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1.  MicroRNA-195 plays a tumor-suppressor role in human glioblastoma cells by targeting signaling pathways involved in cellular proliferation and invasion 
Neuro-Oncology  2012;14(3):278-287.
Accumulating evidence has implicated the deregluation of miRNAs in tumorigenesis. Previous studies have reported that microRNA-195 (miR-195) is markedly down-regulated in human glioblastoma cells, compared with normal brain tissue, but the biological role of miR-195 in glioblastoma development is currently unknown. In this study, we define a tumor-suppressor role for miR-195 in human glioblastoma cells. Over-expression of miR-195 in glioblastoma cell lines robustly arrested cell cycle progression and significantly repressed cellular invasion. We identified E2F3 and CCND3 as functional downstream targets of miR-195 in glioblastoma cells. Through knockdown studies, we demonstrated that E2F3 was the dominant effector of miR-195-mediated cell cycle arrest and that CCND3 was a key mediator of miR-195–induced inhibition of glioblastoma cell invasion. Furthermore, we showed that p27Kip1 was an important regulator downstream of CCND3 and that the accumulation of p27Kip1 in the cytoplasm might be responsible for the miR-195–mediated cell invasion inhibition in glioblastoma cells. This work provides evidence for the initial mechanism by which miR-195 negatively regulates both the proliferation and invasion of glioblastoma cells, suggesting that the down-regulation of miR-195 might contribute to the malignant transformation of glioblastoma cells and could be a molecular signature associated with glioblastoma progression.
doi:10.1093/neuonc/nor216
PMCID: PMC3280801  PMID: 22217655
glioblastoma; invasion; microRNA-195; proliferation; tumor-suppressor
2.  Identification of Differential Expression Genes in Leaves of Rice (Oryza sativa L.) in Response to Heat Stress by cDNA-AFLP Analysis 
BioMed Research International  2013;2013:576189.
High temperature impedes the growth and productivity of various crop species. To date, rice (Oryza sativa L.) has not been exploited to understand the molecular basis of its abnormally high level of temperature tolerance. To identify transcripts induced by heat stress, twenty-day-old rice seedlings of different rice cultivars suffering from heat stress were treated at different times, and differential gene expression analyses in leaves were performed by cDNA-AFLP and further verified by real-time RT-PCR. In aggregate, more than three thousand different fragments were indentified, and 49 fragments were selected for the sequence and differential expressed genes were classified functionally into different groups. 6 of 49 fragments were measured by real-time RT-PCR. In addition, the variations of three different polyamine contents in response to heat stress through high-performance liquid chromatography (HPLC) analysis were also performed. The results and their direct and indirect relationships to heat stress tolerance mechanism were discussed.
doi:10.1155/2013/576189
PMCID: PMC3590577
3.  Nucleotide-induced conformational changes of tetradecameric GroEL mapped by H/D exchange monitored by FT-ICR mass spectrometry 
Scientific Reports  2013;3:1247.
Here we employ hydrogen/deuterium exchange mass spectrometry (HDX-MS) to access E. coli chaperonin GroEL conformation. The ~800 kDa tetradecameric GroEL plays an essential role in the proper folding of many proteins. Previous studies of the structural dynamics of GroEL upon ATP binding have been inconsistent, showing either minimal or major allosteric changes. Our results, based on the native, non-mutated, protein under physiological conditions in solution demonstrate substantial changes in conformation and/or flexibility upon ATP binding. We capture the pivotal step in its functional cycle by use of a non-hydrolyzable ATP analog, ATPγS, to mimic the ATP-bound GroEL state. Comparison of HDX-MS results for apo GroEL and GroEL-ATPγS enables the characterization of the nucleotide-regulated conformational changes throughout the entire protein with high sequence resolution. The 14-mer GroEL complex is the largest protein assembly yet accessed by HDX-MS, with sequence resolution of segments of as few as five amino acids.
doi:10.1038/srep01247
PMCID: PMC3570780  PMID: 23409238
4.  Potential Theory for Directed Networks 
PLoS ONE  2013;8(2):e55437.
