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Biomedical subjects

Y Hatano

Publications and source records attributed to Y Hatano.

At least 145 records · Page 8Linked to original sources
PubMed1990

Enzyme-linked immunosorbent assay for detection of IgG antibody to human herpesvirus 6.

A lysate of human herpesvirus 6 (HHV-6)-infected cord blood mononuclear cells was used as antigen for enzyme-linked immunosorbent assay for the detection of IgG antibody to HHV-6. Antibody responses after exanthem subitum were well correlated with clinical recovery from the disease and the level of antibody activities was well correlated with indirect immunofluorescence assay and the neutralization test. Seroconversion to other human herpesvirus, including cytomegalovirus, was not observed in infants with exanthem subitum. All of the infants had by the age of 1 month antibodies to HHV-6, which decreased with age to the lowest level at the age of 3 to 6 months and then increased and reached the maximum level by 1 to 2 years of age. After 3 years of age, the prevalence was almost stable.

Adolescent↗
PubMed1990

Contribution of prostacyclin to D-tubocurarine-induced hypotension in humans.

In order to evaluate the role of prostacyclin in d-tubocurarine-induced hypotension in human, the authors examined the relationship of changes of arterial blood pressure and plasma 6-keto-PGF1 alpha level following iv administration of d-tubocurarine (dTc), with or without prior administration of aspirin and H1 antagonist. The bolus injection of dTc 0.6 mg/kg caused a significant decrease in mean arterial pressure (MAP) that was associated with a significant increase in plasma 6-keto-PGF1 alpha (P less than 0.05 in both). The maximum MAP decrease and plasma 6-keto-PGF1 alpha increase were noted at 2 min after dTc administration. Pretreatment with aspirin DL-lysine (25 mg/kg) or diphenhydramine (1 mg/kg) significantly attenuated the responses of MAP (P less than 0.05 in both) and plasma 6-keto-PGF1 alpha level (P less than 0.01 for aspirin group, P less than 0.05 for diphenhydramine group). There was a significant correlation between the changes in plasma 6-keto-PGF1 alpha and those in MAP (Kendall tau (tau) = -0.504, P less than 0.01). These findings suggest that a bolus injection of dTc induces a release of prostacyclin through H1 receptor, which is responsible for the dTc-induced transient decrease of blood pressure in humans.

6-Ketoprostaglandin F1 alpha↗
PubMed1990

Comparison of the direct effects of halothane and isoflurane on large and small coronary arteries isolated from dogs.

Relaxant responses to halothane and isoflurane were compared in helical strips of dog epicardial coronary arteries of different sizes: proximal large coronary arteries with outside diameters (OD) larger than 2.5 mm and distal small arteries with 0.7-0.9 mm OD. Responses to pharmacologic vasodilators, including nitroglycerin (NTG) and adenosine, were also studied for comparison. The relaxation induced by halothane in concentrations of 0.8-2.3% and by NTG (10(-9)-10(-5) M) was greater in proximal large coronary arteries than in distal small ones contracted with 20 mM KCl. In contrast, the relaxation by isoflurane (1.2-3.5%) and by adenosine (10(-8)-10(-4) M) was greater in small coronary arteries than in large ones. These results suggest that isoflurane is, like adenosine, preferentially a small artery dilator.

Adenosine↗
PubMed1990

Effects of halothane on the efflux of [3H]D-aspartate from rat brain slices.

The in vitro effects of halothane on the potassium-stimulation-induced efflux of [3H]D-aspartate in rat cerebral cortex slices were studied. The slices were initially incubated with Krebs-Ringer's solution containing [3H]D-aspartate, a putative excitatory transmitter. The slices were then stimulated with high concentrations of K+ in the presence and absence of halothane, and the efflux was measured using a scintillation counter. Halothane, 1% and 2%, had little effect on the potassium-stimulation-induced efflux, but that of 4 and 8% increased the efflux significantly. The spontaneous efflux was unaffected by all concentrations of halothane studied. The control study of pentobarbital, in the concentration of 0.05 to 1.00 mmol/l, reduced the efflux in a dose-related manner. These findings indicate that the release of an excitatory transmitter, aspartate, may not be involved in the mechanism of halothane anaesthesia.

