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M Tsuchida

Publications and source records attributed to M Tsuchida.

At least 91 records · Page 5Linked to original sources
PubMed1997

[Oro-pharyngeal burn during electrodissection of the adenoid and tonsil].

We present a case of oro-pharyngeal burn which occurred during electrodissection of the adenoid and tonsil in a 5-year-old boy. We intubated the patient with an uncuffed spiral tube of appropriate size and noticed a slight gas leak during positive-pressure ventilation. Anesthesia was maintained with a mixture of 60% nitrous oxide, 40% oxygen and 2.5% sevoflurane. During manipulations of the right tonsil, orange-colored flame blew out about 5 cm from the mouth. Fortunately, the patient underwent the operative procedures without any further troubles, recovered fully from the grade 1 burn in the oral mucosa, and was discharged 23 days after surgery. The surgeons speculated that sevoflurane had been ignited. Although it is well known that sevoflurane is nonflammable in the concentration of clinical use, several reports show that sevoflurane is flammable in concentration of 10% under pure oxygen or nitrous oxide. We concluded that this accident was caused by electrocautery-induced ignition of the gauze packed into the larynx under a high concentration of oxygen which leaked through an uncuffed endotracheal tube. We have to bear in mind that any flammable substance may ignite when using electrocautery in a small space such as the mouth under oxygen-rich environment.

Adenoidectomy↗
PubMed1997

A model of human anti-T-cell monoclonal antibody therapy in SCID mice engrafted with human peripheral blood lymphocytes.

A chimeric severe combined immunodeficient mouse engrafted with human peripheral blood (hu-PBL-SCID) model has been developed to test anti-T-cell monoclonal antibody (mAb) effects on systemic symptoms of the host and the survival of human skin grafts. To obtain consistent engraftment without lethal acute graft-versus-host disease (GVHD), SCID mice were pretreated with a combination of total body irradiation (2.5 Gy, day 0) and anti-asialo GM1 (anti-mouse natural killer cell) antiserum (50 micrograms i.p., day 3) before the intraperitoneal injection of 40-50 X 10(6) human PBL on day 4. With this protocol, the engraftment rate was 82% with 5-98% human CD45-positive cells in the peripheral blood. Mortality at 30 days was 0% in the mice bearing 5-50% human cells compared with 70% in those with more than 50%. Using hu-PBL-SCID mice with 5-50% human cells in their peripheral blood, we demonstrated the following results: 1) Human T cells isolated from these mice proliferated in response to immobilized OKT3 stimulation in vitro. 2) Hu-PBL-SCID mice but not normal SCID mice were able to reject human skin grafts in vivo 16-21 days after grafting. 3) Both OKT3 (anti-human CD3 mAb) and T10B9 (anti-human alpha beta T-cell receptor mAb) treatment prevented human skin graft rejection in hu-PBL-SCID mice. 4) OKT3 but not T10B9 induced first dose reactions characterized by hypothermia and hypoactivity which were consistently observed within 90 min of intravenous injection into hu-PBL-SCID mice. 5) Human cytokines were detected in the serum of the hu-PBL-SCID mice treated with anti-T-cell mAbs. The close similarity of these responses to human clinical mAb immunosuppressive therapy suggests that the hu-PBL-SCID mouse model may be an excellent tool for investigating the immunosuppression, side effects, and mechanism of action of agents that are specific for human and higher apes and not reactive with lower animals.

Acute Disease↗
PubMed1996

Characterization of CD4-CD8- T cell receptor alpha beta + T cells appearing in the subarachnoid space of rats with autoimmune encephalomyelitis.