Uncovering factors underlying the network formation is a long-standing challenge for data mining and network analysis. In particular, the microscopic organizing principles of directed networks are less understood than those of undirected networks. This article proposes a hypothesis named potential theory, which assumes that every directed link corresponds to a decrease of a unit potential and subgraphs with definable potential values for all nodes are preferred. Combining the potential theory with the clustering and homophily mechanisms, it is deduced that the Bi-fan structure consisting of 4 nodes and 4 directed links is the most favored local structure in directed networks. Our hypothesis receives strongly positive supports from extensive experiments on 15 directed networks drawn from disparate fields, as indicated by the most accurate and robust performance of Bi-fan predictor within the link prediction framework. In summary, our main contribution is twofold: (i) We propose a new mechanism for the local organization of directed networks; (ii) We design the corresponding link prediction algorithm, which can not only testify our hypothesis, but also find out direct applications in missing link prediction and friendship recommendation.
doi:10.1371/journal.pone.0055437
PMCID: PMC3569429  PMID: 23408979
6.  trans-Dibromidotetra­kis­(pyridine-κN)ruthenium(II) 
The title complex, [RuBr2(C5H5N)4], contains two independent complex mol­ecules in each of which the RuII atom is located on a site of 222 symmetry and has a distorted octa­hedral coordination geometry with four pyridine N atoms and two Br atoms. The Br aroms are trans-disposed as a result of symmetry.
doi:10.1107/S1600536813000871
PMCID: PMC3569168  PMID: 23424402
7.  Migration of gastric cancer cells in response to lysophosphatidic acid is mediated by LPA receptor 2 
Oncology Letters  2013;5(3):1048-1052.
Lysophosphatidic acid (LPA), a natural phospholipid, is able to modulate diverse cellular responses through LPA receptors (LPARs). Several studies have reported that LPAR2 gene expression is increased in a variety of cancer cells, suggesting that LPAR2 is involved in gastric cancer. The present study investigated the expression profiles of the LPAR and involvement of the receptor subtypes in the LPA-induced migration of gastric cancer cells using cell migration assays, RNA interference, quantitative real-time PCR and western blotting. LPAR2 was observed to be highly expressed in SGC-7901 cells, a human gastric cancer cell line, while LPAR1 and LPAR3 were not. Transient transfection with LPAR2 siRNA was observed to reduce LPAR2 mRNA in SGC-7901 cells and eliminate the LPA-induced cell migration. It was also observed that LPA-induced SGC-7901 cell migration was inhibited by the inhibitor for Gq/11 protein and p38. The results suggest that the LPAR2/Gq/11/p38 pathway regulates LPA-induced SGC-7901 cell migration. The present findings suggest that LPAR2 may be a potential target for the clinical treatment of gastric cancer.
doi:10.3892/ol.2013.1107
PMCID: PMC3576385  PMID: 23426604
lysophosphatidic acid receptor2 (LPAR2); Gq/11; cell migration; gastric cancer
8.  Cyclin D3 compensates for the loss of Cyclin D1 during ErbB2-induced mammary tumor initiation and progression 
Cancer research  2011;71(24):7513-7524.
Cyclin D1 regulates cell proliferation and is a candidate molecular target for breast cancer therapy. The current work addresses whether Cyclin D1 is indispensable for ErbB2-associated mammary tumor initiation and progression using a breast cancer model in which this cell cycle regulator can be genetically ablated prior to or after neoplastic transformation. Deficiency in Cyclin D1 delayed tumor onset but did not prevent the occurrence of mammary cancer in mice overexpressing wildtype ErbB2. The lack of Cyclin D1 was associated with a compensatory upregulation of Cyclin D3, which explains why the targeted downregulation of Cyclin D1 in established mammary tumors had no effect on cancer cell proliferation. Cyclin D1 and D3 are overexpressed in human breast cancer cell lines and primary invasive breast cancers, and Cyclin D3 frequently exceeded the expression of Cyclin D1 in ErbB2-positive cases. The simultaneous inhibition of both cyclins in mammary tumor cells reduced cancer cell proliferation in vitro and decreased the tumor burden in vivo. Collectively, the results of this study suggest that only the combined inhibition of Cyclin D1 and D3 might be a suitable strategy for breast cancer prevention and therapy.
doi:10.1158/0008-5472.CAN-11-1783
PMCID: PMC3242818  PMID: 22037875
Cyclin D; Gene Targeting; Tetracycline Transactivator; ErbB2; Mammary Gland Development; Breast Cancer
9.  DOCK8 is essential for T-cell survival and the maintenance of CD8+ T-cell memory 
European journal of immunology  2011;41(12):3423-3435.
