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1.  Antioxidant, Analgesic, Anti-Inflammatory, and Hepatoprotective Effects of the Ethanol Extract of Mahonia oiwakensis Stem 
The aim of this study was to evaluate pharmacological properties of ethanol extracted from Mahonia oiwakensis Hayata stems (MOSEtOH). The pharmacological properties included antioxidant, analgesic, anti-inflammatory and hepatoprotective effects. The protoberberine alkaloid content of the MOSEtOH was analyzed by high-performance liquid chromatography (HPLC). The results revealed that three alkaloids, berberine, palmatine and jatrorrhizine, could be identified. Moreover, the MOSEtOH exhibited antioxidative activity using the DPPH assay (IC50, 0.743 mg/mL). The DPPH radical scavenging activity of MOSEtOH was five times higher that that of vitamin C. MOSEtOH was also found to inhibit pain induced by acetic acid, formalin, and carrageenan inflammation. Treatment with MOSEtOH (100 and 500 mg/kg) or silymarin (200 mg/kg) decreased the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels compared with the CCl4-treated group. Histological evaluation showed that MOSEtOH reduced the degree of liver injury, including vacuolization, inflammation and necrosis of hepatocytes. The anti-inflammatory and hepatoprotective effect of MOSEtOH were found to be related to the modulation of antioxidant enzyme activity in the liver and decreases in malondialdehyde (MDA) level and nitric oxide (NO) contents. Our findings suggest that MOSEtOH has analgesic, anti-inflammatory and hepatoprotective effects. These effects support the use of MOSEtOH for relieving pain and inflammation in folk medicine.
doi:10.3390/ijms14022928
PMCID: PMC3588023  PMID: 23364614
Mahonia oiwakensis Hayata; high-performance liquid chromatography; hepatoprotective effect; malondialdehyde
2.  Accurate Whole Human Genome Sequencing using Reversible Terminator Chemistry 
Bentley, David R. | Balasubramanian, Shankar | Swerdlow, Harold P. | Smith, Geoffrey P. | Milton, John | Brown, Clive G. | Hall, Kevin P. | Evers, Dirk J. | Barnes, Colin L. | Bignell, Helen R. | Boutell, Jonathan M. | Bryant, Jason | Carter, Richard J. | Cheetham, R. Keira | Cox, Anthony J. | Ellis, Darren J. | Flatbush, Michael R. | Gormley, Niall A. | Humphray, Sean J. | Irving, Leslie J. | Karbelashvili, Mirian S. | Kirk, Scott M. | Li, Heng | Liu, Xiaohai | Maisinger, Klaus S. | Murray, Lisa J. | Obradovic, Bojan | Ost, Tobias | Parkinson, Michael L. | Pratt, Mark R. | Rasolonjatovo, Isabelle M. J. | Reed, Mark T. | Rigatti, Roberto | Rodighiero, Chiara | Ross, Mark T. | Sabot, Andrea | Sankar, Subramanian V. | Scally, Aylwyn | Schroth, Gary P. | Smith, Mark E. | Smith, Vincent P. | Spiridou, Anastassia | Torrance, Peta E. | Tzonev, Svilen S. | Vermaas, Eric H. | Walter, Klaudia | Wu, Xiaolin | Zhang, Lu | Alam, Mohammed D. | Anastasi, Carole | Aniebo, Ify C. | Bailey, David M. D. | Bancarz, Iain R. | Banerjee, Saibal | Barbour, Selena G. | Baybayan, Primo A. | Benoit, Vincent A. | Benson, Kevin F. | Bevis, Claire | Black, Phillip J. | Boodhun, Asha | Brennan, Joe S. | Bridgham, John A. | Brown, Rob C. | Brown, Andrew A. | Buermann, Dale H. | Bundu, Abass A. | Burrows, James C. | Carter, Nigel P. | Castillo, Nestor | Catenazzi, Maria Chiara E. | Chang, Simon | Cooley, R. Neil | Crake, Natasha R. | Dada, Olubunmi O. | Diakoumakos, Konstantinos D. | Dominguez-Fernandez, Belen | Earnshaw, David J. | Egbujor, Ugonna C. | Elmore, David W. | Etchin, Sergey S. | Ewan, Mark R. | Fedurco, Milan | Fraser, Louise J. | Fajardo, Karin V. Fuentes | Furey, W. Scott | George, David | Gietzen, Kimberley J. | Goddard, Colin P. | Golda, George S. | Granieri, Philip A. | Green, David E. | Gustafson, David L. | Hansen, Nancy F. | Harnish, Kevin | Haudenschild, Christian D. | Heyer, Narinder I. | Hims, Matthew M. | Ho, Johnny T. | Horgan, Adrian M. | Hoschler, Katya | Hurwitz, Steve | Ivanov, Denis V. | Johnson, Maria Q. | James, Terena | Jones, T. A. Huw | Kang, Gyoung-Dong | Kerelska, Tzvetana H. | Kersey, Alan D. | Khrebtukova, Irina | Kindwall, Alex P. | Kingsbury, Zoya | Kokko-Gonzales, Paula I. | Kumar, Anil | Laurent, Marc A. | Lawley, Cynthia T. | Lee, Sarah E. | Lee, Xavier | Liao, Arnold K. | Loch, Jennifer A. | Lok, Mitch | Luo, Shujun | Mammen, Radhika M. | Martin, John W. | McCauley, Patrick G. | McNitt, Paul | Mehta, Parul | Moon, Keith W. | Mullens, Joe W. | Newington, Taksina | Ning, Zemin | Ng, Bee Ling | Novo, Sonia M. | O'Neill, Michael J. | Osborne, Mark A. | Osnowski, Andrew | Ostadan, Omead | Paraschos, Lambros L. | Pickering, Lea | Pike, Andrew C. | Pike, Alger C. | Pinkard, D. Chris | Pliskin, Daniel P. | Podhasky, Joe | Quijano, Victor J. | Raczy, Come | Rae, Vicki H. | Rawlings, Stephen R. | Rodriguez, Ana Chiva | Roe, Phyllida M. | Rogers, John | Rogert Bacigalupo, Maria C. | Romanov, Nikolai | Romieu, Anthony | Roth, Rithy K. | Rourke, Natalie J. | Ruediger, Silke T. | Rusman, Eli | Sanches-Kuiper, Raquel M. | Schenker, Martin R. | Seoane, Josefina M. | Shaw, Richard J. | Shiver, Mitch K. | Short, Steven W. | Sizto, Ning L. | Sluis, Johannes P. | Smith, Melanie A. | Sohna, Jean Ernest Sohna | Spence, Eric J. | Stevens, Kim | Sutton, Neil | Szajkowski, Lukasz | Tregidgo, Carolyn L. | Turcatti, Gerardo | vandeVondele, Stephanie | Verhovsky, Yuli | Virk, Selene M. | Wakelin, Suzanne | Walcott, Gregory C. | Wang, Jingwen | Worsley, Graham J. | Yan, Juying | Yau, Ling | Zuerlein, Mike | Rogers, Jane | Mullikin, James C. | Hurles, Matthew E. | McCooke, Nick J. | West, John S. | Oaks, Frank L. | Lundberg, Peter L. | Klenerman, David | Durbin, Richard | Smith, Anthony J.
Nature  2008;456(7218):53-59.
doi:10.1038/nature07517
PMCID: PMC2581791  PMID: 18987734
3.  Extremely low-coverage sequencing and imputation increases power for genome-wide association studies 
Nature genetics  2012;44(6):631-635.
Genome wide association studies (GWAS) have proven a powerful method to identify common genetic variants contributing to susceptibility to common diseases. Here we show that extremely low-coverage sequencing (0.1–0.5x) captures almost as much of the common (>5%) and low-frequency (1–5%) variation across the genome as SNP arrays. As an empirical demonstration, we show that genome-wide SNP genotypes can be inferred at a mean r2 of 0.71 using off-target data (0.24x average coverage) in a whole-exome study of 909 samples. Using both simulated and real exome sequencing datasets we show that association statistics obtained using ultra low-coverage sequencing data attain similar P-values at known associated variants as genotyping arrays, without an excess of false positives. Within the context of reductions in sample preparation and sequencing costs, funds invested in ultra low-coverage sequencing can yield several times the effective sample size of SNP-array GWAS, and a commensurate increase in statistical power.
doi:10.1038/ng.2283
PMCID: PMC3400344  PMID: 22610117
4.  Fungal His-Tagged Nitrilase from Gibberella intermedia: Gene Cloning, Heterologous Expression and Biochemical Properties 
PLoS ONE  2012;7(11):e50622.
Background
Nitrilase is an important member of the nitrilase superfamiliy. It has attracted substantial interest from academia and industry for its function of converting nitriles directly into the corresponding carboxylic acids in recent years. Thus nitrilase has played a crucial role in production of commercial carboxylic acids in chemical industry and detoxification of nitrile-contaminated wastes. However, conventional studies mainly focused on the bacterial nitrilase and the potential of fungal nitrilase has been far from being fully explored. Research on fungal nitrilase gene expression will advance our understanding for its biological function of fungal nitrilase in nitrile hydrolysis.
