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1.  Renoprotective effects of olmesartan medoxomil on diabetic nephropathy in streptozotocin-induced diabetes in rats 
Biomedical Reports  2013;2(1):24-28.
Olmesartan medoxomil (OM) is one of the newest members of the angiotensin receptor blocker (ARB) family. The renoprotective effects of the angiotensin II type 1 receptor antagonist OM was investigated in a streptozotocin (STZ)-induced diabetic rat model. In this study, we investigated whether OM was able to ameliorate diabetic nephropathy (DN). Thirty male Sprague Dawley rats were assigned to 3 groups: the non-diabetic (group A, n=10), the untreated STZ-induced DN control (group B, n=10) and the STZ-induced DN treated with OM (group C, n=10). Blood pressure (BP) and glucose, creatinine (Cr), blood urea nitrogen (BUN), superoxide dismutase (SOD), malondialdehyde (MDA) microalbumin and urinary protein concentrations were measured. In STZ diabetic rats, BP, glucose, Cr, BUN, MDA and urinary protein levels were significantly increased compared to the non-diabetic control group. OM significantly improved the biological indices in the DN rats. The renal pathological changes were also observed under a light microscope. Our results suggested that OM exerted renoprotective effects on rats with STZ-induced diabetes.
PMCID: PMC3917007  PMID: 24649063
renoprotective effects; olmesartan medoxomil; diabetic nephropathy
2.  An Essential Role for Heat Shock Transcription Factor Binding Protein 1 (HSBP1) During Early Embryonic Development 
Developmental biology  2013;386(2):448-460.
Heat shock factor binding protein 1 (HSBP1) is a 76 amino acid polypeptide that contains two arrays of hydrophobic heptad repeats and was originally identified through its interaction with the oligomerization domain of heat shock factor 1 (Hsf1), suppressing Hsf1’s transcriptional activity following stress. To examine the function of HSBP1 in vivo, we generated mice with targeted disruption of the hsbp1 gene and examined zebrafish embryos treated with HSBP1-specific morpholino oligonucleotides. Our results show that hsbp1 is critical for preimplantation embryonic development. Embryonic stem (ES) cells deficient in hsbp1 survive and proliferate normally into the neural lineage in vitro; however, lack of hsbp1 in embryoid bodies (EBs) leads to disorganization of the germ layers and a reduction in the endoderm-specific markers (such as α-fetoprotein). We further show that hsbp1-deficient mouse EBs and knockdown of HSBP1 in zebrafish leads to an increase in the expression of the neural crest inducers Snail2, Tfap2α and Foxd3, suggesting a potential role for HSBP1 in the Wnt pathway. The hsbp1-deficient ES cells, EBs and zebrafish embryos with reduced HSBP1 levels exhibit elevated levels of Hsf1 activity and expression of heat shock proteins (Hsps). We conclude that HSBP1 plays an essential role during early mouse and zebrafish embryonic development.
PMCID: PMC4114229  PMID: 24380799
HSBP1; knockout mice; embryonic stem cells; zebrafish; neural crest
3.  Chromatin modifications and genomic contexts linked to dynamic DNA methylation patterns across human cell types 
Scientific Reports  2015;5:8410.
DNA methylation is related closely to sequence contexts and chromatin modifications; however, their potential differences in different genomic regions across cell types remain largely unexplored. We used publicly available genome-scale DNA methylation and histone modification profiles to study their relationships among different genomic regions in human embryonic stem cells (H1), H1-derived neuronal progenitor cultured cells (NPC), and foetal fibroblasts (IMR90) using the Random forests classifier. Histone modifications achieved high accuracy in modelling DNA methylation patterns on a genome scale in the three cell types. The inclusion of sequence features helped improve accuracy only in non-promoter regions of IMR90. Furthermore, the top six feature combinations obtained by mean decrease Gini were important indicators of different DNA methylation patterns, suggesting that H3K4me2 and H3K4me3 are important indicators that are independent of genomic regions and cell types. H3K9me3 was IMR90-specific and exhibited a genomic region-specific correlation with DNA methylation. Variations of essential chromatin modification signals may effectively discriminate changes of DNA methylation between H1 and IMR90. Genes with different co-variations of epigenetic marks exhibited genomic region-specific biological relevance. This study provides an integrated strategy to identify systematically essential epigenetic and genetic elements of genomic region-specific and cell type-specific DNA methylation patterns.
PMCID: PMC4325317  PMID: 25673498
4.  BANF1 Is Downregulated by IRF1-Regulated MicroRNA-203 in Cervical Cancer 
PLoS ONE  2015;10(2):e0117035.