Deficiency in the guanine nucleotide exchange factor DOCK8 causes a human immunodeficiency syndrome associated with recurrent sinopulmonary and viral infections. We have recently identified a DOCK8-deficient mouse strain, carrying an ethylnitrosourea-induced splice-site mutation that shows a failure to mature a humoral immune response due to the loss of germinal centre B cells. In this study we turned to T-cell immunity to investigate further the human immunodeficiency syndrome and its association with decreased peripheral CD4+ and CD8+ T cells. Characterisation of the DOCK8-deficient mouse revealed T-cell lymphopenia, with increased T-cell turnover and decreased survival. Egress of mature CD4+ thymocytes was reduced with increased migration of these cells to the chemokine CXCL12. However, despite the two-fold reduction in peripheral naïve T cells, the DOCK8-deficient mice generated a normal primary CD8+ immune response and were able to survive acute influenza virus infection. The limiting effect of DOCK8 was in the normal survival of CD8+ memory T cells after infection. These findings help to explain why DOCK8-deficient patients are susceptible to recurrent infections and provide new insights into how T-cell memory is sustained.
doi:10.1002/eji.201141759
PMCID: PMC3517112  PMID: 21969276
Human; Rodent; Immunodeficiency; T cells; Memory
10.  Hyperimmunoglobulin E Syndromes in Pediatrics 
Current Opinion in Pediatrics  2011;23(6):653-658.
PURPOSE OF REVIEW
The hyper-IgE syndromes (HIES) are primary immunodeficiencies (PID) characterized by eczema, sinopulmonary infections, and elevated serum IgE. This review discusses the clinical similarities and differences between the autosomal dominant (AD-HIES) and autosomal recessive (AR-HIES) forms of this disease, as well as their causative genetic and pathophysiological mechanisms.
RECENT FINDINGS
Over the past four years, three genetic defects have been identified in HIES. Mutations in STAT3 are associated with AD-HIES, whereas mutations in DOCK8, or rarely TYK2, are associated with AR-HIES. Recent work has confirmed that measuring T helper 17 cell numbers can help predict STAT3 mutations. In AR-HIES, loss of DOCK8 expression was found to impair T cell expansion and durable specific antibody production by B cells. These factors probably contribute to the viral skin and other infectious susceptibilities, severe allergies, and high risk of malignancies that define this disorder.
SUMMARY
Establishing the molecular diagnosis of HIES is important for optimal patient management. Infections in AD-HIES are usually well controlled by antibiotics. By contrast, the viral infections in AR-HIES are difficult to manage. Their higher mortality and progressive course emphasizes the need to identify AR-HIES patients early, for consideration of potentially curative hematopoietic cell transplantation.
doi:10.1097/MOP.0b013e32834c7f65
PMCID: PMC3294453  PMID: 21970826
hyper-IgE syndrome; STAT3; DOCK8; TYK2; cutaneous viral infection
11.  Association between Leukocyte and Metabolic Syndrome in Urban Han Chinese: A Longitudinal Cohort Study 
PLoS ONE  2012;7(11):e49875.
Background
Although cross-sectional studies have shown that leukocyte is linked with metabolic syndrome (MetS), few longitudinal or cohort studies have been used to confirm this relationship. We therefore conducted a large-scale health check-up longitudinal cohort in urban Chinese population from middle to upper socioeconomic strata to investigate and prove the association between the total leukocyte/its subtypes and MetS/its components (obesity, hyperglycemia, dyslipidemia, and hypertension).
Methods
A longitudinal cohort study was established in 2005 on individuals who were middle-to-upper class urban Chinese. Data used in this investigation was based on 6,513 participants who had at least three routine health check-ups over a period of six-year follow-up. Data analysis was conducted through generalized estimating equation (GEE) model.
Results
A total of 255 cases of MetS occurred over the six-year follow-up, leading to a total incidence density of 11.45 per 1,000 person-years (255/22279 person-years). The total leukocyte was markedly associated with MetS (RR = 2.66, 95%CI = 1.81–3.90], p<0.0001) and a dose-response existed. Similar trends can be found in monocytes, lymphocytes, and neutrophils compared with the total leukocyte. The total leukocyte, neutrophil, monocyte and eosinophil levels were strong and independent risk factors to obesity, total leukocyte and neutrophil to dyslipidemia and hyperglycemia, while neither total leukocyte nor its subtypes to hypertension.
