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T Fukada

Publications and source records attributed to T Fukada.

At least 37 records · Page 2Linked to original sources
PubMed1996

A central role for Stat3 in IL-6-induced regulation of growth and differentiation in M1 leukemia cells.

Interleukin-6 (IL-6) induces either differentiation or growth of a variety of cells. Little is known about the molecular basis of this cellular decision. The family of signal transducer and activator of transcription (Stat) proteins are involved in signaling through a variety of cytokine and growth factor receptors, although their biological roles have not been established. To address whether Stat proteins play roles in IL-6-induced growth or differentiation, we introduced two types of mutant Stat3 acting in a dominant-negative manner into M1 leukemic cells which respond to IL-6 with growth arrest and terminal differentiation. We show that dominant-negative forms of Stat3 inhibited both IL-6-induced growth arrest at G(0)/G1 and macrophage differentiation in the M1 transformants. Blocking of Stat activation resulted in inhibition of IL-6-induced repression of c-myb and c-myc. Furthermore, IL-6 enhanced the growth of M1 cells primarily through shortening the length of the G1 period when Stat3 was suppressed. Thus IL-6 generates both growth-enhancing signals and growth arrest- and differentiation-inducing signals at the same time. Stat3 may be a key molecule which determines the cellular decision from cell growth to differentiation in M1 cells.

Animals↗
PubMed1996

Differentiation and growth arrest signals are generated through the cytoplasmic region of gp130 that is essential for Stat3 activation.

Interleukin-6 (IL-6) induces growth arrest and macrophage differentiation through its receptor in a murine myeloid leukaemic cell line, M1, although it is largely unknown how the IL-6 receptor generates these signals. By using chimeric receptors consisting of the extracellular domain of growth hormone receptor and the transmembrane and cytoplasmic domain of gp130 with progressive C-terminal truncations, we showed that the membrane-proximal 133, but not 108, amino acids of gp130 could generate the signals for growth arrest, macrophage differentiation, down-regulation of c-myc and c-myb, induction of junB and IRF1 and Stat3 activation. Mutational analysis of this region showed that the tyrosine residue with the YXXQ motif was critical not only for Stat3 activation but also for growth arrest and differentiation, accompanied by down-regulation of c-myc and c-myb and immediate early induction of junB and IRF1. The tight correlation between Stat3 activation and other IL-6 functions was further observed in the context of the full-length cytoplasmic region of gp130. The result suggest that Stat3 plays an essential role in the signals for growth arrest and differentiation.

Amino Acid Sequence↗
PubMed1996

Two signals are necessary for cell proliferation induced by a cytokine receptor gp130: involvement of STAT3 in anti-apoptosis.

gp130 is a common signal transducer for the interleukin-6-related cytokines. To delineate the gp130-mediated growth signal, we established a series of pro-B cell lines expressing chimeric receptors composed of the extracellular domain of the granulocyte colony-stimulating factor receptor and the transmembrane and cytoplasmic domains of gp130. The second tyrosine (from the membrane) of gp130, which was required for the tyrosine phosphorylation of SHP-2, its association with GRB2, and activation of a MAP kinase, was essential for mitogenesis, but not for anti-apoptosis. On the other hand, the tyrosine in the YXXQ motifs essential for STAT3 activation was required for bcl-2 induction and anti-apoptosis. Furthermore, dominant-negative STAT3 inhibited anti-apoptosis. These data demonstrate that two distinct signals, mitogenesis and anti-apoptosis, are required for gp130-induced cell growth and that STAT3 is involved in anti-apoptosis.

Animals↗
PubMed1996

[Accuracy of a pulse oximeter during hypoxia].

The accuracy of the pulse oximeter was examined in hypoxic patients. We studied 11 cyanotic congenital heart disease patients during surgery, and compared the arterial oxygen saturation determined by both the simultaneous blood gas analysis (CIBA-CORNING 288 BLOOD GAS SYSTEM, SaO2) and by the pulse oximeter (DATEX SATELITE, with finger probe, SpO2). Ninty sets of data on SpO2 and SaO2 were obtained. The bias (SpO2-SaO2) was 1.7 +/- 6.9 (mean +/- SD) %. In cyanotic congenital heart disease patients, SpO2 values were significantly higher than SaO2. Although the reason is unknown, in constantly hypoxic patients, SpO2 values are possibly over-estimated. In particular, pulse oximetry at low levels of saturation (SaO2 below 80%) was not as accurate as at a higher saturation level (SaO2 over 80%). There was a positive correlation between SpO2 and SaO2 (linear regression analysis yields the equation y = 0.68x + 26.0, r = 0.93). In conclusion, the pulse oximeter is useful to monitor oxygen saturation in constantly hypoxic patients, but the values thus obtained should be compared with the values measured directly when hypoxemia is severe.

