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1.  Perturbation of Auxin Homeostasis by Overexpression of Wild-Type IAA15 Results in Impaired Stem Cell Differentiation and Gravitropism in Roots 
PLoS ONE  2013;8(3):e58103.
Aux/IAAs interact with auxin response factors (ARFs) to repress their transcriptional activity in the auxin signaling pathway. Previous studies have focused on gain-of-function mutations of domain II and little is known about whether the expression level of wild-type Aux/IAAs can modulate auxin homeostasis. Here we examined the perturbation of auxin homeostasis by ectopic expression of wild-type IAA15. Root gravitropism and stem cell differentiation were also analyzed. The transgenic lines were less sensitive to exogenous auxin and exhibited low-auxin phenotypes including failures in gravity response and defects in stem cell differentiation. Overexpression lines also showed an increase in auxin concentration and reduced polar auxin transport. These results demonstrate that an alteration in the expression of wild-type IAA15 can disrupt auxin homeostasis.
doi:10.1371/journal.pone.0058103
PMCID: PMC3589423  PMID: 23472140
2.  Application of Back Propagation Artificial Neural Network on Genetic Variants in Adiponectin ADIPOQ, Peroxisome Proliferator-Activated Receptor-γ, and Retinoid X Receptor-α Genes and Type 2 Diabetes Risk in a Chinese Han Population 
Abstract
Aims
Our study was designed to explore the applied characteristics of the back propagation artificial neural network (BPANN) on studying the genetic variants in adipnectin ADIPOQ, peroxisome proliferator-activated receptor (PPAR)-γ, and retinoid X receptor-α (RXR-α) genes and type 2 diabetes mellitus (T2DM) risks in a Chinese Han population.
Subjects and Methods
We used BPANN as the fitting model based on data gathered from T2DM patients (n=913) and normal controls (n=1,001). The mean impact value (MIV) for each input variables were calculated, and the sequence of the factors according to their absolute MIVs was sorted.
Results
The results from BPANN were compared with multiple logistic regression analysis, and the generalized multifactor dimensionality reduction (GMDR) method was used to calculate the joint effects of ADIPOQ, PPAR-γ, and RXR-α genes. By BPANN analysis, the sequence according to the importance of the T2DM risk factors was in the order of serum adiponectin level, rs3856806, rs7649121, hypertension, rs3821799, rs17827276, rs12495941, rs4240711, age, rs16861194, waist circumference, rs2241767, rs2920502, rs1063539, alcohol drinking, smoking, hyperlipoproteinemia, gender, rs3132291, T2DM family history, rs4842194, rs822394, rs1801282, rs1045570, rs16861205, rs6537944, body mass index, rs266729, and rs1801282. However, compared with multiple logistic regression analysis, only 11 factors were statistically significant. After overweight and obesity were taken as environment adjustment factors into the analysis, model A2 B4 C5 C6 C8 (rs3856806, rs4240711, rs7649121, rs3821799, rs12495941) was the best model (coefficient of variation consistency=10/10, P=0.0107) in the GMDR method.
Conclusions
These results suggested the interactions of ADIPOQ, PPAR-γ, and RXR-α genes might play a role in susceptibility to T2DM. BPANN could be used to analyze the risk factors of diseases and provide more complicated relationships between inputs and outputs.
doi:10.1089/dia.2011.0071
PMCID: PMC3284696  PMID: 22023374
3.  Functional study of an aberrant splicing variant of the human luteinizing hormone (LH) receptor 
Molecular Human Reproduction  2011;18(3):129-135.
The luteinizing hormone receptor (LHR) is a member of a subfamily of G protein-coupled receptors that is characterized by its alternative splicing. In a previous study, we identified a splice site mutation of intron 6 (IVS6-3C>A) in a patient suffering from Leydig cell hypoplasia, which leads to aberrant splicing of LHR mRNA. In vitro expression analysis confirmed that this mutation results in the skipping of exon 7 in the mature mRNA of the LHR gene. In this study, we determined the impact of IVS6-3C>A on the RNA secondary structure and function of LHR-Del7. The three-dimensional structure of the leucine-rich repeats in LHR was predicted by molecular modeling. Radioactive ligand-binding assays verified that LHR-Del7 has no binding affinity for hCG. Furthermore, we detected negligible cAMP production in cells transfected with LHR-Del7. Cells co-expressing LHR-WT and LHR-Del7 were able to generate cAMP in response to hCG, but there was no significant difference between cells transfected with LHR-WT/vector and LHR-WT/LHR-Del7, although the variant was able to localize to cell surface, similar to wild-type receptor. These results indicated that LHR-Del7 does not have a dominant negative effect on LHR-WT cell surface expression, and although the pathological splicing variant LHR-Del7 was able to localize to cell membranes it failed to bind hCG and had no effect on wild-type LHR.
