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1.  Protective Efficacy of Centralized and Polyvalent Envelope Immunogens in an Attenuated Equine Lentivirus Vaccine 
PLoS Pathogens  2015;11(1):e1004610.
Lentiviral Envelope (Env) antigenic variation and related immune evasion present major hurdles to effective vaccine development. Centralized Env immunogens that minimize the genetic distance between vaccine proteins and circulating viral isolates are an area of increasing study in HIV vaccinology. To date, the efficacy of centralized immunogens has not been evaluated in the context of an animal model that could provide both immunogenicity and protective efficacy data. We previously reported on a live-attenuated (attenuated) equine infectious anemia (EIAV) virus vaccine, which provides 100% protection from disease after virulent, homologous, virus challenge. Further, protective efficacy demonstrated a significant, inverse, linear relationship between EIAV Env divergence and protection from disease when vaccinates were challenged with viral strains of increasing Env divergence from the vaccine strain Env. Here, we sought to comprehensively examine the protective efficacy of centralized immunogens in our attenuated vaccine platform. We developed, constructed, and extensively tested a consensus Env, which in a virulent proviral backbone generated a fully replication-competent pathogenic virus, and compared this consensus Env to an ancestral Env in our attenuated proviral backbone. A polyvalent attenuated vaccine was established for comparison to the centralized vaccines. Additionally, an engineered quasispecies challenge model was created for rigorous assessment of protective efficacy. Twenty-four EIAV-naïve animals were vaccinated and challenged along with six-control animals six months post-second inoculation. Pre-challenge data indicated the consensus Env was more broadly immunogenic than the Env of the other attenuated vaccines. However, challenge data demonstrated a significant increase in protective efficacy of the polyvalent vaccine. These findings reveal, for the first time, a consensus Env immunogen that generated a fully-functional, replication-competent lentivirus, which when experimentally evaluated, demonstrated broader immunogenicity that does not equate to higher protective efficacy.
Author Summary
Our best effort for containment of the global HIV epidemic is the development of a broadly protective vaccine. Current research has focused on vaccines that can generate a protective immune response against numerous strains of the virus. For this reason, vaccines with centralized HIV genes as immunogens, which merge HIV genetic information and potentially protect against multiple viral strains in a single inoculation, are an increasing area of interest to the field. Existing published studies have not evaluated centralized immunogens in the context of attenuated vaccines, which to date, have demonstrated the highest level of vaccine protection in lentiviral studies. Furthermore, centralized immunogen studies have also not included protective efficacy findings accomplished through challenge with highly pathogenic virus strains. In this study we not only examine the immunogenicity of these immunogens in an animal model, but we also for the first time evaluate the ability of centralized immunogens to induce protection against virulent virus challenge.
doi:10.1371/journal.ppat.1004610
PMCID: PMC4287611  PMID: 25569288
2.  Sphingosine 1-phosphate (S1P) promotes mitochondrial biogenesis in Hep G2 cells by activating Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) 
Cell Stress & Chaperones  2013;19(4):541-548.
Sphingosine 1-phosphate (S1P), a potent bioactive phospholipid, has been reported to regulate a broad spectrum of biological processes. However, little is known regarding S1P’s effects on mitochondrial function. In this study, we investigated the S1P’s effects on the Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) signaling pathway and mitochondrial biogenesis in Hep G2 cells. Our results indicate that administration of S1P leads to a significant upregulation of mitochondrial DNA replication and transcription, increased mitochondrial mass, and elevated adenosine triphosphate synthesis. In addition, we found that treatment with S1P stimulates expression of PGC-1α, a master regulator of mitochondrial biogenesis, as well as its downstream targets: nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (TFAM). Moreover, our data demonstrate that S1P’s effects on PGC-1α and mitochondrial biogenesis are mediated by the protein kinase A/cAMP response element-binding protein (PKA/CREB) pathway. Importantly, we also revealed that S1P’s effects on mitochondrial biogenesis are dependent on its type 2 receptor (S1P2), though not on either its type 1 (S1P1) or type 3 (S1P3) receptors. Based on these observations, we concluded that S1P activates the PKA/CREB pathway through S1P2, which then promotes expression of PGC-1α/NRF1/TFAM and subsequent mitochondrial biogenesis in Hep G2 cells.
doi:10.1007/s12192-013-0480-5
PMCID: PMC4041936  PMID: 24293320
Sphingosine 1-phosphate (S1P); Peroxisome proliferator-activated receptor c coactivator 1α (PGC-1α); Mitochondrial biogenesis; Mitochondrial DNA; cAMP response element-binding protein (CREB)
3.  Protective effects of acacetin isolated from Ziziphora clinopodioides Lam. (Xintahua) on neonatal rat cardiomyocytes 
Chinese Medicine  2014;9(1):28.
