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1.
The effect of granular coral limestone and Leca as adsorbents for removing Acid Cyanine 5R (AC5R) from aqueous solution was studied. The optimum pH and adsorbent particles size in both adsorbents were determined to be 3 and 297 μm, respectively. The optimum dosages of coral limestone and granular Leca were 0.150 and 0.145 g/mg of dye, respectively. Also, results have shown that the adsorption efficiency by both coral limestone and Leca increased with the decreasing adsorbent particles size. Moreover, under similar conditions, the maximum removal efficiency by granular coral limestone and Leca was 94% and 88%, respectively. The results revealed that the performance of granular coral limestone was better in AC5R removal than that of Leca granulated under such condition. In total, granular coral limestone and Leca act as suitable adsorbents for removing dye pollutants from an aqueous solution.  相似文献   
2.
Drug delivery to the brain for the treatment of pathologies with a CNS component is a significant clinical challenge. P‐glycoprotein (PgP), a drug efflux pump in the endothelial cell membrane, is a major factor in preventing therapeutics from crossing the blood‐brain barrier (BBB). Identifying PgP regulatory mechanisms is key to developing agents to modulate PgP activity. Previously, we found that PgP trafficking was altered concomitant with increased PgP activity and disassembly of high molecular weight PgP‐containing complexes during acute peripheral inflammatory pain. These data suggest that PgP activity is post‐translationally regulated at the BBB. The goal of the current study was to identify proteins that co‐localize with PgP in rat brain microvessel endothelial cell membrane microdomains and use the data to suggest potential regulatory mechanisms. Using new density gradients of microvessel homogenates, we identified two unique pools (1,2) of PgP in membrane fractions. Caveolar constituents, caveolin1, cavin1, and cavin2, co‐localized with PgP in these fractions indicating the two pools contained caveolae. A chaperone (Hsc71), protein disulfide isomerase and endosomal/lysosomal sorting proteins (Rab5, Rab11a) also co‐fractionated with PgP in the gradients. These data suggest signaling pathways with a potential role in post‐translational regulation of PgP activity at the BBB.

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3.
Higher cognitive performance, maintenance of mental health and psychological well-being require adequate prefrontal cortex (PFC) function. “Inverted U-shaped” dopamine model indicates optimal PFC dopamine level is important to attain its function while high or low levels have adverse effects. Catechol-O-methyltransferase (COMT) and methylenetetrahydrofolate reductase (MTHFR) may be involved in this complex non-linear PFC dopamine regulation. We addressed whether genetic variation reflecting COMT and MTHFR activities can explain the inter-individual mental health differences in healthy Japanese men (n = 188). The mental health was measured by Mental Health Inventory (MHI)-5 score. The rs4633–rs4818–rs4680 haplotypes were used to represent the multilevel COMT activities, while for MTHFR, the functional single polymorphism, rs1801133 (C677T), was used. We examined the effectiveness of haplotype-based association analysis of COMT on mental health together with studying its interaction with MTHFR-C677T. As a result, the relation between activity-ranked COMT genotype and MHI-5 score showed a tendency to fit into an “inverted U-shaped” quadratic curve (P = 0.054). This curvilinear correlation was significant in the subjects with MTHFR-CC (P < 0.001), but not with MTHFR T-allele carriers (P = 0.793). Our pilot study implies a potential influence of COMT and MTHFR genotypic combination on normal variation of mental health.  相似文献   
4.
A novel cloning vector that can be used to identify recombinant Escherichia coli colonies by activation of the green fluorescent protein gene (GFP) was constructed. Screening using the vector does not require special reagents. The recombinant plasmid activates GFP, and the rate of false-positive results is low.  相似文献   
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Sine oculis homeobox homolog 1 (SIX1) has been supposed to be correlated with the metastasis and poor prognosis of several malignancies. However, the effect of SIX1 on the metastatic phenotype of tumor cells and the underlying mechanisms were still unclear to date. Here we report that SIX1 can promote α5β1-mediated metastatic capability of cervical cancer cells. SIX1 promoted the expression of α5β1 integrin to enhance the adhesion capacity of tumor cells in vitro and tumor cell arrest in circulation in vivo. Moreover, higher expression of SIX1 in tumor cells resulted in the increased production of active MMP-2 and MMP-9, up-regulation of anti-apoptotic genes (BCL-XL and BCL2) and down-regulation of pro-apoptotic genes (BIM and BAX), thus promoting the invasive migration and anoikis-resistance of tumor cells. Importantly, blocking α5β1 abrogated the regulatory effect of SIX1 on the expression of these genes, and also abolished the promotional effect of SIX1 on invasive capability of tumor cells. Furthermore, knock-down of α5 could abolish the promoting effect of SIX1 on the development of metastatic lesions in both experimental and spontaneous metastasis model. Therefore, by up-regulating α5β1 expression, SIX1 not only promoted the adhesion capacity, but also augmented ECM-α5β1-mediated regulation of gene expression to enhance the metastatic potential of cervical cancer cells. These results suggest that SIX1/α5β1 might be considered as valuable marker for metastatic potential of cervical cancer cells, or a therapeutic target in cervical cancer treatment.  相似文献   
7.
