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K Numata

Publications and source records attributed to K Numata.

At least 37 records · Page 2Linked to original sources
PubMed1990

Calcium-dependent anticandidal action of pradimicin A.

Pradimicin A shows candicidal activity at 10 micrograms/ml in vitro. The action of pradimicin A on Candida albicans cells involves a set of specific cell surface interactions in a Ca2(+)-dependent manner. These include binding to the mannan components on the cell surface and subsequent interactions at the level of the plasma membrane, causing K+ leakage and cell death. The protoplasts prepared from C. albicans undergo lysis rapidly when treated with pradimicin A. These results suggest that pradimicin A acts primarily on the candidal plasma membrane, leading to a perturbation of membrane function.

Anthracyclines↗
PubMed1990

Biochemical and histological findings on the effect of fibronectin in rabbits with experimental corneal disorders.

The effects of purified plasma fibronectin (FN) in corneal disorders were investigated. Histological findings, the levels of ascorbic acid (AA) and glutathione (GSH) in tear fluids were observed sequentially in rabbits with experimental corneal damage and the degree of corneal lesions was observed. The results indicated that healing of the tissue damage was more promoted in the FN group than in the controls and it was suggested that FN promoted the healing of corneal disorders.

Animals↗
PubMed1990

[A pharmacodynamic analysis of the onset of neuromuscular blockade by nondepolarizing muscle relaxants--the pharmacodynamics of a large dose of vecuronium].

From Sheiner's equation on pharmacokinetics and pharmacodynamics, we derived a new equation which described the pharmacodynamics of nondepolarizing muscle relaxants during the onset phase. This equation showed that log (l0/l-1) had a linear relation to log (t) where "t" is the time after the administration of nondepolarizing muscle relaxant and "l" and "l0" are the twitch height at t = t and t = 0 respectively. It also implies that the administration dose (D) is inversely proportional to the onset time (OT), i.e., D.OT = const. We proved that these two relations held well for the actual 7 cases of vecuronium use in man. In conclusion, when vecuronium dose level was within 0.15-0.30 mg.kg-1 i.v., the dose was inversely proportional to the onset time which was defined as the time interval from the end of the administration of vecuronium until the single twitch was depressed under 5% of control value, i.e., Dose (mg.kg-1) x onset-time (sec) not equal to 24. During anesthesia with enflurane as well as during neuroleptanesthesia, a dose of vecuronium 0.3 mg.kg-1 (n = 7) was found to produce a duration of neuromuscular blocking action equal to the mean duration produced by pancuronium 0.1 mg.kg-1.

Adult↗
PubMed1990

[Comparative pharmacokinetics of pipecuronium bromide, pancuronium bromide and vecuronium bromide in anesthetized man].

The pharmacokinetics of pipecuronium bromide was studied in 9 male patients (ASA class 1-2, 20-65 years of age). Following a single intravenous dose of pipecuronium 0.08 mg.kg-1, plasma levels were measured by capillary gas chromatography. Plasma concentration-time curves were evaluated by fitting the data to a bi-exponential equation. The pharmacokinetic parameters of pipecuronium were compared with those of pancuronium (0.08 mg.kg-1) and vecuronium (0.08 mg.kg-1) previously obtained under the same anesthesia (66% N2O, 33% O2 and 1% halothane). With pipecuronium, following pharmacokinetic parameters were obtained; distribution half-life; T1/2 alpha = 3.9 +/- 0.7 min (mean +/- SEM), elimination half-life; T1/2 beta = 102 +/- 12 min, volume of the central compartment; V1 = 95 +/- 13 ml.kg-1, volume of distribution at steady state; Vdss = 264 +/- 41 ml.kg-1, clearance; Cl = 1.8 +/- 0.2 ml.min-1.kg-1. Microconstants of two-compartment open models (k12, k21, k10) were also calculated. Using Mann-Whitney's U-test, these parameters of pipecuronium were compared with those of pancuronium (n = 3) and vecuronium (n = 4). V1 and Vdss of pipecuronium were significantly larger than those of pancuronium (V1; 38 +/- 12 ml.kg-1 and Vdss; 120 +/- 4 ml.kg-1) (both P less than 0.10). Reflecting the larger central volume of pipecuronium, pipecuronium tended to have a larger clearance than that of pancuroniumu (Cl; 1.1 +/- 0.2 ml.min-1.kg-1).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Evaluation of the action of pipecuronium bromide in patients under halothane anesthesia--a comparison with pancuronium bromide regarding their neuromuscular blocking and cardiovascular effects].

