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H Sakata

Publications and source records attributed to H Sakata.

At least 163 records · Page 9Linked to original sources
PubMed1990

[Neurons in monkey parietal association cortex sensitive to depth movement].

We recorded neurons sensitive to depth movement from the inferior parietal lobule (area 7a) of alert behaving monkeys, and studied their response to changing sizes of retinal images and to changing binocular disparity. The size of the stimulus was changed by changing both the height and width of a slit in the same way, and the disparity change was produced by varying distances between a pair of polarized stimuli on a screen. Of 227 purely visual neurons recorded from 11 hemispheres of 7 monkeys, 32 neurons responded to the change of either the size or disparity, or both. Some of the neurons sensitive to size change could be activated by changing length on only one axis, but the optimal stimulus for most of them was a uniform change of size in all directions. The neurons sensitive to disparity change responded weakly to monocular stimuli, but showed clear selectivity in the direction of change of disparity when binocular stimuli were applied. We also found a group of depth movement sensitive neurons that responded maximally to the simultaneous change of size and disparity. This type of neurons may signal real depth movement by integrating the signals of size change and disparity change.

Animals↗
PubMed1990

[Pharmacokinetics and clinical studies on aztreonam in neonates and premature infants (the first report). Study on effectiveness and safety in mono-therapy with aztreonam. A study of aztreonam in the Perinatal Co-research Group].

Pharmacokinetics and clinical study of aztreonam (AZT) in neonates and premature infants were conducted with the following results: 1. Pharmacokinetics (1) Serum concentrations of AZT at 30 minutes after one-shot intravenous injection of 10 mg/kg and 20 mg/kg to neonates including premature infants were 20.6-26.6 micrograms/ml and 38.5-46.4 micrograms/ml, respectively, and decreased thereafter. A dose response was observed in the serum concentrations with administration of AZT 10 mg/kg and 20 mg/kg. (2) Serum half-lives (T1/2) tended to be shorter in both mature and premature infants as their day-ages increased and T1/2 tended to be prolonged in premature infants compared with mature infants. (3) Changes in serum concentration upon one-hour intravenous drip infusion of AZT 20 mg/kg were very similar to those upon one-shot intravenous injection. (4) Urinary excretions in the first 6 hours after one-shot intravenous injection of AZT 10 mg/kg or 20 mg/kg tended to increase in mature infants as they grew and showed excretion rate of 26.2-54.3% but those in premature infants did not show any specific tendency with rate of 17.5-45.1%. Urinary excretions upon intravenous drip-infusion showed a tendency very similar to those upon intravenous injection. 2. Clinical studies (1) Clinically evaluable cases of AZT treatment were 88 cases (91 diseases), in which pathogenic organisms were identified in 56 cases (Group A), i.e., sepsis 9, purulent meningitis 2, pneumonia 8, urinary tract infection (UTI) 33 and others. Total efficacy rate was 98.2% including "excellent" (39), "good" (16) and "fair" (1). Number of cases in which pathogenic organisms were unknown (Group B) was 11, i.e., suspected sepsis (4), pneumonia (3) and intrauterine infection (4) and the efficacy rate was 100% with "excellent" (4) and "good" (7). Thus, both group A and B showed excellent results. AZT was also given to 24 cases for prophylaxis and all the cases showed prophylactic effect of AZT.4+ Bacteriologically AZT was deemed effective in 53 cases out of 56 (Group A) with identified pathogens "eradicated" and "unchanged" (2), thus the bacterial eradication rate was 96.2%. (3) A minor degree of loose feces was observed in 1 (1.3%) of 80 cases as a side effect. Abnormal laboratory test values found were eosinophilia (3 cases), elevation of GOT and GPT (2), platelet-increase (1), elevation of GOT (1), and thrombocytopenia.elevation of GOT.GPT.LDH (1). Every one of these was of a minor degree and transient. From the above pharmacokinetics and clinical results, standard dosage of AZT to neonates and premature infants should be in a unit dose of 20 mg/kg, twice daily to those with ages between 0 and 3 days, and 2 to 3 times daily to those with ages 4 days and above, by intravenous injection or intravenous drip infusion.

