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1.  Association between CYP1B1 Gene Polymorphisms and Risk Factors and Susceptibility to Laryngeal Cancer 
The aim of this study was to investigate the association between polymorphism of the cytochrome P450 1B1 (CYP1B1) gene, a metabolic enzyme gene, and the susceptibility to laryngeal cancer among the Chinese Han population.
In a case-control study, we investigated polymorphisms in the CYP1B1 gene (rs10012, rs1056827, and rs1056836) with a real-time quantitative polymerase chain reaction (PCR) assay (TaqMan). The study was conducted with 300 Chinese Han patients with laryngeal cancer and 300 healthy Chinese Han subjects in a control group. We also studied the interactions between genetic polymorphism and risk factors such as smoking and alcohol consumption in the pathogenesis of laryngeal cancer.
There were statistically significant differences in the distributions of the rs1056827 and rs1056836 genotypes between the 2 groups. Regarding rs1056827, carriers of the T allele had a significantly higher risk of laryngeal cancer than the G-allele carriers (OR=1.4339, 95% CI: 1.1268–1.8247; P=0.0034). The difference was still statistically significant after adjusting for factors such as age, sex, smoking, and drinking (adjusted OR=1.743, 95% CI: 1.124–3.743, P<0.001). However, regarding rs1056836, the G allele carriers had a significantly lower risk of laryngeal cancer than the C allele carriers (OR=0.5557, 95% CI: 0.3787–0.8154; P=0.0027). The difference was statistically significant even after adjusting for factors such as age, sex, smoking, and drinking (adjusted OR=0.5641, 95% CI: 0.3212–0.8121, P=0.001). Subjects who carry the C-T-C haplotype have a significantly increased incidence of laryngeal cancer. We also found that CYP1B1 rs1056827 polymorphism had synergistic effects with smoking or alcohol consumption regarding the risk of laryngeal cancer.
CYP1B1 gene polymorphism is closely related to the onset of laryngeal cancer. There is a mutually synergistic effect between smoking, alcohol consumption, and CYP1B1 gene polymorphisms regarding laryngeal cancer.
PMCID: PMC4307736  PMID: 25619313
Laryngeal Neoplasms; Polymorphism, Single Nucleotide; Steroid 11-beta-Hydroxylase
2.  Relationship Between Amounts of Daily Cigarette Consumption and Abdominal Obesity Moderated by CYP2A6 Genotypes in Chinese Male Current Smokers 
Cigarette smoking is an important risk factor for abdominal obesity. However, the degree to which the CYP2A6 genotype moderates the relationship between smoking and abdominal obesity has not been established.
This study aims to investigate whether or not the relationship between smoking quantity and abdominal obesity is influenced by CYP2A6 genotypes.
Nine hundred fifty-four male current smokers were selected. A venous specimen was collected to test serum cotinine and CYP2A6 genotype, and all smokers were divided into heavy (>15 cigarettes/day) and light smokers (≤15 cigarettes/day).
Heavy smoking increased the risk of abdominal obesity (odds ratio (OR)=1.57; 95% CI, 1.13–2.19) compared with light smoking. Furthermore, heavy smoking had a positive interactive effect with CYP2A6 poor metabolizer genotype on abdominal obesity (OR=3.90; 95% CI, 1.25– 12.18). Moreover, CYP2A6 poor metabolizer genotypes were associated with slower nicotine metabolism.
Heavy smoking may increase the risk of abdominal obesity—particularly in smokers with CYP2A6 poor metabolizer genotypes.
PMCID: PMC4114962  PMID: 22160797
Cigarette smoking; CYP2A6 genotypes; Abdominal obesity; Interaction
3.  Interaction between heavy smoking and CYP2A6 genotypes on type 2 diabetes and its possible pathways 
To explore the interactions between smoking and CYP2A6 genotypes on type 2 diabetes (T2DM) as well as potential pathways for smoking in causing T2DM.
Cross-sectional study.
A total of 1344 smokers with complete data from a community-based T2DM survey in Guangzhou and Zhuhai of China from July 2006 to June 2007 were interviewed with a structured questionnaire about socio-demographic status and daily cigarette consumption. Serum glucose, insulin, and cotinine were measured after an overnight fast. Subjects were genotyped for CYP2A6 and classified, according to genotype, into normal, intermediate, slow, or poor nicotine metabolizers based on prior knowledge of CYP2A6 allele associations with nicotine C-oxidation rate. Abdominal obesity was defined as a waist-to-hip ratio ≥0.90 for males or ≥0.85 for females. Type 2 diabetic patients (n=154) were diagnosed according to WHO 1999 criteria. Chi-square tests, multivariate logistic regression models, and a structural equation model were used in this study.
