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1.  Effects of Huangqi and bear bile on recurrent parotitis in children: a new clinical approach*  
Objective: To evaluate the pharmacological effects of traditional Chinese medicine, bear bile capsule and Huangqi granule, on recurrent parotitis in children. Methods: In this prospective, controlled, and randomized study, a total of 151 young children were divided into three groups: Group A included massaging the children’s parotid region and melting vitamin C in their mouth daily; Group B included swallowing bear bile capsule and Huangqi granule daily; and Group C included massages and vitamin C as prescribed in Group A, and traditional Chinese medicine as prescribed in Group B. Children were treated individually for one month and then a follow-up study was conducted for 1 to 3.5 years. Analysis of variance (ANOVA) and Ridit analysis were employed for statistical analysis. Results: The recurrence rate decreased in every group, but was significantly more in Groups B and C when compared to Group A. The recurrences significantly decreased (P<0.01) in Group B and their recovery rate was as high as 63%, significantly better than those of the other groups (P<0.01). Conclusions: Huangqi and bear bile could be a novel clinical approach for treating recurrent parotitis in children.
doi:10.1631/jzus.B1200072
PMCID: PMC3596577  PMID: 23463769
Juvenile recurrent parotitis; Therapy; Pediatrics; Traditional Chinese medicine; Prospective study
2.  VEGF-induced vascular permeability is mediated by FAK 
Developmental Cell  2012;22(1):146-157.
SUMMARY
Endothelial cells (ECs) form cell-cell adhesive junctional structures maintaining vascular integrity. This barrier is dynamically regulated by vascular endothelial growth factor (VEGF) receptor signaling. We created an inducible knockin mouse model to study the contribution of the integrin-associated focal adhesion tyrosine kinase (FAK) signaling on vascular function. Here we show that genetic or pharmacological FAK inhibition in ECs prevents VEGF-stimulated permeability downstream of VEGF receptor or Src tyrosine kinase activation in vivo. VEGF promotes tension-independent FAK activation, rapid FAK localization to cell-cell junctions, binding of the FAK FERM domain to the vascular endothelial cadherin (VE-cadherin) cytoplasmic tail, and direct FAK phosphorylation of β-catenin at tyrosine-142 (Y142) facilitating VE-cadherin-β-catenin dissociation and EC junctional breakdown. Kinase inhibited FAK is in a closed conformation that prevents VE-cadherin association and limits VEGF-stimulated β-catenin Y142 phosphorylation. Our studies establish a role for FAK as an essential signaling switch within ECs regulating adherens junction dynamics.
doi:10.1016/j.devcel.2011.11.002
PMCID: PMC3266538  PMID: 22264731
FAK; VEGF; knockin mouse; vascular permeability; β-catenin
3.  Specific and Functional Diversity of Endophytic Bacteria from Pine Wood Nematode Bursaphelenchus Xylophilus with Different Virulence 
Pine wilt disease (PWD) caused by the pine wood nematode (PWN), Bursaphelenchus xylophilus, is one of the most devastating diseases of Pinus spp. The PWN was therefore listed as one of the most dangerous forest pests in China meriting quarantine. Virulence of the PWN is closely linked with the spread of PWD. However, main factors responsible for the virulence of PWNs are still unclear. Recently epiphytic bacteria carried by PWNs have drawn much attention. But little is known about the relationship between endophytic bacteria and virulence of B. xylophilus. In this research, virulence of ten strains of B. xylophilus from different geographical areas in six provinces of China and four pine species were tested with 2-year-old seedlings of Pinus thunbergii. Endophytic bacteria were isolated from PWNs with different virulence to investigate the relationship between the bacteria and PWN virulence. Meanwhile, the carbon metabolism of endophytic bacteria from highly and low virulent B. xylophilus was analyzed using Biolog plates (ECO). The results indicated that ten strains of PWNs showed a wide range of virulence. Simultaneously, endophytic bacteria were isolated from 90% of the B. xylophilus strains. The dominant endophytic bacteria in the nematodes were identified as species of Stenotrophomonas, Achromobacter, Ewingella, Leifsonia, Rhizobium, and Pseudomonas using molecular and biochemical methods. Moreover, S. maltophilia, and A. xylosoxidans subsp. xylosoxidans were the predominant strains. Most of the strains (80%) from P. massoniana contained either S. maltophilia, A. xylosoxidans, or both species. There was a difference between the abilities of the endophytic bacteria to utilize carbon sources. Endophytic bacteria from highly virulent B. xylophilus had a relatively high utilization rate of carbohydrate and carboxylic acids, while bacteria from low virulent B. xylophilus made better use of amino acids. In conclusion, endophytic bacteria widely exist in B. xylophilus from different pines and areas; and B. xylophilus strains with different virulence possessed various endophytic bacteria and diverse carbon metabolism which suggested that the endophytic bacteria species and carbon metabolism might be related with the B. xylophilus virulence.
doi:10.7150/ijbs.5071
PMCID: PMC3535532  PMID: 23289015
pine wilt disease; Bursaphelenchus xylophilus; endophytic bacteria; virulence;  Pinus massoniana;  P. thunbergii.
