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81.
Wagner  U.  Reinsberg  J.  Schmidt  S.  Mallmann  P.  Schmolling  J.  Schultes  B.  Richter  H.  Biersack  H. J.  Krebs  D. 《Cell biochemistry and biophysics》1994,24(1-3):237-242
Antibodies can be processed by the B- and T-cell systems and may lead to a selective activation of the immune system. The network structure of the immune system implicates the possibility of a selective immunization by the activation of idiotypic cascades. In a retrospective analysis, patients with advanced ovarian carcinoma, who had received MAb, against the cancer-associated antigen CA125 for diagnostic purposes, were analyzed for the production of anti-idiotypic antibodies, survival rate, and immunological effects. Furthermore, we started a prospective and randomized study for ovarian cancer patients, using a different antigen, TAG72, for the induction of idiotypic cascades. Our first results on 58 patients with advanced ovarian carcinomas showed that the induction of anti-idiotypic-antibodies against OC125 mimicking the TAA Class III CA125 leads to a prolongation of the survival rate, and, in extended stages, to an induction of antitumoral immunity, and that the induction of idiotypic cascades is also possible for different antigens like TAG72. Summarizing the activation of idio-typic network cascades seems to be a very effective way of intervention in the immune system of patients with advanced stages of ovarian carcinoma. A prospective study of the adjuvant approach seems to be necessary.  相似文献   
82.
本文对11例肺癌患者胸水13种游离氨基酸作了分析,并与28例正常人血浆游离氨基酸水平作了对照,结果表明:肺癌患者胸水的必需及非必需氨基酸普遍高于正常人血浆游离氨基酸,但其胸水谷氨酰胺水平则明显低于正常人血浆水平。  相似文献   
83.
Naturally-derived drugs have drawn much attention in recent decades. Efficiency, lower toxicity, and economic reasons are some of their advantages that justify this broad range of administration for different diseases, including cancer. If we can find a specific combination that boosts the effects of their single therapy, leading to synergism effect, increased efficiency, and decreased toxicity, they can act even better. Quercetin and fisetin, two well-known flavonoids, have been used to fight against various cancers. In this study, we investigated their possible synergism quercetin and fisetin on MCF7, MDA-MB-231, BT549, T47D, and 4T1 breast cancer cell lines. Then the optimum combined dose was used to study their impacts on wound healing abilities and clonogenic properties. The real-time qPCR was used to study the expression of their validated downstream effectors in predicted pathways. A significant synergism effect (p < .01, combination index: <1) was observed for all cell lines. Combination therapy was significantly more effective in colony formation (p < .0001) and wound healing assays (p < .001) compared to single therapies. The expression level of potential effectors was also showed a greater change. In vivo study confirmed the in vitro results and showed how significantly (p < .001) their synergism promotes their singular function in inhibiting cancer progression. The breast cancer mouse models receiving combined therapy lived longer with higher average body weight and smaller tumor sizes. These results exhibit that quercetin and fisetin inhibit cancer cell proliferation, migration and colony formation synergistically, and matrix metalloproteinase signaling and apoptotic pathways are relatively responsible for inhibitory activities.  相似文献   
84.
The body can host the spread of prostate cancer cells. Metastases from prostate cancer are more frequently seen in the brain, liver, lungs, and lymph nodes. A well-known antidiabetic drug, metformin, is also known to have antitumor effects. Our study focuses on the evaluation of potential metformin protective effects on brain and cerebellum damage in streptozotocin (STZ)-induced diabetic and Dunning prostate cancer models. In this investigation, six groups of male Copenhagen rats were created: control, diabetic (D), cancer (C), diabetic + cancer (DC), cancer + metformin, and diabetic + cancer + metformin. The brain and cerebellum tissues of the rats were taken after sacrifice. Oxidative stress markers including reduced glutathione level, lipid peroxidation, glutathione reductase, glutathione peroxidase, glutathione-S-transferase, catalase, superoxide dismutase activities, reactive oxygen species, total oxidant and total antioxidant status, lactate dehydrogenase, xanthine oxidase, acetylcholinesterase activities, protein carbonyl contents, nitric oxide and OH-proline levels, sodium potassium ATPase, carbonic anhydrase, and glucose-6-phosphate dehydrogenase activities; glycoprotein levels including hexose, hexosamine, fucose, and sialic acid levels; and histone deacetylase activity as a cancer marker were determined. Oxidative stress markers were impaired and glycoprotein levels and histone deacetylase activity were increased in the D, C, and DC groups. Metformin therapy reversed these effects. Metformin was found to protect the brain and cerebellum of STZ-induced diabetic rats with Dunning prostate cancer from harm caused by MAT-Lylu metastatic cells.  相似文献   
85.
