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T Kitajima

Publications and source records attributed to T Kitajima.

At least 37 records · Page 2Linked to original sources
PubMed2000

Propofol prevents lipid peroxidation following transient forebrain ischemia in gerbils.

PURPOSE: To ascertain whether propofol prevents lipid peroxidation on delayed neuronal death induced by transient forebrain ischemia in the hippocampal CA1 subfield in gerbils. METHODS: Forty gerbils were randomly assigned to five groups: Group I, control, sham operation treated with physiological saline solution (PSS); Group II, ischemia/reperfusion treated with PSS; Group III, ischemia/reperfusion treated with 50 mg x kg(-1) propofol; Group IV, ischemia/reperfusion treated with 100 mg x kg(-1) propofol; Group V, ischemia/reperfusion treated with 150 mg x kg(-1) propofol. Transient forebrain ischemia was induced by occluding the bilateral common carotid arteries for four minutes under N2O/O2/halothane anesthesia after propofol or PSS. Five days later, the cerebrum was removed and each forebrain was cut into two including the hippocampus. Lipid peroxidation was determined using the production of malondialdehyde (MDA), and histopathological changes in the hippocampal CA1 subfield were examined. RESULTS: In group II, the pyramidal cells were atrophic and pycnotic; vacuolation and structural disruption of the radial striated zone was observed. In the other four groups, these changes were not observed. Degenerative ratios of pyramidal cells were: Group I: 4.9 +/- 2.3, Group II: 94.1 +/- 4.5 (P < 0.01), Group III: 12.5 +/- 5.7, Group IV: 11.0 +/- 4.6, Group V: 9.6 +/- 4.9%. Production of MDA was: Group I: 83 +/- 22, Group II: 198 +/- 25 (P < 0.01), Group III: 153 +/- 39, Group IV: 113 +/- 34, Group V: 106 +/- 27 nmol x g(-1) wet tissue. CONCLUSION: Propofol attenuated delayed neuronal death by preventing lipid peroxidation induced by transient forebrain ischemia in the hippocampal CA1 subfield in gerbils.

Animals↗
PubMed2000

Tauroursodeoxycholate and cholestyramine enhance biliary carcinogenesis in hamsters.

The aim of this study was to examine whether tauroursodeoxycholate (TUDC) and cholestyramine resin (CR) enhance biliary carcinogenesis in the hamster model. A cholecystoduodenostomy with dissection of the extrahepatic bile duct on the distal end of the common duct was performed on Syrian hamsters. The hamsters were then divided randomly into 3 groups: control group, TUDC-treated group, and CR-treated group. All animals received N-nitrosobis(2-oxopropyl)amine (BOP) to initiate pancreaticobiliary cancer. The experiment was terminated at week 16 and the number of neoplastic lesions was counted microscopically. In the TUDC group, the intrahepatic biliary carcinogenesis was more accelerated than that observed in the control group, but no promoting effect was seen in the pancreas, gallbladder, or extrahepatic bile duct. In the CR group, both the intrahepatic biliary and the gallbladder carcinogenesis were inhibited compared with that observed in the control group and the TUDC group. TUDC enhanced the intrahepatic bile duct carcinogenesis, whereas CR inhibited both the intrahepatic bile duct and the gallbladder carcinoma. Bile acids were suggested to promote biliary carcinoma in the hamster model.

Administration, Oral↗
PubMed2000

Cremasteric reflex test as an objective indicator of spinal anaesthesia.

We studied 100 men who were scheduled for urological surgery (Group 1) and another 50 men for orthopaedic surgery (Group 2). We attempted to anaesthetise both sides of the lower body in Group 1 and to anaesthetise one leg in Group 2 by injecting 0.3% hyperbaric dibucaine intrathecally. The presence or absence of the cremasteric reflex and loss of sensation to pinprick higher than the first lumbar dermatome were examined by two researchers who were blind to each other's results. In Group 1, both the reflex and the pinprick sensation were always absent bilaterally 5 min after intrathecal injection. In Group 2, in 23 of 50 patients the reflex had become absent bilaterally; in all these patients, bilateral sensory loss was detected. In the remaining 27 patients, both the reflex and the pinprick sensation were absent on the operation side, whereas both were present on the nonoperation side. Sensitivity, specificity and positive or negative predictive value for the cremasteric reflex were all 100%. Disappearance of the cremasteric reflex is a simple objective indicator of spinal anaesthesia at the first lumbar dermatome. This test may be useful in patients who cannot give reliable answers to conventional tests, such as the pinprick test.

Adult↗
PubMed2000

Airway obstruction during general anaesthesia in a child with congenital tracheomalacia.

