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1.  Identification and Whole-Genome Sequence Analysis of Tembusu Virus GX2013G, Isolated from a Cherry Valley Duckling in Southern China 
Genome Announcements  2015;3(1):e00007-15.
A duck tembusu virus (DTMUV) was isolated from the brain of a Cherry Valley duckling that showed neurological signs by using a specific-pathogen-free chicken embryo. The isolate was named GX2013G (GenBank accession no. KM275941). The strain GX2013G was identified with reverse transcription-PCR (RT-PCR), and the amplicon was sequenced. The genome that was obtained is 10,990 nucleotides in length and contains a single open reading frame encoding a putative polyprotein of 3,425 amino acids. This study will advance the understanding of the epidemiology and molecular characteristics of tembusu virus (TMUV) in Guangxi and further studies of the mechanisms of virus replication and pathogenesis.
PMCID: PMC4335318
2.  Visualization of arrestin recruitment by a G Protein-Coupled Receptor 
Nature  2014;512(7513):218-222.
G Protein Coupled Receptors (GPCRs) are critically regulated by β-arrestins (βarrs), which not only desensitize G protein signaling but also initiate a G protein independent wave of signaling1-5. A recent surge of structural data on a number of GPCRs, including the β2 adrenergic receptor (β2AR)-G protein complex, has provided novel insights into the structural basis of receptor activation6-11. Lacking however has been complementary information on recruitment of βarrs to activated GPCRs primarily due to challenges in obtaining stable receptor-βarr complexes for structural studies. Here, we devised a strategy for forming and purifying a functional β2AR-βarr1 complex that allowed us to visualize its architecture by single particle negative stain electron microscopy (EM) and to characterize the interactions between β2AR and βarr1 using hydrogen-deuterium exchange mass spectrometry (HDXMS) and chemical cross-linking. EM 2D averages and 3D reconstructions reveal bimodal binding of βarr1 to the β2AR, involving two separate sets of interactions, one with the phosphorylated carboxy-terminus of the receptor and the other with its seven-transmembrane core. Areas of reduced HDX together with identification of cross-linked residues suggest engagement of the finger loop of βarr1 with the seven-transmembrane core of the receptor. In contrast, focal areas of increased HDX indicate regions of increased dynamics in both N and C domains of βarr1 when coupled to the β2AR. A molecular model of the β2AR-βarr signaling complex was made by docking activated βarr1 and β2AR crystal structures into the EM map densities with constraints provided by HDXMS and cross-linking, allowing us to obtain valuable insights into the overall architecture of a receptor-arrestin complex. The dynamic and structural information presented herein provides a framework for better understanding the basis of GPCR regulation by arrestins.
PMCID: PMC4134437  PMID: 25043026
3.  A duplex real-time PCR assay for the detection and quantification of avian reovirus and Mycoplasma synoviae 
Virology Journal  2015;12:22.
Infectious arthritis in broilers represents an economic and health problem, resulting in severe losses due to retarded growth and downgrading at the slaughterhouse. The most common agents associated with cases of infectious arthritis in poultry are avian reovirus (ARV) and Mycoplasma synoviae (MS). The accurate differentiation and rapid diagnosis of ARV and MS are essential prerequisites for the effective control and prevention of these avian pathogens in poultry flocks. This study thus aimed to develop and validate a duplex real-time PCR assay for the simultaneous detection and quantification of ARV and MS.
Specific primers and probes for each pathogen were designed to target the special sequence of the ARV σC gene or the MS phase-variable surface lipoprotein hemagglutinin (vlhA) gene. A duplex real-time PCR assay was developed, and the reaction conditions were optimized for the rapid detection and quantification of ARV and MS.
The duplex real-time PCR assay was capable of ARV- and MS-specific detection without cross-reaction with other non-targeted avian pathogens. The sensitivity of this assay was 2 × 101 copies for a recombinant plasmid containing ARV σC or MS vlhA gene, and 100 times higher than that of conventional PCR. This newly developed PCR assay was also reproducible and stable. All tested field samples of ARV and/or MS were detectable with this duplex real-time PCR assay compared with pathogen isolation and identification as well as serological tests.
This duplex real-time PCR assay is highly specific, sensitive and reproducible and thus could provide a rapid, specific and sensitive diagnostic tool for the simultaneous detection of ARV and MS in poultry flocks. The assay will be useful not only for clinical diagnostics and disease surveillance but also for the efficient control and prevention of ARV and MS infections.
PMCID: PMC4335558
Duplex real-time PCR assay; Avian reovirus; Mycoplasma synoviae
4.  An immunohistochemical study of CD83- and CD1a-positive dendritic cells in the decidua of women with recurrent spontaneous abortion 
There are more and more women with recurrent spontaneous abortion (RSA). The mechanism of RSA is still unclear. Immunological factors have been postulated to play a role in the etiology of RSA. Dendritic cells (DCs) are the most potent antigen-presenting cells in the immune system, and the decidual DCs may take part in the occurrence of RSA. The difference in maturity status of decidual DCs among women with RSA and women with normal pregnancies is worthy of studying for its application to prevention and therapy.