doi:10.1093/molehr/gar065
PMCID: PMC3292396  PMID: 22002533
function study; splicing variant; LHR
4.  Multiple endocrine neoplasia type 1 with upper gastrointestinal hemorrhage and perforation: A case report and review 
Multiple endocrine neoplasia type 1 (MEN1) is a rare hereditary syndrome known to predispose subjects to endocrine neoplasms in a variety of tissues such as the parathyroid glands, pituitary gland, pancreas and gastrointestinal tract. We herein report a patient with a past history of pituitary adenoma, presenting with symptoms of chronic diarrhea for nearly one year and a sudden upper gastrointestinal hemorrhage as well as perforation without signs. Nodules in the duodenum and in the uncinate process and tail of pancreas and enlargement of the parathyroid glands were detected on preoperative imaging. Gastroscopy revealed significant ulceration and esophageal reflux diseases. The patient underwent subtotal parathyroidectomy and autotransplantation, pylorus-preserving pancreaticoduodenectomy and pancreatic tail resection and recovered well. The results observed in our patient suggest that perforation and bleeding of intestine might be symptoms of Zollinger-Ellison Syndrome in patients with MEN1.
doi:10.3748/wjg.v19.i8.1322
PMCID: PMC3587492  PMID: 23482249
Pituitary adenoma; Hyperparathyroidism; Gastrinoma; Gastrointestinal hemorrhage; Perforation
5.  A novel pulsed drug-delivery system: polyelectrolyte layer-by-layer coating of chitosan–alginate microgels 
Purpose
The aim of this report was to introduce a novel “core-membrane” microgel drug-delivery device for spontaneously pulsed release without any external trigger.
Methods
The microgel core was prepared with alginate and chitosan. The semipermeable membrane outside the microgel was made of polyelectrolytes including polycation poly(allylamine hydrochloride) and sodium polystyrene sulfonate. The drug release of this novel system was governed by the swelling pressure of the core and the rupture of the outer membrane.
Results
The size of the core-membrane microgel drug-delivery device was 452.90 ± 2.71 μm. The surface charge depended on the layer-by-layer coating of polyelectrolytes, with zeta potential of 38.6 ± 1.4 mV. The confocal microscope exhibited the layer-by-layer outer membrane and inner core. The in vitro release profile showed that the content release remained low during the first 2.67 hours. After this lag time, the cumulative release increased to 80% in the next 0.95 hours, which suggested a pulsed drug release. The in vivo drug release in mice showed that the outer membrane was ruptured at approximately 3 to 4 hours, as drug was explosively released.
Conclusion
These data suggest that the encapsulated substance in the core-membrane microgel delivery device can achieve a massive drug release after outer membrane rupture. This device was an effective system for pulsed drug delivery.
doi:10.2147/IJN.S38144
PMCID: PMC3592514  PMID: 23486565
polyelectrolyte; chitosan-alginate; microgels; layer-by-layer; pulsed drug delivery
6.  Application of Massively Parallel Sequencing to Genetic Diagnosis in Multiplex Families with Idiopathic Sensorineural Hearing Impairment 
PLoS ONE  2013;8(2):e57369.
Despite the clinical utility of genetic diagnosis to address idiopathic sensorineural hearing impairment (SNHI), the current strategy for screening mutations via Sanger sequencing suffers from the limitation that only a limited number of DNA fragments associated with common deafness mutations can be genotyped. Consequently, a definitive genetic diagnosis cannot be achieved in many families with discernible family history. To investigate the diagnostic utility of massively parallel sequencing (MPS), we applied the MPS technique to 12 multiplex families with idiopathic SNHI in which common deafness mutations had previously been ruled out. NimbleGen sequence capture array was designed to target all protein coding sequences (CDSs) and 100 bp of the flanking sequence of 80 common deafness genes. We performed MPS on the Illumina HiSeq2000, and applied BWA, SAMtools, Picard, GATK, Variant Tools, ANNOVAR, and IGV for bioinformatics analyses. Initial data filtering with allele frequencies (<5% in the 1000 Genomes Project and 5400 NHLBI exomes) and PolyPhen2/SIFT scores (>0.95) prioritized 5 indels (insertions/deletions) and 36 missense variants in the 12 multiplex families. After further validation by Sanger sequencing, segregation pattern, and evolutionary conservation of amino acid residues, we identified 4 variants in 4 different genes, which might lead to SNHI in 4 families compatible with autosomal dominant inheritance. These included GJB2 p.R75Q, MYO7A p.T381M, KCNQ4 p.S680F, and MYH9 p.E1256K. Among them, KCNQ4 p.S680F and MYH9 p.E1256K were novel. In conclusion, MPS allows genetic diagnosis in multiplex families with idiopathic SNHI by detecting mutations in relatively uncommon deafness genes.
doi:10.1371/journal.pone.0057369
PMCID: PMC3579845  PMID: 23451214
7.  Surface Plasmon Resonance Sensor Based on Polymer Photonic Crystal Fibers with Metal Nanolayers 
Sensors (Basel, Switzerland)  2013;13(1):956-965.
A large-mode-area polymer photonic crystal fiber made of polymethyl methacrylate with the cladding having only one layer of air holes near the edge of the fiber is designed and proposed to be used in surface plasmon resonance sensors. In such sensor, a nanoscale metal film and analyte can be deposited on the outer side of the fiber instead of coating or filling in the holes of the conventional PCF, which make the real time detection with high sensitivity easily to realize. Moreover, it is relatively stable to changes of the amount and the diameter of air holes, which is very beneficial for sensor fabrication and sensing applications. Numerical simulation results show that under the conditions of the similar spectral and intensity sensitivity of 8.3 × 10−5–9.4 × 10−5 RIU, the confinement loss can be increased dramatically.
doi:10.3390/s130100956
PMCID: PMC3574714  PMID: 23322099
polymer photonic crystal fiber; surface plasmon resonance sensor
8.  Strand-specific RNA-seq reveals widespread occurrence of novel cis-natural antisense transcripts in rice 
BMC Genomics  2012;13:721.
