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1.  Suppression of Mic60 compromises mitochondrial transcription and oxidative phosphorylation 
Scientific Reports  2015;5:7990.
Precise regulation of mtDNA transcription and oxidative phosphorylation (OXPHOS) is crucial for human health. As a component of mitochondrial contact site and cristae organizing system (MICOS), Mic60 plays a central role in mitochondrial morphology. However, it remains unclear whether Mic60 affects mitochondrial transcription. Here, we report that Mic60 interacts with mitochondrial transcription factors TFAM and TFB2M. Furthermore, we found that Mic60 knockdown compromises mitochondrial transcription and OXPHOS activities. Importantly, Mic60 deficiency decreased TFAM binding and mitochondrial RNA polymerase (POLRMT) recruitment to the mtDNA promoters. In addition, through mtDNA immunoprecipitation (mIP)-chromatin conformation capture (3C) assays, we found that Mic60 interacted with mtDNA and was involved in the architecture of mtDNA D-loop region. Taken together, our findings reveal a previously unrecognized important role of Mic60 in mtDNA transcription.
PMCID: PMC4303897  PMID: 25612828
2.  Proportions of Staphylococcus aureus and Methicillin-Resistant Staphylococcus aureus in Patients with Surgical Site Infections in Mainland China: A Systematic Review and Meta-Analysis 
PLoS ONE  2015;10(1):e0116079.
Sufficient details have not been specified for the epidemiological characteristics of Staphylococcus aureus (S. aureus) and methicillin-resistant Staphylococcus aureus (MRSA) among surgical site infections (SSIs) in mainland China. This systematic review aimed to estimate proportions of S. aureus and MRSA in SSIs through available published studies.
PubMed, Embase and four Chinese electronic databases were searched to identify relevant primary studies published between 2007 and 2012. Meta-analysis was conducted on the basis of logit-transformed metric for proportions of S. aureus and MRSA, followed by pre-defined subgroup meta-analysis. Random-effects meta-regression was also conducted to explore the impact of possible factors on S. aureus proportions.
106 studies were included, of which 38 studies involved MRSA. S. aureus accounted for 19.1% (95%CI 17.2-21.0%; I2 = 84.1%) of all isolates in SSIs, which was roughly parallel to 18.5% in the United States (US) (P-value = 0.57) but significantly exceeded those calculated through the surveillance system in China (P-value<0.001). In subgroup analysis, S. aureus in patients with thoracic surgery (41.1%, 95%CI 26.3-57.7%; I2 = 74.4%) was more common than in those with gynecologic surgery (20.1%, 95%CI 15.6-25.6%; I2 = 33.0%) or abdominal surgery (13.8%, 95%CI 10.3-18.4%; I2 = 70.0%). Similar results were found in meta-regression. MRSA accounted for 41.3% (95%CI 36.5-46.3%; I2 = 64.6%) of S. aureus, significantly lower than that in the US (P-value = 0.001). MRSA was sensitive to vancomycin (522/522) and linezolid (93/94), while 79.9% (95%CI 67.4-88.4%; I2 = 0%) and 92.0% (95%CI 80.2-97.0%; I2 = 0%) of MRSA was resistant to clindamycin and erythromycin respectively.
The overall proportion of S. aureus among SSIs in China was similar to that in the US but seemed higher than those reported through the Chinese national surveillance system. Proportions of S. aureus SSIs may vary with different surgery types. Commonly seen in SSIs, MRSA tended to be highly sensitive to vancomycin and linezolid but mostly resistant to clindamycin and erythromycin.
PMCID: PMC4300093  PMID: 25602284
3.  Effects of Glucagon-Like Peptide-1 Receptor Agonists on Weight Loss in Patients with Type 2 Diabetes: A Systematic Review and Network Meta-Analysis 
Journal of Diabetes Research  2015;2015:157201.
To evaluate the effectiveness of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) on weight reduction in patients with Type 2 diabetes mellitus (Type 2 DM), a network meta-analysis was conducted. MEDLINE, EMBASE, Cochrane Library, and were searched from 1950 to October 2013. Randomized controlled trials (RCTs) involving GLP-1 RAs were included if they provided information on body weight. A total of 51 RCTs were included and 17521 participants were enrolled. The mean duration of 51 RCTs was 31 weeks. Exenatide 10 μg twice daily (EX10BID) reduced weight compared with exenatide 5 μg twice daily (EX5BID), liraglutide 0.6 mg once daily (LIR0.6QD), liraglutide—1.2 mg once daily (LIR1.2QD), and placebo treatment, with mean differences of −1.07 kg (95% CI: −2.41, −0.02), −2.38 kg (95% CI: −3.71, −1.06), −1.62 kg (95% CI: −2.79, −0.43), and −1.92 kg (95% CI: −2.61, −1.24), respectively. Reductions of weight treated with liraglutide—1.8 mg once daily (LIR1.8QD) reach statistical significance (−1.43 kg (95% CI: −2.73, −0.15)) versus LIR1.2QD and (−0.98 kg (95% CI: −1.94, −0.02)) versus placebo. Network meta-analysis found that EX10BID, LIR1.8QD, and EX2QW obtained a higher proportion of patients with weight loss than other traditional hypoglycemic agents. Our results suggest GLP-1 RAs are promising candidates for weight control in comparison with traditional hypoglycemic drugs, and EX10BID, LIR1.8QD, and EX2QW rank the top three drugs.
