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Y Tsuji

Publications and source records attributed to Y Tsuji.

At least 55 records · Page 3Linked to original sources
PubMed2001

Expression of interleukin-18 and its receptor in mouse ovary.

PROBLEM: Interleukin-18 (IL-18) strongly induces interferon-gamma production and is produced not only by types of immune cells but also by types of non-immune cells. Ovulation is thought to be an inflammation-like reaction in which many pro-inflammatory cytokines are involved. We investigated whether IL-18 is involved in the functions of ovary. METHOD OF STUDY: The 4-week-old immature female mice were examined for IL-18 and IL-18 receptor (IL-18R) expression on their ovaries under stimulation with pregnant mare's serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) by immunohistochemical staining, Western blotting and reverse transcript-polymerase chain reaction. The IL-18R was blocked by the injection of anti-IL-18R monoclonal antibody to immature mice during PMSG-hCG stimulation, and the number of ovulated ova was counted. RESULTS: The expression of both proteins and mRNA of IL-18 and IL-18R were very low in immature ovaries before stimulation, but after PMSG injection both IL-18 and IL-18R increased dramatically in theca cells and reached a maximum level at the peri-ovulatory phase then slightly lowered, but still kept a high level during the luteal phase in the corpus luteum. The treatment of IL-18R monoclonal antibody to the mice during ovarian stimulation reduced the number of ovulated ova and inhibited the expansion of cumulus cells surrounding the ovum. CONCLUSION: IL-18 and IL-18R play roles in various kinds of function of ovary.

Animals↗
PubMed2001

Functional and aesthetic reconstruction of full-thickness cheek, oral commissure and vermilion.

PURPOSE: This paper presents surgical techniques for reconstruction of the cheek, oral commissure and vermillion in the repair of full-thickness cheek defects after resection of buccal-mucosal squamous cell carcinoma. PATIENTS AND METHODS: Four reconstructions in one-stage surgery with either a free radial forearm flap or a rectus abdominis musculocutaneous flap for cheek and oral commissure were carried out. There were combined with a new approach for vermillion advancement flaps. Most challenging was the need not only for morphological reconstruction of the orifice, but also for physiological reestablishment of sphincteric and sensory functions in the vermillion. RESULTS: Morphological and physiological reconstruction of the lip with sphincteric and sensory functions was attained. CONCLUSION: This valuable reconstruction technique was demonstrated in large, full thickness defects involving the cheek, oral commissure and vermilion.

Aged↗
PubMed2001

Renal cell carcinoma with extension of tumor thrombus into the vena cava: surgical strategy and prognosis.

PURPOSE: The outcome of patients who underwent radical resection of renal cell carcinoma extending into the vena cava was retrospectively analyzed, and risk factors for long-term survival were investigated. METHODS: From 1983 to 1999, 33 patients who had renal cell carcinoma with inferior vena caval tumor extension underwent 34 surgical procedures. There were 27 men and six women with an average age of 60.1 years. Twenty-two cases (64.7%) were classified as stage III (T1-2 N1 M0 or T3 N0-1 M0), and 12 cases (35.3%) as stage IV (T4 or N2-3 or M1). Coexistent lung metastasis was found in seven cases (20.6%). The tumor thrombi invaded into the inferior vena cava below the hepatic hilum in 19 cases, below the orifice of hepatic veins in 12, and above the diaphragm in 3. Cardiopulmonary bypass graft was applied in 13 cases (38.2%). Inferior vena cava was reconstructed by direct suture (n = 19), polytetrafluoroethylene patch angioplasty (n = 13), or graft replacement (n = 2). RESULTS: Two patients died during the early postoperative period because of retrohepatic caval injury and intraoperative pulmonary embolism. Late death occurred in 16 patients; the causes of death were tumor recurrence in 15 and acute pulmonary embolism as a result of graft thrombosis in 1. Overall 1-, 5-, and 10-year survival rates were 70%, 44%, and 26.4%, respectively. One- and 5-year survival rates were 81.3% and 52.9% for stage III and 50% and 31.2% for stage IV; a statistically significant correlation was found between surgical staging and survival (P =.049). Patients without lymph node metastasis had a significant survival advantage over those with lymph node metastasis (P =.022). There was no significant difference in survival on the basis of the presence or absence of synchronous lung metastasis (P =.291). The degree of local extension of the tumor or the level of tumor thrombus did not tend to influence survival. CONCLUSIONS: Surgical prognosis in patients with renal cell carcinoma extending into the vena cava was determined by the staging of the tumor, especially lymph node status, and not by the level of tumor thrombus or the presence of concurrent lung metastasis. The use of cardiopulmonary bypass graft is recommended for the resection of tumor thrombus extending over the diaphragm.

