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1.  Engineered Human Muscle Tissue from Skeletal Muscle Derived Stem Cells and Induced Pluripotent Stem Cell Derived Cardiac Cells 
During development, cardiac and skeletal muscle share major transcription factors and sarcomere proteins which were generally regarded as specific to either cardiac or skeletal muscle but not both in terminally differentiated adult cardiac or skeletal muscle. Here, we investigated whether artificial muscle constructed from human skeletal muscle derived stem cells (MDSCs) recapitulates developmental similarities between cardiac and skeletal muscle. We constructed 3-dimensional collagen-based engineered muscle tissue (EMT) using MDSCs (MDSC-EMT) and compared the biochemical and contractile properties with EMT using induced pluripotent stem (iPS) cell-derived cardiac cells (iPS-EMT). Both MDSC-EMT and iPS-EMT expressed cardiac specific troponins, fast skeletal muscle myosin heavy chain, and connexin-43 mimicking developing cardiac or skeletal muscle. At the transcriptional level, MDSC-EMT and iPS-EMT upregulated both cardiac and skeletal muscle-specific genes and expressed Nkx2.5 and Myo-D proteins. MDSC-EMT displayed intracellular calcium ion transients and responses to isoproterenol. Contractile force measurements of MDSC-EMT demonstrated functional properties of immature cardiac and skeletal muscle in both tissues. Results suggest that the EMT from MDSCs mimics developing cardiac and skeletal muscle and can serve as a useful in vitro functioning striated muscle model for investigation of stem cell differentiation and therapeutic options of MDSCs for cardiac repair.
PMCID: PMC3984572
2.  One family cluster of avian influenza A(H7N9) virus infection in Shandong, China 
The first case of human infection with avian influenza A (H7N9) virus was identified in March, 2013 and the new H7N9 virus infected 134 patients and killed 45 people in China as of September 30, 2013. Family clusters with confirmed or suspected the new H7N9 virus infection were previously reported, but the family cluster of H7N9 virus infection in Shandong Province was first reported.
Case presentation
A 36-year-old man was admitted to Zaozhuang City Hospital with progressive respiratory distress and suspicion of impending acute respiratory distress syndrome on April 21. The chest radiography revealed bilateral ground-glass opacities and pulmonary lesions. The second case, the first case’s 4 year old son, was admitted to the same hospital on April 28 with fever and multiple patchy shadows in the bilateral lungs. Both of the two cases were confirmed to infect with H7N9 virus by the results of real-time reverse transcriptase-polymerase-chain reaction (rRT-PCR), virus isolation and serum antibody titer. At the same time, one environment samples was detected positive for H7N9 virus in the living poultry market in Zaozhuang. The homologous analysis of the full genome sequence indicated that both viruses from the patients were almost genetically identical. The field epidemiology investigation showed that the two cases had no recognized exposure to poultry, but had the exposure to the environment. The second case had substantial unprotected close exposure to his ill father and developed symptoms seven days after his last contact with his father. After surgery, the index case and his son were discharged on May 16 and May 6, respectively. 11 close contacts of both patients were identified and tested negative both the throat swabs and the serum antibody.
The infection of the index case probably resulted from contact with environmentally contaminated material. For the son, the probable infection source was from the index case during unprotected exposure, but the possibility from the environment or other sources could not be completely ruled out.
PMCID: PMC3974040  PMID: 24559386
Avian Influenza A (H7N9) virus; Epidemiology; Infectious source
3.  Identification of Human Tissue Kallikrein 6 as a Potential Marker of Laryngeal Cancer Based on the Relevant Secretory/Releasing Protein Database 
Disease Markers  2014;2014:594093.
Objective. This study was aimed to create a large-scale laryngeal cancer relevant secretory/releasing protein database and further discover candidate biomarkers. Methods. Primary tissue cultures were established using tumor tissues and matched normal mucosal tissues collected from four laryngeal cancer patients. Serum-free conditioned medium (CM) samples were collected. These samples were then sequentially processed by SDS-PAGE separation, trypsin digestion, and LC-MS/MS analysis. The candidates in the database were validated by ELISA using plasma samples from laryngeal cancer patients, benign patients, and healthy individuals. Results. Combining MS data from the tumor tissues and normal tissues, 982 proteins were identified in total; extracellular proteins and cell surface proteins accounted for 15.0% and 4.3%, respectively. According to stringent criteria, 49 proteins were selected as candidates worthy of further validation. Of these, human tissue kallikrein 6 (KLK6) was verified. The level of KLK6 was significantly increased in the plasma samples from the cancer cohort compared to the benign and healthy cohorts and moreover showed a slight decrease in the postoperative plasma samples in comparison to the preoperative plasma samples. Conclusions. This laryngeal cancer-derived protein database provides a promising repository of candidate blood biomarkers for laryngeal cancer. The diagnostic potential of KLK6 deserves further investigation.
