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1.  “Mouse Clone Model” for evaluating the immunogenicity and tumorigenicity of pluripotent stem cells 
To investigate the immune-rejection and tumor-formation potentials of induced pluripotent stem cells and other stem cells, we devised a model—designated the “Mouse Clone Model”—which combined the theory of somatic animal cloning, tetraploid complementation, and induced pluripotent stem cells to demonstrate the applicability of stem cells for transplantation therapy.
PMCID: PMC4684929  PMID: 26687081
2.  Characterization of Polyethylene-Graft-Sulfonated Polyarylsulfone Proton Exchange Membranes for Direct Methanol Fuel Cell Applications 
Membranes  2015;5(4):875-887.
This paper examines polymer film morphology and several important properties of polyethylene-graft-sulfonated polyarylene ether sulfone (PE-g-s-PAES) proton exchange membranes (PEMs) for direct methanol fuel cell applications. Due to the extreme surface energy differences between a semi-crystalline and hydrophobic PE backbone and several amorphous and hydrophilic s-PAES side chains, the PE-g-s-PAES membrane self-assembles into a unique morphology, with many proton conductive s-PAES channels embedded in the stable and tough PE matrix and a thin hydrophobic PE layer spontaneously formed on the membrane surfaces. In the bulk, these membranes show good mechanical properties (tensile strength >30 MPa, Young’s modulus >1400 MPa) and low water swelling (λ < 15) even with high IEC >3 mmol/g in the s-PAES domains. On the surface, the thin hydrophobic and semi-crystalline PE layer shows some unusual barrier (protective) properties. In addition to exhibiting higher through-plane conductivity (up to 160 mS/cm) than in-plane conductivity, the PE surface layer minimizes methanol cross-over from anode to cathode with reduced fuel loss, and stops the HO• and HO2• radicals, originally formed at the anode, entering into PEM matrix. Evidently, the thin PE surface layer provides a highly desirable protecting layer for PEMs to reduce fuel loss and increase chemical stability. Overall, the newly developed PE-g-s-PAES membranes offer a desirable set of PEM properties, including conductivity, selectivity, mechanical strength, stability, and cost-effectiveness for direct methanol fuel cell applications.
PMCID: PMC4704017  PMID: 26690232
polyethylene; direct methanol fuel cells; surface hydrophobicity; electrochemical stability; methanol permeability
3.  Anti-Ganglioside Antibodies Induce Nodal and Axonal Injury via Fcγ Receptor-Mediated Inflammation 
The Journal of Neuroscience  2015;35(17):6770-6785.
Guillain-Barré syndrome (GBS) is a postinfectious autoimmune neuropathy and anti-ganglioside antibodies (Abs) are strongly associated with this disorder. Several studies have implied that specific anti-ganglioside Abs induce neuropathy in patients with axonal forms of GBS. To study the mechanisms of anti-ganglioside Abs-induced neuropathy, we established a new passive transfer mouse model by L5 spinal nerve transection (L5SNT; modified Chung's model) and systemic administration of anti-ganglioside Abs. L5SNT causes degeneration of a small proportion of fibers that constitute sciatic nerve and its branches, but importantly breaks the blood–nerve barrier, which allows access to circulating Abs and inflammatory cells. Our studies indicate that, in this mouse model, anti-ganglioside Abs induce sequential nodal and axonal injury of intact myelinated nerve fibers, recapitulating pathologic features of human disease. Notably, our results showed that immune complex formation and the activating Fc gamma receptors (FcγRs) were involved in the anti-ganglioside Abs-mediated nodal and axonal injury in this model. These studies provide new evidence that the activating FcγRs-mediated inflammation plays a critical role in anti-ganglioside Abs-induced neuropathy (injury to intact nerve fibers) in GBS.
PMCID: PMC4412896  PMID: 25926454
anti-ganglioside antibody; blood–nerve barrier; Fc gamma receptors; Guillain-Barré syndrome; macrophage; nodal and axonal injury
4.  An Ensemble Learning Based Framework for Traditional Chinese Medicine Data Analysis with ICD-10 Labels 
The Scientific World Journal  2015;2015:507925.