Background
The total flavonoids from ethanol extract of the aerial part of Ziziphora clinopodioides Lam. (Lamlaceae) (Xintahua) showed protective activities against rat acute myocardial ischemia in rats. This study aims to isolate acacetin, a flavonoid, from the aerial part of Z. clinopodioides, to develop an HPLC method for its detection, and to evaluate its protective effects on neonatal rat cardiomyocytes.
Methods
Sephadex LH-20 silicagel and pillar layer chromatography silica gel were applied for the isolation and purification of acacetin and its structure was elucidated on the basis of 1H and 13C NMR spectroscopy. The content of acacetin in Z. clinopodioides collected from three different origins was determined by HPLC. The neonatal rat cardiomyocytes were isolated and cultured in vitro to establish a hypoxia/reoxygenation injury model. The viability of cardiomyocytes was measured by the MTT method. Changes of malondialdehyde (MDA) content in the medium were also determined.
Results
The acacetin content in various batches of Z. clinopodioides ranged from 45.50 to 47.41 μg/g. Acacetin of 25, 10, 5 μg/mL significantly decreased the MDA content in a model of hypoxia/reoxygenation injury (P < 0.001, P < 0.001 and P = 0.033, respectively).
Conclusions
Acacetin protects neonatal cardiomyocytes from the damage induced by hypoxia/reoxygenation stress through reduction of lipid peroxidation and enhancement of the antioxidant activity.
doi:10.1186/s13020-014-0028-3
PMCID: PMC4272544  PMID: 25558275
Acacetin; Ziziphora clinopodioides; Neonatal rat cardiomyocytes; Hypoxia/reoxygenation; HPLC
5.  Porcine Coronin 1A Contributes to Nuclear Factor-Kappa B (NF-κB) Inactivation during Haemophilus parasuis Infection 
PLoS ONE  2014;9(8):e103904.
Haemophilus parasuis (H.parasuis) is the etiological agent of porcine polyserositis and arthritis (Glässer's disease) characterized by fibrinous polyserositis, meningitis and polyarthritis, causing severe economic losses to the swine industry. Currently, the molecular basis of this infection is largely unkonwn. Coronin 1A (Coro1A) plays important roles in host against bacterial infection, yet little is known about porcine Coro1A. In this study, we investigated the molecular characterization of porcine Coro1A, revealing that porcine Coro1A was widely expressed in different tissues. Coro1A could be induced by lipopolysaccharide (LPS), polyinosinic acid-polycytidylic acid [poly (I:C)] and H.parasuis in porcine kidney-15 (PK-15) cells. Functional analyses revealed that porcine Coro1A suppressed the NF-κB activation during H.parasuis infection by inhibiting the degradation of IκBα and nuclear translocation of p65. Overexpression of porcine Coro1A inhibited the transcription of NF-κB-mediated downstream genes [Interleukin-6 (IL-6), Interleukin-8 (IL-8) and COX-2] through down-regulation of NF-κB. The results indicated that porcine Coro1A is an important immunity related gene that helps to inhibit NF-kB activation during H. parasuis infection.
doi:10.1371/journal.pone.0103904
PMCID: PMC4122374  PMID: 25093672
6.  Transcript Levels of Major Interleukins in Relation to the Clinicopathological Profile of Patients with Tuberculous Intervertebral Discs and Healthy Controls 
PLoS ONE  2014;9(6):e101324.
Objectives
The purpose of the present study was to simultaneously examine the transcript levels of a large number of interleukins (ILs; IL-9, IL-10, IL-12, IL-13, IL-16, IL-17, IL-18, IL-26, and IL-27) and investigate their correlation with the clinicopathological profiles of patients with tuberculous intervertebral discs.
Methods
Clinical data were collected from 150 patients participating in the study from January 2013 to December 2013. mRNA expression levels in 70 tuberculous, 70 herniated, and 10 control intervertebral disc specimens were determined by real-time polymerase chain reaction.
Results
IL-10, IL-16, IL-17, IL-18, and IL-27 displayed stronger expression in tuberculous spinal disc tissue than in normal intervertebral disc tissue (P<0.05). Our results illustrated multiple correlations among IL-10, IL-16, IL-17, IL-18, and IL-27 mRNA expression in tuberculous samples. Smoking habits were found to have a positive correlation with IL-17 transcript levels and a negative correlation with IL-10 transcript levels (P<0.05). Pain intensity, symptom duration, C-reactive protein levels, and the erythrocyte sedimentation rate exhibited multiple correlations with the transcript levels of several ILs (P<0.05).