Conclusion
Total leukocyte/its subtype were associated with MetS/its components (obesity, dyslipidemia and hyperglycemia), they might provide convenient and useful markers for further risk appraisal of MetS, and be the earlier biomarkers for predicting cardiovascular disease than the components of MetS.
doi:10.1371/journal.pone.0049875
PMCID: PMC3507923  PMID: 23209610
12.  Development of New Technologies for Stem Cell Research 
Since the 1960s, the stem cells have been extensively studied including embryonic stem cells, neural stem cells, bone marrow hematopoietic stem cells, and mesenchymal stem cells. In the recent years, several stem cells have been initially used in the treatment of diseases, such as in bone marrow transplant. At the same time, isolation and culture experimental technologies for stem cell research have been widely developed in recent years. In addition, molecular imaging technologies including optical molecular imaging, positron emission tomography, single-photon emission computed tomography, and computed tomography have been developed rapidly in recent the 10 years and have also been used in the research on disease mechanism and evaluation of treatment of disease related with stem cells. This paper will focus on recent typical isolation, culture, and observation techniques of stem cells followed by a concise introduction. Finally, the current challenges and the future applications of the new technologies in stem cells are given according to the understanding of the authors, and the paper is then concluded.
doi:10.1155/2012/741416
PMCID: PMC3518316  PMID: 23251081
13.  A salen-type trinuclear Zn2Gd complex 
In the trinuclear title complex, di-μ-acetato-1:2κ2 O:O′;2:3κ2 O:O′-bis­{μ-6,6′-dimeth­oxy-2,2′-[cyclo­hexane-1,2-diylbis(methanylyl­idene)]diphenolato}-1:2κ6 O 1,N,N′,O 1′:O 6,O 6′;2:3κ6 O 6,O 6′:O 1,N,N′,O 1′-2-gadolinium(III)-1,3-dizinc hexa­fluor­idophosphate methanol monosolvate monohydrate, [GdZn2(C22H24N2O4)2(CH3COO)2]PF6·CH3OH·H2O, the two ZnII ions are located in the inner N2O2 cavities of two 6,6′-dimeth­oxy-2,2′-[cyclo­hexane-1,2-diylbis(methanylyl­idene)]diphenolate (L) ligands. Both ZnII ions are five-coordinated by two O atoms and two N atoms from the L ligand and one O atom of an acetic acid mol­ecule, giving rise to a square-pyramidal geometry around the ZnII ions. The GdIII ion is nine-coordinated by four O atoms from the outer O2O2 sites of one ligand, and three O atoms from another ligand, in which there is one non-coordinating meth­oxy O atom. Two further O atom from different acetate ligands complete the nine-coordinate environment.
doi:10.1107/S160053681204634X
PMCID: PMC3588752  PMID: 23468717
14.  A rule-based algorithm for automatic bond type perception 
Assigning bond orders is a necessary and essential step for characterizing a chemical structure correctly in force field based simulations. Several methods have been developed to do this. They all have advantages but with limitations too. Here, an automatic algorithm for assigning chemical connectivity and bond order regardless of hydrogen for organic molecules is provided, and only three dimensional coordinates and element identities are needed for our algorithm. The algorithm uses hard rules, length rules and conjugation rules to fix the structures. The hard rules determine bond orders based on the basic chemical rules; the length rules determine bond order by the length between two atoms based on a set of predefined values for different bond types; the conjugation rules determine bond orders by using the length information derived from the previous rule, the bond angles and some small structural patterns. The algorithm is extensively evaluated in three datasets, and achieves good accuracy of predictions for all the datasets. Finally, the limitation and future improvement of the algorithm are discussed.
doi:10.1186/1758-2946-4-26
PMCID: PMC3557220  PMID: 23113939
Bond type perception; Bond order; Chemical bond; Molecular modeling
15.  Effects and Safety of Calcimimetics in End Stage Renal Disease Patients with Secondary Hyperparathyroidism: A Meta-Analysis 
PLoS ONE  2012;7(10):e48070.
Purpose
Secondary hyperparathyroidism (SHPT) is one of the most common abnormalities of mineral metabolism in patients with chronic kidney disease. We performed a meta-analysis to determine the effect and safety of cinacalcet in SHPT patients receiving dialysis.