Inflammation of the central nervous system (CNS) in experimental autoimmune encephalomyelitis (EAE) starts in the subarachnoid space (SAS) and spreads later to the adjacent CNS parenchyma. To characterize the nature of lesion-forming T cells in situ in more detail, T cells were isolated from the SAS and their surface phenotype and the nucleotide sequence of the junctional region of the T cell receptor (TCR) was determined and compared with those of the lymph node (LN) and spinal cord (SC) T cells. Characteristically, more than 70% of SAS TCR alpha beta + T cells isolated at the early stage of EAE lacked both CD4 and CD8 molecules, whereas those from LN and SC were either CD4+ or CD8+. Analysis of nucleotide sequences of the junctional region of TCR revealed that T cells bearing a sequence identical to that for encephalitogenic T cell clones were found in both SAS and SC. Furthermore, purified CD4-CD8- T cells expressed CD4 molecules after culture. At the same time, these T cells acquired reactivity to myelin basic protein and induced passive EAE in naive animals after adoptive transfer. Our results suggest that CD4-CD8- T cells in the SAS are precursors of lesion-forming T cells in the SC and that phenotype switching takes place during the process of T cell infiltration into the CNS parenchyma. The double-negative nature of these T cells may explain an escape of encephalitogenic T cells from negative selection in T cell differentiation.

Amino Acid Sequence↗
PubMed1996

Video-assisted thoracic surgery for thorascopic resection of giant bulla.

This report outlines our experience of 6 patients who underwent video-assisted thoracic surgery (VATS) using a linear endoscopic stapler to remove a giant bulla from the lung. Successful treatment with VATS was carried out in 4 patients, but the procedure needed to be changed to a thoracotomy in 2 patients - in one because of difficulty in single-lung ventilation, and in the other, due to a persistent air leak. Thus, we conclude that giant bulla without any associated severe respiratory failure can be an indication for VATS.

Adult↗
PubMed1996

Change in intramural strain distribution in rat aorta due to smooth muscle contraction and relaxation.

Effect of smooth muscle contraction on intramural strain distribution in rat thoracic aorta was investigated with residual strain considered. Short segments sliced from the aortas were cut radially to release residual strain in an aerated Krebs-Ringer solution (37 degrees C). Each segment opened up immediately to form an arc. Opening angle was measured at this point and after smooth muscle contraction and relaxation. The angle increased from 97 +/- 11 degrees (means +/- SE, n = 14) to 153 +/- 14 degrees with the contraction and decreased to 68 +/- 9 degrees with the relaxation, indicating increase in residual strain with smooth muscle contraction. Intramural strain distribution at various pressures was calculated from the opening angle and pressure-diameter relations of the aortas. Strain distribution was almost uniform at 55 mmHg under smooth muscle relaxation, whereas this pressure exceeded 200 mmHg because of the increase in residual strain and decrease in vessel diameter under smooth muscle contraction. These results suggest aortic smooth muscle may change its contractile state through myogenic response to keep intramural strain distribution uniform against temporary change in blood pressure and thus maintain mechanical homeostasis in the aortic wall.

Animals↗
PubMed1996

Frequency and clinical significance of the MLL gene rearrangements in infant acute leukemia.

We have analyzed the frequency and clinical significance of the MLL gene rearrangements in 42 cases of infant acute leukemias; including 37 cases of acute lymphoblastic leukemia (ALL) and five cases of acute myeloid leukemia (AML). MLL gene rearrangements were found in 27 of the 37 ALL cases (73 percent), and in all five AML cases. Cytogenetic studies showed 11q23 abnormalities in 24 of 27 ALL cases with MLL gene rearrangements. MLL gene rearrangements were significantly correlated with absence of CD10 expression and poor prognosis, but not with age under 6 months, hyperleukocytosis, myeloid-associated antigen expression, or CNS leukemia. The 3-year overall survival rate for ALL cases with MLL gene rearrangements was 5.3 +/- 5.2 percent, compared with 88.9 +/- 10.5 percent for cases with germline MLL (P=0.0001). Absence of CD10 expression was also associated with poor prognosis (9.9 +/- 6.6 percent vs 85.7 +/- 13.2 percent, P = 0.0003). Of the five AML cases, three have remained alive for 27 months to 67 months. These findings suggest that infant ALL with MLL gene rearrangement is strongly associated with poor prognosis. We consider that infant ALL should be treated on different chemotherapy protocols according to the presence or absence of MLL gene rearrangement.

Antigens, CD↗
PubMed1996

The two-fire, one-cartridge stapling method using a modified Endo-GIA.

