Search tips
Search criteria

Results 1-25 (41)

Clipboard (0)

Select a Filter Below

Year of Publication
1.  Prevalence of Cognitive Impairment No Dementia in a Rural Area of Northern China 
Neuroepidemiology  2014;42(4):197-203.
Few data are available on the prevalence of cognitive impairment no dementia (CIND) in rural China. The aim of this study was to estimate the prevalence of CIND in individuals aged 60 years and older in a large rural community, and to analyze the associated risk factors.
A two-phase, door-to-door epidemiological study was used for residents aged 60 years and older in Ji County, a rural county near Tianjin in Northern China. In phase 1 of the study, the Mini-Mental State Examination and Clinical Dementia Rating were administered for screening purposes. In phase 2, the subjects who screened positive were further examined by neurologists. A total of 5,744 individuals underwent the home visit interview, where demographic variables and comorbidities were recorded; 5,550 individuals completed the two phases. CIND was diagnosed by the Aging, Demographics and Memory Study on CIND criteria. The odds ratio (OR) for each risk factor was calculated by logistic regression analysis.
The prevalence of CIND among those aged 60 years and older was 23.3%. The prevalence of CIND was lower among those with a higher level of education or social involvement. CIND was more prevalent in fe males, older individuals, those with a past history of stroke, and those living without a partner. Significant risk factors were found by multivariate analyses: past history of stroke (OR = 1.889; 95% CI: 1.437–2.483); being female (OR = 1.546; 95% CI: 1.305–1.832); and having no partner (divorced, widowed or single; OR = 1.250; 95% CI: 1.042–1.499). In turn, level of education (OR = 0.560; 95% CI: 0.460–0.681) and engagement in social activities (OR = 0.339; 95% CI: 0.258–0.404) were protective factors.
This is the first large-scale community-based epidemiological study assessing the prevalence of cognitive loss in the rural Chinese population. The total prevalence of CIND observed was 23.3%, which was higher than in other studies in Western and Asian countries. Living without a partner, female gender and previous stroke increased the risk of CIND, whereas a higher level of education and engagement in social activities reduced the risk of CIND.
PMCID: PMC4074439  PMID: 24751796
Cognitive impairment no dementia; China; Prevalence
2.  tRNA synthetase counteracts c-Myc to develop functional vasculature 
eLife  2014;3:e02349.
Recent studies suggested an essential role for seryl-tRNA synthetase (SerRS) in vascular development. This role is specific to SerRS among all tRNA synthetases and is independent of its well-known aminoacylation function in protein synthesis. A unique nucleus-directing domain, added at the invertebrate-to-vertebrate transition, confers this novel non-translational activity of SerRS. Previous studies showed that SerRS, in some unknown way, controls VEGFA expression to prevent vascular over-expansion. Using in vitro, cell and animal experiments, we show here that SerRS intervenes by antagonizing c-Myc, the major transcription factor promoting VEGFA expression, through a tandem mechanism. First, by direct head-to-head competition, nuclear-localized SerRS blocks c-Myc from binding to the VEGFA promoter. Second, DNA-bound SerRS recruits the SIRT2 histone deacetylase to erase prior c-Myc-promoted histone acetylation. Thus, vertebrate SerRS and c-Myc is a pair of ‘Yin-Yang’ transcriptional regulator for proper development of a functional vasculature. Our results also discover an anti-angiogenic activity for SIRT2.
eLife digest
The network of blood vessels is one of the earliest structures to develop in a vertebrate embryo. A protein called Vascular Endothelial Growth Factor A (or VEGFA for short) is needed to promote the growth of these blood vessels, but too much VEGFA can cause blood vessels to grow too much and to grow abnormally.
Like most of the DNA in the nucleus, the gene for VEGFA is tightly wrapped around proteins called histones and must be unwrapped before it can be expressed as a protein. For the VEGFA gene, this unwrapping process starts when a protein called c-Myc adds chemical tags to the histones.
Recent research suggested that an enzyme called seryl-tRNA synthetase (or SerRS for short) also controls the expression of VEGFA. This came as a surprise because no other tRNA synthetase has a similar role during development. And although SerRS is known to enter the cell nucleus in vertebrates, researchers did not know what SerRS did in the nucleus to control the expression of VEGFA.
Now, Shi et al. have discovered that SerRS controls blood vessel development in zebrafish embryos by counteracting the activity of c-Myc. It does this in two different ways: first, it directly blocks c-Myc from binding to and unpacking the DNA; and second, SerRS works with another enzyme to remove tags that are already on the histones. Shi et al. found that if the expression of this other enzyme (called SIRT2) was reduced in zebrafish, the fish expressed more VEGFA and their blood vessels grew too much.
Since blood vessel growth is important in the development of cancers, the findings of Shi et al. could also lead to a better understanding of how tumors develop, as well as how blood vessels develop normally.
