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121.
B Yang  RL Yu  S Tuo  CW Tuo  QZ Liu  N Zhang  XC Lu  XH Chi  SB Lv  LL Cai 《PloS one》2012,7(7):e41467

Background

Human xenograft models, resulting from orthotopic transplantation (implantation into the anatomically correct site) of histologically intact tissue into animals, are important for investigating local tumor growth, vascular and lymphatic invasion at the primary tumor site and metastasis.

Methodology/Principal Findings

We used surgical orthotopic transplantation to establish a nude mouse model of primary hepatic lymphoma (PHL), HLBL-0102. We performed orthotopic transfer of the HLBL-0102 tumor for 42 generations and characterized the tumor cells. The maintenance of PHL characteristics were supported by immunohistochemical and cytogenetic analysis. We also report the antitumor effect of Cantide, an antisense phosphorothioate oligonucleotide against hTERT, on the growth of HLBL-0102 tumors. We showed a significant, dose-dependent inhibition of tumor weight and serum LDH activity in the orthotopically transplanted animals by Cantide. Importantly, survival was prolonged in Cantide-treated HLBL-0102 tumor-bearing mice when compared to mock-treated mice.

Conclusions/Significance

Our study provided the basis for the development of a clinical trial protocol to treat PHL.  相似文献   
122.
To evaluate the effectiveness and safety of autologous cytokine-induced killer (CIK) cells in elderly patients with diffuse large B-cell lymphoma. Peripheral blood mononuclear cells (PBMC) were isolated from nine elderly patients with diffuse large B-cell lymphoma. PBMCs were augmented by priming with interferon gamma (IFN-γ) followed by IL-2 and monoclonal antibody (mAb) against CD3. Autologous CIK cells (range 5 × 10(9)-1 × 10(10)) were then infused back to individual patients; infusion was repeated every 4 weeks for 32 weeks (eight cycles). Patients were assessed for changes in lymphocyte subgroup, tumor-related biological parameters, imaging characteristics, the condition of remission, quality of life (QOL), and survival. Prior to CIK infusion, two patients were in complete remission and seven patients were in partial remission. After autologous CIK cell transfusions, the proportion of CD3+, CD3+CD8+, and CD3+CD56+ cells were significantly increased compared with baseline (P < 0.05); whereas serum levels of β2-microglobulin and LDH were significantly decreased (P < 0.05). The lymphoma symptoms were reduced and QOL was improved (P < 0.05) in all patients. All patients achieved complete remission at study endpoint. No adverse reactions were reported. Autologous CIK cell immunotherapy is safe and efficacious for the treatment of elderly patients with diffuse large B-cell lymphoma.  相似文献   
123.
Evergreen plants need to store reserves to allow for their survival during the winter months and for new leaf growth in the following spring. In many of the tree species, these reserve functions are mainly carried out by starch, which is degraded to soluble carbohydrates during the dormant season to maintain active respiration and provide protection against freezing. In the present study, two evergreen woody plants, S. przewalskii Kom. (SP) and S. chinensis (Lin.) Ant.