Adolescent↗
PubMed1996

[A patient with Cornelia de Lange syndrome with difficulty in orotracheal intubation].

We experienced a difficult orotracheal intubation in a patient with Cornelia de Lange syndrome. The patient was an eight-year-old girl with Cornelia de Lange syndrome, cleft palate and tetralogy of Fallot who underwent emergency hemicolectomy for strangulation ileus. Orotracheal intubation using a Macintosh laryngoscope was unsuccessful. However, intubation using an endotracheal tube through the laryngeal mask airway with a fiberoptic bronchoscope was successful. The patient's condition was stable during both intubation and operation. In conclusion, we must be careful on endotracheal intubation of patients with congenital anomalies.

Anesthesia, General↗
PubMed1996

[Bacterial contamination of anesthesiologists' hands and the efficacy of handwashing].

The purpose of this study was to examine bacterial contamination, especially by transient skin flora, that were on the hands of trainee and diplomate anesthesiologists during general anesthesia as well as to evaluate the efficacy of washing hands with running water or with three alcohol based antiseptic solutions using a modified glove juice method. The bacterial counts on the anesthesiologists' hands were 3.21 +/- 0.66 [log10 (mean +/- SD)] during induction, 255 +/- 1.15 during maintenance of anesthesia, 2.67 +/- 1.10 during extubation and 3.57 +/- 0.74 at the end of anesthesia. The diplomates' hands were more contaminated than those of the trainees during both intubation and extubation. Washing hands with running water or antiseptic solutions was effective to reduce bacterial contamination, but there was no disinfectant effect of antiseptic solutions against the bacteria that adhered to the hands after drying those solutions. Therefore to prevent nosocomial infection, anesthesiologists should wash their hands with running water or the antiseptic solution after each contact.

Anesthesia, General↗
PubMed1995

Activation of Fes tyrosine kinase by gp130, an interleukin-6 family cytokine signal transducer, and their association.

gp130 is a signal-transducing subunit of receptors for the interleukin-6 (IL-6)-related cytokine subfamily including IL-6, leukemia inhibitory factor, oncostatin M, IL-11, and ciliary neurotrophic factor, indicating that gp130-mediated signals are involved in the immune response, hematopoiesis, inflammation, and endocrine and nervous system activity. We previously showed that gp130 stimulation rapidly activates Jak, Btk, and Tec tyrosine kinases, all of which constitutively associate with gp130. To further elucidate intracellular signal transduction through gp130, we examined the possible involvement of another nonreceptor tyrosine kinase, p92c-fes (Fes). We showed that gp130 stimulation rapidly induced tyrosine phosphorylation of Fes and actually activated its kinase activity in hematopoietic lineage cells. Furthermore, Fes associated with gp130 independently of ligand stimulation like Jak, Btk, and Tec tyrosine kinases. These results indicate that multiple nonreceptor tyrosine kinases are involved in the gp130-mediated signal transduction pathway. Because both gp130 and Fes are expressed not only in hematopoietic lineage cells but also in heart and nerve cells, Fes may play a role in signal transduction through gp130 in these tissues.

Animals↗
PubMed1995

Association and activation of Btk and Tec tyrosine kinases by gp130, a signal transducer of the interleukin-6 family of cytokines.

Interleukin-6 (IL-6), leukemia inhibitory factor, oncostatin M, IL-11, and ciliary neurotrophic factor constitute the IL-6 family of cytokines and play important roles in hematopoiesis, immune response, and nervous system. The receptors for the IL-6 family of cytokines share gp130 through which signals are generated, although the cytoplasmic region of gp130 does not contain any catalytic domain. In this study we show that in addition to Jak family tyrosine kinase, the stimulation of gp130 by IL-6 plus soluble IL-6 receptor alpha induced the activation of Btk and Tec tyrosine kinases, whereas IL-3 and granulocyte colony-stimulating factor activated Tec but not Btk in a pro-B cell line. Furthermore, both Btk and Tec kinases were associated with gp130 without the ligand stimulation. Because Btk is a critical tyrosine kinase for B lymphopoiesis and Tec is considered to be involved in hematopoiesis, the results suggest the involvement of gp130-Btk-Tec signal pathway in early lymphohematopoiesis.

Agammaglobulinaemia Tyrosine Kinase↗
PubMed1995

Characterization of rat N-acetylglucosaminyltransferase I expressed in Escherichia coli.