Neuromuscular blocking and circulatory actions of pipecuronium bromide (PPB) were evaluated in patients under halothane-nitrous oxide-oxygen anesthesia in comparison with those of pancuronium bromide (PCB) in a multi-center cooperative study. Twitch tension of the adductor pollicis muscle was elicited by supramaximal stimulation of the ulnar nerve every 10 seconds. The study was performed according to the following 4 steps and the results were obtained. 1) Cumulative administration of 0.01 mg.kg-1 of PPB or PCB resulted in the potency ratio of 1.3:1.0 and the dose response curves of the two agents paralleled with each other. 2) With PPB 0.05 mg.kg-1 or 0.1 mg.kg-1, almost 100% block of the twitch was obtained. Both duration of action and the recovery time were shorter with 0.05 mg.kg-1 group. 3) After the first dose of 0.04 mg.kg-1 when the twitch recovered to 25% of the initial height 0.02 mg.kg-1 was given and this was repeated. Intervals between the doses showed large individual differences and no significant change was observed with repeated doses. 4) Safety of the drug. No significant change in heart rate or blood pressure was observed with PPB but with PCB a significant increase in heart rate was observed. The study revealed that PPB is slightly more potent than PCB and the duration of action is longer, but it has no untoward cardiovascular action in man under halothane anesthesia.

Adult↗
PubMed1990

[A case of delayed radiation lumbo-sacral plexopathy].

We report a 47-year-old woman who developed a slowly progressive lumbosacral plexopathy with mixed sensorimotor losses in the lower extremities. The symptoms were apparent 8 years after x-ray irradiation for an ovarian carcinoma. Neurological examination showed mild weakness and absent deep tendon reflexes of bilateral lower extremities, and hypesthesia to all modalities in anterior aspects of bilateral lower thighs, in dorsum pedis and soles. Extensive investigations regarding the possibility of tumor recurrence were negative. Computed tomography of pelvis showed abnormal soft tissue densities around the lumbosacral plexus. Intravenous pyelography showed bilateral hydronephrosis and narrowed ureters at the first sacral vertebra level. These findings are consistent with radiation-induced fibrosis rather than tumor infiltration. The results suggest the entrapment lumbosacral plexopathy due to surrounding fibrosis after irradiation. We speculated the sensorimotor losses caused by entrapment of the lumbosacral plexus.

Female↗
PubMed1990

[A benzodiazepine antagonist flumazenil in clinical use--a dose finding study].

The effective dose, usefulness and side effects of flumazenil, a specific benzodiazepine antagonist, have been investigated in 72 sleeping patients after the end of the surgical operation who had received flunitrazepam 0.03 mg.kg-1, a long acting benzodiazepine. The patients received intravenous injections of flumazenil 0.1 mg, 0.2 mg, 0.4 mg and 0.8 mg per person as initial doses. Four minutes after the injection of flumazenil, the percentages of the patients who were awake, were 47.4% in 0.1 mg group, 82.4% in 0.2 mg group, 82.4% in 0.4 mg group and 88.2% in 0.8 mg group respectively. There were several side effects observed in all the groups except 0.2 mg group. However, they presented no clinical problems. Therefore, flumazenil 0.2 mg as the initial dose, is considered appropriate.

Adolescent↗
PubMed1990

[Effect of induced hypotension on arterial blood ketone body ratio (AKBR)].

