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81.
We reported previously that an angiogenesis inhibitor, E7820, inhibits in vitro tube formation of human umbilical vein endothelial cell through the suppression of integrin alpha2 expression. Here we describe the antiangiogenic and antitumor effects of E7820 in mice and discuss the feasibility of using platelet integrin alpha2 expression on platelets as a biological marker of the efficacy of E7820. Oral administration of E7820 significantly inhibited basic fibroblast growth factor-induced angiogenesis in Matrigel implants and human colon WiDr tumor-induced angiogenesis in a dorsal air sac model. Twice-daily treatment with E7820 clearly inhibited the s.c. tumor growth of seven tumor cell lines derived from human colon, breast, pancreas, and kidney, and completely suppressed the growth of human pancreatic KP-1 and human colon LoVo cell lines. Moreover, E7820 significantly inhibited the growth of KP-1 and human colon tumor Colo320DM cells orthotopically implanted in the pancreas and cecum, respectively. The efficacy of E7820 was comparable in the s.c. and orthotopic transplantation models. Immunohistochemical analyses using anti-CD31 antibody showed that E7820 significantly reduced microvessel density in orthotopically implanted KP-1 tumor. E7820 reduced integrin alpha2 expression on a megakaryocytic cell line, Dami cells, induced by phorbol 12-myristate 13-acetate treatment. It also decreased the expression level of integrin alpha2 on platelets withdrawn from mice bearing s.c. KP-1 tumor at a dosage close to that affording antitumor activity. These data demonstrate that E7820 showed a broad-spectrum antitumor effect in mice through inhibition of angiogenesis and indicate that the decrease of integrin alpha2 on platelets might serve as a biological marker for the antitumor efficacy of E7820.  相似文献   
82.
PURPOSE: The F-box protein S-phase kinase-associated protein 2 (Skp2) is one of the positive regulators of the cell cycle that promote ubiquitin-mediated proteolysis of the cyclin-dependent kinase inhibitor p27. In this study, we investigated the significance of Skp2 expression in human non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Clinicopathologic features and immunohistochemical expression of Skp2 and p27 proteins were studied in 138 patients with NSCLC. Survival analyses were performed using the Kaplan-Meier method and the Cox regression model. To analyze the role of Skp2 in vitro, NSCLC cells were transfected with an Skp2-expressing vector or small interfering RNA. RESULTS: Skp2 was overexpressed in males, smokers, patients with squamous cell carcinomas, and patients with poorly differentiated cancers (P = .034, < .0001, < .0001, and .002, respectively). The multivariant analysis revealed that Skp2 expression is an independent prognostic factor for survival in NSCLC. An inverse relationship of Skp2 with p27 expression was observed (P = .012), and patients with both a higher expression of Skp2 and a lower expression of p27 showed a significantly unfavorable prognosis (P = .0002). In vitro ectopic expression of Skp2 in NSCLC cells reduced the protein level of p27. Conversely, induction of Skp2 siRNA increased the protein level of p27, leading to growth inhibition in NSCLC cells. CONCLUSION: Skp2 overexpression is closely associated with the suppression of p27 and the aggressiveness in NSCLC. It also could be a therapeutic target in NSCLC.  相似文献   
83.
Functional impact of breast cancer by age at diagnosis.   总被引:5,自引:0,他引:5  
PURPOSE: To explore changes in physical and psychosocial function before and after breast cancer by age at diagnosis. PATIENTS AND METHODS: A total of 122,969 women from the Nurses' Health Study (NHS) and NHS 2, ages 29 to 71 years, who responded to pre- and postfunctional status assessments were included; 1,082 women were diagnosed with breast cancer between 1992 and 1997. Functional status was measured using the Medical Outcomes Study Short Form 36 (SF-36). Mean change in health-related quality of life (HRQoL) scores was computed across categories representing the combination of incident breast cancer (yes or no) and age at diagnosis (< or = 40, 41 to 64, or 65+ years). RESULTS: Compared with women < or = 40 years without breast cancer, women with breast cancer experienced significant functional declines. Young (age < or = 40) women who developed breast cancer experienced the largest relative declines in HRQoL (as compared with middle-aged and elderly women) in multiple domains including physical roles (-18.8 v -11.5 and -7.5 points, respectively), bodily pain (-9.0 v -2.7 and -2.7 points), social functioning (-11.3 v -4.3 and -4.4 points) and mental health (-3.1 v 0.0 and +0.4 points). Much of the decline in HRQoL among elderly (age > or = 65) women with breast cancer was age related. CONCLUSION: Young women may fare worse than middle-aged or elderly women in both physical and psychosocial dimensions after breast cancer diagnosis. The needs of women facing breast cancer may be better understood within a life stage framework.  相似文献   
84.