4.  Transient filament occlusion of the middle cerebral artery in rats: does the reperfusion method matter 24 hours after perfusion? 
BMC Neuroscience  2012;13:154.
Background
There are two widely used transient middle cerebral artery occlusion (MCAO) methods, which differ in the use of unilateral or bilateral carotid artery reperfusion (UNICAR and BICAR). Of the two methods, UNICAR is easier to perform. This study was designed to comprehensively compare the two reperfusion methods to determine if there are any differences in outcomes.
Results
The UNICAR and BICAR groups each included 9 rats. At baseline, the average pO2 was 20.54 ± 9.35 and 26.43 ± 7.39, for the UNICAR and BICAR groups, respectively (P = 0.519). Changes in pO2, as well as other physiological parameters measured within the ischemic lesion, were similar between the UNICAR and BICAR groups during 90 min of MCAO and the first 30 min of reperfusion (all P > 0.05). Furthermore, both the Bederson score and Garcia score, which are used for neurological assessment, were also similar (both P > 0.05). There were also no significant differences in T2WI lesion volume, DWI lesion volume, PWI lesion volume, or TTC staining infarct volume between the two groups (all P > 0.05).
Conclusion
UNICAR and BICAR have similar capability for inducing acute brain ischemic injury and can be considered interchangeable up to 24 hours after reperfusion.
doi:10.1186/1471-2202-13-154
PMCID: PMC3546945  PMID: 23272656
Middle cerebral artery occlusion; Ischemia; Reperfusion method; Bilateral Carotid reperfusion; Unilateral Carotid reperfusion; Neurological deficits; Diffusion weighted imaging; Perfusion weighted imaging; Partial oxygen pressure
5.  Life-threatening hemorrhage after liver radiofrequency ablation successfully controlled by transarterial embolization 
World Journal of Hepatology  2012;4(12):419-421.
A 59-year-old man underwent liver radiofrequency ablation under laparotomy for recurrent hepatic carcinoma located in the caudate lobe, however, near-fatal bleeding occurred 1 wk after the operation. The intra-operative ultrasound study during laparotomy revealed left hepatic artery pseudoaneurysm. Suture and packing with ribbon gauze was used to obtain hemostasis. A secondary hemorrhage followed 11 h later and hepatic angiography was performed immediately. Bleeding from the pseudoaneurysm in a branch of the left hepatic artery was found and the artery branch was embolized with coils. Other than slight bile leakage, post-embolization continued satisfactorily. Bleeding did not reoccur. The follow up visit 1 mo later found the pseudoaneurysm disappearing and no tumor recurrence.
doi:10.4254/wjh.v4.i12.419
PMCID: PMC3554810  PMID: 23355924
Hepatocellular carcinoma; Radiofrequency ablation; Complication; Hepatic angiography; Embolization
6.  Nuclear-localized focal adhesion kinase regulates inflammatory VCAM-1 expression 
The Journal of Cell Biology  2012;197(7):907-919.
Kinase-inhibited FAK limits VCAM-1 production via nuclear localization and promotion of GATA4 turnover.
Vascular cell adhesion molecule–1 (VCAM-1) plays important roles in development and inflammation. Tumor necrosis factor–α (TNF-α) and focal adhesion kinase (FAK) are key regulators of inflammatory and integrin–matrix signaling, respectively. Integrin costimulatory signals modulate inflammatory gene expression, but the important control points between these pathways remain unresolved. We report that pharmacological FAK inhibition prevented TNF-α–induced VCAM-1 expression within heart vessel–associated endothelial cells in vivo, and genetic or pharmacological FAK inhibition blocked VCAM-1 expression during development. FAK signaling facilitated TNF-α–induced, mitogen-activated protein kinase activation, and, surprisingly, FAK inhibition resulted in the loss of the GATA4 transcription factor required for TNF-α–induced VCAM-1 production. FAK inhibition also triggered FAK nuclear localization. In the nucleus, the FAK-FERM (band 4.1, ezrin, radixin, moesin homology) domain bound directly to GATA4 and enhanced its CHIP (C terminus of Hsp70-interacting protein) E3 ligase–dependent polyubiquitination and degradation. These studies reveal new developmental and anti-inflammatory roles for kinase-inhibited FAK in limiting VCAM-1 production via nuclear localization and promotion of GATA4 turnover.
doi:10.1083/jcb.201109067
PMCID: PMC3384409  PMID: 22734001
7.  Lipopolysaccharide-Induced Expression of Microsomal Prostaglandin E Synthase-1 Mediates Late-Phase PGE2 Production in Bone Marrow Derived Macrophages 
PLoS ONE  2012;7(11):e50244.