Fibreoptic bronchoscopy is often used to diagnose tracheomalacia under local anaesthesia. However, in children, general anaesthesia may be required due to difficulty in obtaining co-operation. A 1-yr-old girl with a suspected congenital tracheomalacia was scheduled for diagnostic fibreoptic bronchoscopy. During induction of anaesthesia by inhalation of increasing concentration of sevoflurane, spontaneous breathing became irregular and a partial airway obstruction occurred. Because vecuronium relieved the airway obstruction, the airway was managed using a laryngeal mask. No further airway obstruction occurred during fibrescopy under controlled ventilation, but when spontaneous breathing resumed, marked airway obstruction occurred. The trachea was intubated immediately. Caution is required to manage the airway without tracheal intubation during general anaesthesia in the patient with tracheomalacia.

Airway Obstruction↗
PubMed2000

Differential distribution of spicule matrix proteins in the sea urchin embryo skeleton.

Spicule matrix proteins are the products of primary mesenchyme cells, and are present in calcite spicules of the sea urchin embryo. To study their possible roles in skeletal morphogenesis, monoclonal antibodies against SM50, SM30 and another spicule matrix protein (29 kDa) were obtained. The distribution of these proteins in the embryo skeleton was observed by immunofluorescent staining. In addition, their distribution inside the spicules was examined by a 'spicule blot' procedure, direct immunoblotting of proteins embedded in crystallized spicules. Our observations showed that SM50 and 29 kDa proteins were enriched both outside and inside the triradiate spicules of the gastrulae, and also existed in the corresponding portions of growing spicules in later embryos and micromere cultures. The straight extensions of the triradiate spicules and thickened portions of body rods in pluteus spicules were also rich in these proteins. The SM30 protein was only faintly detected along the surface of spicules. By examination using the spicule blot procedure, however, SM30 was clearly detectable inside the body rods and postoral rods. These results indicate that SM50 and 29 kDa proteins are concentrated in radially growing portions of the spicules (normal to the c-axis of calcite), while SM30 protein is in the longitudinally growing portions (parallel to the c-axis). Such differential distribution suggests the involvement of these proteins in calcite growth during the formation of three-dimensionally branched spicules.

Animals↗
PubMed2000

New technologies to prevent and treat contact hypersensitivity responses.

Allergic contact dermatitis is a common inflammatory skin disease caused by T cells that recognize environmental and industrial allergens (i.e., haptens). Langerhans' cells (LC), which are skin-specific and "immature" members of the dendritic cell (DC) family of antigen-presenting cells, play crucial roles in the induction of contact hypersensitivity (CH) responses. Upon exposure to haptens, LC migrate from the epidermis to draining lymph nodes, mature into T cell-stimulatory DC, and activate hapten-reactive T cells. Therefore, CH responses should be preventable at the sensitization phase by interfering with one of these changes that occur in LC. Our objective is to develop new technologies for the prevention and treatment of allergic contact dermatitis. In this article, we will introduce three technologies that we have recently developed. First, using a phage display strategy, we have identified a 12-mer peptide (termed "peptide 1") that binds and blocks the function of hyaluronan (HA), which is known to serve as an adhesive substrate for LC migration. Local injection of peptide 1 in mice before topical application of DNFB blocked almost completely the emigration of LC from the epidermis to the draining lymph node, where antigen presentation takes place. Peptide 1 represents a new strategy that is designed to inhibit the initial event of CH. Second, we have established an in vitro experimental system to study the terminal maturation of LC during antigen-specific interaction with T cells. This experimental system, which employs a long-term LC line and T cell clones, should provide a unique tool for the identification of new immunosuppressive agents that block LC terminal maturation selectively. Finally, under the hypothesis that LC, which are engineered to overexpress a death ligand, would deliver apoptotic signals instead of activation signals to T cells, we created a "killer" LC clone by introducing CD95L cDNA into our long-term LC line XS106. In vivo administration of DNFB-pulsed killer LC into mice, either before or after sensitization, resulted in marked suppression of CH responses to DNFB. The killer LC technology represents an entirely new immunosuppressive therapy that is designed to eliminate only the pathogenic T cells.

Animals↗
PubMed2000

Effects of Ba(2+) on norepinephrine-induced contraction of rat thoracic aorta in vitro.

