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1.  Over-expression of BCAT1, a c-Myc target gene, induces cell proliferation, migration and invasion in nasopharyngeal carcinoma 
Molecular Cancer  2013;12:53.
Nasopharyngeal carcinoma (NPC) is a common malignant tumor in southern China and Southeast Asia, but its molecular mechanisms of pathogenesis are poorly understood. Our previous work has demonstrated that BCAT1 mRNA is over expressed in NPC and knocking down its expression in 5-8F NPC cell line can potently inhibit cell cycle progression and cell proliferation. However, the mechanism of BCAT1 up-regulation and its functional role in NPC development remain to be elucidated yet.
Immunohistochemistry (IHC) method was utilized to detect the expression of BCAT1 protein in NPC at different pathological stages. The roles of gene mutation, DNA amplification and transcription factor c-Myc in regulating BCAT1 expression were analyzed using PCR-sequencing, quantitative polymerase chain reaction (qPCR), IHC, ChIP and luciferase reporter system, respectively. The functions of BCAT1 in colony formation, cell migration and invasion properties were evaluated by RNA interference (RNAi).
The positive rates of BCAT1 protein expression in normal epithelia, low-to-moderate grade atypical hyperplasia tissues, high-grade atypical hyperplasia tissues and NPC tissues were 23.6% (17/72), 75% (18/24 ), 88.9% (8/9) and 88.8% (71/80), respectively. Only one SNP site in exon1 was detected, and 42.4% (12/28) of the NPC tissues displayed the amplification of microsatellite loci in BCAT1. C-Myc could directly bind to the c-Myc binding site in promoter region of BCAT1 and up-regulate its expression. The mRNA and protein of c-Myc and BCAT1 were co-expressed in 53.6% (15/28) and 59.1% (13/22) of NPC tissues, respectively, and BCAT1 mRNA expression was also down-regulated in c-Myc knockdown cell lines. In addition, BCAT1 knockdown cells demonstrated reduced proliferation and decreased cell migration and invasion abilities.
Our study indicates that gene amplification and c-Myc up-regulation are responsible for BCAT1 overexpression in primary NPC, and overexpression of BCAT1 induces cell proliferation, migration and invasion. The results suggest that BCAT1 may be a novel molecular target for the diagnosis and treatment of NPC.
PMCID: PMC3698204  PMID: 23758864
Nasopharyngeal carcinoma; BCAT1; c-Myc; Proliferation; Migration; Invasion; Gene amplification; Gene regulation
2.  Genome sequence of the date palm Phoenix dactylifera L 
Nature Communications  2013;4:2274.
Date palm (Phoenix dactylifera L.) is a cultivated woody plant species with agricultural and economic importance. Here we report a genome assembly for an elite variety (Khalas), which is 605.4 Mb in size and covers >90% of the genome (~671 Mb) and >96% of its genes (~41,660 genes). Genomic sequence analysis demonstrates that P. dactylifera experienced a clear genome-wide duplication after either ancient whole genome duplications or massive segmental duplications. Genetic diversity analysis indicates that its stress resistance and sugar metabolism-related genes tend to be enriched in the chromosomal regions where the density of single-nucleotide polymorphisms is relatively low. Using transcriptomic data, we also illustrate the date palm’s unique sugar metabolism that underlies fruit development and ripening. Our large-scale genomic and transcriptomic data pave the way for further genomic studies not only on P. dactylifera but also other Arecaceae plants.
The date palm is one of the most economically important plants of the palm family. Here, the authors present a high-quality genome assembly of the date palm Phoenix dactylifera, and reveal insights into the unique sugar metabolism underlying fruit ripening.
PMCID: PMC3741641  PMID: 23917264
3.  The Limbic-Prefrontal Network Modulated by Electroacupuncture at CV4 and CV12 
fMRI studies showed that acupuncture could induce hemodynamic changes in brain networks. Many of these studies focused on whether specific acupoints could activate specific brain regions and were often limited to manual acupuncture at acupoints on the limbs. In this fMRI study, we investigated acupuncture's modulation effects on brain functional networks by electroacupuncture (EA) at acupoints on the midline of abdomen. Acupoints Guanyuan (CV4) and Zhongwan (CV12) were stimulated in 21 healthy volunteers. The needling sensations, brain activation, and functional connectivity were studied. We found that the limbic-prefrontal functional network was deactivated by EA at CV4 and CV12. More importantly, the local functional connectivity was significantly changed during EA stimulation, and the change persisted during the period after the stimulation. Although minor differences existed, both acupoints similarly modulated the limbic-prefrontal functional network, which is overlapped with the functional circuits associated with emotional and cognitive regulation.
PMCID: PMC3265182  PMID: 22291848
4.  Genomic and Proteomic Analyses of the Fungus Arthrobotrys oligospora Provide Insights into Nematode-Trap Formation 
PLoS Pathogens  2011;7(9):e1002179.
