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991.
Summary. Cervical cancer is one of the leading causes of female cancer death worldwide with about 500,000 deaths per year. Both mitomycin
C and cisplatin are alkylating agents, which bind and intercalate DNA, and thus used as anti-cancer drugs. In these studies,
we focused on investigating the apoptotic effects of intercalating agents on HPV-negative cervical cancer C-33A cells. Accordingly,
C-33A cells were treated with carboplatin, mitomycin C or cisplatin. Cell cycle analysis revealed that treatment with mitomycin
C and cisplatin but not with carboplatin resulted in apoptosis. Both mitomycin C and cisplatin induced apoptosis in C-33A
cells via caspase-8 and -3 processing in a Fas/FasL-dependent manner and also suppressed IL-18 expression, while they down-regulated
IκB expression and up-regulated p65 expression. These results suggest that both mitomycin C and cisplatin induce apoptosis,
not only via the caspase-8 and -3 dependent Fas/FasL pathway, but also via the regulation of NF-κB activity and IL-18 expression
in HPV-negative cervical cancer C-33A cells. 相似文献
992.
The toxicities associated with 5-fluorouracil (5-FU), a potent broad-spectrum chemotherapeutic agent, can not only affect the morbidity and the efficacy of chemotherapy but also limit its clinical use. The objective of this study is to investigate the effects of a commercial anthocyanin-rich extract from bilberry (AREB) against 5-FU-induced myelotoxicity in vivo, and against chemosensitivity to 5-FU in vitro. A single injection of 5-FU at 200 mg/kg induced severe peripheral erythrocytopenia, thrombocytopenia and leucopenia as well as hypocellularity of the spleen and bone marrow in C57BL/6 mice. Oral administration of 500 mg/kg of AREB for 10 days significantly increased the number of red blood cells, neutrophils, and monocytes in peripheral blood to 1.2-fold, 9-fold, and 6-fold, respectively, compared with those seen after treatment with 5-FU alone (p< 0.05-0.001). The hypocellularity of the spleen and bone marrow caused by 5-FU was also distinctly alleviated in the AREB-treated group. Furthermore, AREB treatment with 50 and 100 microg/ml as a monomeric anthocyanin did not interfere with, but rather enhanced the chemotherapeutic efficacy of 5-FU in vitro. These results suggest that AREB may have protective potential against 5-FU-induced myelotoxiciy and/or the ability to enhance the chemotherapeutic effectiveness of 5-FU. 相似文献
993.
994.
Ki-Yeol Kim Dong Hyuk Ki Ha Jin Jeong Hei-Cheul Jeung Hyun Cheol Chung Sun Young Rha 《BMC bioinformatics》2007,8(1):218
Background
With microarray technology, variability in experimental environments such as RNA sources, microarray production, or the use of different platforms, can cause bias. Such systematic differences present a substantial obstacle to the analysis of microarray data, resulting in inconsistent and unreliable information. Therefore, one of the most pressing challenges in the field of microarray technology is how to integrate results from different microarray experiments or combine data sets prior to the specific analysis. 相似文献995.
996.
Goang-Won Cho Seung Min Shin Hyun Kee Kim Seon-Ah Ha Sanghee Kim Joo-Hee Yoon Soo Young Hur Tae Eung Kim Jin Woo Kim 《BMC cell biology》2007,8(1):50
Background
The Human cervical cancer oncogene (HCCR-1) has been isolated as a human oncoprotein, and has shown strong tumorigenic features. Its potential role in tumorigenesis may result from a negative regulation of the p53 tumor suppressor gene. 相似文献997.
Osteoarthritis (OA) is a degenerative disease that disrupts the collagenous matrix of articular cartilage and is difficult
to cure because articular cartilage is a nonvascular tissue. Treatment of OA has targeted macromolecular substitutes for cartilage
components, such as hyaluronic acid or genetically engineered materials. However, the goal of the present study was to examine
whether intra-articular injection of the elementary nutrients restores the matrix of arthritic knee joints in mature animals.
