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1.  An in vivo Rat Model of Artery Buckling for Studying Wall Remodeling 
Annals of biomedical engineering  2014;42(8):1658-1667.
Theoretical modeling and in vitro experiments have demonstrated that arterial buckling is a possible mechanism for the development of artery tortuosity. However, there has been no report of whether artery buckling develops into tortuosity, partially due to the lack of in vivo models for long-term studies. The objective of this study was to establish an in vivo buckling model in rat carotid arteries for studying arterial wall remodeling after buckling. Rat left carotid arteries were transplanted to the right carotid arteries to generate buckling under in vivo pressure and were maintained for 1 week to examine wall remodeling and adaptation. Our results showed that a significant buckling was achieved in the carotid arterial grafts with altered wall stress. Cell proliferation and matrix metalloprotinease-2 (MMP-2) expression in the buckled arteries increased significantly compared with the controls. The tortuosity level of the grafts also slightly increased 1 week post-surgery, while there was no change in vessel dimensions, blood pressure, and blood flow velocity. The artery buckling model provides a useful tool for further study of the adaptation of arteries into tortuous shapes.
PMCID: PMC4099313  PMID: 24793586
artery remodeling; adaptation; buckling; tortuosity; cell proliferation; MMP-2/-9; animal model
2.  Pneumolysin Expression by Streptococcus pneumoniae Protects Colonized Mice from Influenza Virus-induced Disease 
Virology  2014;0:254-265.
The response to influenza virus (IAV) infection and severity of disease is highly variable in humans. We hypothesized that one factor contributing to this variability is the presence of specific respiratory tract (RT) microbes. One such microbe is Streptococcus pneumoniae (Sp) that is carried asymptomatically in the RT of many humans. In a mouse co-infection model we found that in contrast to secondary bacterial infection that exacerbates disease, Sp colonization 10 days prior to IAV protects from virus-induced morbidity and lung pathology. Using mutant Sp strains, we identified a critical role for the bacterial virulence factor pneumolysin (PLY) in mediating this protection. Colonization with the PLY-sufficient Sp strain induces expression of the immune-suppressive enzyme arginase 1 in alveolar macrophages (aMø) and correlates with attenuated recruitment and function of pulmonary inflammatory cells. Our study demonstrates a novel role for PLY in Sp-mediated protection by maintaining aMø as "gatekeepers" against virus-induced immunopathology.
PMCID: PMC4157663  PMID: 24999050
influenza virus; Streptococcus pneumoniae; pneumolysin; respiratory tract co-infection; immunopathology; alveolar macrophages; inflammatory monocytes; arginase I; iNOS; protection
3.  Activation of MrgC receptor inhibits N-type calcium channels in small-diameter primary sensory neurons in mice 
Pain  2014;155(8):1613-1621.
Mas-related G-protein-coupled receptor subtype C (mouse MrgC11 and rat rMrgC), expressed specifically in small-diameter primary sensory neurons, may constitute a novel pain inhibitory mechanism. We have shown previously that intrathecal administration of MrgC-selective agonists can strongly attenuate persistent pain in various animal models. However, the underlying mechanisms for MrgC agonist-induced analgesia remain elusive. Here, we conducted patch-clamp recordings to test the effect of MrgC agonists on high-voltage-activated (HVA) calcium current in small-diameter dorsal root ganglion (DRG) neurons. Using pharmacological approaches, we show for the first time that an MrgC agonist (JHU58) selectively and dose-dependently inhibits N-type, but not L- or P/Q-type, HVA calcium channels in mouse DRG neurons. Activation of HVA calcium channels is important to neurotransmitter release and synaptic transmission. Patch-clamp recordings in spinal cord slices showed that JHU58 attenuated the evoked excitatory postsynaptic currents in substantia gelatinosa (SG) neurons in wild-type mice, but not in Mrg knockout mice, after peripheral nerve injury. These findings indicate that activation of endogenously expressed MrgC receptors at central terminals of primary sensory fibers may decrease peripheral excitatory inputs onto SG neurons. Together, these results suggest potential cellular and molecular mechanisms that may contribute to intrathecal MrgC agonist-induced analgesia. Because MrgC shares substantial genetic homogeneity with human MrgX1, our findings may suggest a rationale for developing intrathecally delivered MrgX1 receptor agonists to treat pathological pain in humans and provide critical insight regarding potential mechanisms that may underlie its analgesic effects.
PMCID: PMC4104261  PMID: 24813294
MrgC; calcium channel; dorsal root ganglion; nerve injury; pain
4.  Secure Obfuscation for Encrypted Group Signatures 
PLoS ONE  2015;10(7):e0131550.
In recent years, group signature techniques are widely used in constructing privacy-preserving security schemes for various information systems. However, conventional techniques keep the schemes secure only in normal black-box attack contexts. In other words, these schemes suppose that (the implementation of) the group signature generation algorithm is running in a platform that is perfectly protected from various intrusions and attacks. As a complementary to existing studies, how to generate group signatures securely in a more austere security context, such as a white-box attack context, is studied in this paper. We use obfuscation as an approach to acquire a higher level of security. Concretely, we introduce a special group signature functionality-an encrypted group signature, and then provide an obfuscator for the proposed functionality. A series of new security notions for both the functionality and its obfuscator has been introduced. The most important one is the average-case secure virtual black-box property w.r.t. dependent oracles and restricted dependent oracles which captures the requirement of protecting the output of the proposed obfuscator against collision attacks from group members. The security notions fit for many other specialized obfuscators, such as obfuscators for identity-based signatures, threshold signatures and key-insulated signatures. Finally, the correctness and security of the proposed obfuscator have been proven. Thereby, the obfuscated encrypted group signature functionality can be applied to variants of privacy-preserving security schemes and enhance the security level of these schemes.