Background
Cis-natural antisense transcripts (cis-NATs) are RNAs transcribed from the antisense strand of a gene locus, and are complementary to the RNA transcribed from the sense strand. Common techniques including microarray approach and analysis of transcriptome databases are the major ways to globally identify cis-NATs in various eukaryotic organisms. Genome-wide in silico analysis has identified a large number of cis-NATs that may generate endogenous short interfering RNAs (nat-siRNAs), which participate in important biogenesis mechanisms for transcriptional and post-transcriptional regulation in rice. However, the transcriptomes are yet to be deeply sequenced to comprehensively investigate cis-NATs.
Results
We applied high-throughput strand-specific complementary DNA sequencing technology (ssRNA-seq) to deeply sequence mRNA for assessing sense and antisense transcripts that were derived under salt, drought and cold stresses, and normal conditions, in the model plant rice (Oryza sativa). Combined with RAP-DB genome annotation (the Rice Annotation Project Database build-5 data set), 76,013 transcripts corresponding to 45,844 unique gene loci were assembled, in which 4873 gene loci were newly identified. Of 3819 putative rice cis-NATs, 2292 were detected as expressed and giving rise to small RNAs from their overlapping regions through integrated analysis of ssRNA-seq data and small RNA data. Among them, 503 cis-NATs seemed to be associated with specific conditions. The deep sequence data from isolated epidermal cells of rice seedlings further showed that 54.0% of cis-NATs were expressed simultaneously in a population of homogenous cells. Nearly 9.7% of rice transcripts were involved in one-to-one or many-to-many cis-NATs formation. Furthermore, only 17.4-34.7% of 223 many-to-many cis-NAT groups were all expressed and generated nat-siRNAs, indicating that only some cis-NAT groups may be involved in complex regulatory networks.
Conclusions
Our study profiles an abundance of cis-NATs and nat-siRNAs in rice. These data are valuable for gaining insight into the complex function of the rice transcriptome.
doi:10.1186/1471-2164-13-721
PMCID: PMC3549290  PMID: 23259405
Oryza sativa; Cis-NATs; Nat-siRNAs; SsRNA-seq; Transcriptome
9.  Bayesian decision analysis for choosing between diagnostic/prognostic prediction procedures 
Statistics and its interface  2011;4(1):27-36.
New diagnostic procedures and prognostic markers are continually being developed for a wide range of medical complaints. Medical institutions are therefore regularly faced with the decision as to whether to replace an existing procedure with a new one. The decision to adopt a new method is primarily based on diagnostic/predictive accuracy and cost-effectiveness, but this trade-off is not usually considered in a formal decision-theoretic way. The decision process for diagnostic procedures is complicated by the fact that diagnostic decisions are typically based on thresholding one or more continuous variables. Therefore, a formal decision process should account for uncertainty in the optimal threshold value for each diagnostic procedure. We here propose a Bayesian decision approach based on maximizing expected utility (incorporating accuracy and costs) with respect to diagnostic procedure and threshold level simultaneously. The Bayesian decision approach is illustrated via an application comparing the utility of different bone mineral density (BMD) measurements for determining the need for preventative treatment of osteoporotic hip fracture in elderly patients.
PMCID: PMC3520495  PMID: 23243483
Bayesian decision analysis; decision theory; diagnostic methods
10.  Evaluating the Improvement in Diagnostic Utility from Adding New Predictors 
Summary
Multiple diagnostic tests and risk factors are commonly available for many diseases. This information can be either redundant or complimentary. Combinations of these tests and risk factors may improve the diagnostic/predictive accuracy but also may unnecessarily increase complexity, risks, and/or costs. The improved accuracy gained by including additional variables can be evaluated by the increment of the area under (AUC) the receiver operating characteristic (ROC) curves with and without the new variable(s). In this paper, we derive a new test statistic to accurately and efficiently determine the statistical significance of this incremental AUC under a multivariate normality assumption. Our test links the difference in AUC to a quadratic form of a standardized mean shift in a unit of the inverse covariance matrix through a properly linear transformation of all diagnostic variables. The distribution of the estimator of the quadratic form is related to the multivariate Behrens-Fisher problem. We provide explicit mathematical solutions of the estimator and its approximate noncentral F-distribution, type I error rate, and sample size formula. We use simulation studies to prove that our new test maintains prespecified type I error rates as well as reasonable statistical power under practical sample sizes. We use data from the Study of Osteoporotic Fractures (SOF) as an application example to illustrate our method.
doi:10.1002/bimj.200900228
PMCID: PMC3517010  PMID: 20496347
Area under ROC curves; Behrens-Fisher problem; Noncentral F distribution; Receiver operating characteristic curve
11.  In vitro-In vivo Correlation: Perspectives on Model Development 
In vitro – in vivo correlation (IVIVC) allows prediction of the in vivo performance of a drug based on the in vitro drug release profiles. To develop an effective IVIVC, the physicochemical and biopharmaceutical properties of the drug as well as the physiological environment in the body must be taken into consideration. Key factors include drug solubility, pKa, drug permeability, octanol-water partition coefficient and pH of environment. In general, construction of an IVIVC involves three stages of mathematical manipulation: construct a functional relationship between input (in vitro dissolution) and output (in vivo dissolution); establish a structural relationship using data collected; parameterize the unknowns in the structural model. Some key mathematical relationships used in IVIVC development are presented. The establishment of an effective IVIVC has important implications in quality control and regulatory compliance.
doi:10.1016/j.ijpharm.2011.01.010
PMCID: PMC3099258  PMID: 21237256
12.  Amino Acid Position 11 of HLA-DRβ1 is a Major Determinant of Chromosome 6p Association with Ulcerative Colitis 
Genes and Immunity  2011;13(3):245-252.