Adult↗
PubMed2001

Identification and characterization of an antibacterial peptide of the 26-kDa protease of Sarcophaga peregrina with antibacterial activity.

Previously, we purified a serine protease with a molecular mass of 26 kDa that exhibits potent antibacterial activity from a pupal extract of Sarcophaga peregrina (flesh fly). We divided this protease into 12 peptides and examined their antibacterial activity. A peptide corresponding to residues 155 to 174 (peptide 9) was found to exhibit antibacterial activity comparable to that of the 26-kDa protease. When Escherichia coli was treated with peptide 9, the permeability of both the outer and inner membranes increased, and substrates for beta-lactamase and beta-galactosidase entered the cells, but beta-galactosidase did not leak out of the cells under these conditions. It was suggested that residues 6 to 18 of peptide 9 form an amphiphilic alpha-helix under hydrophobic conditions with an N-terminal basic loop and then interact with acidic phospholipids in the bacterial membranes.

Amino Acid Sequence↗
PubMed2001

Deep vein thrombosis caused by congenial interruption of the inferior vena cava--a case report.

Congenital interruption of the inferior vena cava is an uncommon vascular anomaly. In this setting, the appearance of deep vein thrombosis is very rare because associated azygous or portal continuation develops as a collateral system for venous return. The authors present a case of infrahepatic interruption of the inferior vena cava in a 21-year-old man who presented with symptoms of deep vein thrombosis. Clinical features and prognosis of this entity are discussed.

Adolescent↗
PubMed2001

Subcellular localization of insulin receptor substrate family proteins associated with phosphatidylinositol 3-kinase activity and alterations in lipolysis in primary mouse adipocytes from IRS-1 null mice.

To clarify the roles of insulin receptor substrate (IRS) family proteins in phosphatidylinositol (PI) 3-kinase activation and insulin actions in adipocytes, we investigated the intracellular localization of IRS family proteins and PI 3-kinase activation in response to insulin by fractionation of mouse adipocytes from wild-type and IRS-1 null mice. In adipocytes from wild-type mice, tyrosine-phosphorylated IRS-1 and IRS-2, which were found to associate with PI 3-kinase in response to insulin, were detected in the plasma membrane (PM) and low-density microsome (LDM) fractions. By contrast, tyrosine-phosphorylated IRS-3 (pp60), which was found to associate with PI 3-kinase, was predominantly localized in the PM fraction. In adipocytes from IRS-1-null mice, insulin-stimulated PI 3-kinase activity in anti-phosphotyrosine (alphaPY) immunoprecipitates in the LDM fraction was almost exclusively mediated via IRS-2 and was reduced to 25%; however, insulin-stimulated PI 3-kinase activity in the PM fraction was primarily mediated via IRS-3 and was reduced to 60%. To determine the potential functional impact of the distinct subcellular localization of IRSs and associating PI 3-kinase activity on adipocyte-specific metabolic actions, we examined lipolysis in IRS-1 null mice. The level of isoproterenol-induced lipolysis was increased 5.1-fold in adipocytes from IRS-1 null mice as compared with wild-type mice. Moreover, hormone-sensitive lipase (HSL) protein was increased 4.3-fold in adipocytes from IRS-1-null mice compared with wild-type mice, and HSL mRNA expression was also increased. The antilipolytic effect of insulin in IRS-1 null adipocytes, however, was comparable to that in wild-type mice. Thus, discordance between these two insulin actions as well as the transcriptional and translational effect (HSL mRNA and protein regulation) and the PM effect (antilipolysis) of insulin may be explained by distinct roles of both PI 3-kinase activity associated with IRS-1/IRS-2 and PI 3-kinase activity associated with IRS-3 in insulin actions related to their subcellular localization.