PMCID: PMC4320855
4.  ADAMTS-7 Exhibits Elevated Expression in Cartilage of Osteonecrosis of Femoral Head and Has a Positive Correlation with TNF-α and NF-κB P65 
Mediators of Inflammation  2015;2015:196702.
ADAMTS-7 has been reported to exaggerate cartilage degeneration and to be associated with TNF-α and NF-κB signaling pathway. In this study we compared the expression of ADAMTS-7, TNF-α, and Phospho-NF-κB in patients with femoral neck fracture (FNF) and osteonecrosis of femoral head (ONFH) at different stages. We found that expression of ADAMTS-7, TNF-α, and Phospho-NF-κB was significantly upregulated in ONFH patients' articular cartilage and related to the pathogenesis of ONFH. Thus we conclude that ADAMTS-7 level appears to be positively associated with expression of TNF-α and Phospho-NF-κB P65 in cartilage, which may imply its association with cartilage destruction of ONFH.
PMCID: PMC4310498  PMID: 25653475
5.  Extraction of Heart Rate Variability from Smartphone Photoplethysmograms 
Heart rate variability (HRV) is a useful clinical tool for autonomic function assessment and cardiovascular diseases diagnosis. It is traditionally calculated from a dedicated medical electrocardiograph (ECG). In this paper, we demonstrate that HRV can also be extracted from photoplethysmograms (PPG) obtained by the camera of a smartphone. Sixteen HRV parameters, including time-domain, frequency-domain, and nonlinear parameters, were calculated from PPG captured by a smartphone for 30 healthy subjects and were compared with those derived from ECG. The statistical results showed that 14 parameters (AVNN, SDNN, CV, RMSSD, SDSD, TP, VLF, LF, HF, LF/HF, nLF, nHF, SD1, and SD2) from PPG were highly correlated (r > 0.7, P < 0.001) with those from ECG, and 7 parameters (AVNN, TP, VLF, LF, HF, nLF, and nHF) from PPG were in good agreement with those from ECG within the acceptable limits. In addition, five different algorithms to detect the characteristic points of PPG wave were also investigated: peak point (PP), valley point (VP), maximum first derivative (M1D), maximum second derivative (M2D), and tangent intersection (TI). The results showed that M2D and TI algorithms had the best performance. These results suggest that the smartphone might be used for HRV measurement.
PMCID: PMC4309304
6.  The enhancement of radiosensitivity in human esophageal squamous cell carcinoma cells by zoledronic acid and its potential mechanism 
Cytotechnology  2013;66(1):17-25.
Esophageal squamous cell carcinoma (ESCC) has a low 5-year patient survival rate. Radiotherapy, as a preoperative or postoperative treatment of surgery, has a crucial role in improving local control and survival of ESCC. Various chemotherapeutic and biologic agents have been used as radio-sensitizers in combination with radiotherapy. Here, we demonstrate that zoledronic acid (ZOL) has a radio-sensitizing effect on ESCC cells. Exposure of ESCC cancer cells to ZOL plus radiation resulted in increased cell death through arresting the cell cycle between S and G2/M phases. ZOL appeared to inhibit proliferation, tube formation and invasion of endothelial cells. These anti-angiogenetic effects were more marked concurrently with irradiation. In addition, synergistic suppressive effects on VEGF expression were observed after combined treatment. Our data suggest that the combination of ZOL and radiation is a promising therapeutic strategy to enhance radiation therapy for ESCC patients.
PMCID: PMC3886539  PMID: 23334334
ESCC; Bisphosphonate; Radiosensitivity; Combined effect
7.  PBX3 promotes migration and invasion of colorectal cancer cells via activation of MAPK/ERK signaling pathway 
World Journal of Gastroenterology : WJG  2014;20(48):18260-18270.
AIM: To investigate the role of pre-B-cell leukemia homeobox (PBX)3 in migration and invasion of colorectal cancer (CRC) cells.
METHODS: We detected PBX3 expression in five cell lines and surgical specimens from 111 patients with CRC using real-time reverse transcription-polymerase chain reaction. We forced expression of PBX3 in low metastatic HT-29 and SW480 cells and knocked down expression of PBX3 in highly metastatic LOVO and HCT-8 cells. Wound healing and Boyden chamber assays were used to detect cell migration and invasion after altered expression of PBX3. Western blot was performed to detect the change of signaling molecule ERK1/2 following PBX3 overexpression.