The major histocompatibility complex (MHC) on chromosome 6p is an established risk locus for ulcerative colitis (UC) and Crohn’s disease (CD). We aimed to better define MHC association signals in UC and CD by combining data from dense single nucleotide polymorphism (SNP) genotyping and from imputation of classical HLA types, their constituent SNPs and corresponding amino acids in 562 UC, 611 CD, and 1,428 control subjects. Univariate and multivariate association analyses were performed, controlling for ancestry. In univariate analyses, absence of the rs9269955 C allele was strongly associated with risk for UC (P = 2.67×10−13). rs9269955 is a SNP in the codon for amino acid position 11 of HLA-DRβ1, located in the P6 pocket of the HLA-DR antigen binding cleft. This amino acid position was also the most significantly UC-associated amino acid in omnibus tests (P = 2.68×10−13). Multivariate modeling identified rs9269955-C and 13 other variants in best predicting UC versus control status. In contrast, there was only suggestive association evidence between the MHC and CD. Taken together, these data demonstrate that variation at HLA-DRβ1, amino acid 11 in the P6 pocket of the HLA-DR complex antigen binding cleft is a major determinant of chromosome 6p association with ulcerative colitis.
doi:10.1038/gene.2011.79
PMCID: PMC3341846  PMID: 22170232
inflammatory bowel disease genetics; major histocompatibility complex; ulcerative colitis
13.  Clinicopathological characteristics of patients with synchronous primary endometrial and ovarian cancers: A review of 43 cases 
Oncology Letters  2012;5(1):267-270.
Synchronous primary endometrial and ovarian cancers are uncommon. The purpose of this study was to evaluate the clinicopathological characteristics, treatment and prognosis of synchronous primary endometrial and ovarian cancers. The clinicopathological characteristics of 43 patients with synchronous primary endometrial and ovarian cancers in the Obstetrics and Gynecology Hospital of Fudan University between 1999 and 2009 were retrospectively reviewed. Our results revealed that the median age at the time of diagnosis was 51 years (range, 29–71). The common presenting symptoms were abnormal uterine bleeding (AUB, 65.12%), abdominal mass (25.58%), abdominal pain and abdominal fullness (39.53%). An elevated CA125 level was observed in the majority of patients (n=20, 76.9%). Endometrioid type accounted for 60.47% of uterine carcinomas and different pathological types, including serous adenocarcinoma, clear cell carcinoma, adenosquamous and acanthoadenocarcinoma, were also identified in synchronous primary endometrial and ovarian cancers. All patients underwent surgical intervention (hysterectomy and bilateral salpingo-oophorectomy with pelvic lymphadenectomy or debulking surgery). The 5-year survival rate was 86.05% and nine patients had recurrence (20.93%). The early stage group (FIGO stages I and II) had more favorable prognosis than the advanced stage group (FIGO stages III and IV; P<0.05). In conclusion, synchronous primary endometrial and ovarian cancers are different from either primary endometrial carcinoma or ovarian cancer and are usually identified at early stages with a good prognosis.
doi:10.3892/ol.2012.943
PMCID: PMC3525502  PMID: 23255933
synchronous primary cancers; endometrial cancer; ovarian cancer; prognosis
14.  In vivo role of nitric oxide in plant response to abiotic and biotic stress 
Plant Signaling & Behavior  2012;7(3):437-439.
Over the past few years, nitric oxide (NO) has emerged as an important regulator in many physiological events, especially in response to abiotic and biotic stress. However, the roles of NO were mostly derived from pharmacological studies or the mutants impaired NO synthesis unspecifically. In our recent study, we highlighted a novel strategy by expressing the rat neuronal NO synthase (nNOS) in Arabidopsis to explore the in vivo role of NO. Our results suggested that plants were able to perform well in the constitutive presence of nNOS, and provided a new class of plant experimental system with specific in vivo NO release. Furthermore, our findings also confirmed that the in vivo NO is essential for most of environmental abiotic stresses and disease resistance against pathogen infection. Proper level of NO may be necessary and beneficial, not only in plant response to the environmental abiotic stress, but also to biotic stress.
doi:10.4161/psb.19219
PMCID: PMC3443929  PMID: 22499209
abiotic and biotic stress; disease resistance; drought; in vivo; nitric oxide; nitric oxide synthase; salinity
15.  Gene expression profiling and endothelin in acute experimental pancreatitis 
AIM: To analyze gene expression profiles in an experimental pancreatitis and provide functional reversal of hypersensitivity with candidate gene endothelin-1 antagonists.