Arterial blood ketone body ratio (AKBR; acetoacetate/beta-hydroxybutyrate) is known as a parameter to indicate the function of the liver cells. We evaluated the effects of induced hypotension with prostaglandin E1 (PGE1) or trimetaphan (TMP) on AKBR in patients without liver disease undergoing mastectomy. Almost no change was observed in AKBR before, during and after hypotension with PGE1, but slight diminution was observed during hypotension with TMP. No hepatic dysfunction, however, developed in these patients postoperatively. These findings suggest that usual hypotension with TMP may provoke no postoperative hepatic dysfunction in patients without liver disease. For the patient who required either hypotension of long duration or hypotension with other factors affecting function of liver (surgical procedures, drugs and others), we prefer PGE1 to TMP as a hypotensive drug. We should also adopt PGE1 when cardiovascular control with hypotensive drug is necessary in patients with liver disease.

Alprostadil↗
PubMed1989

Phasic capillary pressure determined by arterial occlusion in intact dog lung lobes.

In six open-chest dogs, electrocardiogram- (ECG) controlled pulmonary arterial occlusion was performed during the control period and during the infusions of serotonin and histamine. A temporal series of instantaneous pulmonary capillary pressure and the longitudinal distributions of vascular resistance and compliance were evaluated in the intact left lower lung lobe. In the control period, we found a significant phasic variation of pulmonary capillary pressure (Pc) with the cardiac cycle. The ratio of arterial to venous resistances (Ra/Rv) was 6:4, and the ratio of arterial to capillary compliances (Ca/Cc) was 1:11. During the infusions of serotonin and histamine, Pc showed similar phasic variations, despite significant hemodynamic changes induced by these agents. Serotonin predominantly increased Ra, whereas histamine predominantly increased Rv. The ratio of Rv to the total resistance decreased significantly from 0.42 to 0.32 during the infusion of serotonin and increased significantly to 0.62 during the infusion of histamine. The data suggest that phasic Pc determined by ECG-controlled arterial occlusion reflects the pulsatility in the pulmonary microvascular bed under control conditions and after alterations of the pulmonary vascular resistance by serotonin and histamine.

Animals↗
PubMed1989

Cispentacin, a new antifungal antibiotic. II. In vitro and in vivo antifungal activities.

Cispentacin [-)-(1R,2S)-2-aminocyclopentane-1-carboxylic acid) is a new antifungal antibiotic possessing potent anti-Candida activity. The 50% inhibitory concentration (IC50) and IC100 values of cispentacin against clinical isolates of Candida albicans were in the ranges 6.3 approximately 12.5 and 6.3 approximately 50 micrograms/ml, respectively, by turbidimetric measurement in yeast nitrogen base glucose medium. No significant activity was seen against any yeasts and molds when tested by the agar dilution method using three different agar media: KNOPP's agar, yeast extract-glucose-peptone agar and Sabouraud dextrose agar. This antibiotic demonstrated good therapeutic efficacy against a systemic Candida infection in mice by both parenteral and po administrations. The 50% protection dose (PD50) values after single iv and po administrations were 10 and 30 mg/kg, respectively. It was also effective in a systemic infection with Cryptococcus neoformans and in both lung and vaginal infections with C. albicans in mice. Cispentacin did not induce acute lethal toxicity at 1,000 mg/kg by iv injection and 1,500 mg/kg by ip and po administrations in mice.

Amphotericin B↗
PubMed1989

[Periodic sublingual buprenorphine for pain relief after upper abdominal surgery].

Analgesic effects were evaluated in patients who received sublingual administration of buprenorphine (0.2mg ampule for injection) as programmed every 8 hours for 3 days following upper abdominal surgery. Patients who received periodic sublingual buprenorphine obtained satisfactory postoperative analgesia and also required less analgesics than those who never received periodic administration of analgesics. Approximately one half of patients who received periodic sublingual buprenorphine required no additional analgesics. Arterial blood-gas analysis showed a significant increase in carbon dioxide tension after sublingual buprenorphine. One patient revealed marked respiratory acidosis after sublingual buprenorphine. These results suggest that periodic sublingual buprenorphine makes up for slow onset in sublingual administration and that it is also effective, convenient, and safe for pain relief after upper abdominal surgery. We, however, should pay attention to the respiratory depression caused by sublingual buprenorphine.