PMCID: PMC3942293  PMID: 24669031
4.  Impact of Bariatric Surgery on Ghrelin and Obestatin Levels in Obesity or Type 2 Diabetes Mellitus Rat Model 
Journal of Diabetes Research  2014;2014:569435.
We aimed to evaluate the therapeutic efficacy on weight control by different bariatric surgeries and investigate the ghrelin and obestatin changes after these surgeries in obesity and nonobese type 2 diabetes mellitus (T2DM) rats. Obese rats were randomly assigned to receive sleeve gastrectomy (SG, n = 8), minigastric bypass (MGBP, n = 8), roux-en-Y gastric bypass (RYGBP, n = 8), and sham operation (SO, n = 4). Another 4 rats served as control. Besides, Goto-Kakisaki (GK) rats were also randomly divided into similar groups except for total gastrectomy (TG, n = 8) group. The results showed that in obese rats, weigh loss in RYGBP group was similar to that in MGBP group but larger than that in SG group. Ghrelin significantly increased in RYGB group, but obestatin increased in MGBP group. Ghrelin/obestatin ratio significantly decreased in SG group. In GK rats, weight loss was most obvious in TG group. Postoperatively, ghrelin was significantly increased in MGBP and RYGB groups but decreased in TG group. Obestatin also showed an increase in MGBP and RYGB groups. Ghrelin/obestatin in TG group decreased significantly. In conclusion, RYGB and MGBP may be more suitable for obese rats, but TG may be the best strategy for T2DM rats to control weight with different mechanisms.
PMCID: PMC3941146  PMID: 24672803
5.  Adrenomedullin-RAMP2 System Suppresses ER Stress-Induced Tubule Cell Death and Is Involved in Kidney Protection 
PLoS ONE  2014;9(2):e87667.
Various bioactive peptides have been implicated in the homeostasis of organs and tissues. Adrenomedullin (AM) is a peptide with various bioactivities. AM-receptor, calcitonin-receptor-like receptor (CLR) associates with one of the subtypes of the accessory proteins, RAMPs. Among the RAMP subisoforms, only RAMP2 knockout mice (−/−) reproduce the phenotype of embryonic lethality of AM−/−, illustrating the importance of the AM-RAMP2-signaling system. Although AM and RAMP2 are abundantly expressed in kidney, their function there remains largely unknown. We used genetically modified mice to assess the pathophysiological functions of the AM-RAMP2 system. RAMP2+/− mice and their wild-type littermates were used in a streptozotocin (STZ)-induced renal injury model. The effect of STZ on glomeruli did not differ between the 2 types of mice. On the other hand, damage to the proximal urinary tubules was greater in RAMP2+/−. Tubular injury in RAMP2+/− was resistant to correction of blood glucose by insulin administration. We examined the effect of STZ on human renal proximal tubule epithelial cells (RPTECs), which express glucose transporter 2 (GLUT2), the glucose transporter that specifically takes up STZ. STZ activated the endoplasmic reticulum (ER) stress sensor protein kinase RNA-like endoplasmic reticulum kinase (PERK). AM suppressed PERK activation, its downstream signaling, and CCAAT/enhancer-binding homologous protein (CHOP)-induced cell death. We confirmed that the tubular damage was caused by ER stress-induced cell death using tunicamycin (TUN), which directly evokes ER stress. In RAMP2+/− kidneys, TUN caused severe injury with enhanced ER stress. In wild-type mice, TUN-induced tubular damage was reversed by AM administration. On the other hand, in RAMP2+/−, the rescue effect of exogenous AM was lost. These results indicate that the AM-RAMP2 system suppresses ER stress-induced tubule cell death, thereby exerting a protective effect on kidney. The AM-RAMP2 system thus has the potential to serve as a therapeutic target in kidney disease.
PMCID: PMC3914859  PMID: 24505304
6.  Novel One-pot Fabrication of Lab-on-a-Bubble@Ag Substrate without Coupling-agent for Surface Enhanced Raman Scattering 
Scientific Reports  2014;4:3942.