Adipocytes↗
PubMed2001

Adult colonic intussusception: a case report.

Intussusception accounts for almost all cases of intestinal obstruction in children. In contrast, intussusception in adults is relatively rare. An 86-year-old Japanese female with rectal bleeding came to our hospital via ambulance. At first, colonoscopy findings revealed the sigmoid colon cancer. Ultrasonography showed a hypoechoic mass with a multiple concentric ring sign. Computed tomography showed a round fluid-filled cystic structure. Colon contrast studies demonstrated stenosis in the rectosigmoid colon. A laparotomy was performed. The sigmoid colon was intussuscepted to the rectosigmoid colon. We employed both rectosigmoid and sigmoid colon resection. The resected specimen showed that the disease was advanced sigmoid colon cancer with ulcer formation due to an ischemic change. Tumor was 4.5 cm x 2.0 cm in size. The disease was histopathologically diagnosed as advanced sigmoid colon cancer, well-differentiated adenocarcinoma. We report here a case of adult intussusception due to the sigmoid colon cancer.

Aged↗
PubMed2001

Laparoscopic ileus operation due to paracolostomy hernia.

We present a case report of a 62-year-old man with adhesive ileus caused by paracolostomy hernia. The patient underwent enterosynechotomy for ileus and colopexy for paracolostomy hernia laparoscopically. This procedure has benefits of prevention of recurrent adhesive ileus and early postoperative recovery of the intestinal tract.

Colostomy↗
PubMed2001

Localized activation of m-calpain in migrating human umbilical vein endothelial cells stimulated by shear stress.

Using a parallel-plate flow-chamber and confocal laser scanning microscopy (CLSM), we studied the mode of cytoskeletal reorganization in migrating HUVECs stimulated by shear stress. Activation of m-calpain associated with a change in the spatial distribution of cytoplasmic ionized Ca2+ concentration ([Ca2+](i)) was studied. Shear stress (10 dyne/cm(2)) caused migration and decrease in the F-actin content of HUVECs. Migrating individual HUVECs showed the lamellipodium formed in the direction of cell migration, in which [Ca2+](i) elevated to 148 +/- 12 nM in a localized fashion. We found the appearance of activated m-calpain in the local area of the migrating HUVECs, which was associated with a decrease in the amounts of pp125FAK and ezrin. The localized rise in [Ca2+](i) might be closely related to morphological change to regulate the direction of cell migration induced by shear stress through localized activation of m-calpain.

Aniline Compounds↗
PubMed2001

[The sensitivity and clinical implications of periodical bladder biopsy following transurethral resection of superficial bladder transitional cell carcinoma].

The role of the periodical bladder biopsy after transurethral resection (TUR-Bt) of superficial bladder cancer (sBT) was evaluated. Sixty-four patients (85 TURs) with sBT who underwent TUR-Bt between 1993 and 1998 were divided into 14 (22 TURs) who had carcinoma in situ (CIS) at the first TUR (group A), and 50 (64 TURs) who had papillary tumors without concomitant CIS (group B). Post-TUR intravesical instillation was performed with bacillus Calmette-Guerin for the majority of group A, and mitomycin C for the majority of group B. The first biopsy was performed at 3 months postoperatively, and the second biopsy was done at 8 to 12 months postoperatively. The mean observation time was 4 years and 6 months. Residual cancer was detected in 7 out of 34 biopsies (20.6%) in group A, and 19 out of 94 (20.2%) in group B. Every residual lesion in group A was CIS with negative cytology. In group B, with exclusion of 11 recurrent papillary tumors, the detection rate was only 8/83 (9.6%). In both groups, even in the cases with no sign of disease in biopsies, the recurrence immediately after the termination of the biopsy protocol was common. The progression of the cancer was more frequent in group A (4 patients), than in group B (2 patients) (p < 0.01, log-rank test), and no case in group B showed local progression. The periodical biopsy may have a certain, but limited advantage over conventional examinations. A less invasive and more sensitive method in awaited.

