in the pediatric field.

Administration, Oral↗

[Laboratory and clinical studies on clarithromycin in the field of pediatrics].

Laboratory and clinical studies on clarithromycin (TE-031, A-56268), a new macrolide antibiotic, were carried out in the field of pediatrics. The results obtained are summarized as follows: 1. Serum concentrations, urinary concentrations and urinary recovery rates were determined upon oral administration on fasting of TE-031 at doses of 5 mg/kg granules in 1 case and tablets in 2 cases, and 10 mg/kg granules in 1 and 15 mg/kg granules in 1. Peak serum levels were obtained at 30 minutes in 2 cases, at 1 hour in 2 cases and at 2 hours in 1 case after administration of the drug with a range of 2.29-7.10 micrograms/ml with half-lives of 2.2-7.5 hours. Urinary recovery rates in 6 hours after administration ranged from 7.1-34.5%. 2. MICs of TE-031 against 49 clinical isolates (Streptococcus pyogenes 5 strains, Streptococcus pneumoniae 9, Staphylococcus aureus 3, Branhamella catarrhalis 4, Haemophilus influenzae 14, Haemophilus parainfluenzae 7, and Campylobacter jejuni 7) were compared with those of josamycin (JM), erythromycin (EM), and ampicillin (ABPC). The antibacterial activity of TE-031 was superior to those of JM and equal to those of EM. 3. Fifty-five pediatric patients with acute infectious diseases (scarlet fever 3 cases, pharyngitis and tonsillitis 15, pertussis 2, pneumonia 10, bronchitis 14, Campylobacter enteritis 11) were treated with TE-031 at daily doses of 10-35 mg/kg t.i.d. as a rule. The efficacy rates were 96% clinically and 72% bacteriologically. 4. Side effects or abnormal laboratory test values were not observed. 5. None of children refused TE-031.

Adolescent↗

[Bacteriological, pharmacokinetic and clinical studies on cefpodoxime proxetil in the pediatric field].

Bacteriological, pharmacokinetic and clinical studies on cefpodoxime proxetil (CPDX-PR, CS-807), a new oral cephem antibiotic, were carried out in the field of pediatrics. The results obtained are summarized as follows. 1. Antibacterial activities of R-3746 (Na-salt of cefpodoxime (CPDX] against clinically isolated strains of Streptococcus pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, Enterococcus faecalis, Branhamella catarrhalis, Escherichia coli, Proteus mirabilis and Haemophilus influenzae were compared with those of cefaclor, cephalexin and cefadroxil. R-3746 is superior to other antibiotics against S. pneumoniae, S. pyogenes, B. catarrhalis and Gram-negative rods. 2. Serum concentrations of CPDX after administration of CPDX-PR at doses of 3 mg/kg (fasting), 6 mg/kg (non-fasting) and 6 mg/kg (fasting) were determined. Mean AUC (area under curve)'s of CPDX obtained were 9.60, 31.35 and 17.89 micrograms.hr/ml, respectively for the 3 dosages. The mean half-lives of CPDX were 3.35, 1.88 and 1.76 hours, respectively. The mean urinary recovery rate within 8 hours after administration of CPDX-PR at a dose of 3 mg/kg (fasting) was 39.2%. 3. CPDX-PR was administered to 37 pediatric patients with various bacterial infections (pyelonephritis 9, cystitis 4, pneumonia 7, acute bronchitis 3, otitis media 2, tonsillitis 10, subcutaneous abscess 1 and purulent lymphadenitis 1). The overall clinical efficacy rate was 91.9% and the overall bacteriological eradication rate was also 91.9%. 4. No adverse reactions were observed. Abnormal laboratory findings were moderate, eosinophilia in 2 and slight elevation of GOT and GPT in 1. The taste and the odor of the CPDX-PR preparation was sufficiently tolerable. From the above results we have concluded that CPDX-PR is a useful oral antibiotic in the treatment of bacterial infections in children.

Bacteria↗

[Pharmacokinetic, bacteriological and clinical studies on sulbactam/ampicillin in pediatric field].

Clinical trials were carried out on the use of sulbactam/ampicillin (SBT/ABPC) (combination rate of 1:2) in pediatric infections. Results were as follows: 1. The mean half-lives of SBT and ABPC in the serum following intravenous injection of SBT/ABPC were about 1.05 and 0.90 hours, respectively. 2. The mean urinary excretions of SBT and ABPC in 6 hours after intravenous injection of SBT/ABPC were 71.2% and 62.2%, respectively. 3. SBT/ABPC was administered to 23 pediatric patients with various infections: 17 patients with pneumonia, 3 with tonsillitis, 2 with urinary tract infection and 1 with cervical lymphadenitis. The overall efficacy rate was 95.7%. In particular, 2 urinary tract infections caused by highly beta-lactamase producing Escherichia coli were improved by the treatment with SBT/ABPC. 4. No adverse reactions were observed except 2 cases of mild diarrhea. Abnormal laboratory test values included thrombocytosis in 4 and slight elevation of GOT and GPT in 1, but they were transient.

