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101.
Chung LC Tsui KH Feng TH Lee SL Chang PL Juang HH 《Molecular nutrition & food research》2011,55(11):1666-1676
Scope: Prostate‐specific antigen (PSA) is a well‐known marker for diagnosing and monitoring prostate cancer. Curcumin, a yellow curry pigment, has been reported to enhance androgen receptor (AR) degradation. We examined the effects of curcumin on increasing PSA expression by hypoxia and prolyl hydroxylase inhibitors, L ‐mimosine and dimethyloxalylglycine (DMOG), in human prostate carcinoma LNCaP cells. Methods and results: The 3H‐thymidine incorporation assay revealed that either L ‐mimosine or DMOG treatments attenuated cell proliferation. Immunoblot and enzyme‐linked immunosorbent assays (ELISA) indicated that both L ‐mimosine and DMOG have an effect similar to hypoxia, which stabilized hypoxia‐inducible factor‐1α (HIF‐1α) and induced PSA gene expression. The results of the immunoblot and transient gene expression assays indicated that induction of the PSA expression by hypoxia is both HIF‐1α‐ and AR‐dependent. Immunoblot assays revealed that a curcumin treatment (10 μM) decreased the protein abundance of AR but did not significantly affect the protein levels of HIF‐1α and vascular endothelial growth factor, which were induced by hypoxia. ELISA and transient gene expression assays indicated that curcumin blocked the activation of L ‐mimosine or DMOG treatment on PSA expression. Conclusions: These results indicate that curcumin blocked the enhanced effect of PSA expression by L ‐mimosine and DMOG that induce hypoxia condition. 相似文献
102.
In this paper, we study a versatile iterative framework for the reconstruction of uniform samples from nonuniform samples
of bandlimited signals. Assuming the input signal is slightly oversampled, we first show that its uniform and nonuniform samples
in the frequency band of interest can be expressed as a system of linear equations using fractional delay digital filters.
Then we develop an iterative framework, which enables the development and convergence analysis of efficient iterative reconstruction
algorithms. In particular, we study the Richardson iteration in detail to illustrate how the reconstruction problem can be
solved iteratively, and show that the iterative method can be efficiently implemented using Farrow-based variable digital
filters with few general-purpose multipliers. Under the proposed framework, we also present a completed and systematic convergence
analysis to determine the convergence conditions. Simulation results show that the iterative method converges more rapidly
and closer to the true solution (i.e. the uniform samples) than conventional iterative methods using truncation of sinc series. 相似文献
103.
Hing-Mo Lam Chi-Ying Tsui 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2007,54(7):591-595
In this brief, a new architecture for high-fan-in CMOS comparator is proposed. The architecture is based on a hierarchical two-stage comparator structure and a dynamic MUX is used instead of a comparator in the second stage of the structure. By doing so, the fast dynamic MUX significantly improves the overall delay of the high-fan-in comparators. At the same time, a novel high-performance static priority encoder is proposed to generate the control signal for the MUX. A 64-bit MUX-based comparator has been built and compared with the existing fastest single-cycle design in the study by Lam and Tsui (2006). From both the post-layout simulation and test-chip measurement results, it is shown that the performance is improved by around 28%. 相似文献
104.
105.
KH Yeh MT Lin DT Lin JL Tang LT Lui JF Lin YS Chang AL Cheng SC Yu KJ Chang YC Chen 《Canadian Metallurgical Quarterly》1998,49(3):237-244
BACKGROUND: Epidemiologic studies are necessary to determine the prevalence of allergic diseases. This varies widely depending on allergen preparations and patients studied. OBJECTIVE: To investigate the prevalence of atopic disease, skin test reactivity, total and specific IgE to common allergens, and other variables in a sample of students from Málaga, southern Spain. METHODS: Three hundred sixty-five students (age 17.9 +/- 1.18) were interviewed by an allergist. Skin prick tests were performed with Dermatophagoides pteronyssinus, Artemisia vulgaris, Plantago lanceolata, Chenopodium album, Olea europaea, Phleum pratense, Parietaria judaica, Cynodon dactylon, Alternaria tenuis, and cat dander. Total and specific IgE to D. pteronyssinus, Olea, and Parietaria were determined. RESULTS: Of all subjects studied, 19.9% suffered from rhinoconjunctivitis, 4.1% rhinoconjunctivitis plus asthma, 3.1% asthma alone, and 0.8% atopic dermatitis; 46.4% had a positive skin test to at least one allergen (28.2% to D. pteronyssinus, 20.4% to Olea, 13.8% to Phleum); and 43% had total IgE > 100 kU/L and 44.7% a family history of atopy. Allergic symptoms were strongly associated with skin test positivities and family allergic history. Patients with asthma or skin prick test positive had higher total IgE values than others (P < .01). There was a significant correlation between specific IgE values and wheal size in skin test. CONCLUSIONS: Our findings confirm the high prevalence of atopic diseases, and the close relationship of skin tests reactivity (or presence of specific IgE) to allergens with symptoms of asthma and rhinitis. The presence of a family history of allergic diseases influences the development of positive skin tests and atopic illness. Dermatophagoides pteronyssinus and pollen of Olea europaea were found to be the most common allergens. 相似文献
106.