Cyclooxygenase (COX)-2 expression and release of prostaglandins (PGs) by macrophages are consistent features of lipopolysaccharide (LPS)-induced macrophage inflammation. The two major PGs, PGE2 and PGD2, are synthesized by the prostanoid isomerases, PGE synthases (PGES) and PGD synthases (PGDS), respectively. Since the expression profile and the individual role of these prostanoid isomerases-mediated inflammation in macrophages has not been defined, we examined the LPS-stimulated PGs production pattern and the expression profile of their synthases in the primary cultured mouse bone marrow derived macrophages (BMDM). Our data show that LPS induced both PGE2 and PGD2 production, which was evident by ∼8 hrs and remained at a similar ratio (∼1∶1) in the early phase (≤12 hrs) of LPS treatment. However, PGE2 production continued increase further in the late phase (16–24 hrs); whereas the production of PGD2 remained at a stable level from 12 to 24 hrs post-treatment. In response to LPS-treatment, the expression of both COX-2 and inducible nitric oxide synthase (iNOS) was detected within 2 to 4 hrs; whereas the increased expression of microsomal PGES (mPGES)-1 and a myeloid cell transcription factor PU.1 did not appear until later phase (≥12 hrs). In contrast, the expression of COX-1, hematopoietic-PGDS (H-PGDS), cytosolic-PGES (c-PGES), or mPGES-2 in BMDM was not affected by LPS treatment. Selective inhibition of mPGES-1 with either siRNA or isoform-selective inhibitor CAY10526, but not mPGES-2, c-PGES or PU.1, attenuated LPS-induced burst of PGE2 production indicating that mPGES-1 mediates LPS-induced PGE2 production in BMDM. Interestingly, selective inhibition of mPGES-1 was also associated with a decrease in LPS-induced iNOS expression. In summary, our data show that mPGES-1, but not mPGES-2 or c-PGES isomerase, mediates LPS-induced late-phase burst of PGE2 generation, and regulates LPS-induced iNOS expression in BMDM.
doi:10.1371/journal.pone.0050244
PMCID: PMC3511480  PMID: 23226252
8.  TRB3 Gene Silencing Alleviates Diabetic Cardiomyopathy in a Type 2 Diabetic Rat Model 
Diabetes  2011;60(11):2963-2974.
OBJECTIVE
Tribbles 3 (TRB3) is associated with insulin resistance, an important trigger in the development of diabetic cardiomyopathy (DCM). We sought to determine whether TRB3 plays a major role in modulating DCM and the mechanisms involved.
RESEARCH DESIGN AND METHODS
The type 2 diabetic rat model was induced by high-fat diet and low-dose streptozotocin. We evaluated the characteristics of type 2 DCM by serial echocardiography and metabolite tests, Western blot analysis for TRB3 expression, and histopathologic analyses of cardiomyocyte density, lipids accumulation, cardiac inflammation, and fibrosis area. We then used gene silencing to investigate the role of TRB3 in the pathophysiologic features of DCM.
RESULTS
Rats with DCM showed severe insulin resistance, left ventricular dysfunction, aberrant lipids deposition, cardiac inflammation, fibrosis, and TRB3 overexpression. We found that the silencing of TRB3 ameliorated metabolic disturbance and insulin resistance; myocardial hypertrophy, lipids accumulation, inflammation, fibrosis, and elevated collagen I-to-III content ratio in DCM rats were significantly decreased. These anatomic findings were accompanied by significant improvements in cardiac function. Furthermore, with TRB3 gene silencing, the inhibited phosphorylation of Akt was restored and the increased phosphorylation of extracellular signal–regulated kinase 1/2 and Jun NH2-terminal kinase in DCM was significantly decreased.
Conclusions.
TRB3 gene silencing may exert a protective effect on DCM by improving selective insulin resistance, implicating its potential role for treatment of human DCM.
doi:10.2337/db11-0549
PMCID: PMC3198078  PMID: 21933987
9.  Inhibition of Tcf-4 Induces Apoptosis and Enhances Chemosensitivity of Colon Cancer Cells 
PLoS ONE  2012;7(9):e45617.
Aberrant activation of β-catenin/Tcf-4 signaling has been implicated in human carcinogenesis, including colorectal cancer. In this study, we compared the effects of Tcf-4 knockdown with β-catenin knockdown on cell proliferation, apoptosis, and chemosensitivity in SW480 and HCT116 colon cancer cells using adenoviral vector-mediated short hairpin RNA (shRNA). Our results show that, compared to β-catenin knockdown, Tcf-4 knockdown more effectively inhibited colony formation, induced apoptosis, and increased 5-FU and oxaliplatin-mediated cytotoxicity in colon cancer cells. We further investigated the mechanisms involved in the different efficacies observed with β-catenin and Tcf-4 knockdown in colon cancer cells. FOXO4 is a member of the subfamily of mammalian FOXO forkhead transcription factors and plays a major role in controlling cellular proliferation, apoptosis, and DNA repair. Our data showed that the protein level of FOXO4 did not change after treatment with both β-catenin and Tcf-4 shRNA. However, β-catenin shRNA was found to increase the accumulation of phosphorylated FOXO4 S193 and decrease the expression of FOXO target genes p27Kip1 and MnSOD, whereas Tcf-4 shRNA showed the opposite effect. Therefore, compared to β-catenin knockdown, Tcf-4 knockdown shows better efficacy for inhibiting proliferation and inducing apoptosis of colorectal cancer cells, which may be related to increased FOXO4 transcriptional activity. These results suggest that Tcf-4 is an attractive potential therapeutic target for colorectal cancer therapy.