Nematode-trapping fungi are “carnivorous” and attack their hosts using specialized trapping devices. The morphological development of these traps is the key indicator of their switch from saprophytic to predacious lifestyles. Here, the genome of the nematode-trapping fungus Arthrobotrys oligospora Fres. (ATCC24927) was reported. The genome contains 40.07 Mb assembled sequence with 11,479 predicted genes. Comparative analysis showed that A. oligospora shared many more genes with pathogenic fungi than with non-pathogenic fungi. Specifically, compared to several sequenced ascomycete fungi, the A. oligospora genome has a larger number of pathogenicity-related genes in the subtilisin, cellulase, cellobiohydrolase, and pectinesterase gene families. Searching against the pathogen-host interaction gene database identified 398 homologous genes involved in pathogenicity in other fungi. The analysis of repetitive sequences provided evidence for repeat-induced point mutations in A. oligospora. Proteomic and quantitative PCR (qPCR) analyses revealed that 90 genes were significantly up-regulated at the early stage of trap-formation by nematode extracts and most of these genes were involved in translation, amino acid metabolism, carbohydrate metabolism, cell wall and membrane biogenesis. Based on the combined genomic, proteomic and qPCR data, a model for the formation of nematode trapping device in this fungus was proposed. In this model, multiple fungal signal transduction pathways are activated by its nematode prey to further regulate downstream genes associated with diverse cellular processes such as energy metabolism, biosynthesis of the cell wall and adhesive proteins, cell division, glycerol accumulation and peroxisome biogenesis. This study will facilitate the identification of pathogenicity-related genes and provide a broad foundation for understanding the molecular and evolutionary mechanisms underlying fungi-nematodes interactions.
Author Summary
The fungus Arthrobotrys oligospora has multiple lifestyles. It's not only a nematode pathogen, but also a saprophyte, a pathogen of other fungi, and a colonizer of plant roots. As a nematode pathogen, A. oligospora forms adhesive networks to capture nematodes and is a model organism for understanding the interaction between these fungi and their host nematodes. In this study, the whole genome sequence of A. oligospora was reported. Our analyses of the proteome profiles of intracellular proteins from cells treated with nematode extracts for 10 h and 48 h revealed a key set of genes involved in trap formation. The changes in protein levels for some trap formation related genes were further confirmed by qPCR. The combined genome and proteome analysis identified the major genetic and metabolic pathways involved in trap formation in A. oligospora. Our results provide the first glimpse into the genome and proteome of this fascinating group of carnivorous fungi. The data should serve as a roadmap for further investigations into the interaction between nematode-trapping fungi and their host nematodes, providing broad foundations for research on the biocontrol of pathogenic nematodes.
PMCID: PMC3164635  PMID: 21909256
5.  Fresh raspberry phytochemical extract inhibits hepatic lesion in a Wistar rat model 
Red raspberry possesses potent antioxidant capacity and antiproliferative activity against cancer in vitro.
The objective of this study was to determine the protective effects of raspberry 80% acetone extract in a rat hepatic lesions model induced by diethylnitrosamine (DEN). Rats were treated with the red raspberry extract (0.75, 1.5 or 3.0 g/kg of body weight) by gavage starting 2 h after DEN administration and continuing for 20 weeks.
A dose-dependent inhibition by red raspberry extract of DEN-induced hepatic nodule formation which stands for hepatic lesions was observed. Corresponding hepatic nodule incidence rates were 45.0, 40.0, 25.0 and 5.0% in positive control, low, middle and high groups, respectively (P < 0.01 or 0.05). Gross findings, histopathological and ultrastructural evaluations of hepatic lesion were performed on 9, 8, 5 and 1 hepatic nodule in positive control, low, middle and high doses of groups, respectively, identified in rats from the respective groups of 20. A decreasing trend of proportions of hepatocellular carcinoma masses accompanied the increasing doses of red raspberry extract.
These findings demonstrate that the potent capacity of red raspberry diet could not only suppress DEN-induced hepatic lesions in rats, but also reduce the definite diagnostic features of neoplasm.
PMCID: PMC2999596  PMID: 21108811
6.  Differential expression of proteomics models of colorectal cancer, colorectal benign disease and healthy controls 
Proteome Science  2010;8:16.
Colorectal cancer (CRC) is often diagnosed at a late stage with concomitant poor prognosis. The hypersensitive analytical technique of proteomics can detect molecular changes before the tumor is palpable. The surface-enhanced laser desorption/ionization-time of flight-mass spectra (SELDI-TOF-MS) is a newly-developed technique of evaluating protein separation in recent years. The protein chips have established the expression of tumor protein in the serum specimens and become the newly discovered markers for tumor diagnosis. The objective of this study was to find new markers of the diagnosis among groups of CRC, colorectal benign diseases (CBD) and healthy controls. The assay of SELDI-TOF-MS with analytical technique of protein-chip bioinformatics was used to detect the expression of protein mass peaks in the sera of patients or controls. One hundred serum samples, including 52 cases of colorectal cancer, 27 cases of colorectal benign disease, and 21 cases of healthy controls, were examined by SELDI-TOF-MS with WCX2 protein-chips.
