To obtain robust and thermo-stable enzyme aggregates,
p
-benzoquinone was used as cross-linker and bovine serum albumin (BSA) as crowding macromolecules to prepare cross-linked enzyme aggregates ...(CLEAs) of lipase. Effects of cross-linking time and cross-linker content on the activity, thermal stability and characteristics of enzyme aggregates were examined carefully. It was observed that when the content of
p
-benzoquinone was 5 mM and amount of BSA was 125% of that of lipase (w/w), the specific activity of cross-linked co-aggregates of lipase and BSA was 79.8 U mg
−1
, 2.44-fold of that of cross-linked enzyme aggregates of lipase without BSA. Moreover, after heat treatment for 96 h at 50 °C, the CLEAs prepared with this facile routine kept 75.18% of their initial activity, 5.01-fold more than that of the just CLEAs using glutaraldehyde. Furthermore, BSA macromolecules in lipase CLEAs enhanced the catalytic efficiency of free and just lipase CLEAs without BSA by 1.45 and 2.83 times, respectively. The proposed crosslinking technique would rank among the potential strategies for efficiently preparing robust and thermo-stable enzyme aggregates.
This paper reports an all-metal metasurface with reflection-type surface lattice resonance (SLR), which is more suitable for high-efficiency refractive index (RI) sensing than transmission-type SLR ...metasurfaces due to direct and strong light-matter interaction. The measured full width at half maximum (FWHM) of the SLR is 13.5 nm, keeping a balance between the noise immunity and sensing efficiency. Notably, the RI sensitivity is determined by the lattice period with regularity and controllability, which provides a theoretical guide to designing a sensor with a target sensitivity. Besides, the SLR phenomenon can also be realized by the different nanostructures and lattice arrays flexibly. This research can support diverse applications involving not only RI sensing but also nonlinear optics, nano-laser, etc.
AIM: NGX6, NAG-7 and BRD7 genes are tumor related genes, which have been newly cloned by positional candidate cloning strategy. This study was designed to investigate the expression levels of NGX6, ...NAG-7 and BRD7 genes in human gastric and colorectal cancer tissues, and their corresponding normal tissues, and to investigate whether these genes play a role in the pathogenesis of gastric and colorectal cancers.METHODS: Reverse transcription-polymerase chain reaction (RT-PCR), dot hybridization and Northem blot analysis were used to compare the expression levels of NGX6, NAG-7 and BRD7 genes in 34 gastric cancer tissues and 34 colorectal cancer tissues with their corresponding normal tissues of the same patients, respectively.RESULTS: Among the 34 colorectal cancer specimens and the 34 gastric cancer specimens, the expression of NGX6 in 25 colorectal cancer tissues was absent or very weak (73.5 %) by RT-PCR analysis. The down-regulation rate of NGX6 in colorectal cancer tissues was significantly higher than that in corresponding normal tissues (26.5 %,9/34)(P<0.005). Moreover, the down-regulation of NGX6 was significantly correlated with lymph node and/or distance metastases. Patients with lymph node and/or distance metastasis had much higher down-regulation rate of NGX6 than palJents without metastases (93.8 % vs55.6 %, P<0.05).However no correlation was found between the expression of NGX6 and pathologic type of colorectal cancer in this study, and also the expression of NGX6 did not display any difference between gastric cancer and corresponding normal tissues (58.8 % vs70.6 %, P>0.25). Dot hybridization and Northern blot analysis confirmed the results of RT-PCR.Furthermore, NAG-7 and BRD7 mRNA was not up- or down-regulated in gastric and colorectal cancers compared with their corresponding normal tissues in our study.CONCLUSION: The down-regula'don of NGX6 may be dosely associated with tumorigenesis and metastasis of colorectal cardnoma. However, it may not oontribute to the development and progression of gastric carcinoma. In addition, the expression levels of NAG-7, and BRD7 did not alber in gastric and colorectal cancers. This seems to suggest that NAG-7and BRD7 genes may not play a role in gastric and colorectal carcinogenesis.