The EnVision two-step immunohistochemical staining technique was used to detect the expression of CD83 and CD1a in the decidua of women with RSA (30 cases) and normal pregnancies (30 cases). The maturity status, distribution and quantity of DCs in the two groups were observed. Observation of the staining and cell counting were done using microscope within 30 randomly selected high-power fields (HPF, 40 × 10). All data analyses were conducted with SPSS 17.0 and the statistical significance was set at P <0.05.
The decidua from the two groups contained DCs that stained with the anti-CD83 and anti-CD1a antibody. Most of the decidual CD83+DCs from two groups were located in the stroma. There were more CD83+DCs clustered with other DCs in the stroma from women with RSA than normal pregnancies. Most of the CD1a+DCs in the decidua from the two groups are located close to maternal glandular epithelium. No difference in the location of CD1a+DCs was found in the decidua between two groups. The number of decidual CD83+DCs was statistically significantly higher in RSA women than in normal early pregnant women (14.20 ± 13.34/30 HPF versus 4.77 ± 2.64/30 HPF; t = 3.800, P = 0.001). The number of CD1a+DCs in the decidua was statistically significantly lower in RSA women compared with normal early pregnant women (3.97 ± 3.75/30 HPF versus 7.60 ± 6.08/30 HPF; t = 2.786, P = 0.008).
These findings suggest that the increase in the number of mature DCs and the decrease in the quantity of immature DCs in the decidua may be related to RSA. The maturation of decidual DCs may play an important role in the pathogenesis of RSA.
PMCID: PMC4301856  PMID: 25563385
recurrent spontaneous abortion; decidua; dendritic cells; CD83; CD1a; immunohistochemistry
5.  Sulfolobus Replication Factor C Stimulates the Activity of DNA Polymerase B1 
Journal of Bacteriology  2014;196(13):2367-2375.
Replication factor C (RFC) is known to function in loading proliferating cell nuclear antigen (PCNA) onto primed DNA, allowing PCNA to tether DNA polymerase for highly processive DNA synthesis in eukaryotic and archaeal replication. In this report, we show that an RFC complex from the hyperthermophilic archaea of the genus Sulfolobus physically interacts with DNA polymerase B1 (PolB1) and enhances both the polymerase and 3′-5′ exonuclease activities of PolB1 in an ATP-independent manner. Stimulation of the PolB1 activity by RFC is independent of the ability of RFC to bind DNA but is consistent with the ability of RFC to facilitate DNA binding by PolB1 through protein-protein interaction. These results suggest that Sulfolobus RFC may play a role in recruiting DNA polymerase for efficient primer extension, in addition to clamp loading, during DNA replication.
PMCID: PMC4054168  PMID: 24748616
6.  T helper cell dysregulation with hepatitis B and rebalance with glucocorticoids 
World Journal of Gastroenterology : WJG  2014;20(48):18354-18359.
AIM: To investigate T helper 17/regulatory T cell alterations in early severe hepatitis B and the effect of glucocorticoids.
METHODS: The study included 20 patients in the early stage of severe hepatitis B (SHB) and 11 healthy controls. All patients had elevated T helper 17 (Th17) levels, decreased regulatory T (Treg) cell levels, and significant Th17/Treg ratios.
RESULTS: After glucocorticoid treatment, 16 patients showed improvement with significant decreases in Th17 levels, increases in Treg, and rebalanced Th17/Treg ratios. The four patients who showed no improvement had increases in both Th17 and Treg levels and an even higher Th17/Treg ratio than before.
CONCLUSION: Glucocorticoid treatment can rectify Th17/Treg dysregulation in patients with SHB.
PMCID: PMC4277972  PMID: 25561802
Severe hepatitis B; T helper 17 cell; Regulatory T cell; Dysregulation; Glucocorticoid
7.  Randomized trial of leuprolide versus continuous oral contraceptives in the treatment of endometriosis-associated pelvic pain 
Fertility and sterility  2011;95(5):1568-1573.
To compare the efficacy of leuprolide and continuous oral contraceptives in the treatment of endometriosis-associated pain.
Prospective, randomized, double-blind controlled trial.
Academic medical centers in Rochester, New York, and Boston, Massachusetts.
Forty-seven women with endometriosis-associated pelvic pain.
Forty-eight weeks of either depot leuprolide, 11.25 mg IM every 12 weeks with hormonal add-back using norethindrone acetate 5 mg orally, daily; or a generic monophasic oral contraceptive (1 mg norethindrone + 35 mg ethinyl estradiol) given daily.