Abdomen↗
PubMed1989

[Comparison of O2 saturation measurements by oximetry and by gas analysis].

For checking the reliability of pulse oximetry in the operating rooms, we compared values of arterial O2 saturation measured by a blood gas analyzer (SAT) with values monitored by pulse oximetry (SaO2). SaO2's were found to be significantly different from SAT's. The regression equation was SAT = 0.31 X SaO2 + 68.4 and the correlation coefficient was 0.66. P value of paired comparison was 0.0001 indicating that the two sets of values were not equal to each other. When one observer performed a similar study using a high-fidelity pulse oximeter, SaO2's were not different from SAT's. The regression equation in this case was SAT = 0.85 X SaO2 + 15.0 and the correlation coefficient was 0.95. P value of paired comparison was 0.3244. The reliability of pulse oximetry differs from one anesthesiologist to another and depends upon the accuracy of each pulse oximeter. In clinical experiment, using the data by pulse oximetry in operating room is misleading.

Blood Gas Analysis↗
PubMed1988

Glidobactins A, B and C, new antitumor antibiotics. II. Structure elucidation.

The structures of new antitumor antibiotics, glidobactins A (Ia), B (Ib) and C (Ic) were elucidated by a combination of chemical and enzymatic degradations and spectral analyses. They have in common a cyclized tripeptide nucleus composed of L-threonine, 4(S)-amino-2(E)-pentenoic acid and erythro-4-hydroxy-L-lysine, and differ from each other in the unsaturated fatty acid moiety attached to the peptide.

Amino Acids↗
PubMed1988

Enzymatic formation of glidobactamine: a peptide nucleus of glidobactins A, B and C, new lipopeptide antitumor antibiotics.

Glidobactin deacylating activity was found in a bacterial strain of Pseudomonas sp. Glidobactamine, a key intermediate for acyl analogues of glidobactin, was isolated from the enzymatic degradation products of glidobactins after treatment using a column of fibrous active gel on which the cells of the Pseudomonas strain were immobilized. The chemical structure of glidobactamine was confirmed as the intact peptide moiety of glidobactins by chemical reformation of glidobactin A from glidobactamine and 2,4-dodecadienoic acid which is the constitutive fatty acid of glidobactin A.

Antibiotics, Antineoplastic↗
PubMed1988

Enhanced production of the minor components of glidobactins in Polyangium brachysporum.

Polyangium brachysporum sp. nov. strain ATCC 53080 produces a novel type of antifungal and antitumor antibiotic complex, glidobactins A, B and C. Enhanced production of minor components, glidobactins B and C, was achieved by medium modification. The addition of soybean oil or corn oil, which are rich in unsaturated C18 fatty acids, to the fermentation medium led to an increased production of components B and C. Productivity of component C was selectively enhanced by the addition of oleic acid-rich oils, olive oil and Tween 80 (polyoxyethylene sorbitan mono-oleate). Furthermore, precursing palmitoleate, linoleate and oleate permitted the direct biosynthesis of components A, B and C, respectively. The fermentation with 3% addition of an appropriate oil at initial time provided an optimal production of component B or C.

Antibiotics, Antineoplastic↗
PubMed1988

Chemical modification of the antitumor antibiotic glidobactin.

A variety of glidobactin analogs modified at the fatty acid, L-threonine and nucleus moieties of the molecule were synthesized and their structure-activity relationships examined. The antitumor and antifungal activity was greatly influenced by modification of the fatty acid glidobactin, with the dodecanoyl and tetradecanoyl analogs exhibiting better antitumor activity than the parent antibiotics. Replacement of the L-threonine with other amino acids greatly reduced the activity and reduction of the double bond of the nucleus completely eliminated the biological activity of glidobactin.

Antibiotics, Antineoplastic↗