Methods
The meta-analysis was performed to determine the effect and safety of cinacalcet in SHPT patients receiving dialysis by using the search terms ‘cinacalcet’ or ‘mimpara’ or ‘sensipar’ or ‘calcimimetic’ or ‘R586’ on MEDLINE and EMBASE (January 1990 to February 2012).
Results
Fifteen trials were included, all of which were performed between 2000 and 2011 enrolling a total of 3387 dialysis patients. Our study showed that calcimimetic agents effectively ameliorated iPTH levels(WMD, −294.36 pg/mL; 95% CI, −322.76 to −265.95, P<0.001) in SHPT patients and reduced serum calcium (WMD, −0.81 mg/dL; 95% CI, −0.89 to −0.72, P<0.001) and phosphorus disturbances(WMD, −0.29 mg/dL; 95% CI, −0.41 to −0.17, P<0.001). The percentage of patients in whom there was a 30% decrease in serum iPTH levels by the end of the dosing was higher in cinacalcet group than that in control group(OR = 10.75, 95% CI: 6.65–17.37, P<0.001). However, no significant difference was found in all-cause mortality and all adverse events between calcimimetics and control groups(OR = 0.86, 95% CI: 0.46–1.60, P = 0.630; OR = 1.30, 95% CI: 0.78–2.18, P = 0.320, respectively). Compared with the control therapy, there was a significant increase in the episodes of hypocalcemia (OR = 2.46, 95% CI: 1.58–3.82, P<0.001), nausea (OR = 2.45, 95% CI: 1.29–4.66, P = 0.006), vomiting(OR = 2.78, 95% CI: 2.14–3.62, P<0.001), diarrhea(OR = 1.51, 95% CI: 1.04–2.20, P = 0.030) and upper respiratory tract infection (OR = 1.79, 95% CI: 1.20–2.66, P = 0.004)in calcimimetics group.
Conclusions
Calcimimetic treatment effectively improved biochemical parameters of SHPT patients receiving dialysis without increasing all-cause mortality and all adverse events.
doi:10.1371/journal.pone.0048070
PMCID: PMC3485048  PMID: 23133549
16.  Cataract surgery and intraocular lens implantation in anterior megalophthalmos 
doi:10.3980/j.issn.2222-3959.2012.05.22
PMCID: PMC3484707  PMID: 23166881
17.  Double-Grating Displacement Structure for Improving the Light Extraction Efficiency of LEDs 
The Scientific World Journal  2012;2012:515468.
To improve the light extraction efficiency of light-emitting diodes (LEDs), grating patterns were etched on GaN and silver film surfaces. The grating-patterned surface etching enabled the establishment of an LED model with a double-grating displacement structure that is based on the surface plasmon resonance principle. A numerical simulation was conducted using the finite difference time domain method. The influence of different grating periods for GaN surface and silver film thickness on light extraction efficiency was analyzed. The light extraction efficiency of LEDs was highest when the grating period satisfied grating coupling conditions. The wavelength of the highest value was also close to the light wavelength of the medium. The plasmon resonance frequencies on both sides of the silver film were affected by silver film thickness. With increasing film thickness, plasmon resonance frequency tended toward the same value and light extraction efficiency reached its maximum. When the grating period for the GaN surface was 365 nm and the silver film thickness was 390 nm, light extraction efficiency reached a maximum of 55%.
doi:10.1100/2012/515468
PMCID: PMC3478720  PMID: 23118613
18.  Cajaninstilbene Acid Relaxes Rat Renal Arteries: Roles of Ca2+ Antagonism and Protein Kinase C-Dependent Mechanism 
PLoS ONE  2012;7(10):e47030.