doi:10.1371/journal.pone.0045617
PMCID: PMC3454396  PMID: 23029137
10.  Bacteria in Crude Oil Survived Autoclaving and Stimulated Differentially by Exogenous Bacteria 
PLoS ONE  2012;7(9):e40842.
Autoclaving of crude oil is often used to evaluate the hydrocarbon-degrading abilities of bacteria. This may be potentially useful for bioaugmentation and microbial enhanced oil recovery (MEOR). However, it is not entirely clear if “endogenous” bacteria (e.g., spores) in/on crude oil survive the autoclaving process, or influence subsequent evaluation of the hydrocarbon-degradation abilities of the “exogenous” bacterial strains. To test this, we inoculated autoclaved crude oil medium with six exogenous bacterial strains (three Dietzia strains, two Acinetobacter strains, and one Pseudomonas strain). The survival of the spore-forming Bacillus and Paenibacillus and the non-spore-forming mesophilic Pseudomonas, Dietzia, Alcaligenes, and Microbacterium was detected using a 16S rRNA gene clone library and terminal restriction fragment length polymorphism (T-RFLP) analysis. However, neither bacteria nor bacterial activity was detected in three controls consisting of non-inoculated autoclaved crude oil medium. These results suggest that detection of endogenous bacteria was stimulated by the six inoculated strains. In addition, inoculation with Acinetobacter spp. stimulated detection of Bacillus, while inoculation with Dietzia spp. and Pseudomonas sp. stimulated the detection of more Pseudomonas. In contrast, similar exogenous bacteria stimulated similar endogenous bacteria at the genus level. Based on these results, special emphasis should be applied to evaluate the influence of bacteria capable of surviving autoclaving on the hydrocarbon-degrading abilities of exogenous bacteria, in particular, with regard to bioaugmentation and MEOR. Bioaugmentation and MEOR technologies could then be developed to more accurately direct the growth of specific endogenous bacteria that may then improve the efficiency of treatment or recovery of crude oil.
doi:10.1371/journal.pone.0040842
PMCID: PMC3444520  PMID: 23028421
11.  In vitro differentiation of rat embryonic stem cells into functional cardiomyocytes 
Cell Research  2011;21(9):1316-1331.
The recent breakthrough in the generation of rat embryonic stem cells (rESCs) opens the door to application of gene targeting to create models for the study of human diseases. In addition, the in vitro differentiation system from rESCs into derivatives of three germ layers will serve as a powerful tool and resource for the investigation of mammalian development, cell function, tissue repair, and drug discovery. However, these uses have been limited by the difficulty of in vitro differentiation. The aims of this study were to establish an in vitro differentiation system from rESCs and to investigate whether rESCs are capable of forming terminal-differentiated cardiomyocytes. Using newly established rESCs, we found that embryoid body (EB)-based method used in mouse ESC (mESC) differentiation failed to work for the serum-free cultivated rESCs. We then developed a protocol by combination of three chemical inhibitors and feeder-conditioned medium. Under this condition, rESCs formed EBs, propagated and differentiated into three embryonic germ layers. Moreover, rESC-formed EBs could differentiate into spontaneously beating cardiomyocytes after plating. Analyses of molecular, structural, and functional properties revealed that rESC-derived cardiomyocytes were similar to those derived from fetal rat hearts and mESCs. In conclusion, we successfully developed an in vitro differentiation system for rESCs through which functional myocytes were generated and displayed phenotypes of rat fetal cardiomyocytes. This unique cellular system will provide a new approach to study the early development and cardiac function, and serve as an important tool in pharmacological testing and cell therapy.
doi:10.1038/cr.2011.48
PMCID: PMC3193466  PMID: 21423272
rat ES cells; differentiation; cardiomyocytes
13.  Evaluation of a novel hybrid bioartificial liver based on a multi-layer flat-plate bioreactor 
AIM: To evaluate the efficacy and safety of a hybrid bioartificial liver (HBAL) system in the treatment of acute liver failure.