Multivariate analysis indicated that, compared with light smoking, heavy smoking significantly increased the risk of T2DM (odds ratio (OR)=1.75, 95% CI=1.01–3.05). There were significant interactions between heavy smoking and slow CYP2A6 (OR=5.12, 95% CI=1.08–24.23) and poor CYP2A6 metabolizer genotypes (OR=8.54, 95% CI=1.28–57.02) on T2DM. Structural equation modeling indicated that CYP2A6 moderation of smoking quantity risk on T2DM was mediated by the effects on serum cotinine, abdominal obesity, insulin resistance, and insulin secretion.
Heavy smoking was significantly associated with T2DM, and this association was moderated by CYP2A6 genotype and mediated by serum cotinine, abdominal obesity, insulin resistance, and insulin secretion.
PMCID: PMC4112659  PMID: 21964962
4.  Growth of Millimeter-Size Single Crystal Graphene on Cu Foils by Circumfluence Chemical Vapor Deposition 
Scientific Reports  2014;4:4537.
A simply and reproducible way is proposed to significantly suppress the nucleation density of graphene on the copper foil during the chemical vapor deposition process. By inserting a copper foil into a tube with one close end, the nucleation density on the copper foils can be reduced by more than five orders of magnitude and an ultra-low nucleation density of ~10 nucleus/cm2 has been achieved. The structural analyses demonstrate that single crystal monolayer graphene with a lateral size of 1.9 mm can be grown on the copper foils under the optimized growth condition. The electrical transport studies show that the mobility of such single crystal graphene is around 2400 cm2/Vs.
PMCID: PMC3971397  PMID: 24686949
5.  Associations of CYP2A6 genotype with smoking behaviors in southern China 
Addiction (Abingdon, England)  2011;106(5):985-994.
To investigate the association of CYP2A6 genetic polymorphisms with smoking-related phenotypes in Chinese smokers.
Case-only genetic association study.
Southern China
A total of 1,328 Han Chinese smokers who participated in a community-based chronic disease screening project in Guangzhou and Zhuhai from 2006 to 2007.
All participants were answered a structured questionnaire about socio-demographic status and smoking behaviors and informative alleles for the cytochrome P450 2A6 (CYP2A6) gene (CYP2A6 *4, *5, *7, *9 and *10) were genotyped.
The frequencies of CYP2A6 *4, *5, *7, *9 and *10 alleles were 8.5%, 1.2%, 6.3%, 13.5% and 2.4%, which corresponded to 48.9%, 15.4%, 24.2% and 11.5% of participants being classified as normal, intermediate, slow and poor metabolizers, respectively. Multivariate analyses demonstrated that compared with normal metabolizers, poor metabolizers reported smoking fewer cigarettes per day (adjusted OR = 0.49; 95% CI: 0.32–0.76), started smoking regularly later in life (adjusted OR = 1.55; 95% CI: 1.06–2.26) and, amongst former smokers, reported smoking for a shorter duration prior to quitting (adjusted OR = 0.33; 95% CI: 0.12–0.94). However, poor metabolizers were less likely to quit smoking and remain abstinent than normal metabolizers (OR = 0.54; 95% CI: 0.34–0.86).
Reduced metabolism function of CYP2A6 in smokers appears to be associated with fewer cigarettes smoked, later initiation of smoking regularly, shorter smoking duration and lower likelihood of smoking cessation.
PMCID: PMC3074015  PMID: 21205058
CYP2A6; genetic polymorphisms; smoking behavior; Chinese smokers
6.  High-throughput ballistic injection nanorheology to measure cell mechanics 
Nature protocols  2012;7(1):155-170.
High-throughput ballistic injection nanorheology is a method for the quantitative study of cell mechanics. Cell mechanics are measured by ballistic injection of submicron particles into the cytoplasm of living cells and tracking the spontaneous displacement of the particles at high spatial resolution. The trajectories of the cytoplasm-embedded particles are transformed into mean-squared displacements, which are subsequently transformed into frequency-dependent viscoelastic moduli and time-dependent creep compliance of the cytoplasm. This method allows for the study of a wide range of cellular conditions, including cells inside a 3D matrix, cell subjected to shear flows and biochemical stimuli, and cells in a live animal. Ballistic injection lasts < 1 min and is followed by overnight incubation. Multiple particle tracking for one cell lasts < 1 min. Forty cells can be examined in < 1 h.