The diagnostic models (I, II and III) were setup by analyzed the data and sieved markers using Ciphergen - Protein-Chip-Software 5.1. These models were combined with 3 protein mass peaks to discriminate CRC, CBD, and healthy controls. The accuracy, the sensitivity and the particularity of cross verification of these models are all highly over 80%.
The SELDI-TOF-MS is a useful tool to help diagnose colorectal cancer, especially during the early stage. However, identification of the significantly differentiated proteins needs further study.
PMCID: PMC2862023  PMID: 20334691
7.  Effects of Yinchenhao Tang and related decoctions on DMN-induced cirrhosis/fibrosis in rats 
Chinese Medicine  2008;3:1.
Chinese medicine decoctions such as Yinchenhao Tang (YCHT), Xiayuxue Tang (XYXT), Huangqi Tang (HQT), Yiguan Jian (YGJ) and Xiaochaihu Tang (XCHT)) were used to treat liver cirrhosis. The present study evaluates the effects of these decoctions on fibrosis in rats induced by dimethylnitrosamine (DMN).
DMN solution (0.5%) was injected to rats for three consecutive days per week for four weeks. At the beginning of week 3, rats were randomly divided into 4-week DMN control group, YCHT, XYXT, HQT, YGJ, XCHT and vehicle groups. Each group was orally administered with specific decoctions daily for two weeks. Rats in the vehicle group were orally administered with only water.
Liver fibrosis and cirrhosis were observed in weeks 2 and 4 in DMN-intoxicated rats. Compared with normal rats, alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) activities and level of total bilirubin acid (TBA) in serum and content of Hydroxyproline (Hyp) in liver tissue of model group rats rose significantly. However, the albumin (Alb) level in serum decreased significantly. Compared with the 4-week DMN group, the pathological conditions and functions of the liver in the YCHT group improved significantly, and the content of Hyp decreased remarkably: only one rat in this group developed liver cirrhosis and the ratio of cirrhosis was only 8.3%. On the other hand, the other decoctions did not show remarkable effects. YCHT inhibited α-SMA activation, including its gene expression into mRNA and protein.
Among the five Chinese medicine decoctions, YCHT exerted the most significant therapeutic effects on DMN-induced cirrhosis/fibrosis in rats.
PMCID: PMC2267793  PMID: 18237412
8.  DNA Microarray-Based Identification of Serogroups and Virulence Gene Patterns of Escherichia coli Isolates Associated with Porcine Postweaning Diarrhea and Edema Disease▿ †  
Applied and Environmental Microbiology  2007;73(12):4082-4088.
Escherichia coli strains causing postweaning diarrhea (PWD) and edema disease (ED) in pigs are limited to a number of serogroups, with O8, O45, O138, O139, O141, O147, O149, and O157 being the most commonly reported worldwide. In this study, a DNA microarray based on the O-antigen-specific genes of all 8 E. coli serogroups, as well as 11 genes encoding adhesion factors and exotoxins associated with PWD and ED, was developed for the identification of related serogroups and virulence gene patterns. The microarray method was tested against 186 E. coli and Shigella O-serogroup reference strains, 13 E. coli reference strains for virulence markers, 43 E. coli clinical isolates, and 12 strains of other bacterial species and shown to be highly specific with reproducible results. The detection sensitivity was 0.1 ng of genomic DNA or 103 CFU per 0.3 g of porcine feces in mock samples. Seventeen porcine feces samples from local hoggeries were examined using the microarray, and the result for one sample was verified by the conventional serotyping methods. This microarray can be readily used to screen for the presence of PWD- and ED-associated E. coli in porcine feces samples.
PMCID: PMC1932722  PMID: 17449692
9.  Development of a Serotype-Specific DNA Microarray for Identification of Some Shigella and Pathogenic Escherichia coli Strains▿  
Journal of Clinical Microbiology  2006;44(12):4376-4383.
Shigella and pathogenic Escherichia coli are major causes of human infectious diseases and are responsible for millions of cases of diarrhea worldwide every year. A convenient and rapid method to identify highly pathogenic serotypes of Shigella and E. coli is needed for large-scale epidemiologic study, timely clinical diagnosis, and reliable quarantine of the pathogens. In this study, a DNA microarray targeting O-serotype-specific genes was developed to detect 15 serotypes of Shigella and E. coli, including Shigella sonnei; Shigella flexneri type 2a; Shigella boydii types 7, 9, 13, 16, and 18; Shigella dysenteriae types 4, 8, and 10; and E. coli O55, O111, O114, O128, and O157. The microarray was tested against 186 representative strains of all Shigella and E. coli O serotypes, 38 clinical isolates, and 9 strains of other bacterial species that are commonly present in stool samples and was shown to be specific and reproducible. The detection sensitivity was 50 ng genomic DNA or 104 CFU per ml in mock stool specimens. This is the first report of a microarray for serotyping Shigella and pathogenic E. coli. The method has a number of advantages over traditional bacterial culture and antiserum agglutination methods and is promising for applications in basic microbiological research, clinical diagnosis, food safety, and epidemiological surveillance.