METHODS: Canine models with acute liver failure were introduced with intravenous administration of D-galactosamine. The animals were divided into: the HBAL treatment group (n = 8), in which the canines received a 3-h treatment of HBAL; the bioartificial liver (BAL) treatment group (n = 8), in which the canines received a 3-h treatment of BAL; the non-bioartificial liver (NBAL) treatment group (n = 8), in which the canines received a 3-h treatment of NBAL; the control group (n = 8), in which the canines received no additional treatment. Biochemical parameters and survival time were determined. Levels of xenoantibodies, RNA of porcine endogenous retrovirus (PERV) and reverse transcriptase (RT) activity in the plasma were detected.
RESULTS: Biochemical parameters were significantly decreased in all treatment groups. The TBIL level in the HBAL group was lower than that in other groups (2.19 ± 0.55 μmol/L vs 24.2 ± 6.45 μmol/L, 12.47 ± 3.62 μmol/L, 3.77 ± 1.83 μmol/L, P < 0.05). The prothrombin time (PT) in the BAL and HBAL groups was significantly shorter than the NBAL and control groups (18.47 ± 4.41 s, 15.5 ± 1.56 s vs 28.67 ± 5.71 s, 21.71 ± 3.4 s, P < 0.05), and the PT in the HBAL group was shortest of all the groups. The albumin in the BAL and HBAL groups significantly increased and a significantly higher level was observed in the HBAL group compared with the BAL group (27.7 ± 1.7 g/L vs 25.24 ± 1.93 g/L). In the HBAL group, the ammonia levels significantly decreased from 54.37 ± 6.86 to 37.75 ± 6.09 after treatment (P < 0.05); there were significant difference in ammonia levels between other the groups (P < 0.05). The levels of antibodies were similar before and after treatment. The PERV RNA and the RT activity in the canine plasma were all negative.
CONCLUSION: The HBAL showed great efficiency and safety in the treatment of acute liver failure.
doi:10.3748/wjg.v18.i28.3752
PMCID: PMC3406430  PMID: 22851870
Hybrid bioartificial liver; Acute liver failure; Flat plate bioreactor; Co-culture; Nanofiber scaffold
14.  FAK promotes recruitment of talin to nascent adhesions to control cell motility 
The Journal of Cell Biology  2012;196(2):223-232.
An alternative linkage is shown whereby FAK brings talin to nascent adhesions independent of talin binding to β1 integrins.
Cell migration is a dynamic process that involves the continuous formation, maturation, and turnover of matrix–cell adhesion sites. New (nascent) adhesions form at the protruding cell edge in a tension-independent manner and are comprised of integrin receptors, signaling, and cytoskeletal-associated proteins. Integrins recruit focal adhesion kinase (FAK) and the cytoskeletal protein talin to nascent adhesions. Canonical models support a role for talin in mediating FAK localization and activation at adhesions. Here, alternatively, we show that FAK promotes talin recruitment to nascent adhesions occurring independently of talin binding to β1 integrins. The direct binding site for talin on FAK was identified, and a point mutation in FAK (E1015A) prevented talin association and talin localization to nascent adhesions but did not alter integrin-mediated FAK recruitment and activation at adhesions. Moreover, FAK E1015A inhibited cell motility and proteolytic talin cleavage needed for efficient adhesion dynamics. These results support an alternative linkage for FAK–talin interactions within nascent adhesions essential for the control of cell migration.
doi:10.1083/jcb.201108078
PMCID: PMC3265949  PMID: 22270917
15.  Microbiological safety of a novel bio-artificial liver support system based on porcine hepatocytes: a experimental study 
Background
Our institute has developed a novel bio-artificial liver (BAL) support system, based on a multi-layer radial-flow bioreactor carrying porcine hepatocytes and mesenchymal stem cells. It has been shown that porcine hepatocytes are capable of carrying infectious porcine endogenous retroviruses (PERVs) into human cells, thus the microbiological safety of any such system must be confirmed before clinical trials can be performed. In this study, we focused on assessing the status of PERV infection in beagles treated with the novel BAL.
Methods
Five normal beagles were treated with the novel BAL for 6 hours. The study was conducted for 6 months, during which plasma was collected from the BAL and whole blood from the beagles at regular intervals. DNA and RNA in both the collected peripheral blood mononuclear cells (PBMCs) and plasma samples were extracted for conventional PCR and reverse transcriptase (RT)-PCR with PERV-specific primers and the porcine-specific primer Sus scrofa cytochrome B. Meanwhile, the RT activity and the in vitro infectivity of the plasma were measured.
Results
Positive PERV RNA and RT activity were detected only in the plasma samples taken from the third circuit of the BAL system. All other samples including PBMCs and other plasma samples were negative for PERV RNA, PERV DNA, and RT activity. In the in vitro infection experiment, no infection was found in HEK293 cells treated with plasma.
Conclusions
No infective PERV was detected in the experimental animals, thus the novel BAL had a reliable microbiological safety profile.
doi:10.1186/2047-783X-17-13
PMCID: PMC3419623  PMID: 22632261
Microbiological safety; Porcine endogenous retrovirus; Bio-artificial liver; Porcine hepatocyte; Mesenchymal stem cells
16.  Rgnef (p190RhoGEF) Knockout Inhibits RhoA Activity, Focal Adhesion Establishment, and Cell Motility Downstream of Integrins 
PLoS ONE  2012;7(5):e37830.