PMCID: PMC4332792  PMID: 22222790
7.  Inflammation and Mechanical Stretch Promote Aortic Stiffening in Hypertension Through Activation of p38 MAP Kinase 
Circulation research  2013;114(4):616-625.
Aortic stiffening commonly occurs in hypertension and further elevates systolic pressure. Hypertension is also associated with vascular inflammation and increased mechanical stretch. The interplay between inflammation, mechanical stretch and aortic stiffening in hypertension remains undefined.
To determine the role of inflammation and mechanical stretch in aortic stiffening.
Methods and Results
Chronic angiotensin II infusion caused marked aortic adventitial collagen deposition, as quantified by Masson’s Trichrome Blue staining and biochemically by hydroxyproline content, in wild-type (WT) but not in Recombination Activation Gene-1 deficient (RAG-1−/−) mice. Aortic compliance, defined by ex-vivo measurements of stress-strain curves, was reduced by chronic angiotensin II infusion in WT mice (p<0.01) but not in RAG-1−/− mice (p<0.05). Adoptive transfer of T cells to RAG-1−/− mice restored aortic collagen deposition and stiffness to values observed in WT mice. Mice lacking the T cell derived cytokine IL-17a were also protected against aortic stiffening. In additional studies, we found that blood pressure normalization by treatment with hydralazine and hydrochlorothiazide prevented angiotensin II-induced vascular T cell infiltration, aortic stiffening and collagen deposition. Finally, we found that mechanical stretch induces expression of collagen 1α1, 3α1 and 5a1 in cultured aortic fibroblasts in a p38 MAP kinase-dependent fashion, and that inhibition of p38 prevented angiotensin II-induced aortic stiffening in vivo. IL-17a also induced collagen 3a1 expression via activation of p38 MAP kinase.
Our data define a pathway in which inflammation and mechanical stretch lead to vascular inflammation that promotes collagen deposition. The resultant increase in aortic stiffness likely further worsens systolic hypertension and its attendant end-organ damage.
PMCID: PMC4186716  PMID: 24347665
Inflammation; mechanical stretch; collagen deposition; aortic stiffening; vascular remodeling
8.  The pattern of DNA cleavage intensity around indels 
Scientific Reports  2015;5:8333.
Indels (insertions and deletions) are the second most common form of genetic variations in the eukaryotic genomes and are responsible for a multitude of genetic diseases. Despite its significance, detailed molecular mechanisms for indel generation are still unclear. Here we examined 2,656,597 small human and mouse germline indels, 16,742 human somatic indels, 10,599 large human insertions, and 5,822 large chimpanzee insertions and systematically analyzed the patterns of DNA cleavage intensities in the 200 base pair regions surrounding these indels. Our results show that DNA cleavage intensities close to the start and end points of indels are significantly lower than other regions, for both small human germline and somatic indels and also for mouse small indels. Compared to small indels, the patterns of DNA cleavage intensity around large indels are more complex, and there are two low intensity regions near each end of the indels that are approximately 13 bp apart from each other. Detailed analyses of a subset of indels show that there is slight difference in cleavage intensity distribution between insertion indels and deletion indels that could be contributed by their respective enrichment of different repetitive elements. These results will provide new insight into indel generation mechanisms.
PMCID: PMC4321175  PMID: 25660536
9.  Differential regulation of protein expression in response to polyunsaturated fatty acids in the liver of apoE-knockout mice and in HepG2 cells 
Polyunsaturated fatty acids (PUFAs) are nutrients necessary for life. The liver is the essential metabolic center, which aids in maintaining health via diverse biological actions. In the present work, a proteomics study was conducted with an aim to provide new insights into PUFA-regulated hepatic protein expression in apoE-knockout mice. Additionally, we investigated how n-3 PUFAs influence cytokine-challenge by using HepG2 cells as a model.