Age Factors↗

[Laboratory and clinical studies of cefodizime in pediatric field].

Clinical trials of cefodizime (CDZM, THR-221) were carried out in pediatric infection. Results are summarized as follows. 1. The mean half-life of CDZM in the serum following intravenous injection of CDZM (20 mg/kg) was about 2.06 hours. 2. The mean urinary excretion rate of CDZM within 8 hours after intravenous injection of CDZM was 60.1%. 3. CDZM was administrated to 19 pediatric patients with various infections; 9 cases of pneumonia, 3 bronchitis, 1 cervical lymphadenitis, 2 tonsillitis and 4 urinary tract infections. The overall efficacy rate was 94.7%. 4. No adverse reactions were observed. Abnormal laboratory test values found were thrombocytosis in 2, slight elevation of GOT and GPT in 1 and eosinophilia in 1 patient.

Age Factors↗

[Laboratory and clinical studies on cefteram pivoxil in the field of pediatrics].

Laboratory and clinical studies on cefteram pivoxil(cefteram) a new cephem antibiotic, were carried out in the field of pediatrics. The results obtained are summarized as follows: 1. Serum concentrations, urinary concentrations and urinary recovery rates of cefteram (CFTM) were determined upon oral administration after meal of cefteram pivoxil (CFTM-PI) at doses of 3 mg/kg granules in 2 cases and 6 mg/kg granules in 2. Peak serum levels of CFTM were obtained at 3 hours in 2 cases and 4 hours in 2 cases after administration of the drug with a range of 0.74-2.2 micrograms/ml with half-lives of 0.77-3.62 hours. Urinary recovery rates in 8 hours after administration ranged from 9.6-23.0%. 2. MICs of CFTM against 22 clinical isolates (Streptococcus pyogenes 4 strains, Streptococcus pneumoniae 4, Staphylococcus aureus 2, Branhamella catarrhalis 1, Haemophilus influenzae 8, Haemophilus parainfluenzae 1, and Escherichia coli 2) were compared with those of cefaclor (CCL), cephalexin (CEX), and ampicillin (ABPC). The antibacterial activity of CFTM was superior to those of CCL and CEX, and was superior against Gram-negative rods and equal against Gram-positive cocci to those of ABPC. 3. Twenty-six pediatric patients with acute infectious diseases (scarlet fever 3 cases, tonsillitis 7, epiglottitis 1, bronchitis 5, pneumonia 5, urinary tract infection 3, cervical lymphadenitis 2) were treated with CFTM-PI at daily doses of 9.3-15.3 mg/kg t.i.d. as a rule. The efficacy rates were 100% clinically and 70% bacteriologically. 4. Side effects or abnormal laboratory test values were not observed except for an increased platelet count in 1 case.

Absorption↗

Development of the monosynaptic reflex pathway in the human spinal cord.

Development of the monosynaptic reflex pathway of the spinal cord was investigated in 96 neurologically normal infants with ages ranging from 25 weeks in postconceptional age (PCA) to 24 months after full-term delivery (PDA) by examining H-reflexes from the triceps surae and hypothenar muscles in terms of their incidence, latency and maximal size in reference to the maximal M-wave. The triceps H-reflex was evoked in all cases, and the latency was longest (26 ms) in the youngest case of 25 weeks (PCA). It gradually shortened until full-term gestation, reaching the shortest value of 17 ms (mean). The H-reflex size initially increased until full-term gestation, reaching the maximum value of 70% and then reducing gradually to the plateau level of about 30% at 12 months (PDA). The hypothenar H-reflex could not be elicited until 32 weeks (PCA). The time course of changes in its latency and size was similar to those of the triceps H-reflex, except that it could not be elicited after 12 months (PDA). Thus, the monosynaptic reflex pathway is already functioning at the age of 25 weeks (PCA) in man. The significance of the systematic change in latency and excitability of the H-reflex with age is discussed.

Aging↗

[Laboratory and clinical studies of rokitamycin dry syrup in the field of pediatrics].