Background
Cell migration is a highly regulated process that involves the formation and turnover of cell-matrix contact sites termed focal adhesions. Rho-family GTPases are molecular switches that regulate actin and focal adhesion dynamics in cells. Guanine nucleotide exchange factors (GEFs) activate Rho-family GTPases. Rgnef (p190RhoGEF) is a ubiquitous 190 kDa GEF implicated in the control of colon carcinoma and fibroblast cell motility.
Principal Findings
Rgnef exon 24 floxed mice (Rgnefflox) were created and crossed with cytomegalovirus (CMV)-driven Cre recombinase transgenic mice to inactivate Rgnef expression in all tissues during early development. Heterozygous RgnefWT/flox (Cre+) crosses yielded normal Mendelian ratios at embryonic day 13.5, but Rgnefflox/flox (Cre+) mice numbers at 3 weeks of age were significantly less than expected. Rgnefflox/flox (Cre+) (Rgnef−/−) embryos and primary mouse embryo fibroblasts (MEFs) were isolated and verified to lack Rgnef protein expression. When compared to wildtype (WT) littermate MEFs, loss of Rgnef significantly inhibited haptotaxis migration, wound closure motility, focal adhesion number, and RhoA GTPase activation after fibronectin-integrin stimulation. In WT MEFs, Rgnef activation occurs within 60 minutes upon fibronectin plating of cells associated with RhoA activation. Rgnef−/− MEF phenotypes were rescued by epitope-tagged Rgnef re-expression.
Conclusions
Rgnef−/− MEF phenotypes were due to Rgnef loss and support an essential role for Rgnef in RhoA regulation downstream of integrins in control of cell migration.
doi:10.1371/journal.pone.0037830
PMCID: PMC3359313  PMID: 22649559
17.  Regulation of Neuronal Cell Death by c-Abl-Hippo/MST2 Signaling Pathway 
PLoS ONE  2012;7(5):e36562.
Background
Mammalian Ste20-like kinases (MSTs) are the mammalian homologue of Drosophila hippo and play critical roles in regulation of cell death, organ size control, proliferation and tumorigenesis. MSTs exert pro-apoptotic function through cleavage, autophosphorylation and in turn phosphorylation of downstream targets, such as Histone H2B and FOXO (Forkhead box O). Previously we reported that protein kinase c-Abl mediates oxidative stress-induced neuronal cell death through phosphorylating MST1 at Y433, which is not conserved among mammalian MST2, Drosophila Hippo and C.elegans cst-1/2.
Methodology/Principal Findings
Using immunoblotting, in vitro kinase and cell death assay, we demonstrate that c-Abl kinase phosphorylates MST2 at an evolutionarily conserved site, Y81, within the kinase domain. We further show that the phosphorylation of MST2 by c-Abl leads to the disruption of the interaction with Raf-1 proteins and the enhancement of homodimerization of MST2 proteins. It thereby enhances the MST2 activation and induces neuronal cell death.
Conclusions/Significance
The identification of the c-Abl tyrosine kinase as a novel upstream activator of MST2 suggests that the conserved c-Abl-MST signaling cascade plays an important role in oxidative stress-induced neuronal cell death.
doi:10.1371/journal.pone.0036562
PMCID: PMC3348883  PMID: 22590567
19.  Regulation of Spike Timing-Dependent Plasticity of Olfactory Inputs in Mitral Cells in the Rat Olfactory Bulb 
PLoS ONE  2012;7(4):e35001.
The recent history of activity input onto granule cells (GCs) in the main olfactory bulb can affect the strength of lateral inhibition, which functions to generate contrast enhancement. However, at the plasticity level, it is unknown whether and how the prior modification of lateral inhibition modulates the subsequent induction of long-lasting changes of the excitatory olfactory nerve (ON) inputs to mitral cells (MCs). Here we found that the repetitive stimulation of two distinct excitatory inputs to the GCs induced a persistent modification of lateral inhibition in MCs in opposing directions. This bidirectional modification of inhibitory inputs differentially regulated the subsequent synaptic plasticity of the excitatory ON inputs to the MCs, which was induced by the repetitive pairing of excitatory postsynaptic potentials (EPSPs) with postsynaptic bursts. The regulation of spike timing-dependent plasticity (STDP) was achieved by the regulation of the inter-spike-interval (ISI) of the postsynaptic bursts. This novel form of inhibition-dependent regulation of plasticity may contribute to the encoding or processing of olfactory information in the olfactory bulb.
doi:10.1371/journal.pone.0035001
PMCID: PMC3334975  PMID: 22536347
20.  Clinical features of ankylosing spondylitis associated with acute anterior uveitis in Chinese patients 
AIM
To characterize the clinical features, diagnosis, treatment and prognosis of uveitis associated with ankylosing spondylitis (AS) in Chinese patients.