Age Factors↗
PubMed1990

[Pharmacokinetics and clinical studies on aztreonam in neonates and premature infants (the second report). Study on effectiveness and safety in combination therapy using aztreonam and ampicillin. A study of aztreonam in the Perinatal Co-research Group].

Pharmacokinetics and clinical effects were studied in a combination therapy with aztreonam (AZT) and ampicillin (ABPC) in neonates and premature infants. The results obtained are summarized as follows. 1. Pharmacokinetics (1) Average serum concentrations at 30 minutes after one-shot intravenous injection of AZT 20 mg/kg and ABPC 25 mg/kg to a 4-7 days age-group of neonates were 41.3 (AZT) and 30.5 (ABPC) micrograms/ml, respectively. They gradually decreased to 14.7 and 2.7 micrograms/ml at 6 hours after the administration, but the concentration of AZT was always higher than that of ABPC. (2) Serum half-lives (T1/2) in the 4-7 days age-group were 3.61 hours for AZT and 1.42 hours for ABPC, thus T1/2 of AZT was longer. However, T1/2 of AZT was scarcely affected in the concomitant administration of ABPC. (3) Urinary excretion of AZT in the concomitant administration to the 4-7 days age-group was 52.7%, which was the same or a little higher comparing to that in AZT alone administration. 2. Clinical studies (1) AZT and ABPC were concomitantly administered to 160 cases and 133 cases were evaluated for efficacy. Pathogenic organisms were identified in 29 cases (Group A) and the efficacy rate was 86.2% (25/29). The number of cases in which pathogenic organisms were not identified (Group B) was 50 and in this group, the efficacy rate was excellent, 94.0% (47/50). AZT and ABPC were concomitantly administered to 54 cases for prophylaxis and in all the cases the administrations showed prophylactic effect. (2) Bacterial changes were confirmed in 21 of the 29 cases in which pathogenic organisms were identified initially and all of these 21 cases showed bacterial eradication, i.e., the bacterial eradication rate in the treatment was 100%. (3) There were 2 cases in which side-effects were observed among the analyzed 152 cases (1.3%). The side effects found were 1 case each of diarrhea and eruption. Abnormal laboratory values were found in 23 cases (15.9%), i.e., eosinophilia (9 cases), platelet-increase (4), elevation of GOT (4), elevation of GOT and GPT (3) and others (3). From the above pharmacokinetics and clinical results, the combination therapy of AZT and ABPC is considered to be one of the useful empiric antibiotic-therapies when pathogenic organisms are unknown in the infections of neonates and premature infants.

Ampicillin↗
PubMed1990

[Clinical and pharmacokinetic evaluation of cefdinir in children].

Thirty children were treated with cefdinir (CFDN) for the evaluation of its clinical efficacy and side effects. Their ages ranged from 1 to 9 years. The dosage of CFDN ranged from 8.1 to 15.9 mg/kg/day with the treatment continued for 2 to 10 days. Twenty-eight of the 30 patients were evaluated for clinical efficacy; 10 patients with tonsillitis, 3 with scarlet fever, 4 with lower respiratory infections, 2 with otitis media, 2 with cervical lymphadenitis, 3 with urinary tract infections and 4 with skin and soft tissue infections. The remaining 2 patients who had viral diseases were included in the evaluation for side effects. Clinical responses were excellent in 14 patients, good in 12, fair in 1 and poor in 1 with an efficacy rate of 92.9%. Diarrhea was noted in one of the 30 patients. A pharmacokinetic study on CFDN was performed in 8 fasting patients whose ages ranged from 3 to 7 years. Serum concentrations of CFDN peaked at 0.59 to 1.76 micrograms/ml (mean 1.13 microgram/ml) at 2 hours after dosing of 3 mg/kg in 4 patients, and 0.89 to 2.49 micrograms/ml (mean 1.49 micrograms/ml) 2 or 3 hours after dosing of 6 mg/kg in the other 4 patients. The 8-hour urinary excretion rates were 16.0% to 21.3% (mean 17.4%) in 4 patients given a dose of 3 mg/kg and 10.9 to 21.1% (mean 15.5%) in 4 patients given a dose of 6 mg/kg.