Objective. This study aims to establish a model to analyze clinical experience of TCM veteran doctors. We propose an ensemble learning based framework to analyze clinical records with ICD-10 labels information for effective diagnosis and acupoints recommendation. Methods. We propose an ensemble learning framework for the analysis task. A set of base learners composed of decision tree (DT) and support vector machine (SVM) are trained by bootstrapping the training dataset. The base learners are sorted by accuracy and diversity through nondominated sort (NDS) algorithm and combined through a deep ensemble learning strategy. Results. We evaluate the proposed method with comparison to two currently successful methods on a clinical diagnosis dataset with manually labeled ICD-10 information. ICD-10 label annotation and acupoints recommendation are evaluated for three methods. The proposed method achieves an accuracy rate of 88.2%  ±  2.8% measured by zero-one loss for the first evaluation session and 79.6%  ±  3.6% measured by Hamming loss, which are superior to the other two methods. Conclusion. The proposed ensemble model can effectively model the implied knowledge and experience in historic clinical data records. The computational cost of training a set of base learners is relatively low.
PMCID: PMC4609520  PMID: 26504897
5.  Impaired Spatial Learning Memory after Isoflurane Anesthesia or Appendectomy in Aged Mice is Associated with Microglia Activation 
Journal of Cell Death  2015;8:9-19.
Postoperative cognitive dysfunction (POCD) has been one of the most common problems in elderly patients following surgery. But the specific mechanism of POCD is still not clear. To further understand the reason of these postoperative behavioral deficits, we evaluated the spatial learning memory of both adult (3 months) and aged (18 months) male mice, 3 or 28 days after isoflurane (Iso) exposure for two hours or appendectomy (App). Hippocampal microglia activation and IL-1β, TNF-α, and IFN-γ expression were also evaluated at day 3, day 14 and day 28 after Iso exposure or appendectomy. Results showed that spatial learning memory of aged, but not adult, mice was impaired after Iso exposure or appendectomy, accompanied with more hippocampal microglia activation and IL-1β, TNF-α, and IFN-γ overexpression. These findings suggest that the cognitive deficits of elderly patients who have undergone surgeries are quite possibly caused by hippocampal microglia overactivation and the subsequent inflammation.
PMCID: PMC4560456  PMID: 26380557
postoperative cognitive dysfunction; microglia; surgery; isoflurane
6.  Superovulation does not affect the endocrine activity nor increase susceptibility to carcinogenesis of uterine and mammary glands of female offspring in mice 
To evaluate the dual effects of superovulation on the endocrine activity and susceptibility to carcinogenesis of uterine and mammary glands of female offspring in mice
The mice were superovaluted. The relative uterine weight, ERα protein expression, and endocrine activity of female offspring (F1 generation and F2 generation) were measured. Furthermore, proliferative lesion of uterine and mammary glands of female offspring (F1 generation and F2 generation) was assessed by histopathologic examinations.
There were no significant differences in relative uterine weight, ERα protein expression, incidence of proliferative lesion in mammary glands, and incidence of atypical hyperplasia, adenocarcinoma, and squamous metaplasia in uterine among the offspring (F1 generation and F2 generation) in each group. Likewise, there were no significant intergroup differences in the serum levels of sex related hormones.
No significant alterations were found in the endocrine activity and susceptibility to carcinogenesis of uterine and mammary glands of female offspring in mice produced by superovaluted oocytes compared with those of naturally conceived offspring.
PMCID: PMC4156948  PMID: 25106936
Superovulation; Female; Offspring; Endocrine activity; Carcinogenesis
7.  Astragalus on the anti-fatigue effect in hypoxic mice 
Objective: Astragalus is a traditional Chinese medicine to improve the function of the body. The purpose of this study is to investigate the effect of astragalus on improvement of anti-fatigue capacity in mice under simulated plateau environment. Methods: Male Kunming mice were randomly divided into the following groups: the control group, astragalus treatment groups in low dosage (LD) (1.0 g/kg·d), mid dosage (MD) (3.0 g/kg·d), and high dosage (HD) (30 g/kg·d). The control group were fed under normoxia environment, and hypoxic mice were fed at a stimulated elevation of 5000 meters. After continuous intragastric administration for 10 days, exhaustive swimming experiment was conducted in the anoxic environment. The swimming time, glucose and lactic acid concentration in blood, glycogen contents in liver, SOD and MDA were determined. Results: Compared with the control group, the swimming time of each astragalus treated group was evidently prolonged (P < 0.05), and the area under the blood lactic acid curve was significantly decreased (P < 0.05). In the high and middle dose of astragalus group, liver glycogen was obviously increased. After exhausted swimming, glycogen contents in blood and SOD were significantly increased, while MDA was evidently reduced (P < 0.05). Conclusion: Astragalus can alleviate physical fatigue in mice under simulated plateau environment. It has an obvious anti-fatigue effect and it’s worthy of further study.