PMCID: PMC1698391  PMID: 17021058
10.  Complete Genome Sequence of Magnetospirillum gryphiswaldense MSR-1 
Genome Announcements  2014;2(2):e00171-14.
We report the complete genomic sequence of Magnetospirillum gryphiswaldense MSR-1 (DSM 6361), a type strain of the genus Magnetospirillum belonging to the Alphaproteobacteria. Compared to the reported draft sequence, extensive rearrangements and differences were found, indicating high genomic flexibility and “domestication” by accelerated evolution of the strain upon repeated passaging.
PMCID: PMC3953193  PMID: 24625872
11.  GSK3β Overexpression Indicates Poor Prognosis and Its Inhibition Reduces Cell Proliferation and Survival of Non-Small Cell Lung Cancer Cells 
PLoS ONE  2014;9(3):e91231.
Glycogen synthase kinase 3 beta (GSK3β) is centrally involved in diverse cellular processes, including proliferation and apoptosis. This study aimed to investigate the influence of GSK3β expression on the prognosis of human non-small cell lung cancer (NSCLC) and the effects of GSK3β inhibition in NSCLC cell lines.
Immunohistochemical and western blot assays were used to evaluate the GSK3β expression level in human NSCLC tissues. Lentiviral RNA interference was performed to inhibit the expression of GSK3β in the A549, H292, H1299 and SK-MES-1 cell lines. Cell survival, apoptosis and motility were evaluated in vivo and in vitro.
The levels of GSK3β were greater in NSCLC tissues (n = 211) than in control tissues (n = 194) (P<0.001). The 5-year follow-up analysis showed that positive GSK3β expression was indicative of poor prognosis (P = 0.006). Furthermore, knockdown of GSK3β in NSCLC cell lines suppressed cell proliferation, arrested tumor cells in G0/G1 phase, induced apoptosis and reduced cell motility. A xenograft model showed that the deregulation of GSK3β attenuated tumorigenesis, as confirmed by reduced cell proliferation based on Ki-67 and significantly increased apoptotic cell death. The inhibition of GSK3β had inconsistent effects on the expression of β-catenin, depending on the cell type examined.
Aberrant expression of GSK3β serves as an independent marker of poor prognosis for NSCLC. The inhibition of GSK3β suppressed tumorigenesis by attenuating cell proliferation, increasing apoptosis and restraining cell motility. These results identify GSK3β as a tumor promoter and a potential therapeutic target in NSCLC.
PMCID: PMC3949982  PMID: 24618715
12.  Development of a DNA Microarray for Molecular Identification of All 46 Salmonella O Serogroups 
Applied and Environmental Microbiology  2013;79(11):3392-3399.
Salmonella is a major cause of food-borne disease in many countries. Serotype determination of Salmonella is important for disease assessment, infection control, and epidemiological surveillance. In this study, a microarray system that targets the O antigen-specific genes was developed for simultaneously detecting and identifying all 46 Salmonella O serogroups. Of these, 40 serogroups can be confidently identified, and the remaining 6, in three pairs (serogroups O67 and B, E1 and E4, and A and D1), need to be further distinguished from each other using PCR methods or conventional serotyping methods. The microarray was shown to be highly specific when evaluated against 293 Salmonella strains, 186 Shigella strains, representative Escherichia coli strains, and 10 strains of other bacterial species. The assay correctly identified 288 (98%) of the Salmonella strains. The detection sensitivity was determined to be 50 ng genomic DNA per sample. By testing simulated samples in a tomato background, 2 to 8 CFU per gram inoculated could be detected after enrichment. This newly developed microarray assay is the first molecular protocol that can be used for the comprehensive detection and identification of all 46 Salmonella O serogroups. Compared to the traditional serogrouping method, the microarray provides a reliable, high-throughput, and sensitive approach that can be used for rapid identification of multiple Salmonella O serogroups simultaneously.
PMCID: PMC3648052  PMID: 23524674
13.  Adsorption of Cu(II) on Oxidized Multi-Walled Carbon Nanotubes in the Presence of Hydroxylated and Carboxylated Fullerenes 
PLoS ONE  2013;8(8):e72475.
The adsorption of Cu(II) on oxidized multi-walled carbon nanotubes (oMWCNTs) as a function of contact time, pH, ionic strength, temperature, and hydroxylated fullerene (C60(OH)n) and carboxylated fullerene (C60(C(COOH)2)n) were studied under ambient conditions using batch techniques. The results showed that the adsorption of Cu(II) had rapidly reached equilibrium and the kinetic process was well described by a pseudo-second-order rate model. Cu(II) adsorption on oMWCNTs was dependent on pH but independent of ionic strength. Compared with the Freundlich model, the Langmuir model was more suitable for analyzing the adsorption isotherms. The thermodynamic parameters calculated from temperature-dependent adsorption isotherms suggested that Cu(II) adsorption on oMWCNTs was spontaneous and endothermic. The effect of C60(OH)n on Cu(II) adsorption of oMWCNTs was not significant at low C60(OH)n concentration, whereas a negative effect was observed at higher concentration. The adsorption of Cu(II) on oMWCNTs was enhanced with increasing pH values at pH < 5, but decreased at pH ≥ 5. The presence of C60(C(COOH)2)n inhibited the adsorption of Cu(II) onto oMWCNTs at pH 4–6. The double sorption site model was applied to simulate the adsorption isotherms of Cu(II) in the presence of C60(OH)n and fitted the experimental data well.