MicroRNAs (miRNAs) play important roles in various biological processes and are closely associated with the development of cancer. In fact, aberrant expression of miRNAs has been implicated in numerous cancers. In cervical cancer, miR-203 levels are decreased, although the cause of this aberrant expression remains unclear. In this study, we investigate the molecular mechanisms regulating miR-203 gene transcription. We identify the miR-203 transcription start site by 5’ rapid amplification of cDNA ends and subsequently identify the miR-203 promoter region. Promoter analysis revealed that IRF1, a transcription factor, regulates miR-203 transcription by binding to the miR-203 promoter. We also demonstrate that miR-203 targets the 3’ untranslated region of BANF1, thus downregulating its expression, whereas miR-203 expression is driven by IRF1. MiR-203 is involved in cell cycle regulation and overexpression of miR-203 suppresses cervical cancer cell proliferation, colony formation, migration and invasion. The inhibitory effect of miR-203 on the cancer cells is partially mediated by downregulating its target, BANF1, since knockdown of BANF1 also suppresses colony formation, migration and invasion.
PMCID: PMC4319761  PMID: 25658920
6.  Novel Numerical Characterization of Protein Sequences Based on Individual Amino Acid and Its Application 
BioMed Research International  2015;2015:909567.
The hydrophobicity and hydrophilicity of amino acids play a very important role in protein folding and its interaction with the environment and other molecules, as well as its catalytic mechanism. Based on the two physicochemical indexes, a 2D graphical representation of protein sequences is introduced; meanwhile, a new numerical characteristic has been proposed to compute the distance of different sequences for analysis of sequence similarity/dissimilarity on the basis of this graphical representation. Furthermore, we apply the new distance in the similarities/dissimilarities of ND5 proteins of nine species and predict the four major classes based on the dataset containing 639 domains. The results show that the method is simple and effective.
PMCID: PMC4332462
7.  Enhancement of Interferon Induction by ORF3 Product of Hepatitis E Virus 
Journal of Virology  2014;88(15):8696-8705.
Hepatitis E virus (HEV) causes both the endemic and epidemic spread of acute hepatitis in many parts of the world. HEV open reading frame 3 (ORF3) encodes a 13-kDa multifunctional protein (vp13) that is essential for HEV infection of animals. The exact role of vp13 in HEV infection remains unclear. In this study, vp13 was found to enhance interferon (IFN) production induced by poly(I · C), a synthetic analog of double-stranded RNA. Poly(I · C) treatment induced a higher level of IFN-β mRNA in HeLa cells stably expressing vp13 than in control cells. Using a luciferase reporter construct driven by the IFN-β promoter, we demonstrated that vp13 enhanced retinoic acid-inducible gene I (RIG-I)-dependent luciferase expression. This enhancement was found to be due to both an increased level of RIG-I protein and its activation. The levels of both endogenous and exogenous RIG-I were increased by vp13 by extension of the half-life of RIG-I. Additionally, vp13 interacts with the RIG-I N-terminal domain and enhances its K63-linked ubiquitination, which is essential for RIG-I activation. Analysis of vp13 deletion constructs suggested that the C-terminal domain of vp13 was essential for the enhancement of RIG-I signaling. In HEV-infected hepatoma cells, wild-type HEV led to a higher level of RIG-I and more poly(I · C)-induced IFN-β expression than did ORF3-null mutants. Analysis of vp13 from four HEV genotypes showed that vp13 from genotype I and III strains boosted RIG-I signaling, while vp13 from genotype II and IV strains had a minimal effect. These results indicate that vp13 enhances RIG-I signaling, which may play a role in HEV invasion.
IMPORTANCE Hepatitis E virus (HEV) is a significant pathogen causing hepatitis in many parts of the world, yet it is understudied compared with other viral hepatitis pathogens. Here we found that the HEV open reading frame 3 product, vp13, enhances interferon induction stimulated by a synthetic analog of double-stranded RNA. This enhancement may play a role in HEV invasion, as vp13 is essential for HEV infection in vivo. The results of this study provide insights into virus-cell interactions during HEV infection. In addition to revealing its possible roles in HEV interference with cellular signaling, these results suggest that the second half of the vp13 sequence can be ligated into the genomes of attenuated live viruses to induce an innate immune response for better protective immunity, as well as a marker for differentiation of vaccinated animals from those infected with the corresponding wild-type viruses.
PMCID: PMC4135948  PMID: 24850742
8.  Salvianolic Acids Attenuate Rat Hippocampal Injury after Acute CO Poisoning by Improving Blood Flow Properties 
BioMed Research International  2015;2015:526483.