PMCID: PMC4613048  PMID: 26550363
Astragalus; anti-fatigue; plateau; mice
8.  Subtypes and Prognosis of Guillain-Barré Syndrome in Southwest China 
PLoS ONE  2015;10(7):e0133520.
The proportion of different subtypes of Guillain-Barré syndrome (GBS) and their prognosis varied significantly among different regions. This study attempts to investigate the clinical subtypes and outcome of GBS in southwest China. Patients with GBS admitted to The First Affiliated Hospital of Chongqing Medical University from January 2006 to March 2013 were included in our study. Patients were classified into acute inflammatory demyelinating polyneuropathy (AIDP) group, acute motor axonal neuropathy (AMAN) group, Miller-Fisher syndrome (MFS) group, cranial nerve variants(CNV), Bickerstaff's brainstem encephalitis overlaps with GBS (BBE-GBS) group and unclassifiable group based on clinical features and electrophysiological findings. Hughes function grade score (HFGS) was used to assess the prognosis at 3 and 6 months. The prognosis of different subtypes and outcome predictors were analyzed. The most common subtype of GBS was AIDP (57%), followed by AMAN (22%) and MFS (7%). The prognosis of AMAN and BBE-GBS is similar at 3 month(P = 0.0704)and 6 month (P = 0.1614) follow-up. The prognosis of AMAN group was poorer than that of AIDP group at 3 month and 6 month follow-up (P<0.001). Outcome of MFS group and that of CNV group at 6 months were both good(Hughes≤1). Hughes≥3(P<0.0001,OR = 6.650,95%CI = 2.865 to 15.023))and dysautonomia (P = 0.043,OR = 2.820,95%CI = 1.031 to 7.715)) were associated with poor outcome at 6 month follow-up. AIDP is the most common subtype of GBS. Prognosis of AMAN group and BBE-GBS group is poorer than that of AIDP group at 3 month and 6 month follow-up. Hughes≥3 at nadir and dysautonomia are predictors of poor prognosis at 6 month follow-up.
PMCID: PMC4511520  PMID: 26200903
9.  Intraventricular Hemorrhage and Early Hematoma Expansion in Patients with Intracerebral Hemorrhage 
Scientific Reports  2015;5:11357.
Intraventricular hemorrhage is associated with poor functional outcomes in patients with intracerebral hemorrhage (ICH). We aimed to investigate the association between intraventricular hemorrhage and early hematoma expansion in patients with ICH. Patients with ICH who underwent a baseline CT scan within six hours after onset of symptoms were included. The follow-up CT scan was performed within 24 hours after the baseline CT scan. Univariate and multivariable logistic regression were used to assess the relationship between presence of intraventricular hemorrhage and early hematoma expansion. A total of 160 patients were included in the study. Significant hematoma growth was observed in 52 (32.5%) patients presenting within six hours after onset of symptoms. Intraventricular hemorrhage was observed in 66 (41.25%) patients with ICH. Multivariate analyses demonstrated that a short time from onset to baseline CT scan, the initial hematoma volume, and the presence of intraventricular hemorrhage on follow-up CT scan were independently associated with hematoma enlargement. The presence of intraventricular hemorrhage on follow-up CT scan can be associated with hematoma expansion in patients with ICH.
PMCID: PMC4471897  PMID: 26087142
10.  Over-expression of TWIST, an epithelial-mesenchymal transition inducer, predicts poor survival in patients with oral carcinoma 
TWIST, an epithelial-mesenchymal transition inducer, has been thought to play a critical role in the progression of a number of malignancies. Published studies reporting the association of TWIST expression with oral carcinoma risk has yielded conflicting results. Thus, we conducted a meta-analysis to address this controversy. After rigorous searching and screening, a total of seven studies were included. The results showed that the TWIST positive expression rate in oral cancer tissues was higher than that in the normal tissues. TWIST expression might have a correlation with clinical features such as low differentiation, advanced clinical stage, presence of lymph node metastasis and local recurrence, but not age, gender, T stage and smoking and drinking. The data suggested that TWIST might play critical roles in the cancer progression and act as a prognostic factor in oral cancer patients.