Through in-situ reduction of silver nitrate without using any coupling-agent, a substrate for surface-enhanced Raman scattering (SERS) was prepared by coating silver on hollow buoyant silica microspheres as a lab on a bubble (LoB). The silver coated LoBs (LoBs@Ag) floated on surface of a solution could provide a very convenient platform for the detection of target molecules in the solution. The LoBs@Ag substrate not only immobilized well-distributed Ag nanoparticles on the surface LoBs, but excluded the interference of coupling agents. This yielded high-resolution SERS spectra with excellent reproducibility. The adsorption of crystal violet (CV) on the LoBs@Ag substrate was investigated by means of SERS combined with density functional theory (DFT) calculations. The LoBs@Ag substrate exhibited a remarkable Raman enhancement effect for CV with an enhancement factor of 6.9 × 108 and wide adaptability from dye, pesticide to bio-molecules. On the basis of this substrate, a simple and sensitive SERS method was proposed for the determination of trace organic pollutants or bio-molecules.
PMCID: PMC3909904  PMID: 24487575
7.  In Vitro Evaluation of the Antiviral Activity of the Synthetic Epigallocatechin Gallate Analog-Epigallocatechin Gallate (EGCG) Palmitate against Porcine Reproductive and Respiratory Syndrome Virus 
Viruses  2014;6(2):938-950.
In this study, epigallocatechin gallate (EGCG) palmitate was synthesized and its anti-porcine reproductive and respiratory syndrome virus (PRRSV) activity was studied. Specifically, EGCG palmitate was evaluated for its ability to inhibit PRRSV infection in MARC-145 cells when administered as pre-, post-, or co-treatment. EGCG and ribavirin were used as controls. The results showed that a 50% cytotoxic concentration (CC50) of EGCG, EGCG palmitate, and ribavirin was achieved at 2,359.71, 431.42, and 94.06 μM, respectively. All three drugs inhibited PRRSV in a dose-dependent manner regardless of the treatment protocol. EGCG palmitate exhibited higher cytotoxicity than EGCG, but lower cytotoxicity than ribavirin. EGCG palmitate anti-PRRSV activity was significantly higher than that of EGCG and ribavirin, both as pre-treatment and post-treatment. Under the former conditions and a tissue culture infectious dose of 10 and 100, the selectivity index (SI) of EGCG palmitate in the inhibition of PRRSV was 3.8 and 2.9 times higher than that of ribavirin when administered as a pre-treatment, while the SI of EGCG palmitate in the inhibition of PRRSV was 3.0 and 1.9 times higher than ribavirin when administered as a post-treatment. Therefore, EGCG palmitate is potentially effective as an anti-PRRSV agent and thus of interest to the pharmaceutical industry.
PMCID: PMC3939490  PMID: 24566281
EGCG palmitate; synthesized; anti-PRRSV; MARC-145 cells
8.  Preparation and Characterization of Tripterygium wilfordii Multi-Glycoside Nanoparticle Using Supercritical Anti-Solvent Process 
The aim of this study was to prepare nanosized Tripterygium wilfordii multi-glycoside (GTW) powders by the supercritical antisolvent precipitation process (SAS), and to evaluate the anti-inflammatory effects. Ethanol was used as solvent and carbon dioxide was used as an antisolvent. The effects of process parameters such as precipitation pressure (15–35 MPa), precipitation temperature (45–65 °C), drug solution flow rates (3–7 mL/min) and drug concentrations (10–30 mg/mL) were investigated. The nanospheres obtained with mean diameters ranged from 77.5 to 131.8 nm. The processed and unprocessed GTW were characterized by scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy and thermal gravimetric analysis. The present study was designed to investigate the beneficial effect of the GTW nanoparticles on adjuvant-induced arthritis in albino rats. The processed and unprocessed GTW were tested against Freund’s complete adjuvant-induced arthritis in rats. Blood samples were collected for the estimation of interleukins (IL-1α, IL-1β) and tumor necrosis factor-α (TNF-α). It was concluded that physicochemical properties and anti-inflammatory activity of GTW nanoparticles could be improved by physical modification, such as particle size reduction using supercritical antisolvent (SAS) process. Further, SAS process was a powerful methodology for improving the physicochemical properties and anti-inflammatory activity of GTW.
PMCID: PMC3958876  PMID: 24549173
multi-glycoside; nanoparticle; supercritical antisolvent; physicochemical property; Tripterygium wilfordii
9.  PTOP and TRF1 help enhance the radio resistance in breast cancer cell 
The telomere binding proteins play an important role in telomere function, which contribute greatly to the radio resistant in human cancers. This research is designed to investigate the relationship among the telomere length, telomerase activity and changes of telomere binding protein PTOP and TRF1 in radio resistant breast cancer cell lines.
