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排序方式: 共有6570条查询结果,搜索用时 15 毫秒
71.
TNF-related apoptosis-inducing ligand (TRAIL) frequently induces apoptosis in Philadelphia chromosome-positive leukemia cells 总被引:5,自引:1,他引:5
Uno K Inukai T Kayagaki N Goi K Sato H Nemoto A Takahashi K Kagami K Yamaguchi N Yagita H Okumura K Koyama-Okazaki T Suzuki T Sugita K Nakazawa S 《Blood》2003,101(9):3658-3667
Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and Fas ligand (FasL) have been implicated in antitumor immunity and therapy. In the present study, we investigated the sensitivity of Philadelphia chromosome (Ph1)-positive leukemia cell lines to TRAIL- or FasL-induced cell death to explore the possible contribution of these molecules to immunotherapy against Ph1-positive leukemias. TRAIL, but not FasL, effectively induced apoptotic cell death in most of 5 chronic myelogenous leukemia-derived and 7 acute leukemia-derived Ph1-positive cell lines. The sensitivity to TRAIL was correlated with cell-surface expression of death-inducing receptors DR4 and/or DR5. The TRAIL-induced cell death was caspase-dependent and enhanced by nuclear factor kappa B inhibitors. Moreover, primary leukemia cells from Ph1-positive acute lymphoblastic leukemia patients were also sensitive to TRAIL, but not to FasL, depending on DR4/DR5 expression. Fas-associated death domain protein (FADD) and caspase-8, components of death-inducing signaling complex (DISC), as well as FLIP (FLICE [Fas-associating protein with death domain-like interleukin-1-converting enzyme]/caspase-8 inhibitory protein), a negative regulator of caspase-8, were expressed ubiquitously in Ph1-positive leukemia cell lines irrespective of their differential sensitivities to TRAIL and FasL. Notably, TRAIL could induce cell death in the Ph1-positive leukemia cell lines that were refractory to a BCR-ABL-specific tyrosine kinase inhibitor imatinib mesylate (STI571; Novartis Pharma, Basel, Switzerland). These results suggested the potential utility of recombinant TRAIL as a novel therapeutic agent and the possible contribution of endogenously expressed TRAIL to immunotherapy against Ph1-positive leukemias. 相似文献
72.
Inoue N Ohkusa T Nao T Lee JK Matsumoto T Hisamatsu Y Satoh T Yano M Yasui K Kodama I Matsuzaki M 《Journal of the American College of Cardiology》2004,44(4):914-922
OBJECTIVES: The aim of this study was to investigate the effects of rapid electrical stimulation (RES) of contraction on the expression of connexin (Cx)43 gap junction in neonatal rat cultured ventricular myocytes and the consequent changes of conduction properties. BACKGROUND: The expression and distribution of gap junctions in cardiac muscle can be changed readily under a variety of pathological conditions because of dynamic turnover of Cxs. The effects of RES of contraction on gap junction remodeling are not well understood. METHODS: Neonatal rat ventricular myocytes cultured for five days were subjected to RES (field stimulation) at 3.0 Hz for up to 120 min. RESULTS: Rapid electrical stimulation resulted in a significant upregulation of Cx43 (by approximately 1.5-fold in protein and by approximately 1.9-fold in messenger ribonucleic acid at 60 min). Immunoreactive signal of Cx43 was also increased. Angiotensin II (AngII) content was increased significantly by RES >15 min. Phosphorylated forms of extracellular signal-regulated protein kinase (ERK), c-Jun NH(2)-terminal kinases, and p38 mitogen-activated protein kinases (MAPKs) were all increased dramatically by RES with peaks at 5 - 60 min. Propagation of excitation was visualized by extracellular potential mapping by using a multiple electrode array system. Conduction velocity was increased significantly by RES for 60 to 90 min (25% - 27% increase). Treatment of myocytes with losartan (100 nmol/l) prevented most of these effects of RES; RES-induced upregulation of Cx43 was also prevented by specific inhibitors for ERK and p38 MAPKs. CONCLUSIONS: A short-term RES causes upregulation of Cx43 in cardiomyocytes and a concomitant increase of conduction velocity, mainly through an autocrine action of AngII to activate ERK and p38 MAPKs. 相似文献
73.