Administration, Oral↗
PubMed1990

[Clinical and pharmacokinetic evaluation of aztreonam in neonates].

Nine neonates were treated with aztreonam (AZT) and its clinical efficacy and side effects were evaluated. Six of the patients were treated with a combination of AZT and ampicillin. Ages of the patients ranged from 0 to 24 days, and their body weights ranged from 2,290 to 4,260 g. Doses of AZT ranged 18.8 to 23.7 mg/kg every 8 to 12 hours for 3 to 7 days. Three patients with infections including urinary tract infection, cervical abscess, and suspicion of sepsis, appeared to respond to the treatment of AZT alone. Among them, clinical results were excellent in 1, good in 2 patients. Those patients subjected to the combination therapy showed excellent response in 1 and good in 5. The drug was well tolerated, but 1 had diarrhea. The pharmacokinetics of AZT was studied in 9 patients. Their ages ranged from 0 to 30 days, and body weights ranged from 2,000 to 4,000 g. Serum concentrations of AZT were 27.2 to 48.3 micrograms/ml at 1 hour after single 20 mg/kg intravenous bolus injection, and the levels were 3.4 to 15.5 micrograms/ml at 6 hours in 5 infants heavier than 2,500 g. Elimination half-lives of AZT ranged from 1.57 to 3.72 hours (mean 2.72 hours). Serum concentrations of AZT were 21.6 to 41.8 micrograms/ml at 1 hour after single 20 mg/kg intravenous bolus injection, and the levels were 10.2 to 17.0 micrograms/ml at 6 hours in 3 infants lighter than 2,500 g. The elimination half-lives of AZT were 3.63 to 4.86 hours (mean 4.31 hours).(ABSTRACT TRUNCATED AT 250 WORDS)

Ampicillin↗
PubMed1989

Acinetobacter calcoaceticus biovar anitratus septicaemia in a neonatal intensive care unit: epidemiology and control.

Nineteen neonates with septicaemia caused by Acinetobacter calcoaceticus biovar anitratus were treated in a neonatal intensive care unit between October, 1983 and March, 1986. The ages of the patients at the onset of septicaemia ranged from 4 to 22 days (mean 9.7 days). Their birth weights ranged from 1000 g to 3350 g (mean 1790 g) and were less than 2000 g in 14 patients. Antibiotics had been administered to 17 of the 19 neonates before the onset of septicaemia, and all mature infants had received prior antibiotic therapy, intubation or had suffered from a convulsion. Acinetobacter anitratus strains were isolated from pharyngeal swabs and/or faeces from 35 (79.5%) out of 44 infants of less than 2000 g. These strains were also isolated from the hands of staff members, and from equipment such as sinks and baths in the unit. It was likely that nosocomial infection via the hands of the staff occurred. Encouraging frequent hand-washing, strict antibiotic use, and cohorting of colonized infants resulted in a reduction of colonization and no further cases of septicaemia were reported.

Acinetobacter↗
PubMed1989

Detection of pulmonary telangiectasia using dynamic pulmonary perfusion imaging in patients with liver cirrhosis.

Two cases of liver cirrhosis associated with marked hypoxemia are presented. Chest radiographs and cardiopulmonary function showed no abnormalities, except for the low diffusion capacity of carbon monoxide and slight elevation of the shunt ratio (20 and 6.2%, respectively), as estimated under conditions of 100% oxygen inhalation. Pulmonary perfusion imaging with Tc-99m macroaggregated albumin (MAA) revealed a significant radioisotope uptake in the lungs, brain, spleen, and both kidneys. Shunt ratios, estimated by the quantitative radionuclide method, were 60 and 68%, respectively. Dynamic pulmonary perfusion imaging revealed a gradual reduction in uptake in all areas of both lungs. The discrepancy of the shunt ratio between the two methods results from an abnormal dilatation of alveolar capillaries. The gradual reduction of radioactivity in areas of the lungs is caused by the passage of MAA particles through widened pulmonary capillaries.

Female↗
PubMed1989

Reversibility of pulmonary telangiectasia in liver cirrhosis evidenced by serial dynamic pulmonary perfusion imaging.