Animals↗
PubMed1990

Responses to barbiturates of isolated dog cerebral and mesenteric arteries contracted with KCl and prostaglandin F2 alpha.

In helical strips of dog cerebral and mesenteric arteries previously contracted with KCl or prostaglandin F2 alpha (PGF2 alpha), the addition of pentobarbital (10(-5) to 10(-3) mol.l-1) caused dose-related relaxation, whereas thiamylal and thiopental in a low concentration (10(-5) to 10(-4) mol.l-1) caused further contraction and in a high concentration (10(-3) mol.l-1) profound relaxation. Thiobarbiturate-induced contractions were greater in mesenteric than in cerebral arteries previously contracted with PGF2 alpha. In cerebral and mesenteric arteries exposed to Ca(++)-free media for 60 min and treated with KCl or PGF2 alpha, reintroduction of Ca++ produced a transient contraction, a transient relaxation and a persistent contraction. The Ca(++)-induced persistent contraction was attenuated by pretreatment with pentobarbital (10(-4) to 10(-3) mol.l-1) and thiamylal (10(-3) mol.l-1); the attenuation was greater in arteries treated with KCl than with PGF2 alpha. The Ca(++)-induced contractions of mesenteric artery treated with PGF2 alpha were potentiated by 10(-4) mol.l-1 thiamylal. It is concluded that pentobarbital possesses only a vasodilator effect, whereas thiamylal and thiopental have both constrictor and dilator effects on vascular smooth muscle. The vasodilator effect of barbiturates is associated in part with inhibition of transmembrane influx of Ca++; the inhibition is more predominant on the influx evoked by KCl-induced depolarization than by a stimulation of PGF2 alpha receptors. Thiamylal in low concentrations appears to enhance Ca++ influx through a receptor-operated Ca++ channel for PGF2 alpha.

Animals↗
PubMed1990

Effects of thiobarbiturates on smooth muscle reactivity in isolated aortas from spontaneously hypertensive rats.

The direct effects of thiobarbiturates on helical strips of aortas from spontaneously hypertensive (SH) rats were compared with those from Wistar-Kyoto (WKY) rats. At 5-6 wk of age, the arterial pressure of SH and WKY rats did not differ, and the effects of thiobarbiturates on aortic strips from SH and WKY rats were similar. By contrast, at the age of 10-12 or 20-21 wk arterial pressure was higher in SH than in WKY rats, and responses to thiobarbiturates differed in aortic strips from SH and WKY rats: contractile responses were greater in WKY than in SH rats, and relaxing effects were greater in SH than in WKY rats. Responses to sodium nitroprusside did not differ in the aortas of SH and WKY rats, but the effects of nifedipine were greater in strips from SH rats than from WKY rats at the age of 10-12 wk. Ca2(+)-induced contractions of strips exposed to Ca2(+)-free media and depolarized by high K+ were inhibited by treatment with thiamylal; the inhibition was greater in SH than in WKY rats. The increase in smooth-muscle relaxation induced by thiobarbiturates in strips from SH rats may be due to increased sensitivity to the Ca2(+)-channel blocking action of thiobarbiturates.

Animals↗
PubMed1990

[Clinical experience with extracorporeal shock wave lithotripsy MFL-5000 for urinary stone].

A Dornier MFL 5000, a new generation extracorporeal shock wave lithotripter, was installed in our hospital and the first Japanese clinical experience has been collected between July and November in 1989. We report our experience with the first 35 patients with 45 stones who were treated in 42 treatments using ESWL. We followed up 3 weeks. No invasive anesthesia was performed except 2 cases of epidural anesthesia. A double J catheter was installed in 2 patients, a ureteral catheter in 4 patients, and PNL was performed in 2 patients before ESWL. We did not use a PNL or a TUL in the postoperative treatment. In the 3 week followed up period, 29 patients (82.9%) were completely free from stone fragments. No serious complications were observed after ESWL. We conclude that the DORNIER MFL 5000 is effective for renal and ureteral stones without serious complications.