METHODS: Dibutyltin dichloride (DBTC) is a chemical used as a polyvinyl carbonate stabilizer/catalyzer, biocide in agriculture, antifouling agent in paint and fabric. DBTC induces an acute pancreatitis flare through generation of reactive oxygen species. Lewis-inbred rats received a single i.v. injection with either DBTC or vehicle. Spinal cord and dorsal root ganglia (DRG) were taken at the peak of inflammation and processed for transcriptional profiling with a cDNA microarray biased for rat brain-specific genes. In a second study, groups of animals with DBTC-induced pancreatitis were treated with endothelin (ET) receptor antagonists [ET-A (BQ123) and ET-B BQ788)]. Spontaneous pain related mechanical and thermal hypersensitivity were measured. Immunohistochemical analysis was performed using anti-ET-A and ET-B antibodies on sections from pancreatic tissues and DRG of the T10-12 spinal segments.
RESULTS: Animals developed acute pancreatic inflammation persisting 7-10 d as confirmed by pathological studies (edema in parenchyma, loss of pancreatic architecture and islets, infiltration of inflammatory cells, neutrophil and mononuclear cells, degeneration, vacuolization and necrosis of acinar cells) and the pain-related behaviors (cutaneous secondary mechanical and thermal hypersensitivity). Gene expression profile was different in the spinal cord from animals with pancreatitis compared to the vehicle control group. Over 260 up-regulated and 60 down-regulated unique genes could be classified into 8 functional gene families: circulatory/acute phase/immunomodulatory; extracellular matrix; structural; channel/receptor/transporter; signaling transduction; transcription/translation-related; antioxidants/chaperones/heat shock; pancreatic and other enzymes. ET-1 was among the 52 candidate genes up-regulated greater than 2-fold in animals with pancreatic inflammation and visceral pain-related behavior. Treatments with the ET-A (BQ123) and ET-B (BQ-788) antagonists revealed significant protection against inflammatory pain related mechanical and thermal hypersensitivity behaviors in animals with pancreatitis (P < 0.05). Open field spontaneous behavioral activity (at baseline, day 6 and 30 min after drug treatments (BQ123, BQ788) showed overall stable activity levels indicating that the drugs produced no undesirable effects on normal exploratory behaviors, except for a trend toward reduction of the active time and increase in resting time at the highest dose (300 μmol/L). Immunocytochemical localization revealed that expression of ET-A and ET-B receptors increased in DRG from animals with pancreatitis. Endothelin receptor localization was combined in dual staining with neuronal marker NeuN, and glia marker, glial fibrillary acidic protein. ET-A was expressed in the cell bodies and occasional nuclei of DRG neurons in naïve animals. However, phenotypic expression of ET-A receptor was greatly increased in neurons of all sizes in animals with pancreatitis. Similarly, ET-B receptor was localized in neurons and in the satellite glia, as well as in the Schwann cell glial myelin sheaths surrounding the axons passing through the DRG.
CONCLUSION: Endothelin-receptor antagonists protect against inflammatory pain responses without interfering with normal exploratory behaviors. Candidate genes can serve as future biomarkers for diagnosis and/or targeted gene therapy.
doi:10.3748/wjg.v18.i32.4257
PMCID: PMC3436040  PMID: 22969188
Gene expression; Endothelin receptors; Pancreatitis; Pain; Dibutyltin dichloride; Hypersensitivity; Hyperalgesia
16.  Identification of Protective Pneumococcal TH17 Antigens from the Soluble Fraction of a Killed Whole Cell Vaccine 
PLoS ONE  2012;7(8):e43445.
Mucosal or parenteral immunization with a killed unencapsulated pneumococcal whole cell antigen (WCA) with an adjuvant protects mice from colonization by a TH17 CD4+ cell-mediated mechanism. Using preparative SDS gels, we separated the soluble proteins that compose the WCA in order to identify fractions that were immunogenic and protective. We screened these fractions for their ability to stimulate IL-17A secretion from splenocytes obtained from mice immunized with WCA and adjuvant. We identified 12 proteins within the stimulatory fractions by mass spectrometry; these proteins were then cloned, recombinantly expressed and purified using an Escherichia coli expression system. The ability of these proteins to induce IL-17A secretion was then evaluated by stimulation of mouse splenocytes. Of the four most stimulatory proteins, three were protective in a mouse pneumococcal serotype 6B colonization model. This work thus describes a method for identifying immunogenic proteins from the soluble fraction of pneumococcus and shows that several of the proteins identified protect mice from colonization when used as mucosal vaccines. We propose that, by providing protection against pneumococcal colonization, one or more of these proteins may serve as components of a multivalent pneumococcal vaccine.
doi:10.1371/journal.pone.0043445
PMCID: PMC3419164  PMID: 22905267
17.  P2X7 signaling promotes microsphere embolism-triggered microglia activation by maintaining elevation of Fas ligand 
Background
The cerebral microvascular occlusion elicits microvascular injury which mimics the different degrees of stroke severity observed in patients, but the mechanisms underlying these embolic injuries are far from understood. The Fas ligand (FasL)-Fas system has been implicated in a number of pathogenic states. Here, we examined the contribution of microglia-derived FasL to brain inflammatory injury, with a focus on the potential to suppress the FasL increase by inhibition of the P2X7-FasL signaling with pharmacological or genetic approaches during ischemia.
Methods
The cerebral microvascular occlusion was induced by microsphere injection in experimental animals. Morphological changes in microglial cells were studied immunohistochemically. The biochemical analyses were used to examine the intracellular changes of P2X7/FasL signaling. The BV-2 cells and primary microglia from mice genetically deficient in P2X7 were used to further establish a linkage between microglia activation and FasL overproduction.
