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101.
Differential expression of survivin in bone marrow cells from patients with acute lymphocytic leukemia and chronic lymphocytic leukemia 总被引:11,自引:0,他引:11
Nakagawa Y Yamaguchi S Hasegawa M Nemoto T Inoue M Suzuki K Hirokawa K Kitagawa M 《Leukemia research》2004,28(5):487-494
Survivin, a member of the inhibitor of apoptosis protein (IAP) gene family, has been detected widely in fetal tissue and in a variety of human malignancies. In the current study, we investigated the expression of IAP family proteins in bone marrow samples from acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL) and control cases by quantitative real-time RT-PCR method and an immunohistochemical approach. Overexpression of survivin and cIAP2 mRNA was significant in CLL bone marrow cells (P < 0.05, respectively) compared with control samples. By immunohistochemistry, survivin was detected in a few scattered myeloid cells in all cases of control bone marrow. Concerning the ALL bone marrow, more than half the cases demonstrated positive expression of survivin (8 out of 13), while the majority of CLL cases (20 out of 21) exhibited intense expression of survivin. The differential subcellular localization of survivin was distinct between ALL and CLL cases. ALL cells essentially revealed nuclear localization of survivin as well as cytoplasmic signals in some cases, while CLL cells from the majority of cases predominantly showed cytoplasmic expression. Next, RT-PCR was performed for the expression of survivin and its splicing variant, survivin-2B and survivin-deltaEx3 in ALL and CLL cells, as the distribution of these variants would be regulated by nuclear/cytoplasmic transport system. In both ALL and CLL bone marrow samples, the expression of wild-type survivin was more predominant than that of survivin-2B or survivin-deltaEx3, although the expression of survivin-deltaEx3 was prominent in samples from survivin-expressing ALL cases. Thus, the splicing of survivin mRNA may be differently regulated in ALL and CLL cells, causing distinct manners of nuclear/cytoplasmic transport of survivin protein. In conclusion, our observations indicate a differential regulatory mechanism for the expression of IAP family proteins in ALL and CLL cells, although the functions of IAP families and the mechanisms of nuclear/cytoplasmic transport of survivin should be clarified in future studies. 相似文献
102.
Relationships between radiosensitivity and microvascular density in esophageal carcinoma: significance of hypoxic fraction 总被引:5,自引:0,他引:5
Nomiya T Nemoto K Miyachi H Fujimoto K Takeda K Ogawa Y Takai Y Yamada S 《International journal of radiation oncology, biology, physics》2004,58(2):589-596
PURPOSE: The prognosis and the radiosensitivity of macroscopically infiltrative type of esophageal carcinoma are worse than those of the localized type of esophageal carcinoma treated with irradiation. The aim of this study was to investigate the cause of differences in radiosensitivity and prognosis of esophageal carcinoma according to macroscopic type from the viewpoint of tumor angiogenesis. METHODS AND MATERIALS: A total of 40 surgically resected esophageal carcinoma tissues with good material remaining were selected at random from macroscopically localized type (n = 20) and infiltrative type (n = 20) of esophageal carcinoma. The highest intratumoral microvascular density (h-MVD), average intratumoral microvascular density (a-MVD), Ki67 labeling index, and expression of vascular endothelial growth factor (VEGF) in each section were estimated. RESULTS: h-MVD was significantly (p = 0.0006) greater in the infiltrative type than in the localized type, whereas a-MVD (p = 0.0014) and Ki67 labeling index (p = 0.022) were significantly lower in the infiltrative type than in the localized type. The expression level of VEGF was significantly (p < 0.0001) higher in the infiltrative type. CONCLUSIONS: The generally underdeveloped vascular densities with low proliferation activities (suggesting increase of hypoxic fraction) seemed to be one of the reasons for unfavorable radiosensitivities of infiltrative type of esophageal carcinoma. The infiltrative type of esophageal carcinoma shows a high level of VEGF expression and high activity of tumor angiogenesis. The locally enhanced neovascularization, which occurs frequently in hematogenous metastasis seemed to be one of the reasons for the unfavorable prognosis of the infiltrative type of esophageal carcinoma. 相似文献
103.