Main Outcome Measure(s)
Biberoglu and Behrman (B&B) pain scores, numerical rating scores (NRS), Beck Depression Inventory (BDI), and Index of Sexual Satisfaction (ISS).
Based on enrollment of 47 women randomized to continuous oral contraceptives and to leuprolide, there were statistically significant declines in B&B, NRS, and BDI scores from baseline in both groups. There were no significant differences, however, in the extent of reduction in these measures between the groups.
Leuprolide and continuous oral contraceptives appear to be equally effective in the treatment of endometriosis-associated pelvic pain. (Fertil Steril 2011;95:1568–73. 2011 by American Society for Reproductive Medicine.)
PMCID: PMC4271794  PMID: 21300339
Endometriosis; pelvic pain; GnRH agonists; gonadotropin-releasing hormone agonist; oral contraceptives; randomized controlled trial
8.  Cross-Fostering Increases Th1/Th2 Expression in a Prenatal Dexamethasone Exposure Rat Model 
PLoS ONE  2014;9(12):e115554.
Prenatal dexamethasone exposure has been reported to increase allergy potential in childhood possibly by interference with normal immunological development in utero. This study investigated the effects of prenatal dexamethasone on T helper cell immune responses in a rat model.
Pregnant rats received either dexamethasone 0.1 mg/kg/day or normal saline from gestational day 14–21. Off-springs were cared for by their biological mother, or cross-fostered by the opposing group. Spleen and blood samples were collected at post-natal day 7 and 120 and tested for mRNA expression and plasma cytokine levels of Th1/Th2/Th17 immune response.
Both Th1 (T-bet) and Th2 (GATA-3) mRNA expression were shown to have a significant increase in the prenatal dexamethasone exposure group at day 120 (p<0.05). The plasma levels for Th1 (IFNγ and IL-2) and Th2 (IL-4, IL-5, IL-13) were found to have no significant differences between the two group (p>0.05). The mRNA expression of Th17 (RORγt) showed a significant decrease at post-natal day 120 as well as the plasma level of IL-17A at day 7 (11.21±1.67 vs. 6.23±1.06 pg/ml, p = 0.02). Cross-fostering by a dexamethasone exposed mother resulted in a significant increase in Th1/Th2 mRNA expression (p<0.05) and decrease of Th17.
Prenatal dexamethasone exposure increased Th1, Th2 and decreased Th17 expression. Cross-fostering by a dexamethasone exposed mother results in more prominent increase of Th1 and Th2 expression.
PMCID: PMC4272273  PMID: 25526616
9.  Repression of Zeb1 and Hypoxia Cause Sequential MET and Induction of Aid, Oct4, and Dnmt1, Leading to Immortalization and Multipotential Reprogramming of Fibroblasts in Spheres 
Stem cells (Dayton, Ohio)  2013;31(7):1350-1362.
Here, we demonstrate that sphere formation triggers immortalization and stable reprogramming of mouse fibroblasts. Cell contact signaling in spheres causes downregulation of the EMT transcription factor Zeb1 leading to rapid mesenchymal-to-epithelial transition. And, hypoxia within spheres together with loss of Zeb1 repression synergize to cause superinduction of Hif1a, which in turn leads to induction of the DNA demethylase Aid/Aicda, demethylation of the Oct4 promoter/enhancer and multipotency. Oct4 and Nanog expression diminish when cells are removed from the hypoxic environment of spheres and placed in monolayer culture, but the cells retain multipotential capacity, demonstrating stable reprogramming and a gene expression pattern resembling adult stem cells. Oct4 has been shown to induce Dnmt1 in mesenchymal stem cells, and we link Oct4 and Dnmt1 to silencing of cell cycle inhibitory cyclin dependent kinase inhibitors and Arf, and immortalization of the reprogrammed fibroblasts. Sphere formation then represents a novel and rapid protocol for immortalization and stable reprogramming of fibroblasts to multipotency that does not require exogenous expression of a stem cell factor or a lineage-specifying transcription factor.
PMCID: PMC4265806  PMID: 23554223
10.  Comparison of the effects of albumin and crystalloid on mortality in adult patients with severe sepsis and septic shock: a meta-analysis of randomized clinical trials 
Critical Care  2014;18(6):702.
The aim of this study was to examine whether albumin reduced mortality when employed for the resuscitation of adult patients with severe sepsis and septic shock compared with crystalloid by meta-analysis.
We searched for and gathered data from MEDLINE, Elsevier, Cochrane Central Register of Controlled Trials and Web of Science databases. Studies were eligible if they compared the effects of albumin versus crystalloid therapy on mortality in adult patients with severe sepsis and septic shock. Two reviewers extracted data independently. Disagreements were resolved by discussion with other two reviewers until a consensus was achieved. Data including mortality, sample size of the patients with severe sepsis, sample size of the patients with septic shock and resuscitation endpoints were extracted. Data were analyzed by the methods recommended by the Cochrane Collaboration Review Manager 4.2 software.