Cajaninstilbene acid (CSA) is a major active component present in the leaves of Cajanus cajan (L.) Millsp. The present study explores the underlying cellular mechanisms for CSA-induced relaxation in rat renal arteries. Vascular reactivity was examined in arterial rings that were suspended in a Multi Myograph System and the expression of signaling proteins was assessed by Western blotting method. CSA (0.1–10 µM) produced relaxations in rings pre-contracted by phenylephrine, serotonin, 9, 11-dideoxy-9α, 11α-epoxymethanoprostaglandin F2α (U46619), and 60 mM KCl. CSA-induced relaxations did not show difference between genders and were unaffected by endothelium denudation, nor by treatment with NG-nitro-L-arginine methyl ester, indomethacin, ICI-182780, tetraethylammonium ion, BaCl2, glibenclamide, 4-aminopyridine or propranolol. CSA reduced contraction induced by CaCl2 (0.01–5 mM) in Ca2+-free 60 mM KCl solution and by 30 nM (−)-Bay K8644 in 15 mM KCl solution. CSA inhibited 60 mM KCl-induced Ca2+ influx in smooth muscle of renal arteries. In addition, CSA inhibited contraction evoked by phorbol 12-myristate 13-acetate (PMA, protein kinase C agonist) in Ca2+-free Krebs solution. Moreover, CSA reduced the U46619- and PMA-induced phosphorylation of myosin light chain (MLC) at Ser19 and myosin phosphatase target subunit 1 (MYPT1) at Thr853 which was associated with vasoconstriction. CSA also lowered the phosphorylation of protein kinase C (PKCδ) at Thr505. In summary, the present results suggest that CSA relaxes renal arteries in vitro via multiple cellular mechanisms involving partial inhibition of calcium entry via nifedipine-sensitive calcium channels, protein kinase C and Rho kinase.
doi:10.1371/journal.pone.0047030
PMCID: PMC3467215  PMID: 23056567
19.  Effect of SNPs on Creatine Kinase Structure and Function: Identifying Potential Molecular Mechanisms for Possible Creatine Kinase Deficiency Diseases 
PLoS ONE  2012;7(9):e45949.
Single-nucleotide polymorphisms (SNPs) are common genetic material changes that often occur naturally. SNPs can cause amino acid replacements that may lead to severe diseases, such as the well-known sickle-cell anemia. We constructed eight SNP mutants of human brain-type creatine kinase (CKB) based on bioinformatics predictions. The biochemical and biophysical characteristics of these SNP mutants were determined and compared to those of the wild-type creatine kinase to explore the potential molecular mechanisms of possible creatine kinase SNP-induced diseases. While the reactivation of six SNP mutants after heat shock dropped more than 45%, only three of them showed notable increases in ANS fluorescence intensity and decreases in catalytic efficiency. Among them, H26Y and P36T bind substrates as well as the wild-type form does, but the melting temperatures (Tm) dropped below body temperature, while the T59I mutant exhibited decreased catalytic activity that was most likely due to the much reduced binding affinity of this mutant for substrates. These findings indicate that SNPs such as H26Y, P36T and T59I have the potential to induce genetic diseases by different mechanisms.
doi:10.1371/journal.pone.0045949
PMCID: PMC3457962  PMID: 23049898
20.  Epitope Mapping of a 95 kDa Antigen in Complex with Antibody by Solution-Phase Amide Backbone H/D Exchange Monitored by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry 
Analytical chemistry  2011;83(18):7129-7136.
The epitopes of a homohexameric food allergen protein, cashew Ana o 2, identified by two monoclonal antibodies, 2B5 and 1F5, were mapped by solution-phase amide backbone H/D exchange (HDX) coupled with FT-ICR MS and the results compared to previous mapping by immunological and mutational analyses. Antibody 2B5 defines a conformational epitope and 1F5 defines a linear epitope. Intact murine IgG antibodies were incubated with recombinant Ana o 2 (rAna o 2) to form antigen:monoclonal antibody (Ag-mAb) complexes. MAb-complexed and uncomplexed (free) rAna o 2 were then subjected to HDX. HDX instrumentation and automation were optimized to achieve high sequence coverage by protease XIII digestion. The regions protected from H/D exchange upon antibody binding overlap and thus confirm the previously identified epitope-bearing segments: the first extension of HDX monitored by mass spectrometry to a full-length antigen-antibody complex in solution.
doi:10.1021/ac201501z
PMCID: PMC3173601  PMID: 21861454
Hydrogen/Deterium Exchange; Allergen; Cashew; FT-ICR; FTMS
21.  Vaccinia virus-mediated intra-tumoral expression of matrix metalloproteinase 9 enhances oncolysis of PC-3 xenograft tumors 
BMC Cancer  2012;12:366.
