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T Iwase

Publications and source records attributed to T Iwase.

At least 73 records · Page 4Linked to original sources
PubMed1998

Gene expression of fucosyl- and sialyl-transferases which synthesize sialyl Lewisx, the carbohydrate ligands for E-selectin, in human breast cancer.

The adhesion of circulating cancer cells to vascular endothelium is an important step in the hematogenous metastasis of cancer. Until recently, it has been believed that carbohydrate antigens are expressed on cancer cells, and E-selectin is expressed on endothelial cells to effect this adhesion. We investigated the gene expression of fucosyl-transferase (Fuc-T) and sialyltransferase (ST), which are involved in the synthesis of sialyl Lewisx (s-Lex) in breast cancer by using Northern blot analysis. The concentration of s-Lex in the cancerous portion was increased, compared to that in the adjacent non-cancerous portion. A correlation was found between the concentration of s-Lex and the amount of Fuc-T VI message in 9 cases of breast cancer tissue. Expression of the Fuc-T III message was found in only one case who expressed s-Lea. No expression of the Fuc-T V or VII message was observed. There was no relationship between the concentration of s-Lex and the amount of ST3N and ST4 transcripts. Similar findings were obtained from an analysis using cell lines derived from human breast cancer. When Fuc-T VI gene was transfected to MCF-7 cells, the expression of s-Lex was markedly induced on MCF-7 cells, and the attachment of cancer cells to endothelial cells was enhanced. These findings suggest that Fuc-T VI is chiefly involved in the synthesis of s-Lex on breast cancer cells.

Adult↗
PubMed1998

Synovial fluid cartilage metabolism marker concentrations in osteonecrosis of the femoral head compared with osteoarthrosis of the hip.

OBJECTIVE: Biochemical aspects of the etiology of articular cartilage degeneration in osteonecrosis of the femoral head have not been investigated extensively. We analyzed biochemical conditions in the hip joint cavity, regarding articular cartilage turnover in osteonecrosis of the femoral head (ONFH). METHODS: Cartilage metabolism markers in synovial fluid were measured. Synovial fluid (SF) samples were collected from 19 ONFH cases and 17 control hips with osteoarthrosis (OA). Concentrations of carboxy-terminal type II procollagen peptide (pCOL-II-C), matrix metalloproteinase-3 (MMP-3), and tissue inhibitor of metalloproteinase-1 (TIMP-1) were measured. In addition, concentrations of unsaturated disaccharides of hyaluronic acid (delta di-HA), chondroitin 4-sulfate (delta di-4S), and chondroitin 6-sulfate (delta di-6S) in SF were measured by high performance liquid chromatography. RESULTS: The mean SF concentration of pCOL-II-C was higher on ONFH than in OA. The mean SF MMP-3 level was higher in ONFH than in OA, while the mean SF TIMP-1 level was the same in the 2 groups. The SF concentration of delta di-HA and the delta di-6S/delta di-4S ratio were higher in ONFH than in OA. CONCLUSION: Higher concentrations of cartilage metabolism markers in ONFH compared with OA SF suggest elevated cartilage turnover in the former disease.

Adolescent↗
PubMed1998

[Proposals for revisions of UICC TNM system (1997)--breast cancer].

The TNM system for classification and staging approved by Union Internationale contro le Cancer (UICC)/TNM Committee is designed primarily for patient care and, in this context, is equally applicable to patients in clinical research, community hospitals, and developing countries. It is clearly evident to all who have been involved that international agreement on the classification of cancer at all anatomical sites is exhilarating, since data from around the world can finally be compared with validity. The UICC believes that the TNM system can fulfil the following five objectives: (1) aid in the planning of treatment; (2) give an indication of prognosis; (3) assist in evaluation of the results of treatment; (4) facilitate the exchange of information between centres; and (5) contribute to the continuing investigation of human cancer. The important questions for planning of treatment (1), however, can not be answered by the information of the clinical TNM stage as the concept in the Japanese Joint Committee. The knowledge of the TNM stage does not yield information of prognostic importance (2). More accurate indices of prognosis can be calculated from multivariate analysis to examine many clinicopathological variables, and biological markers along with patient age and nodal status. The analysis makes the difficulties for the results of treatment due to the large number of combinations with T and N subgroups (3) (4). According to the fifth objective (5) of TNM classification, we would like to propose a more simple and pragmatic classification by classifying patients into those requiring surgical approach and adjuvant therapy.

