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1.  Arabidopsis phospholipase Dβ1 modulates defense responses to bacterial and fungal pathogens 
The New phytologist  2013;199(1):228-240.
Pathogen infection of higher plants often induces a rapid production of phosphatic acid (PA) and changes in lipid profiles, but the enzymatic basis and the function of the lipid change in pathogen-plant interactions are not well understood.Infection of PLDβ1-deficient plants by Pseudomonas syringae pv. DC3000 resulted in less bacterial growth than in wild-type plants, and the effect was more profound in virulent Pst DC3000 than avirulent Pst DC3000 (avrRpt2) infection. The expression levels of salicylic acid (SA)-inducible genes were higher, but those inducible by jasmonic acid (JA) were lower in PLDβ1 mutants than in wild-type plants.However, PLDβ1-deficient plants were more susceptible than wild-type plants to the fungus Botrytis cinerea. The PLDβ1-deficient plants had lower levels of PA, JA and JA-related defense gene expression after B. cinerea inoculation.PLDβ1 plays a positive role in pathogen-induced JA production and plant resistance to necrotrophic fungal pathogen B. cinerea, but a negative role in the SA-dependent signaling pathway and plant tolerance to the infection of biotrophic Pst DC3000. PLDβ1 is responsible for the major part of PA increased in response to necrotrophic B. cinerea and virulent Pst DC3000 infection, but contributes less to the avirulent Pst DC3000 (avrRpt2)-induced PA production.
PMCID: PMC4066384  PMID: 23577648
Botrytis cinerea; Pseudomonas syringae; Arabidopsis thaliana; phospholipase Dβ1; pathogeneses; phosphatidic acid; lysophospholipids; lipid signaling
2.  Role of miR-146a in human chondrocyte apoptosis in response to mechanical pressure injury in vitro 
MicroRNA (miR)-146a is known to be overexpressed in osteoarthritis (OA). However, the role of miR-146a in OA has not yet been fully elucidated. In the present study, we applied mechanical pressure of 10 MPa to human chondrocytes for 60 min in order to investigate the expression of miR-146a and apoptosis following the mechanical pressure injury. Normal human chondrocytes were transfected with an miR-146a mimic or an inhibitor to regulate miR-146a expression. Potential target genes of miR-146a were predicted using bioinformatics. Moreover, luciferase reporter assay confirmed that Smad4 was a direct target of miR-146a. The expression levels of miR-146a, Smad4 and vascular endothelial growth factor (VEGF) were quantified by quantitative reverse transcription PCR and/or western blot analysis. The effects of miR-146a on apoptosis were detected by Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) flow cytometry. The results indicated that mechanical pressure affected chondrocyte viability and induced the early apoptosis of chondrocytes. Mechanical pressure injury increased the expression levels of miR-146a and VEGF and decreased the levels of Smad4 in the chondrocytes. In the human chondrocytes, the upregulation of miR-146a induced apoptosis, upregulated VEGF expression and downregulated Smad4 expression. In addition, the knockdown of miR-146a reduced cell apoptosis, upregulated Smad4 expression and downregulated VEGF expression. Smad4 was identified as a direct target of miR-146a by harboring a miR-146a binding sequence in the 3′-untranslated region (3′-UTR) of its mRNA. Furthermore, the upregulation of VEGF induced by miR-146a was mediated by Smad4 in the chondrocytes subjected to mechanical pressure injury. These results demonstrated that miR-146a was overexpressed in our chondrocyte model of experimentally induced human mechanical injury, accompanied by the upregulation of VEGF and the downregulation of Smad4 in vitro. Moreover, our data suggest that miR-146a is involved in human chondrocyte apoptosis in response to mechanical injury, and may contribute to the mechanical injury of chondrocytes, as well as to the pathogenesis of OA by increasing the levels of VEGF and damaging the transforming growth factor (TGF)-β signaling pathway through the targeted inhibition of Smad4 in cartilage.
PMCID: PMC4094584  PMID: 24939082
apoptosis; osteoarthritis; mechanical injury; chondrocyte; miR-146a
3.  Generation of neural progenitor cells by chemical cocktails and hypoxia 
Cell Research  2014;24(6):665-679.
Neural progenitor cells (NPCs) can be induced from somatic cells by defined factors. Here we report that NPCs can be generated from mouse embryonic fibroblasts by a chemical cocktail, namely VCR (V, VPA, an inhibitor of HDACs; C, CHIR99021, an inhibitor of GSK-3 kinases and R, Repsox, an inhibitor of TGF-β pathways), under a physiological hypoxic condition. These chemical-induced NPCs (ciNPCs) resemble mouse brain-derived NPCs regarding their proliferative and self-renewing abilities, gene expression profiles, and multipotency for different neuroectodermal lineages in vitro and in vivo. Further experiments reveal that alternative cocktails with inhibitors of histone deacetylation, glycogen synthase kinase, and TGF-β pathways show similar efficacies for ciNPC induction. Moreover, ciNPCs can also be induced from mouse tail-tip fibroblasts and human urinary cells with the same chemical cocktail VCR. Thus our study demonstrates that lineage-specific conversion of somatic cells to NPCs could be achieved by chemical cocktails without introducing exogenous factors.