Conclusions
The experimental data imply a double-sided effect on the activity of ILs in tuberculous spinal intervertebral discs, suggesting that they may be involved in intervertebral discs destruction. Our findings also suggest that smoking may affect the intervertebral discs destruction process of spinal tuberculosis. However, further studies are necessary to elucidate the exact role of ILs in the intervertebral discs destruction process of spinal tuberculosis.
doi:10.1371/journal.pone.0101324
PMCID: PMC4074196  PMID: 24971599
7.  Heart rate changes in partial seizures: analysis of influencing factors among refractory patients 
BMC Neurology  2014;14:135.
Background
We analyzed the frequency of heart rate (HR) changes related to seizures, and we sought to identify the influencing factors of these changes during partial seizures, to summarize the regularity of the HR changes and gain some insight into the mechanisms involved in the neuronal regulation of cardiovascular function. To date, detailed information on influencing factors of HR changes related to seizures by multiple linear regression analysis remains scarce.
Methods
Using video-electroencephalograph (EEG)-electrocardiograph (ECG) recordings, we retrospectively assessed the changes in the HR of 81 patients during a total of 181 seizures, including 27 simple partial seizures (SPS), 110 complex partial seizures (CPS) and 44 complex partial seizures secondarily generalized (CPS-G). The epileptogenic focus and the seizure type, age, gender, and sleep/wakefulness state of each patient were evaluated during and after the seizure onset. The HR changes were evaluated in the stage of epilepsy as time varies.
Results
Of the 181 seizures from 81 patients with ictal ECGs, 152 seizures (83.98%) from 74 patients were accompanied by ictal tachycardia (IT). And only 1 patient was accompanied by ictal bradycardia (IB). A patient has both IT and IB. We observed that HR difference was independently correlated with side, type and sleep/wakefulness state. In this analysis, the HR changes were related to the side, gender, seizure type, and sleep/wakefulness state. Right focus, male, sleep, and CPS-G showed more significant increases than that were observed in left, female, wakefulness, SPS and CPS. HR increases rapidly within 10 seconds before seizure onset and ictus, and typically slows to normal with seizure offset.
Conclusion
CPS-G, sleep and right focus led to higher ictal HR. The HR in the stage of epilepsy has regularly been observed to change to become time-varying. The risk factors of ictal HR need to be controlled along with sleep, CPS-G and right focus. Our study first explains that the HR in seizures has a regular evolution varying with time. Our study might help to further clarify the basic mechanisms of interactions between heart and brain, making seizure detection and closed-loop systems a possible therapeutic alternative in refractory patients.
doi:10.1186/1471-2377-14-135
PMCID: PMC4080606  PMID: 24950859
Partial seizures; HR changes; Video-EEG-ECG; Influence factors
8.  CXCL12-CXCR4 axis promotes the natural selection of breast cancer cell metastasis 
Tumour Biology  2014;35(8):7765-7773.
CXCR4 and its ligand CXCL12 can promote the proliferation, survival, and invasion of cancer cells. They have been shown to play an important role in regulating metastasis of breast cancer to specific organs. High CXCR4 expression was also correlated to poor clinical outcome. Previous study also showed that tumor cells express a high level of CXCR4 and that tumor metastasis target tissues (lung, liver, and bone) express high levels of the ligand CXCL12, allowing tumor cells to directionally migrate to target organs via a CXCL12-CXCR4 chemotactic gradient. However, the exact mechanisms of how CXCR4 and CXCL12 enhance metastasis and/or tumor growth and their full implications on breast cancer progression are unknown. Yet it is likely that chemokine receptor signaling may provide more than just a migrational advantage by also helping the metastasized cells establish and survive in secondary environments. In this study, we investigated CXCR4 and CXCL12 expression in breast cancer and analyzed its association with clinicopathological factors by immunohistochemistry first. Then, we detected the mRNA and protein expression of CXCR4 and CXCL12 in breast cancer cell lines by Western blot and RT-PCR. The MDA-MB-231 has CXCR4 expression and very weak CXCL12 expression. So, we constructed the functional CXCL12 expression in MDA-MB-231 using a gene transfection technique. Further experiments were conducted to evaluate the effect of CXCL12 transfection on the biological behaviors of MDA-MB-231. The cell proliferation of MDA-MB-231–CXCL12 was accessed by MTT assay; the apoptosis was analyzed by an AnnexinV-FITC/propidium iodide double staining of flow cytometry method; and the cell invasive ability was examined by Matrigel invasion assay. Immunohistochemical analysis showed the co-expression of CXCR4 and CXCL12 correlated with lymph node metastasis and TNM stage (p < 0.01). It suggested that the chemokine CXCL12 and its sole ligand CXCR4 play important role in the malignance of breast cancer. To gain a deeper insight into it, we picked CXCR4-expressing cells MDA-MB-231 to be transfected with CXCL12 stably. The decreased cellular proliferation, increased apoptosis, and invasive ability were found in MDA-MB-231 with successful CXCL12 transfection (p < 0.05). Our findings underlined the CXCL12-CXCR4 axis correlated tightly with breast cancer metastasis. CXCL12-CXCR4 axis can increase the invasion and apoptosis of MDA-MB-231 simultaneously. These data strongly support the hypothesis that CXCL12-CXCR4 axis promotes the natural selection of breast cancer cell metastasis. Our findings could have significant implications in terms of breast cancer aggressiveness and the effectiveness of targeting the receptors and downstream signaling pathways for the treatment of breast cancer.