Irradiate MDA-MB-435 s breast cancer cell with total dose of 60 Gy delivered in 2 Gy/fraction and 6 Gy/fraction respectively, then measuring their telomere length by Southern blot analysis,telomerase activity by Telomerase PCR Elisa and detecting the expression of PTOP and TRF1 in both gene and protein levels. To further investigate the function of PTOP, using lentivirus technic to silence the PTOP gene and the detected the new silenced cells by southern blot and telomerase activity.
2 radio resistant breast cancer cell lines were successfully established. The MDA-MB-435 s R60/6 was (approximate 8.1-8.6 kbp) about 2–2.4 folds to the patent cell (3.6-4.2 kbp), the MDA-MB-435 s R60/2 cell (approximate 5.3-6.3 kbp) was about 1.3-1.75 fold to the parent cell line. The telomerase activity was more enhanced in radio resistant cell lines than the parent cell. The expression of PTOP and TRF1 were significant increased in radio resistant cell lines than the patent cell in both gene and protein level. Otherwise, after using lentivirus technic to silence the PTOP gene, we found the radio resistant cell lines were significant decrease their radio resistances and telomerase activities.
The telomere binding protein PTOP and TRF1 were increased expressed in radio resistant breast cancer cell, PTOP was observed instinct positive correlated with telomere lengthen and telomerase activity enhancement.
PMCID: PMC3984749  PMID: 24460895
PTOP; TRF1; Telomere bonding protein; Telomere; Radio resistant
10.  The Incidence of Liver Injury in Uyghur Patients Treated for TB in Xinjiang Uyghur Autonomous Region, China, and Its Association with Hepatic Enzyme Polymorphisms NAT2, CYP2E1, GSTM1 and GSTT1 
PLoS ONE  2014;9(1):e85905.
Background and Objective
Of three first-line anti-tuberculosis (anti-TB) drugs, isoniazid is most commonly associated with hepatotoxicity. Differences in INH-induced toxicity have been attributed to genetic variability at several loci, NAT2, CYP2E1, GSTM1and GSTT1, that code for drug-metabolizing enzymes. This study evaluated whether the polymorphisms in these enzymes were associated with an increased risk of anti-TB drug-induced hepatitis in patients and could potentially be used to identify patients at risk of liver injury.
Methods and Design
In a cross-sectional study, 2244 tuberculosis patients were assessed two months after the start of treatment. Anti-TB drug-induced liver injury (ATLI) was defined as an ALT, AST or bilirubin value more than twice the upper limit of normal. NAT2, CYP2E1, GSTM1 and GSTT1 genotypes were determined using the PCR/ligase detection reaction assays.
2244 patients were evaluated, there were 89 cases of ATLI, a prevalence of 4% 9 patients (0.4%) had ALT levels more than 5 times the upper limit of normal. The prevalence of ATLI was greater among men than women, and there was a weak association with NAT2*5 genotypes, with ATLI more common among patients with the NAT2*5*CT genotype. The sensitivity of the CT genotype for identifying patients with ATLI was 42% and the positive predictive value 5.9%. CT ATLI was more common among slow acetylators (prevalence ratio 2.0 (95% CI 0.95,4.20) )compared to rapid acetylators. There was no evidence that ATLI was associated with CYP2E1 RsaIc1/c1genotype, CYP2E1 RsaIc1/c2 or c2/c2 genotypes, or GSTM1/GSTT1 null genotypes.
In Xinjiang Uyghur TB patients, liver injury was associated with the genetic variant NAT2*5, however the genetic markers studied are unlikely to be useful for screening patients due to the low sensitivity and low positive predictive values for identifying persons at risk of liver injury.
PMCID: PMC3900431  PMID: 24465778
11.  eRF3b, a Biomarker for Hepatocellular Carcinoma, Influences Cell Cycle and Phosphoralation Status of 4E-BP1 
PLoS ONE  2014;9(1):e86371.
Hepatitis B virus (HBV) infection and its sequelae are now recognized as serious problems globally. Our aime is to screen hepatocellular carcinoma (HCC) from chronic hepatitis B (CHB) and identify the characteristics of proteins involved.
Methodology/Principal Findings
We affinity-purified sample serum with weak cation-exchange (WCX) magnetic beads and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) analysis to search for potential markers. The 4210 Da protein, which differed substantially between HCC and CHB isolates, was later identified to be eukaryotic peptide chain release factor GTP-binding subunit eRF3b. Further research showed that eRF3b/GSPT2 was positively expressed in liver tissues. GSPT2 mRNA was, however differentially expressed in blood. Compared with normal controls, the relative expression of GSPT2/18s rRNA was higher in CHB patients than in patients with either LC or HCC (P = 0.035 for CHB vs. LC; P = 0.020 for CHB vs. HCC). The data of further research showed that eRF3b/GSPT2 promoted the entrance of the HepG2 cells into the S-phase and that one of the substrates of the mTOR kinase, 4E-BP1, was hyperphosphorylated in eRF3b-overexpressing HepG2 cells.