Adult↗
PubMed1990

[Craniomandibular disorders management (1) Treatment planning].

Various treatment modalities have been reported in the management of the craniomandibular disorders in the half century after Costen reported his hypothesis on the temporomandibular disorders. Recent advances in the basic sciences such as anatomy, histology, pathology, physiology and clinical trials have brought us to this new era. We have been trying to establish our diagnosis and treatment modalities in the management of the craniomandibular disorders over the past fifteen years. In this series of articles we will describe our present concept. We will first discuss diagnosis and treatment planning. After the diagnosis and initial treatment planning craniomandibular management is usually divided into two phases. Phase I is the treatment of the stomatognathic system especially the temporomandibular joint. Behavioral modification and physical therapy and splint therapy are the most common forms of treatment. Sometimes, surgical treatment is required. Phase II is the compensatory phase of the occlusion consisting of occlusal equilibration, occlusal restorations, orthodontic treatment and gnathic surgery if needed. Another phase we like to add is maintenance. In this phase, home therapy, corrective follow-up and long term observation should be emphasized. The motivation of the patient throughout the management of the craniomandibular disorder (phase I, phase II and the maintenance phase) is essential to reach to a successful result.

Behavior Therapy↗
PubMed1990

[The effect of the local anesthesia to the posterior ramus of the mandible in patients with temporomandibular joint problems].

Some clinicians in North America use anesthetic injections to differentiate the symptoms such as pain and stiffness in the facial area and neck in patients with TMJ problems. However, the effects and area which is influenced have not been studied. The purpose of this study was to study procedures and changes following administration of local anesthesia to the posterior ramus of the mandible. Twenty four patients with TMJ problems were used in this study. 0.5ml of 2% Lidocaine (epirenamine included) was injected into the most painful site upon palpation. The pain upon palpation test (following Krogh-Poulsen's method) was compared before and after 50 minutes. Results of this experiment were: 1) decrease of pain upon palpation was found not only in the site. In many cases subjective pain in the head and neck area was also reduced. 2) A significant reduction was found in the pain upon palpation test in the neck area. A highly significant reduction was seen in the Sterunoclydmastoid muscle only in the injected side. In the masticatory muscles. Also, reduction of pain upon palpation was seen in both lateral, medial pterygoid and digastric muscles in the injected side. 3) Contra side lateral pterygoid muscle and trapezius muscle also registered decreased pain upon palpation. 4) The mean values for the injected site were 5.7mm (S.D. 5.9) below the earlobe and the mean depth from the skin surface to the bony surface were 16.6 mm (S.D. 2.7mm). 5) The peak of the subjective effect were seen in one group in 20 minute later injection (early type) and in the 2nd group the peak were seen after 40 minutes (slowly type). 6) We did not experienced any paralysis of the facial nerve in this study.

Diagnosis, Differential↗
PubMed1990

A clinical study of total cystectomy for transitional cell carcinoma of the urinary bladder.

Fifty six patients with transitional cell carcinoma of the urinary bladder were treated by total cystectomy from January, 1979 through December, 1988. A retrospective study was conducted on 52 patients on whom prognosis could be followed up. There were 40 men and 12 women (male to female ratio: 3.3: 1), between 32 and 79 years old (mean age, 64.1 years old). The overall 1-, 3- and 5-year survival rates were 65.8%, 54.1% and 43.0%, respectively. The 5-year survival rates for patients with low grade (G, I, II) and high grade (G. III) were 41.9% and 42.7%, respectively: with no significant difference in the survival curves between the two groups. The 5-year survival rates according to histopathological stage were 78.9% for patients in low stage, 24.7% in high stage, and the difference in the survival curves between the two groups was statistically significant (P less than 0.001). The mortality in the 21 cases of the 33 high stage cases in which cisplatin was used was 42.9%, with 3- and 5-year survival rates were 53.1% and 36.8%, respectively. In the remaining 12 cases in which cisplatin was not used for post-operative chemotherapy, the mortality in the 12 cases was 83.3%, with 3- and 5-year survival rates of 25.1% and 12.3%, respectively. Thus, the patients who received post-operative chemotherapy showed a better survival rate than those who did not with a significant difference (P less than 0.05). The results of the present study suggest the usefulness of post-operative adjuvant chemotherapy in the high stage case.