Methodology/Principal Findings
A fungal nitrilase gene from Gibberella intermedia was cloned through reverse transcription-PCR. The open reading frame consisted of 963 bp and potentially encoded a protein of 320 amino acid residues with a theoretical molecular mass of 35.94 kDa. Furthermore, the catalytic triad (Glu-45, Lys-127, and Cys-162) was proposed and confirmed by site-directed mutagenesis. The encoding gene was expressed in Escherichia coli Rosetta-gami (DE3) and the recombinant protein with His6-tag was purified to electrophoretic homogeneity. The purified enzyme exhibited optimal activity at 45°C and pH 7.8. This nitrilase was specific towards aliphatic and aromatic nitriles. The kinetic parameters Vmax and Km for 3-cyanopyridine were determined to be 0.81 µmol/min·mg and 12.11 mM through Hanes-Woolf plot, respectively. 3-Cyanopyridine (100 mM) could be thoroughly hydrolyzed into nicotinic acid within 10 min using the recombinant strain with the release of about 3% nicotinamide and no substrate was detected.
Conclusions/Significance
In the present study, a fungal nitrilase was cloned from the cDNA sequence of G. intermedia and successfully expressed in E. coli Rosetta-gami (DE3). The recombinant strain displayed good 3-cyanopyridine degradation efficiency and wide substrate spectrum. This fungal nitrilase might be a potential candidate for industrial applications in carboxylic acids production.
doi:10.1371/journal.pone.0050622
PMCID: PMC3511519  PMID: 23226336
5.  A statistical framework for SNP calling, mutation discovery, association mapping and population genetical parameter estimation from sequencing data 
Bioinformatics  2011;27(21):2987-2993.
Motivation: Most existing methods for DNA sequence analysis rely on accurate sequences or genotypes. However, in applications of the next-generation sequencing (NGS), accurate genotypes may not be easily obtained (e.g. multi-sample low-coverage sequencing or somatic mutation discovery). These applications press for the development of new methods for analyzing sequence data with uncertainty.
Results: We present a statistical framework for calling SNPs, discovering somatic mutations, inferring population genetical parameters and performing association tests directly based on sequencing data without explicit genotyping or linkage-based imputation. On real data, we demonstrate that our method achieves comparable accuracy to alternative methods for estimating site allele count, for inferring allele frequency spectrum and for association mapping. We also highlight the necessity of using symmetric datasets for finding somatic mutations and confirm that for discovering rare events, mismapping is frequently the leading source of errors.
Availability: http://samtools.sourceforge.net
Contact: hengli@broadinstitute.org
doi:10.1093/bioinformatics/btr509
PMCID: PMC3198575  PMID: 21903627
6.  Nitrilases in nitrile biocatalysis: recent progress and forthcoming research 
Over the past decades, nitrilases have drawn considerable attention because of their application in nitrile degradation as prominent biocatalysts. Nitrilases are derived from bacteria, filamentous fungi, yeasts, and plants. In-depth investigations on their natural sources function mechanisms, enzyme structure, screening pathways, and biocatalytic properties have been conducted. Moreover, the immobilization, purification, gene cloning and modifications of nitrilase have been dwelt upon. Some nitrilases are used commercially as biofactories for carboxylic acids production, waste treatment, and surface modification. This critical review summarizes the current status of nitrilase research, and discusses a number of challenges and significant attempts in its further development. Nitrilase is a significant and promising biocatalyst for catalytic applications.
doi:10.1186/1475-2859-11-142
PMCID: PMC3537687  PMID: 23106943
Biocatalysis; Bioremediation; Carboxylic acid; Gene expression; Immobilization; Nitrilase; Nitrile; Purification; Strain screening; Surface modification
7.  Mobility of Spherical Probe Objects in Polymer Liquids 
Macromolecules  2011;44(19):7853-7863.
We use scaling theory to derive the time dependence of the mean-square displacement 〈Δr2〉 of a spherical probe particle of size d experiencing thermal motion in polymer solutions and melts. Particles with size smaller than solution correlation length ξ undergo ordinary diffusion (〈Δr2 (t)〉 ~ t) with diffusion coefficient similar to that in pure solvent. The motion of particles of intermediate size (ξ < d < a), where a is the tube diameter for entangled polymer liquids, is sub-diffusive (〈Δr2 (t)〉 ~ t1/2) at short time scales since their motion is affected by sub-sections of polymer chains. At long time scales the motion of these particles is diffusive and their diffusion coefficient is determined by the effective viscosity of a polymer liquid with chains of size comparable to the particle diameter d. The motion of particles larger than the tube diameter a at time scales shorter than the relaxation time τe of an entanglement strand is similar to the motion of particles of intermediate size. At longer time scales (t > τe) large particles (d > a) are trapped by entanglement mesh and to move further they have to wait for the surrounding polymer chains to relax at the reptation time scale τrep. At longer times t > τrep, the motion of such large particles (d > a) is diffusive with diffusion coefficient determined by the bulk viscosity of the entangled polymer liquids. Our predictions are in agreement with the results of experiments and computer simulations.
doi:10.1021/ma201583q
PMCID: PMC3205984  PMID: 22058573
8.  The Date of Interbreeding between Neandertals and Modern Humans 
PLoS Genetics  2012;8(10):e1002947.