PMCID: PMC4057782  PMID: 24940000
seryl-tRNA synthetase; c-Myc; VEGFA; SIRT2; angiogenesis; vasculature; human; zebrafish
3.  IMP3 expression is associated with epithelial-mesenchymal transition in breast cancer 
IMP3 plays an important role in tumor invasion and metastasis, to which epithelial to mesenchymal transition (EMT) also contributes. The purpose of this study was to investigate whether IMP3 can regulate invasion and metastasis through EMT in breast cancers. The protein expression levels of IMP3 and EMT markers were analyzed by immunohistochemistry in 180 paraffin-embedded human breast tissue samples. There was an inverse correlation of IMP3 with E-cadherin protein expression (P = 0.042). IMP3 expression directly correlated with both Slug (P = 0.004) and vimentin (P < 0.001). Changes in E-cadherin, vimentin, and Slug mRNA and protein levels were examined by quantitative real-time reverse polymerase chain reaction (qRT-PCR) and western blotting. Overexpression of IMP3 reduced the expression of E-cadherin and upregulated Slug and vimentin in transfected cells. In contrast, knocking down IMP3 had the opposite expression of the three proteins. Ribo-immunoprecipitation qPCR revealed that IMP3 binds Slug mRNA directly. In a transwell assay, overexpression of Slug rescued the cell migration and invasion caused by silencing IMP3 in MDA-MB-231 cells. On the other hand, knockdown of Slug in T47D-IMP3 cells could also have the opposite change. Our results strengthen the association of IMP3 with the regulation of EMT. Slug is a functional target of IMP3. IMP3 could therefore promote invasion and migration through the EMT in breast cancer cells.
PMCID: PMC4097240  PMID: 25031719
Insulin-like growth factor II (IGF-II) mRNA binding protein 3 (IMP3); epithelial-mesenchymal transition; ribo-immunoprecipitation; metastasis; breast cancer
4.  Architecture and Metamorphosis 
Topics in current chemistry  2014;344:89-118.
When compared to other conserved housekeeping protein families, such as ribosomal proteins, during the evolution of higher eukaryotes, aminoacyl-tRNA synthetases (aaRSs) show an apparent high propensity to add new sequences, and especially, new domains. The stepwise emergence of those new domains is consistent with their involvement in a broad range of biological functions beyond protein synthesis, and correlates with the increasing biological complexity of higher organisms. The new domains have been extensively characterized based on their evolutionary origins and their sequence, structural and functional features. While some of the domains are uniquely found in aaRSs and may have originated from nucleic acid binding motifs, others are common domain modules mediating protein-protein interactions that play a critical role in the assembly of the multi-synthetase complex (MSC). Interestingly, the MSC has emerged from a miniature complex in yeast, to a large, stable complex in insects to humans. The human MSC consists of 9 aaRSs (LysRS, ArgRS, GlnRS, AspRS, MetRS, IleRS, LeuRS and GluProRS) and 3 scaffold proteins (AIMP1/p43, AIMP2/p38 and AIMP3/p18), and has a molecular weight of 1.5 million Da. The MSC has been proposed to have a functional dualism: both facilitating protein synthesis and serving as a reservoir of non-canonical functions associated with its synthetase and non-synthetase components. Importantly, domain additions and functional expansions are not limited to the components of the MSC and are found in almost all aaRS proteins. From a structural perspective, multi-functionalities are represented by multiple conformational states. In fact, alternative conformations of aaRSs have been generated by various mechanisms from proteolysis to alternative splicing and posttranslational modifications, as well as by disease-causing mutations. Therefore, the metamorphosis between different conformational states is connected to the activation and regulation of the novel functions of aaRSs in higher eukaryotes.
PMCID: PMC3864538  PMID: 23536245
Domain expansion; Evolution; Novel function; Structural metamorphosis; tRNA synthetase
5.  Protective Effect of Glycyrrhizin, a Direct HMGB1 Inhibitor, on Focal Cerebral Ischemia/Reperfusion-Induced Inflammation, Oxidative Stress, and Apoptosis in Rats 
PLoS ONE  2014;9(3):e89450.
Glycyrrhizin (GL) has been reported to protect against ischemia and reperfusion (I/R)-induced injury by inhibiting the cytokine activity of high mobility group box 1 (HMGB1). In the present study, the protective effects of GL against I/R injury, as well as the related molecular mechanisms, were investigated in rat brains.
Focal cerebral I/R injury was induced by intraluminal filamentous occlusion of the middle cerebral artery (MCA) in Male Sprague-Dawley rats. GL alone or GL and rHMGB1 were administered intravenously at the time of reperfusion. Serum levels of HMGB1 and inflammatory mediators were quantified via enzyme-linked immunosorbent assay (ELISA). Histopathological examination, immunofluorescence, RT-PCR and western blotting analyses were performed to investigate the protective and anti-apoptotic effects and related molecular mechanisms of GL against I/R injury in rat brains.
Pre-treatment with GL significantly reduced infarct volume and improved the accompanying neurological deficits in locomotor function. The release of HMGB1 from the cerebral cortex into the serum was inhibited by GL administration. Moreover, pre-treatment with GL alleviated apoptotic injury resulting from cerebral I/R through the inhibition of cytochrome C release and caspase 3 activity. The expression levels of inflammation- and oxidative stress-related molecules including TNF-α, iNOS, IL-1β, and IL-6, which were over-expressed in I/R, were decreased by GL. P38 and P-JNK signalling were involved in this process. All of the protective effects of GL could be reversed by rHMGB1 administration.