Overall, the differentially expressed protein eRF3b, which was discovered as a biomarker for HCC, could change the cell cycle and influence the phosphorylation status of 4E-BP1 on Ser65 in HepG2.
PMCID: PMC3900531  PMID: 24466059
12.  Protein-Protein Interactions Prediction Based on Iterative Clique Extension with Gene Ontology Filtering 
The Scientific World Journal  2014;2014:523634.
Cliques (maximal complete subnets) in protein-protein interaction (PPI) network are an important resource used to analyze protein complexes and functional modules. Clique-based methods of predicting PPI complement the data defection from biological experiments. However, clique-based predicting methods only depend on the topology of network. The false-positive and false-negative interactions in a network usually interfere with prediction. Therefore, we propose a method combining clique-based method of prediction and gene ontology (GO) annotations to overcome the shortcoming and improve the accuracy of predictions. According to different GO correcting rules, we generate two predicted interaction sets which guarantee the quality and quantity of predicted protein interactions. The proposed method is applied to the PPI network from the Database of Interacting Proteins (DIP) and most of the predicted interactions are verified by another biological database, BioGRID. The predicted protein interactions are appended to the original protein network, which leads to clique extension and shows the significance of biological meaning.
PMCID: PMC3919085  PMID: 24578640
14.  Analysis and therapeutic schedule of the postoperative recurrence of bone tuberculosis 
The present study aims to analyze the main reasons that lead to the failure of bone tuberculosis (TB) surgery and the efficacy of reoperation.
A total of 3,000 cases of bone TB patients were examined retrospectively. Of these, 180 cases had recurrence, including 135 cases of spinal TB and 45 cases of limb TB. Preoperative indicators of duration of anti-TB chemotherapy, nutritional conditions, temperature conditions and erythrocyte sedimentation rate, and medication time of postoperative and recurrence were statistically analyzed.
Of all 180 cases with reoperation, 176 cases were cured, and four paralyzed patients were symptomatically improved. The causes of postoperative recurrence of bone TB were relatively complex. Efficacy of reoperation was evaluated. Shorter chemotherapy duration, long-term illness, poor health, a higher body temperature, and an accelerated ESR are likely to increase the risk of recurrence.
Given the operation failure, careful analysis of the failure reasons and the targeted reoperation can obtain satisfactory results, thereby avoiding the failure of the initial surgery.
PMCID: PMC3878563  PMID: 24341624
Bone tuberculosis; Recurrence; Reoperation; Therapeutic schedule
15.  Correction: Transcriptome Analysis of Medicinal Plant Salvia miltiorrhiza and Identification of Genes Related to Tanshinone Biosynthesis 
PLoS ONE  2013;8(12):10.1371/annotation/fd65b655-d35b-47d1-8793-07da2273c144.
PMCID: PMC3866330
16.  Overexpression of HIF-1α, metallothionein and SLUG is associated with high TNM stage and lymph node metastasis in papillary thyroid carcinoma 
Hypoxia inducible factor-1α (HIF-1α) is upregulated by hypoxia, and involved in tumor growth and metastasis in many malignant tumors including papillary thyroid carcinoma (PTC). Metallothionein (MT) is a group of small molecular weight cysteine-rich proteins with a broad variety of functions. SLUG is a member of SNAIL superfamily of zinc finger transcriptional factors implicated in epithelial-mesenchymal transition (EMT). The purpose of this study was to examine HIF-1α, MT and SLUG expression in PTC and assess association of their expression with clinicopathological indicators. HIF-1α, MT and SLUG protein expression in 129 PTCs, 61 nodular hyperplasia and 118 normal thyroid tissue specimens were analyzed using immunohistochemistry. The protein expression levels of these three molecules were up-regulated in PTCs. High protein expression of HIF-1α, MT and SLUG was significantly correlated with high TNM stage (P=0.003, 0.002, 0.024, respectively) and lymph node metastasis (LNM) (P<0.001 for all three molecules). Furthermore, HIF-1α, MT and SLUG protein expression were correlated with one another. Concomitant high expression of any two of these three molecules had stronger correlation with high TNM stage (P≤0.001 for HIF-1α/MT, MT/SLUG and HIF-1α/SLUG) and LNM (P=0.008, 0.002, 0.019 for HIF-1α/MT, MT/SLUG and HIF-1α/SLUG, respectively) than did each alone, and concomitant high expression of all these three molecules is signifi cantly associated with high TNM stage and LNM as compared with cases not showing such expression (P<0.001). These results demonstrated that the evaluation of HIF-1α, MT and SLUG expression in PTC may be useful in predicting the risk of LNM and high TNM stage.