Carbon monoxide (CO) poisoning causes the major injury and death due to poisoning worldwide. The most severe damage via CO poisoning is brain injury and mortality. Delayed encephalopathy after acute CO poisoning (DEACMP) occurs in forty percent of the survivors of acute CO exposure. But the pathological cause for DEACMP is not well understood. And the corresponding therapy is not well developed. In order to investigate the effects of salvianolic acid (SA) on brain injury caused by CO exposure from the view point of hemorheology, we employed a rat model and studied the dynamic of blood changes in the hemorheological and coagulative properties over acute CO exposure. Compared with the groups of CO and 20% mannitol + CO treatments, the severe hippocampal injury caused by acute CO exposure was prevented by SA treatment. These protective effects were associated with the retaining level of hematocrit (Hct), plasma viscosity, fibrinogen, whole blood viscosities and malondialdehyde (MDA) levels in red blood cells (RBCs). These results indicated that SA treatment could significantly improve the deformation of erythrocytes and prevent the damage caused by CO poisoning. Meanwhile, hemorheological indexes are good indicators for monitoring the pathological dynamic after acute CO poisoning.
PMCID: PMC4331406
9.  Evidence for high dispersal ability and mito-nuclear discordance in the small brown planthopper, Laodelphax striatellus 
Scientific Reports  2015;5:8045.
Understanding dispersal ability in pest species is critical for both theoretical aspects of evolutionary and population biology and from a practical standpoint, such as implementing effective forecasting systems. The small brown planthopper (SBPH), Laodelphax striatellus (Fallén), is an economically important pest, but few data exist on its dispersal ability. Here, we used mitochondrial and nuclear markers to elucidate the population genetic structure of SBPH and of the parasitic bacterium Wolbachia throughout temperate and subtropical China. Our results showed that the SBPH populations in China lack significant differences in genetic structure, suggesting extensive gene flow. Multilocus sequence typing revealed that Wolbachia infection was systematic and due to the same strain (wStri) within and across populations. However, the mtDNA haplogroups had a nonrandom distribution across the sampling localities, which correlated to latitudinal and climatic gradients. We explain this mito-nuclear discordance as a result of historical population recolonization or mitochondria adaptation to climate.
PMCID: PMC4309506  PMID: 25622966
11.  Evolutionary analysis of rubella viruses in mainland China during 2010–2012: endemic circulation of genotype 1E and introductions of genotype 2B 
Scientific Reports  2015;5:7999.
Rubella remains a significant burden in mainland China. In this report, 667 viruses collected in 24 of 31 provinces of mainland China during 2010–2012 were sequenced and analyzed, significantly extending previous reports on limited numbers of viruses collected before 2010. Only viruses of genotypes 1E and 2B were found. Genotype 1E viruses were found in all 24 provinces. Genotype 1E viruses were likely introduced into mainland China around 1997 and endemic transmission of primarily one lineage became established. Viruses reported here from 2010–2012 are largely in a single cluster within this lineage. Genotype 2B viruses were rarely detected in China prior to 2010. This report documents a previously undetected 2B lineage, which likely became endemic in eastern provinces of China between 2010 and 2012. Bayesian analyses were performed to estimate the evolutionary rates and dates of appearance of the genotype 1E and 2B viral linages in China. A skyline plot of viral population diversity did not provide evidence of reduction of diversity as a result of vaccination, but should be useful as a baseline for such reductions as vaccination programs for rubella become widespread in mainland China.
PMCID: PMC4303870  PMID: 25613734
12.  Hes1, an important gene for activation of hepatic stellate cells, is regulated by Notch1 and TGF-β/BMP signaling 
AIM: To determine the role of Notch1 and Hes1 in regulating the activation of hepatic stellate cells (HSCs) and whether Hes1 is regulated by transforming growth factor (TGF)/bone morphogenetic protein (BMP) signaling.
METHODS: Immunofluorescence staining was used to detect the expression of desmin, glial fibrillary acidic protein and the myofibroblastic marker α-smooth muscle actin (α-SMA) after freshly isolated, normal rat HSCs had been activated in culture for different numbers of days (0, 1, 3, 7 and 10 d). The expression of α-SMA, collagen1α2 (COL1α2), Notch receptors (Notch1-4), and the Notch target genes Hes1 and Hey1 were analyzed by reverse transcriptase-polymerase chain reaction. Luciferase reporter assays and Western blot were used to study the regulation of α-SMA, COL1α1, COL1α2 and Hes1 by NICD1, Hes1, CA-ALK3, and CA-ALK5 in HSC-T6 cells. Moreover, the effects of inhibiting Hes1 function in HSC-T6 cells using a Hes1 decoy were also investigated.