The aim of this study was to examine the effect of exogenously applied BaCl(2) on the norepinephrine-induced contraction of the rat thoracic aorta. Exogenously applied BaCl(2) (0.3-1 mmol/l) slightly elevated the norepinephrine-induced sustained contraction of the rat thoracic aorta in the absence of nicardipine (1 micromol/l). In the aortic preparation pretreated with nicardipine (1 micromol/l), exogenous BaCl(2) (0.1-3 mmol/l) did not elevate the norepinephrine-induced sustained contraction, but the high concentration of BaCl(2) (10 mmol/l) slightly inhibited the norepinephrine-induced tone. In a Ca(2+)-free Krebs bi- carbonate solution (KBS) containing norepinephrine (1 micromol/l) or a Ca(2+)-free K(+)-rich (60 mmol/l) KBS, exogenously applied BaCl(2) (1-30 mmol/l) caused a sustained contraction of the rat thoracic aorta, and this sustained contraction was completely inhibited by nicardipine (1 micromol/l). Exogenous CaCl(2) (0.1-3 mmol/l) also caused a sustained contraction of the aortic preparation in a Ca(2+)- free KBS containing norephinephrine (1 micromol/l), but such a sustained contraction was partly inhibited by nicardipine (3 micromol/l). These results indicate that Ba(2+) elevates the norepinephrine-induced tone of the rat isolated thoracic aorta by permeating voltage-dependent Ca(2+) channels in the absence of nicardipine, but that Ba(2+) has a minor modification on the norepinephrine-induced sustained contraction of the nicardipine-pretreated preparation.

Animals↗
PubMed2000

Effects of Ba2+ on F&F 96365-sensitive sustained contraction of rat pulmonary artery.

The effects of Ba2+ on receptor-mediated sustained contraction of rat pulmonary artery and guinea-pig oesophageal muscularis mucosae were studied in-vitro. In rat isolated pulmonary artery, sustained contraction induced by noradrenaline (1 microM) was resistant to nicardipine (1 microM), but this same sustained contraction was completely inhibited by SK&F 96365 (30 microM), a blocker of voltage-dependent L-type Ca2+ channels and receptor-activated Ca2+ influx. The SK&F 96365-sensitive sustained contraction induced by noradrenaline (1 microM) may be due primarily to Ca2+ influx through receptor-activated Ca)+ channels resistant to nicardipine. Cumulatively applied BaCl2 (0.1 - 10 mM) increased the noradrenaline (1 microM)-induced sustained contraction of the pulmonary arterial preparation in the absence of nicardipine, but in the presence of nicardipine (1 microM), BaCl2 (0.1 - 3 mM) did not affect this contraction. A higher concentration of BaCl22 (10 mM), however, weakly inhibited the noradrenaline (1 microM)-induced tone. In addition, BaCl2 (3-10 mM) increased the tone induced by KCl (60 mM), and the BaCl2-elevated KCl tone was markedly inhibited by nicardipine (1 microM) treatment. In the guinea-pig isolated oesophageal muscularis mucosae, sustained contraction induced by acetylcholine (3 microM) was resistant to nicardipine (1 microM) but was returned to its basal level by SK&F 96365 (30-60 microM). The SK&F 96365-sensitive, acetylcholine-induced sustained contraction of the oesophageal muscularis mucosae is also likely to link with receptor-activated Ca2+ channels resistant to nicardipine. In contrast to the rat pulmonary artery, cumulatively applied BaC12 (0.3 - 10 mM) inhibited the acetylcholine (3 microM)-induced sustained contraction of the oesophageal muscularis mucosae in a concentration-dependent manner in the presence of nicardipine (1 microM). In conclusion, Ba2+ presumably activates voltage-dependent Ca2+ channels by depolarizing plasma membrane and also passes through voltage-dependent Ca2+ channels to contract the pulmonary artery in the absence of nicardipine, and Ba2+ also has a minor effect on the nicardipine-resistant, SK&F 96365-sensitive sustained contraction induced by noradrenaline in rat isolated pulmonary artery.

Acetylcholine↗
PubMed2000

Quantitative diversity of 67 kda protective antigen among serovar 2 strains of Erysipelothrix rhusiopathiae and its implication in protective immune response.

Mouse monoclonal antibodies (MAbs), raised against the NaOH-extracted antigen of Erysipelothrix rhusiopathiae strain Kyoto (serovar 2), recognized two different epitopes on a single protein of molecular weight 67 kDa. The MAbs were classified as protective or non-protective against strain Fujisawa (serovar 1). In immunoblotting analysis using the MAbs, fifteen wild strains were shown to contain different amounts of 67 kDa protective antigen. Each formalin-killed whole cell vaccine (bacterin) prepared from the fifteen wild strains conferred different levels of protection against strain Fujisawa in mice. Bacterins prepared from wild strains with larger amounts of 67 kDa protective antigen tended to give high levels of antigen-specific antibody and better protection to mice. These results indicate that the amount of 67 kDa protective antigen which influences the induction of protective immune responses may vary substantially among the strains of E. rhusiopathiae (serovar 2).

Animals↗
PubMed2000

[Anesthetic management of a patient with West syndrome].