Through the proteomic analysis using 2-dimensional electrophoresis and mass spectrometry, we found that 28, 23, 14, and 28 hepatic proteins were up-regulated at least a two-fold difference in intensity compared with the control group in mice treated with the docosahexaenoic acid, eicosapentaenoic acid, arachidonic acid, and linoleic acid, respectively. In contrast, 12 hepatic proteins were down-regulated with a ratio value of less than 0.5 compared to their control counterparts by these four fatty acids. All of the altered proteins were then sorted according to their biochemical properties related to metabolism, redox stress/inflammation, enzymatic reactions, and miscellaneous functions. The results provide evidence that PUFAs may act as either pro-inflammatory or anti-inflammatory agents. Cytokine-challenged HepG2 cells were used to reveal the anti-inflammatory function of n-3 PUFAs. The results showed that interleukin (IL)-1β combined with IL-6 induced C-reactive protein (CRP) mRNA expression and its protein secretion by HepG2 cells. The CRP promoter activity was significantly increased in the IL-6-treated cells, whereas IL-1β alone had no effect. However, IL-1β and IL-6 acted synergistically to further enhance CRP promoter activities. Furthermore, n-3 PUFAs inhibited nuclear factor-κB (NF-κB) activation and the phosphorylation of the nuclear signal transducer and activator of transcription 3 (STAT3) during cytokine-induced CRP production.
This study indicates that PUFAs induced changes in the hepatic protein profile in vivo. Furthermore, n-3 PUFAs exert their anti-inflammatory properties through differential molecular mechanisms in hepatic cells. These results provide novel information regarding the roles of PUFAs in the liver at the tissue and cellular levels.
PMCID: PMC4331445
Polyunsaturated fatty acids (PUFAs); Proteomics; Inflammation; C-reactive protein (CRP); Nuclear factor-κB (NF-κB) pathway
13.  Promiscuous Rearrangements of the MYC Locus Hijack Enhancers and Super-Enhancers to Dysregulate MYC Expression in Multiple Myeloma 
Leukemia  2014;28(8):1725-1735.
MYC locus rearrangements – often complex combinations of translocations, insertions, deletions, and inversions - in multiple myeloma (MM) were thought to be a late progression event, which often did not involve immunoglobulin genes. Yet germinal center activation of MYC expression has been reported to cause progression to MM in an MGUS prone mouse strain. Although previously detected in 16% of MM, we find MYC rearrangements in nearly 50% of MM, including smoldering MM, and they are heterogeneous in some cases. Rearrangements reposition MYC near a limited number of genes associated with conventional enhancers, but mostly with super-enhancers (e.g., IGH, IGL, IGK, NSMCE2, TXNDC5, FAM46C, FOXO3, IGJ, PRDM1). MYC rearrangements are associated with a significant increase of MYC expression that is monoallelic, but MM tumors lacking a rearrangement have bi-allelic MYC expression at significantly higher levels than in MGUS. We also show that germinal center activation of MYC does not cause MM in a mouse strain that rarely develops spontaneous MGUS. It appears that increased MYC expression at the MGUS/MM transition usually is bi-allelic, but sometimes can be mono-allelic if there is a MYC rearrangement. Our data suggests that MYC rearrangements, regardless of when they occur during MM pathogenesis, provide one event that contributes to tumor autonomy.
PMCID: PMC4126852  PMID: 24518206
Monoclonal Gammopathy of Undetermined Significance; Multiple Myeloma; Genes, MYC; Enhancer and Super-Enhancer Elements, Genetic; Translocation, Genetic; Mice, Transgenic
14.  Using Current Data to Define New Approach in Age Related Macular Degeneration: Need to Accelerate Translational Research 
Current Genomics  2014;15(4):266-277.
Age related macular degeneration (AMD) is one of the major retinal degenerative disease of ageing whose complex genetic basis remains undeciphered. The involvement of various other factors like mitochondrial genes, cytoskeletal proteins and the role of epigenetics has been described in this review. Several population based AMD genetic studies have been carried out worldwide. Despite the increased publication of reports, clinical translation still eludes this davastating disease. We suggest models to address roadblocks in clinical translation hoping that these would be beneficial to drive AMD research towards innovative biomarkers and therapeutics Therefore, addressing the need large autopsy studies and combining it with efficient use of bioinformatic tools, statistical modeling and probing SNP-biomarker association are key to time bound resolution of this disease.
PMCID: PMC4133950  PMID: 25132797
Age related macular degeneration; Mitochondrial genes; Epigenetics; SNP; Biomarkers; Translational research; Bio-informatics.
15.  Functional Study of -724I/D Polymorphism in Apolipoprotein M (apoM) Gene Promoter Region and its Association with Myocardial Infarction 
The aim of this study was to detect the function of -724I/D polymorphism in the apolipoprotein M (apoM) gene promoter region and to determine its relationship with myocardial infarction (MI).