The endoscopic stapler (Endo-GIA) was designed to divide tissue between two triple-stapled lines. The endoscopic surgeon frequently encounters situations where only stapling is required. Kirby described a staple closure method that uses a knifeless Endo-GIA cartridge. This method, although useful, has the problem of the modified Endo-GIA unit locking. Therefore, we devised a new technique for endoscopic stapling that involves two consecutive staplings using one cartridge without cutting. This method requires modification of the Endo-GIA system by removing the safety-lock system. In addition to enabling endoscopic stapling techniques without the risk of locking, the method can effect a significant cost savings.

Endoscopy↗
PubMed1995

Long-term survival of cardiac allografts in rats treated before and after surgery with monoclonal antibody to CD2.

The rejection of a transplanted allograft is dependent on T cell activation, which requires T cell receptor engagement by antigen and costimulatory signals delivered by T cell surface molecules such as CD2. Anti-CD2 mAbs have been shown to suppress cell-mediated immunity. The effects of anti-CD2 mAbs OX34 and OX54 on rejection of BN (RT1n) rat hearts transplanted heterotopically to LEW (RT1l) rats were investigated. Administration of OX34 (7 mg/kg/day i.p.), either for 3 consecutive days immediately before or 8 consecutive days immediately after transplantation induced indefinite allograft survival (median survival time: 7, > 150, and > 150 days for control, preoperative treatment, and postoperative treatment, respectively). In contrast, pre- or postoperative treatment with OX54 (40 mg/kg/day) prolonged median survival time to only 28 and 11 days, respectively. Administration of OX34 or OX54 to naive rats induced a transient depletion of T cells in the peripheral immune organs. In vitro studies revealed that whereas OX54 had no effect on the allogeneic mixed lymphocyte reaction, OX34 partially inhibited both the allogeneic mixed lymphocyte reaction, in an IL-2-reversible manner, and T cell proliferation in response to immobilized mAb to either the T cell receptor or CD3. OX34-treated rats in which the cardiac allograft had survived > 100 days accepted a second heart from the donor strain. Treatment with OX34 induced an alloantigen-unresponsive state in T cells. These results suggest that treatment with an appropriate anti-CD2 mAb, especially postoperatively, may prove an effective approach for preventing cardiac allograft rejection.

Animals↗
PubMed1995

Development of polyuria in Tsukuba hypertensive mice carrying human renin and angiotensinogen genes.

1. Tsukuba hypertensive mice (THM) carry both human renin and angiotensinogen genes, and develop hypertension. The animal has high levels of renin activity and angiotensin II concentration in the plasma. 2. Urinary excretion in THM was greater than in the control animal, non-transgenic C57BL/6j. THM showed a greater amount of daily water intake. The osmolality of 24 h urine was lower than that of the control animal. 3. When water was deprived for 12 h and then loaded with 0.25 mL/10 g bodyweight, the osmolality of urine at the first 0-3 h period was the same in THM and control, but significantly lower in THM at the following 3-6 h period, indicating that the urine concentrating activity is insufficient in THM compared with the control animal. 4. Urinary excretion of vasopressin was significantly higher in THM. Plasma aldosterone concentration and urinary excretion of aldosterone were also higher in THM. Plasma potassium level was significantly low. 5. The mechanism underlying the pathophysiology of polyuria is not totally explained; however, hypokalaemia, which was probably the result of hyperaldosteronism, may be at least partially involved, since hypokalaemia is considered to be a factor hampering the action of vasopressin for concentration of urine at the site of the collecting duct of the kidney.

Aldosterone↗
PubMed1995

[A preliminary analysis of unrelated marrow transplantations facilitated by the Japan Marrow Donor Program (JMDP)].