PMCID: PMC4042166  PMID: 24638034
lineage conversion; neural progenitor cells; chemical cocktails; hypoxia
4.  First Total Syntheses and Antimicrobial Evaluation of Penicimonoterpene, a Marine-Derived Monoterpenoid, and Its Various Derivatives 
Marine Drugs  2014;12(6):3352-3370.
The first total synthesis of marine-derived penicimonoterpene (±)-1 has been achieved in four steps from 6-methylhept-5-en-2-one using a Reformatsky reaction as the key step to construct the basic carbon skeleton. A total of 24 new derivatives of 1 have also been designed and synthesized. Their structures were characterized by analysis of their 1H NMR, 13C NMR and HRESIMS data. Some of them showed significant antibacterial activity against Aeromonas hydrophila, Escherichia coli, Micrococcus luteus, Staphylococcus aureus, Vibrio anguillarum, V. harveyi and/or V. parahaemolyticus, and some showed activity against plant-pathogenic fungi (Alternaria brassicae, Colletotrichum gloeosporioides and/or Fusarium graminearum). Some of the derivatives exhibited antimicrobial MIC values ranging from 0.25 to 4 μg/mL, which were stronger than those of the positive control. Notably, Compounds 3b and 10 showed extremely high selectively against plant-pathogenic fungus F. graminearum (MIC 0.25 μg/mL) and pathogenic bacteria E. coli (MIC 1 μg/mL), implying their potential as antimicrobial agents. SAR analysis of 1 and its derivatives indicated that modification of the carbon-carbon double bond at C-6/7, of groups on the allylic methylene unit and of the carbonyl group at C-1, effectively enhanced the antimicrobial activity.
PMCID: PMC4071580  PMID: 24897384
(±)-penicimonoterpene; total synthesis; antimicrobial activity; structure-activity relationship
5.  Prognostic significance of SUVmax and serum carbohydrate antigen 19-9 in pancreatic cancer 
AIM: To investigate the prognostic significance of pretreatment standardized maximum uptake value (SUVmax) and serum carbohydrate antigen (CA)19-9 in pancreatic cancer.
METHODS: From January 2007 to October 2011, 80 consecutive patients with pancreatic cancer who received positron emission/computed tomography before any treatment were enrolled in this study. The pretreatment SUVmax and CA19-9 level of the primary pancreatic tumor were obtained and compared with clinicopathological and prognostic factors. Student’s t test for unpaired data was used to analyze the differences between two groups. Univariate analysis and Cox proportional hazards regression were used to examine the independent effects of each significant variable. Survival was analyzed by the Kaplan-Meier method.
RESULTS: There was a significant correlation between both the SUVmax and serum CA19-9 of pancreatic cancer and R0 surgical resection (P = 0.043 and P = 0.007). Lymph node metastasis was associated with SUVmax (P = 0.017), but not serum CA19-9 (P = 0.172). On the contrary, the tumor stage was significantly related to serum CA19-9 (P = 0.035), but not SUVmax (P = 0.110). The univariate analysis showed that survival time was significantly related to tumor stage (P < 0.001), lymph node metastasis (P = 0.043), R0 surgical resection (P < 0.001), serum CA19-9 (P = 0.001), SUVmax (P < 0.001) and SUVmax plus CA19-9 (P = 0.002). Multivariate analysis clearly showed that only tumor stage (hazard ratio = 0.452; P = 0.020) was an independent prognostic factor for overall survival in pancreatic cancer. Higher SUVmax or CA19-9 showed worse prognosis. We found that high serum CA19-9 plus SUVmax was the most significant variable.
CONCLUSION: Higher pretreatment SUVmax and serum CA19-9 indicates poor prognosis. SUVmax plus serum CA19-9 is the most significant variable in predicting survival.