RESULTS: High level of PBX3 expression was correlated with the invasive potential of CRC cells, and significantly associated with lymph node invasion (P = 0.02), distant metastasis (P = 0.04), advanced TNM stage (P = 0.03) and poor overall survival of patients (P < 0.05). Ectopic expression of PBX3 in low metastatic cells was shown to promote migration and invasion, while inhibited PBX3 expression in highly metastatic cells suppressed migration and invasion. Furthermore, upregulation of phosphorylated extracellular signal-regulated kinase (ERK)1/2 was found to be one of the targeted molecules responsible for PBX3-induced CRC cell migration and invasion.
CONCLUSION: PBX3 induces invasion and metastasis of CRC cells partially through activation of the MAPK/ERK signaling pathway.
PMCID: PMC4277963  PMID: 25561793
Pre-B-cell leukemia homeobox 3; Colorectal cancer; Cell migration; Cell invasion; Mitogen-activated protein kinase signaling pathway
8.  Minocycline ameliorates cognitive impairment induced by whole-brain irradiation: an animal study 
It has been long recognized that cranial irradiation used for the treatment of primary and metastatic brain tumor often causes neurological side-effects such as intellectual impairment, memory loss and dementia, especially in children patients. Our previous study has demonstrated that whole-brain irradiation (WBI) can cause cognitive decline in rats. Minocycline is an antibiotic that has shown neuroprotective properties in a variety of experimental models of neurological diseases. However, whether minocycline can ameliorate cognitive impairment induced by ionizing radiation (IR) has not been tested. Thus this study aimed to demonstrate the potential implication of minocycline in the treatment of WBI-induced cognitive deficits by using a rat model.
Sprague Dawley rats were cranial irradiated with electron beams delivered by a linear accelerator with a single dose of 20 Gy. Minocycline was administered via oral gavages directly into the stomach before and after irradiation. The open field test was used to assess the anxiety level of rats. The Morris water maze (MWM) was used to assess the spatial learning and memory of rats. The level of apoptosis in hippocampal neurons was measured using immunohistochemistry for caspase-3 and relative markers for mature neurons (NeuN) or for newborn neurons (Doublecortin (DCX)). Neurogenesis was determined by BrdU incorporation method.
Neither WBI nor minocycline affected the locomotor activity and anxiety level of rats. However, compared with the sham-irradiated controls, WBI caused a significant loss of learning and memory manifest as longer latency to reach the hidden platform in the MWM task. Minocycline intervention significantly improved the memory retention of irradiated rats. Although minocycline did not rescue neurogenesis deficit caused by WBI 2 months post-IR, it did significantly decreased WBI-induced apoptosis in the DCX positive neurons, thereby resulting in less newborn neuron depletion 12 h after irradiation.
Minocycline significantly inhibits WBI-induced neuron apoptosis, leading to less newborn neurons loss shortly after irradiation. In the long run, minocycline improves the cognitive performance of rats post WBI. The results indicate a potential clinical implication of minocycline as an effective adjunct in radiotherapy for brain tumor patients.
PMCID: PMC4271325  PMID: 25498371
Whole-brain irradiation; Cognitive deficit; Minocycline; Newborn neuron; Apoptosis; Neurogenesis
9.  Risk Evaluation of Bogie System Based on Extension Theory and Entropy Weight Method 
A bogie system is the key equipment of railway vehicles. Rigorous practical evaluation of bogies is still a challenge. Presently, there is overreliance on part-specific experiments in practice. In the present work, a risk evaluation index system of a bogie system has been established based on the inspection data and experts' evaluation. Then, considering quantitative and qualitative aspects, the risk state of a bogie system has been evaluated using an extension theory and an entropy weight method. Finally, the method has been used to assess the bogie system of four different samples. Results show that this method can assess the risk state of a bogie system exactly.
PMCID: PMC4276359  PMID: 25574159
10.  Effect of ambroxol on the concentration of cefotaxime in the bronchoalveolar lavage fluid of rats with pulmonary fibrosis 
This study aimed to investigate the effect of ambroxol on the concentration of cefotaxime in the bronchioalveolar lavage fluid of rats with bleomycin-induced pulmonary fibrosis. A total of 54 Wistar male rats were randomly divided into three groups, namely the normal control group, model group and ambroxol group. On experimental day 0, the rats were intratracheally instilled with bleomycin (5 mg/kg body weight) or sterile saline. The rats in the ambroxol group were then treated with ambroxol (35 mg/kg/day) intraperitoneally. On days 7, 14, 28 after instillation, six rats from each group were sacrificed, bronchial alveolar fluids were recovered and the lungs were collected for histopathological examination following the injection of cefotaxime (600 mg/kg) intravenously. The concentration of cefotaxime in the bronchial alveolar fluids was assayed by a liquid chromatography-mass spectrometry method. On day 7, the concentration of cefotaxime in the bronchial alveolar fluid of the ambroxol group was lower than that of the model group. On day 14, the concentration of cefotaxime in the bronchial alveolar fluids of the ambroxol group was higher than that of the model group, and the difference between these groups was significant statistically (P<0.001). On day 28, the concentration of cefotaxime in the bronchial alveolar fluids of the ambroxol group decreased sharply, and was lower than that of the model group (P=0.126). These results indicate that ambroxol increased the concentration of cefotaxime in the bronchial alveolar fluids at the primary fibrosis stage.
