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1.  The relationship between regional abdominal fat distribution and both insulin resistance and subclinical chronic inflammation in non-diabetic adults 
Obesity is associated with a high risk of insulin resistance (IR) and its metabolic complications. It is still debated that distributions of adipose tissue relate to an excess risk of IR and chronic inflammation in different race. This study was designed to examine the relation between insulin sensitivity, chronic inflammation and central fat distribution in non-diabetic volunteers in Taiwanese.
There were 328 volunteers without family history of diabetes mellitus and with normal oral glucose tolerance test enrolled. Total body fat and abdominal fat were measured. Abdominal fat was categorized into intraperitoneal (IP), retroperitoneal (RP) and subcutaneous (SC) fat. The IR index was estimated by homeostatic model assessment. Five inflammatory markers: adiponectin, leptin, tumor necrosing factor-α (TNF-α), resistin and high sensitive CRP (hs-CRP) were measured.
IR was related to IP fat (r = 0.23, p < 0.001), but not RP fat, SC fat or total body fat. After correcting for age and sex, IP fat was the only significant predictor of IR (r2 = 58%, p = 0.001). Leptin showed the strongest relationship with all fat compartments (IP fat: r = 0.44, p = 0.001; RP fat: r = 0.36, p = 0.005, SC fat: r = 0.54, p < 0.001; total body fat: r = 0.61, p < 0.001). The hs-CRP and adiponectin were closely related both to IP (r = 0.29, p = 0.004; r = -0.20, p = 0.046, respectively) and total body fat (r = 0.29, p = 0.004; r = -0.29, p = 0.005, respectively), but not RP, or SC fat. TNF-α and resistin were not correlated to any fat compartment. After correcting for age and sex, leptin variance was mostly explained by SC fat (41.3%), followed by IP fat (33.6%) and RP fat (25.3%). The hs-CRP and adiponectin variance were mostly explained by IP fat (40% and 49% respectively).
IP fat is better predictors of IR and subclinical chronic inflammation in Taiwanese adults. A disproportionate accumulation of abdominal fat is associated with increased risk of cardiovascular diseases.
PMCID: PMC3978053  PMID: 24684833
Subcutaneous fat; Intra-peritoneal fat; Retroperitoneal fat; Insulin resistance; High sensitive C-reactive protein; Adiponectin
2.  Spatial variations of community structures and methane cycling across a transect of Lei-Gong-Hou mud volcanoes in eastern Taiwan 
This study analyzed cored sediments retrieved from sites distributed across a transect of the Lei-Gong-Hou mud volcanoes in eastern Taiwan to uncover the spatial distributions of biogeochemical processes and community assemblages involved in methane cycling. The profiles of methane concentration and carbon isotopic composition revealed various orders of the predominance of specific methane-related metabolisms along depth. At a site proximal to the bubbling pool, the methanogenic zone was sandwiched by the anaerobic methanotrophic zones. For two sites distributed toward the topographic depression, the methanogenic zone overlaid the anaerobic methanotrophic zone. The predominance of anaerobic methanotrophy at specific depth intervals is supported by the enhanced copy numbers of the ANME-2a 16S rRNA gene and coincides with high dissolved Fe/Mn concentrations and copy numbers of the Desulfuromonas/Pelobacter 16S rRNA gene. Assemblages of 16S rRNA and mcrA genes revealed that methanogenesis was mediated by Methanococcoides and Methanosarcina. pmoA genes and a few 16S rRNA genes related to aerobic methanotrophs were detected in limited numbers of subsurface samples. While dissolved Fe/Mn signifies the presence of anaerobic metabolisms near the surface, the correlations between geochemical characteristics and gene abundances, and the absence of aerobic methanotrophs in top sediments suggest that anaerobic methanotrophy is potentially dependent on iron/manganese reduction and dominates over aerobic methanotrophy for the removal of methane produced in situ or from a deep source. Near-surface methanogenesis contributes to the methane emissions from mud platform. The alternating arrangements of methanogenic and methanotrophic zones at different sites suggest that the interactions between mud deposition, evaporation, oxidation and fluid transport modulate the assemblages of microbial communities and methane cycling in different compartments of terrestrial mud volcanoes.