Adult↗
PubMed1990

[Clinical evaluation of sultamicillin in the treatment of urinary tract infections].

Sultamicillin, a new semisynthetic oral beta-lactam antibiotic, was evaluated for its antibacteria susceptibility and clinical efficacy against urinary tract infection (UTI), and the following results were obtained. The sensitivity of sultamicillin (SBTPC) on 518 strains of clinical isolates from the urine were tested and compared to ampicillin (ABPC). S. aureus, S. epidermidis, Enterococcus sp., Streptococcus sp., E. coli, K. pneumoniae, K. oxytoca, P. mirabilis, M. morganii and Acinetobacter sp. showed high sensitivity to SBTPC. The antibacterial activity of SBTPC was superior to that of ABPC in most strains and especially more superior in beta-lactamase producing strains. The clinical effectiveness rate on a total of 15 patients with acute uncomplicated cystitis was 93.3% and the eradication rate of causative organisms was 93.3%. On 15 patients with chronic complicated UTI, the clinical effectiveness rate was 73.3% and eradication rate was 76.5%. Side effects (diarrhea) were observed in 3 cases, but this symptom was not severe and soon disappeared. Abnormal laboratory data due to the drug were not observed.

Administration, Oral↗
PubMed1990

[Detection of beta-lactamase-producing strains isolated from urinary tract and their drug susceptibility].

A total of 518 bacterial strains isolated from the urine of patients with various urological diseases in our Urological Department between November, 1987 and February, 1989 were studied for their beta-lactamase production and susceptibility to various antimicrobial agents was determined. beta-lactamase activity was determined by the acidometry disc method. There were 241 gram-positive cocci, 276 of gram-negative rods and 1 Neisseria gonorrhoeae. Thirty-four percent of the gram positive and 76.3% of gram negative rods produced beta-lactamase. S. aureus (81.3%), S. epidermidis (65.1%) in gram-positive cocci, E. cloacae (100%), S. marcescens (100%), C. freundii (100%), P. aeruginosa (97.2%), P. Rettgeri (88.9%), E. gergoviae (85.7%), K. oxytoca (84.6%), M. morganii (81.8%) and E. coli (69.0%) in gram-negative rods produced beta-lactamase at a higher rate. beta-lactamase produced by gram-positive cocci was entirely penicillinase, and that produced by gram-negative rods only penicillinase in 4.0%, only cephalosporinase in 44.2% and both in 25.4%. In S. aureus and S. epidermidis, the isolated rate of strains resistant to ampicillin (p less than 0.01) and piperacillin (p less than 0.05) in the beta-lactamase producing strains was significantly higher than that in the beta-lactamase non-producing strains. In E. coli, the isolation rate of strains resistant to ampicillin and piperacillin in the penicillinase-producing strains was significantly higher than in the penicillinase non-producing strains (p less than 0.01). But both cephalosporinase-producing strains and beta-lactamase non-producing strains showed high susceptibility to cephalothin. These results suggest that the penicillinase might present a clinical problem in the treatment of urinary tract infections by S. aureus, S. epidermidis and E. coli.

Anti-Bacterial Agents↗
PubMed1989

Cardiopulmonary responses to the tracheobronchial suction with a fiberoptic bronchoscope during and after anesthesia.