A total of 5,534 records were identified through the initial search. Five studies compared albumin with crystalloid. In total, 3,658 severe sepsis and 2,180 septic shock patients were included in the meta-analysis. The heterogeneity was determined to be non-significant (P = 0.86, I2 = 0%). Compared with crystalloid, a trend toward reduced 90-day mortality was observed in severe sepsis patients resuscitated with albumin (odds ratio (OR) 0.88; 95% CI, 0.76 to 1.01; P = 0.08). However, the use of albumin for resuscitation significantly decreased 90-day mortality in septic shock patients (OR 0.81; 95% CI, 0.67 to 0.97; P = 0.03). Compared with saline, the use of albumin for resuscitation slightly improved outcome in severe sepsis patients (OR 0.81; 95% CI, 0.64 to 1.08; P = 0.09).
In this meta-analysis, a trend toward reduced 90-day mortality was observed in severe sepsis patients resuscitated with albumin compared with crystalloid and saline. Moreover, the 90-day mortality of patients with septic shock decreased significantly.
Electronic supplementary material
The online version of this article (doi:10.1186/s13054-014-0702-y) contains supplementary material, which is available to authorized users.
PMCID: PMC4284920  PMID: 25499187
11.  Molecular Characterization of the Full Muscovy Duck Parvovirus, Isolated in Guangxi, China 
Genome Announcements  2014;2(6):e01249-14.
We report the complete genomic sequence of the full Muscovy duck parvovirus (MDPV) strain, designated GX2011-5, isolated from a Muscovy duck in Guangxi Province, China. The complete genomic sequence was 5,132 bp in length and contained two major open reading frames encoding a 1,844-nucleotide (nt) nonstructural protein and a 2,199-nt capsid protein. Comparison of the complete sequence of GX2011-5 with other published sequences of Muscovy duck parvovirus revealed that this strain exhibited 90.4% to 95.1% sequence homology. This report will advance our understanding of the epidemiology and molecular characteristics of MDPV in the Muscovy duck population in Guangxi, China.
PMCID: PMC4263826  PMID: 25502664
12.  Dynamics in the resistant and susceptible peanut (Arachis hypogaea L.) root transcriptome on infection with the Ralstonia solanacearum 
BMC Genomics  2014;15(1):1078.
Bacterial wilt caused by Ralstonia solanacearum is a serious soil-borne disease of peanut (Arachis hypogaea L). The molecular basis of peanut response to R. solanacearum remains unknown. To understand the resistance mechanism behind peanut resistance to R. solanacearum, we used RNA-Seq to perform global transcriptome profiling on the roots of peanut resistant (R) and susceptible (S) genotypes under R. solanacearum infection.
A total of 4.95 x 108 raw sequence reads were generated and subsequently assembled into 271, 790 unigenes with an average length of 890 bp and a N50 of 1, 665 bp. 179, 641 unigenes could be annotated by public protein databases. The pairwise transcriptome comparsions of time course (6, 12, 24, 48 and 72 h post inoculation) were conducted 1) between inoculated and control samples of each genotype, 2) between inoculated samples of R and S genotypes. The linear dynamics of transcriptome profile was observed between adjacent samples for each genotype, two genotypes shared similar transcriptome pattern at early time points with most significant up regulation at 12 hour, and samples from R genotype at 24 h and S genotype at 48 h showed similar transcriptome pattern, significant differences of transcriptional profile were observed in pairwise comparisons between R and S genotypes. KEGG analysis showed that the primary metabolisms were inhibited in both genotypes and stronger inhibition in R genotype post inoculation. The defense related genes (R gene, LRR-RLK, cell wall genes, etc.) generally showed a genotype-specific down regulation and different expression between both genotypes.
This transcriptome profiling provided the largest data set that explores the dynamic in crosstalk between peanut and R. solanacearum. The results suggested that the down-regulation of primary metabolism is contributed to the resistance difference between R and S genotypes. The genotype-specific expression pattern of defense related DEGs also contributed to the resistance difference between R and S genotype. This study will strongly contribute to better understand the molecular interaction between plant and R. solanacearum.
Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-1078) contains supplementary material, which is available to authorized users.
PMCID: PMC4300042  PMID: 25481772
Arachis hypogaea L; Ralstonia solanacearum; DEGs; RNA-seq
13.  Rapid Detection of New Delhi Metallo-β-Lactamase Gene and Variants Coding for Carbapenemases with Different Activities by Use of a PCR-Based In Vitro Protein Expression Method 
Journal of Clinical Microbiology  2014;52(6):1947-1953.