Comparisons of DNA sequences between Neandertals and present-day humans have shown that Neandertals share more genetic variants with non-Africans than with Africans. This could be due to interbreeding between Neandertals and modern humans when the two groups met subsequent to the emergence of modern humans outside Africa. However, it could also be due to population structure that antedates the origin of Neandertal ancestors in Africa. We measure the extent of linkage disequilibrium (LD) in the genomes of present-day Europeans and find that the last gene flow from Neandertals (or their relatives) into Europeans likely occurred 37,000–86,000 years before the present (BP), and most likely 47,000–65,000 years ago. This supports the recent interbreeding hypothesis and suggests that interbreeding may have occurred when modern humans carrying Upper Paleolithic technologies encountered Neandertals as they expanded out of Africa.
Author Summary
One of the key discoveries from the analysis of the Neandertal genome is that Neandertals share more genetic variants with non-Africans than with Africans. This observation is consistent with two hypotheses: interbreeding between Neandertals and modern humans after modern humans emerged out of Africa or population structure in the ancestors of Neandertals and modern humans. These hypotheses make different predictions about the date of last gene exchange between the ancestors of Neandertals and modern non-Africans. We estimate this date by measuring the extent of linkage disequilibrium (LD) in the genomes of present-day Europeans and find that the last gene flow from Neandertals into Europeans likely occurred 37,000–86,000 years before the present (BP), and most likely 47,000–65,000 years ago. This supports the recent interbreeding hypothesis and suggests that interbreeding occurred when modern humans carrying Upper Paleolithic technologies encountered Neandertals as they expanded out of Africa.
doi:10.1371/journal.pgen.1002947
PMCID: PMC3464203  PMID: 23055938
9.  Excess Body Mass Index and Risk of Liver Cancer: A Nonlinear Dose-Response Meta-Analysis of Prospective Studies 
PLoS ONE  2012;7(9):e44522.
Background
Excess body weight measured as body mass index (BMI) has a positive association with risk of common cancers. However, previous meta-analyses related to BMI and liver cancer had inconsistent results. The purpose of the current study is to establish a nonlinear dose-response relationship between BMI and incidence risk of liver cancer.
Methods
A systematic literature search for relevant articles published from 1966 to November 2011 was conducted in PUBMED and EMBASE digital databases. Additional articles were manually searched by using the reference lists of identified papers. Restricted cubic splines and generalized least-squares regression methods were used to model a potential curvilinear relationship and to make a dose-response meta-analysis. Stratified analysis, sensitivity analysis and assessment of bias were performed in our meta-analysis.
Results
8 articles including 1,779,471 cohort individuals were brought into meta-analysis. A non-linear dose-response association between BMI and risk of liver cancer was visually significant (P for nonlinearity<0.001), besides, the point value of BMI also enhanced the results quantitatively, where relative risks were 1.02 (95%CI = 1.02–1.03), 1.35 (95%CI = 1.24–1.47) and 2.22-fold (95%CI = 1.74–2.83) when BMI was at the point of 25, 30 and 35 kg/m2 compared with reference (the median value of the lowest category), respectively. The ethnicity of the population was found as the main source of heterogeneity. In subsequent stratified analysis, no evidence of heterogeneity was showed in Asian and White populations (P for heterogeneity>0.1), and all value of BMI still presented significantly increased risk of cancer.
Conclusions
The findings from meta-analysis provided that excess BMI had significant increased association with risk of liver cancer, although the biological mechanisms underlying the obesity-cancer link still need to be clarified.
doi:10.1371/journal.pone.0044522
PMCID: PMC3445525  PMID: 23028553
10.  Evaluation of Chinese-Herbal-Medicine-Induced Herb-Drug Interactions: Focusing on Organic Anion Transporter 1 
The consumption of Chinese herbal medicines (CHMs) is increasing exponentially. Many patients utilize CHMs concomitantly with prescription drugs in great frequency. Herb-drug interaction has hence become an important focus of study. Transporter-mediated herb-drug interactions have the potential to seriously influence drug efficacy and toxicity. Since organic anion transporter 1 (OAT1) is crucial in renal active secretion and drug-drug interactions, the possibility of modulation of OAT1-mediated drug transport should be seriously concerned. Sixty-three clinically used CHMs were evaluated in the study. An hOAT1-overexpressing cell line was used for the in vitro CHMs screening, and the effective candidates were administered to Wistar rats to access renal hemodynamics. The regulation of OAT1 mRNA expression was also examined for further evidence of CHMs affecting OAT1-mediated transport. Among all the 63 CHMs, formulae Gui Zhi Fu Ling Wan (GZ) and Chia Wei Hsiao Yao San (CW) exhibited significant inhibitions on hOAT1-mediated [3H]-PAH uptake in vitro and PAH clearance and net secretion in vivo. Moreover, GZ showed concentration-dependent manners both in vitro and in vivo, and the decrease of rOAT1 mRNA expression indicated that GZ not only inhibited function of OAT1 but also suppressed expression of OAT1.