RESULTS: The expression of Notch1 and Hes1 mRNAs was significantly down-regulated during the culture of freshly isolated HSCs. In HSC-T6 cells, Notch1 inhibited the promoter activities of α-SMA, COL1α1 and COL1α2. On the other hand, Hes1 enhanced the promoter activities of α-SMA and COL1α2, and this effect could be blocked by inhibiting Hes1 function with a Hes1 decoy. Furthermore, co-transfection of pcDNA3-CA-ALK3 (BMP signaling activin receptor-like kinase 3) and pcDNA3.1-NICD1 further increased the expression of Hes1 compared with transfection of either vector alone in HSC-T6 cells, while pcDNA3-CA-ALK5 (TGF-β signaling activin receptor-like kinase 5) reduced the effect of NICD1 on Hes1 expression.
CONCLUSION: Selective interruption of Hes1 or maintenance of Hes1 at a reasonable level decreases the promoter activities of α-SMA and COL1α2, and these conditions may provide an anti-fibrotic strategy against hepatic fibrosis.
PMCID: PMC4299340  PMID: 25624721
Hes1; Notch1; TGF-β/BMP; Hepatic stellate cells; Hepatic fibrosis
13.  Novel Modifications on C-terminal Domain of RNA Polymerase II can Fine-tune the Phosphatase Activity of Ssu72 
ACS chemical biology  2013;8(9):2042-2052.
The C-terminal domain of RNA polymerase II (CTD) modulates the process of transcription through sequential phosphorylation/dephosphorylation of its heptide repeats through which it recruits various transcription regulators. Ssu72 is the first characterized cis-specific CTD phosphatase that dephosphorylates Ser5 with a requirement for the adjacent Pro6 in a cis conformation. The recent discovery of Thr4 phosphorylation in the CTD calls into question whether such a modification can interfere with Ssu72 binding via the elimination of a conserved intra-molecular hydrogen bond in the CTD that is potentially essential for recognition. To test if Thr4 phosphorylation will abolish Ser5 dephosphorylation by Ssu72, we determined the kinetic and structural properties of Drosophila Ssu72-symplekin in complex with the CTD peptide with consecutive phosphorylated Thr4 and Ser5. Our mass spectrometric and kinetic data established that Ssu72 doesn’t dephosphorylate Thr4, but the existence of phosphoryl-Thr4 next to Ser5 reduces the activity of Ssu72 towards the CTD peptide by four fold. To our surprise, even though the intra-molecular hydrogen bond is eliminated due to the phosphorylation of Thr4, the CTD adopts an almost identical conformation to be recognized by Ssu72 with Ser5 phosphorylated alone or both Thr4/Ser5 phosphorylated. Our results indicate that Thr4 phosphorylation will not abolish the essential Ssu72 activity, which is needed for cell survival. Instead, the phosphatase activity of Ssu72 is fine-tuned by Thr4 phosphorylation and eventually may lead to changes in transcription. Overall, we report the first case of structural and kinetic effects of phosphorylated Thr4 on CTD modifying enzymes. Our results support a model in which a combinatorial cascade of CTD modification can modulate transcription.
PMCID: PMC4296584  PMID: 23844594
Ssu72 phosphatase; phosphorylation of RNA polymerase II; transcription regulation; CTD code; post-translational modification; intra-molecular hydrogen bond; x-ray crystallography
14.  Effect of Hydrocarbon Chain Length in 1,2-Alkanediols on Percutaneous Absorption of Metronidazole: Toward Development of a General Vehicle for Controlled Release 
AAPS PharmSciTech  2014;15(2):354-363.