GL has a protective effect on ischemia-reperfusion injury in rat brains through the inhibition of inflammation, oxidative stress and apoptotic injury by antagonising the cytokine activity of HMGB1.
PMCID: PMC3942385  PMID: 24594628
6.  Reexpression of Let-7g MicroRNA Inhibits the Proliferation and Migration via K-Ras/HMGA2/Snail Axis in Hepatocellular Carcinoma 
BioMed Research International  2014;2014:742417.
Let-7 family microRNAs have been reported to be downregulated in human hepatocellular carcinoma in comparison with normal hepatic tissues. Among them, let-7g was identified as the lowest expression using real-time RT-PCR. However, the mechanism by which let-7g works in hepatocellular carcinoma remains unknown. Here, in our present study, we have had let-7g reexpressed in vitro in hepatocellular carcinoma cell lines MHCC97-H and HCCLM3 via transfection. The proliferation after reexpression of let-7g was assayed using MTT method; the migration and invasion after restoration were detected by wound-healing and Transwell assay, respectively. We found using Western-blotting that let-7g can regulate epithelial-mesenchymal transition (EMT) by downregulating K-Ras and HMGA2A after reexpresssion. Xenografted nude mice were used to observe whether or not reexpression of let-7g could have potential therapeutic ability. In vivo, to observe the association with let-7g expression and overall prognosis, 40 paired cases of hepatocellular carcinoma were analyzed using in situ hybridization (ISH). It was found that reexpression of let-7g can inhibit the proliferation, migration, and invasion significantly, and that low expression of let-7g was significantly associated with poorer overall survival. Taken together, let-7g could be used as a promising therapeutic agent in vivo in the treatment of hepatocellular carcinoma at the earlier stage.
PMCID: PMC3960551  PMID: 24724096
7.  Neutrophils Infiltration in the Tongue Squamous Cell Carcinoma and Its Correlation with CEACAM1 Expression on Tumor Cells 
PLoS ONE  2014;9(2):e89991.
The present study aimed to explore the clinical significance of neutrophils infiltration and carcinoembryonic antigen related cell adhesion molecule 1 (CEACAM1) expression in the tongue squamous cell carcinoma (TSCC), and to probe the possible relationship between them.
Materials and Methods
Tissue microarray and immunohistochemistry were used to detect neutrophils density and CEACAM1 expression in 74 cases of primary TSCC specimens and 17 cases of corresponding peritumoral tissues. The relationship of CEACAM1 expression and neutrophils density with clinicopathologic parameters and cancer-related survival of TSCC patients were evaluated. The correlation between CEACAM1 expression and neutrophils density was also evaluated. Real-time quantitative transcription polymerase chain reaction (qRT-PCR) was used to explore the possible molecular mechanisms between CEACAM1 expression and neutrophils infiltration.
Immunohistochemistry evaluation revealed that there was more neutrophils infiltration in TSCC tissues than in peritumoral tissues. High neutrophil density was associated with LN metastasis (P = 0.01), higher clinical stage (P = 0.037) and tumor recurrence (P = 0.024). CEACAM1 overexpression was also associated with lymph node metastasis (P = 0.000) and higher clinical stage (P = 0.001). Survival analysis revealed that both neutrophils infiltration and CEACAM1 overexpression were associated with poorer cancer-related survival of TSCC patients (P<0.05), and neutrophils infiltration was an independent prognostic factor for TSCC (P<0.05). Furthermore, overexpression of CEACAM1 was correlated with more neutrophils infiltration in TSCC tissues (P<0.01). qRT-PCR results showed that CEACAM1-4L can upregulate the mRNA expression of IL-8 and CXCL-6, which were strong chemotactic factors of neutrophils.
Our results demonstrated that more neutrophils infiltration and overexpression of CEACAM1 were associated with poor clinical outcomes in TSCC tissues. Overexpression of CEACAM1 on tumor cells correlated with more neutrophils infiltration to some extent through upregulating mRNA expression of IL-8 and CXCL-6.
PMCID: PMC3937421  PMID: 24587171
8.  Suggestion of GLYAT gene underlying variation of bone size and body lean mass as revealed by a bivariate genome-wide association study 
Human genetics  2012;132(2):189-199.
Bone and muscle, two major tissue types of musculoskeletal system, have strong genetic determination. Abnormality in bone and/or muscle may cause musculoskeletal diseases such as osteoporosis and sarcopenia. Bone size phenotypes (BSPs), such as hip bone size (HBS), appendicular bone size (ABS), are genetically correlated with body lean mass (mainly muscle mass). However, the specific genes shared by these phenotypes are largely unknown. In this study, we aimed to identify the specific genes with pleiotropic effects on BSPs and appendicular lean mass (ALM).