PMCID: PMC4024797  PMID: 24914348
Pancreatic cancer; Maximum standardized uptake value; Carbohydrate antigen 19-9; Prognostic factors
6.  Up-regulation of miR-630 in clear cell renal cell carcinoma is associated with lower overall survival 
Introduction: MicroRNAs (miRNAs) are noncoding RNAs that regulate multiple cellular processes during cancer progression. MiR-630 has recently been identified to be involved in tumorigenesis of several cancers such as lung cancer and gastric cancer. However, the regulation of miR-630 in clear cell renal cell carcinoma (ccRCC) has not yet been reported before. Methods: Expression of miR-630 was evaluated by quantitative real-time PCR in tumour and their normal matched tissues in n = 92 ccRCC patients, and its association with overall survival of patients was analyzed by statistical analysis. Results: The expression level of miR-630 was significantly higher in renal cancer in comparison to normal matched tissue (P < 0.05). It is also proved that miR-630 expression was to be associated with renal cancer histologic grade, lymphnode metastasis, distant metastasis (P < 0.05). In addition, the Kaplan-Meier survival curves revealed that high miR-630 expression was associated with poor prognosis in ccRCC patients. miR-630 expression was an independent prognostic marker of overall ccRCC patient survival in a multivariate analysis. Conclusions: The study proves for the first time that miR-630 is upregulated in a majority of ccRCC patients. It also shows that miR-630 expression is an independent prognostic factor for patients with renal cancer, which might be a potential valuable biomarker for ccRCC.
PMCID: PMC4097229  PMID: 25031755
miR-630; clear cell renal cell carcinoma; quantitative real-time PCR; prognosis
7.  Clinical and computed tomography features of adult abdominopelvic desmoplastic small round cell tumor 
To investigate the clinical and computed tomography (CT) features of desmoplastic small round cell tumor (DSRCT), we retrospectively analyzed the clinical presentations, treatment and outcome, as well as CT manifestations of four cases of DSRCT confirmed by surgery and pathology. The CT manifestations of DSRCT were as follows: (1) multiple soft-tissue masses or diffuse peritoneal thickening in the abdomen and pelvis, with the dominant mass usually located in the pelvic cavity; (2) masses without an apparent organ-based primary site; (3) mild to moderate homogeneous or heterogeneous enhancement in solid area on enhanced CT; and (4) secondary manifestations, such as ascites, hepatic metastases, lymphadenopathy, hydronephrosis and hydroureter. The prognosis and overall survival rates were generally poor. Commonly used treatment strategies including aggressive tumor resection, polychemotherapy, and radiotherapy, showed various therapeutic effects. CT of DSRCT shows characteristic features that are helpful in diagnosis. Early discovery and complete resection, coupled with postoperative adjuvant chemotherapy, are important for prognosis of DSRCT. Whole abdominopelvic rather than locoregional radiotherapy is more effective for unresectable DSRCT.
PMCID: PMC4009557  PMID: 24803835
Desmoplastic small round cell tumor; Peritoneum; Pathology; Computed tomography; Clinical features
8.  Characteristics of Corn Stover Pretreated with Liquid Hot Water and Fed-Batch Semi-Simultaneous Saccharification and Fermentation for Bioethanol Production 
PLoS ONE  2014;9(4):e95455.
Corn stover is a promising feedstock for bioethanol production because of its abundant availability in China. To obtain higher ethanol concentration and higher ethanol yield, liquid hot water (LHW) pretreatment and fed-batch semi-simultaneous saccharification and fermentation (S-SSF) were used to enhance the enzymatic digestibility of corn stover and improve bioconversion of cellulose to ethanol. The results show that solid residues from LHW pretreatment of corn stover can be effectively converted into ethanol at severity factors ranging from 3.95 to 4.54, and the highest amount of xylan removed was approximately 89%. The ethanol concentrations of 38.4 g/L and 39.4 g/L as well as ethanol yields of 78.6% and 79.7% at severity factors of 3.95 and 4.54, respectively, were obtained by fed-batch S-SSF in an optimum conditions (initial substrate consistency of 10%, and 6.1% solid residues added into system at the prehydrolysis time of 6 h). The changes in surface morphological structure, specific surface area, pore volume and diameter of corn stover subjected to LHW process were also analyzed for interpreting the possible improvement mechanism.
PMCID: PMC3998958  PMID: 24763192
9.  Exosomes from Drug-Resistant Breast Cancer Cells Transmit Chemoresistance by a Horizontal Transfer of MicroRNAs 
PLoS ONE  2014;9(4):e95240.
Adriamycin and docetaxel are two agents commonly used in treatment of breast cancer, but their efficacy is often limited by the emergence of chemoresistance. Recent studies indicate that exosomes act as vehicles for exchange of genetic cargo between heterogeneous populations of tumor cells, engendering a transmitted drug resistance for cancer development and progression. However, the specific contribution of breast cancer-derived exosomes is poorly understood. Here we reinforced other's report that human breast cancer cell line MCF-7/S could acquire increased survival potential from its resistant variants MCF-7/Adr and MCF-7/Doc. Additionally, exosomes of the latter, A/exo and D/exo, significantly modulated the cell cycle distribution and drug-induced apoptosis with respect to S/exo. Exosomes pre-treated with RNase were unable to regulate cell cycle and apoptosis resistance, suggesting an RNA-dependent manner. Microarray and polymerase chain reaction for the miRNA expression profiles of A/exo, D/exo, and S/exo demonstrated that they loaded selective miRNA patterns. Following A/exo and D/exo transfer to recipient MCF-7/S, the same miRNAs were significantly increased in acquired cells. Target gene prediction and pathway analysis showed the involvement of miR-100, miR-222, and miR-30a in pathways implicated in cancer pathogenesis, membrane vesiculation and therapy failure. Furthermore, D/exo co-culture assays and miRNA mimics transfection experiments indicated that miR-222-rich D/exo could alter target gene expression in MCF-7/S. Our results suggest that drug-resistant breast cancer cells may spread resistance capacity to sensitive ones by releasing exosomes and that such effects could be partly attributed to the intercellular transfer of specific miRNAs.