We selected 309 patients with MI and 309 healthy controls for this case-control study. The PCR products of the apoM gene promoter region were directly sequenced to analyze the -724I/D polymorphism. Differences in frequency distributions of genotype and allele were compared between the MI group and the control group. We used gene recombination and site-directed mutagenesis technique to observe the impact of -724 I/D on transcription activity of apoM gene promoter in vitro.
The allele frequency of the -724Del in the MI group was higher than that in the control group (9.5% vs. 3.2%, OR=3.156, 95% CI (1.876~5.309), P<0.001). Compared to the I/I genotype carriers, the apoM levels decreased but the total cholesterol (TC) levels increased significantly in the -724Del allele carriers in plasma. The activity of apoM I/I genotype promoter decreased significantly after the deletion mutation at -724 position in apoM gene.
-724 I/D polymorphism decreases the apoM promoter activity, down-regulates the apoM protein expression level, and increases the risk of MI.
PMCID: PMC4321410  PMID: 25637426
Amplified Fragment Length Polymorphism Analysis; Apoprotein(a); Coronary Artery Disease
16.  Synergistic antitumor interactions between MK-1775 and panobinostat in preclinical models of pancreatic cancer 
Cancer letters  2014;356(2 0 0):656-668.
Pancreatic cancer remains a clinical challenge, thus new therapies are urgently needed. The selective Wee1 inhibitor MK-1775 has demonstrated promising results when combined with DNA damaging agents, and more recently with CHK1 inhibitors in various malignancies. We have previously demonstrated that treatment with the pan-histone deacetylase inhibitor panobinostat (LBH589) can cause down-regulation of CHK1. Accordingly, we investigated using panobinostat to down-regulate CHK1 in combination with MK-1775 to enhance cell death in preclinical pancreatic cancer models. We demonstrate that MK-1775 treatment results in increased H2AX phosphorylation, indicating increased DNA double-strand breaks, and activation of CHK1, which are both dependent on CDK activity. Combination of MK-1775 and panobinostat resulted in synergistic antitumor activity in six pancreatic cancer cell lines. Finally, our in vivo study using a pancreatic xenograft model reveals promising cooperative antitumor activity between MK-1775 and panobinostat. Our study provides compelling evidence that the combination of MK-1775 and panobinostat has antitumor activity in preclinical models of pancreatic cancer and supports the clinical development of panobinostat in combination with MK-1775 for the treatment of this deadly disease.
PMCID: PMC4282784  PMID: 25458954
MK-1775; Panobinostat; Pancreatic cancer; CHK1; Drug combination
17.  Prognostic implications of estrogen receptor 1 and vascular endothelial growth factor A expression in primary gallbladder carcinoma 
AIM: To investigate the prognostic significance of estrogen receptor 1 (ER1) and vascular endothelial growth factor A (VEGF-A) expression in primary gallbladder carcinoma (GBC) to identify new prognostic markers for this malignancy.
METHODS: Using immunohistochemistry, we investigated ER1 and VEGF-A expression in 78 GBC and 78 cholelithiasis (CS) tissues. The results were correlated with clinicopathological features. Univariate and multivariate analyses were performed to evaluate the relationship between ER1 and VEGF-A expression and patients’ prognosis. Further Kaplan-Meier survival analysis was also performed.
RESULTS: ER1 and VEGF-A expression was significantly higher in GBC compared with CS (47/78 vs 28/78, P < 0.05; 51/78 vs 33/78, P < 0.05). ER1 expression was correlated with gender (P < 0.05) and VEGF-A expression was correlated with tumor differentiation in GBC patients (P < 0.05). In univariate analysis, age and tumor node metastasis (TNM) stage were factors associated with GBC prognosis (P < 0.05). Although there was no statistical difference between the expression of ER1 or VEGF-A and overall survival, the high expression of ER1 combined with VEGF-A predicted a poor prognosis for GBC patients (16.30 ± 1.87 vs 24.97 ± 2.09, log-rank P < 0.05). In multivariate analysis, combined expression of ER1 and VEGF-A and TNM stage were independent prognostic factors for GBC patients (P < 0.05).
CONCLUSION: Combined expression of ER1 and VEGF-A is a potential prognostic marker for GBC patients. Clinical detection of ER1 and VEGF-A in surgically resected GBC tissues would provide an important reference for decision-making of postoperative treatment programs.
PMCID: PMC4306169  PMID: 25632198
Gallbladder carcinoma; Estrogen receptor 1; Vascular endothelial growth factor A
18.  Relationship between Personality Disorder Functioning Styles and the Emotional States in Bipolar I and II Disorders 
PLoS ONE  2015;10(1):e0117353.