Results
The FasL expression was continuously elevated and was spatiotemporally related to microglia activation following microsphere embolism. Notably, P2X7 expression concomitantly increased in microglia and presented a distribution pattern that was similar to that of FasL in ED1-positive cells at pathological process of microsphere embolism. Interestingly, FasL generation in cultured microglia cells subjected to oxygen-glucose deprivation-treated neuron-conditioned medium was prevented by the silencing of P2X7. Furthermore, FasL induced the migration of BV-2 microglia, whereas the neutralization of FasL with a blocking antibody was highly effective in inhibiting ischemia-induced microglial mobility. Similar results were observed in primary microglia from wild-type mice or mice genetically deficient in P2X7. Finally, the degrees of FasL overproduction and neuronal death were consistently reduced in P2X7−/− mice compared with wild-type littermates following microsphere embolism insult.
Conclusion
FasL functions as a key component of an immunoreactive response loop by recruiting microglia to the lesion sites through a P2X7-dependent mechanism. The specific modulation of P2X7/FasL signaling and aberrant microglial activation could provide therapeutic benefits in acute and subacute phase of cerebral microembolic injury.
doi:10.1186/1742-2094-9-172
PMCID: PMC3420259  PMID: 22789015
Microsphere embolism; Microglia; P2X7 receptor; Fas ligand; Neuronal cell death
18.  Chemokine CCL2 and its receptor CCR2 in the medullary dorsal horn are involved in trigeminal neuropathic pain 
Background
Neuropathic pain in the trigeminal system is frequently observed in clinic, but the mechanisms involved are largely unknown. In addition, the function of immune cells and related chemicals in the mechanism of pain has been recognized, whereas few studies have addressed the potential role of chemokines in the trigeminal system in chronic pain. The present study was undertaken to test the hypothesis that chemokine C-C motif ligand 2 (CCL2)-chemokine C-C motif receptor 2 (CCR2) signaling in the trigeminal nucleus is involved in the maintenance of trigeminal neuropathic pain.
Methods
The inferior alveolar nerve and mental nerve transection (IAMNT) was used to induce trigeminal neuropathic pain. The expression of ATF3, CCL2, glial fibrillary acidic protein (GFAP), and CCR2 were detected by immunofluorescence histochemical staining and western blot. The cellular localization of CCL2 and CCR2 were examined by immunofluorescence double staining. The effect of a selective CCR2 antagonist, RS504393 on pain hypersensitivity was checked by behavioral testing.
Results
IAMNT induced persistent (>21 days) heat hyperalgesia of the orofacial region and ATF3 expression in the mandibular division of the trigeminal ganglion. Meanwhile, CCL2 expression was increased in the medullary dorsal horn (MDH) from 3 days to 21 days after IAMNT. The induced CCL2 was colocalized with astroglial marker GFAP, but not with neuronal marker NeuN or microglial marker OX-42. Astrocytes activation was also found in the MDH and it started at 3 days, peaked at 10 days and maintained at 21 days after IAMNT. In addition, CCR2 was upregulated by IAMNT in the ipsilateral medulla and lasted for more than 21 days. CCR2 was mainly colocalized with NeuN and few cells were colocalized with GFAP. Finally, intracisternal injection of CCR2 antagonist, RS504393 (1, 10 μg) significantly attenuated IAMNT-induced heat hyperalgesia.
Conclusion
The data suggest that CCL2-CCR2 signaling may be involved in the maintenance of orofacial neuropathic pain via astroglial–neuronal interaction. Targeting CCL2-CCR2 signaling may be a potentially important new treatment strategy for trigeminal neuralgia.
doi:10.1186/1742-2094-9-136
PMCID: PMC3391989  PMID: 22721162
19.  MR Spectroscopy of Normative Premature Newborns 
Purpose
To establish normative metabolite ratios throughout the newborn brain using 3D MR Spectroscopic Imaging.
Materials and Methods
MRI and MRSI have been valuable tools for assessing normal and abnormal neuronal maturation for newborns. In this study, we performed whole brain 3D MRSI in addition to comprehensive anatomic and other functional imaging methods to examine maturation. 55 newborn subjects (28.4 ± 2.6 weeks post-conceptional age at birth, 34.1 ± 3.1 weeks post-conception age at scan, 32 males and 23 females) had high quality MRSI studies (104 exams) and normal neurodevelopmental outcome (NMS=0, MDI>85) at age 12 months.
Results
The NAA to Cho ratio increased significantly with age for all regions. Lac to NAA ratio decreased significantly with age in the regions of thalamus, basal ganglia, cortical spinal tract, and parietal white matter, and showed a decreasing trend in the other regions.