PMCID: PMC3989268  PMID: 24740415
10.  Leptin Level and Oxidative Stress Contribute to Obesity-Induced Low Testosterone in Murine Testicular Tissue 
Objective. This study evaluated the effects of obesity on the function of reproductive organs in male mice and the possible mechanism of male secondary hypogonadism (SH) in obesity. Methods. Ninety-six mice were randomly assigned to three groups: the control group, diet-induced obesity group, and diet-induced obesity resistant group for 8 weeks and 19 weeks. The effects of short- and long-term high-fat diet on the reproductive organs were determined by measuring sperm count and motility, relative testis weight, testosterone level, pathological changes and apoptosis of Leydig cells. Oxidative stress was evaluated by determining malondialdehyde, H2O2, NO levels, and GSH in testis tissues. CAT, SOD, GSH-Px and Nrf2 mRNA were measured by real-time PCR. Results. Short- and long-term high-fat diet decreased sperm count and motility, relative testis weight, testosterone level; decreased CAT, SOD, GSH-Px and Nrf2 mRNA expression; increased MDA, H2O2, NO and leptin levels; inhibited the activity of CAT and GSH-Px enzymes. Pathological injury and apoptosis of Leydig cells were found in testis tissue. Conclusions. Pathological damage of Leydig cells, oxidative stress in testis tissue, and high level of leptin may provide some evidence to clarify the mechanisms of male SH in obesity.
PMCID: PMC4009340  PMID: 24829619
11.  miRNA 17 Family Regulates Cisplatin-Resistant and Metastasis by Targeting TGFbetaR2 in NSCLC 
PLoS ONE  2014;9(4):e94639.
MicroRNAs (miRNAs) have been proven to play crucial roles in cancer, including tumor chemotherapy resistance and metastasis of non-small-cell lung cancer (NSCLC). TGFβ signal pathway abnormality is widely found in cancer and correlates with tumor proliferation, apoptosis and metastasis. Here, miR-17, 20a, 20b were detected down-regulated in A549/DDP cells (cisplatin resistance) compared with A549 cells (cisplatin sensitive). Over-expression of miR-17, 20a, 20b can not only decrease cisplatin-resistant but also reduce migration by inhibiting epithelial-to-mesenchymal transition (EMT) in A549/DDP cells. These functions of miR-17, 20a, 20b may be caused at least in part via inhibition of TGFβ signal pathway, as miR-17, 20a, 20b are shown to directly target and repress TGF-beta receptor 2 (TGFβR2) which is an important component of TGFβ signal pathway. Consequently, our study suggests that miRNA 17 family (including miR-17, 20a, 20b) can act as TGFβR2 suppressor for reversing cisplatin-resistant and suppressing metastasis in NSCLC.
PMCID: PMC3983236  PMID: 24722426
12.  Morphology, Molecular Genetics, and Bioacoustics Support Two New Sympatric Xenophrys Toads (Amphibia: Anura: Megophryidae) in Southeast China 
PLoS ONE  2014;9(4):e93075.
Given their recent worldwide declines and extinctions, characterization of species-level diversity is of critical importance for large-scale biodiversity assessments and conservation of amphibians. This task is made difficult by the existence of cryptic species complexes, species groups comprising closely related and morphologically analogous species. The combination of morphology, genetic, and bioacoustic analyses permits robust and accurate species identification. Using these methods, we discovered two undescribed Xenophrys species, namely Xenophrys lini sp. nov. and Xenophrys cheni sp. nov. from the middle range of Luoxiao Mountains, southeast China. These two new species can be reliably distinguished from other known congeners by morphological and morphometric differences, distinctness in male advertisement calls, and substantial genetic distances (>3.6%) based on the mitochondrial 16s and 12s rRNA genes. The two new species, together with X. jinggangensis, are sympatric in the middle range of Luoxiao Mountains but may be isolated altitudinally and ecologically. Our study provides a first step to help resolve previously unrecognized cryptic biodiversity and provides insights into the understanding of Xenophrys diversification in the mountain complexes of southeast China.
PMCID: PMC3979665  PMID: 24714161
13.  Single Nucleotide Polymorphisms of MicroRNA Processing Machinery Genes and Outcome of Hepatocellular Carcinoma 
PLoS ONE  2014;9(3):e92791.