Tanaka K Sakai T Nakamura Y Umeda N Lee DJ Nakata Y Hayashi Y Akutsu T Okura T Yamabuki K 《Aging clinical and experimental research》2004,16(1):53-59
BACKGROUND AND AIMS: The purpose of this study was to compare the effects of exercise habituation (3-32 years, mean 13.2 years) on physical vitality among five different groups. METHODS: One hundred and two independent, community-dwelling elderly Japanese men, aged 64.6 +/- 6.6 years, were recruited as subjects. The vital age test battery consisted of various coronary heart disease risk factors and physical fitness elements. RESULTS: The results of analysis of variance revealed that vital age as an index of physical vitality was youngest in joggers (47.9 yr, N=18), intermediate in trekkers (55.8 yr, N=20) and walkers (59.1 yr, N=18), and oldest (69.6 yr, N=20) in patients with ischemic heart disease (IHD). The difference between chronological age and vital age was approximately 15 years (p<0.05) in joggers, and 8 years (p<0.05) in trekkers and walkers. The vital age of sedentary persons (N=26) was only 1.9 years (NS) younger than their chronological age, which was similar to the difference (vital age of 64.1 +/- 8.5 yr vs chronological age of 65.7 +/- 5.4 yr) previously observed in similarly aged exercising IHD patients. CONCLUSIONS: These results indicate that exercise habituation significantly affects the overall health status of most individuals, irrespective of mode of exercise. Among the three modes of exercise, jogging may be most beneficial. Furthermore, regularly exercising coronary patients may have physical vitality similar to that of sedentary men. 相似文献
74.
Suzuki HI Hangaishi A Hosoya N Watanabe T Kanda Y Motokura T Chiba S Kurokawa M 《International journal of hematology》2008,87(5):538-541
Neurological complications during the treatment of hematological malignancies have a wide range of causes. Treatment-related leukoencephalopathy has been recognized as a major complication of combined chemotherapy and radiotherapy for central nervous system (CNS) lymphoma, and can complicate the diagnosis of CNS infection. Herein, we present a patient with diffuse large B-cell lymphoma who developed herpes simplex encephalitis (HSE) and subsequent cytomegalovirus encephalitis after chemoradiotherapy for CNS relapse. Although cerebrospinal fluid examination (CSF) showed no significant pleocytosis, brain magnetic resonance imaging and polymerase chain reaction analysis of the CSF were useful in the diagnosis. With a review of the literature on the association between HSE and radiotherapy for CNS malignancies, our case suggests that an awareness of viral encephalitis is important in the differential diagnosis of acute neurologic disturbance during chemoradiotherapy for CNS lymphoma. 相似文献
75.
Kaneki T Kawashima A Akamatsu T Tanaka N Kubo K Koizumi T Sekiguchi M Hosaka N Honda T Koike S Adachi W 《Journal of gastroenterology》1999,34(2):253-259
We report a rare case of immunoblastic lymphadenopathy (IBL)-like T-cell lymphoma complicated by multiple gastrointestinal
involvement, which appeared to be ameliorated by chemotherapy but resulted in perforative peritonitis. A 66-year-old Japanese
woman who had generalized lymphadenopathy and eruptions was admitted to our hospital because of bloody stool. Colonoscopic
examination revealed hemorrhagic ulcers in the terminal ileum and a saucer-like ulcer in the cecum. Gastrointestinal endoscopy
revealed several ulcerative or elevated lesions in stomach and duodenum. Biopsy specimens of these lesions and of a lymph
node showed characteristic histological features of IBL-like T-cell lymphoma. The initial treatment with prednisolone (PSL)
and cyclophosphamide (CPA) was effective. Six months after the treatment, however, she developed bloody stool again caused
by multiple ulcerative lesions in the large intestine. The recurrence of the disease was determined histologically, and four
courses of CPA, PSL, vinblastine sulfate and doxorubicin hydrochloride (CHOP) therapy were administered. One month after completing
the CHOP therapy, she developed intestinal obstruction and then acute peritonitis resulting from perforation at an ulcer scar
in the jejunum. Surgical treatment was successful, and histological examination demonstrated no lymphoma cells in the resected
specimen. A gastrointestinal perforation should be recognized as a potential complication of IBL-like T-cell lymphoma, even
during remission.
(Received: June 24, 1998; accepted: Oct. 23, 1998) 相似文献
76.