Conclusion
Brain metabolites can be obtained through in vivo 3D MRSI and used to monitor newborn brain maturation.
doi:10.1002/jmri.22460
PMCID: PMC3391540  PMID: 21274971
newborn; brain; spectroscopy; mrsi
20.  Core-clickable PEG-branch-azide bivalent-bottle-brush polymers by ROMP: grafting-through and clicking-to 
The combination of highly efficient polymerizations with modular “click” coupling reactions has enabled the synthesis of wide variety of novel nanoscopic structures. Here we demonstrate the facile synthesis of a new class of clickable, branched nanostructures, polyethylene glycol (PEG)-branch-azide bivalent-brush polymers, facilitated by “graft-through” ring-opening metathesis polymerization (ROMP) of a branched norbornene-PEG-chloride macromonomer followed by halide-azide exchange. The resulting bivalent-brush polymers possess azide groups at the core near a polynorbornene backbone with PEG chains extended into solution; the structure resembles a unimolecular micelle. We demonstrate copper-catalyzed azide-alkyne cycloaddition (CuAAC) “click-to” coupling of a photocleavable doxorubicin (DOX)-alkyne derivative to the azide core. The CuAAC coupling was quantitative across a wide range of nanoscopic sizes (~6 – ~50 nm); UV photolysis of the resulting DOX-loaded materials yielded free DOX that was therapeutically effective against human cancer cells.
doi:10.1021/ja108441d
PMCID: PMC3077470  PMID: 21142161
21.  Expressions of Osteopontin (OPN), ανβ3 and Pim-1 Associated with Poor Prognosis in Non-small Cell Lung Cancer (NSCLC) 
Objective
To examine the expressions of osteopontin (OPN), α ν β3 and Pim-1 in non-small cell lung cancer (NSCLC), and investigate their potential pathogenic roles in the development of NSCLC.
Methods
Immunohistochemistry was used to examine the expressions of OPN, α ν β3 and Pim-1 in cohort (136 cases) of NSCLC samples and their adjacent normal lung tissue specimens. Statistical analysis was performed to evaluate the relationships among expressions of OPN, α ν β3 and Pim-1 and their associations with patients clinico- pathological parameters.
Results
The expressions of OPN and Pim-1 were predominantly observed in cytoplasm. The expression of α ν β3 was mostly detected in cytoplasm and/or membrane. In NSCLC samples, the positive rates of OPN, α ν β3 and Pim-1 expressions were 68.4% (93/136), 77.2% (105/136) and 57.4% (78/136), respectively. In normal lung tissues, in contrast, the positive rates of OPN, α ν β3 and Pim-1 were 24.0% (12/50), 26.0% (13/50) and 16.0% (8/50), respectively. There were significant differences of the positive expression rates of OPN, α ν β3 and Pim-1 between NSCLCs samples and normal lung tissues (P<0.01). In addition, the positive expression of OPN, α ν β3 and Pim-1 in NSCLCs samples was significantly associated with increased pathological grade, lymph node metastasis and advanced clinical stage (P<0.01), and they were independent of other clinicopathological parameters (P>0.05). Furthermore, a significantly positive correlation between the expression of OPN and α ν β3 (r=0.38, P<0.01), OPN and Pim-1 (r=0.37, P<0.01), or α ν β3 and Pim-1 (r=0.20, P<0.05) was evaluated in our NSCLC cohort.
Conclusion
OPN, α ν β3 and Pim-1 proteins are frequently overexpressed in NSCLC, and they may play important roles in the development and/or progression of NSCLC.
doi:10.1007/s11670-012-0103-1
PMCID: PMC3555265  PMID: 23359766
NSCLC; OPN; ανβ3; Pim-1; Immunohistochemistry
22.  Ent-11α-Hydroxy-15-oxo-kaur-16-en-19-oic-acid Inhibits Growth of Human Lung Cancer A549 Cells by Arresting Cell Cycle and Triggering Apoptosis 
Objective
To examine the apoptotic effect of ent-11α-hydroxy-15-oxo-kaur-16-en-19-oic-acid (5F), a compound isolated from Pteris semipinnata L (PsL), in human lung cancer A549 cells.
Methods
A549 cells were treated with 5F (0–80 μg/ml) for different time periods. Cytotoxicity was examined using a MTT method. Cell cycle was examined using propidium iodide staining. Apoptosis was examined using Hoechst 33258 staining, enzyme-linked immunosorbent assay (ELISA) and caspase-3 activity analysis. Expression of representative apoptosis-related proteins was evaluated by Western blot analysis. Reactive oxygen species (ROS) level was measured using standard protocols. Potential interaction of 5F with cisplatin was also examined.
Results
5F inhibited the proliferation of A549 cells in a concentration- and time-dependent manner. 5F increased the accumulation of cells in sub-G1 phase and arrested the cells in the G2 phase. Exposure to 5F induced morphological changes and DNA fragmentation that are characteristic of apoptosis. The expression of p21 was increased. 5F exposure also increased Bax expression, release of cytochrome c and apoptosis inducing factor (AIF), and activation of caspase-3. 5F significantly sensitized the cells to cisplatin toxicity. Interestingly, treatment with 5F did not increase ROS, but reduced ROS production induced by cisplatin.
Conclusion
5F could inhibit the proliferation of A549 cells by arresting the cells in G2 phase and by inducing mitochondrial-mediated apoptosis.
doi:10.1007/s11670-012-0109-8
PMCID: PMC3555272  PMID: 23358391
Pteris semipinnata L; Lung cancer; G2 cell cycle arrest; Apoptosis; Reactive oxygen species
23.  Joint Effects of Febrile Acute Infection and an Interferon-γ Polymorphism on Breast Cancer Risk 
PLoS ONE  2012;7(5):e37275.
Background
There is an inverse relationship between febrile infection and the risk of malignancies. Interferon gamma (IFN-γ) plays an important role in fever induction and its expression increases with incubation at fever-range temperatures. Therefore, the genetic polymorphism of IFN-γ may modify the association of febrile infection with breast cancer risk.