PMCID: PMC3885487  PMID: 24427353
Hypoxia inducible factor-1α; metallothionein; SLUG; papillary thyroid carcinoma
17.  Tonoplast calcium sensors CBL2 and CBL3 control plant growth and ion homeostasis through regulating V-ATPase activity in Arabidopsis 
Cell Research  2012;22(12):1650-1665.
Plant responses to developmental and environmental cues are often mediated by calcium (Ca2+) signals that are transmitted by diverse calcium sensors. The calcineurin B-like (CBL) protein family represents calcium sensors that decode calcium signals through specific interactions with a group of CBL-interacting protein kinases. We report functional analysis of Arabidopsis CBL2 and CBL3, two closely related CBL members that are localized to the vacuolar membrane through the N-terminal tonoplast-targeting sequence. While cbl2 or cbl3 single mutant did not show any phenotypic difference from the wild type, the cbl2 cbl3 double mutant was stunted with leaf tip necrosis, underdeveloped roots, shorter siliques and fewer seeds. These defects were reminiscent of those in the vha-a2 vha-a3 double mutant deficient in vacuolar H+-ATPase (V-ATPase). Indeed, the V-ATPase activity was reduced in the cbl2 cbl3 double mutant, connecting tonoplast CBL-type calcium sensors to the regulation of V-ATPase. Furthermore, cbl2 cbl3 double mutant was compromised in ionic tolerance and micronutrient accumulation, consistent with the defect in V-ATPase activity that has been shown to function in ion compartmentalization. Our results suggest that calcium sensors CBL2 and CBL3 serve as molecular links between calcium signaling and V-ATPase, a central regulator of intracellular ion homeostasis.
PMCID: PMC3515760  PMID: 23184060
calcium sensor; tonoplast; V-ATPase; ion homeostasis; V-ATPase
18.  Telomere-Binding Protein TPP1 Modulates Telomere Homeostasis and Confers Radioresistance to Human Colorectal Cancer Cells 
PLoS ONE  2013;8(11):e81034.
Radiotherapy is one of the major therapeutic strategies in cancer treatment. The telomere-binding protein TPP1 is an important component of the shelterin complex at mammalian telomeres. Our previous reports showed that TPP1 expression was elevated in radioresistant cells, but the exact effects and mechanisms of TPP1 on radiosensitivity is unclear.
Principal Findings
In this study, we found that elevated TPP1 expression significantly correlated with radioresistance and longer telomere length in human colorectal cancer cell lines. Moreover, TPP1 overexpression showed lengthened telomere length and a significant decrease of radiosensitivity to X-rays. TPP1 mediated radioresistance was correlated with a decreased apoptosis rate after IR exposure. Furthermore, TPP1 overexpression showed prolonged G2/M arrest mediated by ATM/ATR-Chk1 signal pathway after IR exposure. Moreover, TPP1 overexpression accelerated the repair kinetics of total DNA damage and telomere dysfunction induced by ionizing radiation.
We demonstrated that elevated expressions of TPP1 in human colorectal cancer cells could protect telomere from DNA damage and confer radioresistance. These results suggested that TPP1 may be a potential target in the radiotherapy of colorectal cancer.
PMCID: PMC3834294  PMID: 24260532
19.  Transcriptome Analysis of Medicinal Plant Salvia miltiorrhiza and Identification of Genes Related to Tanshinone Biosynthesis 
PLoS ONE  2013;8(11):e80464.
Salvia miltiorrhiza Bunge, a perennial plant of Lamiaceae, accumulates abietane-type diterpenoids of tanshinones in root, which have been used as traditional Chinese medicine to treat neuroasthenic insomnia and cardiovascular diseases. However, to date the biosynthetic pathway of tanshinones is only partially elucidated and the mechanism for their root-specific accumulation remains unknown. To identify enzymes and transcriptional regulators involved in the biosynthesis of tanshinones, we conducted transcriptome profiling of S. miltiorrhiza root and leaf tissues using the 454 GS-FLX pyrosequencing platform, which generated 550,546 and 525,292 reads, respectively. RNA sequencing reads were assembled and clustered into 64,139 unigenes (29,883 isotigs and 34,256 singletons). NCBI non-redundant protein databases (NR) and Swiss-Prot database searches anchored 32,096 unigenes (50%) with functional annotations based on sequence similarities. Further assignments with Gene Ontology (GO) terms and KEGG biochemical pathways identified 168 unigenes referring to the terpenoid backbone biosynthesis (including 144 MEP and MVA pathway genes and 24 terpene synthases). Comparative analysis of the transcriptomes identified 2,863 unigenes that were highly expressed in roots, including those encoding enzymes of early steps of tanshinone biosynthetic pathway, such as copalyl diphosphate synthase (SmCPS), kaurene synthase-like (SmKSL) and CYP76AH1. Other differentially expressed unigenes predicted to be related to tanshinone biosynthesis fall into cytochrome P450 monooxygenases, dehydrogenases and reductases, as well as regulatory factors. In addition, 21 P450 genes were selectively confirmed by real-time PCR. Thus we have generated a large unigene dataset which provides a valuable resource for further investigation of the radix development and biosynthesis of tanshinones.