doi:10.1007/s13277-014-1816-1
PMCID: PMC4158177  PMID: 24810923
CXCR4; CXCL12; Breast cancer
9.  Stability and Synchronization for Discrete-Time Complex-Valued Neural Networks with Time-Varying Delays 
PLoS ONE  2014;9(4):e93838.
In this paper, the synchronization problem for a class of discrete-time complex-valued neural networks with time-varying delays is investigated. Compared with the previous work, the time delay and parameters are assumed to be time-varying. By separating the real part and imaginary part, the discrete-time model of complex-valued neural networks is derived. Moreover, by using the complex-valued Lyapunov-Krasovskii functional method and linear matrix inequality as tools, sufficient conditions of the synchronization stability are obtained. In numerical simulation, examples are presented to show the effectiveness of our method.
doi:10.1371/journal.pone.0093838
PMCID: PMC3979734  PMID: 24714386
10.  Developmental origins of brain tumors 
Current opinion in neurobiology  2012;22(5):844-849.
Brain tumors are devastating due to the high fatality rate and the devastating impact on life qualities of patients. Recent advancement of comparative transcriptome profiling tools and mouse genetic models has greatly deepened our understanding of the developmental origins of these tumors, which could lead to effective therapeutic strategies. We review recent progresses in three types of brain tumors: ependymoma, medulloblastoma, and malignant glioma. The conceptual framework established by these studies converged on three important aspects. First, subtypes in each tumor group originate from distinct cell types. Second, each cell-of-origin is uniquely sensitive to some but not other genetic mutations. Lastly, mutant stem cells may not transform until they differentiate into more restricted progenitor cell type. Overall, these findings indicate the existence of intricate interactions between gene mutations and developmental context for the formation of brain tumors.
doi:10.1016/j.conb.2012.04.012
PMCID: PMC3432164  PMID: 22560511
11.  A Macaque Model of Mesial Temporal Lobe Epilepsy Induced by Unilateral Intrahippocampal Injection of Kainic Acid 
PLoS ONE  2013;8(8):e72336.
Objective
In order to better investigate the cause/effect relationships of human mesial temporal lobe epilepsy (mTLE), we hereby describe a new non-human primate model of mTLE.
Methods
Ten macaques were studied and divided into 2 groups: saline control group (n = 4) and kainic acid (KA) injection group (n = 6). All macaques were implanted bilaterally with subdural electrodes over temporal cortex and depth electrodes in CA3 hippocampal region. KA was stereotaxically injected into the right hippocampus of macaques. All animals were monitored by video and electrocorticography (ECoG) to assess status epilepticus (SE) and subsequent spontaneous recurrent seizures (SRS). Additionally, in order to evaluate brain injury produced by SE or SRS, we used both neuroimaging, including magnetic resonance image (MRI) & magnetic resonance spectroscopy (MRS), and histological pathology, including Nissl stainning and glial fibrillary acid protein (GFAP) immunostaining.
Results
The typical seizures were observed in the KA-injected animal model. Hippocampal sclerosis could be found by MRI & MRS. Hematoxylin and eosin (H&E) staining and GFAP immunostaining showed neuronal loss, proliferation of glial cells, formation of glial scars, and hippocampal atrophy. Electron microscopic analysis of hippocampal tissues revealed neuronal pyknosis, partial ribosome depolymerization, an abnormal reduction in rough endoplasmic reticulum size, expansion of Golgi vesicles and swollen star-shaped cells. Furthermore, we reported that KA was able to induce SE followed by SRS after a variable period of time. Similar to human mTLE, brain damage is confined to the hippocampus. Accordingly, hippocampal volume is in positive correlations with the neuronal cells count in the CA3, especially the ratio of neuron/glial cell.