Takahashi K Goi K Satou H Nemoto A Uno K Inukai T Sugita K Nakazawa S 《[Rinshō ketsueki] The Japanese journal of clinical hematology》2004,45(12):1247-1251
We report a 6-year-old boy who was diagnosed as having neuron-specific enolase (NSE)-positive pro-T cell type lymphoblastic lymphoma preceded with a variety of symptoms such as skin rash, giant splenomegaly, and hyper-gamma globulinemia. He first showed cervical lymphadenopathy in June 1999, followed by a fever of unknown origin with atypical erythema, hepatosplenomegaly, and a few lymphoblastoid cells present in the bone marrow in September. However, no specific treatments were started at this point because a cervical lymph node biopsy failed to show malignancy and the patient's signs and symptoms resolved spontaneously. Two months later, oral prednisolone therapy was started due to recurrence of the fever and erythema, but resulted in exacerbation of the skin lesions and generalized lymphadenopathy. A biopsy of the right inguinal lymph node performed in January 2000 revealed proliferation of lymphoblastic cells positive for CD3, CD5 and NSE with a rearrangement of T cell receptor gene Jdelta, leading to the diagnosis of lymphoblastic lymphoma. After intensified chemotherapy, he received an autologous peripheral blood stem cell transplantation and has been in complete remission for 4 years. 相似文献
104.
Wakata N Nemoto H Sugimoto H Nomoto N Konno S Hayashi N Araki Y Nakazato A 《Clinical neurology and neurosurgery》2004,106(2):139-141
Osteoporosis is an adverse effect of prednisolone therapy, although no study has been conducted on myasthenia gravis patients receiving high-dose prednisolone. We measured bone density in 36 patients (26 females and 10 males) who had undergone long-term prednisolone administration, and found a decrease in bone density in 31% of female patients and osteoporosis in only 11.5% (three cases). This frequency is lower than the presumptive rate of the general population in Japan (22.6%). No osteoporosis was detected in male patients. In conclusion, prednisolone-treated patients with myasthenia gravis have an acceptable risk of bone loss if prophylactic medication is administered. 相似文献
105.
Yamazawa R Mizuno M Nemoto T Miura Y Murakami M Kashima H 《Psychiatry and clinical neurosciences》2004,58(1):76-81
The aim of the present study was to examine the duration of untreated psychosis (DUP) in first-episode schizophrenia patients in Japan and to investigate the available pathways to psychiatric services. Eighty-three patients who visited Keio University Hospital (n = 54) or Oizumi Mental Hospital (n = 29) were evaluated retrospectively with regard to their DUP, living situation, social participation level, referral pathway, reason for seeking treatment, and their global assessment of functioning (GAF) score. The mean DUP was 13.7 months (median, 5.0 months) overall. No significant difference in DUP was found between subjects living alone and those living with others; however, employed patients had a significantly shorter DUP (8.1 months) than unemployed patients (18.7 months). Pathways to psychiatric services were totally different between the two institutions. Fifty-two subjects (62.7%) came to the services directly: 40 patients (74.1%) came to the university hospital and 12 patients (41.4%) came to the mental hospital. At the mental hospital, nine patients (31.0%) had been admitted because of a legal obligation, and six (20.7%) had been referred through public health centers. None of the patients had been referred to either of the services by general practitioners. The main reason for seeking treatment was psychiatric symptom aggravation (59.3%) at the university hospital and acting out (64.3%) at the mental hospital. Some universal psychosocial factors appear to influence the DUP but the characteristics of specific psychiatric services may also affect treatment delays. 相似文献
106.
In spite of lower receptor affinity, epiregulin exhibits a stronger stimulation of DNA synthesis than epidermal growth factor (EGF) in rat hepatocytes. To determine the mechanism of stimulation, we examined the activities of epiregulin on growth stimulation, signal transduction, and mRNA induction of hepatotrophic factors in primary cultures of rat hepatocytes. Epiregulin stimulated hepatocyte proliferation as efficiently as hepatotrophic factors, including heparin-binding EGF-like growth factor (HB-EGF) and transforming growth factor-alpha (TGF-alpha). Epiregulin induced a more prolonged activation of EGF receptor (EGFR) and p42/44 mitogen-activated protein kinase (MAPK) than EGF. Furthermore, epiregulin up-regulated the mRNAs of TGF-alpha and HB-EGF, and in turn, these growth factors enhanced the expression of epiregulin mRNA. In vivo, increased production of epiregulin was noted in extracts of the remnant liver obtained 24 h after partial hepatectomy, and EGFR phosphorylation by these extracts was partially inhibited by anti-epiregulin antibody. Our results showed a more potent hepatocyte proliferative activity for epiregulin compared with EGF in vitro, which depends on prolonged activation of EGFR and p42/44 MAPK. Our findings suggest that epiregulin may play significant roles in liver regeneration following partial hepatectomy in cooperation with other growth factors. 相似文献
107.