Bipolar disorder types I (BD I) and II (BD II) behave differently in clinical manifestations, normal personality traits, responses to pharmacotherapies, biochemical backgrounds and neuroimaging activations. How the varied emotional states of BD I and II are related to the comorbid personality disorders remains to be settled.
We therefore administered the Plutchick – van Praag Depression Inventory (PVP), the Mood Disorder Questionnaire (MDQ), the Hypomanic Checklist-32 (HCL-32), and the Parker Personality Measure (PERM) in 37 patients with BD I, 34 BD II, and in 76 healthy volunteers.
Compared to the healthy volunteers, patients with BD I and II scored higher on some PERM styles, PVP, MDQ and HCL-32 scales. In BD I, the PERM Borderline style predicted the PVP scale; and Antisocial predicted HCL-32. In BD II, Borderline, Dependant, Paranoid (-) and Schizoid (-) predicted PVP; Borderline predicted MDQ; Passive-Aggressive and Schizoid (-) predicted HCL-32. In controls, Borderline and Narcissistic (-) predicted PVP; Borderline and Dependant (-) predicted MDQ.
Besides confirming the different predictability of the 11 functioning styles of personality disorder to BD I and II, we found that the prediction was more common in BD II, which might underlie its higher risk of suicide and poorer treatment outcome.
PMCID: PMC4307975  PMID: 25625553
19.  Nucleophilic substitution-cyclization based fluorescent probes for hydrogen sulfide detection and bioimaging 
The design, synthesis, properties, and cell imaging applications of a series of pyridine-disulfide based fluorescent probes (WSP1, WSP2, WSP3, WSP4 and WSP5) for hydrogen sulfide detection are reported. The strategy is based on the dual-nucleophilicity of hydrogen sulfide. A hydrogen sulfide mediated tandem nucleophilic substitution-cyclization reaction is used to release the fluorophores and turn on the fluorescence. The probes showed high sensitivity and selectivity for hydrogen sulfide over other reactive sulfur species including cysteine and glutathione.
PMCID: PMC4049170  PMID: 24339269
fluorescent probes; hydrogen sulfide; cell imaging; cyclization; fluorescence
20.  Bio-functionalized dense-silica nanoparticles for MR/NIRF imaging of CD146 in gastric cancer 
Nano dense-silica (dSiO2) has many advantages such as adjustable core–shell structure, multiple drug delivery, and controllable release behavior. Improving the gastric tumor-specific targeting efficiency based on the development of various strategies is crucial for anti-cancer drug delivery systems.
Superparamagnetic iron oxide nanoparticles (SPION) were coated with dSiO2 as core–shell nanoparticles, and labeled with near infra-red fluorescence (NIRF) dye 800ZW (excitation wavelength: 778 nm/emission wavelength: 806 nm) and anti-CD146 monoclonal antibody YY146 for magnetic resonance (MR)/NIRF imaging study in xenograft gastric cancer model. The morphology and the size of pre- and postlabeling SPION@dSiO2 core–shell nanoparticles were characterized using transmission electron microscopy. Iron content in SPION@dSiO2 nanoparticles was measured by inductively coupled plasma optical emission spectrometry. Fluorescence microscopy and fluorescence-activated cell sorter studies were carried out to confirm the binding specificity of YY146 and 800ZW–SPION@dSiO2–YY146 on MKN45 cells. In vivo and in vitro NIRF imaging, control (nanoparticles only) and blocking studies, and histology were executed on MKN45 tumor-bearing nude mice to estimate the affinity of 800ZW–SPION@dSiO2–YY146 to target tumor CD146.
800ZW–SPION@dSiO2–YY146 nanoparticles were uniformly spherical in shape and dispersed evenly in a cell culture medium. The diameter of the nanoparticle was 20–30 nm with 15 nm SPION core and ~10 nm SiO2 shell, and the final concentration was 1.7 nmol/mL. Transverse relaxivity of SPION@dSiO2 dispersed in water was measured to be 110.57 mM−1·s−1. Fluorescence activated cell sorter analysis of the nanoparticles in MKN45 cells showed 14-fold binding of 800ZW–SPION@dSiO2–YY146 more than the control group 800ZW–SPION@dSiO2. Series of NIRF imaging post intravenous injection of 800ZW–SPION@dSiO2–YY146 demonstrated that the MKN45 xenograft tumor model could be clearly identified as early as a time point of 30 minutes postinjection. Quantitative analysis revealed that the tumor uptake peaked at 24 hours postinjection.