doi:10.1155/2012/967182
PMCID: PMC3440032  PMID: 22988478
11.  Survival Benefit of Tamoxifen in Estrogen Receptor-Negative and Progesterone Receptor-Positive Low Grade Breast Cancer Patients 
Journal of Breast Cancer  2012;15(3):288-295.
Purpose
This study aimed to analyze the efficacy and prognostic significance of adjuvant tamoxifen in breast cancer patients with various hormone receptor statuses.
Methods
Typically, 1,260 female breast cancer patients were recruited in this study. The correlation between estrogen receptor (ER)/progesterone receptor (PR) phenotypes and clinical characteristics was investigated, and the survival rate was assessed after 5-year follow-up.
Results
The 5-year overall survival (85%) was better in women under the age of 50 years. Patients with ER+/PR+ tumors had a better 5-year survival rate (94%); those with ER-/PR- tumors experienced the worst outcome (74% survival rate); whereas single-positive cases were in between. In 97 out of 128 patients with ER-/PR+ tumors, tamoxifen was given as adjuvant hormonal therapy, and it increased the survival benefit in the lower grade group in terms of overall survival and disease-free survival (p=0.01 and p=0.03, respectively).
Conclusion
For high-grade tumors with ER-/PR+, adjuvant tamoxifen therapy may have no survival benefit, whereas for the patients with low-grade ER-/PR+ tumors, adjuvant tamoxifen therapy is highly suggestive.
doi:10.4048/jbc.2012.15.3.288
PMCID: PMC3468782  PMID: 23091541
Breast carcinoma; Estrogen receptor; Progesterone receptor; Tamoxifen
12.  LncRNAs Expression Signatures of Renal Clear Cell Carcinoma Revealed by Microarray 
PLoS ONE  2012;7(8):e42377.
Background
Long noncoding RNAs (lncRNAs) are an important class of pervasive genes involved in a variety of biological functions. They are aberrantly expressed in many types of cancers. In this study, we described lncRNAs profiles in 6 pairs of human renal clear cell carcinoma (RCCC) and the corresponding adjacent nontumorous tissues (NT) by microarray.
Methodology/Principal Findings
With abundant and varied probes accounting 33,045 LncRNAs in our microarray, the number of lncRNAs that expressed at a certain level could be detected is 17157. From the data we found there were thousands of lncRNAs that differentially expressed (≥2 fold-change) in RCCC tissues compared with NT and 916 lncRNAs differentially expressed in five or more of six RCCC samples. Compared with NT, many lncRNAs were significantly up-regulated or down-regulated in RCCC. Our data showed that down-regulated lncRNAs were more common than up-regulated ones. ENST00000456816, X91348, BC029135, NR_024418 were evaluated by qPCR in sixty-three pairs of RCCC and NT samples. The four lncRNAs were aberrantly expressed in RCCC compared with matched histologically normal renal tissues.
Conclusions/Significance
Our study is the first one to determine genome-wide lncRNAs expression patterns in RCCC by microarray. The results displayed that clusters of lncRNAs were aberrantly expressed in RCCC compared with NT samples, which revealed that lncRNAs differentially expressed in tumor tissues and normal tissues may exert a partial or key role in tumor development. Taken together, this study may provide potential targets for future treatment of RCCC and novel insights into cancer biology.
doi:10.1371/journal.pone.0042377
PMCID: PMC3412851  PMID: 22879955
13.  New Variants of Porcine Epidemic Diarrhea Virus, China, 2011 
Emerging Infectious Diseases  2012;18(8):1350-1353.
In 2011, porcine epidemic diarrhea virus (PEDV) infection rates rose substantially in vaccinated swine herds. To determine the distribution profile of PEDV outbreak strains, we sequenced the full-length spike gene from samples from 9 farms where animals exhibited severe diarrhea and mortality rates were high. Three new PEDV variants were identified.
doi:10.3201/eid1808.120002
PMCID: PMC3414035  PMID: 22840964
porcine epidemic diarrhea virus; prevalence; China; phylogeny; variant strain; viruses
14.  Temporal profile of Src, SSeCKS, and angiogenic factors after focal cerebral ischemia: correlations with angiogenesis and cerebral edema 
Neurochemistry international  2011;58(8):872-879.