The objective of the present study is to investigate the effect of hydrocarbon chain length in 1,2-alkanediols on percutaneous absorption of metronidazole (MTZ). Twelve formulations (1,2-propanediol, 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol in 4% concentration, 1,2-hexanediol, and 1,2-heptanediol in 1% concentration, in the absence and presence of 1,4-cyclohexanediol, respectively) were studied in an in vitro hairless mouse skin model using Franz diffusion cell. Based on the flux values and retardation ratios (RR), a penetration retardation effect on percutaneous absorption of MTZ was observed for the formulations containing 1,2-diols having six- to seven-carbon chain in the presence of 1,4-cyclohexanediol (1,2-hexanediol with chain length of six hydrocarbons, RRs are 0.69 and 0.76 in the concentration of 4% and 1%, respectively; 1,2-heptanediol with chain length of seven hydrocarbons, RR is 0.78 in the concentration of 1%). On the other hand, no retardation effect was observed in formulations containing short alkyl chains (RRs of 1,2-propanediol, 1,2-butanediol, and 1,2-pentanediol are 0.99, 1.61, and 0.96, respectively). Instead, a penetration enhancement effect was observed for 1,2-diols having four and five carbons. In other words, effect of 1,2-alkanediols on percutaneous absorption of MTZ can be systematically modulated by simply varying number of –CH2 groups in the hydrocarbon chain—from being a penetration enhancer to retardant. These observations shed light on mechanism of the penetration enhancement and retardation effect and provide insight into rational design of penetration enhancers and retardants. Furthermore, the combination of 1,2-alkanediols and 1,4-cyclohexanediol could become a general vehicle for controlled release of pharmaceutical and cosmetic active ingredients.
PMCID: PMC3969481  PMID: 24395400
1,2-alkanediols; controlled release; hydrocarbon chain length; skin penetration
15.  Toll-interacting protein (Tollip) negatively regulates pressure overload-induced ventricular hypertrophy in mice 
Cardiovascular Research  2013;101(1):87-96.
Toll-interacting protein (Tollip) is a critical regulator of the Toll-like receptor-mediated signalling pathway. However, the role of Tollip in chronic pressure overload-induced cardiac hypertrophy remains unclear. This study aimed to determine the functional significance of Tollip in the regulation of aortic banding-induced cardiac remodelling and its underlying mechanisms.
Methods and results
First, we observed that Tollip was down-regulated in human failing hearts and murine hypertrophic hearts, as determined by western blotting and RT–PCR. Using cultured neonatal rat cardiomyocytes, we found that adenovirus vector-mediated overexpression of Tollip limited angiotensin II-induced cell hypertrophy; whereas knockdown of Tollip by shRNA exhibited the opposite effects. We then generated a transgenic (TG) mouse model with cardiac specific-overexpression of Tollip and subjected them to aortic banding (AB) for 8 weeks. When compared with AB-treated wild-type mouse hearts, Tollip-TGs showed a significant attenuation of cardiac hypertrophy, fibrosis, and dysfunction, as measured by echocardiography, immune-staining, and molecular/biochemical analysis. Conversely, a global Tollip-knockout mouse model revealed an aggravated cardiac hypertrophy and accelerated maladaptation to chronic pressure overloading. Mechanistically, we discovered that Tollip interacted with AKT and suppressed its downstream signalling pathway. Pre-activation of AKT in cardiomyocytes largely offset the Tollip-elicited anti-hypertrophic effects.
Our results provide the first evidence that Tollip serves as a negative regulator of pathological cardiac hypertrophy by blocking the AKT signalling pathway.
PMCID: PMC3968303  PMID: 24285748
Tollip; Cardiac remodelling; Pressure overload; AKT; Cardiomyocyte hypertrophy
16.  BBS mutations modify phenotypic expression of CEP290-related ciliopathies 
Human Molecular Genetics  2013;23(1):40-51.
Ciliopathies are a group of heterogeneous disorders associated with ciliary dysfunction. Diseases in this group display considerable phenotypic variation within individual syndromes and overlapping phenotypes among clinically distinct disorders. Particularly, mutations in CEP290 cause phenotypically diverse ciliopathies ranging from isolated retinal degeneration, nephronophthisis and Joubert syndrome, to the neonatal lethal Meckel–Gruber syndrome. However, the underlying mechanisms of the variable expressivity in ciliopathies are not well understood. Here, we show that components of the BBSome, a protein complex composed of seven Bardet–Biedl syndrome (BBS) proteins, physically and genetically interact with CEP290 and modulate the expression of disease phenotypes caused by CEP290 mutations. The BBSome binds to the N-terminal region of CEP290 through BBS4 and co-localizes with CEP290 to the transition zone (TZ) of primary cilia and centriolar satellites in ciliated cells, as well as to the connecting cilium in photoreceptor cells. Although CEP290 still localizes to the TZ and connecting cilium in BBSome-depleted cells, its localization to centriolar satellites is disrupted and CEP290 appears to disperse throughout the cytoplasm in BBSome-depleted cells. Genetic interactions were tested using Cep290rd16- and Bbs4-null mutant mouse lines. Additional loss of Bbs4 alleles in Cep290rd16/rd16 mice results in increased body weight and accelerated photoreceptor degeneration compared with mice without Bbs4 mutations. Furthermore, double-heterozygous mice (Cep290+/rd16;Bbs4+/−) have increased body weight compared with single-heterozygous animals. Our data indicate that genetic interactions between BBSome components and CEP290 could underlie the variable expression and overlapping phenotypes of ciliopathies caused by CEP290 mutations.