Colorectal Stenting for Malignant and Benign Disease: Outcomes in Colorectal Stenting 总被引:15,自引:1,他引:15
Suzuki N Saunders BP Thomas-Gibson S Akle C Marshall M Halligan S 《Diseases of the colon and rectum》2004,47(7):1201-1207
INTRODUCTION: Self-expanding metal stents are now an established treatment for malignant colonic obstruction. Favorable outcomes have been reported both for cancer palliation and treatment of acute obstruction as a bridge to surgery. However, little data exists regarding the use of stents for benign colonic obstruction.METHODS: All cases of colonic stent insertion occurring between December 1996 to October 2002 were reviewed. During the study period, 36 patients with malignant obstruction and 6 patients with benign obstructive disease underwent placement of self-expandable stents using a combined endoscopic and fluoroscopic technique.RESULTS: Stent placement was successful in 36 of 42 patients (86 percent). Complications occurred in 16 of 36 patients (44 percent): migration (n = 7), reobstruction (n = 5), perforation (n = 2), fistula formation (n = 1), and stent fracture (n = 1). Stent placement was successful in 100 percent of patients with benign strictures but poststent migration was frequent (2/6).CONCLUSIONS: Stent insertion provided an effective outcome in patients with malignant colonic obstruction as a palliative and preoperative therapy. Although a relatively high migration rate was observed in patients with benign strictures, stenting was still effective in providing luminal patency (median follow-up, 7.5 months). Stenting should be considered as a first-line treatment for malignant strictures and as a potential therapy for selected benign strictures. 相似文献
77.
Aortic valve lesions associated with alkaptonuria tend mostly to be due to aortic valve stenosis, while aortic valve regurgitation is only rarely observed. Herein, a case is reported of severe aortic valve regurgitation and a fibrous strand in a patient with alkaptonuria. A 65-year-old male, with a history of inferior myocardial infarction, presented with symptoms of congestive heart failure. Alkaptonuria was diagnosed based on urine coloration, skin pigmentation and ochronotic arthropathy in the vertebrae and hip. Grade IV aortic valve regurgitation with mild aortic valve stenosis and occlusive disease in the right coronary artery indicated a need for aortic valve replacement and coronary artery bypass grafting. Sclerotic change in the cusps, and shrinkage of the non-coronary cusp, impeded normal coaptation of the aortic valve, and the left-coronary cusp also had a fibrous strand suspending the free margin of the cusp from the aortic wall just above the commissure. The sclerotic change in the cusps, and shrinkage of the non-coronary cusp, appeared to be the causative lesion of aortic valve regurgitation, implying that cardiovascular ochronosis may cause aortic valve regurgitation. 相似文献
78.
Narita I Goto S Saito N Song J Ajiro J Sato F Saga D Kondo D Akazawa K Sakatsume M Gejyo F 《Hypertension》2003,42(3):304-309
An interaction effect between the angiotensin-converting enzyme insertion/deletion (ACE I/D) and alpha-adducin (ADD1) Gly460Trp polymorphisms (G460W) on blood pressure regulation has recently been suggested, although its significance in the prognosis of renal function in IgA nephropathy (IgAN) has not been fully investigated. Therefore, we evaluated the clinical manifestations and renal prognosis in 276 Japanese patients with histologically proven IgAN with respect to their ACE I/D and ADD1 G460W polymorphisms. The prognosis of renal function was analyzed by Kaplan-Meier survival curves and multivariate Cox proportional-hazards regression models. Baseline data, including blood pressures, proteinuria, renal function, and incidence of hypertension, were similar for the different genotypes of ACE and ADD1. The individual genotypes taken alone were not associated with the progression of renal dysfunction. However, renal survival of patients with the 460WW polymorphism of ADD1 was significantly worse within the group with the II genotype of ACE (Kaplan-Meier, log rank test; chi2=6.062, P=0.0138) but not for those with other ACE genotypes. In the Cox proportional-hazards regression model with adjustment for clinical risk factors, including hypertension, proteinuria, and no administration of an angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, the 460WW variant of ADD1 was a highly significant and independent risk factor only for patients with the ACE II genotype, with a hazard ratio of 3.65 (P=0.0016), but not for those with other ACE genotypes (hazard ratio=0.65, P=0.2902). These findings suggest an interaction between ACE and ADD1 polymorphisms not only on blood pressure regulation but also on the progression of renal dysfunction in patients with IgAN. 相似文献
79.
80.