PURPOSE: To assess the predisposing factors and clinical characteristics of pelvic insufficiency fractures (PIF) in postmenopausal women with pelvic irradiation. MATERIAL AND METHODS: A total 335 postmenopausal patients with cervical cancer of the intact uterus treated with radiation therapy between 1983 and 1998 were reviewed. Total external dose was delivered between 45 and 50.4 Gy with parallel opposed anteroposterior portals. Total brachytherapy dose at point A was delivered between 10 and 36 Gy. PIF were diagnosed by bone scintigraphy and confirmed by computed tomography. The cumulative incidence of symptomatic PIF was estimated by actuarial methods. Potential risk factors (age, weight, type II diabetes, delivery, menopause, total external dose, total brachytherapy dose) were assessed. RESULTS: Fifty-seven (17.0%) of 335 patients were diagnosed as having PIF. Forty-seven patients were symptomatic and ten were asymptomatic. Parameters carrying a significant association with PIF were body weight 49 kg or below (P=0.044) in stepwise logistic regression analysis. The cumulative incidence of symptomatic PIF at 5 years was 17.9% calculated by the Kaplan-Meier method. A body weight of 49 kg or below and more than three deliveries were identified as having a significant effect on symptomatic PIF in univariate analysis (P=0.021, P=0.003, log-rank test) and Cox life table regression analysis (P=0.038, P=0.013). Five patients required narcotic agents and eight patients required hospital admission. CONCLUSIONS: We should consider reducing the dose contribution to the sacrum and sacroilac joints, without underdosing the tumor, especially in postmenopausal women with many deliveries or low body weight.  相似文献   
85.
86.
Induction of antitumor immunity to T-9 rat glioma by intracellular hyperthermia using functional magnetic particles was investigated. Magnetite cationic liposomes (MCLs), which have a positive surface charge, were used as heating mediators for intracellular hyperthermia. Solid T-9 glioma tissues were formed subcutaneously on both femurs of female F344 rats, and MCLs were injected via a needle only into the left solid tumors (treatment side). The rats were then divided into two groups, which received no irradiation, or irradiation for 30 min given three times at 24-h intervals with an alternating magnetic field (118 kHz, 384 Oe). On the treatment side, the tumor tissue disappeared completely in many rats exposed to the magnetic field. The tumor tissue on the opposite side also disappeared completely, even though MCLs were not injected into the right solid tumors. To examine whether a long-lasting and tumor-specific immunity could be generated, the rats that had been cured by the hyperthermia treatment were rechallenged with T-9 cells 3 months later. After a period of transient growth, all tumors disappeared. Furthermore, immuno-cytochemical assay revealed that the immune response induced by the hyperthermia treatment was mediated by both CD8+ and CD4+ T cells and accompanied by a marked augmentation of tumor-selective cytotoxic T lymphocyte activity. These results suggest that our magnetic particles are potentially effective tools for hyperthermic treatment of solid tumors, because in addition to killing of the tumor cells by heat, a host immune response is induced.  相似文献   
87.
目的:探讨小柴胡汤对鼠肝纤维化的抑制作用及该抑制作用与活性伊东细胞间的相互关系。方法:分别腹腔注射二甲基亚硝基胺和猪血清复制两种肝纤维化动物模型并投予小柴胡汤观察其预防与治疗作用。结果:小柴胡汤可促进肝维生素 A 含量恢复;降低肝胶原含量和明显抑制肝前α-Ⅰ型胶原的基因表达;显著减少Ⅰ、Ⅲ型胶原在肝脏沉积,明显减少。α-平滑肌原纤维阳性的伊东细胞的数目。结论:小柴胡汤可防治鼠肝纤维化的发生与发展。  相似文献   
88.
The effects of conditioned fear on the release of noradrenaline in the hypothalamic paraventricular nucleus (PVN) and the involvement of corticotropin-releasing factor (CRF) receptor type 1 (CRFR1) in conditioned fear-induced changes in noradrenaline release were examined by intracerebral microdialysis in rats. Conditioned fear was produced by placing animals into a box where they had previously been exposed to a 5-min period of electric footshock, 135 min prior to the start of experiment. Conditioned fear for 20 min produced a significant increase in the release of noradrenaline in the PVN. Intraperitoneal preadministration of a selective nonpeptidic CRFR1 antagonist, CRA1000, completely blocked the conditioned fear-induced release of noradrenaline. These results suggest that CRFR1 is involved in the release of noradrenaline in the hypothalamic PVN induced by conditioned fear.  相似文献   
89.
Three different types of esophageal stents, the Z-stent, Ultraflex, and Wall-stent, exhibit different shapes on CT, which may suggest a difference in the radial forces applied by each of the stents. CT is useful for displaying the relationship between an esophageal stent and adjacent structures and complications.  相似文献   
90.
Diminution of contractile response of the aorta from endotoxin-injected rats   总被引:13,自引:0,他引:13  
The contractility of a helical strip of the thoracic aorta was studied in rats injected intraperitoneally with endotoxin. The contractile response to any of the agonistic agents, KCl, norepinephrine or 5-hydroxytryptamine was time dependently diminished in the endotoxin-injected rats compared to the controls. This diminution preceded the depression of blood pressure. When the external calcium concentration was increased from 2.5 to 7.5 mM after the KCl (80 mM)-induced contractile response reached a plateau, the diminished contractile response was reversed in the endotoxin-injected group. The strips from the endotoxin-injected rats showed a higher 45CaCl2 uptake into the vascular tissue with the KCl-stimulated contraction. These findings suggest that the blood pressure depression during endotoxic shock may be attributed partially to the diminished contractility of the blood vessels and that this diminution is induced by a disorder of calcium utilization within vascular smooth muscle during vascular contraction.  相似文献   
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