PMCID: PMC3857943  PMID: 23943788
17.  Effects and Mechanism of Baicalin on Apoptosis of Cervical Cancer HeLa Cells In-vitro 
The objective of this study was to observe the apoptosis-inducing effect and mechanism of baicalin on human cervical cancer HeLa cells. The inhibitory effect of baicalin on the growth of HeLa cells was measured by MTT assay, and cell proliferation and migration was analyzed by cell scratch assay. Morphological changes of apoptotic cells were viewed by the light microscope and electron microscope, and cell growth arrest was confirmed by flow cytometry. Moreover, Western blot was used for investigating the expression of apoptosis related proteins; spectrophotometry was used to examine Caspase-3 activation. Our results showed that baicalin could inhibit the proliferation of HeLa Cells via induction of apoptosis in a time and dose-dependent manner (P<0.01). Apoptotic signaling induced by baicalin was characterized by up-regulating Bax, Fas, FasL and Caspase-8 protein expression, and down-regulating of Bcl-2 protein expression. These results indicated that baicalin-induced apoptosis involved activation Caspase-3 in HeLa cells through the intracellular mitochondrial pathway and the surface death receptor pathway.
PMCID: PMC4277638  PMID: 25561931
Baicalin; HeLa cells; Cell apoptosis; Mitochondrial pathway; Death receptor pathway; Caspase-3
18.  Reservoir Host Expansion of Hantavirus, China 
Emerging Infectious Diseases  2015;21(1):170-171.
PMCID: PMC4285249  PMID: 25531113
Hantavirus; seroprevalence; shrew; rodent; China; viruses
19.  Gadd45b is a Novel Mediator of Neuronal Apoptosis in Ischemic Stroke 
Apoptosis plays an essential role in ischemic stroke pathogenesis. Research on the process of neuronal apoptosis in models of ischemic brain injury seems promising. The role of growth arrest and DNA-damage-inducible protein 45 beta (Gadd45b) in brain ischemia has not been fully examined to date. This study aims to investigate the function of Gadd45b in ischemia-induced apoptosis. Adult male Sprague-Dawley rats were subjected to brain ischemia by middle cerebral artery occlusion (MCAO). RNA interference (RNAi) system, which is mediated by a lentiviral vector (LV), was stereotaxically injected into the ipsilateral lateral ventricle to knockdown Gadd45b expression. Neurologic scores and infarct volumes were assessed 24 h after reperfusion. Apoptosis-related molecules were studied using immunohistochemistry and Western blot analysis. We found that Gadd45b-RNAi significantly increased infarct volumes and worsened the outcome of transient focal cerebral ischemia. Gadd45b-RNAi also significantly increased neuronal apoptosis as indicated by increased levels of Bax and active caspase-3, and decreased levels of Bcl-2. These results indicate that Gadd45b is a beneficial mediator of neuronal apoptosis.
PMCID: PMC4323375
MCAO; Gadd45b; BDNF; Apoptosis
20.  Specific Phosphorylation of Histone Demethylase KDM3A Determines Target Gene Expression in Response to Heat Shock 
PLoS Biology  2014;12(12):e1002026.
Phosphorylation of histone demethylase KDM3A in response to thermal stress enables its specific recruitment to target genes by Stat1.
Histone lysine (K) residues, which are modified by methyl- and acetyl-transferases, diversely regulate RNA synthesis. Unlike the ubiquitously activating effect of histone K acetylation, the effects of histone K methylation vary with the number of methyl groups added and with the position of these groups in the histone tails. Histone K demethylases (KDMs) counteract the activity of methyl-transferases and remove methyl group(s) from specific K residues in histones. KDM3A (also known as JHDM2A or JMJD1A) is an H3K9me2/1 demethylase. KDM3A performs diverse functions via the regulation of its associated genes, which are involved in spermatogenesis, metabolism, and cell differentiation. However, the mechanism by which the activity of KDM3A is regulated is largely unknown. Here, we demonstrated that mitogen- and stress-activated protein kinase 1 (MSK1) specifically phosphorylates KDM3A at Ser264 (p-KDM3A), which is enriched in the regulatory regions of gene loci in the human genome. p-KDM3A directly interacts with and is recruited by the transcription factor Stat1 to activate p-KDM3A target genes under heat shock conditions. The demethylation of H3K9me2 at the Stat1 binding site specifically depends on the co-expression of p-KDM3A in the heat-shocked cells. In contrast to heat shock, IFN-γ treatment does not phosphorylate KDM3A via MSK1, thereby abrogating its downstream effects. To our knowledge, this is the first evidence that a KDM can be modified via phosphorylation to determine its specific binding to target genes in response to thermal stress.