MicroRNA (miRNA)-related single nucleotide polymorphisms (miR-SNPs) can affect cancer development, treatment efficacy and patients prognosis. We examined 6 miR-SNPs in miRNA processing machinery genes including exportin 5 (XPO5) (rs11077), Ran-GTPase (RAN) (rs14035), Dicer (rs3742330), Trinucleotide Repeat Containing 6B (TNRC6B) (rs9623117), GEMIN3 (rs197412), GEMIN4 (rs2740348) in 108 surgically resected HCC patients and evaluated the impact of these miR-SNPs on HCC outcome. Among the 6 SNPs, only the A/A genotype of rs11077 located in XPO5 3′UTR was identified to associated independently with worse survival in HCC patients by multivariate analysis with relative risk, 0.395; 95% CI, 0.167–0.933; p = 0.034. This is the first study reporting that polymorphisms related to miRSNPs have prognostic value in hepatocellular carcinoma and identify the A/A genotype of rs11077 SNP site located in XPO5 3′UTR can help to predict worse prognosis in patients.
PMCID: PMC3968016  PMID: 24676133
14.  Regulation of transplanted mesenchymal stem cells by the lung progenitor niche in rats with chronic obstructive pulmonary disease 
Respiratory Research  2014;15(1):33.
Stem cell transplantation is a promising method for the treatment of chronic obstructive pulmonary disease (COPD), and mesenchymal stem cells (MSCs) have clinical potential for lung repair/regeneration. However, the rates of engraftment and differentiation are generally low following MSC therapy for lung injury. In previous studies, we constructed a pulmonary surfactant-associated protein A (SPA) suicide gene system, rAAV-SPA-TK, which induced apoptosis in alveolar epithelial type II (AT II) cells and vacated the AT II cell niche. We hypothesized that this system would increase the rates of MSC engraftment and repair in COPD rats.
The MSC engraftment rate and morphometric changes in lung tissue in vivo were investigated by in situ hybridization, hematoxylin and eosin staining, Masson’s trichrome staining, immunohistochemistry, and real-time PCR. The expression of hypoxia inducible factor (HIF-1α) and stromal cell-derived factor-1 (SDF-1), and relationship between HIF-1α and SDF-1 in a hypoxic cell model were analyzed by real-time PCR, western blotting, and enzyme-linked immunosorbent assay.
rAAV-SPA-TK transfection increased the recruitment of MSCs but induced pulmonary fibrosis in COPD rats. HIF-1α and SDF-1 expression were enhanced after rAAV-SPA-TK transfection. Hypoxia increased the expression of HIF-1α and SDF-1 in the hypoxic cell model, and SDF-1 expression was augmented by HIF-1α under hypoxic conditions.
Vacant AT II cell niches increase the homing and recruitment of MSCs to the lung in COPD rats. MSCs play an important role in lung repair and promote collagen fiber deposition after induction of secondary damage in AT II cells by rAAV-SPA-TK, which involves HIF-1α and SDF-1 signaling.
PMCID: PMC3987841  PMID: 24661402
Chronic obstructive pulmonary disease; Mesenchymal stem cells; Alveolar epithelial type II cells; Niche
15.  Integrated Chassis Control of Active Front Steering and Yaw Stability Control Based on Improved Inverse Nyquist Array Method 
The Scientific World Journal  2014;2014:919847.
An integrated chassis control (ICC) system with active front steering (AFS) and yaw stability control (YSC) is introduced in this paper. The proposed ICC algorithm uses the improved Inverse Nyquist Array (INA) method based on a 2-degree-of-freedom (DOF) planar vehicle reference model to decouple the plant dynamics under different frequency bands, and the change of velocity and cornering stiffness were considered to calculate the analytical solution in the precompensator design so that the INA based algorithm runs well and fast on the nonlinear vehicle system. The stability of the system is guaranteed by dynamic compensator together with a proposed PI feedback controller. After the response analysis of the system on frequency domain and time domain, simulations under step steering maneuver were carried out using a 2-DOF vehicle model and a 14-DOF vehicle model by Matlab/Simulink. The results show that the system is decoupled and the vehicle handling and stability performance are significantly improved by the proposed method.