A better understanding of the underlying mechanisms of angiogenesis and vascular permeability is necessary for the development of therapeutic strategies for ischemic injury. The purpose of this study was to examine the spatial and temporal expression of Src and Src-suppressed C Kinase Substrate (SSeCKS) in brain after middle cerebral artery occlusion (MCAO) and elucidate the relationships among Src, SSeCKS, and the key angiogenic factors present after stroke. Rats were subjected to either MCAO or sham operation. Reverse transcriptase-polymerase chain reaction and Western blotting results revealed that Src gradually increased starting as early as 2 h after MCAO and remained high for 1 day. In contrast, SSeCKS decreased after MCAO. Src expression correlated positively with that of vascular endothelial growth factor and angiopoietin-2, and negatively with that of SSeCKS, angiopoietin-1, and zonula occludens-1. However, SSeCKS had the reverse correlations. Changes in the expression of these factors correlated with the progress of angiogenesis and cerebral edema. Dynamic temporal changes in Src and SSeCKS expression may modulate angiogenesis and cerebral edema formation after focal cerebral ischemia.
doi:10.1016/j.neuint.2011.02.014
PMCID: PMC3100427  PMID: 21334414
Src; SSeCKS; angiogenesis; cerebral edema; ischemia
15.  Structural basis of pre-mRNA recognition by the human cleavage factor Im complex 
Cell Research  2011;21(7):1039-1051.
The cleavage factor Im (CF Im), consists of a 25 kDa subunit (CF Im25) and one of three larger subunits (CF Im59, CF Im68, CF Im72), and is an essential protein complex for pre-mRNA 3′-end cleavage and polyadenylation. It recognizes the upstream sequence of the poly(A) site in a sequence-dependent manner. Here we report the crystal structure of human CF Im, comprising CF Im25 and the RNA recognition motif domain of CF Im68 (CF Im68RRM), and the crystal structure of the CF Im-RNA complex. These structures show that two CF Im68RRM molecules bind to the CF Im25 dimer via a novel RRM-protein interaction mode forming a heterotetramer. The RNA-bound structure shows that two UGUAA RNA sequences, with anti-parallel orientation, bind to one CF Im25-CF Im68RRM heterotetramer, providing structural basis for the mechanism by which CF Im binds two UGUAA elements within one molecule of pre-mRNA simultaneously. Point mutation and kinetic analyses demonstrate that CF Im68RRM can bind the immediately flanking upstream region of the UGUAA element, and CF Im68RRM binding significantly increases the RNA-binding affinity of the complex, suggesting that CF Im68 makes an essential contribution to pre-mRNA binding.
doi:10.1038/cr.2011.67
PMCID: PMC3193493  PMID: 21483454
cleavage factor Im (CF Im); pre-mRNA processing; poly(A) site recognition; RRM domain; RNA binding
16.  Effect of methylprednisolone on the activities of caspase-3, -6, -8 and -9 in rabbits with acute spinal cord injury 
The present study aimed to investigate the effect of methylprednisolone (MP) on the activities of caspase-3, -6, -8 and -9 in rabbits with acute spinal cord injury (ASCI) and to explore the mechanism underlying the antiapoptotic effect of MP on ASCI. Modified Allen’s method was employed to establish the ASCI animal model. The animals were randomly divided into a sham (S; n=12), ASCI (C; n=36) and MP group (T; n=36). At 8, 24 and 72 h and 7, 14 and 28 days after ASCI, the animals were sacrificed and the spinal cord was collected. The absorbance (A) was measured with a microplate reader and the activities of caspase-3, -6, -8 and -9 were calculated followed by comparisons among the groups. In the S group, the activities of the four caspases were low. In the C and T groups, the caspase activities increased at 8 h after injury, peaked at 24 h and remained at a high level 3 days after injury. However, the caspase activities began to decrease at 7 days after injury and were significantly reduced at 14 and 28 days after ASCI. Furthermore, the caspase activities in the T group were markedly lower than those in the C group at 8 and 24 h and 3 and 7 days after surgery (P<0.05), but significant differences were not observed at 14 and 28 days after injury (P>0.05). In conclusion, MP exerted an antiapoptotic effect via inhibition of the activities of caspase-3, -6, -8 and -9 in an animal model of ASCI.
doi:10.3892/etm.2012.552
PMCID: PMC3460301  PMID: 23060921
acute spinal cord injury; methylprednisolone; caspase; apoptotic factors
17.  Improving SNP discovery by base alignment quality 
Bioinformatics  2011;27(8):1157-1158.