PMCID: PMC4537964  PMID: 26309581
TWIST; expression; metastasis; oral carcinoma; meta-analysis
11.  The decreased expression of miR-625 predicts poor prognosis of esophageal squamous cell carcinoma 
Background: Previous study has detected the expression of miR-625 in esophageal squamous cell carcinoma (ESCC) and found that miR-625 was related to tumor depth, stage, and metastasis of ESCC. However, the prognostic value of miR-625 in ESCC has not yet been reported. Methods: Real-time quantitative PCR was employed to measure the expression level of miR-625 in clinical ESCC tissues. Survival curves were made using the Kaplan-Meier method, and the log rank test was used to analyze the differences between clinicopathological characteristics and survival in ESCC patients. Results: The expression level of miR-625 in ESCC tissues was significantly lower than that in adjacent non-tumor tissues (1.00 ± 0.38 vs. 3.25 ± 1.83, P < 0.0001). Low miR-625 expression was observed to be closely correlated with lymph node metastasis (P = 0.01), distant metastasis (P = 0.007), tumor differentiation (P = 0.04), and advanced TNM stage (P = 0.005). The 5-year overall survival rate in the low expression group was 38.1%, compared with 68.8% in the high expression group (log-rank test, P = 0.001). Multivariate Cox regression analysis showed that miR-625 expression level (HR = 3.72, 95% CI: 1.36-8.78, P = 0.005) was an independent factor in predicting the overall survival of ESCC patients. Conclusion: Our findings provide the convincing evidence for the first time that the down-regulation of miR-625 may serve as a novel molecular marker to predict the aggressive tumor progression and unfavorable prognosis of ESCC patients.
PMCID: PMC4538131  PMID: 26309624
MiRNA-625; esophageal cancer; ESCC; clinicopathological features; prognosis
12.  Distinct domains in Bub1 localize RZZ and BubR1 to kinetochores to regulate the checkpoint 
Nature Communications  2015;6:7162.
The spindle assembly checkpoint (SAC) ensures proper chromosome segregation by delaying anaphase onset in response to unattached kinetochores. Checkpoint signalling requires the kinetochore localization of the Mad1–Mad2 complex that in more complex eukaryotes depends on the Rod–Zwilch–ZW10 (RZZ) complex. The kinetochore protein Zwint has been proposed to be the kinetochore receptor for RZZ, but here we show that Bub1 and not Zwint is required for RZZ recruitment. We find that the middle region of Bub1 encompassing a domain essential for SAC signalling contributes to RZZ localization. In addition, we show that a distinct region in Bub1 mediates kinetochore localization of BubR1 through direct binding, but surprisingly removal of this region increases checkpoint strength. Our work thus uncovers how Bub1 coordinates checkpoint signalling by distinct domains for RZZ and BubR1 recruitment and suggests that Bub1 localizes antagonistic checkpoint activities.
The spindle assembly checkpoint (SAC) depends on the recruitment of specific protein complexes to the kinetochore. Here Zhang et al. show that Bub1 recruits the RZZ complex and BubR1 to the kinetochore, and loss of the BubR1 binding sequence enhances checkpoint activity suggesting both SAC activating and silencing roles.
PMCID: PMC4458899  PMID: 26031201
13.  Magnetic resonance imaging of folic acid-coated magnetite nanoparticles reflects tissue biodistribution of long-acting antiretroviral therapy 
Regimen adherence, systemic toxicities, and limited drug penetrance to viral reservoirs are obstacles limiting the effectiveness of antiretroviral therapy (ART). Our laboratory’s development of the monocyte-macrophage-targeted long-acting nanoformulated ART (nanoART) carriage provides a novel opportunity to simplify drug-dosing regimens. Progress has nonetheless been slowed by cumbersome, but required, pharmacokinetic (PK), pharmacodynamics, and biodistribution testing. To this end, we developed a small magnetite ART (SMART) nanoparticle platform to assess antiretroviral drug tissue biodistribution and PK using magnetic resonance imaging (MRI) scans. Herein, we have taken this technique a significant step further by determining nanoART PK with folic acid (FA) decorated magnetite (ultrasmall superparamagnetic iron oxide [USPIO]) particles and by using SMART particles. FA nanoparticles enhanced the entry and particle retention to the reticuloendothelial system over nondecorated polymers after systemic administration into mice. These data were seen by MRI testing and validated by comparison with SMART particles and direct evaluation of tissue drug levels after nanoART. The development of alendronate (ALN)-coated magnetite thus serves as a rapid initial screen for the ability of targeting ligands to enhance nanoparticle-antiretroviral drug biodistribution, underscoring the value of decorated magnetite particles as a theranostic tool for improved drug delivery.
Video abstract
PMCID: PMC4461087  PMID: 26082630
folic acid; decorated nanoparticles; magnetite; theranostics; magnetic resonance imaging
14.  The long-term effects of superovulation on fertility and sexual behavior of male offspring in mice 
To evaluate the long-term effects of superovulation on fertility and sexual behavior of male offspring in mice.