PMCID: PMC3756995  PMID: 24009683
14.  The application of hyaluronic acid-derivatized carbon nanotubes in hematoporphyrin monomethyl ether-based photodynamic therapy for in vivo and in vitro cancer treatment 
Carbon nanotubes (CNTs) have shown great potential in both photothermal therapy and drug delivery. In this study, a CNT derivative, hyaluronic acid-derivatized CNTs (HA-CNTs) with high aqueous solubility, neutral pH, and tumor-targeting activity, were synthesized and characterized, and then a new photodynamic therapy agent, hematoporphyrin monomethyl ether (HMME), was adsorbed onto the functionalized CNTs to develop HMME-HA-CNTs. Tumor growth inhibition was investigated both in vivo and in vitro by a combination of photothermal therapy and photodynamic therapy using HMME-HA-CNTs. The ability of HMME-HA-CNT nanoparticles to combine local specific photodynamic therapy with external near-infrared photothermal therapy significantly improved the therapeutic efficacy of cancer treatment. Compared with photodynamic therapy or photothermal therapy alone, the combined treatment demonstrated a synergistic effect, resulting in higher therapeutic efficacy without obvious toxic effects to normal organs. Overall, it was demonstrated that HMME-HA-CNTs could be successfully applied to photodynamic therapy and photothermal therapy simultaneously in future tumor therapy.
PMCID: PMC3702246  PMID: 23843694
photodynamic therapy; photothermal therapy; HA-derivatized carbon nanotubes; tumor targeting; synergistic effect; hematoporphyrin monomethyl ether
15.  PTEN Loss Increases PD-L1 Protein Expression and Affects the Correlation between PD-L1 Expression and Clinical Parameters in Colorectal Cancer 
PLoS ONE  2013;8(6):e65821.
Programmed death ligand-1 (PD-L1) has been identified as a factor associated with poor prognosis in a range of cancers, and was reported to be mainly induced by PTEN loss in gliomas. However, the clinical effect of PD-L1 and its regulation by PTEN has not yet been determined in colorectal cancer (CRC). In the present study, we verified the regulation of PTEN on PD-L1 and further determined the effect of PTEN on the correlation between PD-L1 expression and clinical parameters in CRC.
RNA interference approach was used to down-regulate PTEN expression in SW480, SW620 and HCT116 cells. It was showed that PD-L1 protein, but not mRNA, was significantly increased in cells transfected with siRNA PTEN compared with the negative control. Moreover, the capacity of PTEN to regulate PD-L1 expression was not obviously affected by IFN-γ, the main inducer of PD-L1. Tissue microarray immunohistochemistry was used to detect PD-L1 and PTEN in 404 CRC patient samples. Overexpression of PD-L1 was significantly correlated with distant metastasis (P<0.001), TNM stage (P<0.01), metastatic progression (P<0.01) and PTEN expression (P<0.001). Univariate analysis revealed that patients with high PD-L1 expression had a poor overall survival (P<0.001). However, multivariate analysis did not support PD-L1 as an independent prognostic factor (P = 0.548). Univariate (P<0.001) and multivariate survival (P<0.001) analysis of 310 located CRC patients revealed that high level of PD-L1 expression was associated with increased risks of metastatic progression. Furthermore, the clinical effect of PD-L1 on CRC was not statistically significant in a subset of 39 patients with no PTEN expression (distant metastasis: P = 0.102; TNM stage: P = 0.634, overall survival: P = 0.482).
PD-L1 can be used to identify CRC patients with high risk of metastasis and poor prognosis. This clinical manifestation may be partly associated with PTEN expression.
PMCID: PMC3681867  PMID: 23785454
16.  Activated N-Ras signaling regulates arterial-venous specification in zebrafish 
The aberrant activation of Ras signaling is associated with human diseases including hematological malignancies and vascular disorders. So far the pathological roles of activated Ras signaling in hematopoiesis and vasculogenesis are largely unknown.
A conditional Cre/loxP transgenic strategy was used to mediate the specific expression of a constitutively active form of human N-Ras in zebrafish endothelial and hematopoietic cells driven by the zebrafish lmo2 promoter. The expression of hematopoietic and endothelial marker genes was analyzed both via whole mount in situ hybridization (WISH) assay and real-time quantitative PCR (qPCR). The embryonic vascular morphogenesis was characterized both by living imaging and immunofluorescence on the sections with a confocal microscopy, and the number of endothelial cells in the embryos was quantified by flow cytometry. The functional analyses of the blood circulation were carried out by fluorescence microangiography assay and morpholino injection.