Methodology and Principal Findings
Information on potential breast cancer risk factors, history of fever during the last 10 years, and blood specimens were collected from 839 incident breast cancer cases and 863 age-matched controls between October 2008 and June 2010 in Guangzhou, China. IFN-γ (rs2069705) was genotyped using a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry platform. Odds ratios (OR) and 95% confidence intervals (CIs) were calculated using multivariate logistic regression. We found that women who had experienced ≥1 fever per year had a decreased risk of breast cancer [ORs and 95% CI: 0.77 (0.61–0.99)] compared to those with less than one fever a year. This association only occurred in women with CT/TT genotypes [0.54 (0.37–0.77)] but not in those with the CC genotype [1.09 (0.77–1.55)]. The association of IFN-γ rs2069705 with the risk of breast cancer was not significant among all participants, while the CT/TT genotypes were significantly related to an elevated risk of breast cancer [1.32 (1.03–1.70)] among the women with <1 fever per year and to a reduced risk of breast cancer [0.63 (0.40–0.99)] among women with ≥1 fever per year compared to the CC genotype. A marked interaction between fever frequencies and the IFN-γ genotypes was observed (P for multiplicative and additive interactions were 0.005 and 0.058, respectively).
Conclusions
Our findings indicate a possible link between febrile acute infection and a decreased risk of breast cancer, and this association was modified by IFN-γ rs2069705.
doi:10.1371/journal.pone.0037275
PMCID: PMC3356273  PMID: 22624006
24.  Transport of receptors, receptor signaling complexes and ion channels via neuropeptide-secretory vesicles 
Cell Research  2011;21(5):741-753.
Stimulus-induced exocytosis of large dense-core vesicles (LDCVs) leads to discharge of neuropeptides and fusion of LDCV membranes with the plasma membrane. However, the contribution of LDCVs to the properties of the neuronal membrane remains largely unclear. The present study found that LDCVs were associated with multiple receptors, channels and signaling molecules, suggesting that neuronal sensitivity is modulated by an LDCV-mediated mechanism. Liquid chromatography-mass spectrometry combined with immunoblotting of subcellular fractions identified 298 proteins in LDCV membranes purified from the dorsal spinal cord, including G-protein-coupled receptors, G-proteins and other signaling molecules, ion channels and trafficking-related proteins. Morphological assays showed that δ-opioid receptor 1 (DOR1), β2 adrenergic receptor (AR), Gαi2, voltage-gated calcium channel α2δ1 subunit and P2X purinoceptor 2 were localized in substance P (SP)-positive LDCVs in small-diameter dorsal root ganglion neurons, whereas β1 AR, Wnt receptor frizzled 8 and dishevelled 1 were present in SP-negative LDCVs. Furthermore, DOR1/Gαi2/Gβ1γ5/phospholipase C β2 complexes were associated with LDCVs. Blockade of the DOR1/Gαi2 interaction largely abolished the LDCV localization of Gαi2 and impaired stimulation-induced surface expression of Gαi2. Thus, LDCVs serve as carriers of receptors, ion channels and preassembled receptor signaling complexes, enabling a rapid, activity-dependent modulation of neuronal sensitivity.
doi:10.1038/cr.2011.29
PMCID: PMC3203675  PMID: 21321602
G-protein-coupled receptors; Wnt receptors; Ca2+ channels; large dense-core vesicles; dorsal root ganglion; spinal cord
25.  Expansion of Voltage-dependent Na+ Channel Gene Family in Early Tetrapods Coincided with the Emergence of Terrestriality and Increased Brain Complexity 
Molecular Biology and Evolution  2010;28(4):1415-1424.
Mammals have ten voltage-dependent sodium (Nav) channel genes. Nav channels are expressed in different cell types with different subcellular distributions and are critical for many aspects of neuronal processing. The last common ancestor of teleosts and tetrapods had four Nav channel genes, presumably on four different chromosomes. In the lineage leading to mammals, a series of tandem duplications on two of these chromosomes more than doubled the number of Nav channel genes. It is unknown when these duplications occurred and whether they occurred against a backdrop of duplication of flanking genes on their chromosomes or as an expansion of ion channel genes in general. We estimated key dates of the Nav channel gene family expansion by phylogenetic analysis using teleost, elasmobranch, lungfish, amphibian, avian, lizard, and mammalian Nav channel sequences, as well as chromosomal synteny for tetrapod genes. We tested, and exclude, the null hypothesis that Nav channel genes reside in regions of chromosomes prone to duplication by demonstrating the lack of duplication or duplicate retention of surrounding genes. We also find no comparable expansion in other voltage-dependent ion channel gene families of tetrapods following the teleost–tetrapod divergence. We posit a specific expansion of the Nav channel gene family in the Devonian and Carboniferous periods when tetrapods evolved, diversified, and invaded the terrestrial habitat. During this time, the amniote forebrain evolved greater anatomical complexity and novel tactile sensory receptors appeared. The duplication of Nav channel genes allowed for greater regional specialization in Nav channel expression, variation in subcellular localization, and enhanced processing of somatosensory input.
doi:10.1093/molbev/msq325
PMCID: PMC3058772  PMID: 21148285
sodium channel; tetrapods; amniotes; terrestriality; gene duplication; brain

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