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1.
J Gastroenterol Hepatol ; 31(4): 795-801, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26513524

ABSTRACT

BACKGROUND AND AIM: The vitamin D receptor (VDR) regulates immune responses and inflammation through binding with 1,25-dihydroxyvitamin D, the active form of vitamin D. The serum 25-hydroxyvitamin D (25(OH)D) level clinically reflects vitamin D status in the human body. We investigated the association of VDR polymorphisms and 25(OH)D levels in Chinese patients with Crohn's disease (CD). METHODS: Vitamin D receptor polymorphisms (FokI, BsmI, ApaI, and TaqI) were genotyped by SNaPshot. Serum 25(OH)D levels were measured by electro-chemiluminescence immunoassay. RESULTS: A total of 297 patients with CD and 446 controls were recruited. Compared with controls, mutant alleles and genotypes of BsmI and TaqI were less prevalent in patients with CD (all P < 0.05/4 = 0.0125). The AAC haplotype formed by BsmI, ApaI, and TaqI was also less prevalent in patients with CD (P = 0.004). Furthermore, 124 patients and 188 controls were randomly selected for measurements of 25(OH)D levels. Average 25(OH)D level was lower in patients with CD than in controls (15.46 ± 8.11 vs 21.64 ± 9.45 ng/mL, P < 0.001) and negatively linked to CD activity index (ß = -0.829, P < 0.001), platelet count (ß = -0.253, P < 0.001) and neutrophil percentage (ß = -0.136, P = 0.005) in patients with CD. The ApaI mutant genotype and vitamin D deficiency (<20 ng/mL) were independently associated with CD (P = 0.009, P < 0.001, respectively). In patients with CD, vitamin D deficiency interacted with FokI, ApaI, and TaqI mutant genotypes (P = 0.027, P = 0.024, and P = 0.040, respectively). CONCLUSIONS: Vitamin D receptor (BsmI, ApaI, and TaqI) mutations and lower 25(OH)D levels are associated with CD in Chinese patients. Moreover, VDR (FokI, ApaI, and TaqI) mutations and vitamin D deficiency may have a combined impact on CD.


Subject(s)
Asian People/genetics , Crohn Disease/blood , Crohn Disease/genetics , Genetic Association Studies , Polymorphism, Genetic , Receptors, Calcitriol/genetics , Vitamin D/analogs & derivatives , Adult , Crohn Disease/etiology , Female , Humans , Male , Mutation , Vitamin D/blood , Vitamin D Deficiency/complications , Young Adult
2.
J Recept Signal Transduct Res ; 35(6): 530-5, 2015.
Article in English | MEDLINE | ID: mdl-25347331

ABSTRACT

The association studies from different ethnic groups showed that vitamin D receptor (VDR) gene polymorphisms might be connected with the susceptibility to ulcerative colitis (UC); however, the conclusions were less consistent. Our study aimed to analyze the associations of UC with common mutations of VDR in Chinese patients. A total of 382 UC patients and 489 healthy controls were recruited. The genotypes of VDR FokI (rs2228570), BsmI (rs1544410), ApaI (rs7975232) and TaqI (rs731236) were examined by SNaPshot assays. Haplotype analysis was performed in all study subjects. After Bonferroni correction, the mutant alleles and genotypes of VDR FokI, BsmI, ApaI and TaqI did not statistically differ between UC patients and the controls (all p > 0.0125). However, the mutant allele C and genotype TC + CC of FokI gene were significantly increased in patients with mild and moderate UC compared to those with severe UC (C allele: 54.1% versus 39.3%, OR = 1.83, 95% CI: 1.21-2.75, p = 0.004; TC + CC genotype: 81.6% versus 57.1%, OR = 3.32, 95% CI: 1.83-6.06, p < 0.001, respectively). Haplotype analysis showed that the VDR BsmI, ApaI and TaqI polymorphic loci were in a strong linkage disequilibrium. Furthermore, the frequency of AAC haplotype was statistically lower in UC patients than that in the controls (3.8 versus 5.9%, OR = 0.63, 95% CI: 0.39-1.01, p = 0.039). In conclusion, the mutation of FokI gene influenced severity of the disease in UC patients. Moreover, the AAC haplotype formed by the VDR BsmI, ApaI and TaqI gene might engender a reduced risk of UC attack.