PMCID: PMC3971192  PMID: 24723919
mud volcano; methanogenesis; methanotrophy; metal reduction; ANME group; Taiwan
3.  Unusual Compression Behavior of Nanocrystalline CeO2 
Scientific Reports  2014;4:4441.
The x-ray diffraction study of 12 nm CeO2 was carried out up to ~40 GPa using an angle dispersive synchrotron-radiation in a diamond-anvil cell with different pressure transmitting medium (PTM) (4:1 methanol: ethanol mixture, silicone oil and none) at room temperature. While the cubic fluorite-type structure CeO2 was retained to the highest pressure, there is progressive broadening and intensity reduction of the reflections with increasing pressure. At pressures above 12 GPa, an unusual change in the compression curve was detected in all experiments. Significantly, apparent negative volume compressibility was observed at P = 18–27 GPa with silicone oil as PTM, however it was not detected in other circumstances. The expansion of the unit cell volume of cubic CeO2 was about 1% at pressures of 15–27 GPa. To explain this abnormal phenomenon, a dual structure model (hard amorphous shell and relatively soft crystalline core) has been proposed.
PMCID: PMC3963033  PMID: 24658049
4.  A 13-gene signature prognostic of HPV-negative OSCC: discovery and external validation 
To identify a prognostic gene signature for HPV-negative OSCC patients.
Experimental Design
Two gene expression datasets were used; a training dataset from the Fred Hutchinson Cancer Research Center (FHCRC) (n=97), and a validation dataset from the MD Anderson Cancer Center (MDACC) (n=71). We applied L1/L2-penalized Cox regression models to the FHCRC data on the 131–gene signature previously identified to be prognostic in OSCC patients to identify a prognostic model specific for high-risk HPV-negative OSCC patients. The models were tested with the MDACC dataset using a receiver operating characteristic analysis.
A 13-gene model was identified as the best predictor of HPV-negative OSCC-specific survival in the training dataset. The risk score for each patient in the validation dataset was calculated from this model and dichotomized at the median. The estimated 2-year mortality (± SE) of patients with high risk scores was 47.1 (±9.24)% compared with 6.35 (± 4.42)% for patients with low risk scores. ROC analyses showed that the areas under the curve for the age, gender, and treatment modality-adjusted models with risk score (0.78, 95%CI: 0.74-0.86) and risk score plus tumor stage (0.79, 95%CI: 0.75-0.87) were substantially higher than for the model with tumor stage (0.54, 95%CI: 0.48-0.62).
We identified and validated a 13-gene signature that is considerably better than tumor stage in predicting survival of HPV-negative OSCC patients. Further evaluation of this gene signature as a prognostic marker in other populations of patients with HPV-negative OSCC is warranted.
PMCID: PMC3593802  PMID: 23319825
gene signature; prognosis; HPV-negative; OSCC
5.  Activation of VCAM-1 and Its Associated Molecule CD44 Leads to Increased Malignant Potential of Breast Cancer Cells 
VCAM-1 (CD106), a transmembrane glycoprotein, was first reported to play an important role in leukocyte adhesion, leukocyte transendothelial migration and cell activation by binding to integrin VLA-1 (α4β1). In the present study, we observed that VCAM-1 expression can be induced in many breast cancer epithelial cells by cytokine stimulation in vitro and its up-regulation directly correlated with advanced clinical breast cancer stage. We found that VCAM-1 over-expression in the NMuMG breast epithelial cells controls the epithelial and mesenchymal transition (EMT) program to increase cell motility rates and promote chemoresistance to doxorubicin and cisplatin in vitro. Conversely, in the established MDAMB231 metastatic breast cancer cell line, we confirmed that knockdown of endogenous VCAM-1 expression reduced cell proliferation and inhibited TGFβ1 or IL-6 mediated cell migration, and increased chemosensitivity. Furthermore, we demonstrated that knockdown of endogenous VCAM-1 expression in MDAMB231 cells reduced tumor formation in a SCID xenograft mouse model. Signaling studies showed that VCAM-1 physically associates with CD44 and enhances CD44 and ABCG2 expression. Our findings uncover the possible mechanism of VCAM-1 activation facilitating breast cancer progression, and suggest that targeting VCAM-1 is an attractive strategy for therapeutic intervention.