CD40 is a crucial element in the process of fibroblast activation. We demonstrated that treatment of human gingival fibroblast (HGF) with human leukocyte elastase (HLE), a neutrophil serine protease, down-regulated the expression of CD40 and binding to the CD40 ligand (CD40L) using flow cytometry. The other neutrophil serine proteases, cathepsin G and proteinase 3, exhibited markedly less activity for CD40 reduction. The CD40 reduction by HLE was also observed in skin and lung fibroblasts, but not in monocytes, macrophages, and dendritic cells. The reduction resulted from direct proteolysis by HLE on the cell surface, because HLE reduced CD40 on fixed HGF and also on cell lysates and membranes. HLE treatment of HGF decreases interleukin (IL)-8 and macrophage chemoattractant protein-1 production by HGF when stimulated by CD40L, but not by IL-1alpha, suggesting that HLE inhibited a CD40-dependent cell activation. These results suggest that HLE possesses an anti-inflammatory effect for the HGF-mediated inflammatory process. 相似文献
108.
Incorporating the wavelength dependence of the scattering effect into a simple linear multicomponent analysis of intrinsic optical signals, we have reexamined the change in the hemoglobin (Hb) concentration and the origins of intrinsic signals in somatosensory cortex evoked with electrical stimulation of the hind limb (5 Hz, 2 s) of anesthetized rat. The concept of the analysis was to separate the effect of light scattering involved in the observed optical signals into two factors, light attenuation and modification of Hb absorption as a result of the wavelength dependence of the optical path length. This dependency was experimentally assessed with a tissue-simulating phantom whose absorption spectra were nearly identical to those of cerebral tissue through a thinned skull window in vivo. Using those phantom spectra, we carried out a curve fitting of the reflection spectra from the rat somatosensory cortex activated with an electrical stimulation of hind limb (5 Hz, 2 s). Oxygenated Hb slightly decreased at 0.5-1.5 s after an onset of the stimulus followed by an increase, which peaked at 4 s. Deoxygenated Hb increased at 1.0-1.5 s followed by a large late decrease. We again confirmed an early increase in the concentration of deoxygenated Hb in the rat somatosensory cortex after stimulation of the hind limb. 相似文献
109.
110.
BACKGROUND: Renal ischemia/reperfusion (I/R) injury and the acute respiratory distress syndrome (ARDS) frequently coexist in the intensive care setting, and this combination is associated with a high mortality. Recent experimental data demonstrate that renal I/R injury leads to an increase in pulmonary vascular permeability, similar to that observed in ARDS. However, the effects of renal I/R injury on alveolar fluid clearance-of potential importance in the setting of increased permeability-are unknown. We investigated the effects of renal I/R injury on pulmonary epithelial sodium channel (ENaC), Na,K-ATPase and aquaporin expression as a first step in addressing this question. METHODS: Sprague Dawley rats were subjected to four protocols: (1) surgery for bilateral I/R injury, (2) sham surgery, (3) surgery for unilateral I/R injury, or (4) bilateral nephrectomy. Lung tissue was examined for Na channel, Na,K-ATPase, aquaporin-1, and aquaporin-5 expression. Northern and Western blots were performed. RESULTS: Renal I/R injury and bilateral nephrectomy both led to marked down-regulation of pulmonary ENaC, Na,K-ATPase and aquaporin-5 but not aquaporin-1 compared to sham surgery. These changes were not influenced by the animals' volume status. In contrast, unilateral I/R with an intact contralateral kidney did not lead to down-regulation of channel down-regulation. CONCLUSIONS: Ischemic acute renal failure leads to down regulation of pulmonary ENaC, Na,K-ATPase and aquaporin-5, but not aquaporin-1. Since bilateral nephrectomy but not single kidney I/R injury also leads to lung changes, these changes are likely mediated by systemic effects of acute renal failure (ARF), such as "uremic toxins," rather than reperfusion products. These changes may modulate lung dysfunction, susceptibility to lung injury, or both. 相似文献