We performed a bivariate genome-wide association study (GWAS) by analyzing ~690,000 SNPs in 1,627 unrelated Han Chinese adults (802 males and 825 females) followed by a replication study in 2,286 unrelated US Caucasians (558 males and 1728 females).
We identified 14 interesting single nucleotide polymorphisms (SNPs) that may contribute to variation of both BSPs and ALM, with p values <10−6 in discovery stage. Among them, the association of three SNPs (rs2507838, rs7116722, and rs11826261) in/near GLYAT (glycine-N-acyltransferase) gene was replicated in US Caucasians, with p values ranging from 1.89×10−3 to 3.71×10−4 for ALM-ABS, from 5.14×10−3 to 1.11×10−2 for ALM-HBS, respectively. Meta-analyses yielded stronger association signals for rs2507838, rs7116722, and rs11826261, with pooled p values of 1.68×10−8, 7.94×10−8, 6.80×10−8 for ALB-ABS and 1.22×10−4, 9.85×10−5, 3.96×10−4 for ALM-HBS, respectively. Haplotype allele ATA based on these three SNPs were also associated with ALM-HBS and ALM-ABS in both discovery and replication samples. Interestingly, GLYAT was previously found to be essential to glucose metabolism and energy metabolism, suggesting the gene’s dual role in both bone development and muscle growth.
Our findings, together with the prior biological evidence, suggest the importance of GLYAT gene in co-regulation of bone phenotypes and body lean mass.
PMCID: PMC3682481  PMID: 23108985
Bivariate GWAS; Bone size; Lean mass; GLYAT
9.  Influence of Preferred Orientation on the Electrical Conductivity of Fluorine-Doped Tin Oxide Films 
Scientific Reports  2014;4:3679.
Current development of high-performance transparent conductive oxide (TCO) films is limited with tradeoff between carrier mobility and concentration since none of them can be improved without sacrificing the other. In this study, we prepare fluorine doped tin oxide (FTO) films by chemical vapor deposition with inclusions of different additives and report that the mobility can be varied from 0.65 to 28.5 cm2 V−1 s−1 without reducing the achieved high carrier concentration of 4 × 1020 cm−3. Such an increase in mobility is shown to be clearly associated with the development of (200) preferred orientation (PO) but concurrent degradation of (110) PO in films. Thus, at a constant high carrier concentration, the electrical conductivity can be improved via carrier mobility simply by PO control. Such a one-step approach avoiding conventional post-deposition treatment is suggested for developing next-generation FTO as well as other TCO films with better than ever conductivities.
PMCID: PMC3890905  PMID: 24419455
10.  Structural Switch of Lysyl-tRNA Synthetase Between Translation and Transcription 
Molecular cell  2012;49(1):30-42.
Lysyl-tRNA synthetase (LysRS), a component of the translation apparatus, is released from the cytoplasmic multi-tRNA synthetase complex (MSC) to activate the transcription factor MITF in stimulated mast cells through undefined mechanisms. Here we show that Ser207-phosphorylation provokes a new conformer of LysRS that inactivates its translational, but activates its transcriptional function. The crystal structure of an MSC sub-complex established that LysRS is held in the MSC by binding to the N-terminus of the scaffold protein p38/AIMP2. Phosphorylation-created steric clashes at the LysRS domain interface disrupt its binding grooves for p38/AIMP2, releasing LysRS and provoking its nuclear translocation. This alteration also exposes the C-terminal domain of LysRS to bind to MITF and triggers LysRS-directed production of the second messenger Ap4A that activates MITF. Thus our results establish that a single conformational change triggered by phosphorylation leads to multiple effects driving an exclusive switch of LysRS function from translation to transcription.
PMCID: PMC3766370  PMID: 23159739
tRNA synthetase; Structure; Phosphorylation; H/D Exchange; Hydrogen/Deuterium Exchange; Mass Spectrometry; Fourier Transform; Ion Cyclotron Resonance; FTMS; Conformational Change
11.  Trp-tRNA synthetase bridges DNA-PKcs to PARP-1 to link IFN-γ and p53 Signaling 
Nature chemical biology  2012;8(6):547-554.
IFN-γ engenders strong anti-proliferative responses, in part through activation of p53. However, the long-known IFN-γ-dependent upregulation of human Trp-tRNA synthetase (TrpRS), a cytoplasmic enzyme that activates tryptophan to form Trp-AMP in the first step of protein synthesis, is unexplained. Here we report a nuclear complex of TrpRS with the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs) and with poly (ADP-ribose) polymerase 1 (PARP-1), the major PARP in human cells. The IFN-γ-dependent poly (ADP-ribosyl)ation of DNA-PKcs (which activates its kinase function) and concomitant activation of p53 were specifically prevented by Trp-SA, an analog of Trp-AMP that disrupted the TrpRS/DNA-PKcs/PARP-1 complex. The connection of TrpRS to p53 signaling in vivo was confirmed in a vertebrate system. These and further results suggest a surprising evolutionary expansion of the protein synthesis apparatus to a nuclear role that links major signaling pathways.
PMCID: PMC3780985  PMID: 22504299
12.  Internally deleted human tRNA synthetase suggests evolutionary pressure for repurposing 
Structure (London, England : 1993)  2012;20(9):1470-1477.