Breast Neoplasms↗
PubMed1998

Failed cementless total hip arthroplasty for osteoarthrosis due to hip dysplasia. A minimum five-year follow-up study.

We performed cementless total hip arthroplasty on patients with secondary osteoarthrosis due to hip dysplasia. We conducted prospective radiographic and clinical studies on 75 hips with a minimum five-year follow-up. Aseptic loosening of the Dual geometry Microstructured cup used on the acetabular component was recognized in 2 of 75 hips within five years postoperatively, but neither case required revision. As for the femoral component, within five years of operation, in 9 of 28 (32%) and 11 of 31 (35%) patients, aseptic loosening was recognized in the Omnifit Normalized Smooth surfaced stem (FIT-N) and the Omniflex Normalized Smooth surfaced stem (FLEX-N), respectively, neither of which have a porous coating on their proximal end. Revisions of the stems have been conducted on three FIT-N and two FLEX-N stems. Aseptic loosening was recognized in 2 of 16 Omnifit Microstructured stems (FIT-M) with porous coating, but revisions have not yet been required in these cases. We conclude that stems without a porous surface coating should not be used for cementless total hip arthroplasty.

Adult↗
PubMed1998

[Relationship between evolution of ischemic heart disease and changes in lipid profile].

The relationship between the evolution of ischemic heart disease and changes in lipid profile was investigated in 115 of 11,875 patients underwent coronary angiography (CAG). The 115 patients had no significant stenosis on initial CAG and underwent repeat CAG for several reasons. Changes in lipid profile and other coronary risk factors were compared in 30 patients who developed ischemic cardiac events (Group E) and 85 patients who did not (Group NE). Ischemic cardiac events were defined as ischemic chest symptoms with ST-T changes or appearance of significant angiographic stenosis. At initial CAG, smoking was significantly more common in Group E (23.3% vs 4.7%, p < 0.01) and high-density lipoprotein cholesterol was significantly lower in Group E (42 +/- 11 vs 48 +/- 15 mg/dl, p < 0.05). At repeat CAG, smoking continued to be significantly more common in Group E (26.7% vs 10.6%, p < 0.05), and serum cholesterol (219 +/- 36 vs 193 +/- 34 mg/dl, p < 0.01) and low-density lipoprotein cholesterol (141 +/- 33 vs 115 +/- 29 mg/dl, p < 0.01) were also significantly higher in Group E. Multivariate analysis revealed only the increase of serum cholesterol at repeat CAG was a significant factor in the evolution of coronary artery disease (p = 0.026). Two patients from Group E died of cardiac causes within 1 year after repeat CAG but no patients in Group NE died (6.7% vs 0%, p < 0.05). Increased serum cholesterol level is related to the evolution of ischemic heart disease and cardiac death.

Cholesterol↗
PubMed1997

Inhibition of sarcolemmal Na+,K+-ATPase activity reduces the infarct size-limiting effect of preconditioning in rabbit hearts.

BACKGROUND: The inhibition of sarcolemmal Na+,K+-ATPase activity is closely related to ischemic myocardial cell injury. However, the involvement of this enzyme in preconditioning has not been determined. METHODS AND RESULTS: We assessed the effect of ischemia on sarcolemmal Na+,K+-ATPase activity. Control and preconditioned rabbits were subjected to 0, 10, 20, 30, and 60 minutes of coronary occlusion. Ten to 60 minutes of ischemia reduced Na+,K+-ATPase activity, whereas preconditioning preserved the activity of this enzyme only during the first 20 minutes of ischemia. To determine whether the preservation of Na+,K+-ATPase activity in the early phase of ischemia contributed to limiting the infarct size, additional rabbits underwent 30 minutes of occlusion followed by 3 hours of reperfusion with or without pretreatment with digoxin, an inhibitor of Na+,K+-ATPase. Infarct size in animals pretreated with digoxin in the absence of preconditioning did not differ from that in controls. It was markedly reduced by preconditioning, whereas digoxin reduced the infarct size-limiting effect. Moreover, preconditioning increased sarcolemmal Na+-Ca2+ exchange activity in rabbits subjected to 20 minutes of ischemia, whereas digoxin diminished this increase. CONCLUSIONS: Preconditioning preserves the ischemia-induced reduction in sarcolemmal Na+,K+-ATPase activity in the early phase of ischemia in rabbit hearts. Inhibition of Na+,K+-ATPase activity reduces the infarct size-limiting effect of preconditioning with a loss of increased Na+-Ca2+ exchange activity, implying that this preservation is responsible for the cardioprotective effect of preconditioning.