Subject(s)
Colitis, Ulcerative/genetics , Polymorphism, Single Nucleotide/genetics , Receptors, Calcitriol/genetics , Case-Control Studies , China/epidemiology , Colitis, Ulcerative/epidemiology , Colitis, Ulcerative/pathology , Female , Genetic Predisposition to Disease , Genotype , Humans , Male , Middle Aged , Prognosis , Risk Factors
3.
Opt Lett ; 39(10): 3034-7, 2014 May 15.
Article in English | MEDLINE | ID: mdl-24978266

ABSTRACT

In this study, the degree of conversion (DC) of an acrylic-based resin (IP-L 780) in two-photon polymerization (TPP) is systematically investigated via Raman microspectroscopy. A quantitative relationship between TPP laser parameters and the DC of the resin is established. Nonlinear increase in DC with increased laser average power is observed. The resin DC is more sensitive to the laser average power than the laser writing speed. Nanoindentation was employed to correlate the results obtained from Raman microspectroscopy with the mechanical properties of microstructures fabricated by TPP. At constant writing speeds, microstructures fabricated with high laser average powers possess high hardness and high reduced Young's modulus (RYM), indicating high DCs. The results are in line with high DCs measured under the same TPP parameters in Raman microspectroscopy. Raman microspectroscopy is proved to be an effective, rapid, and nondestructive method characterizing microstructures fabrication by TPP.

4.
J Gastroenterol Hepatol ; 29(10): 1778-85, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24720527

ABSTRACT

BACKGROUND AND AIM: FUT2 and FUT3 genes are responsible for the formation of histo-blood group antigens, which act as binding sites for some intestinal microbes. Several studies suggested that FUT2 gene might affect the intestinal microbiota composition and modulate innate immune responses. However, the effect of FUT2 polymorphisms on Crohn's disease (CD) is uncertain. Our study aimed to analyze associations of CD with FUT2 and FUT3 polymorphisms in Chinese population. METHODS: A total of 273 CD patients and 479 controls were recruited. The genotypes of FUT2 (rs281377, rs1047781, and rs601338) and FUT3 (rs28362459, rs3745635, and rs3894326) were detected by SNaPshot analysis. RESULTS: Compared with controls, homozygote TT of FUT2 (rs1047781) was significantly increased in CD patients (TT vs others; P = 0.002, odds ratio [OR] = 1.767, 95% confidence interval [CI] = 1.235-2.528). The haplotype TT formed with FUT2 (rs281377) and (rs1047781) was more prevalent in CD patients than in controls (48.9% vs 43.5%, P = 0.046). Mutant T allele and homozygote TT of FUT2 (rs1047781) were increased in colonic CD patients compared with controls (P < 0.001, OR = 1.843, 95% CI = 1.353-2.512; P < 0.001, OR = 2.607, 95% CI = 1.622-4.191, respectively). Although allele and genotypic distributions of FUT3 were not statistically different between CD patients and controls, mutant allele and genotype of FUT3 (rs28362459) and (rs3745635) were significantly discrepant in three subgroups of CD patients according to lesion locations (all P < 0.05). CONCLUSIONS: Our study strongly implicates the polymorphic locus of FUT2 (rs1047781) in CD susceptibility in Chinese population. Mutations of FUT3 (rs28362459) and (rs3745635) might influence the lesion locations in CD patients.