PMCID: PMC4280944  PMID: 25574230
pulmonary fibrosis; ambroxol; cefotaxime
11.  Oncogenic induction of cellular high CpG methylation by Epstein-Barr virus in malignant epithelial cells 
Chinese Journal of Cancer  2014;33(12):604-608.
Epstein-Barr virus (EBV) is a well-known human herpesvirus associated with virtually all nasopharyngeal carcinoma (NPC) and ∼10% of gastric cancer (GC) worldwide. Increasing evidence shows that acquired genetic and epigenetic alterations lead to the initiation and progression of NPC and GC. However, even deep whole exome sequencing studies showed a relatively low frequency of gene mutations in NPC and EBV-associated GC (EBVaGC), suggesting a predominant role of epigenetic abnormities, especially promoter CpG methylation, in the pathogenesis of NPC and EBVaGC. High frequencies of promoter methylation of tumor suppressor genes (TSGs) have been frequently reported in NPC and EBVaGC, with several EBV-induced methylated TSGs identified. Further characterization of the epigenomes (genome-wide CpG methylation profile—methylome) of NPC and EBVaGC shows that these EBV-associated tumors display a unique high CpG methylation epigenotype with more extensive gene methylation accumulation, indicating that EBV acts as a direct epigenetic driver for these cancers. Mechanistically, oncogenic modulation of cellular CpG methylation machinery, such as DNA methyltransferases (DNMTs), by EBV-encoded viral proteins accounts for the EBV-induced high CpG methylation epigenotype in NPC and EBVaGC. Thus, uncovering the EBV-associated unique epigenotype of NPC and EBVaGC would provide new insight into the molecular pathogenesis of these unique EBV-associated tumors and further help to develop pharmacologic strategies targeting cellular methylation machinery in these malignancies.
PMCID: PMC4308656  PMID: 25322866
Epstein-Barr virus; CpG methylation; DNA methyltransferase; tumor suppressor gene; naso-pharyngeal carcinoma; gastric cancer
12.  Systematic Analysis of the Multiple Bioactivities of Green Tea through a Network Pharmacology Approach 
During the past decades, a number of studies have demonstrated multiple beneficial health effects of green tea. Polyphenolics are the most biologically active components of green tea. Many targets can be targeted or affected by polyphenolics. In this study, we excavated all of the targets of green tea polyphenolics (GTPs) though literature mining and target calculation and analyzed the multiple pharmacology actions of green tea comprehensively through a network pharmacology approach. In the end, a total of 200 Homo sapiens targets were identified for fifteen GTPs. These targets were classified into six groups according to their related disease, which included cancer, diabetes, neurodegenerative disease, cardiovascular disease, muscular disease, and inflammation. Moreover, these targets mapped into 143 KEGG pathways, 26 of which were more enriched, as determined though pathway enrichment analysis and target-pathway network analysis. Among the identified pathways, 20 pathways were selected for analyzing the mechanisms of green tea in these diseases. Overall, this study systematically illustrated the mechanisms of the pleiotropic activity of green tea by analyzing the corresponding “drug-target-pathway-disease” interaction network.
PMCID: PMC4267163  PMID: 25525446
13.  Lipid-Coated Cisplatin Nanoparticles Induce Neighboring Effect and Exhibit Enhanced Anticancer Efficacy 
ACS nano  2013;7(11):9896-9904.
Encapsulation of cisplatin (CDDP) into nanoparticles (NPs) with high drug loading and encapsulation efficiency has been difficult due to the poor solubility of CDDP. However, this barrier has been overcome with a reverse microemulsion method appropriating CDDP’s poor solubility to our advantage promoting the synthesis of a pure cisplatin nanoparticle with a high drug loading capacity (approximately 80.8wt%). Actively targeted CDDP NPs exhibited significant accumulation in human A375M melanoma tumor cells in vivo. In addition, CDDP NPs achieved potent anti-tumor efficacy through the neighboring effect at a dose of 1 mg/kg when injected weekly via IV without inducing nephrotoxicity. The neighboring effect regards an observation made in vivo when the tumor cells that took up CDDP NPs released active drug following apoptosis. Via diffusion, surrounding cells that were previously unaffected showed intake of the released drug and their apoptosis soon followed. This observation was also made in vitro when A375M melanoma tumor cells incubated with CDDP NPs exhibited release of active drug and induced apoptosis on untreated neighboring cells. However, the neighboring effect was unique to rapidly proliferating tumor cells. Liver functional parameters and H&E staining of liver tissue in vivo failed to detect any difference between CDDP NP treated and control groups in terms of tissue health. By simultaneously promoting an increase in cytotoxicity and a lesser degree of side effects over free CDDP, CDDP NPs show great therapeutic potential with lower doses of drug while enhancing anti-cancer effectiveness.