The cardiopulmonary responses to endobronchial suction with a fiberoptic bronchoscope (FOB suction) during and after anesthesia were compared in 12 patients underwent elective surgeries. FOB suction for 1 mm was performed during enflurane anesthesia (1.5% enflurane in oxygen) with muscle relaxant (anesthetized stage) and after anesthesia during spontaneously breathing of oxygen (awake stage). FOB suction lowered PaO2 to a greater extent in the awake than in the anesthetized stage. Mean PaO2 decreased from 414 to 111 torr in the awake and from 447 to 333 in the anesthetized stage. During suction, PaCO2 slightly increased in both stages. In response to FOB suction, heart rate increased significantly in the awake stage (P < 0.001), while mean blood pressure increased significantly in the anesthetized stage (P < 0.01). These findings indicate that the cardiopulmonary responses to FOB suction for 1 min during and after anesthesia differed. The procedure might be less dangerous during anesthesia.

Journal Article↗
PubMed1989

A graphic comparison of mandibular border movements generated by various articulators. Part II: Results.

A method was described in Part I in which mandibular border movements of a subject can be compared with the movements generated by various articulators (fully adjustable Denar SE and semiadjustable Denar Mark II) by using an electronic pantograph, the Pantronic. The mean values of 12 sets of plots from this device were calculated and graphs were generated. For the subject studied, differences were detected by the Pantronic pantograph between human border movements and those generated by each articulator and method of adjusting it. In the horizontal table, the semiadjustable articulator without immediate side shift always showed the potential of greater errors, especially as excursions started. When the semiadjustable instrument was programmed with immediate side shift, its movements were comparable with the fully adjustable articulator. Neither articulator exactly simulated the subjects' movements.

Dental Articulators↗
PubMed1989

The contractile responses of isolated dog cerebral and extracerebral arteries to oxybarbiturates and thiobarbiturates.

In helical strips of dog cerebral, coronary, mesenteric, renal, and femoral arteries, the addition of thiamylal and thiopental, 10(-5) to 10(-3) M, caused a dose-related contraction; the contraction was significantly more intense in cerebral than in extracerebral arteries. Secobarbital caused a slight contraction only in the cerebral artery. In contrast, pentobarbital did not produce a contraction in any artery studied. The thiamylal-induced contraction was not affected by treatment with phentolamine, diphenhydramine, or cinanserin but was attenuated by treatment with Ca entry blockers, such as nifedipine or diltiazem. In the cerebral artery soaked in Ca++-free media for 60 min, the addition of Ca++ produced triphasic responses; a transient contraction followed by a relaxation and a slowly developing, persistent contraction. The persistent contraction was potentiated by 10(-4) M thiamylal but abolished at 10(-3) M. In the mesenteric artery soaked in Ca++-free media, the addition of Ca++ produced only a slight contraction, which was potentiated by thiamylal (10(-4) and 10(-3) M). It is concluded that thiobarbiturates are more potent vasoconstrictors than oxybarbiturates and that the barbiturates produce greater contraction in cerebral arteries than in extracerebral arteries. The thiamylal-induced contraction appears to be associated mainly with influx of Ca++ from extracellular fluids.

Animals↗
PubMed1989

Intravenous administration of isosorbide dinitrate attenuates the pressor response to laryngoscopy and tracheal intubation.

In order to evaluate the effect of isosorbide dinitrate (ISDN), administered as a bolus intravenous injection, on the circulatory response to tracheal intubation, mean arterial pressure (MAP), and heart rate (HR) in response to laryngoscopy for 30 s followed by tracheal intubation were compared in patients not receiving ISDN (control) and receiving 40 micrograms/kg or 80 micrograms/kg of ISDN 45 s before starting laryngoscopy. Each group consisted of 10 patients undergoing elective surgery. Forty-five seconds after starting laryngoscopy, MAP was significantly (P less than 0.01) lower in patients receiving 80 micrograms/kg ISDN than in those receiving no or 40 micrograms/kg ISDN. HR increased to a similar extent in the three groups. These results indicate that a bolus injection of ISDN (80 micrograms/kg) is a simple, practical and highly effective means of attenuating the hypertensive response to direct laryngoscopy and tracheal intubation.

Adult↗