PMCID: PMC3834075  PMID: 24260395
20.  Functional Genetic Polymorphisms in PP2A Subunit Genes Confer Increased Risks of Lung Cancer in Southern and Eastern Chinese 
PLoS ONE  2013;8(10):e77285.
Protein phosphatase-2A (PP2A) is one of the major cellular serine-threonine phosphatases and functions as a tumor suppressor that negatively regulates the activity of some oncogenic kinases. Recent studies have reported that PP2A expression was suppressed during lung carcinogenesis, we there hypothesized that the single nucleotide polymorphisms (SNPs) in PP2A subunit genes may affect PP2A function and thus contribute to lung cancer susceptibility. In a two-stage case-control study with a total of 1559 lung cancer patients and 1679 controls, we genotyped eight putative functional SNPs and one identified functional SNP (i.e., rs11453459) in seven major PP2A subunits (i.e., PPP2R1A, PPP2R1B, PPP2CA, PPP2R2A, PPP2R2B, PPP2R5C, PPP2R5E) in southern and eastern Chinese. We found that rs11453459G (-G/GG) variant genotypes of PPP2R1A and the rs1255722AA variant genotype of PPP2R5E conferred increased risks of lung cancer (rs11453459, -G/GG vs. –: OR = 1.31, 95% CI = 1.13–1.51; rs1255722, AA vs. AG/GG: OR = 1.27, 95% CI = 1.07–1.51). After combined the two variants, the number of the adverse genotypes was positively associated with lung cancer risk in a dose-response manner (Ptrend  = 5.63×10−6). Further functional assay showed that lung cancer tissues carrying rs1255722AA variant genotype had a significantly lower mRNA level of PPP2R5E compared with tissues carrying GG/GA genotypes. However, such effect was not observed for the other SNPs and other combinations. Our findings suggested that the two functional variants in PPP2R1A and PPP2R5E and their combination are associated with lung cancer risk in Chinese, which may be valuable biomarkers to predict risk of lung cancer.
PMCID: PMC3812212  PMID: 24204789
21.  Postischemic Long-Term Treatment with Qiangli Tianma Duzhong Capsule Improves Brain Functional Recovery via the Improvement of Hemorrheology and the Inhibition of Platelet Aggregation in a Rat Model of Focal Cerebral Ischemia 
Qiangli Tianma Duzhong capsule (TMDZ), a Chinese herbal drug, is clinically used to improve functional outcome in patients with ischemic stroke in China. This study was conducted to establish whether postischemic long-term treatment with TMDZ could reduce the loss of injured hemisphere and confer the improvements of neurological outcome in chronic survival of rats with 2 h middle cerebral artery occlusion (MCAO)/reperfusion brain injury and its primary mechanisms. We found that TMDZ (44.5, 89, or 178 mg/kg), administered per os 6 h after the onset of ischemia and for 28 consecutive days, significantly improved the behavior deficits, beginning on day 7, and further improved later. TMDZ treatment also markedly reduced the tissue loss of the injured hemisphere and improved histopathology. In the meantime, TMDZ treatment could improve hemorrheology and inhibit platelet aggregation. These results provide the first evidence that post-ischemic long-term treatment with TMDZ confers the improvements of neurological outcome and the loss of injured hemisphere in an animal ischemic stroke model, and its mechanisms might be associated with the improvements of hemorrheology and the inhibition of platelet aggregation.
PMCID: PMC3830819  PMID: 24319485
22.  Antitubercular nitrofuran isoxazolines with improved pharmacokinetic properties 
Bioorganic & medicinal chemistry  2012;20(20):6063-6072.