Animals↗
PubMed1997

Macrophage activation and migration in interface tissue around loosening total hip arthroplasty components.

The bone-cement interface tissue of failed total hip arthroplasty (THA) has inflammatory characteristics, such as the presence of prostaglandin E2 and interleukin 1 (IL-1). We considered that the bone-cement interface tissue could be the site of granulomatous inflammation caused by a foreign-body reaction. It has been demonstrated that inflammatory cytokines and chemokines have an important role in granulomatous inflammation. Bone-cement interface tissue was obtained at revision from nine patients with failed cemented THA, and the role of macrophages was assessed by immunohistochemistry, electron microscopy, and molecular biological techniques. We used the reverse-transcriptional polymerase chain reaction to examine the expression of mRNA for IL-1 alpha, IL-1 beta, tumor necrosis factor alpha (TNF alpha), macrophage inflammatory protein (MIP)-1 alpha, MIP-1 beta, IL-8, and monocyte chemoattractant protein. Polyethylene debris surrounded by macrophages and phagocytosis of debris by macrophages was frequently observed in the interface tissue. Macrophage activation and the production of inflammatory cytokines such as IL-1 and TNF alpha might induce the development of interface tissue. Expression of chemokine mRNAs was also commonly seen, suggesting that this led to recruitment of macrophages into the bone-cement interface tissue. Debris released from implants appears to cause activation of macrophages and the production of inflammatory cytokines and chemokines that induce cellular recruitment into interface tissue. This mechanism might form a vicious cycle that aggravates THA loosening.

Aged↗
PubMed1997

Fate of collateral vessels after successful coronary angioplasty in patients with effort angina.

OBJECTIVES: The purpose of the present study was to evaluate whether severe restenosis after percutaneous transluminal coronary angioplasty (PTCA) promotes collateral development and whether successful dilation regresses collateral vessels. BACKGROUND: It is well known that in the presence of severe coronary stenosis, native collateral arterioles mature to small coronary arteries with several layers of smooth muscle cells. However, it remains unclear whether well developed collateral vessels regress after removal of coronary stenosis. METHODS: The study group comprised 41 patients who underwent elective PTCA for effort angina due to single-vessel disease, followed by repeat PTCA to treat restenosis. We classified the patients into three groups depending on the change in baseline Thrombolysis in Myocardial Infarction (TIMI) flow grade of the ischemia-related artery at initial and repeat PTCA, and we compared the extent of ST segment elevation at 1 min of the first balloon inflation between the two procedures. The average interval from initial to repeat PTCA was 125 days. RESULTS: The three patient groups comprised group A, 12 patients with decreased flow grade because of severe coronary restenosis; group B, 12 patients with increased flow grade who had severe initial stenosis and relatively mild restenosis; and group C, 17 patients with unchanged flow grade. In the presence of comparable rate-pressure products at initial and repeat PTCA, patients in group A had significantly greater ST segment elevation (p < 0.01) at initial than at repeat PTCA (mean +/- SD 0.42 +/- 0.31 vs. 0.13 +/- 0.22 mV). In group B, ST segment elevation was significantly less at initial than at repeat PTCA (0.13 +/- 0.25 vs. 0.19 +/- 0.17 mV, p < 0.05), and in group C, it was comparable at the two procedures (0.37 +/- 0.32 vs. 0.35 +/- 0.33 mV, p = 0.50). CONCLUSIONS: These findings indicate that severe restenosis after PTCA promotes collateral development and that successful dilaton regresses collateral vessels during a relatively short period of time.

Aged↗
PubMed1997

K(ATP) channels contribute to the cardioprotection of preconditioning independent of anaesthetics in rabbit hearts.