Laboratory and clinical studies on rokitamycin (RKM) dry syrup, a new macrolide antibiotic, were carried out in the field of pediatrics. The results are summarized as follows. 1. Plasma concentrations and urinary recovery rates after oral administration on fasting of RKM dry syrup at doses of 10 mg/kg and 20 mg/kg to 2 and 1 cases, respectively, were determined. Peak plasma levels were obtained in 30 minutes after administration of both dosages with half-lives of 1.5 to 2.2 hours. A clear-cut dose response was observed. Urinary recovery rates in the first 6 hours after administration ranged from 1.75 to 2.26%. 2. The MICs of RKM against 80 clinical isolates (Streptococcus pyogenes 9, Streptococcus pneumoniae 14, Branhamella catarrhalis 4, Haemophilus influenzae 27, Haemophilus parainfluenzae 9, Haemophilus haemolyticus 2, Haemophilus parahaemolyticus 14 and Campylobacter jejuni 1) were compared with MICs of midecamycin acetate (MOM), josamycin (JM) and erythromycin (EM). The antibacterial activity of RKM was superior to those of MOM and JM and slightly inferior to that of EM. 3. Twenty-eight pediatric patients with acute infectious diseases (acute tonsillitis 4, streptococcal infection 4, acute bronchitis 9, pneumonia 4, mycoplasmal pneumonia 2 and Campylobacter enteritis 5) were treated with RKM dry syrup at a daily dose of 12-42.9 mg/kg t.i.d. as a rule. Efficacy rates were 92.9% clinically and 58.6% bacteriologically. 4. No adverse reactions were observed. Abnormal laboratory findings were mild; thrombocytosis in 2 and eosinophilia in 1. 5. The taste and the odor of RKM dry syrup preparation were sufficiently tolerable for the pediatric patients to accept it.

Administration, Oral↗

[Pharmacokinetic, bacteriological and clinical studies of sultamicillin fine granule in pediatric field].

Pharmacokinetic, bacteriological and clinical studies on sultamicillin (SBTPC) fine granule were carried out in the field of pediatrics. The results obtained are summarized as follows. 1. Antibacterial activities of SBTPC against clinically isolated strains of Haemophilus influenzae, Haemophilus parainfluenzae, Streptococcus pneumoniae, Streptococcus pyogenes, Streptococcus agalactiae, Staphylococcus aureus, Branhamella catarrhalis, and Escherichia coli were compared with those of ampicillin (ABPC). SBTPC was superior to ABPC especially against beta-lactamase producing H. influenzae, E. coli, S. aureus, and B. catarrhalis. 2. Serum concentrations and urinary excretion rates of sulbactam (SBT) and ABPC after administration of SBTPC fine granule at a dose level of 10 mg/kg in 2 cases were determined. Mean half-lives of SBT and ABPC in the serum following oral administration were about 1.33 and 1.61 hours respectively. Mean urinary recovery rates of SBT and ABPC in 6 hours after oral administration at a dose of 10 mg/kg were 58.7% and 49.6% respectively. 3. SBTPC fine granule was administered to 20 pediatric patients with various bacterial infections (pneumonia 8 cases, bronchitis 2, pharyngitis 2, tonsillitis 4, subcutaneous abscess 1 and urinary tract infection 3). The overall clinical efficacy rate was 100% and the overall bacteriological eradication rate was 75%. 4. No adverse reactions were observed except 1 case of loose stool. No abnormal laboratory test values were observed. These results indicate the usefulness of SBTPC fine granule in the treatment of bacterial infections in children.

Adolescent↗

Fz theta/alpha bursts: a transient EEG pattern in healthy newborns.

We named transient activity recorded from midline frontal area 'Fz theta/alpha bursts' and investigated their characteristics and clinical significance. Polygraphic examinations were carried out on a total of 155 infants from 35 to 46 weeks of postconceptional age. Fz theta/alpha bursts were recorded in 40 (36%) of 111 infants without neurological problems. Especially these bursts were found in 33 (55%) of 60 infants at 38-42 weeks of postconceptional age. They occurred in pre-term as well as in full-term newborns. Three hundred and sixty-two Fz theta/alpha bursts were recorded from 40 infants without neurological problems. Ninety-one percent of them were found in quiet sleep, and others in indeterminate sleep. None of them were recorded in active sleep. Fz theta/alpha bursts did not occur synchronously with frontal or temporal sharp transients. The incidence of Fz theta/alpha bursts in infants with abnormal neurological signs was lower than in control infants (4/44 vs. 37/73; P less than 0.01). The bursts were not detected in EEGs with moderately or more severely depressed background. One hundred and thirty-five infants were followed up for more than 12 months. Fz theta/alpha bursts were recorded in 38 (35%) of 109 infants with normal outcome, and in only 1 (4%) of 26 infants with abnormal outcome. Our results indicated that Fz theta/alpha bursts were of normal EEG components without pathological significance.

Alpha Rhythm↗

Neurophysiological and neuroradiological features preceding infantile spasms.