Summary: I propose a new application of profile Hidden Markov Models in the area of SNP discovery from resequencing data, to greatly reduce false SNP calls caused by misalignments around insertions and deletions (indels). The central concept is per-Base Alignment Quality, which accurately measures the probability of a read base being wrongly aligned. The effectiveness of BAQ has been positively confirmed on large datasets by the 1000 Genomes Project analysis subgroup.
Availability: http://samtools.sourceforge.net
Contact: hengli@broadinstitute.org
doi:10.1093/bioinformatics/btr076
PMCID: PMC3072548  PMID: 21320865
18.  Tabix: fast retrieval of sequence features from generic TAB-delimited files 
Bioinformatics  2011;27(5):718-719.
Summary: Tabix is the first generic tool that indexes position sorted files in TAB-delimited formats such as GFF, BED, PSL, SAM and SQL export, and quickly retrieves features overlapping specified regions. Tabix features include few seek function calls per query, data compression with gzip compatibility and direct FTP/HTTP access. Tabix is implemented as a free command-line tool as well as a library in C, Java, Perl and Python. It is particularly useful for manually examining local genomic features on the command line and enables genome viewers to support huge data files and remote custom tracks over networks.
Availability and Implementation: http://samtools.sourceforge.net.
Contact: hengli@broadinstitute.org
doi:10.1093/bioinformatics/btq671
PMCID: PMC3042176  PMID: 21208982
19.  Inference of Human Population History From Whole Genome Sequence of A Single Individual 
Nature  2011;475(7357):493-496.
The history of human population size is important to understanding human evolution. Various studies1-5 have found evidence for a founder event (bottleneck) in East Asian and European populations associated with the human dispersal out-of-Africa event around 60 thousand years ago (kya) before present. However, these studies have to assume simplified demographic models with few parameters and do not precisely date the start and stop times of the bottleneck. Here, with fewer assumptions on population size changes, we present a more detailed history of human population sizes between approximately ten thousand to a million years ago, using the pairwise sequentially Markovian coalescent (PSMC) model applied to the complete diploid genome sequences of a Chinese male (YH)6, a Korean male (SJK)7, three European individuals (Venter8, NA12891 and NA128789) and two Yoruba males (NA1850710 and NA19239). We infer that European and Chinese populations had very similar population size histories before 10–20kya. Both populations experienced a severe bottleneck between 10–60kya while African populations experienced a milder bottleneck from which they recovered earlier. All three populations have an elevated effective population size between 60–250kya, possibly due to a population structure11. We also infer that the differentiation of genetically modern humans may have started as early as 100–120kya12, but considerable genetic exchanges may still have occurred until 20–40kya.
doi:10.1038/nature10231
PMCID: PMC3154645  PMID: 21753753
20.  Reversal of type 1 diabetes via islet β cell regeneration following immune modulation by cord blood-derived multipotent stem cells 
BMC Medicine  2012;10:3.
Background
Inability to control autoimmunity is the primary barrier to developing a cure for type 1 diabetes (T1D). Evidence that human cord blood-derived multipotent stem cells (CB-SCs) can control autoimmune responses by altering regulatory T cells (Tregs) and human islet β cell-specific T cell clones offers promise for a new approach to overcome the autoimmunity underlying T1D.
Methods
We developed a procedure for Stem Cell Educator therapy in which a patient's blood is circulated through a closed-loop system that separates lymphocytes from the whole blood and briefly co-cultures them with adherent CB-SCs before returning them to the patient's circulation. In an open-label, phase1/phase 2 study, patients (n = 15) with T1D received one treatment with the Stem Cell Educator. Median age was 29 years (range: 15 to 41), and median diabetic history was 8 years (range: 1 to 21).
Results
Stem Cell Educator therapy was well tolerated in all participants with minimal pain from two venipunctures and no adverse events. Stem Cell Educator therapy can markedly improve C-peptide levels, reduce the median glycated hemoglobin A1C (HbA1C) values, and decrease the median daily dose of insulin in patients with some residual β cell function (n = 6) and patients with no residual pancreatic islet β cell function (n = 6). Treatment also produced an increase in basal and glucose-stimulated C-peptide levels through 40 weeks. However, participants in the Control Group (n = 3) did not exhibit significant change at any follow-up. Individuals who received Stem Cell Educator therapy exhibited increased expression of co-stimulating molecules (specifically, CD28 and ICOS), increases in the number of CD4+CD25+Foxp3+ Tregs, and restoration of Th1/Th2/Th3 cytokine balance.
Conclusions
Stem Cell Educator therapy is safe, and in individuals with moderate or severe T1D, a single treatment produces lasting improvement in metabolic control. Initial results indicate Stem Cell Educator therapy reverses autoimmunity and promotes regeneration of islet β cells. Successful immune modulation by CB-SCs and the resulting clinical improvement in patient status may have important implications for other autoimmune and inflammation-related diseases without the safety and ethical concerns associated with conventional stem cell-based approaches.