METHODS
Two hundred and three patients with uveitis associated with AS followed-up in the Third Military Medical University Daping Hospital between 2005 and 2010 were retrospectively evaluated in this study. Complete ophthalmological examinations were evaluated at baseline and during the follow-up period. The gender, age, follow-up time, mean frequency of uveitis onset, and accompanying eye examination findings, history, demographical parameters were reviewed. All the patients presented complete clinical and radiologic (sacroiliac, lumbar, dorsal and cervical spine, knee, ankle, shoulder, hip, elbow) evaluation. HLA-B27 typing was also searched.
RESULTS
There were 203 patients diagnosed with AS associated uveitis. All showed sacroiliac X-ray changes indicative of AS. There were 184 male and 19 female patients. The average age of patients was 35±12 (range 18–50). Mean follow-up period was 2.4 years (1-5 years). Acute anterior uveitis was the most common type of uveitis in both genders. 121 eyes presented unilateral involvement (55.2%), and 92 eyes presented bilateral involvement (45.3%) with onset alternately. 22 eyes occurred hypopyon, 16 eyes were found anterior vitreous cells, 7 eyes were noted reactive macular edema or exudation, 29 eyes presented posterior synechiae of iris, and 14 eyes presented cataract, 9 eyes presented secondary glaucoma, 2 eyes presented bend corneal degeneration and 1 eyes presented atrophy of eyeball. At the final visit, uveitis was well controlled in most patients.
CONCLUSION
AS associated with uveitis in Chinese patients mainly manifests as acute anterior uveitis. A combination of corticosteroids with other mydriasis agents is effective for most AS associated with uveitis patients. In general, the prognosis is good in these cases.
doi:10.3980/j.issn.2222-3959.2012.02.09
PMCID: PMC3359030  PMID: 22762042
HLA-B27; anterior uveitis; acute anterior uveitis; ankylosing spondylitis associated uveitis; HLA-B27 associated uveitis
21.  The N-methyl-D-aspartate receptor modulator GLYX-13 enhances learning and memory, in young adult and learning impaired aging rats 
Neurobiology of aging  2009;32(4):698-706.
NMDA Receptor (NMDAR) activity has been strongly implicated in both in-vitro and in-vivo learning models and the decline in cognitive function associated with aging and is linked to a decrease in NMDAR functional expression. GLYX-13 is a tetrapeptide (Thr-Pro-Pro-Thr) which acts as a NMDAR receptor partial agonist at the glycine site. GLYX-13 was administered to young adult (3 month old) and aged (27–32 month old) Fischer 344 X Brown Norway F1 rats (FBNF1), and behavioral learning tested in trace eyeblink conditioning (tEBC), a movable platform version of the Morris water maze (MWM), and alternating t-maze tasks. GLYX-13 (1 mg/kg i.v.) enhanced learning in both young adult and aging animals for MWM and alternating t-maze, and increased tEBC in aging rats. We previously showed optimal enhancement of tEBC in young adult rats given GLYX-13 at the same dose. Of these learning tasks, the MWM showed the most robust age related deficit in learning. In the MWM, GLYX-13 enhancement of learning was greater in the old compared to the young adult animals. Examination of the induction of long-term potentiation (LTP) and depression (LTD) at Schaffer collateral-CA1 synapses in hippocampal slices showed that aged rats showed marked, selective impairment in the magnitude of LTP evoked by a sub-maximal tetanus, and that GLYX-13 significantly enhanced the magnitude of LTP in slices from both young adult and aged rats without affecting LTD. These data, combined with the observation that the GLYX-13 enhancement of learning was greater in old than in young adult animals, suggest that GLYX-13 may be a promising treatment for deficits in cognitive function associated with aging.
doi:10.1016/j.neurobiolaging.2009.04.012
PMCID: PMC3035742  PMID: 19446371
learning; memory; aging; rat; hippocampus; eyeblink conditioning, water maze, t-maze, GLYX-13
22.  Two Novel Alkane Hydroxylase-Rubredoxin Fusion Genes Isolated from a Dietzia Bacterium and the Functions of Fused Rubredoxin Domains in Long-Chain n-Alkane Degradation▿  
Applied and Environmental Microbiology  2011;77(20):7279-7288.