PMCID: PMC4517473  PMID: 26167686
5.  Comparative endocrinology of leptin: Assessing function in a phylogenetic context 
As we approach the end of two decades of leptin research, the comparative biology of leptin is just beginning. We now have several leptin orthologs described from nearly every major clade among vertebrates, and are moving beyond gene descriptions to functional studies. Even at this early stage, it is clear that non-mammals display clear functional similarities and differences with their better-studied mammalian counterparts. This review assesses what we know about leptin function in mammals and non-mammals, and gives examples of how these data can inform leptin biology in humans.
PMCID: PMC4128956  PMID: 24525452
6.  Autographa californica Multiple Nucleopolyhedrovirus ORF11 Is Essential for Budded-Virus Production and Occlusion-Derived-Virus Envelopment 
Journal of Virology  2014;89(1):373-383.
ORF11 (ac11) of Autographa californica multiple nucleopolyhedrovirus (AcMNPV) is a highly conserved gene with unknown function. To determine the role of ac11 in the baculovirus life cycle, an ac11 knockout mutant of AcMNPV, Ac11KO, was constructed. Northern blot and 5′ rapid amplification of cDNA ends (RACE) analyses revealed that ac11 is an early gene in the life cycle. Microscopy, titration assays, and Western blot analysis revealed that budded viruses (BVs) were not produced in Ac11KO-transfected Sf9 cells. However, quantitative PCR (qPCR) analysis demonstrated that the deletion of ac11 did not affect viral DNA replication. Furthermore, electron microscopy revealed that there was no nucleocapsid in the cytoplasm or plasma membrane of Ac11KO-transfected cells, which demonstrates that the defect in BV production in Ac11KO-transfected cells is due to the inefficient egress of nucleocapsids from the nucleus to the cytoplasm. In addition, electron microscopy observations showed that the nucleocapsids in the nucleus were not enveloped to form occlusion-derived viruses (ODVs) and that their subsequent embedding into occlusion bodies (OBs) was also blocked in Ac11KO-transfected cells, demonstrating that ac11 is required for ODV envelopment. These results therefore demonstrate that ac11 is an early gene that is essential for BV production and ODV envelopment.
IMPORTANCE Baculoviruses have been extensively used not only as specific, environmentally benign insecticides but also as helper-independent protein expression vectors. Although the function of baculovirus genes in viral replication has been studied by using gene knockout technology, the functions of more than one-third of viral genes, which include some highly conserved genes, are still unknown. In this study, ac11 was proven to play a crucial role in BV production and ODV envelopment. These results will lead to a better understanding of baculovirus infection cycles.
PMCID: PMC4301119  PMID: 25320313
7.  Effects of reducing dietary protein on the expression of nutrition sensing genes (amino acid transporters) in weaned piglets*  
The effects of crude protein (CP) levels in the diet on the mRNA expression of amino acid (AA) transporters were studied in a 45-d trial. Eighteen piglets with an initial body weight (BW) of 9.57 kg were assigned to three groups (14%, 17%, and 20% CP in the diet) in a completely randomized design (six replicates per treatment). Diets were supplemented with crystalline AA to achieve equal standardized ileal digestible contents of Lys, Met plus Cys, Thr, and Trp, and were provided ad libitum. After 45 d, all piglets were slaughtered to collect small intestine samples. Compared with the values in the 14% CP group, the expressions of ASCT2, 4F2hc, and ATB0 mRNA in the jejunum were increased by 23.00%, 12.00%, 6.00% and 48.00%, 47.00%, 56.00% in the 17% and 20% CP groups, respectively. These results indicate that a 14% CP diet supplemented with crystalline AA may not transport enough AA into the body and maintain growth performance of piglets. However, a reduction of dietary 17% CP may reduce the excretion of nitrogen into the environment while supporting the development of piglets. Therefore, the 17% CP level is more suitable than 14% CP level.
PMCID: PMC4471601  PMID: 26055911
Crude protein; Amino acid balance; Amino acid transporters
8.  Reminder systems to improve patient adherence to tuberculosis clinic appointments for diagnosis and treatment 
People with active tuberculosis (TB) require six months of treatment. Some people find it difficult to complete treatment, and there are several approaches to help ensure completion. One such system relies on reminders, where the health system prompts patients to attend for appointments on time, or re-engages people who have missed or defaulted on a scheduled appointment.
To assess the effects of reminder systems on improving attendance at TB diagnosis, prophylaxis, and treatment clinic appointments, and their effects on TB treatment outcomes.
Search methods
We searched the Cochrane Infectious Diseases Group Specialized Register, Cochrane Effective Practice andOrganization of Care Group Specialized Register, CENTRAL,MEDLINE, EMBASE, LILACS, CINAHL, SCI-EXPANDED, SSCI, m RCT, and the Indian Journal of Tuberculosis without language restriction up to 29 August 2014. We also checked reference lists and contacted researchers working in the field.
Selection criteria
Randomized controlled trials (RCTs), including cluster RCTs and quasi-RCTs, and controlled before-and-after studies comparing reminder systems with no reminders or an alternative reminder system for people with scheduled appointments for TB diagnosis, prophylaxis, or treatment.
Data collection and analysis
Two review authors independently extracted data and assessed the risk of bias in the included trials. We compared the effects of interventions by using risk ratios (RR) and presented RRs with 95% confidence intervals (CIs). Also we assessed the quality of evidence using the GRADE approach.
Main results
Nine trials, including 4654 participants, met our inclusion criteria. Five trials evaluated appointment reminders for people on treatment for active TB, two for people on prophylaxis for latent TB, and four for people undergoing TB screening using skin tests.We classified the interventions into 'pre-appointment' reminders (telephone calls or letters prior to a scheduled appointment) or'default' reminders (telephone calls, letters, or home visits to people who had missed an appointment).