Subject(s)
Crohn Disease/genetics , Fucosyltransferases/genetics , Mutation/genetics , Polymorphism, Genetic/genetics , Adult , Asian People , Female , Humans , Male , Middle Aged , Young Adult , Galactoside 2-alpha-L-fucosyltransferase
5.
Clin Res Hepatol Gastroenterol ; 41(1): 110-117, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27771345

ABSTRACT

There is now growing evidence suggesting that Vitamin D is playing a critical role in modulating the innate and adaptive immune responses. Several polymorphisms have been identified in the vitamin D receptor (VDR) gene but their association with ulcerative colitis (UC) susceptibility remained controversy. In the current study, we examined the association between VDR polymorphisms and serum level of 25-hydroxyvitamin D [25(OH)D] with UC in Chinese Han population. Polymorphisms of FokI (rs2228570)/BsmI (rs1544410)/ApaI (rs7975232)/TaqI (rs731236) in the VDR gene were assessed in a case-control study comprising 404 UC patients and 612 controls. Moreover, 25(OH)D levels were measured by electro-chemiluminescence immunoassay in 75 UC patients and 120 controls. Our results suggested that BsmI polymorphism frequency was significantly lower in UC patients (P=0.028), and the frequency of AAC haplotype formed by BsmI, ApaI and TaqI was also significantly lower in UC patients (P=0.012). Moreover, FokI polymorphism was more frequently observed in patients with mild and moderate UC as compared to those with severe UC (P=0.001, P<0.001, respectively). Average 25(OH)D level was lower in UC patients than in controls (19.3±6.8 vs. 21.8±7.3ng/mL, P=0.017), and was significantly correlated with hemoglobin (ß=0.49, P<0.001), C-reactive protein (ß=-0.36, P<0.001), severity of UC (ß=-0.21, P=0.025) and FokI polymorphism (ß=-0.20, P=0.031) in UC patients. Interestingly, there was a significant correlation between FokI polymorphism and vitamin D deficiency (<20ng/mL) in UC patients (P=0.006). Together, these results supported that VDR polymorphisms and 25(OH)D level were significantly correlated with UC risk and severity in Chinese Han population.


Subject(s)
Colitis, Ulcerative/genetics , Polymorphism, Single Nucleotide/genetics , Receptors, Calcitriol/genetics , Vitamin D/analogs & derivatives , Adult , Alleles , Asian People/statistics & numerical data , Case-Control Studies , China/epidemiology , Colitis, Ulcerative/ethnology , Female , Genotype , Humans , Male , Middle Aged , Vitamin D/blood , Vitamin D/genetics
6.
Adv Mater ; 28(10): 2002-9, 2016 03 09.
Article in English | MEDLINE | ID: mdl-26754028

ABSTRACT

Laser-directed assembly of multiwalled carbon nanotubes (MWNTs) in 3D space is investigated via a two-photon polymerization technique. MWNT-thiol-acrylate (MTA) composite resins are developed with high MWNT concentrations up to 0.2 wt%, over one order of magnitude higher than previously published work. Significantly enhanced electrical and mechanical properties of the 3D micro-/nanostructures are achieved. Microelectronic devices made of the MTA resins are demonstrated.

7.
Sci Rep ; 4: 4892, 2014 May 08.
Article in English | MEDLINE | ID: mdl-24809639

ABSTRACT

To unleash the full potential of graphene in electronics and optoelectronics, high-quality graphene patterns on insulating substrates are required. However, existing methods generally follow a "synthesis + patterning" strategy, which are time consuming and costly for fabricating high-quality graphene patterns on desired substrates. We developed a nanofabrication process to deposit high-quality graphene patterns directly on insulating substrates via a solid-phase laser direct writing (LDW) process. Open-air and room-temperature fabrication of graphene patterns on insulating substrates has been achieved via a femtosecond LDW process without graphene transfer and patterning. Various graphene patterns, including texts, spirals, line arrays, and integrated circuit patterns, with a feature line width of 800 nm and a low sheet resistance of 205 ohm/sq, were fabricated. The LDW method provides a facile and cost-effective way to fabricate complex and high-quality graphene patterns directly on target substrates, which opens a door for fabricating various advanced functional devices.