Aminoacyl-tRNA synthetases (AARSs) catalyze aminoacylation of tRNAs in the cytoplasm. Surprisingly, AARSs also have critical extracellular and nuclear functions. Evolutionary pressure for new functions might be manifested by splice variants that skip only an internal catalytic domain (CD) and link non-catalytic N- and C-terminal polypeptides. Using disease-associated histidyl-tRNA synthetase (HisRS) as an example, we discovered an expressed 171 amino acid protein (HisRSΔCD) that deleted the entire CD, and joined an N-terminal WHEP to the C-terminal anticodon-binding domain (ABD). X-ray crystallographic and 3-D NMR methods revealed the first structures of human HisRS and HisRSΔCD. In contrast to homodimeric HisRS, HisRSΔCD is monomeric, where rupture of the ABD’s packing with CD resulted in a dumbbell-like structure of flexibly linked WHEP and ABD domains. In addition, the ABD of HisRSΔCD presents a new local conformation. This natural internally deleted HisRS suggests evolutionary pressure to reshape AARS tertiary and quaternary structures for repurposing.
PMCID: PMC3485694  PMID: 22958643
13.  ATP-Directed Capture of Bioactive Herbal-Based Medicine on Human tRNA Synthetase 
Nature  2012;494(7435):121-124.
PMCID: PMC3569068  PMID: 23263184
14.  Intranasal immunization with a helper-dependent adenoviral vector expressing the codon-optimized fusion glycoprotein of human respiratory syncytial virus elicits protective immunity in BALB/c mice 
Virology Journal  2013;10:183.
Human respiratory syncytial virus (RSV) is a serious pediatric pathogen of the lower respiratory tract. Currently, there is no clinically approved vaccine against RSV infection. Recent studies have shown that helper-dependent adenoviral (HDAd) vectors may represent effective and safe vaccine vectors. However, viral challenge has not been investigated following mucosal vaccination with HDAd vector vaccines.
To explore the role played by HDAd as an intranasally administered RSV vaccine vector, we constructed a HDAd vector encoding the codon optimized fusion glycoprotein (Fsyn) of RSV, designated HDAd-Fsyn, and delivered intranasally HDAd-Fsyn to mice.
RSV-specific humoral and cellular immune responses were generated in BALB/c mice, and serum IgG with neutralizing activity was significantly elevated after a homologous boost with intranasal (i.n.) application of HDAd-Fsyn. Humoral immune responses could be measured even 14 weeks after a single immunization. Immunization with i.n. HDAd-Fsyn led to effective protection against RSV infection on challenge.
The results indicate that HDAd-Fsyn can induce powerful systemic immunity against subsequent i.n. RSV challenge in a mouse model and is a promising candidate vaccine against RSV infection.
PMCID: PMC3685604  PMID: 23742026
Human respiratory syncytial virus; Helper-dependent adenovirus vectors; Fusion glycoprotein; Protective immunity; Immune responses
15.  The effect-enhancing and toxicity-reducing activity of Hypericum japonicum Thunb. extract in murine liver cancer chemotherapy 
Molecular and Clinical Oncology  2012;1(2):395-399.
Chinese herbs are potential sources of antitumor drugs with immunoregulatory activity and few adverse effects. In the present study, we investigated whether the Hypericum japonicum Thunb. (HJT) extract enhanced the efficacy of 5-fluorouracil (5-FU) treatment in murine liver tumor xenografts and reduced toxicity of chemotherapy in hepatoma H22-bearing mice. Tumor weight and inhibition rate, thymus and spleen indices, as well as white blood cell (WBC) count were calculated. The phagocytic function of macrophages was assessed by observing peritoneal macrophages phagocytized chicken red blood cells (RBC). Body weight and toxic reactions of the chemotherapeutic and life prolongation rate were investigated in the mice. Results demonstrated that the HJT extract significantly enhanced the tumor inhibition rate of 5-FU, improved the immune function, reduced the toxic effects and prolonged the survival time in the tumor-bearing mice. Taken together, these results indicated that the HJT extract has a synergistic tumor-inhibiting effect with 5-FU, is able to reduce the toxic side effects and is likely to be safe and efficacious for use in antitumor therapy.