Author Summary
Histone methylation regulates gene expression and can have drastic consequences for health if the process is defective. Histone lysine demethylases (KDMs) counteract the activity of methyl-transferases and remove methyl group(s) from histones. KDM3A is a H3K9me2/1 demethylase that performs diverse functions via the regulation of its target genes, which are involved in spermatogenesis, metabolism, and cell differentiation. However, the mechanisms underlying KDM3A regulation of specific genes at specific times are largely unknown. Here we found that a physiological stress—elevated temperature—induces KDM3A phosphorylation in human cells via the MSK1 kinase. This phosphorylated form of KDM3A directly interacts with the transcription factor Stat1, which enables Stat1 to recruit KDM3A to Stat1-binding sequences at the promoters of specific target genes. KDM3A then acts to demethylate H3K9me2/1 at these targets, thereby causing specific gene expression in response to the thermal stress. We conclude that heat shock can affect the expression of many genes in human cells via a novel activation mechanism that is centered around the phosphorylation of KDM3A.
PMCID: PMC4275180  PMID: 25535969
21.  Meta-analysis of the efficacy of probiotics in Helicobacter pylori eradication therapy 
World Journal of Gastroenterology : WJG  2014;20(47):18013-18021.
AIM: To evaluate the role of probiotics in the standard triple Helicobacter pylori therapy.
METHODS: In this meta-analysis, we investigated the efficacy of probiotics in a standard triple H. pylori therapy in adults. Searches were mainly conducted in MEDLINE/PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. Fourteen studies met our criteria, and the quality of these studies was assessed using the Jadad scale. We used STATA version 12.0 to extract data and to calculate the odds ratios (ORs), which are presented with the corresponding 95% confidence intervals (CIs). The data are presented as forest plots.
RESULTS: The pooled ORs for the eradication rates calculated by intention-to-treat analysis and per-protocol analysis in the probiotic group vs the control group were 1.67 (95%CI: 1.38-2.02) and 1.68 (95%CI: 1.35-2.08), respectively, using the fixed-effects model. The sensitivity of the Asian studies was greater than that of the Caucasian studies (Asian: OR = 1.78, 95%CI: 1.40-2.26; Caucasian: OR = 1.48, 95%CI: 1.06-2.05). The pooled OR for the incidence of total adverse effects was significantly lower in the probiotic group (OR = 0.49, 95%CI: 0.26-0.94), using the random effects model, with significant heterogeneity (I2 = 85.7%). The incidence of diarrhea was significantly reduced in the probiotic group (OR = 0.21, 95%CI: 0.06-0.74), whereas the incidence of taste disorders, metallic taste, vomiting, nausea, and epigastric pain did not differ significantly between the probiotic group and the control group.
CONCLUSION: Supplementary probiotic preparations during standard triple H. pylori therapy may improve the eradication rate, particularly in Asian patients, and the incidence of total adverse effects.
PMCID: PMC4273153  PMID: 25548501
Helicobacter pylori; Eradication; Probiotics; Meta-analysis; Adult
22.  Primary carcinoid tumor of medulla spinalis: case report and review of the literature 
Carcinoid tumors are slow growing neuroendocrine tumors which can originate from various sites within the body. A carcinoid tumor originating in the medulla spinalis has not previously been reported in the literature.
Case report
We report a case of a 33-year-old man, presenting with a five-month history of bilateral lower extremity pain, as well as paresthesia, and mild weakness in one lateral lower extremity. A lumbar laminectomy of L3 to L5 and en bloc resection of the tumor was performed. Postoperative histopathology and immunohistochemical analysis of the tumor were consistent with that of a carcinoid tumor. There were no clinical or radiological signs of tumor recurrence or metastasis at the patient’s two year postoperative follow-up.
During the differential diagnosis of medulla spinalis tumors, the possibility of a primary carcinoid tumor originating within the medulla spinalis should be considered. An accurate tumor classification is imperative to ensure that the most effective course of treatment is pursued.
Electronic supplementary material
The online version of this article (doi:10.1186/s40001-014-0071-7) contains supplementary material, which is available to authorized users.