Biopsy↗
PubMed2001

[Consideration of surgical treatment for recurrence after the resection of hepatic metastases from colorectal cancer].

We considered treatment for recurrence following the resection of hepatic metastases from colorectal cancer. The subjects of this study were 15 of 29 patients who had undergone WHF arterial infusion following resection of hepatic metastases from colorectal cancer, in whom there was a recurrence. Of these 15 cases, 6 involved recurrence in a single organ (residual liver, 4; lung, 1; local area, 1), 7 involved two organs (residual liver and lung, 2; residual liver and local area, 2; residual liver and bone, 1; spleen and intra-abdominal lymph node, 1; intra-abdominal lymph node and peritoneum, 1) and 2 involved three organs (lung, bone and abdominal wall, 1; lung, peritoneum and distal lymph node, 1). Reresection was performed in all cases in which recurrence occurred in a single organ. For those cases in which recurrence occurred in two or more organs, reresection and infusion were performed in the 4 cases of recurrence in the residual liver and reresection was performed in the case of recurrence in the spleen and intra-abdominal lymph node (No. 16), the case of local recurrence and the case involving the abdominal wall. The 5-year survival rate of the 29 cases who underwent initial hepatic resection was 61.9%. Five years following resection, the recurrence rate in the residual liver was 38.3%. The survival rates following treatment for recurrence were 76.9, 51.3 and 25.6% for 1, 3 and 5 years, respectively. Of the 8 deaths which have occurred to date, only one was directly related to an increase in hepatic metastases. Following resection of hepatic metastases from colorectal cancer, WHF provides a high rate of prevention as well as a high survival rate. Furthermore, with regard to recurrence following WHF treatment, if the recurrence is in only one organ, there is the possibility of achieving effective treatment by reresection (WHF = 5-FU 1,000 mg/m2 5 hrs qw).

Colorectal Neoplasms↗
PubMed2001

Intravenous nedaplatin and intraarterial cisplatin with transcatheter arterial embolization for patients with locally advanced uterine cervical cancer.

Nedaplatin is a platinum analog that has less renal toxicity and higher efficacy for uterine cervical cancer than cisplatin. Intraarterial cisplatin has been shown to be more effective than intravenous cisplatin in the treatment of cervical cancer. To improve the prognosis of cervical cancer, we studied combination chemotherapy of intravenous nedaplatin and intraarticular cisplatin with transcatheter arterial embolization (TAE). The criteria for selecting patients for this study were as follows: age 16-75 years, stage Ib2-IV according to the classification of the International Federation of Gynecology and Obstetrics (FIGO), performance status between 0 and 2, a creatinine clearance of >40 ml/min, adequate bone marrow and adequate renal and hepatic function. Thirty-two patients, aged 29-72 years (median: 55) were treated. FIGO stage was Ib2 in seven patients, IIa in seven patients, IIb in four, IIIa in one, IIIb in seven and IVa in six. Twenty-four patients had squamous cell carcinoma, three had adenocarcinoma and five had adenosquamous carcinoma. Written informed consent was obtained from all patients. Nedaplatin (30-70 mg/m2) was administered intravenously on day 1 and cisplatin (70 mg/m2) was administered intraarticularly via both uterine arteries on day 3 using the Seldinger method. TAE was then performed. This course of treatment was repeated every 3 weeks for 2-3 cycles. Response to the therapy was defined by magnetic resonance imaging. Partial response was found in 59% patients (19/32) and complete response in 34% (11/32), with an overall response rate of 94% (30/32). Myelosuppression was manageable. No grade 2 neurotoxicity was observed. The median follow-up was 32 months (6-53 months), with 84% of patients showing an overall survival of 1 year and 77% showing an overall survival of 2 years. These results show that this combination chemotherapy effected a high response rate. However, its influence on long-term survival remains to be determined.