PMCID: PMC3956279  PMID: 24649182
antitumor; Hypericum japonicum Thunb.; hepatoma; chemotherapy; mice
16.  Efficient multicistronic co-expression of hNIS and hTPO in prostate cancer cells for nonthyroidal tumor radioiodine therapy 
Radioiodine therapy has proven to be a safe and effective approach in the treatment of differentiated thyroid cancer. Similar treatment strategies have been exploited in nonthyroidal malignancies by transfecting hNIS gene into tumor cells or xenografts. However, rapid radioiodine efflux is often observed after radioiodine uptake, limiting the overall antitumor effects. In this study, we aimed at constructing multicistronic co-expression of hNIS and hTPO genes in tumor cells to enhance the radioiodine uptake and prolong the radioiodine retention. Driven by the cytomegalovirus promoter, hNIS and hTPO were simultaneously inserted into the expression cassette of adenoviral vector. An Ad5 viral vector (Ad-CMV-hTPO-T2A-hNIS) was assembled as a gene therapy vehicle by Gateway technology and 2A method. The co-expression of hNIS and hTPO genes was confirmed by a double-label immunofluorescence assay. The radioiodine (125I) uptake and efflux effects induced by co-expression of hNIS and hTPO genes were determined in transfected and non-transfected PC-3 cells. Significantly higher uptake (6.58 ± 0.56 fold, at 1 h post-incubation) and prolonged retention (5.47 ± 0.36 fold, at 1 h of cell efflux) of radioiodine (125I) were observed in hNIS and hTPO co-expressed PC-3 cells as compared to non-transfected PC-3 cells. We concluded that the new virus vector displayed favorable radioiodine uptake and retention properties in hNIS-hTPO transfected PC-3 cells. Our study will provide valuable information on improving the efficacy of hNIS-hTPO co-mediated radioiodine gene therapy.
PMCID: PMC3484425  PMID: 23145364
Gene therapy; prostate cance; hNIS; hTPO; gateway cloning system
17.  Inhalation of hydrogen gas reduces liver injury during major hepatotectomy in swine 
AIM: To study the effect of H2 gas on liver injury in massive hepatectomy using the Intermittent Pringle maneuver in swine.
METHODS: Male Bama pigs (n = 14) treated with ketamine hydrochloride and Sumianxin II as induction drugs followed by inhalation anesthesia with 2% isoflurane, underwent 70% hepatotectomy with loss of bleeding less than 50 mL, and with hepatic pedicle occlusion for 20 min, were divided into two groups: Hydrogen-group (n = 7), the pigs with inhalation of 2% hydrogen by the tracheal intubation during major hepatotectomy; Contrast-group (n = 7), underwent 70% hepatotectomy without inhalation of hydrogen. Hemodynamic changes and plasma concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), hyaluronic acid (HA), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and malondialdehyde (MDA) in liver tissue were measured at pre-operation, post-hepatotectomy (PH) 1 h and 3 h. The apoptosis and proliferating cell nuclear antigen (PCNA) expression in liver remnant were evaluated at PH 3 h. Then we compared the two groups by these marks to evaluate the effect of the hydrogen in the liver injury during major hepatotectomy with the Pringle Maneuver in the swine.
RESULTS: There were no significant differences in body weight, blood loss and removal liver weight between the two groups. There was no significant difference in changes of portal vein pressure between two groups at pre-operation, PH 30 min, but in hydrogen gas treated-group it slightly decrease and lower than its in Contrast-group at PH 3 h, although there were no significant difference (P = 0.655). ALT and AST in Hydrogen-group was significantly lower comparing to Contrast-group (P = 0.036, P = 0.011, vs P = 0.032, P = 0.013) at PH 1 h and 3 h, although the two groups all increased. The MDA level increased between the two group at PH 1 h and 3 h. In the hydrogen gas treated-group, the MDA level was not significantly significant at pre-operation and significantly low at PH 1 h and 3 h comparing to Contrast-group (P = 0.0005, P = 0.0004). In Hydrogen-group, the HA level was also significantly low to Contrast-group (P = 0.0005, P = 0.0005) although the two groups all increased at PH 1 h and 3 h. The expression of cluster of differentiation molecule 31 molecules Hydrogen-group was low to Contrast-group. However, PCNA index (%) was not statistically significant between the two groups (P = 0.802). Microphotometric evaluation of apoptotic index (AI) in terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-stained tissue after hepatotectomy for 3h, the AI% level in the hydrogen was significantly low to Contrast-group (P = 0.012). There were no significant difference between Hydrogen-group and Contrast-group at pre-operation (P = 0.653, P = 0.423), but after massive hepatotectomy, the TNF-α and IL-6 levels increase, and its in Hydrogen-group was significantly low compared with Contrast-group (P = 0.022, P = 0.013, vs P = 0.016, P = 0.012), respectively. Hydrogen-gas inhalation reduce levels of these markers and relieved morphological liver injury and apoptosis.
CONCLUSION: H2 gas attenuates markedly ischemia and portal hyperperfusion injury in pigs with massive hepatotectomy, possibly by the reduction of inflammation and oxidative stress, maybe a potential agent for treatment in clinic.
PMCID: PMC3468851  PMID: 23066313
Massive hepatotectomy; Hydrogen gas; Anti-oxidant; Hyperperfusion; Malondialdehyde; Oxidative stress
18.  Functional Expansion of the tRNA World Under Stress 
Molecular cell  2011;43(4):500-502.
Emerging mechanism for tRNA fragment-based translational regulation expands our understanding of the non-decoding roles of tRNA.
