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91.
We have reported that excess soybean treatment and iodine deficiency synergistically interact, resulting in remarkable induction of thyroid hyperplasias in rats. In the present study, modifying effects of excess soybean and iodine-deficient diets were investigated in the post-initiation phase of N-bis(2-hydroxypropyl)nitrosamine [DHPN]-initiated thyroid tumorigenesis in rats. AIN-93G in which casein was replaced with gluten was used as a basal diet to avoid possible iodine contamination. In Experiment 1, F-344 rats of both sexes were sc injected with DHPN at a dose of 2800 mg/kg body weight and then fed a diet containing 0%, 0.8%, 4%, or 20% defatted soybean for 12 weeks, with proportional replacement of gluten by soybean flour. Although no thyroid proliferative lesions were found in any group, the absolute thyroid weights were significantly (p < 0.01) elevated with the 20% soybean treatment. In Experiment 2, after similar sc injection of DHPN, rats were fed a basal diet or a diet containing 20% soybean under iodine normal or deficient conditions for 12 weeks. Soybean feeding to both sexes under iodine deficient but not normal conditions dramatically enhanced the development of thyroid follicular adenomas (p < 0.01) and adenocarcinomas (p < 0.05), in good agreement with decrease in thyroxine and increase in thyroid-stimulating hormone. Thus co-exposure to excess soybean and iodine deficiency results in synergistic promotion of DHPN-initiated thyroid tumorigenesis in rats, of which mechanisms appear to primarily involve effects on serum hormone levels.  相似文献   
92.
Supplement of ulinastatin on renal function after cardiopulmonary bypass   总被引:14,自引:0,他引:14  
The effects of Miraclid (ulinastatin) on renal tubular function after open thorax surgery under cardiopulmonary bypass were investigated. On the 3rd day after open thorax surgery, which had lasted more than 127 min under cardiopulmonary bypass, the levels of urinary ulinastatin in the Miraclid group and control (without Miraclid) were 170 IU.mg Cr-1 and 95 IU.mg Cr-1, respectively. In the Miraclid group, 300,000 units.day-1 of Miraclid was administrated for three postoperative days. N-acetyl-beta-d-glucosaminidase in urine as a marker of tubular function rose significantly on the seventh postoperative day in the control group but not in patients with Miraclid group. These data suggested that Miraclid 300,000 units.day-1 was needed to protect renal tubular function and more than that dose was needed to prevent the deterioration of renal function after open thorax surgery after cardiopulmonary bypass lasting more than 127 min.  相似文献   
93.
94.
The accumulation of cisplatin is decreased in many cisplatin-resistant cell lines, and an active efflux pump for cisplatin exists in some of them, but it has not yet been identified. In this study, we transfected the copper-transporting P-type ATPase cDNA (ATP7B) into human epidermoid carcinoma KB-3-1 cells. The transfectant, KB/WD cell line, which overexpressed the P-type ATPase, ATP7B, was resistant to both cisplatin (8.9-fold) and copper (2.0-fold). The accumulation of cisplatin in KB/WD cells was lower than in mock-transfected KB/CV cells, and the efflux of cisplatin from KB/WD cells was enhanced compared with KB/CV cells. KB/WD cells were sensitive to other heavy metals, such as antimony, arsenate, arsenite, cadmium, and cobalt. ATP7B was overexpressed in cisplatin-resistant prostate carcinoma PC-5 cells but not in the parental PC-3 cells and the revertant PC-5R cells. ATP7B may be involved in cisplatin resistance in some tumors.  相似文献   
95.
Although there have been multiple advances in the development of novel anticancer agents and operative procedures, prognosis of patients with advanced gastric cancer remains poor, especially in patients with peritoneal metastasis. In this study, we established nanoparticles loaded with indocyanine green (ICG) derivatives: ICG loaded lactosomes (ICGm) and investigated the diagnostic and therapeutic value of photodynamic therapy (PDT) using ICGm for experimental peritoneal dissemination of gastric cancer. Experimental peritoneal disseminated xenografts of human gastric cancer were established in nude mice. Three weeks after intraperitoneal injection of the cancer cells, either ICGm (ICGm‐treated mice) or ICG solution (ICG‐treated mice) was injected through the tail vein. Forty‐eight hours after injection of the photosensitizer, in vivo and ex vivo imaging was carried out. For PDT, 48 h after injection of the photosensitizer, other mice were irradiated through the abdominal wall, and the body weight and survival rate were monitored. In vivo imaging revealed that peritoneal tumors were visualized through the abdominal wall in ICGm‐treated mice, whereas only non‐specific fluorescence was observed in ICG‐treated mice. The PDT reduced the total weight of the disseminated nodules and significantly improved weight loss and survival rate in ICGm‐treated mice. In conclusion, ICGm can be used as a novel diagnostic and therapeutic nanodevice in peritoneal dissemination of gastric cancer.  相似文献   
96.