For people being treated for active TB, clinic attendance and TB treatment completion were higher in people receiving pre-appointment reminder phone-calls (clinic attendance: 66% versus 50%; RR 1.32, 95% CI 1.10 to 1.59, one trial (USA), 615 participants, low quality evidence; TB treatment completion: 100% versus 88%; RR 1.14, 95% CI 1.02 to 1.27, one trial (Thailand), 92 participants, low quality evidence). Clinic attendance and TB treatment completion were also higher with default reminders (letters or home visits) (clinic attendance: 52% versus 10%; RR 5.04, 95% CI 1.61 to 15.78, one trial (India), 52 participants, low quality evidence; treatment completion: RR 1.17, 95% CI 1.11 to 1.24, two trials (Iraq and India), 680 participants, moderate quality evidence).
For people on TB prophylaxis, clinic attendance was higher with a policy of pre-appointment phone-calls (63% versus 48%; RR 1.30, 95% CI 1.07 to 1.59, one trial (USA), 536 participants); and attendance at the final clinic was higher with regular three-monthly phone-calls or nurse visits (93% versus 65%, one trial (Spain), 318 participants).
For people undergoing screening for TB, three trials of pre-appointment phone-calls found little or no effect on the proportion of people returning to clinic for the result of their skin test (three trials, 1189 participants, low quality evidence), and two trials found little or no effect with take home reminder cards (two trials, 711 participants). All four trials were conducted among healthy volunteers in the USA.
Authors' conclusions
Policies of sending reminders to people pre-appointment, and contacting people who miss appointments, seem sensible additions to any TB programme, and the limited evidence available suggests they have small but potentially important benefits. Future studies of modern technologies such as short message service (SMS) reminders would be useful, particularly in low-resource settings.
Plain Language Summary
Reminder systems to improve patient attendance at tuberculosis clinics
This Cochrane Review summarizes trials evaluating the effects of reminder systems on attendance at tuberculosis (TB) clinics and completion of TB treatment. After searching for relevant trials up to 29 August 2014, we included nine trials, including 4654 people.
What are reminder systems and how might they help?
Effective treatment for TB requires people to take multiple drugs daily for at least six months. Consequently, once they start to feel well again, some patients stop attending clinics and stop taking theirmedication which can lead to the illness returning and the development of drug resistance. One strategy theWorldHealthOrganization recommends is that an appointed person (a health worker or volunteer) watches the person take their medication everyday (called direct observation). Other strategies include reminder systems to prompt patients to attend for appointments on time, or to re-engage people who have missed or defaulted on a scheduled appointment. These prompts may be in the form of telephone calls or letters before the next scheduled appointment (“pre-appointment reminders”), or phone calls, letters, or home visits after a missed appointment (“default reminders”).
What the research says:
For people being treated for active TB:
- More people attended the clinic and completed TB treatment with pre-appointment reminder phone-calls (low quality evidence).- More people attended the clinic and completed TB treatment with a policy of default reminders (low and moderate quality evidence respectively).
For people on TB prophylaxis:
- More people attended the clinic with pre-appointment phone-calls, and the number attending the final clinic was higher with threemonthly phone-calls or nurse home visits.
For people being treated for active TB:
- Similar numbers of people attended clinic for skin test reading with and without pre-appointment phone-calls (low quality evidence).- Similar numbers of people attended clinic for skin test reading with and without take home reminder cards.
PMCID: PMC4448217  PMID: 25403701
9.  Early quantitative CT analysis of oleic acid induced acute respiratory distress syndrome in a canine model 
Background: Although quantitative computed tomography (CT) has been used to analyze the lungs of patients with confirmed diagnoses of acute respiratory distress syndrome (ARDS), there are few reports to show the diagnosis during the early stage of ARDS. Using a canine model and quantitative CT, we aimed to develop an oleic acid (OA) induced ARDS regarding the early stage of ARDS that could improve in the early diagnosis of ARDS. Methods: Fourteen healthy beagle dogs underwent CT. Their lung tissue was manually partitioned into four compartments, i.e., non-aerated, poorly aerated, normally aerated, and hyper-aerated lung compartments. The mean CT attenuation value Hounsfield unit (HU), tissue mass (g), residual volume (ml), and percentage of lung area were automatically determined for each lung compartment and compared between groups by receiver operating characteristic curve (ROC) analyses using area under curve (AUC). The optimized cut-off point for each parameter was determined by Youden’s index. Results: Regarding lung compartments during the expiratory phase, the percentage of non-aerated lung area in the ARDS group was higher vs. controls at all time points (T1 to T6). CT attenuation values for the ARDS group increased with time during both respiratory phases compared with controls. During both respiratory phases, tissue mass within the ARDS group significantly increased compared with controls at T3-T6. Conclusions: Quantitative CT analysis can detect ARDS at an early stage with high sensitivity and specificity, providing a minimum of assistance in the early diagnosis of ARDS.
PMCID: PMC4509184  PMID: 26221239
Acute respiratory distress syndrome; computed tomography; quantitative analysis; canine model; attenuation value; Hounsfield unit
10.  ATM couples replication stress and metabolic reprogramming during cellular senescence 
Cell reports  2015;11(6):893-901.