PMCID: PMC3980790  PMID: 24782676
16.  RNA-seq reveals determinants of sensitivity to chemotherapy drugs in esophageal carcinoma cells 
Chemotherapy remains the mainstay of treatment for patients with incurable disease of esophageal carcinoma. Most patients respond poorly to chemotherapy, it is necessary to figure out biomarkers for chemotherapy sensitivity or resistance to perform the individualized therapy. In present work, the sensitivities of two ESCC cell lines to 9 chemotherapy drugs were identified and the transcriptome of these two cell lines were investigated by RNA-seq, the correlation between the sensitivity to drugs and expression of some genes was attempted to construct. Eca-1 was more resistant to most of the chemotherapy drugs than Eca-109 cell line. RNA-seq results showed that there is dramatic difference in the basal expression between these two ESCC cell lines. Pathway analysis demonstrated that these differentially expressed genes were mainly enriched in Gαi signaling, calcium signaling, cAMP-mediated signaling, G-protein coupled receptor signaling and actin cytoskeleton signaling pathways. The molecules in Gαi signaling (ADCY1 and SSTR3) and actin cytoskeleton signaling (MYH6 and MYH7) were highly expressed in multidrug-resistant Eca-1 cells, which were validated by quantitative PCR. Activation of these two pathways results in the upregulation of downstream signaling, PKA signaling and Src-STAT3, and downregulation of RAF-ERK signaling, which was validated by immunoblotting experiments. Our work proposed that activation of Gαi signaling or actin cytoskeleton signaling may confer ESCC cells resistance to most chemotherapy drugs. Our work might provide potential biomarkers and therapeutic targets for treatment of EC patients.
PMCID: PMC4014232  PMID: 24817948
Esophageal carcinoma; chemotherapy drugs; RNA-seq; pathway analysis
17.  Differences in the adsorption of enzymes onto lignins from diverse types of lignocellulosic biomass and the underlying mechanism 
Non-productive cellulase adsorption onto lignin has always been deemed to negatively affect the enzymatic hydrolysis of lignocellulosic feedstocks. Therefore, understanding enzyme-lignin interactions is essential for the development of enzyme mixtures, the processes of lignocellulose hydrolysis, and the genetic modification of lignocellulosic biomass and enzymes. In this work, we examined the properties of six lignins from diverse types of lignocellulosic biomass (aspen, pine, corn stover, kenaf, and two Arabidopsis lines, wild-type and SALK mutant of fah1) to determine the mechanism of differences in their adsorption of enzymes.
We found that lignin sources affected enzyme adsorption using structural features, such as functional groups and lignin composition. Guaiacyl (G) lignin had a higher adsorption capacity on enzymes than syringyl (S) lignin. The low S/G ratio and high uniform lignin fragment size had good correlations with high adsorption capacity. A higher content of phenolic hydroxyl groups and a lower content of carboxylic acid groups resulted in stronger adsorption affinity for corn stover lignin (CL) than for kenaf lignin (KL) and aspen lignin (AL). The lower amount of aliphatic hydroxyls that reduced hydrophobic interactions could explain the higher adsorption capacity of pine lignin (PL) than CL. Enzyme activity assays, as well as the hydrolysis of Avicel, phosphoric acid-swollen cellulose (PASC), and holocellulose, were performed to study the behaviors of mono-component enzymes that resulted in adsorption. We found that cellobiohydrolase (CBH) and xylanase were adsorbed the most by all lignins, endoglucanase (EG) showed less inhibition, and β-glucosidase (BG) was the least affected by lignins, indicating the important role of carbohydrate-binding module (CBM) in protein adsorption.
Lignin sources affect enzyme adsorption using structural features and lignin composition, such as S/G ratio, carboxylic acid, aliphatic hydroxyl, and phenolic hydroxyl. For mono-component enzymes, the adsorption capacity decreased in the order CBH, xylanase > EG > BG. These investigations revealed the difference in lignin properties between diverse biomass and adsorption capacity of enzymes to lignins, and the possible underlying mechanism. The results can also serve as a reference for the genetic modification of lignocellulosic biomass and enzymes.
PMCID: PMC3995585  PMID: 24624960
Enzyme adsorption; Diverse types of biomass; Lignin property; S/G ratio
18.  Enhancing Production of Alkaline Polygalacturonate Lyase from Bacillus subtilis by Fed-Batch Fermentation 
PLoS ONE  2014;9(3):e90392.
Alkaline polygalacturonate lyase (PGL, EC is an enzyme used in many industries. We developed a fed-batch fermentation process that combines the enzymatic pretreatment of the carbon source with controlling the pH of the fermentative broth to enhance the PGL production from Bacillus subtilis 7-3-3 to decrease the production cost. Maintaining the fermentation broth at pH 6.5 prior to feeding with ammonia and at pH 6.0 after feeding significantly improved PGL activity (743.5 U mL−1) compared with the control (202.5 U mL−1). The average PGL productivity reached 19.6 U mL−1 h−1 after 38 h of fermentation. The crude PGL was suitable for environmentally friendly ramie enzymatic degumming.
PMCID: PMC3946182  PMID: 24603713
19.  Minutiae Matching with Privacy Protection Based on the Combination of Garbled Circuit and Homomorphic Encryption 
The Scientific World Journal  2014;2014:525387.