Conclusions
The results suggest that a model of mTLE can be developed in macaques by intra-hippocampal injection of KA. Brain damage is confined to the hippocampus which is similar to the human mTLE. The hippocampal volume correlates with the extension of the hippocampal damage.
doi:10.1371/journal.pone.0072336
PMCID: PMC3753347  PMID: 23991095
12.  Neaumycin - A New Macrolide from Streptomyces sp. NEAU-x211 
Organic Letters  2012;14(5):1254-1257.
Neaumycin, a new 30-membered macrolide featuring an internal diester bridge, a molecular architecture that is unprecedented among known macrolide natural products, was isolated from a soil actinomycete strain Streptomyces sp. neau-x211. The structure of neaumycin was elucidated on the basis of comprehensive mass and NMR spectroscopic interpretation, including the relative stereochemistry of four independent coupling systems.
doi:10.1021/ol300074d
PMCID: PMC3293494  PMID: 22332843
13.  Mosaic Analysis with Double Markers (MADM) Reveals Tumor Cell-of-Origin in Glioma 
Cell  2011;146(2):209-221.
SUMMARY
Cancer cell-of-origin is difficult to identify by analyzing cells within terminal-stage tumors, whose identity could be concealed by the acquired plasticity. Thus an ideal approach to identify the cell-of-origin is to analyze proliferative abnormalities in distinct lineages prior to malignancy. Here we use Mosaic Analysis with Double Markers (MADM) in mice to model gliomagenesis by initiating concurrent p53/Nf1 mutations sporadically in neural stem cells (NSCs). Surprisingly, MADM-based lineage tracing revealed significant aberrant growth prior to malignancy only in oligodendrocyte precursor cells (OPCs), but not in any other NSC-derived lineages or NSCs themselves. Upon tumor formation, phenotypic and transcriptome analyses of tumor cells revealed salient OPC features. Finally, introducing the same p53/Nf1 mutations directly into OPCs consistently led to gliomagenesis. Our findings suggest OPCs as the cell-of-origin in this model even when initial mutations occur in NSCs, and highlight the importance of analyzing pre-malignant stages to identify the cancer cell-of-origin.
doi:10.1016/j.cell.2011.06.014
PMCID: PMC3143261  PMID: 21737130
14.  Combined administration of anisodamine and neostigmine produces anti-shock effects: involvement of α7 nicotinic acetylcholine receptors 
Acta Pharmacologica Sinica  2012;33(6):761-766.
Aim:
To evaluate the anti-effects of anisodamine and neostigmine in animal models of endotoxic and hemorrhagic shock.
Methods:
Kunming mice were injected with lipopolysaccharide (LPS 30 mg/kg, ip) to induce endotoxic shock. Anisodamine (12.5, 25, and 50 mg/kg, ip) and neostigmine (12.5, 25, and 50 μg/kg, ip) were administered immediately after LPS injection. Survival rate was monitored, and the serum levels of TNF-α and IL-1β were analyzed using ELISA assays. The effects of anisodamine and neostigmine were also examined in α7 nicotinic acetylcholine receptor (α7 nAChR) knockout mice with endotoxic shock and in Beagle dogs with hemorrhagic shock.
Results:
In mice with experimental endotoxemia, combined administration of anisodamine and neostigmine significantly increased the survival rate and decreased the serum levels of inflammatory cytokines, as compared to those produced by either drug alone. The anti-shock effect of combined anisodamine and neostigmine was abolished in α7 nAChR knockout mice. On the other hand, intravenous injection of the combined anisodamine and neostigmine, or the selective α7 nAChR agonist PNU282987 exerted similar anti-shock effects in dogs with hemorrhagic shock.
Conclusion:
The results demonstrate that combined administration of anisodamine and neostigmine produces significant anti-shock effects, which involves activation of α7 nAChRs.
doi:10.1038/aps.2012.26
PMCID: PMC4010367  PMID: 22580739
anisodamine; neostigmine; PNU282987; α7 nicotinic acetylcholine receptor; endotoxic shock; hemorrhagic shock
15.  Transcription analysis on response of porcine alveolar macrophages to Haemophilus parasuis 
BMC Genomics  2012;13:68.