New Delhi metallo-β-lactamase (NDM)-producing bacteria are considered potential global health threats. It is necessary to monitor NDM-1 and its variants in clinical isolates in order to understand the NDM-1 epidemic and the impact of its variants on β-lactam resistance. To reduce the lengthy time needed for cloning and expression of NDM-1 variants, a novel PCR-based in vitro protein expression (PCR-P) method was used to detect blaNDM-1 and its variants coding for carbapenemases with different activities (functional variants). The PCR-P method combined a long-fragment real-time quantitative PCR (LF-qPCR) with in vitro cell-free expression to convert the blaNDM-1 amplicons into NDM for carbapenemase assay. The method could screen for blaNDM-1 within 3 h with a detection limit of 5 copies and identify functional variants within 1 day. Using the PCR-P to analyze 5 recent blaNDM-1 variants, 2 functional variants, blaNDM-4 and blaNDM-5, were revealed. In the initial testing of 23 clinical isolates, the PCR-P assay correctly found 8 isolates containing blaNDM-1. This novel method provides the first integrated approach for rapidly detecting the full-length blaNDM-1 and revealing its functional variants in clinical isolates.
PMCID: PMC4042754  PMID: 24671780
14.  Correlating Microbial Diversity Patterns with Geochemistry in an Extreme and Heterogeneous Environment of Mine Tailings 
Applied and Environmental Microbiology  2014;80(12):3677-3686.
Recent molecular surveys have advanced our understanding of the forces shaping the large-scale ecological distribution of microbes in Earth's extreme habitats, such as hot springs and acid mine drainage. However, few investigations have attempted dense spatial analyses of specific sites to resolve the local diversity of these extraordinary organisms and how communities are shaped by the harsh environmental conditions found there. We have applied a 16S rRNA gene-targeted 454 pyrosequencing approach to explore the phylogenetic differentiation among 90 microbial communities from a massive copper tailing impoundment generating acidic drainage and coupled these variations in community composition with geochemical parameters to reveal ecological interactions in this extreme environment. Our data showed that the overall microbial diversity estimates and relative abundances of most of the dominant lineages were significantly correlated with pH, with the simplest assemblages occurring under extremely acidic conditions and more diverse assemblages associated with neutral pHs. The consistent shifts in community composition along the pH gradient indicated that different taxa were involved in the different acidification stages of the mine tailings. Moreover, the effect of pH in shaping phylogenetic structure within specific lineages was also clearly evident, although the phylogenetic differentiations within the Alphaproteobacteria, Deltaproteobacteria, and Firmicutes were attributed to variations in ferric and ferrous iron concentrations. Application of the microbial assemblage prediction model further supported pH as the major factor driving community structure and demonstrated that several of the major lineages are readily predictable. Together, these results suggest that pH is primarily responsible for structuring whole communities in the extreme and heterogeneous mine tailings, although the diverse microbial taxa may respond differently to various environmental conditions.
PMCID: PMC4054149  PMID: 24727268
15.  Inhibitory Effect of b-AP15 on the 20S Proteasome 
Biomolecules  2014;4(4):931-939.
The 26S proteasome is a cellular proteolytic complex containing 19S regulatory particles and the 20S core proteasome. It was reported that the small molecule b-AP15 targets the proteasome by inhibiting deubiquitination of the 19S regulatory particles of the proteasome complex. An investigation of b-AP15 on the 20S proteasome core suggested that this compound can also inhibit the 20S proteasome with a potency equivalent to that found to inhibit the 19S regulatory particles.
PMCID: PMC4279163  PMID: 25317846
proteasome inhibitor; b-AP15; 19S regulatory particles
16.  Long-Term Effects of Maternal Citrulline Supplementation on Renal Transcriptome Prevention of Nitric Oxide Depletion-Related Programmed Hypertension: The Impact of Gene-Nutrient Interactions 
Maternal malnutrition can elicit gene expression leading to fetal programming. l-citrulline (CIT) can be converted to l-arginine to generate nitric oxide (NO). We examined whether maternal CIT supplementation can prevent NG-nitro-l-arginine-methyl ester (l-NAME, NO synthase inhibitor)-induced programmed hypertension and examined their effects on the renal transcriptome in male offspring using next generation RNA sequencing (RNA-Seq) technology. Pregnant Sprague-Dawley rats received l-NAME administration at 60mg/kg/day subcutaneously via osmotic minipump during pregnancy alone or with additional 0.25% l-citrulline solution in drinking water during the whole period of pregnancy and lactation. Male offspring were assigned to three groups: control, l-NAME, and l-NAME + CIT. l-NAME exposure induced hypertension in the 12-week-old offspring, which CIT therapy prevented. Identified differentially expressed genes in l-NAME and CIT-treated offspring kidneys, including Guca2b, Hmox1, Hba2, Hba-a2, Dusp1, and Serpine1 are related to regulation of blood pressure (BP) and oxidative stress. In conclusion, our data suggests that the beneficial effects of CIT supplementation are attributed to alterations in expression levels of genes related to BP control and oxidative stress. Our results suggest that early nutritional intervention by CIT has long-term impact on the renal transcriptome to prevent NO depletion-related programmed hypertension. However, our RNA-Seq results might be a secondary phenomenon. The implications of epigenetic regulation at an early stage of programming deserve further clarification.