The mice were superovaluted, and the fertility of male offspring (F1 generation and F2 generation) were evaluated in terms of the percentage of plugs and pregnancies, serum testosterone concentrations, and sperm motility. Furthermore, the sexual behavior of male offspring and sex ratio (F1 generation and F2 generation) were measured.
There were no significant differences in the percentage of plug and pregnancies, serum testosterone concentrations, sperm motilities and sex ratio between the offspring in naturally conceived group and superovulation groups (both F1 generation and F2 generation). The sperm hyperactivity at 90 min after incubation of F1 generation in naturally conceived group were higher than that of F1 generation in superovulation group, but the differences did not reach statistical significance. The offspring produced by superovaluted oocytes (both F1 generation and F2 generation) did not exhibit significant alterations in sexual behavior.
No significant alterations were found in fertility and sexual behavior of male offspring in mice produced by superovaluted oocytes compared with those of naturally conceived offspring.
PMCID: PMC4016376  PMID: 24510149
Superovulation; Male; Offspring; Fertility; Sexual behavior
15.  Controllable Thermal Rectification Realized in Binary Phase Change Composites 
Scientific Reports  2015;5:8884.
Phase transition is a natural phenomenon happened around our daily life, represented by the process from ice to water. While melting and solidifying at a certain temperature, a high heat of fusion is accompanied, classified as the latent heat. Phase change material (PCM) has been widely applied to store and release large amount of energy attributed to the distinctive thermal behavior. Here, with the help of nanoporous materials, we introduce a general strategy to achieve the binary eicosane/PEG4000 stuffed reduced graphene oxide aerogels, which has two ends with different melting points. It's successfully demonstrated this binary PCM composites exhibits thermal rectification characteristic. Partial phase transitions within porous networks instantaneously result in one end of the thermal conductivity saltation at a critical temperature, and therefore switch on or off the thermal rectification with the coefficient up to 1.23. This value can be further raised by adjusting the loading content of PCM. The uniqueness of this device lies in its performance as a normal thermal conductor at low temperature, only exhibiting rectification phenomenon when temperature is higher than a critical value. The stated technology has broad applications for thermal energy control in macroscopic scale such as energy-efficiency building or nanodevice thermal management.
PMCID: PMC4352864  PMID: 25748640
16.  Effect of hydrogen sulfide on inflammatory cytokines in acute myocardial ischemia injury in rats 
Hydrogen sulfide (H2S) is believed to be involved in numerous physiological and pathophysiological processes, and now it is recognized as the third endogenous signaling gasotransmitter, following nitric oxide and carbon monoxide; however, the effects of H2S on inflammatory factors in acute myocardial ischemia injury in rats have not been clarified. In the present study, sodium hydrosulfide (NaHS) was used as the H2S donor. Thirty-six male Sprague Dawley rats were randomly divided into five groups: Sham, ischemia, ischemia + low-dose (0.78 mg/kg) NaHS, ischemia + medium-dose (1.56 mg/kg) NaHS, ischemia + high-dose (3.12 mg/kg) NaHS and ischemia + propargylglycine (PPG) (30 mg/kg). The rats in each group were sacrificed 6 h after the surgery for sample collection. Compared with the ischemia group, the cardiac damage in the rats in the ischemia + NaHS groups was significantly reduced, particularly in the high-dose group; in the ischemia + PPG group, the myocardial injury was aggravated compared with that in the ischemia group. Compared with the ischemia group, the levels of interleukin (IL)-1β, IL-6 and tumor necrosis factor-α (TNF-α) in the serum of rats in the ischemia + medium- and high-dose NaHS groups were significantly reduced, and the expression of intercellular adhesion molecule-1 (ICAM-1) mRNA and nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) protein in the myocardial tissues of rats was significantly reduced. In the ischemia + PPG group, the TNF-α, IL-1β and IL-6 levels in the serum were significantly increased, the expression of ICAM-1 mRNA was increased, although without a significant difference, and the expression of NF-κB was increased. The findings of the present study provide novel evidence for the dual effects of H2S on acute myocardial ischemia injury via the modulation of inflammatory factors.