Background
Haemophilus parasuis (H. parasuis) is the etiological agent of Glässer's disease in pigs. Currently, the molecular basis of this infection is largely unknown. The innate immune response is the first line of defense against the infectious disease. Systematical analysis on host innate immune response to the infection is important for understanding the pathogenesis of the infectious microorganisms.
Results
A total of 428 differentially expressed (DE) genes were identified in the porcine alveolar macrophages (PAMs) 6 days after H. parasuis infection. These genes were principally related to inflammatory response, immune response, microtubule polymerization, regulation of transcript and signal transduction. Through the pathway analysis, the significant pathways mainly concerned with cell adhesion molecules, cytokine-cytokine receptor interaction, complement and coagulation cascades, toll-like receptor signaling pathway, MAPK signaling pathway, suggesting that the host took different strategies to activate immune and inflammatory response upon H. parasuis infection. The global interactions network and two subnetworks of the proteins encoded by DE genes were analyzed by using STRING. Further immunostimulation analysis indicated that mRNA levels of S100 calcium-binding protein A4 (S100A4) and S100 calcium-binding protein A6 (S100A6) in porcine PK-15 cells increased within 48 h and were sustained after administration of lipopolysaccharide (LPS) and Poly (I:C) respectively. The s100a4 and s100a6 genes were found to be up-regulated significantly in lungs, spleen and lymph nodes in H. parasuis infected pigs. We firstly cloned and sequenced the porcine coronin1a gene. Phylogenetic analysis showed that poCORONIN 1A belonged to the group containing the Bos taurus sequence. Structural analysis indicated that the poCORONIN 1A contained putative domains of Trp-Asp (WD) repeats signature, Trp-Asp (WD) repeats profile and Trp-Asp (WD) repeats circular profile at the N-terminus.
Conclusions
Our present study is the first one focusing on the response of porcine alveolar macrophages to H. parasuis. Our data demonstrate a series of genes are activated upon H. parasuis infection. The observed gene expression profile could help screening the potential host agents for reducing the prevalence of H. parasuis and further understanding the molecular pathogenesis associated with H. parasuis infection in pigs.
doi:10.1186/1471-2164-13-68
PMCID: PMC3296652  PMID: 22330747
16.  Isolation and Characterization of Shigella flexneri G3, Capable of Effective Cellulosic Saccharification under Mesophilic Conditions ▿ †  
A novel Shigella strain (Shigella flexneri G3) showing high cellulolytic activity under mesophilic, anaerobic conditions was isolated and characterized. The bacterium is Gram negative, short rod shaped, and nonmotile and displays effective production of glucose, cellobiose, and other oligosaccharides from cellulose (Avicel PH-101) under optimal conditions (40°C and pH 6.5). Approximately 75% of the cellulose was hydrolyzed in modified ATCC 1191 medium containing 0.3% cellulose, and the oligosaccharide production yield and specific production rate reached 375 mg g Avicel−1 and 6.25 mg g Avicel−1 h−1, respectively, after a 60-hour incubation. To our knowledge, this represents the highest oligosaccharide yield and specific rate from cellulose for mesophilic bacterial monocultures reported so far. The results demonstrate that S. flexneri G3 is capable of rapid conversion of cellulose to oligosaccharides, with potential biofuel applications under mesophilic conditions.
doi:10.1128/AEM.01230-10
PMCID: PMC3020557  PMID: 21097577
17.  Beneficial Effects of Anisodamine in Shock Involved Cholinergic Anti-Inflammatory Pathway 
Anisodamine, an antagonist of muscarinic receptor, has been used therapeutically to improve blood flow in circulatory disorders such as septic shock in China since 1965. The main mechanism of anisodamine for anti-shock proposed in Pharmacology for Chinese medical students is to improve blood flow in the microcirculation. Here, we suggest a new mechanism for its anti-shock effect. That is, anisodamine, by blocking muscarinic receptor, results in rerouting of acetylcholine to α7 nicotinic acetylcholine receptor (α7nAChR) bringing about increased acetylcholine-mediated activation of α7nAChR and the cholinergic anti-inflammatory pathway.
doi:10.3389/fphar.2011.00023
PMCID: PMC3108475  PMID: 21687515
anisodamine; acetylcholine; α7nAChR; inflammation; shock
18.  Genome Sequence of the Milbemycin-Producing Bacterium Streptomyces bingchenggensis▿  
Journal of Bacteriology  2010;192(17):4526-4527.