The contribution of ATP sensitive potassium (K(ATP)) channels to the infarct-size limiting effect of preconditioning is considered to be anaesthetic-dependent in the rabbit heart. It has previously been reported that ischaemic preconditioning prevents ischaemia-induced reductions in activities of sarcolemmal adenylate cyclase (AC) and Na+, K(+)-ATPase. Anaesthetic dependency of the role of K(ATP) channels in the preservation of these enzyme activities, induced by ischaemic preconditioning, as well as that induced by activation of A1-adenosine receptors, was examined in rabbits anaesthetized with either pentobarbital or ketamine-xylazine and subjected to 20 min of regional ischaemia. Adenylate cyclase and Na+, K(+)-ATPase activities were lower in the ischaemic than in the non-ischaemic region of the hearts in control rabbits, but not in animals subjected to ischaemic preconditioning, or those pretreated with the A1-adenosine receptor agonist R(-)-N6-(2-phenylisopropyl) adenosine. The protective effects of both ischaemic preconditioning and A1-adenosine receptor activation were prevented by 6 mg/kg, but not 3 mg/kg, of the K(ATP) channel blocker, glibenclamide, in rabbits anaesthetized with pentobarbital, while these effects were prevented by 3 mg/kg of the blocker in rabbits anaesthetized with ketamine-xylazine. Moreover, K(ATP) channel opener, cromakalim, prevented the ischaemia-induced decreases in enzymatic activities in rabbits subjected to either type of anaesthesia. Thus, although the antagonistic effect of glibenclamide is blunted under pentobarbital, compared to ketamine-xylazine anaesthesia, K(ATP) channels contribute to preservative actions independent of the type of anaesthesia in the rabbit heart.

Adenosine Triphosphate↗
PubMed1997

Transtrochanteric rotational osteotomy for osteonecrosis of the femoral head. 43 patients followed for at least 3 years.

We reviewed 48 hips in 43 patients 3-7.1 years (average 4.6 years) after Sugioka transtrochanteric rotational osteotomy for osteonecrosis of the femoral head. The average age at operation was 41 years. Thirty-four patients were men and 9 women. Overall results at the final follow-up were satisfactory in 30 hips (62%). Kaplan-Meier's survivorship was 62% at 3 years and 60% at 5 years postoperatively. Six hips for which the ratio of the intact area of the articular surface on the preoperative lateral radiograph was less than 30% showed further collapse. Five hips were converted to bipolar hemiarthroplasties or total hip arthroplasties. Complications, such as varus deformity, subtrochanteric fracture, and ectopic bone formation, occurred in eight hips. Five of them were operated on in the first 2 years of this series. Three of these five operations had unsatisfactory results. We conclude that satisfactory results can be achieved using this osteotomy by maintaining exact surgical technique and by limiting the surgical indications to hips with an intact area of more than one-third of the entire articular surface on the lateral radiograph of the femoral head.

Adolescent↗
PubMed1997

Vascularized pedicle bone-grafting for nontraumatic avascular necrosis of the femoral head. A 5- to 11-year follow-up.

We investigated the results of 31 hips in 26 patients with nontraumatic (n = 20) and steroid-induced (n = 6) avascular necrosis of the femoral head (ANFH) treated with vascularized iliac pedicle bone graft (PBG). The average age at operation was 38.3 years. Three were women and 23 men. The average follow-up was 8.0 years. The Harris hip score prior to operation and at latest follow-up improved from 62 to 83; one hip collapsed and was revised with a bipolar endoprosthesis. At the final follow-up, 19 hips (63%) were clinically rated as good to excellent, 4 fair, and 7 poor. At the final follow-up, 15 of 27 hips (56%) of stage II before operation showed progressive collapse after bone grafting. In steroid-induced ANFH, in three women, 2 of 4 hips showed poor results. These results are only slightly better than those of core decompression and no better than those obtained after decompression and simple nonvascularized grafts to provide support for the subchondral bone. We concluded that vascularized PBG is sometimes indicated for ANFH in an early stage before collapse of the femoral head.

Adult↗
PubMed1997

Clinical application of transluminal endovascular graft placement for aortic aneurysms.

BACKGROUND: In recent years, transluminal endovascular graft placement techniques have been developed for the treatment of aortic aneurysms. We report our initial clinical experience with endovascular graft placement using a graft developed in our laboratory. METHODS: The procedure was performed in 20 patients with a diagnosed aortic aneurysm. The graft is constructed from a Dacron cylinder, and the surface of the graft is supported with multiple rings of extraflexible wire. After the compactly folded graft is delivered through the sheath to the predetermined target point, the graft is deployed and then pressed against the vessel by balloon inflation. Straight graft insertion was attempted in 10 patients, bifurcated graft insertion in 8, and branched graft insertion in 2. RESULTS: Graft placement was successful in 19 of the patients and unsuccessful in 1. There were no cases of graft migration, aneurysm rupture, or graft destruction during a mean follow-up period of 9 months. CONCLUSIONS: Initial clinical results demonstrated the efficacy and safety of endovascular graft placement using this graft.