Two alkane hydroxylase-rubredoxin fusion gene homologs (alkW1 and alkW2) were cloned from a Dietzia strain, designated DQ12-45-1b, which can grow on crude oil and n-alkanes ranging in length from 6 to 40 carbon atoms as sole carbon sources. Both AlkW1 and AlkW2 have an integral-membrane alkane monooxygenase (AlkB) conserved domain and a rubredoxin (Rd) conserved domain which are fused together. Phylogenetic analysis showed that these two AlkB-fused Rd domains formed a novel third cluster with all the Rds from the alkane hydroxylase-rubredoxin fusion gene clusters in Gram-positive bacteria and that this third cluster was distant from the known AlkG1- and AlkG2-type Rds. Expression of the alkW1 gene in DQ12-45-1b was induced when cells were grown on C8 to C32 n-alkanes as sole carbon sources, but expression of the alkW2 gene was not detected. Functional heterologous expression in an alkB deletion mutant of Pseudomonas fluorescens KOB2Δ1 suggested the alkW1 could restore the growth of KOB2Δ1 on C14 and C16 n-alkanes and induce faster growth on C18 to C32 n-alkanes than alkW1ΔRd, the Rd domain deletion mutant gene of alkW1, which also caused faster growth than KOB2Δ1 itself. In addition, the artificial fusion of AlkB from the Gram-negative P. fluorescens CHA0 and the Rds from both Gram-negative P. fluorescens CHA0 and Gram-positive Dietzia sp. DQ12-45-1b significantly increased the degradation of C32 alkane compared to that seen with AlkB itself. In conclusion, the alkW1 gene cloned from Dietzia species encoded an alkane hydroxylase which increased growth on and degradation of n-alkanes up to C32 in length, with its fused rubredoxin domain being necessary to maintain the functions. In addition, the fusion of alkane hydroxylase and rubredoxin genes from both Gram-positive and -negative bacteria can increase the degradation of long-chain n-alkanes (such as C32) in the Gram-negative bacterium.
doi:10.1128/AEM.00203-11
PMCID: PMC3194844  PMID: 21873474
23.  Reprogramming of ovine adult fibroblasts to pluripotency via drug-inducible expression of defined factors 
Cell Research  2011;21(4):600-608.
Reprogramming of somatic cells in the enucleated egg made Dolly, the sheep, the first successfully cloned mammal in 1996. However, the mechanism of sheep somatic cell reprogramming has not yet been addressed. Moreover, sheep embryonic stem (ES) cells are still not available, which limits the generation of precise gene-modified sheep. In this study, we report that sheep somatic cells can be directly reprogrammed to induced pluripotent stem (iPS) cells using defined factors (Oct4, Sox2, c-Myc, Klf4, Nanog, Lin28, SV40 large T and hTERT). Our observations indicated that somatic cells from sheep are more difficult to reprogram than somatic cells from other species, in which iPS cells have been reported. We demonstrated that sheep iPS cells express ES cell markers, including alkaline phosphatase, Oct4, Nanog, Sox2, Rex1, stage-specific embryonic antigen-1, TRA-1-60, TRA-1-81 and E-cadherin. Sheep iPS cells exhibited normal karyotypes and were able to differentiate into all three germ layers both in vitro and in teratomas. Our study may help to reveal the mechanism of somatic cell reprogramming in sheep and provide a platform to explore the culture conditions for sheep ES cells. Moreover, sheep iPS cells may be directly used to generate precise gene-modified sheep.
doi:10.1038/cr.2011.6
PMCID: PMC3203662  PMID: 21221129
sheep; pluripotency; reprogram; iPS cells; embryonic stem cells
24.  Microbial Communities in Long-Term, Water-Flooded Petroleum Reservoirs with Different in situ Temperatures in the Huabei Oilfield, China 
PLoS ONE  2012;7(3):e33535.
The distribution of microbial communities in the Menggulin (MGL) and Ba19 blocks in the Huabei Oilfield, China, were studied based on 16S rRNA gene analysis. The dominant microbes showed obvious block-specific characteristics, and the two blocks had substantially different bacterial and archaeal communities. In the moderate-temperature MGL block, the bacteria were mainly Epsilonproteobacteria and Alphaproteobacteria, and the archaea were methanogens belonging to Methanolinea, Methanothermobacter, Methanosaeta, and Methanocella. However, in the high-temperature Ba19 block, the predominant bacteria were Gammaproteobacteria, and the predominant archaea were Methanothermobacter and Methanosaeta. In spite of shared taxa in the blocks, differences among wells in the same block were obvious, especially for bacterial communities in the MGL block. Compared to the bacterial communities, the archaeal communities were much more conserved within blocks and were not affected by the variation in the bacterial communities.
doi:10.1371/journal.pone.0033535
PMCID: PMC3303836  PMID: 22432032
25.  Complete Genome Sequence of Amycolicicoccus subflavusDQS3-9A1T, an Actinomycete Isolated from Crude Oil-Polluted Soil ▿  
Journal of Bacteriology  2011;193(17):4538-4539.
Amycolicicoccus subflavusDQS3-9A1T, isolated from crude oil-polluted soil in the Daqing Oilfield in China, is a type strain of a newly published novel species in the novel genus Amycolicicoccus. Here we report the complete genome of DQS3-9A1Tand genes associated with oil-polluted environment.
doi:10.1128/JB.05388-11
PMCID: PMC3165522  PMID: 21725023

Results 1-25 (62)