Streptomyces bingchenggensis is a soil-dwelling bacterium producing the commercially important anthelmintic macrolide milbemycins. Besides milbemycins, the insecticidal polyether antibiotic nanchangmycin and some other antibiotics have also been isolated from this strain. Here we report the complete genome sequence of S. bingchenggensis. The availability of the genome sequence of S. bingchenggensis should enable us to understand the biosynthesis of these structurally intricate antibiotics better and facilitate rational improvement of this strain to increase their titers.
doi:10.1128/JB.00596-10
PMCID: PMC2937363  PMID: 20581206
19.  Role of vascular KATP channels in blood pressure variability after sinoaortic denervation in rats 
Acta Pharmacologica Sinica  2011;32(2):194-200.
Aim:
To investigate the role of ATP-sensitive potassium (KATP) channels on blood pressure variability (BPV) in sinoaortic denervated (SAD) rats.
Methods:
SAD was performed on male Sprague-Dawley rats 4 weeks before the study. mRNA expression of Kir6.1, Kir6.2 and SUR2 in aorta and mesenteric artery was determined using real-time quantitative polymerase chain reaction, and confirmed at the protein level using Western blotting and laser confocal immunofluorescence assays. Concentration-response curves of isolated aortic and mesenteric arterial rings to adenosine and pinacidil were established. Effects of KATP channel openers and blocker on BPV were examined in conscious SAD rats.
Results:
Aortic SUR2 expression was significantly greater, while Kir6.1 was lower, in SAD rats than in sham-operated controls. In contrast, in the mesenteric artery both SUR2 and Kir6.1 expression were markedly lower in SAD rats than controls. For both arteries, Kir6.2 expression was indistinguishable between sham-operated and SAD rats. These findings were confirmed at the protein level. Responses of the aorta to both adenosine and pinacidil were enhanced after SAD, while the mesenteric response to adenosine was attenuated. Pinacidil, diazoxide, nicorandil, and glibenclamide significantly decreased BPV.
Conclusion:
These findings indicate that expression of vascular KATP channels is altered by chronic SAD. These alterations influence vascular reactivity, and may play a role in the increased BPV in chronic SAD rats.
doi:10.1038/aps.2010.195
PMCID: PMC4009933  PMID: 21293472
ATP-sensitive potassium channels; blood pressure variability; sinoaotic denervation
20.  Fatal Avian Influenza (H5N1) Infection in Human, China 
Emerging Infectious Diseases  2010;16(11):1799-1801.
doi:10.3201/eid1611.090212
PMCID: PMC3294501  PMID: 21029551
Viruses; avian influenza; influenza-like illnesses; respiratory infections; poultry; H5N1; China; letter
21.  Calcium-sensing receptors regulate cardiomyocyte Ca2+ signaling via the sarcoplasmic reticulum-mitochondrion interface during hypoxia/reoxygenation 
Communication between the SR (sarcoplasmic reticulum, SR) and mitochondria is important for cell survival and apoptosis. The SR supplies Ca2+ directly to mitochondria via inositol 1,4,5-trisphosphate receptors (IP3Rs) at close contacts between the two organelles referred to as mitochondrion-associated ER membrane (MAM). Although it has been demonstrated that CaR (calcium sensing receptor) activation is involved in intracellular calcium overload during hypoxia/reoxygenation (H/Re), the role of CaR activation in the cardiomyocyte apoptotic pathway remains unclear. We postulated that CaR activation plays a role in the regulation of SR-mitochondrial inter-organelle Ca2+ signaling, causing apoptosis during H/Re. To investigate the above hypothesis, cultured cardiomyocytes were subjected to H/Re. We examined the distribution of IP3Rs in cardiomyocytes via immunofluorescence and Western blotting and found that type 3 IP3Rs were located in the SR. [Ca2+]i, [Ca2+]m and [Ca2+]SR were determined using Fluo-4, x-rhod-1 and Fluo 5N, respectively, and the mitochondrial membrane potential was detected with JC-1 during reoxygenation using laser confocal microscopy. We found that activation of CaR reduced [Ca2+]SR, increased [Ca2+]i and [Ca2+]m and decreased the mitochondrial membrane potential during reoxygenation. We found that the activation of CaR caused the cleavage of BAP31, thus generating the pro-apoptotic p20 fragment, which induced the release of cytochrome c from mitochondria and the translocation of bak/bax to mitochondria. Taken together, these results reveal that CaR activation causes Ca2+ release from the SR into the mitochondria through IP3Rs and induces cardiomyocyte apoptosis during hypoxia/reoxygenation.
doi:10.1186/1423-0127-17-50
PMCID: PMC2908572  PMID: 20565791
22.  Changes in intestinal mucosal immune barrier in rats with endotoxemia 
AIM: To investigate the dysfunction of the immunological barrier of the intestinal mucosa during endotoxemia and to elucidate the potential mechanism of this dysfunction.