PMCID: PMC3163667  PMID: 21855789
19.  Bis(4′-chloro-2,2′:6′,2′′-terpyridine-κ3 N,N′,N′′)ruthenium(II) dichloride dihydrate 
In the cation of the title compound, [Ru(C15H10ClN3)2]Cl2·2H2O, the metal atom exhibits a distorted octa­hedral coordination geometry provided by the N atoms of two tridentate terpyridine ligands. The ligands are approximately planar [maximum deviation = 0.156 (5) Å] and form a dihedral angle of 87.0 (3)°. In the crystal, the cations, anions and water mol­ecules are linked into a three-dimensional network by C—H⋯Cl, C—H⋯O and O—H⋯Cl hydrogen bonds.
PMCID: PMC3379109  PMID: 22719330
20.  Hypoxia-inducible factor-2a is associated with ABCG2 expression, histology-grade and Ki67 expression in breast invasive ductal carcinoma 
Diagnostic Pathology  2012;7:32.
Breast cancer is the most common cancer and the leading cause of cancer mortality in women worldwide. Hypoxia is an important factor involved in the progression of solid tumors and has been associated with various indicators of tumor metabolism, angiogenesis and metastasis. But little is known about the contribution of Hypoxia-Inducible Factor-2a (HIF-2a) to the drug resistance and the clinicopathological characteristics in breast cancer.
Immunohistochemistry was employed on the tissue microarray paraffin sections of surgically removed samples from 196 invasive breast cancer patients with clinicopathological data. The correlations between the expression of HIF-2a and ABCG2 as well as other patients' clinicopathological data were investigated.
The results showed that HIF-2a was expressed in different intensities and distributions in the tumor cells of the breast invasive ductal carcinoma. A positive staining for HIF-2a was defined as a brown staining observed mainly in the nucleus. A statistically significant correlation was demonstrated between HIF-2a expression and ABCG2 expression (p = 0.001), histology-grade (p = 0.029), and Ki67 (p = 0. 043) respectively.
HIF-2a was correlated with ABCG2 expression, histology-grade and Ki67 expression in breast invasive ductal carcinoma. HIF-2a could regulate ABCG2 in breast cancer cells, and could be a novel potential bio-marker to predict chemotherapy effectiveness. The hypoxia/HIF-2a/ABCG2 pathway could be a new mechanism of breast cancer multidrug-resistance.
Virtual slides
PMCID: PMC3337233  PMID: 22452996
HIF-2a; ABCG2(BCRP); Histology-grade; Ki67; Breast invasive ductal cancer; IHC; Tissue microarray; MDR
21.  Expression of Glioma-associated Oncogene Homolog 1 is Associated with Invasion and Postoperative Liver Metastasis in Colon Cancer 
Objective: To investigate the expression of glioma-associated oncogene homolog 1(Gli-1) in colon cancer and its association with clinicopathological parameters and postoperative liver metastasis.
Methods: Expression of Gli-1 was detected by immunohistochemistry in paraffin-embedded specimens of 96 cases of colon cancer. Relationship between Gli-1 expression and clinicopathological parameters, postoperative liver metastasis were analyzed.
Results: Gli-1 protein expression was significantly increased in colon cancer tissues compared to normal colon tissues (P = 0.037). Gli-1 expression in colon tissues was increased in patients with lymph node metastases (P = 0.022) and higher T stages (P = 0.030). Postoperative live metastasis-free survival period was significantly longer in low Gli-1 expression group than that of high Gli-1 expression group (48.22±10.03 months vs 20.46±6.32 months, P=0.001). Multivariate analysis showed that Gli-1 expression level is an independent prognostic factor for postoperative live metastasis-free survival.
Conclusion: Colon cancer is associated with an upregulation of Gli-1 protein expression in colon tissues. In patients with colon cancer, Gli-1 expression level is closely related to lymph node metastases, T stages and postoperative live metastasis-free survival periods, indicative of a possible role of Gli-1 expression in colon cancer progression.
PMCID: PMC3384915  PMID: 22745574
Colon neoplasm; Glioma-associated oncogene 1; Liver metastasis.
22.  Packaging HIV Virion Components Through Dynamic Equilibria of a Human tRNA Synthetase 
The journal of physical chemistry. B  2010;114(49):16273-16279.
Aminoacyl tRNA synthetases, components of the translation apparatus, have alternative functions outside of translation. The structural and mechanistic basis of these alternative functions is of great interest. As an example, reverse transcription of the HIV genome is primed by a human lysine-specific tRNA (tRNALys3) that is packaged (into the virion) by the HIV gag protein with lysyl-tRNA synthetase (LysRS). Not understood is the structural basis for simultaneous packaging of tRNALys3, LysRS and Gag. Here ab initio computational methods, together with our recent high resolution 3-D structure of human LysRS, produced an energy-minimized model where Gag, tRNALys, and LysRS form a ternary complex. Interestingly, the model requires normally homodimeric LysRS to dissociate into a monomer that bridges between Gag and tRNALys3. Earlier experiments of others, and new experiments presented here, which tested an engineered dissociated form of LysRS, were consistent with the ab initio ‘bridging -monomer’ model. The results support an emerging theme that alterative functions of tRNA synthetases may come in part from protein surfaces exposed by dynamic equilibria.