Replication stress induced by nucleotide deficiency plays an important role in cancer initiation. Replication stress in primary cells typically activates the cellular senescence tumor suppression mechanism. Senescence bypass correlates with development of cancer, a disease characterized by metabolic reprogramming. However, the role of metabolic reprogramming in cellular response to replication stress is unknown. Here we report that ATM plays a central role in regulating cellular response to replication stress by shifting cellular metabolism. ATM inactivation bypasses senescence induced by replication stress triggered by nucleotide deficiency. This was due to restoration of dNTP levels through both upregulation of the pentose phosphate pathway via increased G6PD activity and enhanced glucose and glutamine consumption. These phenotypes were mediated by a coordinated suppression of p53 and upregulation of c-MYC downstream of ATM inactivation. Our data indicate that ATM status couples replication stress and metabolic reprogramming during senescence.
PMCID: PMC4431925  PMID: 25937285
11.  Effectiveness of peer support for improving glycaemic control in patients with type 2 diabetes: a meta-analysis of randomized controlled trials 
BMC Public Health  2015;15:471.
To assess the effects of peer support at improving glycemic control in patients with type 2 diabetes.
Relevant electronic databases were sought for this investigation up to Dec 2014. Randomized controlled trials involving patients with type 2 diabetes that evaluated the effect of peer support on glycated hemoglobin (HbA1c) concentrations were included. The pooled mean differences (MD) between intervention and control groups with 95% confidence interval (CI) were calculated using random-effects model. The Cochrane Collaboration’s tool was used to assess the risk of bias.
Thirteen randomized controlled trials met the inclusion criteria. Peer support resulted in a significant reduction in HbA1c (MD −0.57 [95% CI: −0.78 to −0.36]). Programs with moderate or high frequency of contact showed a significant reduction in HbA1c levels (MD −0.52 [95% CI: −0.60 to −0.44] and −0.75 [95% CI: −1.21 to −0.29], respectively), whereas programs with low frequency of contact showed no significant reduction (MD −0.32 [95% CI: −0.74 to 0.09]). The reduction in HbA1c were greater among patients with a baseline HbA1c ≥ 8.5% (MD −0.78 [95% CI: −1.06 to −0.51]) and between 7.5 ~ 8.5% (MD −0.76 [95% CI: −1.05 to −0.47]), than patients with HbA1c < 7.5% (MD −0.08 [95% CI: −0.32 to 0.16]).
Peer support had a significant impact on HbA1c levels among patients with type 2 diabetes. Priority should be given to programs with moderate or high frequency of contact for target patients with poor glycemic control rather than programs with low frequency of contact that target the overall population of patients.
Electronic supplementary material
The online version of this article (doi:10.1186/s12889-015-1798-y) contains supplementary material, which is available to authorized users.
PMCID: PMC4425885  PMID: 25943398
Peer support; Randomized control trial; Type 2 diabetes; Meta-analysis
12.  Vascular endothelial growth factor polymorphisms and lung cancer risk 
The VEGF polymorphisms has been implicated in the susceptibility to lung cancer, but the results are not conclusive. The aim of this study is to investigate the association between the VEGF polymorphisms and the risk of lung cancer by meta-analysis. We searched PubMed, Embase, CNKI and Wanfang databases. A total of 7 case-control studies were included in this meta-analysis. We found that VEGF rs833061 polymorphism showed no significant association with lung cancer risk. Subgroup analysis on race suggested that CC genotype was significantly associated with lung cancer risk in Asian population. We found that VEGF rs699947 polymorphism showed significant association with lung cancer risk. Subgroup analysis on race showed that VEGF rs699947 polymorphism increased lung cancer risk in Asians. In conclusion, this meta-analysis suggested that the VEGF rs699947 is associated with increased risk of lung cancer.
PMCID: PMC4483952  PMID: 26131266
Lung cancer; VEGF; meta-analysis
13.  Cadherin-7 Function in Zebrafish Development 
Cell and tissue research  2008;334(1):37-45.
Cadherin cell adhesion molecules play crucial roles in vertebrate development. Most studies have focused on examining functions of classical type I cadherins (e.g. cadherin-2) in the vertebrate development. There is little information on the function of classical type II cadherins (e.g. cadherin-7) in vertebrate development. We previously showed that cadherin-7 mRNA exhibited a dynamic expression pattern in the central nervous system and notochord in embryonic zebrafish. To gain insight into cadherin-7 role in the formation of these structures, we analyzed their formation in zebrafish embryos injected with cadherin-7 specific antisense morpholino oligonucleotides (MO). Notochord development was severely disrupted in MO-injected embryos, whereas gross defects in central nervous system development were not detected in MO-injected embryos. Our results show that cadherin-7 plays an important role in the normal development of the zebrafish notochord.
PMCID: PMC4379488  PMID: 18665394
cell adhesion molecules; notochord; central nervous system; antisense morpholino oligonucleotides
14.  A quorum sensing-based in vivo expression system and its application in multivalent bacterial vaccine 
Delivery of antigens by live bacterial carriers can elicit effective humoral and cellular responses and may be an attractive strategy for live bacterial vaccine production through introduction of a vector that expresses an exogenous protective antigen. To overcome the instability and metabolic burden associated with plasmid introduction, alternative strategies, such as the use of in vivo-inducible promoters, have been proposed. However, screening an ideal in vivo-activated promoter with high efficiency and low leak expression in a particular strain poses great challenges to many researchers.
In this work, we constructed an in vivo antigen-expressing vector suitable for Edwardsiella tarda, an enteric Gram-negative invasive intracellular pathogen of both animals and humans. By combining quorum sensing genes from Vibrio fischeri with iron uptake regulons, a synthetic binary regulation system (ironQS) for E. tarda was designed. In vitro expression assay demonstrated that the ironQS system is only initiated in the absence of Fe2+ in the medium when the cell density reaches its threshold. The ironQS system was further confirmed in vivo to present an in vivo-triggered and cell density-dependent expression pattern in larvae and adult zebrafish. A recombinant E. tarda vector vaccine candidate WED(ironQS-G) was established by introducing gapA34, which encodes the protective antigen glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from the fish pathogen Aeromonas hydrophila LSA34 into ironQS system, and the immune protection afforded by this vaccine was assessed in turbot (Scophtalmus maximus). Most of the vaccinated fish survived under the challenge with A. hydrophila LSA34 (RPS = 67.0%) or E. tarda EIB202 (RPS = 72.3%).
