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T Iwase

Publications and source records attributed to T Iwase.

At least 19 recordsLinked to original sources
PubMed1998

Secretory IgA induces degranulation of IL-3-primed basophils.

We examined whether secretory IgA (sIgA), known to mediate eosinophil stimulation, has an effect on basophil functions. An immobilized preparation of sIgA, but not of monomeric IgA, induced histamine release (approximately 15% of total histamine contents) from human basophils in vitro. sIgA-induced basophil histamine release was totally dependent on pretreatment with IL-3. IL-5 and granulocyte-macrophage CSF also primed basophils for sIgA-mediated release. Exogenous divalent ions, i.e., Ca2+ and Mg2+, were essential for sIgA-mediated basophil degranulation, and the degranulation was completed within 45 min. A newly synthesized lipid mediator, leukotriene C4, was also liberated from IL-3-primed, sIgA-stimulated basophils. Enzyme digestion experiments revealed that the (Fc)2 x secretory component portion of sIgA is important for sIgA-mediated basophil activation, but the functional binding sites of sIgA on basophils were surmised to be different from FcalphaR. These observations reveal the novel finding that sIgA is able to stimulate basophils as well as eosinophils. Since sIgA is the most abundant Ig isotype in the secretions from mucosal tissues, and basophils are active participants in allergic late-phase reactions, sIgA-mediated basophil mediator release is potentially involved in exacerbation of the inflammation associated with allergic disorders.

Basophils↗
PubMed1998

Scintigraphic evaluation of transtrochanteric rotational osteotomy for osteonecrosis of the femoral head. Comparison between scintigraphy, radiography and outcome in 34 patients.

Scintigrams and radiographs of 36 femoral heads in 34 patients before and after Sugioka's transtrochanteric rotational osteotomy for osteonecrosis of the femoral head were investigated prospectively. Patients were followed for more than 3 years after the operation. The patterns of early scintigrams made within 3 months of the operation were classified into four categories. All 4 patients with a large cold area evidenced collapse within 1 year despite good recovery of the weight-bearing surfaces immediately after operation on conventional radiograms. Twenty-two hips with no cold area in the femoral head did not demonstrate collapse. Femoral head collapse after rotational osteotomy can be predicted by early postoperative bone scintigraphy.

Adolescent↗
PubMed1998

An unusual course of progressive multifocal leukoencephalopathy in a patient with idiopathic CD4+ T lymphocytopenia.

A case is reported of idiopathic CD4+T lymphocytopenia with progressive multifocal leukoencephalopathy and cervical lymph node tuberculosis. A 57 year old Japanese man presented with cervical lymphadenopathy and progressive neurological deficits, and six months later he developed akinetic mutism. He had a persistent severely depressed number of circulating CD4+T lymphocytes in the absence of human immunodeficiency virus infection. T1 weighted MRI showed a diffuse decreased signal intensity limited to the white matter without mass effect. A brain biopsy specimen had a morphology similar to that of progressive multifocal leukoencephalopathy. Polyomavirus antigen was detected in the brain lesion, and viral DNA was identified in nucleated blood cells and urine. Unusually this serious medical condition has lasted for more than three years without remission. To our knowledge this is the first patient with CD4+T lymphocytopenia with progressive multifocal leukoencephalopathy, suggesting that similar opportunistic infections should be considered even in previously normal people.

Antigens, Viral↗
PubMed1998

Long-term outcome in triple-vessel coronary artery disease in medically treated Japanese patients.

The long-term outcome in 198 patients with triple-vessel disease (TVD) treated medically was investigated. The patients, who underwent coronary angiography between September 1973 and February 1984, had significant (75% or more) stenotic lesions in all three major coronary arteries. The mean follow-up period was 8.4 years. The 5- and 10-year survival rates were 80.7% and 64.2%, respectively. Cardiac death occurred in 73 patients (36.9%) and nonfatal cardiac events developed in 60 patients (30.9%) during follow-up. When cardiac death and nonfatal myocardial infarction (MI) were defined as cardiac events, the annual attrition rate was 4.7%. There was no difference in survival with regard to the presence or absence of MI, the site of infarction, or the presence of total occlusion. In the AP group, however, the survival rate decreased as the number of totally-occluded arteries increased. In the MI group, the survival rate was not altered by the number of totally-occluded arteries, but was affected by the ejection fraction (EF). The 5-year survival rate was better in patients with good left ventricular function (EF > or = 60%) than in those with impaired left ventricular function (EF < 60%), although the 10-year survival rate was similarly low in both groups. Revascularization such as PTCA or CABG might improve the long-term outcome in patients with TVD.

Angina Pectoris↗
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↗
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↗