Pulmonary perfusion imaging with Tc-99m MAA revealed significant uptake in the lungs, brain, spleen, and both kidneys of a 48-year-old woman with liver cirrhosis and pulmonary telangiectasia associated with marked hypoxemia and cyanosis. Dynamic pulmonary perfusion imaging revealed a gradual reduction after peak uptake in both lungs. Several weeks after albumin replacement, the hypoxia and dyspnea disappeared with no change in hepatocellular function. At that time, dynamic pulmonary perfusion imaging revealed a plateau-like time-activity curve of uptake in the lungs, as compared with the findings obtained during the state of severe hypoxemia. These observations suggest that pulmonary telangiectasia in a patient with liver cirrhosis may be due to functional vasodilatation. Serial dynamic pulmonary perfusion imaging indicates the passage of the MAA particles through the widened lumen of the pulmonary alveolar capillaries.

Female↗
PubMed1989

[Selective decontamination of intestinal flora with oral aztreonam in compromised children].

Effects of oral aztreonam on fecal flora were studied in 6 compromised children. Their ages ranged from 4 to 14 years. Daily doses of aztreonam were 10 to 30 mg/kg. The stool specimens were obtained before the treatment, on day 5 to 7 of aztreonam use and 2 to 5 days after the cessation of treatment. The counts of enterobacteria decreased from 10(7.7) to 10(4.4) per gram of wet feces (p less than 0.01), and bifidobacteria also decreased from 10(10.2) to 10(8.4) per gram of wet feces (p less than 0.01) during aztreonam administration. Those of streptococci increased from 10(2.9) to 10(9.4) per gram of wet feces (p less than 0.001). The other anaerobic organisms showed no marked change. Based upon the above results, we conclude that oral administration of aztreonam may be useful for selective decontamination of intestinal flora in compromised hosts.

Administration, Oral↗
PubMed1989

Fetal blood values by percutaneous umbilical blood sampling.

Cordocentesis was performed, and fetal blood was sampled in 81 of 93 attempted procedures. In 45 fetuses, who proved to be normal later by normal pregnancy outcome, hematological analyses and blood chemistries were performed. The results showed an increase in total white blood cell count, red blood cell, hemoglobin, hematocrit and platelet count, while the mean corpuscular volume and mean corpuscular hemoglobin decreased during gestation. Total protein and albumin concentrations increased during pregnancy. These results provide information for the diagnosis of fetal hematological disorders, and assist in making decisions for possible fetal therapy in utero.

Female↗
PubMed1989

[Usefulness of bone imaging in diagnosis of sternocostoclavicular hyperostosis].

Sternocostoclavicular hyperostosis (SCCH) is a rare disease that is characterized by hyperostosis and soft tissue ossification between the clavicles and the anterior part of the upper ribs. There have been few published reports of 99mTc-MDP bone imaging findings in this disease. Thirty-three patients who were suspected to have SCCH were studied with 99mTc-MDP bone imaging. Bone images were abnormal in 31 (94%) of 33 patients. Chest radiographs were available in 30 patients, but negative in 14 (46%) of them. Bone imaging revealed also radionuclide accumulations in other bones such as the vertebrae, femur or sacroiliac joints in ten (14 sites) of 33 cases. Bone scintigraphy was useful in the diagnosis of sternoclavicular hyperostosis.

Adult↗
PubMed1989

[Clinical and pharmacokinetic evaluation of cefsulodin in neonates and young infants].

Four neonates and young infants were treated with cefsulodin (CFS) at doses ranging from 20-25 mg/kg every 6 hours for 6.25 to 17 days, and clinical efficacy and side effects were evaluated. Among the 4 infants with bacterial infections including meningitis, bronchitis and pneumonia, the results were good in 2 patients with meningitis, but unknown in 2 patients because of additional use of gentamicin. One of the 4 patients had eosinophilia. Minimal inhibitory concentrations of CFS against 4 isolates of Pseudomonas aeruginosa were 1.56 against one and 12.5 micrograms/ml against other 3 strains with an inoculum size of 10(3) CFU. Serum concentrations of CFS were measured in one- and four-month-old infants upon 25.3 and 20.9 mg/kg bolus intravenous injection of the antibiotic, respectively. The values were 36.4 and 33.4 at 30 minutes, and 5.1 and 3.2 micrograms/ml at 6 hours after injection, respectively. Serum half-lives were 1.89 and 1.69 hours, respectively. Total body clearances and volume distributions were 3.16 and 3.76 ml/min/kg, and 519.0 and 551.2 ml/kg, respectively.