PMCID: PMC4316979  PMID: 25667680
hydrogen sulfide; acute myocardial ischemia; rat; inflammatory factor
17.  Polymorphism of the low-density lipoprotein receptor-related protein 5 gene and fracture risk 
Several molecular epidemiological studies have been conducted to examine the association between low-density lipoprotein receptor-related proteins (LRP5) Ala1330Val polymorphism and fracture; however, the conclusions remained controversial. We therefore performed an extensive meta-analysis on 10 published studies with 184479 subjects. Electronic databases, including PubMed, Excerpta Medica Database (EMBASE), Cochrane, Elsevier Science Direct and China National Knowledge Infrastructure (CNKI) databases were searched. Summary odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated using random-effects models. LRP5 Ala1330Val polymorphism was associated with a significantly increased risk of fracture (OR = 1.10; 95% CI, 1.06-1.14; I2 = 29%). We also found that this polymorphism increased fracture risk in Caucasians. In the subgroup analysis according to gender, women was significantly associated with risk of fracture. In the subgroup analysis by type of fracture, LRP5 Ala1330Val polymorphism showed increased osteoporotic fracture risk. In conclusion, this meta-analysis suggested that an increased risk of fracture was associated with the LRP5 Ala1330Val polymorphism.
PMCID: PMC4307457  PMID: 25664010
Fracture; low-density lipoprotein receptor-related protein; meta-analysis; polymorphism
18.  Optimal single-dose epidural neostigmine for postoperative analgesia after partial hepatectomy 
Indian Journal of Pharmacology  2014;46(6):613-616.
Neostigmine can produce analgesia by acting on the spinal cord. This study was to determine the optimal single-dose of epidural neostigmine for postoperative analgesia after partial hepatectomy.
Patients and Methods:
Twenty-six patients undergoing elective partial hepatectomy under general anesthesia combined with epidural block were studied. The dose of epidural neostigmine was determined using Dixon's up-and-down method, starting from neostigmine 100 μg with an interval of 25 μg. Thirty minutes after skin incision, a predetermined dose of neostigmine was injected via the epidural catheter. Each patient received 0.125% bupivacaine and fentanyl 2 μg/ml for patient controlled epidural analgesia (PCEA) after the operation. Assessment of analgesia quality was performed at 8 h and 24 h after the operation.
The ED50 of epidural neostigmine in combination with PCEA for satisfactory analgesia was 226.78 ± 33.20 μg. Probit analysis showed that the ED50 and ED95 of epidural neostigmine were 228.63 μg (95% CI = 197.95–299.77 μg) and 300.12 μg (95% CI = 259.44–741.65 μg), respectively.
The ED50 and ED95 of epidural neostigmine in combination with PCEA for satisfactory analgesia after partial hepatectomy were 228.63 μg (95% CI = 197.95–299.77 μg) and 300.12 μg (95% CI = 259.44–741.65 μg).
PMCID: PMC4264076  PMID: 25538332
Dixon's up-and-down method; neostigmine; optimal dose; postoperative analgesia; patient controlled epidural analgesia
19.  Real-Time Control of Uni-Directional Liquid Spreading on a Half-Cone Nanoshell Array 
Scientific Reports  2014;4:6751.
Half-cone nanoshell arrays, fabricated by a simple and efficient colloidal lithography method, enable uni-directional liquid spreading on their hydrophilic asymmetric nanostructured surface. The preferred direction of the liquid flow is reversed when the surface is made hydrophobic. Accordingly, poly(N-isopropyl-acrylamide) is polymerized onto the surface for in-site controlling the transition of liquid spreading direction via its temperature dependent hydrophobicity. Furthermore, we also explain theoretically, that the spreading direction on hexagonal nanocone arrays is independent of the lattice orientation and only depends on the slanting direction. The insights gained from this work offer new opportunities for smart microfluidics, water harvesting and making use of other wetting conditions on demand.
PMCID: PMC4208037  PMID: 25341416
20.  Layer-dependent Band Alignment and Work Function of Few-Layer Phosphorene 
Scientific Reports  2014;4:6677.
Using first-principles calculations, we study the electronic properties of few-layer phosphorene focusing on layer-dependent behavior of band gap, work function band alignment and carrier effective mass. It is found that few-layer phosphorene shows a robust direct band gap character, and its band gap decreases with the number of layers following a power law. The work function decreases rapidly from monolayer (5.16 eV) to trilayer (4.56 eV), and then slowly upon further increasing the layer number. Compared to monolayer phosphorene, there is a drastic decrease of hole effective mass along the ridge (zigzag) direction for bilayer phosphorene, indicating a strong interlayer coupling and screening effect. Our study suggests that 1). Few-layer phosphorene with a layer-dependent band gap and a robust direct band gap character is promising for efficient solar energy harvest. 2). Few-layer phosphorene outperforms monolayer counterpart in terms of a lighter carrier effective mass, a higher carrier density and a weaker scattering due to enhanced screening. 3). The layer-dependent band edges and work functions of few-layer phosphorene allow for modification of Schottky barrier with enhanced carrier injection efficiency. It is expected that few-layer phosphorene will present abundant opportunities for a plethora of new electronic applications.