Between January 1993 and June 1994, the JMDP facilitated marrow donations from unrelated donors for 171 patients with malignant and non-malignant disorders. The median age of the patients was 21 years. All patients received marrow from phenotypically HLA -A, -B, -DR identical donors. About half of the patients wrer treated with total body irradiation (TBI)-containing regimens and about 80% of the patients received short-courses methotrexate and cyclosporine for graft-versus-host disease (GVHD) prophylaxis. Eight out of 171 patients, (4.7%) had graft failure and 63 out of 144 patients (44%), who survived for more than 30 days posttransplant, developed grade II to IV acute GVHD. The incidence of chronic GVHD was 47% (extensive form; 27%); most of them were progressive/quiscent type. The incidence of moderate to severe acute GVHD was higher than that observed in sibling transplants. On the other hand, the incidence of chronic GVHD was similar to that observed in sibling transplants. Overall survival at 1.5 years posttransplant was about 50% with no significant differences between diseases. The age correlated significantly with the survival in standard risk leukemia but not in high-risk leukemia. Despite the risk of graft failure and acute GVHD, this preliminary analysis demonstrates that transplantation of marrow from unrelated donors can be an effective treatment for certain hematologic disorders.

Acute Disease↗
PubMed1995

[A case of congenital tracheal stenosis with tracheomalacia due to esophageal remnants].

We report a case of congenital tracheal stenosis with tracheomalacia, which shows unique histological findings. A 1056 g male infant was delivered by cesarean section for fetal asphyxia at 28 wk of gestation. Immediately after birth, he had frequent apneic spells and required intubation and ventilation for 70 days. After he was discharged at 240 days of age, he had occasional apneic spells and was resuscitated by his family doctor. When he was admitted to our hospital at 11 months of age, he had a respiratory rate of 32 breaths/min with retractions, and auscultation revealed biphasic wheezes. Chest X-ray and bronchoscope examination showed a stenotic and malacic section of the upper trachea. When he was 1 year and 2 months old, an operation was performed. The diseased portion was resected and end-to-end anastomosis with interrupted absorbable suture was performed. The postoperative course was uneventful and he was discharged from our hospital on the 46th postoperative day. Histologically, the cartilaginous ring was composed of some islets of cartilage. Furthermore, there were some striated muscle cells on the inside of the incomplete cartilaginous ring. To our knowledge, this finding has never been reported in earlier papers. We suppose that some of the visceral mesenchymal tissue which should form the esophagus became sequestered in the tracheal region before the esophageal and tracheal tubes completely separated.

Cartilage Diseases↗
PubMed1995

[Reoperation for recurrent or second primary lung cancer].

From 1975 to July 1994, twenty patients underwent second or third pulmonary resections for 7 recurrent lung cancers and 14 second primary lung cancers. The initial surgical procedures were lobectomy in 18, pneumonectomy in 1 and bilateral segmentectomy in 1. The procedures at the second operation were completion pneumonectomy in 4, ipsilateral wedge resection in 3, contralateral lobectomy in 1, contralateral segmentectomy in 4, contralateral wedge resection in 7 and resection of left main bronchus in 1. At the third operation, wedge resection was done in one 28 months after completion pneumonectomy. There was no operative death following second and third operations. Five-year survival rate following second operation in 20 patients was 32.3%, and it was 28.6% for patients with recurrent lung cancers, and 31.2% for multiple primary lung cancers. In conclusion, an aggressive surgical approach for reappearing lung tumor should be performed. At the reoperation, wedge resection for recurrent lung cancers, completion pneumonectomy for ipsilateral primary lung cancers and segmentectomy for contralateral primary lung cancers should be chosen for the standard surgical procedure.

Adenocarcinoma↗
PubMed1995

[Laparoscopic unroofing of a renal cyst].

Laparoscopic unroofing of a renal cyst was performed in 13 cases of simple cysts of 48 ml. to 678 ml. (mean: 217 ml.) preoperatively measured by ultrasonography from April, 1994 through April, 1995 at our Department of Urology. Under general anesthesia, the renal cyst wall was resected as close as possible to the renal parenchyma by the laparoscopic technique. The postoperative outcome was evaluated in 12 of 13 cases, except for the one case converted to laparotomy because of uncontrollable bleeding from the resected site of the renal parenchyma. Three months after the operation, complete disappearance of the renal cyst was noted by CT scanning in 10 of the 12 cases. In the remaining 2 cases, the renal cyst was still in existence despite the apparent reduction of the cyst volume. In one case in which a somewhat large cyst remained, sclerotherapy using minocycline was carried out. No serious complications during the operation were observed, but in one case with uncontrollable bleeding as mentioned above, the postoperative course was uneventful. These findings indicate that, the laparoscopic unroofing of a renal cyst is a safe and useful procedure for a relatively large renal simple cyst, therefore this approach seems to be acceptable, and before long it will be an ordinary urological operation.