A series of tetracyclic nitrofuran isoxazoline antituberculosis agents was designed and synthesized to improve the pharmacokinetic properties of an initial lead compound, which had potent antituberculosis activity but suffered from poor solubility, high protein binding and rapid metabolism. In this study, structural modifications were carried on the outer phenyl and piperidine rings to introduce solubilizing and metabolically blocking functional groups. The compounds generated were evaluated for their in vitro antitubercular activity, bacterial spectrum of activity, solubility, permeability, microsomal stability and protein binding. Pharmacokinetic profiles for the most promising candidates were then determined. Compounds with phenyl morpholine and pyridyl morpholine outer rings were found to be the most potent antituberculosis agents in the series. These compounds retained a narrow antibacterial spectrum of activity, with weak anti-gram positive and no gram negative activity, as well as good activity against non-replicating M. tuberculosis in a low oxygen model. Overall, the addition of solubilizing and metabolically blocked outer rings did improve solubility and decrease protein binding as designed. However, the metabolic stability for compounds in this series was generally lower than desired. The best three compounds selected for in vivo pharmacokinetic testing all showed high oral bioavailability, with one notable compound showing a significantly longer half-life and good tolerability supporting its further advancement.
PMCID: PMC3582038  PMID: 22995771
Tuberculosis; antibiotic; nitrofuran; isoxazoline; nitroaromatic
23.  Human Infection with Eurasian Avian-like Influenza A(H1N1) Virus, China 
Emerging Infectious Diseases  2013;19(10):1709-1711.
PMCID: PMC3810748  PMID: 24050834
influenza; surveillance; serology; avian-like influenza A(H1N1); viruses
24.  Clinical and pathological analysis of the kidney in patients with hypertensive nephropathy 
The aim of the present study was to identify the association between pathological types of kidney and clinical manifestations in patients with hypertensive nephropathy. The blood pressure, fundus, urinalysis test results and renal function changes were analysed in patients who were treated for hypertensive nephropathy. Downward kidney puncture biopsy was performed using a 16G ejection needle with the aid of B ultrasound in 47 cases. The specimens were observed using light microscopy and immunofluorescence. The pathological changes observed in the patients exhibiting symptoms of hypertensive nephropathy varied. The majority of clinical manifestations were benign arteriolar nephrosclerosis, hyaline degeneration of the renal artery and the appearance of a thickened wall of a thickened renal artery wall. Severe cases showed malignant arteriolar nephrosclerosis characterised by fibrinoid necrosis of renal arterioles and intimal hyperplasia. In addition, in the severe cases, fibrinoid necrosis of the afferent arteriole and arcuate artery wall was observed, with severe interlobular artery and arcuate artery myointimal thickening. Renal biopsy in patients with hypertensive nephropathy is safe and feasible. The prognosis and treatment of pathological and clinical disease related to renal pathology is necessary.
PMCID: PMC3820837  PMID: 24223652
hypertensive; nephropathy; kidney; pathology
25.  Downregulation of miR-151-5p Contributes to Increased Susceptibility to Arrhythmogenesis during Myocardial Infarction with Estrogen Deprivation 
PLoS ONE  2013;8(9):e72985.
Estrogen deficiency is associated with increased incidence of cardiovascular diseases. But merely estrogen supplementary treatment can induce many severe complications such as breast cancer. The present study was designed to elucidate molecular mechanisms underlying increased susceptibility of arrhythmogenesis during myocardial infarction with estrogen deprivation, which provides us a new target to cure cardiac disease accompanied with estrogen deprivation. We successfully established a rat model of myocardial ischemia (MI) accompanied with estrogen deprivation by coronary artery ligation and ovariectomy (OVX). Vulnerability and mortality of ventricular arrhythmias increased in estrogen deficiency rats compared to non estrogen deficiency rats when suffered MI, which was associated with down-regulation of microRNA-151-5p (miR-151-5p). Luciferase Reporter Assay demonstrated that miR-151-5p can bind to the 3′-UTR of FXYD1 (coding gene of phospholemman, PLM) and inhibit its expression. We found that the expression of PLM was increased in (OVX+MI) group compared with MI group. More changes such as down-regulation of Kir2.1/IK1, calcium overload had emerged in (OVX+MI) group compared to MI group merely. Transfection of miR-151-5p into primary cultured myocytes decreased PLM levels and [Ca2+]i, however, increased Kir2.1 levels. These effects were abolished by the antisense oligonucleotides against miR-151-5p. Co-immunoprecipitation and immunofluorescent experiments confirmed the co-localization between Kir2.1 and PLM in rat ventricular tissue. We conclude that the increased ventricular arrhythmias vulnerability in response to acute myocardial ischemia in rat is critically dependent upon down-regulation of miR-151-5p. These findings support the proposal that miR-151-5p could be a potential therapeutic target for the prevention of ischemic arrhythmias in the subjects with estrogen deficiency.
PMCID: PMC3767733  PMID: 24039836

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