In the activated N-Ras transgenic embryos, the primitive hematopoiesis appeared normal, however, the definitive hematopoiesis of these embryos was completely absent. Further analysis of endothelial cell markers confirmed that transcription of arterial marker ephrinB2 was significantly decreased and expression of venous marker flt4 excessively increased, indicating the activated N-Ras signaling promotes the venous development at the expense of arteriogenesis during zebrafish embryogenesis. The activated N-Ras-expressing embryos showed atrophic axial arteries and expansive axial veins, leading to no definitive hematopoietic stem cell formation, the blood circulation failure and subsequently embryonic lethality.
Our studies revealed for the first time that activated N-Ras signaling during the endothelial differentiation in vertebrates can disrupt the balance of arterial-venous specification, thus providing new insights into the pathogenesis of the congenital human vascular disease and tumorigenic angiogenesis.
PMCID: PMC3658992  PMID: 23663822
Vasculogenesis; Arteriogenesis; N-Ras
17.  Characterization of the Interaction between Cadmium and Chlorpyrifos with Integrative Techniques in Incurring Synergistic Hepatoxicity 
PLoS ONE  2013;8(3):e59553.
Mixture toxicity is an important issue for the risk assessment of environmental pollutants, for which an extensive amount of data are necessary in evaluating their potential adverse health effects. However, it is very hard to decipher the interaction between compounds due to limited techniques. Contamination of heavy metals and organophosphoric insecticides under the environmental and biological settings poses substantial health risk to humans. Although previous studies demonstrated the co-occurrence of cadmium (Cd) and chlorpyrifos (CPF) in environmental medium and food chains, their interaction and potentially synergistic toxicity remain elusive thus far. Here we integrated the approaches of thin-layer chromatography and 1H NMR to study the interaction between Cd2+ and CPF in inducing hepatoxicity. A novel interaction was identified between Cd2+ and CPF, which might be the bonding between Cd2+ and nitrogen atom in the pyridine ring of CPF, or the chelation formation between one Cd2+ and two CPF molecules. The Cd-CPF complex was conferred with distinct biological fate and toxicological performances from its parental components. We further demonstrated that the joint hepatoxicity of Cd ion and CPF was chiefly due to the Cd-CPF complex-facilitated intracellular transport associated with oxidative stress.
PMCID: PMC3597607  PMID: 23516638
18.  Characterization of De Qi with Electroacupuncture at Acupoints with Different Properties 
This study sought to explore the characteristics of de qi using electroacupuncture at acupoints with different properties in the meridian category, histological type, and nerve innervations.
Electroacupuncture was performed on 21 healthy volunteers at paired acupoints of ST36-GB34, CV4-CV12, ST36-ST28, PC6-PC7, and ST36-CV4. Upon acupuncture de qi, the intensities and the prevalence of individual sensations, sensation transmission, and the amplitude of electrical current were recorded. Chi-square, Fischer's exact test, Wilcoxon test, and two-sample paired t test were used to compare the components of de qi within each paired group.
Overall intensities and prevalence of individual sensations are fullness, numbness, soreness, tingling, heaviness, pressure, dull pain, warmness, and coolness in decreasing order. No significant difference was found in the prevalence of needling sensations between the two paired points (p>0.05). However, significant intensity differences (p<0.05) were showed in soreness, fullness, and heaviness between ST36-ST28, in fullness and numbness between ST36-CV4, and in fullness between CV4-CV12. Tingling sensation was stronger than heaviness and pressure at acupoints PC6-PC7 and ST36 (as paired with CV4). Sharp pain occurred in 10/216 tests (4.63%). Sensation transmission occurred highly (77.78%) on participants, and sensations mostly propagate over one joint but no further than two joints. Overall electrical current was 2.35±0.07 mA (mean±standard error). No significant difference was found between paired acupoints for the distance of sensation transmission and the amplitude of electrical current.
Fullness, numbness, and soreness were the most common and obvious sensations associated with electroacupuncture. The difference of sensation intensities may be associated with different nerve innervations.
PMCID: PMC3221509  PMID: 21999154
19.  Identification and characterization of neuroblasts in the subventricular zone and rostral migratory stream of the adult human brain 
Cell Research  2011;21(11):1534-1550.
It is of great interest to identify new neurons in the adult human brain, but the persistence of neurogenesis in the subventricular zone (SVZ) and the existence of the rostral migratory stream (RMS)-like pathway in the adult human forebrain remain highly controversial. In the present study, we have described the general configuration of the RMS in adult monkey, fetal human and adult human brains. We provide evidence that neuroblasts exist continuously in the anterior ventral SVZ and RMS of the adult human brain. The neuroblasts appear singly or in pairs without forming chains; they exhibit migratory morphologies and co-express the immature neuronal markers doublecortin, polysialylated neural cell adhesion molecule and βIII-tubulin. Few of these neuroblasts appear to be actively proliferating in the anterior ventral SVZ but none in the RMS, indicating that neuroblasts distributed along the RMS are most likely derived from the ventral SVZ. Interestingly, no neuroblasts are found in the adult human olfactory bulb. Taken together, our data suggest that the SVZ maintains the ability to produce neuroblasts in the adult human brain.