Adenocarcinoma↗
PubMed2000

Structural basis of glutamate recognition by a dimeric metabotropic glutamate receptor.

The metabotropic glutamate receptors (mGluRs) are key receptors in the modulation of excitatory synaptic transmission in the central nervous system. Here we have determined three different crystal structures of the extracellular ligand-binding region of mGluR1--in a complex with glutamate and in two unliganded forms. They all showed disulphide-linked homodimers, whose 'active' and 'resting' conformations are modulated through the dimeric interface by a packed alpha-helical structure. The bi-lobed protomer architectures flexibly change their domain arrangements to form an 'open' or 'closed' conformation. The structures imply that glutamate binding stabilizes both the 'active' dimer and the 'closed' protomer in dynamic equilibrium. Movements of the four domains in the dimer are likely to affect the separation of the transmembrane and intracellular regions, and thereby activate the receptor. This scheme in the initial receptor activation could be applied generally to G-protein-coupled neurotransmitter receptors that possess extracellular ligand-binding sites.

Amino Acid Sequence↗
PubMed2000

Cryptic dimer interface and domain organization of the extracellular region of metabotropic glutamate receptor subtype 1.

Previously, we produced the whole extracellular region of metabotropic glutamate receptor subtype 1 (mGluR1) in a soluble form. The soluble receptor retained a ligand affinity comparable with that of the full-length membrane-bound receptor and formed a disulfide-linked dimer. Here, we have identified a cysteine residue responsible for the intermolecular disulfide bond and determined domain organization of the extracellular region of mGluR1. A mutant, C140A, was a monomer under nonreduced conditions by SDS-polyacrylamide gel electrophoresis; however, C140A was eluted at the position similar to that of mGluR113, the wild type soluble receptor, by size exclusion column chromatography. Furthermore, C140A bound a ligand, [(3)H]quisqualate, with an affinity similar to that obtained by mGluR113. Oocytes injected with RNA for full-length mGluR1 containing C140A mutation showed responses to ligands at magnitudes similar to those with wild type full-length RNA. Thus, elimination of the disulfide linkage did not perturb the dimer formation and ligand signaling, suggesting that cryptic dimer interface(s) possibly exist in mGluR1. Limited proteolysis of the whole extracellular fragment (residue 33-592) revealed two trypsin-sensitive sites, after the residues Arg(139) and Arg(521). A 15-kDa NH(2)-terminal proteolytic fragment (residue 33-139) was associated with the downstream part after the digestion. Arg(521) was located before a cysteine-rich stretch preceding the transmembrane region. A new shorter soluble receptor (residue 33-522) lacking the cysteine-rich region was designed based on the protease-sensitive boundary. The purified receptor protein gave a K(d) value of 58.1 +/- 0.84 nm, which is compatible to a reported value of the full-length receptor. The B(max) value was 7.06 +/- 0. 82 nmol/mg of protein. These results indicated that the ligand-binding specificity of mGluR1 is confined to the NH(2)-terminal 490-amino acid region of the mature protein.

Alanine↗
PubMed2000

Palladium-catalyzed cyanation of propargylic carbonates with trimethylsilyl cyanide

[reaction: see text]An equimolar mixture of propargylic carbonate (1) and trimethylsilyl cyanide (2) in THF under reflux affords cyanoallene (3) in the presence of a catalytic amount (5 mol %) of Pd(PPh3)4. In the reaction, the trimethylsilyl moiety of 2 effectively traps the leaving group of 1. The use of 2 in excess (6 equiv) provides dicyanated products (7 or 8) in high yields.