The catalytic domain (sGnT-I) of rat liver N-acetylglucosaminyl-transferase I (GnT-I) was expressed in Escherichia coli. Lysates from pETsGnT-I transformants contained a prominent protein species of 46 kDa with which a significant GnT-I activity was associated. To purify the relevant enzyme, we constructed cDNAs encoding sGnT-ICH and sGnT-INH, which had six additional histidine residues as an affinity tag at the C-terminal and the N-terminal of sGnT-I, respectively, and introduced them into E. coli cells for expression. sGnT-INH was purified and its enzymatic properties were examined.

Animals↗
PubMed1995

[Difficult adult airway and endotracheal intubation].

In 1984, Cormack and Lehane defined laryngoscopic view in four grades. As the view worsens, the difficulty of intubation may increase but it is not clear. In this study, we examined the endotracheal intubation techniques to the grade III or IV airways. Some 48 patients were determined as grade III and IV. In 26 patients the conventional endotracheal intubation technique (conventional technique) was selected. In 20 patients endotracheal intubation was performed over the gum-elastic bougie (bougie technique). In two patients laryngeal mask airway, fiberoptic bronchoscope and handmade flexible guide tube were used as aids to endotracheal intubation (guide technique). Nineteen patients with conventional technique and 6 patients with bougie technique required the external laryngeal pressure. In conclusion, the grade III or IV airways were not always difficult to intubate. But when the conventional technique failed, the gum-elastic bougie or laryngeal mask airway was a fairly useful aid to endotracheal intubation. Moreover our handmade flexible guide tube made the intubation through the laryngeal mask airway safe and reliable.

Adult↗
PubMed1993

Transcriptional regulation of Bacillus thuringiensis subsp. israelensis mosquito larvicidal crystal protein gene cryIVA.

The cryIVA gene encodes a component of the delta-endotoxin of Bacillus thuringiensis subsp. israelensis. By S1 nuclease mapping and primer extension analysis, we have identified the transcriptional initiation site of cryIVA. The transcriptional activity from the promoter was detected only for the sporulating cells more than 3 h after onset of the stationary phase. Upstream from the cryIVA transcriptional initiation site was found a nucleotide sequence partially homologous to the promoter consensus sequence for the E sigma E holoenzyme of Bacillus subtilis. Thus, it was strongly suggested that the identified cryIVA promoter, like some other crystal protein gene promoters, was under the control of sigma 35, the B. thuringiensis homolog of sigma E.

Amino Acid Sequence↗
PubMed1993

Direct determination of opium alkaloid-bovine serum albumin conjugate by matrix-assisted laser desorption/ionization mass spectrometry.

Opium alkaloids (thebaine, codeine and morphine) have been conjugated with bovine serum albumin (BSA) to give individual antigen conjugates which are analyzed by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. It became clear that 9 molecules of thebaine were contained in a thebaine-BSA conjugate. Codeine and morphine contents in individual conjugates were determined to be 12 and 6 molecules, respectively.

Codeine↗
PubMed1993

Platelet abnormalities in a dog suffering from gangrenous mastitis by Staphylococcus aureus infection.

Severe gangrenous mastitis due to Staphylococcus aureus infection was diagnosed in a 7 year-old intact female beagle which was presented with swelling of mammary glands after dystocia. Leukocytosis (25,200-48,600/microliters), decreased platelets (107,000-179,000/microliters), and abnormal platelet pattern continued during the critical condition. Consistent with platelet pattern, large platelets were observed in the blood smear. The number of leukocytes and platelets rapidly returned to normal during treatment, and the platelet pattern was also restored. The number and pattern of platelet may provide a clue for the evaluation of the clinical condition and/or severity of the lesions in the dog with mastitis.

Animals↗
PubMed1993

[Changes in respiration and hemodynamics during open heart surgery without blood transfusion].

The changes in respiration and hemodynamics during open heart surgery were studied in 25 patients undergoing coronary artery bypass grafting without blood transfusion. The respiratory and circulatory parameters were measured at the time of anesthetic induction and after cardiopulmonary bypass (CPB). The values after CPB were compared with those at the time of anesthetic induction. The values of HR, CI, SVI and mPAP increased, and the values of mAP, SVRI and PVRI decreased after CPB. The PaO2, BE and pH decreased but PaCO2, A-aDO2 and QS/QT increased after CPB. Although VO2I and DO2I increased after CPB, OER (VO2I/DO2I) was unchanged. Arterial lactate, pyruvate and cortisol levels increased after weaning from CPB. Hemodynamics during open heart surgery without blood transfusion showed hyperdynamic state after CPB. Hypoxia was not evident in the peripheral tissue. This suggests that the depression of the oxygen delivery with hemodilution is compensated by hyperdynamic circulation. Coronary artery bypass grafting without blood transfusion seems to offer no clinical problems.