PMCID: PMC3365638  PMID: 21577236
human; rhesus monkey; stem cells; neurogenesis; neuroblasts; subventricular zone; rostral migratory stream
20.  Influences of lamin A levels on induction of pluripotent stem cells 
Biology Open  2012;1(11):1118-1127.
Lamin A is an inner nuclear membrane protein that maintains nuclear structure integrity, is involved in transcription, DNA damage response and genomic stability, and also links to cell differentiation, senescence, premature aging and associated diseases. Induced pluripotent stem (iPS) cells have been successfully generated from various types of cells and used to model human diseases. It remains unclear whether levels of lamin A influence reprogramming of somatic cells to pluripotent states during iPS induction. Consistently, lamin A is expressed more in differentiated than in relatively undifferentiated somatic cells, and increases in expression levels with age. Somatic cells with various expression levels of lamin A differ in their dynamics and efficiency during iPS cell induction. Cells with higher levels of lamin A show slower reprogramming and decreased efficiency to iPS cells. Furthermore, depletion of lamin A by transient shRNA accelerates iPS cell induction from fibroblasts. Reduced levels of lamin A are associated with increased expression of pluripotent genes Oct4 and Nanog, and telomerase genes Tert and Terc. On the contrary, overexpression of lamin A retards somatic cell reprogramming to iPS-like colony formation. Our data suggest that levels of lamin A influence reprogramming of somatic cells to pluripotent stem cells and that artificial silencing of lamin A facilitates iPS cell induction. These findings may have implications in enhancing rejuvenation of senescent or older cells by iPS technology and manipulating lamin A levels.
PMCID: PMC3507184  PMID: 23213392
Lamin A; Reprogramming; Pluripotency; iPS; ES; Differentiation
21.  Complete Genome Sequence of the Industrial Strain Ketogulonicigenium vulgare WSH-001 
Journal of Bacteriology  2011;193(21):6108-6109.
Ketogulonicigenium vulgare is an industrial organism commonly used in the vitamin C industry. Here, we report the finished, annotated, and compared 3.28-Mbp high-quality genome sequence of Ketogulonicigenium vulgare WSH-001, a 2-keto-l-gulonic acid-producing industrial strain stocked in our laboratory.
PMCID: PMC3194925  PMID: 21994934
22.  Complete Genome Sequence of the Industrial Strain Bacillus megaterium WSH-002 
Journal of Bacteriology  2011;193(22):6389-6390.
Bacillus megaterium, an industrial strain, has been widely used in protein production and the vitamin C industry. Here we reported a finished, annotated, and compared 4.14-Mbp high-quality genome sequence of B. megaterium WSH-002, which is the companion strain for Ketogulonicigenium vulgare in the vitamin C industry and is stocked in our laboratory.
PMCID: PMC3209192  PMID: 22038958
23.  Comparison of one-stage anteroposterior and posterior-alone hemivertebrae resection combined with posterior correction for hemivertebrae deformity 
Indian Journal of Orthopaedics  2011;45(6):492-499.
The surgical technique of hemivertebrae excision varies from anteroposterior procedures to posterior-alone resections according to the experience and preference of surgeons. Both the approaches are reliable and give relatively good results. This study aims to evaluate and compare the clinical and radiological results of these two approaches for hemivertebrae resection.
Materials and Methods:
Sixty patients were retrospectively enrolled between 2006 and 2009. The subjects included 32 women and 28 men, with a mean age of 12.9 years (range: 5–24 years). Thirty patients who underwent one-stage anteroposterior hemivertebrae resection (the AP group) were followed for 38.5 months, and the other 30 patients who underwent posterior resection (the P group) were followed for 20.6 months. Clinical and radiological assessments were performed preoperatively, 1 week postoperatively, and at the final follow-up. The operation time, blood loss, degree of correction of the main curve/segmental curve/kyphosis, the average hospital stay, and complications were reviewed and compared between the two groups.
The mean operation time, blood loss, and hospital stay of the AP group and the P group were 451 min vs 248.5 min, 1290 ml vs 910 ml, and 21.93 days vs 18.97 days, respectively (P<.05). The average correction rate of the main curve/segmental curve/kyphosis of the AP group and the P group was 68.5% vs 66.2%, 71.5% vs 69.6%, and 57.4% vs 56.1%, respectively (P>.05). Overall complication rate was 6.7% in the AP group vs 10% in the P group (P>.05).
Posterior hemivertebrael resection is a promising approach for congenital scoliosis in terms of relative safety, degree of correction achieved, reduced operative time and blood loss.