Trial registration
ClinicalTrials.gov number, NCT01350219.
doi:10.1186/1741-7015-10-3
PMCID: PMC3322343  PMID: 22233865
21.  Is Remusatia (Araceae) Monophyletic? Evidence from Three Plastid Regions 
The genus Remusatia (Araceae) includes four species distributed in the tropical and subtropical Old World. The phylogeny of Remusatia was constructed using parsimony and Bayesian analyses of sequence data from three plastid regions (the rbcL gene, the trnL-trnF intergenic spacer, and the rps16 intron). Phylogenetic analyses of the concatenated plastid data suggested that the monophyly of Remusatia was not supported because R. hookeriana did not form a clade with the other three species R. vivipara, R. yunnanensis, and R. pumila. Nevertheless, the topology of the analysis constraining Remusatia to monophyly was congruent with the topology of the unconstrained analysis. The results confirmed the inclusion of the previously separate genus Gonatanthus within Remusatia and disagreed with the current infrageneric classification of the genus.
doi:10.3390/ijms13010071
PMCID: PMC3269673  PMID: 22312239
Araceae; phylogeny; Remusatia; taxonomy
22.  2-Phenyl­imidazolium hemi(benzene-1,4-dicarboxyl­ate) trihydrate 
The asymmetric unit of the title compound, C9H9N2 +.0.5C8H4O4 −·3H2O, contains one 2-phenyl­imidazolium cation, half a benzene-1,4-dicarboxyl­ate anion and three water mol­ecules, which are connected by O—H⋯O and N—H⋯O hydrogen bonds into a three-dimensional network.
doi:10.1107/S1600536811044953
PMCID: PMC3238829  PMID: 22199682
23.  Time course of upregulation of inflammatory mediators in the hemorrhagic brain in rats: correlation with brain edema 
Neurochemistry international  2010;57(3):248-253.
Intracerebral hemorrhage (ICH) can cause secondary brain damage through inflammation-related pathways. Thrombin and one of its receptors, protease activated receptor-1 (PAR-1); matrix metalloproteinase (MMP)-9; and aquaporin (AQP)-4 are stroke-related inflammatory mediators that have been implicated in ICH pathology. To further characterize the inflammatory response after ICH, we studied the temporal profile of the expression of these inflammatory mediators and assessed their potential correlation with brain edema formation after brain hemorrhage in rats. ICH was modeled by infusing autologous blood into the striatum. Then mRNA and protein expression was assessed over the course of 5 days. We found that the mRNA and/or protein expression of thrombin, PAR-1, AQP-4, and MMP-9 was upregulated between 2 h and 5 days after ICH. Each reached a maximal level at day 2, except for AQP-4 protein, which peaked at day 5. Brain water content after ICH presented a similar trend; it was increased at 2 h, peaked at day 2, and then decreased but remained elevated at day 5. Our data provide novel evidence that upregulation of these selected inflammatory mediators occurs very early and persists for several days after ICH, and that temporal patterns of expression of thrombin and AQP-4 are associated with brain edema formation. These findings have important implications for efforts to reduce secondary brain damage after ICH.
doi:10.1016/j.neuint.2010.06.002
PMCID: PMC2910823  PMID: 20541575
Aquaporin-4; Blood; MMP-9; PAR-1; Thrombin; Intracerebral hemorrhage
24.  A survey of sequence alignment algorithms for next-generation sequencing 
Briefings in Bioinformatics  2010;11(5):473-483.
Rapidly evolving sequencing technologies produce data on an unparalleled scale. A central challenge to the analysis of this data is sequence alignment, whereby sequence reads must be compared to a reference. A wide variety of alignment algorithms and software have been subsequently developed over the past two years. In this article, we will systematically review the current development of these algorithms and introduce their practical applications on different types of experimental data. We come to the conclusion that short-read alignment is no longer the bottleneck of data analyses. We also consider future development of alignment algorithms with respect to emerging long sequence reads and the prospect of cloud computing.
doi:10.1093/bib/bbq015
PMCID: PMC2943993  PMID: 20460430
new sequencing technologies; alignment algorithm; sequence analysis
25.  Starting dynamics of dissipative-soliton fiber laser 
Optics letters  2010;35(14):2403-2405.
We study the starting dynamics of an all-normal-dispersion Yb-doped fiber laser experimentally and compare them to an existing stochastic model of starting from quantum noise. The laser reaches mode locking 10 to 100 times faster than a soliton laser with similar parameters. According to the model, the fast starting can be attributed to the large pulse energy in the normal-dispersion laser. We also report direct observations of starting from relaxation oscillations and discuss that process in light of the theory.
PMCID: PMC3144323  PMID: 20634844

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