PMCID: PMC3906679  PMID: 24083505
Cisplatin; Chemotherapy; Nanomedicine; Drug delivery; Neighboring effect
14.  A numerical study of the effect of varied blood pressure on the stability of carotid atherosclerotic plaque 
Blood pressure (BP) is associated with early atherosclerosis and plaque rupture because the BP variability can significantly affect the blood flow velocity and shear stress over the plaque. However, the mechanical response of BP variability to the plaque remains unclear. Therefore, we investigated the correlation between different maximum systolic blood pressure (SBP) and the stress distribution on plaque, as well as the stress over the plaque and blood velocity around the plaque using different BP variations, which are the BP variability in different phases during one cardiac cycle and beat-to-beat BP variability.
We established a two-dimensional artery model with stenosis at the degree of 62.5%. Eight combinations of pulsatile pressure gradients between the inflow and outflow were implemented at the model. Three levels of fibrous cap thickness were taken into consideration to investigate the additional effect on the BP variability. Wall shear stress and stress/strain distribution over the plaque were derived as well as the oscillation shear index (OSI) to analyze the impact of the changing rate of BP.
The stresses at diastole were 2.5% ± 1.8% lower than that at systole under the same pressure drop during one cycle. It was also found that elevated SBP might cause the immediate increment of stress in the present cycle (292% ± 72.3%), but slight reduction in the successive cycle (0.48% ± 0.4%).
The stress/strain distribution over the plaque is sensitive to the BP variability during one cardiac cycle, and the beat-to-beat BP variability could cause considerable impact on the progression of atherosclerosis in long-term.
PMCID: PMC4277844  PMID: 25413300
Atherosclerotic plaque vulnerability; Stress distribution; Blood pressure; Computational mechanical analysis
15.  Automated Detection Framework of the Calcified Plaque with Acoustic Shadowing in IVUS Images 
PLoS ONE  2014;9(11):e109997.
Intravascular Ultrasound (IVUS) is one ultrasonic imaging technology to acquire vascular cross-sectional images for the visualization of the inner vessel structure. This technique has been widely used for the diagnosis and treatment of coronary artery diseases. The detection of the calcified plaque with acoustic shadowing in IVUS images plays a vital role in the quantitative analysis of atheromatous plaques. The conventional method of the calcium detection is manual drawing by the doctors. However, it is very time-consuming, and with high inter-observer and intra-observer variability between different doctors. Therefore, the computer-aided detection of the calcified plaque is highly desired. In this paper, an automated method is proposed to detect the calcified plaque with acoustic shadowing in IVUS images by the Rayleigh mixture model, the Markov random field, the graph searching method and the prior knowledge about the calcified plaque. The performance of our method was evaluated over 996 in-vivo IVUS images acquired from eight patients, and the detected calcified plaques are compared with manually detected calcified plaques by one cardiology doctor. The experimental results are quantitatively analyzed separately by three evaluation methods, the test of the sensitivity and specificity, the linear regression and the Bland-Altman analysis. The first method is used to evaluate the ability to distinguish between IVUS images with and without the calcified plaque, and the latter two methods can respectively measure the correlation and the agreement between our results and manual drawing results for locating the calcified plaque in the IVUS image. High sensitivity (94.68%) and specificity (95.82%), good correlation and agreement (>96.82% results fall within the 95% confidence interval in the Student t-test) demonstrate the effectiveness of the proposed method in the detection of the calcified plaque with acoustic shadowing in IVUS images.
PMCID: PMC4220935  PMID: 25372784
16.  Combinational delivery of c-Myc siRNA and nucleoside analogues in a single, synthetic nanocarrier for targeted cancer therapy 
Biomaterials  2013;34(33):8459-8468.
The treatment of aggressive non-small-cell lung cancer (NSCLC) depends on the creation of new therapeutic regimens in clinical settings. In this study, we developed a Lipid/Calcium/Phosphate (LCP) nanoparticle that combines chemotherapy with gene therapy. By encapsulating a chemodrug, gemcitabine monophosphate (GMP), and siRNA specific to the undruggable c-Myc oncogene (c-Myc siRNA) into a single nanosized vesicle and systemically administering them to nude mice, we achieved potent anti-tumor activity in both subcutaneous and orthotopic models of NSCLC. The improvements in therapeutic response over either c-Myc siRNA or GMP therapy alone, were demonstrated by the ability to effectively induce the apoptosis of tumor cells and the significant reduction of proliferation of tumor cells. The combination therapy led to dramatic inhibition of tumor growth, with little in vivo toxicity. Additionally, the current studies demonstrated the possibility of incorporating both nucleic acid molecules and phosphorylated small molecule drugs into the inner core of a single nanoparticle formulation. Co-encapsulation of an oncogene-modulating siRNA and a chemotherapeutic agent will allow simultaneous interruption of diverse anti-cancer pathways, leading to increased therapeutic efficacy and reduced toxicities.
PMCID: PMC3926217  PMID: 23932296
c-Myc siRNA; Gemcitabine monophosphate; Calcium phosphate nanoparticle; Apoptosis; Proliferation
17.  rFN/Cad-11-Modified Collagen Type II Biomimetic Interface Promotes the Adhesion and Chondrogenic Differentiation of Mesenchymal Stem Cells 
Tissue Engineering. Part A  2013;19(21-22):2464-2477.