Biometrics plays an important role in authentication applications since they are strongly linked to holders. With an increasing growth of e-commerce and e-government, one can expect that biometric-based authentication systems are possibly deployed over the open networks in the near future. However, due to its openness, the Internet poses a great challenge to the security and privacy of biometric authentication. Biometric data cannot be revoked, so it is of paramount importance that biometric data should be handled in a secure way. In this paper we present a scheme achieving privacy-preserving fingerprint authentication between two parties, in which fingerprint minutiae matching algorithm is completed in the encrypted domain. To improve the efficiency, we exploit homomorphic encryption as well as garbled circuits to design the protocol. Our goal is to provide protection for the security of template in storage and data privacy of two parties in transaction. The experimental results show that the proposed authentication protocol runs efficiently. Therefore, the protocol can run over open networks and help to alleviate the concerns on security and privacy of biometric applications over the open networks.
PMCID: PMC3953427  PMID: 24711729
20.  Muscovy duck reovirus p10.8 protein localizes to the nucleus via a nonconventional nuclear localization signal 
Virology Journal  2014;11:37.
It was previously report that the first open reading frame of Muscovy duck reocvirus S4 gene encodes a 95-amino-acid protein, designed p10.8, which has no sequence similarity to other known proteins. Its amino acid sequence offers no clues about its function.
Subcellular localization and nuclear import signal of p10.8 were characterized. We found that p10.8 protein localizes to the nucleus of infected and transfected cells, suggesting that p10.8 nuclear localization is not facilitated by viral infection or any other viral protein. A functional non-canonical nuclear localization signal (NLS) for p10.8 was identified and mapped to N-terminus residues 1–40. The NLS has the ability to retarget a large cytoplasmic protein to the nucleus.
p10.8 imported into the nucleus might via a nonconventional signal nuclear signal.
PMCID: PMC4015296  PMID: 24564937
Muscovy duck reocvirus; p10.8 protein; Nuclear localization signal
21.  A Novel Mutation in the TECTA Gene in a Chinese Family with Autosomal Dominant Nonsyndromic Hearing Loss 
PLoS ONE  2014;9(2):e89240.
TECTA-related deafness can be inherited as autosomal-dominant nonsyndromic deafness (designated DFNA) or as the autosomal-recessive version. The α-tectorin protein, which is encoded by the TECTA gene, is one of the major components of the tectorial membrane in the inner ear. Using targeted DNA capture and massively parallel sequencing (MPS), we screened 42 genes known to be responsible for human deafness in a Chinese family (Family 3187) in which common deafness mutations had been ruled out as the cause, and identified a novel mutation, c.257–262CCTTTC>GCT (p. Ser86Cys; p. Pro88del) in exon 3 of the TECTA gene in the proband and his extended family. All affected individuals in this family had moderate down-sloping hearing loss across all frequencies. To our knowledge, this is the second TECTA mutation identified in Chinese population. This study demonstrates that targeted genomic capture, MPS, and barcode technology might broaden the availability of genetic testing for individuals with undiagnosed DFNA.
PMCID: PMC3931719  PMID: 24586623
22.  Transjugular intrahepatic portosystemic shunt with covered stents for hepatocellular carcinoma with portal vein tumor thrombosis 
AIM: To evaluate transjugular intrahepatic portosystemic shunt (TIPS) with covered stents for hepatocellular carcinoma (HCC) with main portal vein tumor thrombus (PVTT).
METHODS: Eleven advanced HCC patients (all male, aged 37-78 years, mean: 54.3 ± 12.7 years) presented with acute massive upper gastrointestinal bleeding (n = 9) or refractory ascites (n = 2) due to tumor thrombus in the main portal vein. The diagnosis of PVTT was based on contrast-enhanced computed tomography and color Doppler sonography. The patients underwent TIPS with covered stents. Clinical characteristics and average survival time of 11 patients were analyzed. Portal vein pressure was assessed before and after TIPS. The follow-up period was 2-18 mo.
RESULTS: TIPS with covered stents was successfully completed in all 11 patients. The mean portal vein pressure was reduced from 32.0 to 11.8 mmHg (t = 10.756, P = 0.000). Gastrointestinal bleeding was stopped in nine patients. Refractory ascites completely disappeared in one patient and was alleviated in another. Hepatic encephalopathy was observed in six patients and was resolved with drug therapy. During the follow-up, ultrasound indicated the patency of the shunt and there was no recurrence of symptoms. Death occurred 2-14 mo (mean: 5.67 mo) after TIPS in nine cases, which were all due to multiple organ failure. In the remaining two cases, the patients were still alive at the 16- and 18-mo follow-up, respectively.
CONCLUSION: TIPS with covered stents for HCC patients with tumor thrombus in the main portal vein is technically feasible, and short-term efficacy is favorable.