PMCID: PMC3227350  PMID: 22144739
Hemivertebrae deformity; hemivertebrae resection; anteroposterior resection; posterior resection
24.  Molecular Behavior of DNA Origami in Higher-Order Self-Assembly 
Journal of the American Chemical Society  2010;132(38):13545-13552.
DNA-based self-assembly is a unique method for achieving higher-order molecular architectures made possible by the fact that DNA is a programmable information-coding polymer. In the past decade, two main types of DNA nanostructures have been developed: branch-shaped DNA tiles with small dimensions (commonly up to ~20 nm) and DNA origami tiles with larger dimensions (up to ~100 nm). Here we aimed to determine the important factors involved in the assembly of DNA origami superstructures. We constructed a new series of rectangular-shaped DNA origami tiles in which parallel DNA helices are arranged in a zigzag pattern when viewed along the DNA helical axis, a design conceived in order to relax an intrinsic global twist found in the original planar, rectangular origami tiles. Self-associating zigzag tiles were found to form linear arrays in both diagonal directions, while planar tiles showed significant growth in only one direction. Although the series of zigzag tiles were designed to promote two-dimensional array formation, one-dimensional linear arrays and tubular structures were observed instead. We discovered that the dimensional aspect ratio of the origami unit tiles and intertile connection design play important roles in determining the final products, as revealed by atomic force microscopy imaging. This study provides insight into the formation of higher-order structures from self-assembling DNA origami tiles, revealing their unique behavior in comparison with conventional DNA tiles having smaller dimensions.
PMCID: PMC3071357  PMID: 20825190
25.  The draft genome of the transgenic tropical fruit tree papaya (Carica papaya Linnaeus) 
Ming, Ray | Hou, Shaobin | Feng, Yun | Yu, Qingyi | Dionne-Laporte, Alexandre | Saw, Jimmy H. | Senin, Pavel | Wang, Wei | Ly, Benjamin V. | Lewis, Kanako L. T. | Salzberg, Steven L. | Feng, Lu | Jones, Meghan R. | Skelton, Rachel L. | Murray, Jan E. | Chen, Cuixia | Qian, Wubin | Shen, Junguo | Du, Peng | Eustice, Moriah | Tong, Eric | Tang, Haibao | Lyons, Eric | Paull, Robert E. | Michael, Todd P. | Wall, Kerr | Rice, Danny W. | Albert, Henrik | Wang, Ming-Li | Zhu, Yun J. | Schatz, Michael | Nagarajan, Niranjan | Acob, Ricelle A. | Guan, Peizhu | Blas, Andrea | Wai, Ching Man | Ackerman, Christine M. | Ren, Yan | Liu, Chao | Wang, Jianmei | Wang, Jianping | Na, Jong-Kuk | Shakirov, Eugene V. | Haas, Brian | Thimmapuram, Jyothi | Nelson, David | Wang, Xiyin | Bowers, John E. | Gschwend, Andrea R. | Delcher, Arthur L. | Singh, Ratnesh | Suzuki, Jon Y. | Tripathi, Savarni | Neupane, Kabi | Wei, Hairong | Irikura, Beth | Paidi, Maya | Jiang, Ning | Zhang, Wenli | Presting, Gernot | Windsor, Aaron | Navajas-Pérez, Rafael | Torres, Manuel J. | Feltus, F. Alex | Porter, Brad | Li, Yingjun | Burroughs, A. Max | Luo, Ming-Cheng | Liu, Lei | Christopher, David A. | Mount, Stephen M. | Moore, Paul H. | Sugimura, Tak | Jiang, Jiming | Schuler, Mary A. | Friedman, Vikki | Mitchell-Olds, Thomas | Shippen, Dorothy E. | dePamphilis, Claude W. | Palmer, Jeffrey D. | Freeling, Michael | Paterson, Andrew H. | Gonsalves, Dennis | Wang, Lei | Alam, Maqsudul
Nature  2008;452(7190):991-996.
Papaya, a fruit crop cultivated in tropical and subtropical regions, is known for its nutritional benefits and medicinal applications. Here we report a 3× draft genome sequence of ‘SunUp’ papaya, the first commercial virus-resistant transgenic fruit tree1 to be sequenced. The papaya genome is three times the size of the Arabidopsis genome, but contains fewer genes, including significantly fewer disease-resistance gene analogues. Comparison of the five sequenced genomes suggests a minimal angiosperm gene set of 13,311. A lack of recent genome duplication, atypical of other angiosperm genomes sequenced so far2–5, may account for the smaller papaya gene number in most functional groups. Nonetheless, striking amplifications in gene number within particular functional groups suggest roles in the evolution of tree-like habit, deposition and remobilization of starch reserves, attraction of seed dispersal agents, and adaptation to tropical daylengths. Transgenesis at three locations is closely associated with chloroplast insertions into the nuclear genome, and with topoisomerase I recognition sites. Papaya offers numerous advantages as a system for fruit-tree functional genomics, and this draft genome sequence provides the foundation for revealing the basis of Carica's distinguishing morpho-physiological, medicinal and nutritional properties.
PMCID: PMC2836516  PMID: 18432245

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