Journal Article↗
PubMed2000

Human umbilical vein endothelial cells (HUVECs) show Ca(2+) mobilization as well as Ca(2+) influx upon hypoxia.

Bleb formation is an early event of cellular damage observed in a variety of cell types upon hypoxia. Although we previously found that the [Ca(2+)](i) rise before bleb formation only at the same loci of HUVECs upon hypoxia (localized [Ca(2+)](i) rise), the mode of the [Ca(2+)](i) rise remains ill-defined. In order to clarify the mechanisms causing the localized [Ca(2+)](i) rise in hypoxia challenged HUVECs, we studied the effects of several Ca(2+) channel blockers or a Ca(2+) chelator, EGTA, which reduces extracellular Ca(2+) concentration on the hypoxia-induced localized [Ca(2+)](i) rise and bleb formation by employing a confocal laser scanning microscopy (CLSM). After the initiation of hypoxia, [Ca(2+)](i) rose gradually in a localized fashion up to 15 min, which was associated with bleb formation at the same loci. The maximal [Ca(2+)](i) rise was 435 +/- 84 nM at the loci of bleb formation. Ca(2+) channel blockers including Ni(2+) (non-specific, 1 mM), nifedipine (L type, 10 microM), nicardipine (L + T type, 10 microM), and cilnidipine (L + N type, 10 microM) did not inhibit either the localized [Ca(2+)](i) rise or bleb formation. Although both the localized [Ca(2+)](i) rise and bleb formation were inhibited by lowering extracellular Ca(2+) concentration below 100 nM, a diffuse [Ca(2+)](i) rise through the cytoplasm remained without bleb formation, which was inhibited by a phospholipase C (PLC) inhibitor, U73122. In conclusion, hypoxia causes both the Ca(2+) mobilization and the Ca(2+) influx in HUVECs and the Ca(2+) influx through unknown Ca(2+) channels is responsible for the localized [Ca(2+)](i) rise integral to bleb formation.

Calcium↗
PubMed2000

Antiarrhythmic efficacy of dipyridamole in treatment of reperfusion arrhythmias : evidence for cAMP-mediated triggered activity as a mechanism responsible for reperfusion arrhythmias.

BACKGROUND: Intracellular calcium overload is believed to play an important role in development of reperfusion arrhythmias. Dipyridamole, an inhibitor of cellular uptake of adenosine, may prevent or terminate reperfusion arrhythmias by reducing intracellular calcium overload. METHODS AND RESULTS: First, we tested for a preventive effect of dipyridamole. Sixty-one patients who underwent primary PTCA for treatment of acute anterior wall myocardial infarction were enrolled in this prospective study. Patients were divided into dipyridamole (DP) and nondipyridamole (non-DP) groups. The 2 groups had similar baseline characteristics. In the DP group, dipyridamole 0.5 mg/kg was infused intravenously for 3 minutes immediately before reperfusion during primary PTCA. Arrhythmias after reperfusion were analyzed from continuous ECG recordings. None of the patients in the DP group (n=23) had accelerated idioventricular rhythms (AIVR) or ventricular tachycardia (VT). In contrast, 7 (18.4%) had AIVR and 3 (7.9%) had VT in the non-DP group (n=38; P<0.01). Second, we tested for a termination effect of dipyridamole. Dipyridamole 0.5 mg/kg was infused intravenously while continuous ECG recordings were obtained in 9 patients who had either sustained AIVR (n=7) or sustained VT (n=2) after reperfusion of occluded coronary artery. Arrhythmias were terminated in all patients. CONCLUSIONS: These results indicate that administration of dipyridamole can prevent and terminate reperfusion arrhythmias such as AIVR and VT. cAMP-mediated triggered activity may, at least in part, be responsible for reperfusion-induced AIVR and VT.

Adenosine↗