AIM: NAG6 gene is a novel tumor related gene identified recently. This study was designed to examine the expression of this gene in gastric cancer and corresponding normal tissues, and to investigate ...its role in the occurrence and development of gastric cancer, also to study if the genetic structure of NAG6 was altered in gastric cancer.METHODS: Reverse transcription-polymerase chain reaction (RT-PCR), Northern blot analysis and dot hybridization were used to compare the expression level of NAG6 gene in 42 cases of gastric cancer tissues with their corresponding normal tissues of the same patients respectively. In addition,restriction fragment length polymorphism (RFLP) analysis was adopted to study if the genetic structure of NAG6 was altered in gastric carcinomas.RESULTS: The expression of NAG6 in 57.1% gastric cancer tissues (25/42) was absent by RT-PCR analysis. The down-regulation rate of NAG6 in gastric cancer tissues was significantly higher than that in corresponding normal tissues(P<0.01). However no correlation between the down-regulation of NAG6 and lymph-node and/or distance metastasis was found in this study (P>0.05). Dot hybridization confirmed the results of RT-PCR. Furthermore,the results of EcoRI RFLP analysis of NAG6 gene demonstrated that 3 of 7 cases of gastric cancer showed loss of 5 kb fragment in comparison with their corresponding normal tissues.CONCLUSION: NAG6 gene is significantly down regulated in gastric cancer. The loss of genetic materials may be the cause of down-regulation of NAG6 expression. This seems to suggest that NAG6 may represent a candidate of putative tumor suppressor gene at 7q31-32 loci associated with gastric carcinoma. The down-regulation of this gene may play a role in occurrence and development of this disease, however it may not be associated with lymph node and/or distance metastasis.
The Napster case has drawn enormous attention to digital intellectual property right problems of online file swapping. These peer-to-peer network technologies represent a powerful new paradigm for ...networking. In this paper, we try to figure out the intellectual property right problems of peer-to-peer network, in order to deal with potential digital piracy to avoid similar litigation. If libraries can embrace peer-to-peer technologies into their own services, they will possibly develop new service models, or improve existing ones.
AIM: To investigate the inhibitory effect of in vivoexpression of expressing plasmid pCH510 of recombinant fibronectin polypeptide (CH50) on hepatocellular carcinoma and the improved therapeutic ...effect of pCH510 in combination with chemotherapeutic agents and Hsp70-H22 hepatocarcinoma antigen peptide on tumor.METHODS: Mice were inoculated with H22 hepatccarcinoma cells. The chemotactic effect of the expression of plasmid pCH510 on immunocytes was observed after in vivo transfection, tissue slicing and HE staining. Inhibitory effect of transfection with pCH510 on routine tumor originatedfrom different inoculative doses was observed. The inhibitory effect of immediate transfection with pCH510 after chemotherapy on tumor was compared with that of transfection 5 days after chemotherapy. The change of function and amount of mouse peritoneal macrophages and the peripheral blood immunocytes resulted from administration of chemotherapeutic agents were detected. The peptides mixture was prepared from H22 hepatocarcinoma cells, pCH510 + Hsp70-H22 antigen peptides were injected into tumor-bearing mice with or without chemotherapy, to observe the inhibitory effects on tumor.RESULTS: At the tumor tissue site injected with pCH510,there were a great number of immunocytes which mainly were macrophages, lymphocytes and neutrophils.Transfection of plasmid pCH510 inhibited significantly the murine tumor induced by different inoculative doses. The inhibitory effect was negatively correlated with the inoculative dose. The therapeutic effect was not improved by immediate transfection with pCH510 after chemotherapy, but was significantly improved by transfection with pCH510 5 days after chemotherapy. Chemotherapeutic agent decreased the number of immunocytes and suppressed their activation in vivo. After injection of drug, the amount of immunocytes was the lowest from d 1 to d 3 and returned to normal level on the 10th day. Transfection with plasmid pCH510 alone could inhibit tumor induced by the inoculation with 10^4 H22 cells. The tumor originated from the inoculation with 10^5 H22 cells was inhibited by pCH510+Hsp70-H22 antigen peptides and that from the inoculation with 10^6 H22 cells was inhibited by pCH510+HspT0-H22 antigen peptides in combination with chemotherapeutic agents.CONCLUSION: In vivo expression of pCH510 recruits immune cells, inhibits tumor growth, and enhances the efficacy of chemotherapy, But the proper timing of combining chemotherapy with pCH510 must be taken into great account, The synergism of pCH510 and Hsp70-H22 peptides can improve the efficacy, which could be further enhanced if they are used following chemotherapy, Chemotherapeutic agent + pCH510 + Hsp70-H22 peptides is a promising therapeutic approach of combination treatment of tumor,
The Napster case has drawn enormous attention to digital intellectual property right problems of online file swapping. These peertopeer network technologies represent a powerful new paradigm for ...networking. In this paper, we try to figure out the intellectual property right problems of peertopeer network, in order to deal with potential digital piracy to avoid similar litigation. If libraries can embrace peertopeer technologies into their own services, they will possibly develop new service models, or improve existing ones.
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