Adolescent↗
PubMed1997

Magnetic resonance galactography for a patient with nipple discharge.

A new method of galactography using magnetic resonance imaging for a patient with nipple discharge is developed. The method is as follows; coronal T1-weight images are obtained after an injection of contrast medium of 1 mmol/L Gd-DTPA directly into the discharge duct, before and after rapid intravenous infusion of Gd-DTPA. A case of a 29-year-old woman with ductal carcinoma in situ with minimal invasion is reported, in which all portions of the entire discharge duct system is clearly shown as viewed from the surface and the surrounding area is enhanced with Gd-DTPA. The enhanced area is coincidental with the extent of the disease. This magnetic resonance galactography for patients with nipple discharge may be used to supplement conventional mammography and/or galactography especially for the evaluation of the extent of disease, although it is somewhat inferior to mammographic galactography in terms of differential diagnosis of ductal disease.

Adult↗
PubMed1997

Rapidly destructive arthropathy of the hip in siblings.

A case of rapidly destructive arthropathy of the hip in male siblings aged 74 and 76 years is reported. Hip joints of the brothers were destroyed 12 and 4 months after the onset of symptoms, respectively. Results of clinical and laboratory examinations did not show any features of neuropathic, inflammatory, or septic arthropathy. Pathologically in both patients, osteoarthrotic changes with small foci of bone necrosis and nonspecific inflammation and moderate amount of hemosiderosis in the synovium were observed.

Aged↗
PubMed1997

Demonstration of ras and p53 gene mutations in carcinomas in the forestomach and intestine and soft tissue sarcomas induced by N-methyl-N-nitrosourea in the rat.

The presence of ras family and p53 gene mutations in rat forestomach, intestine and liver tumors and soft tissue sarcomas induced by N-methyl-N-nitrosourea (MNU) was examined using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) followed by direct sequencing analysis. In the forestomach squamous cell carcinomas (SCC), Ha-ras and p53 mutations were detected in 2 (40%) and 4 (80%) of 5 cases, respectively. The figures for Ki-ras and p53 gene mutations in adenocarcinomas of the large and small intestines were 3 (18.8%) and 5 (31.3%) of 16 cases. Soft tissue sarcomas in different sites were found to have mutations of Ki-ras in 7 (23.3%) and of p53 in 9 (30%) of 30 cases. One forestomach SCC and 2 soft tissue sarcomas had double p53 mutations in different exons. Single cases of forestomach SCC and intestinal adenocarcinoma had mutations in both Ki-ras and p53 genes. No mutations were found in counterpart benign tumors or hepatocellular adenomas. The p53 mutation spectrum revealed preferential clustering within exon 8 for the forestomach SCCs, and exons 5 and 8 for the intestinal adenocarcinomas, whereas the distribution was evenly spread through exons 5 to 8 in soft tissue sarcomas. All the detected ras or p53 mutations were G:C to A:T transitions. These results indicate firstly that specific Ki-ras, Ha-ras and p53 gene mutations in MNU-induced lesions are related to particular alkylation sites (G:C to A:T transitions) and secondly, although not essential, Ki-ras, Ha-ras or p53 gene mutations may be involved in the progression stage of forestomach, intestine and soft tissue neoplasms induced by MNU.

Adenocarcinoma↗
PubMed1997

Effect of ethylene thiourea on cultured rat embryos in the presence of hepatic microsomal fraction.

To investigate whether teratogenicity of ethylene thiourea (ETU) is due to ETU per se or to its metabolites, rat embryos cultured in vitro were exposed to 10 and 30 micrograms/ml of ETU in the presence or absence of rat liver microsomal fraction (S9mix). In the absence of S9mix, the incidence of morphological abnormalities increased dose-dependently. In the presence of S9mix, abnormal morphogenesis was almost absent in all embryos. These findings suggest that teratogenicity of ETU is due to ETU per se.

Abnormalities, Drug-Induced↗