METHODS: Male Wistar rats were randomly distributed into two groups: control group and lipopolysaccharide (LPS) group. Endotoxemia was induced by a single caudal venous injection of LPS. Animals were sacrificed in batches 2, 6, 12 and 24 h after LPS infusion. The number of microfold (M)-cells, dendritic cells (DCs), CD4+ T cells, CD8+ T cells, regulatory T (Tr) cells and IgA+ B cells in the intestinal mucosa were counted after immunohistochemical staining. Apoptotic lymphocytes were counted after TUNEL staining. The levels of interleukin (IL)-4, interferon (IFN)-γ and forkhead box P3 (Foxp3) in mucosal homogenates were measured by ELISA. The secretory IgA (sIgA) content in the total protein of one milligram of small intestinal mucus was detected using a radioimmunological assay.
RESULTS: This research demonstrated that LPS-induced endotoxemia results in small intestinal mucosa injury. The number of M-cells, DCs, CD8+ T cells, and IgA+ B cells were decreased while Tr cell and apoptotic lymphocyte numbers were increased significantly. The number of CD4+ T cells increased in the early stages and then slightly decreased by 24 h. The level of IL-4 significantly increased in the early stages and then reversed by the end of the study period. The level of IFN-γ increased slightly in the early stages and then decreased markedly by the 24 h time point. Level of Foxp3 increased whereas sIgA level decreased.
CONCLUSION: Mucosal immune dysfunction forms part of the intestinal barrier injury during endotoxemia. The increased number and function of Tr cells as well as lymphocyte apoptosis result in mucosal immunodeficiency.
doi:10.3748/wjg.15.5843
PMCID: PMC2791279  PMID: 19998507
Endotoxemia; Rats; Intestinal mucosa; Immunity
23.  catena-Poly[[[tetra­aqua­cobalt(II)]-μ-4,4′-bipyridine-κ2 N:N′] 2-[4-(2-carboxyl­ato­eth­yl)phen­oxy]acetate] 
In the title complex, {[Co(C10H8N2)(H2O)4](C11H10O5)}n, the unique CoII ion lies on an inversion center and is coordinated by two N atoms from two 4,4′-bipyridine ligands and four O atoms from four water mol­ecules in a slightly distorted octa­hedral coordination geometry. The 4,4′-bipyridine ligands bridge CoII ions into a one-dimensional chain structure. In the crystal structure, inter­molecular O—H⋯O hydrogen bonds link cations and anions into a three-dimensional network. The dianions are completely disordered about an inversion center.
doi:10.1107/S1600536809021552
PMCID: PMC2969250  PMID: 21582697
24.  Poly[μ-5-ammonio­isophthalato-aqua-μ-oxalato-dysprosium(III)] 
The title complex, [Dy(C8H6NO4)(C2O4)(H2O)]n, is a dysprosium coordination polymer with mixed anions and was obtained under hydrothermal conditions. In the structure, the oxalate and 5-amino­isophthalate ligands link the dysprosium ions, building up a two-dimensional metal–organic framework parallel to the (10) plane. These sheets are further connected through O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds, forming a three-dimensional supra­molecular structure.
doi:10.1107/S1600536809019199
PMCID: PMC2969203  PMID: 21582687
25.  Effects of Anode Flow Field Design on CO2 Bubble Behavior in μDMFC 
Sensors (Basel, Switzerland)  2009;9(5):3314-3324.
Clogging of anode flow channels by CO2 bubbles is a vital problem for further performance improvements of the micro direct methanol fuel cell (μDMFC). In this paper, a new type anode structure using the concept of the non-equipotent serpentine flow field (NESFF) to solve this problem was designed, fabricated and tested. Experiments comparing the μDMFC with and without this type of anode flow field were implemented using a home-made test loop. Results show that the mean-value, amplitude and frequency of the inlet-to-outlet pressure drops in the NESFF is far lower than that in the traditional flow fields at high μDMFC output current. Furthermore, the sequential images of the CO2 bubbles as well as the μDMFC performance with different anode flow field pattern were also investigated, and the conclusions are in accordance with those derived from the pressure drop experiments. Results of this study indicate that the non-equipotent design of the μDMFC anode flow field can effectively mitigate the CO2 clogging in the flow channels, and hence lead to a significant promotion of the μDMFC performance.
doi:10.3390/s90503314
PMCID: PMC3297162  PMID: 22412313
μDMFC; flow field; pressure drop; CO2 bubbles

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