Bronchitis↗
PubMed1989

Malignant mixed mesodermal tumour of the peritoneum with a complete response to cyclophosphamide.

We treated a 66-year-old Japanese woman with malignant mixed mesodermal tumour of the heterologous type arising from the paracolic peritoneum. The tumour contained heterologous elements in the form of cartilage in addition to carcinosarcomatous areas. This is the third case of malignant mixed mesodermal tumours originating from the peritoneum to be documented in the literature. A complete resection of the tumour was carried out but multiple lymph nodes metastases in the left neck occurred 5 months later. Cyclophosphamide in doses of 150 mg daily by mouth was initiated, with the result of a complete regression of the malignant lesions. She died of myocardial infarction 21 months after surgery.

Aged↗
PubMed1989

[Clinical and pharmacokinetic evaluation of cefmenoxime in neonates and young infants].

Twenty-three newborn and young infants, including 13 low-birth-weight infants, were treated with cefmenoxime (CMX) and the clinical efficacy and side effects were evaluated. The ages of the patients ranged from 1 to 102 days, and their weights ranged from 0.83 to 4.19 kg. Doses given were 18-42 mg/kg every 6 to 12 hours for 2 to 16 days. Among 12 infants with bacterial meningitis and sepsis, the results were excellent in 2, good in 7 and fair in 3 patients. The drug was well tolerated and no adverse effects were observed in the 23 patients. Pharmacokinetic studies of CMX were done in 5 infants whose mean body weight was 3.03 kg (range 2.4 to 4.2 kg). Serum concentrations at 15 minutes after 10 mg/kg intravenous bolus injections were 35.6 and 55.7 micrograms/ml in two 12- and 18-day-old patients. In 3 patients with ages of 7, 7 and 24 days, serum concentrations were 54.6, 102 and 100 micrograms/ml, respectively, at 15 minutes after 20 mg/kg doses. Elimination half-lives of the drug were 1.3 to 1.5 (mean 1.4) hours in these patients. Excretion rates into urine in the first 8 hours were 30.3, 74.2, 77.6 and 85.6% in four patients given 10 or 20 mg/kg doses. The cerebrospinal fluid level at 3 hours after the dose was 0.4 micrograms/ml on 15th day of treatment in 1 patient with bacterial meningitis given 20 mg/kg every 6 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Cefmenoxime↗
PubMed1989

[Anti-glomerular basement membrane antibody-mediated glomerulonephritis remarkably improved by pulse therapy with methylprednisolone, plasmapheresis and continuous heparin infusion].

The patient, a 28 year-old-man, was admitted to a hospital because of general fatigue and fever. He was pointed out renal dysfunction and was transferred to Nagasaki University Hospital. The laboratory data on admission showed moderate azotemia (BUN 43 mg/dl, Cr 5.4 mg/dl). A percutaneous renal biopsy on admission revealed a diffuse crescentic glomerulonephritis. A direct immunofluorescence of renal biopsy showed a linear pattern for IgG along the glomerular basement membrane. Radioimmunoassay of his serum for circulating anti-GBM antibody was strongly positive. Aggressive treatment with pulse therapy (methylprednisolone), plasmapheresis, and continuous heparin infusion was performed. He had markedly recovered from renal failure and escaped hemodialysis. The patient is making satisfactory process after 3 years.

Adult↗
PubMed1989

[Pharmacokinetic and clinical evaluation of imipenem/cilastatin sodium in neonates and premature infants. A study of imipenem/cilastatin sodium by a perinatal co-research group].