This study investigated that dieckol (DKL), a natural drug, inhibits colon cancer cell proliferation and migration by inhibiting phosphoinositide-3-kinase (PI3K), protein kinase B (AKT), and mammalian target of rapamycin (mTOR) phosphorylation in HCT-116 cells. The cells were treated with DKL in various concentrations (32 and 50 μM) for 24 h and then analyzed for various experiments. MTT (tetrazolium bromide) and crystal violet assay investigated DKL-mediated cytotoxicity. Dichlorodihydrofluorescein diacetate staining was used to assess the reactive oxygen species (ROS) measurement, and apoptotic changes were studied by dual acridine orange and ethidium bromide staining. Protein expression of cell survival, cell cycle, proliferation, and apoptosis protein was evaluated by western blot analysis. Results indicated that DKL produces significant cytotoxicity in HCT-116, and the half-maximal inhibitory concentration was found to be 32 μM for 24-h incubation. Moreover, effective production of ROS and enhanced apoptotic signs were observed upon DKL treatment in HCT-116. DKL induces the expression of phosphorylated PI3K, AKT, and mToR-associated enhanced expression of cyclin-D1, proliferating cell nuclear antigen, cyclin-dependent kinase (CDK)-4, CDK-6, and Bcl-2 in HCT-116. In addition, proapoptotic proteins such as Bax, caspase-9, and caspase-3 were significantly enhanced by DKL treatment in HCT-116. Hence, DKL has been considered a chemotherapeutic drug by impeding the expression of PI3K-, AKT-, and mTOR-mediated inhibition of proliferation and cell cycle-regulating proteins.  相似文献   
86.
Microhabitat use by marsh-edge fishes in a Louisiana estuary   总被引:3,自引:0,他引:3  
Synopsis We used a drop sampler to characterize use of the marsh-edge ecotone by small fishes along two transects running inland from the Gulf of Mexico for ca. 25 km in Louisiana's Barataria-Caminada Bay System. Monthly sampling was stratified among upper, middle, and lower reaches and within reaches to characterize fish responses to salinity, depth, distance from shore, substrate, dissolved oxygen concentration, temperature, turbidity, velocity, and emergent stem density. In 681 quantitative samples, covering 658 m2, collected between October 1987 and October 1989, we collected 57 fish species and 16 864 individuals, primarily larvae and juveniles. The 15 most abundant fishes, comprising 97.7% of all individuals, were concentrated near the marsh edge (i.e., 0 to 1.25 m distance). Some significant differences within species for seasonal variables (e.g., temperature and dissolved oxygen concentration) reflected the ephemeral duration of early life history stages. Other differences reflected ontogenetic microhabitat shifts (e.g., depth and distance from shore). Within ecological groups, characterized as demersal residents, nektonic transients, and demersal transients, spatial and temporal segregation reflected the particular habitat requirements of each species. In a principal component analysis of microhabitat use, the first three components were interpreted as seasonal, depth-and-distance, and salinity axes, respectively. The array of species and size classes in principal component space reflected the complex dimensionality of microhabitat use. The high density of fish larvae and juveniles near the marsh edge confirmed the importance of the marsh-edge ecotone as a nursery for many estuarine-dependent fishes.  相似文献   
87.
The permanent pancreas carcinoma cell line, PCI-24, was developed in order to analyse cytokine regulation on pancreas carcinoma and lymphokine-activated killer (LAK) cell interaction. PCI cells expressed ICAM-1 and HLA-ABC, but not HLA-DR antigens. PCI cells showed augmented ICAM-1 and HLA-ABC expression when incubated with interferon (IFN) and tumour necrosis factor . A similar but weak augmentary effect on the HLA-ABC and ICAM-1 surface expression was seen with interleukin-1 treatment. Natural attachment of LAK to PCI cells was augmented by recombinant IFN in close association with ICAM-1 up-regulation on PCI cells. In addition, natural attachment was significantly inhibited by anti-LFA-1 and anti-ICAM-1 antibody treatments. Cytotoxicity of the LAK cells against PCI cells was also significantly inhibited with the same treatment. Thus, the attachment of LAK cells to PCI cells through LFA-1/ICAM-1 molecules appeared to be essential for the cytotoxicity for PCI cells. Pretreatment of PCI cells, but not of LAK cells, with IFN or other cytokines resulted in a decrease of susceptibility for LAK cell cytotoxicity. The decreased susceptibility inversely correlated with HLA-ABC expression on the PCI cells. The collective evidence indicates that, although LAK cell attachment to pancreas carcinoma cells through the LFA-1/ICAM-1 molecule is augmented by IFN, IFN treatment of pancreas carcinoma cells reduces LAK cell cytotoxicity possibly through an increase in HLA-ABC or a regulation of molecules closely associated to HLA-ABC expression.  相似文献   
88.
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90.
Summary A human anaplastic thyroid cancer cell line K-119, derived from a 77-yr-old woman who had developed marked neutrophilia and underwent surgery for anaplastic thyroid cancer, has been established. The spindlelike and polygonal cells in shape are stably proliferating since the beginning of its culture 2 yr ago. The cells grow rapidly and the population doubling time is 26 h. The chromosomes show many abnormalities and many marker chromosomes have been observed. Heterotransplantation of the cells into nude mice has resulted in the formation of tumors that are histologically interpreted as anaplastic cancer. The most noteworthy characteristics of the cell line are the many Ki-67-positive cells (86.3%) and that the cell line spontaneously secretes granulocyte colony-stimulating factor (G-CSF) and releases increased amounts of G-CSF in response to the stimulation of tumor necrosis factor, interleukin 1α, and interleukin 1β. The conditioned medium obtained from K-119 cells contains an autocrine factor stimulating the proliferation of themselves.  相似文献   
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