(SC), were used to investigate the patterns of seasonal variation in the concentrations of soluble sugars, sucrose, fructose and starch, and the activities of sucrose-phosphate synthase (SPS), sucrose synthase (SUSY), neutral invertase (NI) and soluble acid invertase (SAI). Foliar soluble sugar, sucrose, fructose, and starch concentrations were markedly higher in SC than in SP; moreover, the activities of SPS, SUSY, NI and SAI were also higher in SC than in SP. There were generally higher concentrations of soluble sugars, sucrose and fructose and SPS activities in the winter than in the summer for both Sabina trees, which was consistent with the necessity for protection against freezing; however, opposite results were found with regards to starch concentrations and the activities of SUSY, NI and SAI. In contrast with the activities of SUSY, NI and SAI, the negative correlation observed between SPS and air temperature was likely a reflection of its crucial role in the acquisition of freezing tolerance by sucrose metabolism in the winter. These results suggest that higher carbon reserves do not give S. chinensis (Lin.) Ant. a competitive advantage in tolerating cold temperatures and that only SPS, but not SUSY, NI and SAI, may play a positive role in freezing tolerance by increasing soluble sugar.  相似文献   
124.
Genetic polymorphisms in human genes can influence the risk for HIV-1 infection and disease progression, although the reported effects of these alleles have been inconsistent. This review highlights the recent discoveries on global and Chinese genetic polymorphisms and their association with HIV-1 transmission and disease progression.  相似文献   
125.
Genetic polymorphisms in human genes can influence the risk for HIV-1 infection and disease progression, although the reported effects of these alleles have been inconsistent. This review highlights the recent discoveries on global and Chinese genetic polymorphisms and their association with HIV-1 transmission and disease progression.  相似文献   
126.
稳定干扰素的-α-2b多糖玻璃体颗粒的研究   总被引:1,自引:1,他引:0  
目的:在温和条件下,将结构脆弱的干扰素-α-2b制备成可耐受苛刻制荆条件的微粒.方法:通过干扰素在多糖和PEG共溶液中的冷冻相分离作用,制备干扰素分配在多糖分散相的微粒.在显微镜和扫描电镜下观察了颗粒的大小和外观,同时将颗粒置于不同密度的溶剂中考察了密度.用MicroBCA和ELISA法测量了颗粒的包封率和载药量;用SEC-HPLC和细胞病变抑制法初步考察了颗粒制备后蛋白稳定性的变化.结果:颗粒表面光滑圆整,粒径约1~5μm,密度约为1.47~1.48 g/cm3,说明颗粒结构致密.MicroBCA和ELISA法测量的包封率分别为90%和80%以上,SEC-HPLC法测定蛋白无明显聚集体产生,细胞病变抑制法得出的活性保留率80%左右.结论:冷冻相分离法是一种简单但有效的制备蛋白多糖颗粒的方法.颗粒粒径均一,形态规整.该方法可进一步应用于蛋白缓释及微粉吸入等剂型的研究.  相似文献   
127.
Accumulating evidence demonstrates that hypoxia‐inducible factor (HIF‐α) hydroxylase system has a critical role in vascular remodelling. Using an endothelial‐specific prolyl hydroxylase domain protein‐2 (PHD2) knockout (PHD2ECKO) mouse model, this study investigates the regulatory role of endothelial HIF‐α hydroxylase system in the development of renal fibrosis. Knockout of PHD2 in EC up‐regulated the expression of HIF‐1α and HIF‐2α, resulting in a significant decline of renal function as evidenced by elevated levels of serum creatinine. Deletion of PHD2 increased the expression of Notch3 and transforming growth factor (TGF‐β1) in EC, thus further causing glomerular arteriolar remodelling with an increased pericyte and pericyte coverage. This was accompanied by a significant elevation of renal resistive index (RI). Moreover, knockout of PHD2 in EC up‐regulated the expression of fibroblast‐specific protein‐1 (FSP‐1) and increased interstitial fibrosis in the kidney. These alterations were strongly associated with up‐regulation of Notch3 and TGF‐β1. We concluded that the expression of PHD2 in endothelial cells plays a critical role in renal fibrosis and vascular remodelling in adult mice. Furthermore, these changes were strongly associated with up‐regulation of Notch3/TGF‐β1 signalling and excessive pericyte coverage.  相似文献   