PMCID: PMC3925870  PMID: 24587637
Transjugular intrahepatic portosystemic shunt; Covered stent; Portal hypertension; Main portal vein tumor thrombus; Hepatocellular carcinoma
23.  A Genetic Variant in Vitamin B12 Metabolic Genes That Reduces the Risk of Congenital Heart Disease in Han Chinese Populations 
PLoS ONE  2014;9(2):e88332.
Genome-wide association studies on components of the one-carbon metabolic pathway revealed that human vitamin B12 levels could be significantly influenced by variationsinthefucosyltransferase 2 (FUT2), cubilin (CUBN), and transcobalamin-I (TCN1) genes. An altered vitamin B12 level is an important factor that disturbs the homeostasis of the folate metabolism pathway, which in turn can potentially lead to the development of congenital heart disease (CHD). Therefore, we investigated the association between the variants of vitamin B12-related genes and CHD in Han Chinese populations.
Methods and Results
Six variants of the vitamin B12-related genes were selected for analysis in two independent case-control studies, with a total of 868 CHD patients and 931 controls. The variant rs11254363 of the CUBN gene was associated with a decreased risk of developing CHD in both the separate and combined case-control studies. Combined samples from the two cohorts had a significant decrease in CHD risk for the G allele (OR = 0.48, P = 1.7×10−5) and AG+GG genotypes (OR = 0.49, P = 4×10−5), compared with the wild-type A allele and AA genotype, respectively.
Considering the G allele of variant rs11254363 of the CUBN gene was associated with an increased level of circulating vitamin B12. This result suggested that the carriers of the G allele would benefit from the protection offered by the high vitamin B12 concentration during critical heart development stages. This finding shed light on the unexpected role of CUBN in CHD development and highlighted the interplay of diet, genetics, and human birth defects.
PMCID: PMC3922769  PMID: 24533076
24.  A functional variant in the cystathionine β-synthase gene promoter significantly reduces congenital heart disease susceptibility in a Han Chinese population 
Cell Research  2012;23(2):242-253.
Homocysteine is an independent risk factor for various cardiovascular diseases. There are two ways to remove homocysteine from embryonic cardiac cells: remethylation to form methionine or transsulfuration to form cysteine. Cystathionine β-synthase (CBS) catalyzes the first step of homocysteine transsulfuration as a rate-limiting enzyme. In this study, we identified a functional variant −4673C>G (rs2850144) in the CBS gene promoter region that significantly reduces the susceptibility to congenital heart disease (CHD) in a Han Chinese population consisting of 2 340 CHD patients and 2 270 controls. Individuals carrying the heterozygous CG and homozygous GG genotypes had a 15% (odds ratio (OR) = 0.85, 95% confidence interval (CI) = 0.75-0.96, P = 0.011) and 40% (OR = 0.60, 95% CI = 0.49-0.73, P = 1.78 × 10−7) reduced risk to develop CHD than the wild-type CC genotype carriers in the combined samples, respectively. Additional stratified analyses demonstrated that CBS −4673C>G is significantly related to septation defects and conotruncal defects. In vivo detection of CBS mRNA levels in human cardiac tissues and in vitro luciferase assays consistently showed that the minor G allele significantly increased CBS transcription. A functional analysis revealed that both the attenuated transcription suppressor SP1 binding affinity and the CBS promoter hypomethylation specifically linked with the minor G allele contributed to the remarkably upregulated CBS expression. Consequently, the carriers with genetically increased CBS expression would benefit from the protection due to the low homocysteine levels maintained by CBS in certain cells during the critical heart development stages. These results shed light on unexpected role of CBS and highlight the importance of homocysteine removal in cardiac development.
PMCID: PMC3567826  PMID: 22986502
congenital heart disease; cystathionine β-synthase; non-coding variant; homocysteine
25.  A long noncoding RNA contributes to neuropathic pain by silencing Kcna2 in primary afferent neurons 
Nature neuroscience  2013;16(8):1024-1031.
Neuropathic pain is a refractory disease characterized by maladaptive changes in gene transcription and translation within the sensory pathway. Long noncoding RNAs (lncRNAs) are emerging as new players in gene regulation, but how lncRNAs operate in the development of neuropathic pain is unclear. Here we identify a conserved lncRNA for Kcna2 (named Kcna2 antisense RNA) in first-order sensory neurons of rat dorsal root ganglion (DRG). Peripheral nerve injury increases Kcna2 antisense RNA expression in injured DRG through activation of myeloid zinc finger protein 1, a transcription factor that binds to Kcna2 antisense RNA gene promoter. Mimicking this increase downregulates Kcna2, reduces total Kv current, increases excitability in DRG neurons, and produces neuropathic pain symptoms. Blocking this increase reverses nerve injury-induced downregulation of DRG Kcna2 and attenuates development and maintenance of neuropathic pain. These findings suggest native Kcna2 antisense RNA as a new therapeutic target for the treatment of neuropathic pain.
PMCID: PMC3742386  PMID: 23792947

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