The putative E1 of hepatitis C virus (HCV) was expressed in Escherichia coli using a glutathione-S-transferase (GST) fusion protein system. The full length E1 protein is difficult to express. A series of E1 DNA fragments was generated and used for expression vector construction. Fusion proteins containing the E1 C-terminal region could not be expressed. When this region was truncated, the fusion proteins were synthesized to high levels. The possibility of this C-terminal region hampering the production of fusion protein was further explored. A construct with this segment directly fused to the C-terminus of GST indeed generated no detectable recombinant protein. According to the predicted structure of E1, this region may have membrane-associating properties. The expression results suggest a general approach to facilitate the production of viral membrane proteins in prokaryotes. Furthermore, these recombinant E1 proteins generated as antigens were used for Western blotting with sera from HCV-infected individuals. It was found that E1 is antigenic during HCV natural infection. 相似文献
107.
108.
An extension of the high nitrogen partial pressure CW Co2 laser regime, which operates without auxiliary cooling, to the high-nitrogen high-helium partial pressure regime with an output power one order of magnitude greater is discussed. Both regimes rely on an unstable glow discharge plasma with extended electrodes that presents nonperiodic voltage spikes 相似文献
109.
TJ Yoon YC Yoo TB Kang YJ Baek CS Huh SK Song KH Lee I Azuma JB Kim 《Canadian Metallurgical Quarterly》1998,20(4-5):163-172
We here demonstrated the prophylactic effect of an extract (KM-110) from Viscum album coloratum, a Korean mistletoe, on tumor metastasis produced by highly metastatic tumor cells, colon 26-M3.1 carcinoma, B16-BL6 melanoma and L5178Y-ML25 lymphoma cells, using experimental models in mice. Intravenous (i.v.) administration of KM-110 (100 microg/mouse) 2 days before tumor inoculation significantly inhibited lung metastasis of B16-BL6 and colon 26-M3.1 cells, and liver and spleen metastasis of L5178Y-ML25 cells. The prophylactic effect of KM-110 on tumor metastasis was evident with various administration routes, i.e. subcutaneous, oral, intranasal as well as i.v., and was dependent upon the dose of KM-110 administered. Furthermore, mice given KM-110 (100 microg) 2 days before tumor inoculation showed significantly prolonged survival rates compared with the untreated mice. In a time course analysis of NK activity, i.v. administration of KM-110 (100 microg) significantly augmented NK cytotoxicity to Yac-a tumor cells from 1 to 3 days after KM-110 treatment. Furthermore, depletion NK cells by injection of rabbit anti-asialo GM1 serum completely abolished the inhibitory effect of KM-110 on lung metastasis of colon 26-M3.1 cells. These results suggest that KM-110 possesses immunopotentiating activity which enhances the host defense system against tumors, and that its prophylactic effect on tumor metastasis is mediated by NK cell activation. 相似文献
110.
The effects of glyceryl nonivamide (GLNVA) on ionic currents were compared and examined in rat pituitary GH3 cells. Hyperpolarization-activated K+ currents in GH3 cells bathed in high-K+ Ca2+-free external solution were studied to assess effects of GLNVA on the an inwardly rectifying K+ current (I(K(IR))). GLNVA is very potent in blocking I(K(IR)) in a concentration-dependent manner, with a half maximal concentrations of 0.1 microM. The complete block of I(K(IR)) achieved with concentrations > or = 1 microM revealed the presence of a non-inactivating current. We also found that GLNVA at a concentration above 30 microM inhibited L-type voltage-dependent Ca2+ current and two components of K+ outward currents, while GLNVA (< or = 3 microM) did not have any effect on them. This study shows that GLNVA, in addition to retaining the capability of eliciting peptidergic neurons, is a selective block of I(K(IR)) in GH3 cells and will provide a useful tool for characterizing I(K(IR)) and understanding its physiological function. In addition, the carefulness should be taken about the interpretation of GLNVA-mediated responses in vivo or in vitro. 相似文献