PMCID: PMC4284764  PMID: 25517031
citrulline; developmental programming; epigenetic regulation; hypertension; next generation sequencing; nitric oxide
17.  Afatinib circumvents multidrug resistance via dually inhibiting ATP binding cassette subfamily G member 2 in vitro and in vivo 
Oncotarget  2014;5(23):11971-11985.
Multidrug resistance (MDR) to chemotherapeutic drugs is a formidable barrier to the success of cancer chemotherapy. Expressions of ATP-binding cassette (ABC) transporters contribute to clinical MDR phenotype. In this study, we found that afatinib, a small molecule tyrosine kinase inhibitor (TKI) targeting EGFR, HER-2 and HER-4, reversed the chemoresistance mediated by ABCG2 in vitro, but had no effect on that mediated by multidrug resistance protein ABCB1 and ABCC1. In addition, afatinib, in combination with topotecan, significantly inhibited the growth of ABCG2-overexpressing cell xenograft tumors in vivo. Mechanistic investigations exhibited that afatinib significantly inhibited ATPase activity of ABCG2 and downregulated expression level of ABCG2, which resulted in the suppression of efflux activity of ABCG2 in parallel to the increase of intracellular accumulation of ABCG2 substrate anticancer agents. Taken together, our findings may provide a new and useful combinational therapeutic strategy of afatinib with chemotherapeutical drug for the patients with ABCG2 overexpressing cancer cells.
PMCID: PMC4322967  PMID: 25436978
Multidrug resistance; ABCG2; tyrosine kinase inhibitor; afatinib; combined chemotherapy
18.  The Novel Small Leucine-Rich Repeat Protein Podocan is a Negative Regulator of Migration and Proliferation of Smooth Muscle Cells, Modulates Neointima Formation and is Expressed in Human Atheroma 
Circulation  2013;128(22):2351-2363.
SMC migration and proliferation critically influence the clinical course of vascular disease. We tested the effect of the novel small leucine-rich repeat protein podocan on SMC migration and proliferation using a podocan deficient mouse in combination with a model of arterial injury and aortic explant SMC culture. In addition, we examined the effect of overexpression of the human form of podocan on human SMC and tested for podocan expression in human atherosclerosis. In all these conditions we evaluated concomitantly the Wnt-TCF-pathway.
Methods and Results
Podocan was strongly and selectively expressed in arteries of WT mice after injury. Podocan−/− mice showed increased arterial lesion formation as compared to WT littermates in response to injury (P<0.05). Also, SMC proliferation was increased in arteries of podocan −/− mice compared to WT (P<0.05). In vitro, migration and proliferation were increased in podocan−/− SMC and were normalized by transfection with the WT podocan gene (P<0.05). In addition, upregulation of the Wnt-TCF-pathway was found in SMC of podocan−/− mice both in vitro and in vivo. On the other hand, podocan overexpression in human SMC significantly reduced SMC migration and proliferation inhibiting the Wnt-TCF-pathway. Podocan and a Wnt-TCF-pathway marker were differently expressed in human coronary restenotic versus primary lesions.
Podocan appears to be a potent negative regulator of the migration and proliferation of both murine and human SMC. The lack of podocan results in excessive arterial repair and prolonged SMC proliferation, which likely is mediated by the Wnt-TCF-pathway.
PMCID: PMC3917564  PMID: 24043300
Extracellular Matrix; Smooth Muscle Cells; Proliferation; Arteries
19.  Triggers of suicide ideation and protective factors of actually executing suicide among first onset cases in older psychiatric outpatients: a qualitative study 
BMC Psychiatry  2014;14(1):269.
Suicide is a global issue among the elderly, but few studies have explored the experiences of suicide ideation in older Asian psychiatric outpatients.
Older psychiatric outpatients (N = 24) were recruited by convenience from one medical centre and one regional hospital in northern Taiwan. Participants were recruited if they met these inclusion criteria: 1) ≥65 years old, 2) without severe cognitive deficit, 3) outpatients in the psychiatric clinics at the selected hospitals, and 4) self-reported first episode of suicidal ideation within the previous year. Data were collected in individual interviews using a semi-structured guide and analysed by content analysis.
Suicide ideation was triggered by illness and physical discomfort, conflicts with family members/friends, illness of family members, death of family members/friends, and loneliness. Participants’ reasons for not executing suicide were family members’ and friends’ support, receiving treatment, finding a way to shift their attention, fear of increasing pressure on one’s children, religious beliefs, and not knowing how to execute suicide.