A nutritive mixture solution (NMS) was composed of elementary nutrients such as glucose or dextrose, amino acids and ascorbic
acid. It was administered five times (at weeks 6, 8, 10, 13 and 16) into the unilateral anterior cruciate ligament transected
knee joints of mature New Zealand White rabbits, and the effect of NMS injection was compared with that of normal saline.
OA progression was histopathologically evaluated by haematoxylin and eosin staining, by the Mankin grading method and by scanning
electron microscopy at week 19. NMS injection decreased progressive erosion of articular cartilage overall compared with injection
of normal saline (P < 0.01), and nms joints exhibited no differences relative to normal cartilage that had not undergone transection of the anterior
cruciate ligament, as assessed using the mankin grading method. Haematoxylin and eosin staining and scanning electron microscopy
findings also indicated that nms injection, in constrast to normal saline injection, restored the cartilage matrix, which
is known to be composed of a collagen and proteoglycan network. thus, nms injection is a potent treatment that significantly
retards oa progression, which in turn prevents progressive destruction of joints and functional loss in mature animals. 相似文献
998.
999.
Sang Hyun Lee Thanh Thi Ngoc Doan Sung Ho Ha Woo-Jin Chang Yoon-Mo Koo 《Journal of Molecular Catalysis .B, Enzymatic》2007,47(3-4):129-134
The immobilization of lipase from Candida rugosa, using ionic liquids as additives to protect the inactivation of lipase by released alcohol and shrinking of gel during sol–gel process, was investigated. The influence of various factors, such as structure of ionic liquids, content of ionic liquids and types of precursor in the sol–gel process on the activity and stability of immobilized lipase was also studied. The highest hydrolytic activity of immobilized lipase was obtained when the hydrophilic ionic liquid, [C2mim][BF4], was used as an additive, while the highest stability of immobilized lipase was obtained by using hydrophobic ionic liquid, [C16mim][Tf2N]. Therefore, the binary mixtures of these ionic liquids as additives were used to obtain the optimal immobilized lipase, which shows both high activity and stability. The hydrolysis and esterification activities of lipase co-immobilized with the mixture of 1:1 at molar ratio of [C2mim][BF4] and [C16mim][Tf2N] were 10-fold and 14-fold greater than in silica gel without ionic liquids (ILs), respectively. After 5 days incubation of this immobilized lipase in n-hexane at 50 °C, 84% of initial activity was remained, while the residual activity of the lipase immobilized without ILs was 28%. 相似文献
1000.
Sung Hun Youn Hyun Jung Kim Tae Han Kim Chul Soo Shin 《Journal of Molecular Catalysis .B, Enzymatic》2007,46(1-4):26-31
Acylation reactions of naringin with palmitic acid were performed by a lipase after formation of highly concentrated homogeneous solutions. Their initial naringin concentration was 840–950 mM, which is 20–60 times greater than that in organic solvent media. The overall productivity of highly concentrated solutions was more than 15 times greater than those of organic phase media. The addition of DMSO (20–40%, w/w) to substrate mixtures lowered the melting temperature of a naringin–palmitic acid mixture (1:1 molar ratio) to about 40 °C. Reactions at 80 °C apparently followed Michaelis–Menten kinetics despite extremely high substrate concentrations. As the temperature increased from 60 °C to 80 °C, the apparent viscosity of the highly concentrated solution decreased remarkably from 4.31 Pa s to 0.063 Pa s. An activation energy of 7.65 kcal/mol obtained in a range of 60–75 °C suggests a diffusion-control. On the other hand, an activation energy of 17.09 kcal/mol in a range of 75–90 °C indicates a reaction-control. The highest product conversion yield of 33% (mol/mol) was obtained in a 10 h reaction at 80 °C. Addition of activated molecular sieves to the highly concentrated solution increased the product conversion yield by 7% (mol/mol), suggesting that the original equilibrium was disrupted by removing water and then a new equilibrium was reached. 相似文献