8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 21(6): 1429-34, 2013 Dec.
Article in Zh | MEDLINE | ID: mdl-24370024

ABSTRACT

This study was aimed to analyze the expression of NKG2D ligands in human leukemic cells and to investigate the effects of matrine on NKG2D ligand expression. The expressions of NKG2D ligand MICA/B, ULBP1-3 in several human leukemia cell lines (K562, OUN-1, U937 and K562/AO2), as well as primary leukemic cells isolated from malignant leukemia patients were analyzed by flow cytometry. After treatment with different doses of matrine, the expression level of NKG2D ligands in these leukemic cells was detected by FCM. The results indicated that NKG2D ligand expression was detected in both the leukemia cell lines and primary malignant leukemic cells. Generally, the expression of ULBP was high or obviously higher than that of MICA/B in leukemia cell lines and primary leukemic cells. The expression pattern of NKG2D ligands was different among these cells, possibly due to the different types of leukemia. Not all the expression of NKG2D ligands was upregulated after matrine treatment. Much higher expressions of ULBP2 and ULBP3 were found in K562 cells, compared to the other cell lines, which partly contributes to the higher sensitivity of K562 cells to NK cytotoxicity as target cells. It is concluded that there is universal expression of NKG2D ligand in leukemia cells. The high ULBP expression is prevalent in human leukemia cells. Matrine has the potential to induce the expression of NKG2D ligands in leukemia cells.


Subject(s)
Alkaloids/pharmacology , Intercellular Signaling Peptides and Proteins/metabolism , NK Cell Lectin-Like Receptor Subfamily K/metabolism , Quinolizines/pharmacology , Cell Line, Tumor , GPI-Linked Proteins/metabolism , Gene Expression Regulation, Leukemic , Histocompatibility Antigens Class I/metabolism , Humans , K562 Cells , Tumor Cells, Cultured , Matrines
9.
Adv Mater ; 25(4): 630-4, 2013 Jan 25.
Article in English | MEDLINE | ID: mdl-23136061

ABSTRACT

The direct formation of graphene on various dielectric surfaces is successful via a single-step rapid thermal processing (RTP) of substrates coated with amorphous carbon (C) and nickel (Ni) thin films. High-quality graphene is obtained uniformly on the whole surface of wafers with a controlled number of graphene layers. The monolayer graphene exhibits a low sheet resistance and a high optical transmittance in the visible range.

10.
Leuk Lymphoma ; 51(7): 1326-36, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20497005

ABSTRACT

Signal transducer and activator of transcription 3 (STAT3), a transcription factor, is constitutively activated in various types of cancers. Previous investigations have demonstrated that this overexpression of STAT3 in human malignancies plays important roles in maintaining the characteristics of malignant tumors by having an effect on proliferation, differentiation, and/or immortalization. Thus, inhibition of STAT3 expression could be a potent therapeutic approach in cancer treatment. In this study, we introduced STAT3 siRNA into the human chronic myelogenous leukemia (CML) K562 cell line, which has constitutive activation of STAT3, to elucidate the role of STAT3 in CML. The cells were transducted with STAT3 siRNA using lentivirus. FACS, real-time PCR, and Western blot were used to study changes in STAT3 expression levels in transducted cells by comparing with negative control siRNA lentivirus transduction. Knockdown of STAT3 by STAT3 siRNA caused a decrease in STAT3 protein level, inhibition of growth and proliferation, cell cycle blockade, visible morphologic changes, and induction of apoptosis in K562 cells. These findings demonstrate that STAT3 does indeed play a critical role in the survival of K562 cells, which may have potential application in designing molecular therapies for CML treatment.


Subject(s)
Apoptosis , Cell Proliferation , Gene Silencing , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , STAT3 Transcription Factor/genetics , Blotting, Western , Cell Cycle , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction , STAT3 Transcription Factor/antagonists & inhibitors , STAT3 Transcription Factor/metabolism , Tumor Cells, Cultured
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