PMCID: PMC4202206  PMID: 25327586
21.  Single nucleotide polymorphisms in VEGF gene are associated with an increased risk of osteosarcoma 
We aimed to assess whether the five common SNPs can affect the risk of osteosarcoma, and its association with demographic characteristics of osteosarcoma. 165 osteosarcoma patients and 330 cancer-free controls were enrolled into our study. Five common SNPs in VEGF gene, -2578C/A (rs699947), -1156G/A (rs1570360), +1612G/A (rs10434), +936C/T (rs3025039) and -634G/C (rs2010963), were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Conditional logistic regression analyses found that individuals with AA genotype and A allele of rs699947 were associated with an increased risk of osteosarcoma. Individuals with GG genotype and G allele of rs2010963 were associated with an increased risk of osteosarcoma. By stratified analysis, AA genotype of rs699947 was associated with an increased risk of osteosarcoma in those with shorter age, males and a family history of cancer, and GG genotype of rs2010963 was correlated with an increased risk of osteosarcoma in those with shorter age, females and a family history of cancer. Our study suggests that rs699947 and rs2010963 polymorphisms may play a role in the pathogenesis of osteosarcoma.
PMCID: PMC4270581  PMID: 25550863
Single nucleotide polymorphism; vascular endothelial growth factor; osteosarcoma
22.  Overexpression of hypoxia-inducible factor-1α and vascular endothelial growth factor in sacral giant cell tumors and the correlation with tumor microvessel density 
Although classified as benign, giant cell tumors of the bone (GCTB) may be aggressive, recur and even metastasize to the lungs. In addition, the pathogenesis and histogenesis remain unclear; thus, the driving factors behind the strong tumor growth capacity of GCTB require investigation. In the present study, the expression levels of hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF), which are promoted by hypoxic conditions, were determined in 22 sacral GCTB samples using immunohistochemistry and western blot analysis. Furthermore, CD34 expression was analyzed using these methods. The correlation between HIF-1α or VEGF expression and the tumor microvessel density (MVD) was then determined. The results demonstrated that HIF-1α, VEGF and CD34 were overexpressed in the 22 sacral GCTB specimens, and overexpression of HIF-1α and VEGF correlated with the tumor MVD. Thus, the present study has provided novel indicators for the tumor growth capacity of GCTBs.
PMCID: PMC4186367  PMID: 25289039
hypoxia inducible factor-1α; vascular endothelial growth factor; sacral giant cell tumors; microvessel density
23.  Induction of human chronic myeloid leukemia K562 cell apoptosis by virosecurinine and its molecular mechanism 
Molecular Medicine Reports  2014;10(5):2365-2371.
Virosecurinine is a major alkaloid of the plant Securinega suffruticosa and has been found to be a potent agent in inducing the differentiation of cancer cells. The present study aimed to investigate the antitumor effects of virosecurinine by inducing the apoptosis of leukemic K562 cells and to examine the underlying mechanisms. K562 cells were treated with different concentrations of virosecurinine (6.25, 12.5, 25, 50, 100 and 200 μmol/l) for 24, 48 and 72 h. The cell counting kit (CCK)-8 method was used to detect the antitumor effect of K562 cells in vitro. Flow cytometry was used to observe the apoptotic ratio and analyze the cell cycle following treatment with virosecurinine in K562 cells. Light and electron microscopy was used to identify morphological alterations in the virosecurinine-treated K562 cells. The mRNA levels of mammalian target of rapamycin (mTOR), SH2 domain-containing inositol-5′-phosphatase 2 (SHIP2), phosphatase and tensin homologue (PTEN) and breakpoint cluster region (BCR)/Abelson (ABL) were detected pre and post-virosecurinine treatment using reverse transcription quantitative polymerase chain reaction (RT-qPCR). The generation depression effects of K562 cells cultured in vitro were detected using CCK-8 technology, which revealed a dose and time-dependent association. The IC50 was 32.984 μmol/l at 48 h. Flow cytometric analysis indicated that treatment with virosecurinine at concentrations of 6.25, 25 and 50 μmol/l increased the apoptotic rate of the K562 cells and caused G1/S phase arrest. RT-qPCR indicated that virosecurinine upregulated the gene expression of PTEN and downregulated the expression of mTOR, SHIP-2 and BCR/ABL in K562 cells. Virosecurinine inhibited the growth and proliferation of the K562 cell lines and induced apoptosis in K562 cells by affecting the expression of mTOR, SHIP2, BCR/ABL and PTEN.