Background
Oncolytic viruses, including vaccinia virus (VACV), are a promising alternative to classical mono-cancer treatment methods such as surgery, chemo- or radiotherapy. However, combined therapeutic modalities may be more effective than mono-therapies. In this study, we enhanced the effectiveness of oncolytic virotherapy by matrix metalloproteinase (MMP-9)-mediated degradation of proteins of the tumoral extracellular matrix (ECM), leading to increased viral distribution within the tumors.
Methods
For this study, the oncolytic vaccinia virus GLV-1h255, containing the mmp-9 gene, was constructed and used to treat PC-3 tumor-bearing mice, achieving an intra-tumoral over-expression of MMP-9. The intra-tumoral MMP-9 content was quantified by immunohistochemistry in tumor sections. Therapeutic efficacy of GLV-1h255 was evaluated by monitoring tumor growth kinetics and intra-tumoral virus titers. Microenvironmental changes mediated by the intra-tumoral MMP-9 over-expression were investigated by microscopic quantification of the collagen IV content, the blood vessel density (BVD) and the analysis of lymph node metastasis formation.
Results
GLV-1h255-treatment of PC-3 tumors led to a significant over-expression of intra-tumoral MMP-9, accompanied by a marked decrease in collagen IV content in infected tumor areas, when compared to GLV-1h68-infected tumor areas. This led to considerably elevated virus titers in GLV-1h255 infected tumors, and to enhanced tumor regression. The analysis of the BVD, as well as the lumbar and renal lymph node volumes, revealed lower BVD and significantly smaller lymph nodes in both GLV-1h68- and GLV-1h255- injected mice compared to those injected with PBS, indicating that MMP-9 over-expression does not alter the metastasis-reducing effect of oncolytic VACV.
Conclusions
Taken together, these results indicate that a GLV-1h255-mediated intra-tumoral over-expression of MMP-9 leads to a degradation of collagen IV, facilitating intra-tumoral viral dissemination, and resulting in accelerated tumor regression. We propose that approaches which enhance the oncolytic effect by increasing the intra-tumoral viral load, may be an effective way to improve therapeutic outcome.
doi:10.1186/1471-2407-12-366
PMCID: PMC3495867  PMID: 22917220
22.  Imaging Characteristics, Tissue Distribution, and Spread of a Novel Oncolytic Vaccinia Virus Carrying the Human Sodium Iodide Symporter 
PLoS ONE  2012;7(8):e41647.
Introduction
Oncolytic viruses show promise for treating cancer. However, to assess therapy and potential toxicity, a noninvasive imaging modality is needed. This study aims to determine the in vivo biodistribution, and imaging and timing characteristics of a vaccinia virus, GLV-1h153, encoding the human sodium iodide symporter (hNIS.
Methods
GLV-1h153 was modified from GLV-1h68 to encode the hNIS gene. Timing of cellular uptake of radioiodide 131I in human pancreatic carcinoma cells PANC-1 was assessed using radiouptake assays. Viral biodistribution was determined in nude mice bearing PANC-1 xenografts, and infection in tumors confirmed histologically and optically via Green Fluorescent Protein (GFP) and bioluminescence. Timing characteristics of enhanced radiouptake in xenografts were assessed via 124I-positron emission tomography (PET). Detection of systemic administration of virus was investigated with both 124I-PET and 99m-technecium gamma-scintigraphy.
Results
GLV-1h153 successfully facilitated time-dependent intracellular uptake of 131I in PANC-1 cells with a maximum uptake at 24 hours postinfection (P<0.05). In vivo, biodistribution profiles revealed persistence of virus in tumors 5 weeks postinjection at 109 plaque-forming unit (PFU)/gm tissue, with the virus mainly cleared from all other major organs. Tumor infection by GLV-1h153 was confirmed via optical imaging and histology. GLV-1h153 facilitated imaging virus replication in tumors via PET even at 8 hours post radiotracer injection, with a mean %ID/gm of 3.82±0.46 (P<0.05) 2 days after intratumoral administration of virus, confirmed via tissue radiouptake assays. One week post systemic administration, GLV-1h153-infected tumors were detected via 124I-PET and 99m-technecium-scintigraphy.