Quorum sensing system has been extensively used in various gene structures in synthetic biology as a well-functioning and population-dependent gene circuit. In this work, the in vivo expression system, ironQS, maintained the high expression efficiency of the quorum sensing circuit and achieved excellent expression regulation of the Fur box. The ironQS system has great potential in applications requiring in vivo protein expression, such as vector vaccines. Considering its high compatibility, ironQS system could function as a universal expression platform for a variety of bacterial hosts.
PMCID: PMC4372277  PMID: 25888727
Bacterial vector vaccine; Edwardsiella tarda; Iron uptake system; In vivo expression; Quorum sensing
15.  Aldehyde dehydrogenase 1A1 circumscribes high invasive glioma cells and predicts poor prognosis 
American Journal of Cancer Research  2015;5(4):1471-1483.
Glioma is the most aggressive brain tumor with high invasiveness and poor prognosis. More reliable, sensitive and practical biomarkers to reveal glioma high invasiveness remain to be explored for the guidance of therapy. We herein evaluated the diagnostic and prognostic value of aldehyde dehydrogenase 1A1 (ALDH1A1) in the glioma specimens from 237 patients, and found that ADLH1A1 was frequently overexpressed in the high-grade glioma (WHO grade III-IV) as compared to the low-grade glioma (WHO grade I-II) patients. The tumor cells with ALDH1A1 expression were more abundant in the region between tumor and the borderline of adjacent tissue as compared to the central part of the tumor. ALDH1A1 overexpression was associated with poor differentiation and dismal prognosis. Notably, the overall and disease-free survivals of the patients who had ALDH1A1+ tumor cells sparsely located in the adjacent tissue were much worse. Furthermore, ALDH1A1 expression was correlated with the “classical-like” (CL) subtype as we examined GBM specimens from 72 patients. Multivariate Cox regression analysis revealed that ALDH1A1 was an independent marker for glioma patients’ outcome. Mechanistically, both in vitro and in vivo studies revealed that ALDH1A1+ cells isolated from either a glioblastoma cell line U251 or primary glioblastoma cells displayed significant invasiveness, clonogenicity, and proliferation as compared to ALDH1A1- cells, due to increased levels of mRNA and protein for matrix metalloproteinase 2, 7 and 9 (MMP2, MMP7 and MMP9). These results indicate that ALDH1A1+ cells contribute to the progression of glioma including invasion, proliferation and poor prognosis, and suggest that targeting ALDH1A1 may have important implications for the treatment of highly invasive glioma.
PMCID: PMC4473324  PMID: 26101711
ALDH1A1; glioma; invasion; matrix metalloproteinase; prognosis
16.  Determination of the Optimal Dose Reduction Level via Iterative Reconstruction Using 640-Slice Volume Chest CT in a Pig Model 
PLoS ONE  2015;10(3):e0117213.
To determine the optimal dose reduction level of iterative reconstruction technique for paediatric chest CT in pig models.
Materials and Methods
27 infant pigs underwent 640-slice volume chest CT with 80kVp and different mAs. Automatic exposure control technique was used, and the index of noise was set to SD10 (Group A, routine dose), SD12.5, SD15, SD17.5, SD20 (Groups from B to E) to reduce dose respectively. Group A was reconstructed with filtered back projection (FBP), and Groups from B to E were reconstructed using iterative reconstruction (IR). Objective and subjective image quality (IQ) among groups were compared to determine an optimal radiation reduction level.
The noise and signal-to-noise ratio (SNR) in Group D had no significant statistical difference from that in Group A (P = 1.0). The scores of subjective IQ in Group A were not significantly different from those in Group D (P>0.05). There were no obvious statistical differences in the objective and subjective index values among the subgroups (small, medium and large subgroups) of Group D. The effective dose (ED) of Group D was 58.9% lower than that of Group A (0.20±0.05mSv vs 0.48±0.10mSv, p <0.001).
In infant pig chest CT, using iterative reconstruction can provide diagnostic image quality; furthermore, it can reduce the dosage by 58.9%.
PMCID: PMC4357454  PMID: 25764485
17.  MrgC agonism at central terminals of primary sensory neurons inhibits neuropathic pain 
Pain  2013;155(3):534-544.
Chronic neuropathic pain is often refractory to current pharmacotherapies. The rodent Mas-related G-protein-coupled receptor subtype C (MrgC) shares substantial homogeneity with its human homolog, MrgX1, and is located specifically in small-diameter dorsal root ganglion (DRG) neurons. However, evidence regarding the role of MrgC in chronic pain conditions has been disparate and inconsistent. Accordingly, the therapeutic value of MrgX1 as a target for pain treatment in humans remains uncertain. Here, we found that intrathecal injection of BAM8-22 (a 15-amino acid peptide MrgC agonist) and JHU58 (a novel dipeptide MrgC agonist) inhibited both mechanical and heat hypersensitivity in rats after an L5 spinal nerve ligation (SNL). Intrathecal JHU58-induced pain inhibition was dose-dependent in SNL rats. Importantly, drug efficacy was lost in Mrg-cluster gene knockout (Mrg KO) mice and was blocked by gene silencing with intrathecal MrgC siRNA and by a selective MrgC receptor antagonist in SNL rats, suggesting that the drug action is MrgC-dependent. Further, in a mouse model of trigeminal neuropathic pain, microinjection of JHU58 into ipsilateral subnucleus caudalis inhibited mechanical hypersensitivity in wild-type but not Mrg KO mice. Finally, JHU58 attenuated the mEPSC frequency both in medullary dorsal horn neurons of mice after trigeminal nerve injury and in lumbar spinal dorsal horn of mice after SNL. We provide multiple lines of evidence that MrgC agonism at spinal but not peripheral sites may constitute a novel pain inhibitory mechanism that involves inhibition of peripheral excitatory inputs onto postsynaptic dorsal horn neurons in different rodent models of neuropathic pain.