Properties of the cell-material interface are determining factors in the successful function of cells for cartilage tissue engineering. Currently, cell adhesion is commonly promoted through the use of polypeptides; however, due to their lack of complementary or modulatory domains, polypeptides must be modified to improve their ability to promote adhesion. In this study, we utilized the principle of matrix-based biomimetic modification and a recombinant protein, which spans fragments 7–10 of fibronectin module III (heterophilic motif ) and extracellular domains 1–2 of cadherin-11 (rFN/Cad-11) (homophilic motif ), to modify the interface of collagen type II (Col II) sponges. We showed that the designed material was able to stimulate cell proliferation and promote better chondrogenic differentiation of rabbit mesenchymal stem cells (MSCs) in vitro than both the FN modified surfaces and the negative control. Further, the Col II/rFN/Cad-11-MSCs composite stimulated cartilage formation in vivo; the chondrogenic effect of Col II alone was much less significant. These results suggested that the rFN/Cad-11-modified collagen type II biomimetic interface has dual biological functions of promoting adhesion and stimulating chondrogenic differentiation. This substance, thus, may serve as an ideal scaffold material for cartilage tissue engineering, enhancing repair of injured cartilage in vivo.
PMCID: PMC3807536  PMID: 23919505
18.  Conserved Dopamine Neurotrophic Factor-Transduced Mesenchymal Stem Cells Promote Axon Regeneration and Functional Recovery of Injured Sciatic Nerve 
PLoS ONE  2014;9(10):e110993.
Peripheral nerve injury (PNI) is a common disease that often results in axonal degeneration and the loss of neurons, ultimately leading to limited nerve regeneration and severe functional impairment. Currently, there are no effective treatments for PNI. In the present study, we transduced conserved dopamine neurotrophic factor (CDNF) into mesenchymal stem cells (MSCs) in collagen tubes to investigate their regenerative effects on rat peripheral nerves in an in vivo transection model. Scanning electron microscopy of the collagen tubes demonstrated their ability to be resorbed in vivo. We observed notable overexpression of the CDNF protein in the distal sciatic nerve after application of CDNF-MSCs. Quantitative analysis of neurofilament 200 (NF200) and S100 immunohistochemistry showed significant enhancement of axonal and Schwann cell regeneration in the group receiving CDNF-MSCs (CDNF-MSCs group) compared with the control groups. Myelination thickness, axon diameter and the axon-to fiber diameter ratio (G-ratio) were significantly higher in the CDNF-MSCs group at 8 and 12 weeks after nerve transection surgery. After surgery, the sciatic functional index, target muscle weight, wet weight ratio of gastrocnemius muscle and horseradish peroxidase (HRP) tracing demonstrated functional recovery. Light and electron microscopy confirmed successful regeneration of the sciatic nerve. The greater numbers of HRP-labeled neuron cell bodies and increased sciatic nerve index values (SFI) in the CDNF-MSCs group suggest that CDNF exerts neuroprotective effects in vivo. We also observed higher target muscle weights and a significant improvement in muscle atrophism in the CDNF-MSCs group. Collectively, these findings indicate that CDNF gene therapy delivered by MSCs is capable of promoting nerve regeneration and functional recovery, likely because of the significant neuroprotective and neurotrophic effects of CDNF and the superior environment offered by MSCs and collagen tubes.
PMCID: PMC4208796  PMID: 25343619
19.  Irisin Promotes Human Umbilical Vein Endothelial Cell Proliferation through the ERK Signaling Pathway and Partly Suppresses High Glucose-Induced Apoptosis 
PLoS ONE  2014;9(10):e110273.
Irisin is a newly discovered myokine that links exercise with metabolic homeostasis. It is involved in modest weight loss and improves glucose intolerance. However, the direct effects and mechanisms of irisin on vascular endothelial cells (ECs) are not fully understood. In the current study, we demonstrated that irisin promoted Human Umbilical Vein Endothelial Cell (HUVEC) proliferation. It was further demonstrated that this pro-proliferation effect was mediated by irisin-induced activation of extracellular signal–related kinase (ERK) signaling pathways. Inhibition of ERK signaling with U0126 decreased the pro-proliferation effect of irisin on HUVECs. It was also demonstrated that irisin reduced high glucose-induced apoptosis by up-regulating Bcl-2 expression and down-regulating Bax, Caspase-9 and Caspase-3 expression. In summary, these results suggested that irisin plays a novel role in sustaining endothelial homeostasis by promoting HUVEC proliferation via the ERK signaling pathway and protects the cell from high glucose-induced apoptosis by regulating Bcl-2,Bax and Caspase expression.