This is the first successful study of functional nanoparticles for MR/NIRF imaging of cell surface glycoprotein CD146 in gastric cancer model. Our results suggest that 800ZW–SPION@dSiO2–YY146 nanoparticles will be applicable in tumor for image-guided therapy/surgery.
PMCID: PMC4309778  PMID: 25653520
SPION; nanotechnology; EMT; SPION@dSiO2; xenograft; gastric cancer
21.  Education influences the association between genetic variants and refractive error: a meta-analysis of five Singapore studies 
Human Molecular Genetics  2013;23(2):546-554.
Refractive error is a complex ocular trait governed by both genetic and environmental factors and possibly their interplay. Thus far, data on the interaction between genetic variants and environmental risk factors for refractive errors are largely lacking. By using findings from recent genome-wide association studies, we investigated whether the main environmental factor, education, modifies the effect of 40 single nucleotide polymorphisms on refractive error among 8461 adults from five studies including ethnic Chinese, Malay and Indian residents of Singapore. Three genetic loci SHISA6-DNAH9, GJD2 and ZMAT4-SFRP1 exhibited a strong association with myopic refractive error in individuals with higher secondary or university education (SHISA6-DNAH9: rs2969180 A allele, β = −0.33 D, P = 3.6 × 10–6; GJD2: rs524952 A allele, β = −0.31 D, P = 1.68 × 10−5; ZMAT4-SFRP1: rs2137277 A allele, β = −0.47 D, P = 1.68 × 10−4), whereas the association at these loci was non-significant or of borderline significance in those with lower secondary education or below (P for interaction: 3.82 × 10−3–4.78 × 10−4). The evidence for interaction was strengthened when combining the genetic effects of these three loci (P for interaction = 4.40 × 10−8), and significant interactions with education were also observed for axial length and myopia. Our study shows that low level of education may attenuate the effect of risk alleles on myopia. These findings further underline the role of gene–environment interactions in the pathophysiology of myopia.
PMCID: PMC3869359  PMID: 24014484
22.  Carbamidocyclophanes F and G with Anti-Mycobacterium tuberculosis Activity from the Cultured Freshwater Cyanobacterium Nostoc sp. 
Tetrahedron letters  2014;55(3):686-689.
Two new (1 and 2) and three known (3–5) carbamidocyclophanes were isolated from a cultured freshwater cyanobacterium Nostoc sp. (UIC 10274) obtained from a sample collected at Des Plaines, Illinois. Their planar structures and stereoconfigurations were determined by extensive spectroscopic analysis including 1D/2D NMR experiments, HRESIMS as well as CD spectroscopy. Carbamidocyclophane F (1) showed potent anti-Mycobacterium tuberculosis activity in the microplate Alamar blue assay and low-oxygen-recovery assay with MIC values of 0.8 and 5.4 µM, respectively. Carbamidocyclophane F (1) also displayed antimicrobial activities against the gram positive bacteria Staphylococcus aureus and Enterococcus faecalis with MIC values of 0.1 and 0.2 µM, respectively. Carbamidocyclophane F (1) and Carbamidocyclophane G (2) both showed antiproliferative activity against MDA-MB-435 and HT-29 human cancer cell lines with IC50 values in the range from 0.5 to 0.7 µM.
PMCID: PMC4161986  PMID: 25225453
Cyanobacteria; Nostoc sp.; [7.7]paracyclophane; Anti- Mycobacterium tuberculosis Activity
23.  Reconstruction and analysis of a genome-scale metabolic model of the oleaginous fungus Mortierella alpina 
Mortierella alpina is an oleaginous fungus used in the industrial scale production of arachidonic acid (ARA). In order to investigate the metabolic characteristics at a systems level and to explore potential strategies for enhanced lipid production, a genome-scale metabolic model of M. alpina was reconstructed.
This model included 1106 genes, 1854 reactions and 1732 metabolites. On minimal growth medium, 86 genes were identified as essential, whereas 49 essential genes were identified on yeast extract medium. A series of sequential desaturase and elongase catalysed steps are involved in the synthesis of polyunsaturated fatty acids (PUFAs) from acetyl-CoA precursors, with concomitant NADPH consumption, and these steps were investigated in this study. Oxygen is known to affect the degree of unsaturation of PUFAs, and robustness analysis determined that an oxygen uptake rate of 2.0 mmol gDW−1 h−1 was optimal for ARA accumulation. The flux of 53 reactions involving NADPH was significantly altered at different ARA levels. Of these, malic enzyme (ME) was confirmed as a key component in ARA production and NADPH generation. When using minimization of metabolic adjustment, a knock-out of ME led to a 38.28% decrease in ARA production.