PMCID: PMC4214351  PMID: 25189629
virosecurinine; apoptosis; mammalian target of rapamycin; SH2 domain-containing inositol-5′-phosphatase 2; phosphatase and tensin homologue; breakpoint cluster region/Abelson; chronic myeloid leukemia; K562 cells
24.  Enhancement of NMDA receptor-mediated excitatory postsynaptic currents by gp120-treated macrophages: Implications for HIV-1-associated neuropathology 
A plethora of prior studies has linked HIV-1-infected and immune activated brain mononuclear phagocytes (MP; blood borne macrophages and microglia) to neuronal dysfunction. These are modulated by N-methyl-D-aspartate receptor (NMDAR) antagonists and supporting their relevance for HIV-1-associated nervous system disease. The role of NMDAR subsets in HIV-1-induced neuronal injury, nonetheless, is poorly understood. To this end, we investigated conditioned media from HIV-1gp120-treated human monocyte-derived-macrophages (MDM) for its ability to affact NMDAR-mediated excitatory postsynaptic currents (EPSCNMDAR) in rat hippocampal slices. Bath application of gp120-treated MDM-conditioned media (MCM) produced an increase of EPSCNMDAR. In contrast, control (untreated) MCM had limited effects on EPSCNMDAR. Testing NR2A NMDAR (NR2AR)-mediated EPSC (EPSCNR2AR) and NR2B NMDAR (NR2BR)-mediated EPSC (EPSCNR2BR) for MCM showed significant increased EPSCNR2BR when compared to EPSCNR2AR enhancement. When synaptic NR2AR-mediated EPSC was blocked by bath application of MK801 combined with low frequency stimulations, MCM retained its ability to enhance EPSCNMDAR evoked by stronger stimulations. This suggested that increase in EPSCNMDAR was mediated, in part, through extra-synaptic NR2BR. Further analyses revealed that the soluble factors with low (<3kD) to medium (3-10kD) molecular weight mediated the observed increases in EPSCNMDAR. The link between activation of NR2BRs and HIV-1gp120 MCM for neuronal injury was demonstrated by NR2BR but not NR2AR blockers. Taken together, these results indicate that macrophage secretory products induce neuronal injury through extra-synaptic NR2BRs.
PMCID: PMC3740075  PMID: 23660833
HIV-1gp120; Macrophages; NMDA receptors; EPSC; Neurotoxicity
25.  Endosomal Trafficking of Nanoformulated Antiretroviral Therapy Facilitates Drug Particle Carriage and HIV Clearance 
Journal of Virology  2014;88(17):9504-9513.
Limitations of antiretroviral therapy (ART) include poor patient adherence, drug toxicities, viral resistance, and failure to penetrate viral reservoirs. Recent developments in nanoformulated ART (nanoART) could overcome such limitations. To this end, we now report a novel effect of nanoART that facilitates drug depots within intracellular compartments at or adjacent to the sites of the viral replication cycle. Poloxamer 407-coated nanocrystals containing the protease inhibitor atazanavir (ATV) were prepared by high-pressure homogenization. These drug particles readily accumulated in human monocyte-derived macrophages (MDM). NanoATV concentrations were ∼1,000 times higher in cells than those that could be achieved by the native drug. ATV particles in late and recycling endosome compartments were seen following pulldown by immunoaffinity chromatography with Rab-specific antibodies conjugated to magnetic beads. Confocal microscopy provided cross validation by immunofluorescent staining of the compartments. Mathematical modeling validated drug-endosomal interactions. Measures of reverse transcriptase activity and HIV-1 p24 levels in culture media and cells showed that such endosomal drug concentrations enhanced antiviral responses up to 1,000-fold. We conclude that late and recycling endosomes can serve as depots for nanoATV. The colocalization of nanoATV at endosomal sites of viral assembly and its slow release sped antiretroviral activities. Long-acting nanoART can serve as a drug carrier in both cells and subcellular compartments and, as such, can facilitate viral clearance.
IMPORTANCE The need for long-acting ART is significant and highlighted by limitations in drug access, toxicity, adherence, and reservoir penetrance. We propose that targeting nanoformulated drugs to infected tissues, cells, and subcellular sites of viral replication may improve clinical outcomes. Endosomes are sites for human immunodeficiency virus assembly, and increasing ART concentrations in such sites enhances viral clearance. The current work uncovers a new mechanism by which nanoART can enhance viral clearance over native drug formulations.
PMCID: PMC4136325  PMID: 24920821

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