PMCID: PMC4206299  PMID: 25338001
20.  Akebia trifoliate (Thunb.) Koidz Seed Extract Inhibits the Proliferation of Human Hepatocellular Carcinoma Cell Lines via Inducing Endoplasmic Reticulum Stress 
Akebia Fructus has long been used for hepatocellular carcinoma (HCC) in China, while the molecular mechanism remains obscure. Our recent work found that Akebia trifoliate (Thunb.) Koidz seed extract (ATSE) suppressed proliferation and induced endoplasmic reticulum (ER) stress in SMMC-7721. The present study aimed to throw more light on the mechanism. ER stress occurred after ATSE treatment in HepG2, HuH7, and SMMC-7721 cells, manifested as ER expansion, and SMMC-7721 was the most sensitive kind in terms of morphology. Cell viability assay showed that ATSE significantly inhibited cells proliferation. Flow cytometry analysis indicated that ATSE leads to an upward tendency of G0/G1 phase and a reduced trend of the continuous peak after G2/M phase in HepG2; ATSE promoted apoptosis in HuH7 and a notable reduction in G0/G1 phase; ATSE does not quite influence cell cycles of SMMC-7721. Western blot analysis showed an increased trend of the chosen ER stress-related proteins after different treatments but nonsignificantly; only HYOU1 and GRP78 were decreased notably by ATSE in HuH7. Affymetrix array indicated that lots of ER stress-related genes' expressions were significantly altered, and downward is the main trend. These results suggest that ATSE have anticancer potency in HCC cells via partly inducing ER stress.
PMCID: PMC4217368  PMID: 25389441
21.  Enrichment of statistical power for genome-wide association studies 
BMC Biology  2014;12(1):73.
The inheritance of most human diseases and agriculturally important traits is controlled by many genes with small effects. Identifying these genes, while simultaneously controlling false positives, is challenging. Among available statistical methods, the mixed linear model (MLM) has been the most flexible and powerful for controlling population structure and individual unequal relatedness (kinship), the two common causes of spurious associations. The introduction of the compressed MLM (CMLM) method provided additional opportunities for optimization by adding two new model parameters: grouping algorithms and number of groups.
This study introduces another model parameter to develop an enriched CMLM (ECMLM). The parameter involves algorithms to define kinship between groups (that is, kinship algorithms). The ECMLM calculates kinship using several different algorithms and then chooses the best combination between kinship algorithms and grouping algorithms.
Simulations show that the ECMLM increases statistical power. In some cases, the magnitude of power gained by using ECMLM instead of CMLM is larger than the improvement found by using CMLM instead of MLM.
Electronic supplementary material
The online version of this article (doi:10.1186/s12915-014-0073-5) contains supplementary material, which is available to authorized users.
PMCID: PMC4210555  PMID: 25322753
Genome wide association study; population structure; kinship; mixed model; cluster analysis
22.  Stability profiling of anti-malarial drug piperaquine phosphate and impurities by HPLC-UV, TOF-MS, ESI-MS and NMR 
Malaria Journal  2014;13(1):401.
Piperaquine, 1,3-bis-[4-(7-chloroquinolyl-4)-piperazinyl-1]-propane, is an anti-malarial compound belonging to the 4-aminoquinolines, which has received renewed interest in treatment of drug resistant falciparum malaria in artemisinin-based combination therapy with dihydroartemisinin. The impurity profile of this drug product is paid an ever-increasing attention. However, there were few published studies of the complete characterization of related products or impurities in piperaquine phosphate bulk and forced degradation samples.
The impurities in piperaquine phosphate bulk drug substance were detected by a newly developed gradient phase HPLC method and identified by TOF-MS and ESI-MS. The structures of impurities were confirmed by NMR. Forced degradation studies were also performed for the stability of piperaquine phosphate bulk drug samples and the specificity of the newly developed HPLC method. In silico toxicological predictions for these piperaquine phosphate related impurities were made by Toxtree® and Derek®.
Twelve impurities (imp-1–12) were detected and identified, of which eight impurities (imp-1, 2, 4, 6–10) were first proposed as new related substances. Based on TOF-MS/ESI-MS and NMR analysis, the structures of imp-2, 6 and 12 were characterized by their synthesis and preparation. The possible mechanisms for the formation of impurities were also discussed. These piperaquine phosphate related impurities were predicted to have a toxicity risk by Toxtree® and Derek®.
From forced degradation and bulk samples of piperaquine phosphate, twelve compounds were detected and identified to be piperaquine phosphate related impurities. Two of the new piperaquine phosphate related substances, imp-2 and imp-6, were identified and characterized as 4-hydroxy-7-chloro-quinoline and a piperaquine oxygenate with a piperazine ring of nitrogen oxide in bulk drug and oxidation sample, respectively. The MS data of imp-1, 2, 4, 6–10 were first reported. The in-silico toxicological prediction showed a toxicity risk for piperaquine related impurities by Toxtree® and Derek®.
Electronic supplementary material
The online version of this article (doi:10.1186/1475-2875-13-401) contains supplementary material, which is available to authorized users.
PMCID: PMC4210591  PMID: 25311421
Anti-malarial; Piperaquine; Related impurities; Stability profile; RP-HPLC; TOF-MS; ESI-MS; NMR
23.  JAK2/STAT3 Inhibition Attenuates Noise-Induced Hearing Loss 
PLoS ONE  2014;9(10):e108276.