The simulation results confirmed the model as a useful tool for future research on the metabolism of PUFAs.
Electronic supplementary material
The online version of this article (doi:10.1186/s12918-014-0137-8) contains supplementary material, which is available to authorized users.
PMCID: PMC4301621  PMID: 25582171
Mortierella alpina; Arachidonic acid; Genome-scale metabolic model; Polyunsaturated fatty acids; Malic enzyme
24.  Establishment and ultrasound characteristics of atherosclerosis in rhesus monkey 
BioMedical Engineering OnLine  2015;14(Suppl 1):S13.
Atherosclerosis is one of the main risk factors cause acute cerebral-cardio vascular diseases. It's of great significance to establish an atherosclerosis animal model that can mimic the characteristics and nature course of human patients. Therefore, a rhesus monkey model was induced by high-fat diet to monitor their lipid profile and intima-media thickness (IMT) of artery walls and study atherosclerosis progression.
Fifty male rhesus monkeys were enrolled in this study. All of these monkeys were aged 7 to 14 years with BMI >30 kg/m2. They were fed with high-fat diet containing 10% of fat for the first 48 weeks. Use ultrasound to measure the IMT at bilateral common carotid arteries and their bifurcations and aorta (AO) of the monkeys, and screen out the individuals with thickened IMT for the next phase. In the next 48 weeks, some of these monkeys (n = 4) were fed with standard diet containing 3% fat. Meanwhile the other monkeys (n = 5) were fed with high-fat diet for another 48 weeks. Their serum lipid level was monitored and arterial IMT was also determined periodically.
Serum lipid level of all 50 monkeys elevated after fed with high-fat diet for the first 48 weeks. IMT thickening at right common carotid bifurcation and aorta (AO) was thickened in 9 monkeys. Furthermore, 4 of these 9 monkeys were fed with standard diet and other 5 monkeys were fed with high-fat diet in the following 48 weeks. The serum lipid level of the 4 monkeys recovered and their IMT at RBIF and AO did not progress. However, the lipid level of other 5 monkeys remained high, and their IMT thickening of AO progressed, and plaques and calcification focuses were found at the anterior wall of aorta near the bifurcation of common iliac artery.
After high-fat diet induction for 96 weeks, serum lipid levels of rhesus monkeys elevated significantly, which subsequently caused IMT thickening and plaques formation. When IMT thickening occurred, further vascular injury may be prevented by reducing diet fat content. Our study indicates that vascular injury of high-fat diet induced rhesus monkey is similar to that of human in position and progression.
PMCID: PMC4306102  PMID: 25602196
25.  Clustering by neurocognition for fine-mapping of the schizophrenia susceptibility loci on chromosome 6p 
Genes, brain, and behavior  2009;8(8):785-794.
Chromosome 6p is one of the most commonly implicated regions in the genome-wide linkage scans of schizophrenia, whereas further association studies for markers in this region were inconsistent likely due to heterogeneity. This study aimed to identify more homogeneous subgroups of families for fine mapping on regions around markers D6S296 and D6S309 (both in 6p24.3) as well as D6S274 (in 6p22.3) by means of similarity in neurocognitive functioning. A total of 160 families of patients with schizophrenia comprising at least two affected siblings who had data for 8 neurocognitive test variables of the Continuous Performance Test (CPT) and the Wisconsin Card Sorting Test (WCST) were subjected to cluster analysis with data visualization using the test scores of both affected siblings. Family clusters derived were then used separately in family-based association tests for 64 single nucleotide polymorphisms covering the region of 6p24.3 and 6p22.3. Three clusters were derived from the family-based clustering, with deficit cluster 1 representing deficit on the CPT, deficit cluster 2 representing deficit on both the CPT and the WCST, and a third cluster of non-deficit. After adjustment using false discovery rate for multiple testing, SNP rs13873 and haplotype rs1225934-rs13873 on BMP6-TXNDC5 genes were significantly associated with schizophrenia for the deficit cluster 1 but not for the deficit cluster 2 or non-deficit cluster. Our results provide further evidence that the BMP6-TXNDC5 locus on 6p24.3 may play a role in the selective impairments on sustained attention of schizophrenia.
PMCID: PMC4286260  PMID: 19694819
endophenotype; sustained attention deficit; executive dysfunction; candidate gene; cluster analysis; schizophrenia

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