Conclusion
GLV-1h153 is a promising oncolytic agent against pancreatic cancer with a promising biosafety profile. GLV-1h153 facilitated time-dependent hNIS-specific radiouptake in pancreatic cancer cells, facilitating detection by PET with both intratumoral and systemic administration. Therefore, GLV-1h153 is a promising candidate for the noninvasive imaging of virotherapy and warrants further study into longterm monitoring of virotherapy and potential radiocombination therapies with this treatment and imaging modality.
doi:10.1371/journal.pone.0041647
PMCID: PMC3422353  PMID: 22912675
23.  Dietary Pattern and Its Association with the Prevalence of Obesity and Related Cardiometabolic Risk Factors among Chinese Children 
PLoS ONE  2012;7(8):e43183.
Background
The association of dietary pattern with chronic diseases has been investigated widely in western countries. However, information is quite limited among children in China. Our study is aimed to identify the dietary patterns of Chinese children and examine their association with obesity and related cardiometabolic risk factors.
Methods
A total of 5267 children were selected using multistage random sampling from 30 primary schools of 5 provincial capital cities in China. Dietary intake was derived from 24 hour dietary recall for three consecutive days. Anthropometric measurements, glucose and lipid profiles were obtained. Factor analysis combined with cluster analysis was used for identifying major dietary patterns. The associations of dietary patterns with obesity and related cardiometabolic risk factors were examined by logistic regression analysis.
Results
Three mutually exclusive dietary patterns were identified, which were labeled as the healthy dietary pattern, the transitive dietary pattern, and the Western dietary pattern. Compared with children of the healthy dietary pattern, the multiple-adjusted odds ratios (95% confidence interval (CI)) of obesity were 1.11 (0.89–1.38) for children with the transitive dietary pattern and 1.80 (1.15–2.81) for children with the Western dietary pattern, which was 1.31 (95%CI 1.09–1.56) and 1.71 (95%CI: 1.13–2.56), respectively, for abdominal obesity. The Western dietary pattern was associated with significantly higher concentrations of low-density lipoprotein cholesterol (P<.001), triglycerides (P<.001), systolic blood pressure (P = 0.0435) and fasting glucose (P = 0.0082) and a lower concentration of high-density lipoprotein cholesterol (P = 0.0023), as compared with the healthy dietary pattern.
Conclusions
The Western dietary pattern characterized by red meat, eggs, refined grain and products, was positively associated with odds of obesity, the levels of plasma glucose, low-density lipoprotein cholesterol and triglycerides, and was inversely associated with the level of high-density lipoprotein cholesterol.
doi:10.1371/journal.pone.0043183
PMCID: PMC3419173  PMID: 22905228
24.  Legumes Can Increase Cadmium Contamination in Neighboring Crops 
PLoS ONE  2012;7(8):e42944.
Legumes are widely used in many cropping systems because they share their nitrogen fixation products and phosphorus mobilization activities with their neighbors. In the current study, however, we showed that co-cultivation with legumes increased cadmium (Cd) contamination in the adjacent crops. Both field and mesocosm experiments indicated that legumes increased Cd levels in edible parts and shoots of four neighboring crops and five maize varieties tested, regardless of the Cd levels in the soil. This enhanced Cd accumulation in crops was attributed to root interactions that alter the rhizosphere environment. Co-cultivation with legumes reduced soil pH, which somewhat increased the exchangeable forms of Cd. Our results have demonstrated the inevitable increases in Cd levels of crops as a direct result of co-cultivation with legumes even under situations when these levels are below the permissible threshold. With this new revelation, we need to consider carefully the current cropping systems involving legumes and perhaps to re-design the current and future cropping systems in view of avoiding food contamination by Cd.
doi:10.1371/journal.pone.0042944
PMCID: PMC3419222  PMID: 22905189
25.  Sparse Reconstruction for Bioluminescence Tomography Based on the Semigreedy Method 
Bioluminescence tomography (BLT) is a molecular imaging modality which can three-dimensionally resolve the molecular processes in small animals in vivo. The ill-posedness nature of BLT problem makes its reconstruction bears nonunique solution and is sensitive to noise. In this paper, we proposed a sparse BLT reconstruction algorithm based on semigreedy method. To reduce the ill-posedness and computational cost, the optimal permissible source region was automatically chosen by using an iterative search tree. The proposed method obtained fast and stable source reconstruction from the whole body and imposed constraint without using a regularization penalty term. Numerical simulations on a mouse atlas, and in vivo mouse experiments were conducted to validate the effectiveness and potential of the method.
doi:10.1155/2012/494808
PMCID: PMC3426305  PMID: 22927887

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