PMCID: PMC4272791  PMID: 25523133
Carcinoid tumor; Medulla spinalis; Neuroendocrine tumor; Spinal tumor
23.  Elevated expression levels of androgen receptors and matrix metalloproteinase-2 and -9 in 30 cases of hepatocellular carcinoma compared with adjacent tissues as predictors of cancer invasion and staging 
The aim of the present study was to investigate the potential roles of the androgen receptor (AR) and matrix metalloproteinase (MMP)-2 and MMP-9 in hepatocellular carcinoma (HCC) tissues and whether their expression could be used as a predictor of the invasion and stage of cancer. The expression levels of AR, MMP-2 and MMP-9 in HCC tissues and tissues adjacent to the tumor were measured by immunohistochemical staining assay. The expression rates of AR, MMP-2 and MMP-9 in the HCC tissue were 76.67, 73.33 and 76.67%, respectively, all of which were significantly higher than those in the tissues adjacent to the tumor. The expression of these proteins represents the local invasion and stage. AR, MMP-2 and MMP-9 expression levels in HCC tissues have the potential to be employed as predictors of the progression of local cancer invasion and the tumor stage.
PMCID: PMC4316905  PMID: 25667651
hepatocellular carcinoma; androgen receptor; matrix metalloproteinase-2; matrix metalloproteinase-9
24.  Current level and determinants of inappropriate admissions to township hospitals under the new rural cooperative medical system in China: a cross-sectional study 
The increased funding and reimbursement for the New Rural Cooperative Medical System (NRCMS) have provided residents in rural China with better access to inpatient services. This research aims to examine the level of inappropriate admissions to township hospitals under NRCMS, and the determinants that influence inappropriate admissions.
A total of 2,044 medical records in 10 township hospitals were collected from five counties in Midwestern China by stratified cluster sampling and evaluated using the Appropriateness Evaluation Protocol (AEP), which was developed by a Delphi expert consultation of 32 experts. A two-level logistic regression model by MLwiN 2.30 was used to examine the determinants of inappropriate admissions.
Township hospitals had an average inappropriate admission rate of 26.5%. The highest rate of inappropriate admission was among patients aged more than 59 years old (30.1%). Inappropriate admissions mostly occurred for respiratory and circulatory diseases. Township hospital similarity and clustering were observed. Two-level logistic regression analysis showed that age, treating department, and disease were determinants of inappropriate admission.
Township hospitals have a high rate of inappropriate admissions. Explicit diagnostic criteria and a standardized supervision system should be developed to reduce this.
PMCID: PMC4310202  PMID: 25519885
Appropriateness evaluation protocol; Inappropriate admission; New Rural Cooperative Medical System; Rural China; Township hospital
25.  Proprotein convertase subtilisin/kexin type 9 expression is transiently up-regulated in the acute period of myocardial infarction in rat 
The proprotein convertase subtilisin/kexin type 9 (PCSK9) has been confirmed as a major factor regulating cholesterol homeostasis and has low-density lipoprotein receptor (LDLR) independent effects. In addition, the pathogenesis of acute myocardial infarction (AMI) involves lipids alteration and other acute phase responses. It remains unknown whether the PCSK9 expression is influenced by the impact of AMI. The present study aimed to investigate the changes of PCSK9 concentration using AMI rat model.
AMI (n = 6-8 at each time point) or sham operated (n = 6) adult male rats model were used. Whole blood and liver tissue were collected at 1, 3, 6, 9, 12, 24, 48, and 96 hour (h) post infarction. The plasma PCSK9 concentration was measured by ELISA and lipid profiles were measured by enzymatic assay. The liver mRNA levels of PCSK9, LDLR, sterol response element binding protein-2 (SREBP-2) and hepatocyte nuclear factor 1α (HNF1α) were measured by quantitative real-time PCR.
The plasma PCSK9 concentration was increased from 12 h to 96 h (P < 0.05 vs. control). Paralleled with the enhanced plasma PCSK9 concentration, the hepatic PCSK9 mRNA expression was up-regulated by 2.2-fold at 12 h and 4.1-fold at 24 h. Hepatic mRNA levels of LDLR, SREBP-2 and HNF1α were all increased and lipid profiles underwent great changes at this acute period.
We firstly demonstrated that PCSK9 was transiently up-regulated in the acute period of AMI, which is also driven by transcriptional factors, SREBP-2 and HNF1α, suggesting that the role of PCSK9 in myocardial injury may be needed further study.
PMCID: PMC4279995  PMID: 25519174
Acute myocardial infarction; PCSK9; Rat

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