Understanding these identified triggers of suicide ideation may help psychiatrists open a channel for conversation with their elderly clients and more readily make their diagnosis. Understanding these identified protective factors against executing suicide can help psychiatrists not only treat depression, but also enhance protective factors for their clients.
PMCID: PMC4237773  PMID: 25403893
Suicide ideation; Psychiatric; Outpatients; Older people
20.  In Vitro Antibacterial Activity of a Novel Resin-Based Pulp Capping Material Containing the Quaternary Ammonium Salt MAE-DB and Portland Cement 
PLoS ONE  2014;9(11):e112549.
Vital pulp preservation in the treatment of deep caries is challenging due to bacterial infection. The objectives of this study were to synthesize a novel, light-cured composite material containing bioactive calcium-silicate (Portland cement, PC) and the antimicrobial quaternary ammonium salt monomer 2-methacryloxylethyl dodecyl methyl ammonium bromide (MAE-DB) and to evaluate its effects on Streptococcus mutans growth in vitro.
The experimental material was prepared from a 2∶1 ratio of PC mixed with a resin of 2-hydroxyethylmethacrylate, bisphenol glycerolate dimethacrylate, and triethylene glycol dimethacrylate (4∶3∶1) containing 5 wt% MAE-DB. Cured resin containing 5% MAE-DB without PC served as the positive control material, and resin without MAE-DB or PC served as the negative control material. Mineral trioxide aggregate (MTA) and calcium hydroxide (Dycal) served as commercial controls. S. mutans biofilm formation on material surfaces and growth in the culture medium were tested according to colony-forming units (CFUs) and metabolic activity after 24 h incubation over freshly prepared samples or samples aged in water for 6 months. Biofilm formation was also assessed by Live/Dead staining and scanning electron microscopy.
S. mutans biofilm formation on the experimental material was significantly inhibited, with CFU counts, metabolic activity, viability staining, and morphology similar to those of biofilms on the positive control material. None of the materials affected bacterial growth in solution. Contact-inhibition of biofilm formation was retained by the aged experimental material. Significant biofilm formation was observed on MTA and Dycal.
The synthesized material containing HEMA-BisGMA-TEGDMA resin with MAE-DB as the antimicrobial agent and PC to support mineralized tissue formation inhibited S. mutans biofilm formation even after aging in water for 6 months, but had no inhibitory effect on bacteria in solution. Therefore, this material shows promise as a pulp capping material for vital pulp preservation in the treatment of deep caries.
PMCID: PMC4229210  PMID: 25389975
21.  Rnd3 Regulates Lung Cancer Cell Proliferation through Notch Signaling 
PLoS ONE  2014;9(11):e111897.
Rnd3/RhoE is a small Rho GTPase involved in the regulation of different cell behaviors. Dysregulation of Rnd3 has been linked to tumorigenesis and metastasis. Lung cancers are the leading cause of cancer-related death in the West and around the world. The expression of Rnd3 and its ectopic role in non-small cell lung cancer (NSCLC) remain to be explored. Here, we reported that Rnd3 was down-regulated in three NSCLC cell lines: H358, H520 and A549. The down-regulation of Rnd3 led to hyper-activation of Rho Kinase and Notch signaling. The reintroduction of Rnd3 or selective inhibition of Notch signaling, but not Rho Kinase signaling, blocked the proliferation of H358 and H520 cells. Mechanistically, Notch intracellular domain (NICD) protein abundance in H358 cells was regulated by Rnd3-mediated NICD proteasome degradation. Rnd3 regulated H358 and H520 cell proliferation through a Notch1/NICD/Hes1 signaling axis independent of Rho Kinase.
PMCID: PMC4221162  PMID: 25372032
22.  Deficiency of IRTKS as an adaptor of insulin receptor leads to insulin resistance 
Cell Research  2013;23(11):1310-1321.
IRTKS encodes a member of the IRSp53/MIM homology domain family, which has been shown to play an important role in the formation of plasma membrane protrusions. Although the phosphorylation of IRTKS occurs in response to insulin stimulation, the role of this protein in insulin signaling remains unknown. Here we show that IRTKS-deficient mice exhibit insulin resistance, including hyperglycemia, hyperinsulinemia, glucose intolerance, decreased insulin sensitivity, and increased hepatic glucose production. The administration of ectopic IRTKS can ameliorate the insulin resistance of IRTKS-deficient and diabetic mice. In parallel, the expression level of IRTKS was significantly decreased in diabetic mouse model. Furthermore, DNA hypermethylation of the IRTKS promoter was also observed in these subjects. We also show that IRTKS, as an adaptor of the insulin receptor (IR), modulates IR-IRS1-PI3K-AKT signaling via regulating the phosphorylation of IR. These findings add new insights into our understanding of insulin signaling and resistance.
PMCID: PMC3817554  PMID: 23896986
insulin resistance; IRTKS; insulin receptor
23.  Comparative characterization of two intracellular Ca2+-release channels from the red flour beetle, Tribolium castaneum 
Scientific Reports  2014;4:6702.