目的:研究扶正化积方对H22荷瘤小鼠化疗的增效减毒作用。方法:建立小鼠皮下H22移植性肝癌模型,随机分为4组:模型对照组、FZHJF组(40.95g/kg)、5-氟尿嘧啶组(5-FU)(0.2 m L/10g)和联合给药组(FZHJF+5-FU),连续给药12 d后,采集肿瘤与脏器称重并计算抑瘤率、肝脏指数、脾脏指数和胸腺指数;并对各组肿瘤外观和肿瘤病理进行分析。结果:肿瘤病理结果显示均为典型的肝细胞癌。与模型对照组比较,其余三组瘤重均显著减小(P0.05);而联合用药组的瘤重显著小于5-FU组和FZHJF组(P0.05),肿瘤外观图也显示联合给药组瘤块小于FZHJF组和5-FU组。扶正化积方单独使用的抑瘤率为40.5%,联合5-FU后,抑瘤率达到66.7%,大于两者合并用药后的理论相加效应值65.6%;与5-FU组比较,FZHJF组与联合用药组的体质量显著增加(P0.05),FZHJF组与联合用药组的胸腺指数与脾脏指数均显著高于模型对照组和5-FU组(P0.05)。结论:扶正化积方对H22肝癌荷瘤小鼠的化疗具有增效和减毒双重作用。  相似文献   
8.
目的:探讨肠内营养支持对克罗恩病营养障碍患者血清IGF-I、IGF-IR及IGFBP-5水平的影响。方法:选取我院收治的克罗恩病患者92例,根据治疗方法不同分为对照组及治疗组,每组各46例。对照组予以美沙拉嗪和醋酸泼尼松龙片常规治疗,治疗组在对照组基础上加用肠内营养混悬液静脉滴注。观察并比较两组患者治疗前后血清中IGF-I、IGF-IR及IGFBP-5水平的变化情况。结果:与治疗前比较,两组患者治疗后血清IGF-I、IGF-IR及IGFBP-5水平明显降低,差异具有统计学意义(P0.05);与对照组比较,治疗组患者治疗后血清IGF-I、IGF-IR及IGFBP-5水平明显降低,差异具有统计学意义(P0.05);与对照组比较,治疗组患者治疗后的营养状况明显改善,临床总有效率明显提高,差异具有统计学意义(P0.05)。结论:肠内营养支持能够降低克罗恩病营养障碍患者血清中IGF-I、IGF-IR及IGFBP-5水平,改善肠纤维化和营养状态,提高临床疗效。  相似文献   
9.
目的:研究去甲基化药物5-氮杂胞嘧啶核苷(5-Azacytidine,5-Aza-C)对鼻咽癌细胞端粒长度及细胞生长增殖的影响。方法: 常规培养鼻咽癌CNE,CNE1,CNE2 及5-8F细胞系,5-Aza-C 处理鼻咽癌细胞后,甲基化测序聚合酶链反应(MSP)法检测亚端粒 区D4Z4 甲基化,端粒限制性片断检测端粒长度,CCK-8 检测细胞增殖。结果:2.5 uM浓度的5-Aza-C处理后,亚端粒区D4Z4 序 列的甲基化水平明显下降,约在15-20%之间,与处理前的甲基化水平(35-48%)有明显差异,差异均有统计学意义(P < 0.05)。在1 uM和2.5 uM浓度的5-Aza-C 处理后,四种细胞的端粒长度明显缩短,长度在2-4.5kb 之间,差异具有统计学意义(P < 0.05)。5uM 的5-Aza-C处理72 h 后,CNE,CNE1,CNE2 和5-8F 的生存率分别为51.27%,50.46%,48.85%,48.83%,10 uM 的5-azaC 处理72 h 后,CNE,CNE1,CNE2 和5-8F的生存率分别为31.64%,32.34%,30.01%,32.10%,与对照组比较差异有统计学意义(P<0.01)。结 论:5-Aza-C 能缩短端粒长度,抑制鼻咽癌细胞生长增殖活性。  相似文献   
10.
目的:探讨人Daintain 基因5''调控区的序列特征。方法:利用在线软件BLAST、Neural Network Promoter Prediction、Promoter 2.0、Promoter SCAN、EMBOSS、CpG Island Searcher 和TF SEARCH预测人Daintain 基因启动子区域、CpG 岛分布和转录因子结 合位点。结果:人Daintain 基因5''调控区存在1 个CAAT盒。Daintain 基因可能存在6 个启动子位点,CpG岛可能位于216 bp 区 间( 23 ~ 238 bp)。评分85 分以上时,该序列存在251 个可能的转录因子结合位点;评分90 分以上时,该序列存在70 个可能的转 录因子结合位点;评分95 分以上时,该序列存在16个可能的转录因子结合位点;评分100 分以上时,该序列存在7 个可能的转 录因子结合位点;这些结合的转录因子基本是与免疫细胞增殖或性别发生有关。结论:人Daintain 基因5''调控区的生物信息学研 究表明其转录受甲基化和多种转录因子的调控,为研究Daintain 基因启动子的功能提供理论基础。  相似文献   
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