Pharmacokinetics and clinical studies of imipenem/cilastatin sodium (IPM/CS), a combined preparation of a new carbapenem antibiotic and a dehydropeptidase-I inhibitor, respectively, were carried out in neonates and premature infants in a joint study by a co-research group. 1. Peak blood levels of IPM/CS when administered at 10 mg/10 mg/kg or 20 mg/20 mg/kg by 30- or 60-minute intravenous drip infusion were achieved at the end of infusion. A dose response was clearly observed between the doses and the peak levels achieved. 2. The areas under the blood concentration time curve (AUC) of CS were greater than those of IPM in most patients. Blood half-lives of IPM and CS tended to be longer in younger neonates and premature infants than in older subjects. The blood half-life of CS tended to be longer than that of IPM. 3. Cumulative urinary recovery rates of CS were greater than those of IPM, cumulative urinary recovery rates tended to be greater in older neonates and premature infants than younger subjects. 4. One hundred and thirteen patients were treated for bacterial infections with IPM/CS and 32 patients were treated prophylactically. Daily doses of IPM/CS ranged from 9 mg/9 mg/kg to 150 mg/150 mg/kg. 5. Clinical efficacies of IPM/CS were evaluated in a total of 56 patients with identified etiologic pathogens. The efficacy rate was 98.2% with 33 patients rated as excellent, 22 patients as good and 1 patient as fairly good. (Diagnoses were sepsis in 10 patients and meningitis in 2 patients, etc.) Fifty-seven patients with no identified etiologic pathogens were rated as excellent for 22 patients, good for 34 patients and fairly good for 1. The efficacy rate in these patients was 98.2%. Thirty-two patients were treated prophylactically and the results obtained were satisfactory. 6. Bacteriologically, the eradication rate was 94.5% in 56 patients; i.e., 52 were eradicated, 2 were decreased, 1 persisted and 1 was unknown. 7. Adverse effects were observed in 7 (4.4%) of 160 patients, i.e., 2 patients had diarrhea and 2 patients had rash, etc. Abnormal laboratory data considered related to the therapy occurred in 28 (17.6%) of 159 patients, with 10 patients with eosinophilia (6.3%) and elevation of GOT and/or GPT, etc. All these were non serious, and all values returned to normal after discontinuance of therapy. An abnormal prothrombin (PIVKA II) was observed in 1 of 10 patients tested.(ABSTRACT TRUNCATED AT 400 WORDS)

Age Factors↗
PubMed1989

[Overall clinical evaluation of cefpodoxime proxetil against infections in pediatric fields].

Dry syrup and tablet of newly developed cefpodoxime proxetil (CS-807, CPDX-PR) was investigated in the departments of pediatrics of 17 institutes and their related hospitals. 1. Pharmacokinetics of CPDX-PR in pediatrics were investigated. Peak blood levels of CPDX at dose levels of 3 mg/kg and 6 mg/kg were 2.24 +/- 0.21 and 4.68 +/- 0.54 micrograms/ml, respectively, in fasting and 1.65 +/- 0.07 and 3.71 +/- 0.41 micrograms/ml, respectively, after meal. Urinary recovery rates in 6 hours were 31.2 +/- 2.2% of dose in average. 2. Clinical efficacies of CPDX-PR on various infectious diseases were studied in 748 cases. Clinical efficacy rate in 499 cases with causative bacteria isolated was 94.6%: efficacy rates for individual infections were 96.8% (120/124) for tonsillitis, 96.0% (96/100) for urinary tract infection, 93.5% (58/62) for pneumonia, 92.4% (61/66) for impetigo, 100% (32/32) for scarler fever and 93.2% for pharyngitis or laryngitis. Bacteriological eradication rate for Gram-positive organisms was 91.0% (244/268); and for Gram-negative organisms, 89.7% (210/234). The clinical efficacy rate for cases which were non-responsive to previous antibiotic therapy was 88.1% (74/84). 3. Side effects and clinical laboratory findings were investigated in 779 cases. Two each of vomiting, loose stool and rash, 10 of diarrhea and 1 of diarrhea associated with candidiasis were reported, but no serious side effects were noted. There was no serious laboratory test abnormality except slight elevations of eosinophile, platelet, transaminase or prolongation of prothrombin time, totalling 34 occurrences.

Administration, Oral↗