PMCID: PMC3945061  PMID: 24333779
MrgC; dorsal root ganglion; spinal cord; neuropathic pain; analgesia
18.  Joint analysis of three genome-wide association studies of esophageal squamous cell carcinoma in Chinese populations 
Wu, Chen | Wang, Zhaoming | Song, Xin | Feng, Xiao-Shan | Abnet, Christian C. | He, Jie | Hu, Nan | Zuo, Xian-Bo | Tan, Wen | Zhan, Qimin | Hu, Zhibin | He, Zhonghu | Jia, Weihua | Zhou, Yifeng | Yu, Kai | Shu, Xiao-Ou | Yuan, Jian-Min | Zheng, Wei | Zhao, Xue-Ke | Gao, She-Gan | Yuan, Zhi-Qing | Zhou, Fu-You | Fan, Zong-Min | Cui, Ji-Li | Lin, Hong-Li | Han, Xue-Na | Li, Bei | Chen, Xi | Dawsey, Sanford M. | Liao, Linda | Lee, Maxwell P. | Ding, Ti | Qiao, You-Lin | Liu, Zhihua | Liu, Yu | Yu, Dianke | Chang, Jiang | Wei, Lixuan | Gao, Yu-Tang | Koh, Woon-Puay | Xiang, Yong-Bing | Tang, Ze-Zhong | Fan, Jin-Hu | Han, Jing-Jing | Zhou, Sheng-Li | Zhang, Peng | Zhang, Dong-Yun | Yuan, Yuan | Huang, Ying | Liu, Chunling | Zhai, Kan | Qiao, Yan | Jin, Guangfu | Guo, Chuanhai | Fu, Jianhua | Miao, Xiaoping | Lu, Changdong | Yang, Haijun | Wang, Chaoyu | Wheeler, William A. | Gail, Mitchell | Yeager, Meredith | Yuenger, Jeff | Guo, Er-Tao | Li, Ai-Li | Zhang, Wei | Li, Xue-Min | Sun, Liang-Dan | Ma, Bao-Gen | Li, Yan | Tang, Sa | Peng, Xiu-Qing | Liu, Jing | Hutchinson, Amy | Jacobs, Kevin | Giffen, Carol | Burdette, Laurie | Fraumeni, Joseph F. | Shen, Hongbing | Ke, Yang | Zeng, Yixin | Wu, Tangchun | Kraft, Peter | Chung, Charles C. | Tucker, Margaret A. | Hou, Zhi-Chao | Liu, Ya-Li | Hu, Yan-Long | Liu, Yu | Wang, Li | Yuan, Guo | Chen, Li-Sha | Liu, Xiao | Ma, Teng | Meng, Hui | Sun, Li | Li, Xin-Min | Li, Xiu-Min | Ku, Jian-Wei | Zhou, Ying-Fa | Yang, Liu-Qin | Wang, Zhou | Li, Yin | Qige, Qirenwang | Yang, Wen-Jun | Lei, Guang-Yan | Chen, Long-Qi | Li, En-Min | Yuan, Ling | Yue, Wen-Bin | Wang, Ran | Wang, Lu-Wen | Fan, Xue-Ping | Zhu, Fang-Heng | Zhao, Wei-Xing | Mao, Yi-Min | Zhang, Mei | Xing, Guo-Lan | Li, Ji-Lin | Han, Min | Ren, Jing-Li | Liu, Bin | Ren, Shu-Wei | Kong, Qing-Peng | Li, Feng | Sheyhidin, Ilyar | Wei, Wu | Zhang, Yan-Rui | Feng, Chang-Wei | Wang, Jin | Yang, Yu-Hua | Hao, Hong-Zhang | Bao, Qi-De | Liu, Bao-Chi | Wu, Ai-Qun | Xie, Dong | Yang, Wan-Cai | Wang, Liang | Zhao, Xiao-Hang | Chen, Shu-Qing | Hong, Jun-Yan | Zhang, Xue-Jun | Freedman, Neal D | Goldstein, Alisa M. | Lin, Dongxin | Taylor, Philip R. | Wang, Li-Dong | Chanock, Stephen J.
Nature genetics  2014;46(9):1001-1006.
We conducted a joint (pooled) analysis of three genome-wide association studies (GWAS) 1-3 of esophageal squamous cell carcinoma (ESCC) in ethnic Chinese (5,337 ESCC cases and 5,787 controls) with 9,654 ESCC cases and 10,058 controls for follow-up. In a logistic regression model adjusted for age, sex, study, and two eigenvectors, two new loci achieved genome-wide significance, marked by rs7447927 at 5q31.2 (per-allele odds ratio (OR) = 0.85, 95% CI 0.82-0.88; P=7.72x10−20) and rs1642764 at 17p13.1 (per-allele OR= 0.88, 95% CI 0.85-0.91; P=3.10x10−13). rs7447927 is a synonymous single nucleotide polymorphism (SNP) in TMEM173 and rs1642764 is an intronic SNP in ATP1B2, near TP53. Furthermore, a locus in the HLA class II region at 6p21.32 (rs35597309) achieved genome-wide significance in the two populations at highest risk for ESSC (OR=1.33, 95% CI 1.22-1.46; P=1.99x10−10). Our joint analysis identified new ESCC susceptibility loci overall as well as a new locus unique to the ESCC high risk Taihang Mountain region.