128.
刘拓 《人类学学报》2017,36(1):49-61
伊朗作为亚洲大陆腹地沟通东西方的大国,对探究旧石器时代早期东亚和西方石器工业面貌的差异,是重要的地理节点。然而伊朗旧石器的材料相对匮乏,外人知之甚少。为方便理解,本文首先介绍了伊朗的自然与政区地理概况,梳理了伊朗一百多年旧石器考察、发掘和研究的时间脉络,在此基础上,对其旧石器时代早期文化的发现与研究现状予以整理。伊朗旧石器的研究程度目前尚低,不宜过早做出结论;从现有证据看,伊朗西部受一定程度的阿舍利传统影响,而东部几乎不见;最后从传播路径的角度,推测了伊朗及周边地区在旧石器时代早期可能的文化图景。  相似文献   
129.
目的:观察不同浓度的枸杞多糖(LBP)对HepG2细胞胰岛素抵抗的影响并探讨其机制。方法:采用高糖高胰岛素处理HepG2细胞24 h建立胰岛素抵抗细胞模型后,用台盼蓝检测活力大于95%的HepG2细胞,以104/孔密度接种于96孔板内,细胞贴壁后以30 μg/ml、100 μg/ml、300 μg/ml的LBP培养48 h,200 μl/well,各组均设4个复孔。检测不同浓度的LBP对HepG2细胞活性及胰岛素抵抗的影响;细胞内丙二醛(MDA)含量和超氧化物歧化酶(SOD)的活性;各组细胞胰岛素信号转导通路中相关蛋白(IRS-2、PI3-K、Akt、GLUT2)的表达。结果:MTT显示:与正常对照组相比,IR模型组MDA含量显著升高,SOD活力明显降低,同时IRS-2、PI-3K、Akt、GLUT2蛋白表达水平明显下降;与IR模型组相比,中、高浓度LBP组MDA的含量明显降低,SOD的活力显著升高,且IRS-2、PI-3K、Akt、GLUT2蛋白表达水平明显升高;在相同的时间内,随着LBP浓度的增加,OD值逐渐降低;在同一浓度干预下,随着时间的延长,OD值也逐渐降低;葡萄糖消耗实验表明中、高浓度的LBP可显著提高胰岛素抵抗HepG2细胞的葡萄糖消耗量,而低浓度LBP对HepG2细胞葡萄糖消耗量无明显影响。结论:中、高浓度枸杞多糖能改善HepG2细胞胰岛素抵抗,其作用机制可能与降低细胞氧化应激水平及提高胰岛素信号传导通路相关蛋白表达有关。  相似文献   
130.
Site-specific determination of molecular motion and water accessibility by indirect detection of 2H NMR spectra has advantages over dipolar-coupling based techniques due to the large quadrupolar couplings and the ensuing high angular resolution. Recently, a Rotor Echo Short Pulse IRrAdiaTION mediated cross polarization (RESPIRATIONCP) technique was developed, which allowed efficient transfer of 2H magnetization to 13C at moderate 2H radiofrequency field strengths available on most commercial MAS probes. In this work, we investigate the 2H–13C magnetization transfer characteristics of one-bond perdeuterated CD n spin systems and two-bond H/D exchanged C–(O)–D and C–(N)–D spin systems in carbohydrates and proteins. Our results show that multi-bond, broadband 2H–13C polarization transfer can be achieved using 2H radiofrequency fields of ~50 kHz, relatively short contact times of 1.3–1.7 ms, and with sufficiently high sensitivity to enable 2D 2H–13C correlation experiments with undistorted 2H spectra in the indirect dimension. To demonstrate the utility of this 2H–13C technique for studying molecular motion, we show 2H–13C correlation spectra of perdeuterated bacterial cellulose, whose surface glucan chains exhibit a motionally averaged C6 2H quadrupolar coupling that indicates fast trans-gauche isomerization about the C5–C6 bond. In comparison, the interior chains in the microfibril core are fully immobilized. Application of the 2H–13C correlation experiment to H/D exchanged Arabidopsis primary cell walls show that the O–D quadrupolar spectra of the highest polysaccharide peaks can be fit to a two-component model, in which 74% of the spectral intensity, assigned to cellulose, has a near-rigid-limit coupling, while 26% of the intensity, assigned to matrix polysaccharides, has a weakened coupling of 50 kHz. The latter O–D quadrupolar order parameter of 0.22 is significantly smaller than previously reported C–D dipolar order parameters of 0.46–0.55 for pectins, suggesting that additional motions exist at the C–O bonds in the wall polysaccharides. 2H–13C polarization transfer profiles are also compared between statistically deuterated and H/D exchanged GB1.  相似文献   
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