Signal transducers and activators of transcription 3 (STAT3) is a stress responsive transcription factor that plays a key role in oxidative stress-mediated tissue injury. As reactive oxygen species (ROS) are a known source of damage to tissues of the inner ear following loud sound exposure, we examined the role of the Janus kinase 2 (JAK2)/STAT3 signaling pathway in noise induce hearing loss using the pathway specific inhibitor, JSI-124. Mice were exposed to a moderately damaging level of loud sound revealing the phosphorylation of STAT3 tyrosine 705 residues and nuclear localization in many cell types in the inner ear including the marginal cells of the stria vascularis, type II, III, and IV fibrocytes, spiral ganglion cells, and in the inner hair cells. Treatment of the mice with the JAK2/STAT3 inhibitor before noise exposure reduced levels of phosphorylated STAT3 Y705. We performed auditory brain stem response and distortion product otoacoustic emission measurements and found increased recovery of hearing sensitivity at two weeks after noise exposure with JAK2/STAT3 inhibition. Performance of cytocochleograms revealed improved outer hair cell survival in JSI-124 treated mice relative to control. Finally, JAK2/STAT3 inhibition reduced levels of ROS detected in outer hair cells at two hours post noise exposure. Together, these findings demonstrate that inhibiting the JAK2/STAT3 signaling pathway is protective against noise-induced cochlear tissue damage and loss of hearing sensitivity.
PMCID: PMC4183445  PMID: 25275304
24.  Developmental outcomes of children with congenital diaphragmatic hernia: a multicenter prospective study 
Journal of pediatric surgery  2013;48(10):10.1016/j.jpedsurg.2013.02.041.
To determine developmental outcomes and associated factors in patients with congenital diaphragmatic hernia (CDH) at two years of age.
This is a multicenter prospective study of a CDH birth cohort. Clinical and socioeconomic data were collected. Bayley Scales of Infant Development (BSID-III) and Vineland Adaptive Behavior Scales (VABS-II) were performed at two years of age.
BSID-III and VABS-II assessments were completed on 48 and 49 children, respectively. The BSID-III mean cognitive, language, and motor scores were significantly below the norm mean with average scores of 93 +/− 15, 95 +/−16, and 95 +/− 11. Ten percent (5/47) scored more than two standard deviations below the norm on one or more domains. VABS-II scores were similar to BSID-III scores with mean communication, daily living skills, social, motor, adaptive behavior scores of 97 +/−14, 94+/−16, 93 +/− 13, 97+/− 10, and 94 +/− 14. For the BSID-III, supplemental oxygen at 28 days, a prenatal diagnosis, need for extracorporeal membrane oxygenation (ECMO) and exclusive tube feeds at time of discharge were associated with lower scores. At two years of age, history of hospital readmission and need for tube feeds were associated with lower scores. Lower socioeconomic status correlated with lower developmental scores when adjusted for significant health factors.
CDH patients on average have lower developmental scores at two years of age compared to the norm. A need for ECMO, oxygen at 28 days of life, ongoing health issues and lower socioeconomic status are factors associated with developmental delays.
PMCID: PMC3884579  PMID: 24094947
congenital diaphragmatic hernia; neurodevelopment; Hollingshead; socioeconomic status
25.  Turning an antiviral into an anticancer drug: Nanoparticle delivery of acyclovir monophosphate 
Anti-herpes simplex virus (HSV) drug acyclovir (ACV) is phosphorylated by the viral thymidine kinase (TK), but not the cellular TK. Phosphorylated ACV inhibits cellular DNA synthesis and kills the infected cells. We hypothesize that ACV monophosphate (ACVP), which is an activated metabolite of ACV, should be efficient in killing cells independent of HSV-TK. If so, ACVP should be a cytotoxic agent if properly delivered to the cancer cells. The Lipid/Calcium/Phosphate (LCP) nanoparticles (NPs) with a membrane/core structure were used to encapsulate ACVP to facilitate the targeted delivery of ACVP to the tumor. The LCP NPs showed entrapment efficiency of ~69%, the nano-scaled particle size and positive zeta potential. Moreover, ACVP-loaded LCP NPs (A-LCP NPs) exhibited concentration-dependent cytotoxicity against H460 cells and increased S-phase arrest. More importantly, a significant reduction of the tumor volume over 4 days following administration (p<0.05~0.005) of A-LCP NPs, suggests excellent in vivo efficacy. Whereas, two free drugs (ACV and ACVP) and blank LCP NPs showed little or no therapeutic effect. It was also found that the high efficacy of A-LCP NPs was associated with the ability to induce dramatic apoptosis of the tumor cells, as well as significantly inhibit tumor cell proliferation and cell cycle progression. In conclusion, with the help of LCP NPs, monophosphorylation modification of ACV can successfully modify an HSV-TK-dependent antiviral drug into an anti-tumor drug.
PMCID: PMC3742590  PMID: 23791977
Acyclovir monophosphate; Calcium phosphate; Nanoparticles; tumor therapy

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