Aged↗
PubMed1995

T cell reconstitution by haploidentical BMT does not restore the diversification of the Ig heavy chain gene in patients with X-linked SCID.

We previously examined the Ig heavy (H) chain gene of pretransplant patients with X-linked SCID (XSCID), having defects in the gene of the IL-2 receptor (R) gamma chain. In the present study, we analyzed two post-transplant XSCID patients, in whom T cell-depleted haploidentical BMT resulted in lymphoid split chimeras, i.e., donor functional T cells coexisting with recipient B cells. Although the recipient B cells produced IgM, no isohemagglutinin or Ag-specific Ab was detected. To investigate the cause of failure to produce Ab in the patients, we sequenced the complementarity determining region 3 (CDR3) and adjacent region of Ig H chain gene, which govern Ab specificity. Among the 64 post-transplant CDR3 junctional sequences, combinatorial and junctional diversity were normal compared with those in age-matched controls. All of the post-transplant joining regions except one clone were equal to germline and the frequency of somatic mutation was significantly lower than that in age-matched controls. The results indicated that T cell reconstitution by BMT does not restore diversification of the Ig gene in the IL-2R gamma chain-deficient B cells, which might be associated with the defect in the Ag-specific Ab production.

Base Sequence↗
PubMed1994

Glucocorticoid independence of acute thymic involution induced by lymphotoxin and estrogen.

Acute thymic involution is known to be induced under conditions of physical stress, bacterial infections, and malignancies. It is speculated that glucocorticoids, tumor necrosis factor (TNF), and other factors may act as mediators for the thymic involution under such conditions. It was herein investigated whether either lymphotoxin (TNF beta) or estrogen could induce thymic involution without the help of glucocorticoids. Interestingly, both lymphotoxin or estrogen alone induced profound thymic involution even in adrenalectomized mice. In contrast to glucocorticoids, which induce lymphocytopenia throughout the organs, lymphotoxin and estrogen did not induce lymphocytopenia in the peripheral organs. More importantly, lymphotoxin and estrogen rather stimulated extrathymic T cells in the liver and other organs. These results suggest that lymphotoxin and estrogen per se might be important regulators of immune systems.

Animals↗
PubMed1994

T cell receptor peptide therapy for autoimmune encephalomyelitis: stronger immunization is necessary for effective vaccination.

Although T cell receptor (TCR) peptide therapy was initially reported to be a very effective method for prevention of the development of experimental autoimmune encephalomyelitis (EAE), it was recently demonstrated that the same peptide immunization led to enhanced and chronic EAE in some cases. In the present study, we examined the effect of the TCR peptide (V beta 8.2-39-59) vaccination on the development of EAE by employing several immunization protocols. We found that TCR peptide vaccination effectively prevented EAE development only when the peptide was injected with Mycobacterium tuberculosis-enriched CFA in the vicinity of the challenge site. Under such conditions, a sufficient number of peptide-reactive T cells were generated. Flow cytometry and immunohistochemical analyses using anti-peptide antibody and anti-V beta 8.2 mAb revealed that despite the presence of V beta 8.2+ cells, very few peptide-positive T cells appeared in the lymphoid organs throughout the course of EAE. These findings imply that antibodies that are generated after immunization with V beta 8P are hardly accessible to their specific epitopes in the native protein. Insufficient generation of both T cells and antibodies against V beta 8.2-positive T cells may be attributable to the outcome of the therapy. To establish effective TCR peptide immunotherapy, these disadvantages should be overcome by using other TCR sequences and/or by employing a more suitable adjuvant.

Adjuvants, Immunologic↗