Blood Transfusion↗
PubMed1993

[Evaluation of skin temperature of patients under spinal anesthesia during cesarean section].

Temperature changes of the first finger and toe were evaluated in patients under spinal anesthesia. One hundred and thirty female patients who were to undergo cesarean section were selected for this study. During spinal anesthesia the changes in skin temperature were classified in three patterns. The first pattern showed a rise of the first finger and toe temperature just after intrathecal injection of 0.3% dibucaine (hand and foot type, n = 77). The second pattern showed only a rise of the first toe temperature (foot type, n = 55), and the third pattern showed no change in the first finger and toe temperature (unchanged type, n = 3). The results of cold description tests were T5 +/- 2 (mean +/- SD) in hand and foot type, T8 +/- 2 in foot type and L1 +/- 6 in unchanged type. The skin temperature pattern was affected by the position of the patient. When the patients were placed in a head down position, 38 cases of foot type showed a rise of the first finger temperature, and 1 case of unchanged type showed a rise of the first finger and toe temperature. In these cases the operative procedure was done under spinal anesthesia. The remaining 4 cases of foot type and 2 cases of unchanged type needed another anesthetic method. In cesarean section under spinal anesthesia, skin temperature pattern of hand and foot type seems desirable. Simultaneous monitoring of hand and foot (first fingertip temperature) seems to be useful to evaluate the height of spinal anesthesia.

Adult↗
PubMed1993

[Comparison of sevoflurane and halothane in pediatric anesthesia].

In the present study we compared sevoflurane (group S) and halothane (group F) as used in pediatric endotracheal anesthesia. The subjects consisted of 100 pediatric patients, each 50 in group S and F, most of whom underwent otorhinolaryngological surgery. Anesthesia was induced with nitrous oxide-oxygen-sevoflurane (GOS) (S 3-5%) or nitrous oxide-oxygen-halothane (GOF) (F 1.5-2.5%), and maintained with GOS (S 2-3%) or GOF (F 1.0-1.5%). In comparing the groups with respect to anesthetic induction, group S required 2.1 min for the loss of consciousness, 6.1 min for ocular fixation and 9.7 min for completion of intubation, while in group F the time intervals for the above items were 2.4, 4.9 and 10.2 min, respectively. No significant differences were found between the two groups except in the loss of consciousness and ocular fixation. Comparison of the groups during maintenance of anesthesia revealed no significant differences, although pulse rate and diastolic blood pressure increased in both groups. When the groups were compared for awakening from anesthesia, group S required 10.1 min for awakening and 11.9 min for extubation, while in group F the time was 13.0 min and 15.4 min, respectively. These values were significantly different. The present study demonstrated that sevoflurane anesthesia is rapid in both induction and awakening as compared with halothane anesthesia, and that GOS inhalation anesthesia with single use of sevoflurane can be usefully applied to pediatric endotracheal anesthesia.

Anesthesia, Inhalation↗
PubMed1993

[Relation between fingertip temperature pattern and epidural puncture site during epidural anesthesia combined with general anesthesia].

We are employing fingertip temperature monitoring to estimate the spread of epidural anesthesia in patients who received combined epidural and general anesthesia. In this study we examined the relation between fingertip temperature pattern and epidural puncture site. One hundred patients scheduled for elective digestive tract surgery were studied. They were divided into three groups according to the epidural puncture sites as follow; Group 1, T7-9 (n = 26); group 2, T9-12 (n = 48); and group 3, T12-L5 (n = 26). Fingertip temperature was determined by Anritsu thermocouples. These probes were attached to the thumb and the big toe (hand and foot fingertip). The changes of these temperatures were classified to four types. In type 1, the hand fingertip temperatures were elevated after administration of the local anesthetics. In type 2, both hand and foot fingertip temperatures were elevated. In type 3, the foot fingertip temperature was elevated. In type 4, the hand and foot fingertip temperatures were unchanged. In group 1, we found 10 cases of type 1, 13 cases of type 2 and 3 cases of type 3. In group 2; 15, 22, 11 cases respectively. In group 3; 1, 16 cases respectively and 1 case in type 4. In group 1 and 2, the type 1 temperature pattern was observed more than in group 3 (P < 0.01). And in group 3, the type 3 temperature pattern was observed more than in group 1 and 2 (P < 0.01). We found no intergroup difference in type 2 pattern. But there were some exceptions.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Epidural↗