PMCID: PMC4212832  PMID: 25129146
19.  Genes Underlying Positive Influence of Prenatal Environmental Enrichment and Negative Influence of Prenatal Earthquake Simulation and Corrective Influence of Chinese Herbal Medicine on Rat Offspring: Irf7 and Ninj2 
Prenatal environmental enrichment (EE) has been proven to positively affect but prenatal stress negatively influence the physiological and psychological processes in animals, whose trans-generational genetic mechanism remains unclearly defined. We aimed to investigate and find out key genes underlying the positive-negative effects derived from prenatal interventions.
Materials and Methods
Pregnant rats were randomized into EE group (EEG), earthquake simulation group (ESG), herbal group (HG) received herbal supplements in feed after earthquake simulation, and control group (CG).
Light Box Defecation Test (LBDT) showed EEG offspring presented less fecal pellets than CG offspring, ESG's more than CG's, and HG's less than ESG (p's<0.05). Open-field Test (OFT) score of EEG was higher than CG offspring, of ESG's was lower than CG's, and HG's higher than ESG's. Irf7 and Ninj were screened, which were up-regulated in EEG, down-regulated in ESG (FC<0.5), and were neutralized in HG. Prenatal EE could positively promote the nervous system development, prenatal earthquake simulation could retard the nervous system development and Chinese herbal remedy (JKSQW) which could correct the retardation.
The negative-positive prenatal effect could contribute to altered gene expression of Irf7 and Ninj2 which also could play a key role in the improving function of JKSQW for the kidneys.
PMCID: PMC4202648  PMID: 25435624
Prenatal stress; Earthquake simulation; Light Box Defecation Test; Open-field Test; Irf7; Ninj2
20.  Decision-Making for Risky Gains and Losses among College Students with Internet Gaming Disorder 
PLoS ONE  2015;10(1):e0116471.
Individuals with Internet gaming disorder (IGD) tend to exhibit disadvantageous risky decision-making not only in their real life but also in laboratory tasks. Decision-making is a complex multifaceted function and different cognitive processes are involved in decision-making for gains and losses. However, the relationship between impaired decision-making and gain versus loss processing in the context of IGD is poorly understood. The main aim of the present study was to separately evaluate decision-making for risky gains and losses among college students with IGD using the Cups task. Additionally, we further examined the effects of outcome magnitude and probability level on decision-making related to risky gains and losses respectively. Sixty college students with IGD and 42 matched healthy controls (HCs) participated. Results indicated that IGD subjects exhibited generally greater risk taking tendencies than HCs. In comparison to HCs, IGD subjects made more disadvantageous risky choices in the loss domain (but not in the gain domain). Follow-up analyses indicated that the impairment was associated to insensitivity to changes in outcome magnitude and probability level for risky losses among IGD subjects. In addition, higher Internet addiction severity scores were associated with percentage of disadvantageous risky options in the loss domain. These findings emphasize the effect of insensitivity to losses on disadvantageous decisions under risk in the context of IGD, which has implications for future intervention studies.
PMCID: PMC4304794  PMID: 25615595
21.  Delayed cardioprotection by sevoflurane preconditioning: a novel mechanism via inhibiting Beclin 1-mediated autophagic cell death in cardiac myocytes exposed to hypoxia/reoxygenation injury 
Sevoflurane preconditioning has shown to exert delayed caridioprotection against subsequent ischemia and reperfusion injury, but the mechanisms underlying is unclear. Inhibition of autophagy by 3-methyladenine (3-MA) or knockdown of Beclin 1 leads to enhanced cardiac myocyte survival. Our study aimed to test whether sevoflurane preconditioning provides a second window of anesthetic preconditioning (SWOP) via inhibit Beclin 1-mediated autophagic cell death. H9c2 rat cardiomyocytes were randomly divided into five groups: Control (CON) group; hypoxia/reoxygenation (H/R) group, rat cardiomyocytes was exposed in the airtight container for 2 h followed by 1 h of reoxgenation; SWOP group, rat cardiomyocytes was exposed to 1 h of 2.5% sevoflurane 24 h before H/R; Autophagic inhibitors, 3-methyladenine (3-MA, 10 mM) was added to culture medium 15 min before sevoflurane exposure (3-MA+SWOP group) or cells were treated by 3-MA alone (3-MA group). The cell proliferation was significantly increased in SWOP group (79.49 ± 1.37%, P < 0.05) when compared to H/R group (62.2 ± 6.49%, P < 0.05). 3-MA administered before SWOP significantly attenuated the H/R induced autophagy and cell death. H/R injury up-regulated the expression of LC3-II and Beclin 1 proteins (342 ± 66% and 163 ± 18%, respectively, P < 0.05) compared to the CON group (100%), which were increased in SWOP group (202 ± 77% and 128 ± 8%, respectively, P < 0.05). The expression of LC3-II and Beclin 1 proteins was decreased in 3-MA group (110 ± 28% and 97 ± 6%, respectively) and 3-MA+SWOP group (93 ± 7% and 98 ± 6%, respectively) compared with H/R group, but Bcl-2 was upregulated in 3-MA group (158 ± 4%) and 3-MA+SWOP group (156 ± 5%) compared to H/R group (103 ± 7%). In conclusion, sevoflurane preconditioning confers delayed cardioprotection via inhibition Beclin 1-mediated autophagic cell death in cardiac myocytes 24 h before exposed to H/R injury.
PMCID: PMC4348939  PMID: 25755708
Autophagy; Beclin 1; hypoxia/reoxgenation; sevoflurane
22.  Sevoflurane Postconditioning Protects Rat Hearts against Ischemia-Reperfusion Injury via the Activation of PI3K/AKT/mTOR Signaling 
Scientific Reports  2014;4:7317.
Phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway plays a key role in myocardial ischemia-reperfusion (I/R) injury. Mammalian target of rapamycin (mTOR), a downstream target of PI3K/AKT signaling, is necessary and sufficient to protect the heart from I/R injury. Inhaled anesthetic sevoflurane is widely used in cardiac surgeries because its induction and recovery are faster and smoother than other inhaled anesthetics. Sevoflurane proved capable of inducing postconditioning effects in the myocardium. However, the underlying molecular mechanisms for sevoflurane-induced postconditioning (SPC) were largely unclear. In the present study, we demonstrated that SPC protects myocardium from I/R injury with narrowed cardiac infarct focus, increased ATP content, and decreased cardiomyocyte apoptosis, which are mainly due to the activation of PI3K/AKT/mTOR signaling and the protection of mitochondrial energy metabolism. Application of dactolisib (BEZ235), a PI3K/mTOR dual inhibitor, abolishes the up-regulation of pho-AKT, pho-GSK, pho-mTOR, and pho-p70s6k induced by SPC, hence abrogating the anti-apoptotic effect of sevoflurane and reducing SPC-mediated protection of heart from I/R injury. As such, this study proved that PI3K/AKT/mTOR pathway plays an important role in SPC induced cardiac protection against I/R injury.
PMCID: PMC4255182  PMID: 25471136
23.  BCDP: Budget Constrained and Delay-Bounded Placement for Hybrid Roadside Units in Vehicular Ad Hoc Networks 
Sensors (Basel, Switzerland)  2014;14(12):22564-22594.
In vehicular ad hoc networks, roadside units (RSUs) placement has been proposed to improve the the overall network performance in many ITS applications. This paper addresses the budget constrained and delay-bounded placement problem (BCDP) for roadside units in vehicular ad hoc networks. There are two types of RSUs: cable connected RSU (c-RSU) and wireless RSU (w-RSU). c-RSUs are interconnected through wired lines, and they form the backbone of VANETs, while w-RSUs connect to other RSUs through wireless communication and serve as an economical extension of the coverage of c-RSUs. The delay-bounded coverage range and deployment cost of these two cases are totally different. We are given a budget constraint and a delay bound, the problem is how to find the optimal candidate sites with the maximal delay-bounded coverage to place RSUs such that a message from any c-RSU in the region can be disseminated to the more vehicles within the given budget constraint and delay bound. We first prove that the BCDP problem is NP-hard. Then we propose several algorithms to solve the BCDP problem. Simulation results show the heuristic algorithms can significantly improve the coverage range and reduce the total deployment cost, compared with other heuristic methods.
PMCID: PMC4299028  PMID: 25436656
roadside unit; facility placement; delay bound; vehicular sensor networks
24.  Effect of epigallocatechin-3-gallate on proliferation and phenotype maintenance in rabbit articular chondrocytes in vitro 
In autologous chondrocyte implantation (ACI) to restore defective cartilage, limited cell numbers and dedifferentiation of chondrocytes are the major difficulties. An alternative is the use of growth factors, but their high cost and potential for tumorigenesis are major obstacles. To ensure successful ACI therapy, it is important to find an effective substitute pro-chondrogenic agent. Epigallocatechin-3-gallate (EGCG), one of the green tea catechins, has been widely investigated in studies of interleukin-1β-induced chondrocytes. In the present study, the effects of EGCG on rabbit articular chondrocytes were investigated through the examination of cell proliferation, morphology, glycosaminoglycan synthesis and cartilage-specific gene expression. The results showed that EGCG could effectively promote chondrocyte growth and enhance the secretion and synthesis of the cartilage extracellular matrix by upregulating expression levels of aggrecan, collagen II and Sox9 genes. Expression of the collagen I gene was downregulated, which showed that EGCG effectively inhibited the dedifferentiation of chondrocytes. Hypertrophy, which may lead to chondrocyte ossification, was also undetectable in the EGCG groups. In conclusion, the recommended dose of EGCG was found to be in the range of 5 to 20 μM, with the most marked response observed with 10 μM. The present study may provide a basis for the development of a novel agent as a substitute for growth factors in the treatment of articular cartilage defects.
PMCID: PMC4247298  PMID: 25452805
epigallocatechin-3-gallate; pro-chondrogenic agent; chondrocyte; rabbit articular cartilage; dedifferentiation
25.  Concurrent MEK2 mutation and BRAF amplification confer resistance to BRAF and MEK inhibitors in melanoma 
Cell reports  2013;4(6):1090-1099.
Although BRAF and MEK inhibitors have proven clinical benefits in melanoma, most patients develop resistance. We report a de novo MEK2-Q60P mutation and BRAF gain in a melanoma from a patient who progressed on the MEK inhibitor trametinib and did not respond to the BRAF inhibitor dabrafenib. We also identified the same MEK2-Q60P mutation along with BRAF amplification in a xenograft tumor derived from a second melanoma patient resistant to the combination of dabrafenib and trametinib. Melanoma cells chronically exposed to trametinib acquired concurrent MEK2-Q60P mutation and BRAF-V600E amplification, which conferred resistance to MEK and BRAF inhibitors. The resistant cells had sustained MAPK activation and persistent phosphorylation of S6K. A triple combination of dabrafenib, trametinib, and the PI3K/mTOR inhibitor GSK2126458 led to sustained tumor growth inhibition. Hence, concurrent genetic events that sustain MAPK signaling can underlie resistance to both BRAF and MEK inhibitors, requiring novel therapeutic strategies to overcome it.
PMCID: PMC3956616  PMID: 24055054

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