Neonatal EEG, cerebral evoked potentials, CT scan findings and their evolution were investigated in 42 neonates who eventually developed the West syndrome. In infants with perinatal hypoxia, the EEG displayed most often marked or maximal depression in the first week of life. The highly abnormal initial EEG improved progressively with time. The most frequent findings in early infancy was discontinuous tracing and persistent alternating tracing at 1-2 months, and absent sigma rhythms at 3-4 months. The VEP, AEP and CT scan also showed findings suggesting severe degree of brain damage. In infants with meningitis, the initial EEG was less depressed but the EEG abnormality persisted or worsened. In infants with prenatal causes the neonatal EEG was variable, ranging from a normal background EEG to specific abnormalities. The evolution of paroxysmal abnormalities was similar in all groups. There were no epileptiform discharges in early months. The appearance of hypsarrhythmia was preceded by focal and then multifocal spike or sharp wave discharges.

Electroencephalography↗

[Bacteriological and clinical studies of flomoxef in the field of pediatrics].

Bacteriological and clinical studies with flomoxef (FMOX, 6315-S), a new oxacephem antibiotic, were carried out in the field of pediatrics and the results obtained are summarized as follows: 1. The antimicrobial activity of FMOX against clinically isolated organisms was determined. FMOX had a good antimicrobial activity against Streptococcus pneumoniae, Escherichia coli, Haemophilus influenzae and especially against Staphylococcus aureus (including methicillin resistant S. aureus). 2. Mean serum concentrations of FMOX following intravenous bolus injection of 20 and 40 mg/kg (in 7 and 4 cases, respectively) were 35.3 and 77.7 micrograms/ml at 15 minutes after administration with mean serum half-lives (T1/2) of 0.75 and 0.95 hours and mean urinary recovery rates up to 6 hours after administration were 71.9 and 65.1%, respectively. 3. Twenty-five pediatric patients (19 cases of pneumonia, 1 case of pyothorax and 5 cases of urinary tract infection) were treated with FMOX in doses ranging from 50 to 138 mg/kg divided into 3 or 4 times a day. The rate of clinical effectiveness was 100% and the bacterial elimination rate was 90.6%. 4. No adverse reactions were observed. Abnormal laboratory findings were eosinophilia in 1, thrombocytosis in 2 and slight elevations of GOT and GPT in 3 patients. These results indicate the usefulness and the safety of FMOX in the treatment of bacterial infections in the pediatric field.

Age Factors↗

[Fundamental and clinical studies on cefuzonam in the field of pediatrics].

Fundamental and clinical studies on cefuzonam (L-105, CZON), a newly semisynthesized cephem antibiotic, were carried out in the field of pediatrics and the following results were obtained. Antibacterial activities of CZON against clinically isolated strains of Staphylococcus aureus, S. epidermidis, Streptococcus pneumoniae, S. pyogenes, Escherichia coli, Klebsiella pneumoniae, Haemophilus parainfluenzae and H. influenzae were compared with those of cefmenoxime (CMX), latamoxef (LMOX), cefoperazone (CPZ), cefmetazole (CMZ), cefotiam (CTM) and cefazolin (CEZ). CZON was nearly as active as CEZ against S. aureus and S. epidermidis and superior to other antibiotics against other Gram-positive cocci. Against Gram-negative rods, CZON was as active as CMX and superior to other 5 antibiotics compared. Serum concentrations and urinary excretion rates after intravenous bolus injection of CZON at doses of 10 mg/kg, 20 mg/kg and 40 mg/kg for 5 minutes in 1, 5 and 4 cases, respectively, were determined. Mean serum concentrations of CZON at these dose levels were 11.0, 43.8 and 111.5 micrograms/ml at 15 minutes, 2.4, 10.3 and 30.3 micrograms/ml at 1 hour and 0.17, 0.72 and 1.28 micrograms/ml at 4 hours, with serum half-lives of 1.79, 0.88 and 1.19 hours, respectively. Mean cumulative urinary excretion rates within 6 hours after administration were 47.9, 56.3 and 40.3%, respectively. Thirty-four pediatric patients with various bacterial infections (tonsillitis 2, acute bronchitis 1, pneumonia 14, pyothorax 1, sepsis 1, suppurative lymphadenitis 1, UTI 13 and enteritis 1) were treated with CZON at a daily dose of 40-94 mg/kg t.i.d. or q.i.d.. The overall clinical efficacy rate was 94.1%. No adverse reactions were observed except 2 cases with mild diarrhea. Abnormal laboratory findings were also mild; slight elevation of GOT and GPT in 2, eosinophilia in 1 and thrombocytosis in 1. These results clearly indicate the usefulness of CZON in the treatment of bacterial infections in children.

Age Factors↗