Ryanodine receptors (RyRs) and inositol 1,4,5-trisphosphate receptors (IP3Rs) are members of a family of tetrameric intracellular Ca2+-release channels (CRCs). While it is well known in mammals that RyRs and IP3Rs modulate multiple physiological processes, the roles of these two CRCs in the development and physiology of insects remain poorly understood. In this study, we cloned and functionally characterized RyR and IP3R cDNAs (named TcRyR and TcIP3R) from the red flour beetle, Tribolium castaneum. The composite TcRyR gene contains an ORF of 15,285 bp encoding a protein of 5,094 amino acid residues. The TcIP3R contains an 8,175 bp ORF encoding a protein of 2,724 amino acids. Expression analysis of TcRyR and TcIP3R revealed significant differences in mRNA expression levels among T. castaneum during different developmental stages. When the transcript levels of TcRyR were suppressed by RNA interference (RNAi), an abnormal folding of the adult hind wings was observed, while the RNAi-mediated knockdown of TcIP3R resulted in defective larval–pupal and pupal–adult metamorphosis. These results suggested that TcRyR is required for muscle excitation-contraction (E-C) coupling in T. castaneum, and that calcium release via IP3R might play an important role in regulating ecdysone synthesis and release during molting and metamorphosis in insects.
PMCID: PMC4204029  PMID: 25330781
24.  Risk Factors for Bunyavirus-Associated Severe Fever with Thrombocytopenia Syndrome, China 
Severe fever with thrombocytopenia syndrome (SFTS) is an emerging disease that is caused by a novel bunyavirus, referred to as SFTS virus. During January 2011 to December 2011 we conducted a case-control study in Henan, Hubei and Shandong Provinces of China to determine the risk factors for SFTS.
Case-patients were identified in hospitals and reported to provincial Centers for Disease Control and Prevention while being notified electronically to the National Surveillance System. Controls were randomly selected from a pool of patients admitted to the same hospital ward within one week of the inclusion of the cases. They were matched by age (+/−5 years) and gender.
A total of 422 patients participated in the study including 134 cases and 288 matched controls. The median age of the cases was 58.8 years, ranging from 47.6 to 70.1 years; 54.5% were male. No differences in demographics were observed between cases and controls; however, farmers were frequent and more common among cases (88.8%) than controls (58.7%). In multivariate analysis, the odds for SFTS was 2.4∼4.5 fold higher with patients who reported tick bites or presence of tick in the living area. Other independent risk factors included cat or cattle ownership and reported presence of weeds and shrubs in the working environment.
Our findings support the hypothesis that ticks are important vectors of SFTS virus. Further investigations are warranted to understand the detailed modes of transmission of SFTS virus while vector management, education on tick bites prevention and personal hygiene management should be implemented for high-risk groups in high incidence areas.
Author Summary
Since 2009, an emerging infectious disease which was identified as the severe fever with thrombocytopenia syndrome (SFTS) was reported in rural areas of Hubei, Shandong and Henan provinces in China. A novel bunyavirus designated severe fever with thrombocytopenia syndrome bunyavirus (SFTSV) had been identified to be the etiological cause of SFTS. But what risk factors lead to the disease is still not clear. Further investigations for risk factors are needed to effectively prevent and control the disease. Here we have designed case-control study to try to develop the risk factors of the spread of SFTSV. It is hoped that our research could provide epidemiological evidence for further study. Also help to determine the spread of the virus in the environment.
PMCID: PMC4199554  PMID: 25330383
25.  Neuroprotective effect of lovastatin by inhibiting NMDA receptor1 in 6-hydroxydopamine treated PC12 cells 
In addition to original role of lowering cholesterol, statins display multiple neuroprotective mechanisms. In this study, 6-Hydroxydopamine (6-OHDA)-treated pheochromocytoma-12 (PC12) cells were used to investigate the neuroprotective nature of lovastatin. After incubation with 6-OHDA and/or lovastatin, test kits were used to detect the levels of LDH and glutamate, which were released from PC12 cells exposed to different culture media. The mRNA levels of TNF-α, and NMDAR1 were determined by RT-PCR and the protein levels were analyzed by western blot. Our results show that lovastatin significantly decreased both the mRNA and the protein levels of TNF-α and NMDAR1. ELISA assays revealed increased lactate dehydrogenase (LDH) and glutamate binding activity in 6-OHDA-lesioned PC12 cells, and this increase could be prevented by lovastatin. Our results suggest that lovastatin induces neuroprotection by inhibiting NMDAR1 and TNF-α. The data provide direct evidence of the potential application of lovastatin for the treatment of parkinson’s diseases.
PMCID: PMC4238522  PMID: 25419363
Parkinson’s disease; lovastatin; NMDA receptor1; TNF-α

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