A 21-year-old female with West syndrome was scheduled for resection of hordeolum. She had an episode of convulsion at three months of age, and was diagnosed as having West syndrome at one year of age. She had epileptic seizures twice a week in spite of administration of phenytoin, clonazepam and sodium valproate. These drugs had been administered till the morning of the surgery. After premedication with atropine 0.25 mg, anesthesia was induced with propofol (12-->10-->8 mg.kg-1.h-1). The tracheal intubation was performed with vecuronium 0.1 mg.kg-1 and anesthesia was maintained with continuous infusion of propofol 6-8 mg.kg-1.h-1 and local infiltration with 1.0% lidocaine 5 ml. We administered phenytoin to prevent epileptic seizures during the surgery. No epileptic seizures occurred perioperatively. We conclude that propofol may be useful for a patient with West syndrome, and we should be careful not to lower the threshold for convulsion during the perioperative period.

Adult↗
PubMed2000

[Anesthetic management of bilateral lung lavage for pulmonary alveolar proteinosis--comparison between sevoflurane and propofol].

A 55-year-old man with pulmonary alveolar proteinosis underwent lung lavage under general anesthesia using sevoflurane three years ago. Although transient hypoxia occurred postoperatively, there were no complications. Because of the recent deterioration of his symptoms, he was rescheduled for lung lavage. Anesthesia was induced with propofol 120 mg and fetanyl 0.2 mg. Vecuronium 7 mg was administered to facilitate tracheal intubation using a double-lumen tube. Anesthesia was maintained with propofol 4 mg.kg-1.h-1. Electrocardiogram, blood pressure, SPO2, EtCO2 and rectal temperature were monitored intraoperatively. We also checked PaO2 when necessary. Although transient hypoxia occurred after the procedure, it receded spontaneously. Since inhalation anesthetics inhibit hypoxic pulmonary vasoconstriction, intravenous anesthetics may be more useful for patients with severe pulmonary alveolar proteinosis.

Anesthesia, General↗
PubMed2000

[Usefulness of laryngeal mask for difficult intubation in a child with congenital laryngeal webs].

We report a case of difficult intubation with congenital laryngeal web. An 11-year-old boy was scheduled for urinary surgery. After anesthetic induction, the anesthesiologist encountered resistance at the vocal cord preventing satisfactory intubation. A size 3 laryngeal mask was immediately inserted, and an adequate airway was obtained. We found a laryngeal web at the vocal cord by bronchoscope inserted thorough the laryngeal mask. The peroperative course was uneventful. Immediately after removal of the laryngeal mask, the patient developed airway obstruction due to sputum and/or laryngeal spasm. The obstruction was relieved through application of positive pressure ventilation and aspiration of the sputum.

Airway Obstruction↗
PubMed2000

[Two cases of extreme hemodilution caused by massive hemorrhage immediately after start of operation].

We describe two cases of extreme hemodilution due to large amounts of fluid infusion for unexpected massive hemorrhage. In both cases, unexpected hemorrhage with difficult hemostasis occurred within 60 min after the start of the operation. For lack of transfused blood, large amounts of fluid infusion using crystalloid and colloid solutions including 5% albumin, plasma expander and lactated Ringer's solution were administered to maintain circulatory blood volume. The hemoglobin concentration and hematocrit had been below 2.0 g.dl-1 and 10% for approximately one hour, respectively. The extreme hemodilution improved by the urgent blood transfusion. In one case, intraoperative autotransfusion with Cell-Saver was performed. In spite of intraoperative extreme hemodilution, their postoperative courses were uneventful. Intraoperative awareness was present in both cases.

Adult↗
PubMed2000

[Damage of a laryngeal mask airway during anesthesia].

A 21-year-old man was scheduled for fixation of a fractured radius and ulna under general anesthesia using a laryngeal mask airway (LM). Anesthesia was induced with propofol 120 mg and fentanyl 0.1 mg. After administration of vecuronium 6 mg, we attempted insertion of the LM (# 5). The first trial was unsuccessful because the tube of the LM was bent in the pharynx. We attempted it again and the LM was successfully inserted. It was connected with the anesthetic circuit, and manual ventilation was started. However, the LM was suddenly broken at the basal part of the tube connector before the start of operation, and it became detached from the anesthetic circuit. Therefore, we removed the remaining LM from the mouth, and inserted a new LM (# 5). The peroperative course was uneventful. We conclude that inspection of a recycled LM is important before using it in order to prevent such an event as the present case.

Adult↗
PubMed2000

[A case of acute urticaria from hydroxyzine hydrochloride used for preanesthetic medication].

We report a case of acute urticaria probably caused by hydroxyzine hydrochloride. A 66-year-old male was scheduled for cardiac cystectomy by thoracic endoscopy. The patient was premedicated with atropine and hydroxyzine intramuscularly 30 min before arrival in the operating room. Abrupt general exanthema was observed when intravenous infusion was started. Although his general condition was stable, the operation was postponed. Three days later, the skin test was performed using several drugs. Only hydroxyzine hydrochloride gave positive result. It is assumed that hydroxyzine hydrochloride may have caused his urticaria.

Acute Disease↗