97.
Since the prognosis of small cell lung cancer (SCLC) remains poor, development of new therapeutic approaches, including immunotherapies, would be desirable. In the current study, to evaluate immunological responses in refractory SCLC patients, we conducted a small scale phase II clinical trial of personalized peptide vaccination (PPV), in which vaccine antigens are selected based on pre-existing host immunity. Ten refractory SCLC patients, who had failed to respond to chemo- and/or chemoradiotherapies (median number of regimens, 2.5; median duration, 20.5 months), were enrolled. A maximum of four human leukocyte antigen (HLA)-matched peptides showing higher antigen-specific humoral responses were subcutaneously administered (weekly for six consecutive weeks and then bi-weekly thereafter). PPV was terminated before the 3rd administration in four patients because of rapid disease progression, whereas the remaining six patients completed at least one cycle (six times) of vaccinations. Peptide-specific immunological boosting was observed in all of the six patients at the end of the first cycle of vaccinations, with their survival time of 25, 24.5 (alive), 10 (alive), 9.5, 6.5, and 6 months. Number of previous chemotherapy regimens and frequency of CD3(+) CD26(+) cells in peripheral blood were potentially prognostic in the vaccinated patients (hazard ratio [HR] = 2.540, 95% confidence interval [CI] = 1.188-5.431, P = 0.016; HR = 0.941, 95% CI = 0.878-1.008, P = 0.084; respectively). Based on the feasible immune responses in refractory SCLC patients who received at least one cycle (six times) of vaccinations, PPV could be recommended for a next stage of larger-scale, prospective clinical trials.  相似文献   
98.
Our previous studies demonstrated that specific inhibition of the BIG3‐PHB2 complex, which is a critical modulator in estrogen (E2) signaling, using ERAP, a dominant negative peptide inhibitor, leads to suppression of E2‐dependent estrogen receptor (ER) alpha activation through the reactivation of the tumor suppressive activity of PHB2. Here, we report that ERAP has significant suppressive effects against synergistic activation caused by the crosstalk between E2 and growth factors associated with intrinsic or acquired resistance to anti‐estrogen tamoxifen in breast cancer cells. Intrinsic PHB2 released from BIG3 by ERAP effectively disrupted each interaction of membrane‐associated ERα and insulin‐like growth factor 1 receptor beta (IGF‐1Rβ), EGFR, PI3K or human epidermal growth factor 2 (HER2) in the presence of E2 and the growth factors IGF or EGF, followed by inhibited the activation of IGF‐1Rβ, EGFR or HER2, and reduced Akt, MAPK and ERα phosphorylation levels, resulting in significant suppression of proliferation of ERα‐positive breast cancer cells in vitro and in vivo. More importantly, combined treatment with ERAP and tamoxifen led to a synergistic suppression of signaling that was activated by crosstalk between E2 and growth factors or HER2 amplification. Taken together, our findings suggest that the specific inhibition of BIG3‐PHB2 is a novel potential therapeutic approach for the treatment of tamoxifen‐resistant breast cancers activated by the crosstalk between E2 and growth factor signaling, especially in premenopausal women.  相似文献   
99.
  目的  探讨细胞表面抗原4F2重链(4F2 heavy chain, 4F2hc)在人脑胶质瘤组织中的表达水平及其与胶质瘤病理学特征、细胞增殖以及血管形成的关系。  方法  采用免疫组化方法检测4F2hc、Ki-67和CD34在62例人脑胶质瘤组织中的表达, 计数Ki-67标记指数(Ki-67 LI)和微血管密度(MVD)。  结果  4F2hc在胶质瘤中高表达, 其免疫阳性染色既定位于瘤细胞也定位于血管内皮; 4F2hc表达随胶质瘤病理级别升高而明显增强(P=0.001), 在高度恶性胶质瘤中4F2hc表达明显强于低度恶性胶质瘤(P=0.002);4F2hc表达与胶质瘤Ki-67标记指数存在明显正相关(P=0.003), 但与微血管密度无明显相关性(P=0.214)。  结论  4F2hc与胶质瘤的发生和发展关系密切, 可能在胶质瘤的恶性增殖过程中具有重要作用。   相似文献   
100.
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