PMCID: PMC3042951  PMID: 21058683
23.  Charcot-Marie-Tooth–Linked Mutant GARS Is Toxic to Peripheral Neurons Independent of Wild-Type GARS Levels 
PLoS Genetics  2011;7(12):e1002399.
Charcot-Marie-Tooth disease type 2D (CMT2D) is a dominantly inherited peripheral neuropathy caused by missense mutations in the glycyl-tRNA synthetase gene (GARS). In addition to GARS, mutations in three other tRNA synthetase genes cause similar neuropathies, although the underlying mechanisms are not fully understood. To address this, we generated transgenic mice that ubiquitously over-express wild-type GARS and crossed them to two dominant mouse models of CMT2D to distinguish loss-of-function and gain-of-function mechanisms. Over-expression of wild-type GARS does not improve the neuropathy phenotype in heterozygous Gars mutant mice, as determined by histological, functional, and behavioral tests. Transgenic GARS is able to rescue a pathological point mutation as a homozygote or in complementation tests with a Gars null allele, demonstrating the functionality of the transgene and revealing a recessive loss-of-function component of the point mutation. Missense mutations as transgene-rescued homozygotes or compound heterozygotes have a more severe neuropathy than heterozygotes, indicating that increased dosage of the disease-causing alleles results in a more severe neurological phenotype, even in the presence of a wild-type transgene. We conclude that, although missense mutations of Gars may cause some loss of function, the dominant neuropathy phenotype observed in mice is caused by a dose-dependent gain of function that is not mitigated by over-expression of functional wild-type protein.
Author Summary
Mutations in the glycyl-tRNA synthetase gene (GARS) cause Charcot-Marie-Tooth disease type 2D, a disease characterized by neuronal axon loss in the arms and legs, resulting in weakness and sensory problems. The GARS protein is essential for protein synthesis in every cell, and it has been difficult to determine whether the mutations result in disease because they impair this function or whether GARS somehow becomes toxic when it is mutated. We generated mice that overexpress normal GARS and mated these to two different mouse models of the disease to determine whether a restoration of normal function could prevent the disease. These crosses demonstrated that the mutant forms of GARS are toxic, and this toxic effect increases as the amount of mutant protein increases. Furthermore, this toxicity cannot be reduced or prevented by providing additional normal GARS. Therefore, these results suggest that, for most patients, therapies need to specifically target the mutant form of GARS or the toxic function.
PMCID: PMC3228828  PMID: 22144914
24.  Neck Circumference Positively Related With Central Obesity, Overweight, and Metabolic Syndrome in Chinese Subjects With Type 2 Diabetes: Beijing Community Diabetes Study 4 
Diabetes Care  2010;33(11):2465-2467.
To investigate the association between neck circumference and central obesity, overweight, and metabolic syndrome in Chinese individuals with type 2 diabetes.
A total of 3,182 diabetic subjects (aged 20–80 years) were recruited from 15 community health centers in Beijing using a multistage random sampling approach.
Receiver operating characteristic analysis showed that the area under the curve for neck circumference and central obesity was 0.77 for men and 0.75 for women (P < 0.001). Furthermore, a neck circumference of ≥38 cm for men and ≥35 cm for women was the best cutoff point for determining overweight subjects. A neck circumference of ≥39 cm for men and ≥35 cm for women was the best cutoff point to determine subjects with metabolic syndrome.
In the present study, neck circumference is positively related with BMI, waist circumference, and metabolic syndrome in Chinese individuals with type 2 diabetes.
PMCID: PMC2963514  PMID: 20724650
25.  ABCG2 is associated with HER-2 Expression, lymph node metastasis and clinical stage in breast invasive ductal carcinoma 
Diagnostic Pathology  2011;6:90.
ABCG2 is an ABC transporter. It has been demonstrated that endogenous ABCG2 expression in certain cancers is a possible reflection of the differentiated phenotype of the cell of origin and likely contributes to intrinsic drug resistance. But little is known about the contribution of ABCG2 to the drug resistance and the clinicopathological characteristics in breast cancer. In the present study, we investigated the expression of ABCG2 and the correlations between ABCG2 expression and patients' clinicopathological and biological characteristics.
Immunohistochemistry was employed on the tissue microarray paraffin sections of surgically removed samples from 196 breast cancer patients with clinicopathological data.
The results showed that ABCG2 was expressed in different intensities and distributions in the tumor cells of the breast invasive ductal carcinoma. A positive stain for ABCG2 was defined as a brown stain observed in the cytoplasm and cytomembrane. A statistically significant correlation was demonstrated between ABCG2 expression and HER-2 expression (p = 0.001), lymph node metastasis (p = 0.049), and clinical stage (p = 0.015) respectively.
ABCG2 correlated with Her-2 expression, lymph node metastasis and clinical stage in breast invasive ductal carcinoma. It could be a novel potential bio-marker which can predict biological behavior, clinical progression, prognosis and chemotherapy effectiveness.
PMCID: PMC3191358  PMID: 21943250
ABCG2(BCRP); Her-2; Lymph node metastasis; Clinical stage; Correlation; Breast invasive ductal cancer; Immunohistochemistry; Tissue microarray

Results 1-25 (41)