PMCID: PMC3975354  PMID: 24583847
VCAM-1; breast cancer progression; EMT; metastasis; chemoresistance
The annals of applied statistics  2013;7(1):391-417.
Gaussian Graphical Models (GGMs) have been used to construct genetic regulatory networks where regularization techniques are widely used since the network inference usually falls into a high–dimension–low–sample–size scenario. Yet, finding the right amount of regularization can be challenging, especially in an unsupervised setting where traditional methods such as BIC or cross-validation often do not work well. In this paper, we propose a new method — Bootstrap Inference for Network COnstruction (BINCO) — to infer networks by directly controlling the false discovery rates (FDRs) of the selected edges. This method fits a mixture model for the distribution of edge selection frequencies to estimate the FDRs, where the selection frequencies are calculated via model aggregation. This method is applicable to a wide range of applications beyond network construction. When we applied our proposed method to building a gene regulatory network with microarray expression breast cancer data, we were able to identify high-confidence edges and well-connected hub genes that could potentially play important roles in understanding the underlying biological processes of breast cancer.
PMCID: PMC3930359  PMID: 24563684
high dimensional data; GGM; model aggregation; mixture model; FDR
Journal of statistical research  2010;44(1):103-107.
In a recent paper [4], Efron pointed out that an important issue in large-scale multiple hypothesis testing is that the null distribution may be unknown and need to be estimated. Consider a Gaussian mixture model, where the null distribution is known to be normal but both null parameters-the mean and the variance-are unknown. We address the problem with a method based on Fourier transformation. The Fourier approach was first studied by Jin and Cai [9], which focuses on the scenario where any non-null effect has either the same or a larger variance than that of the null effects. In this paper, we review the main ideas in [9], and propose a generalized Fourier approach to tackle the problem under another scenario: any non-null effect has a larger mean than that of the null effects, but no constraint is imposed on the variance. This approach and that in [9] complement with each other: each approach is successful in a wide class of situations where the other fails. Also, we extend the Fourier approach to estimate the proportion of non-null effects. The proposed procedures perform well both in theory and on simulated data.
PMCID: PMC3928715  PMID: 24563569
empirical null; Fourier transformation; generalized Fourier transformation; proportion of non-null effects; sample size calculation
8.  Genetic Polymorphism of Apolipoprotein A5 Gene and Susceptibility to Type 2 Diabetes Mellitus: A Meta-Analysis of 15,137 Subjects 
PLoS ONE  2014;9(2):e89167.
Several studies have investigated whether the polymorphism in the apolipoprotein A5 (APOA5) is associated with type 2 diabetes mellitus (T2DM) risk. However, those studies have produced inconsistent results. The purpose of this study was to investigate whether the APOA5 -1131T/C polymorphism (rs662799) confers significant susceptibility to T2DM using a meta-analysis.
PubMed, Embase, Web of Science, Cochrane database, CBMdisc, CNKI and Google Scholar were searched to get the genetic association studies. All statistical analyses were done with Stata 11.0.
A total of 19 studies included 4,767 T2DM cases and 10,370 controls (four studies involving 555 T2DM cases and 2958 controls were performed among Europeans and 15 studies involving 4212 T2DM cases and 7412 controls were performed among Asians) were combined showing significant association between the APOA5 -1131T/C polymorphism and T2DM risk (for C allele vs. T allele: OR = 1.28, 95% CI = 1.17–1.40, p<0.00001; for C/C vs. T/T: OR = 1.57, 95% CI = 1.35–1.83, p<0.00001; for C/C vs. T/C+T/T: OR = 1.36, 95% CI = 1.18–1.57, p<0.0001; for C/C+T/C vs. T/T: OR = 1.32, 95% CI = 1.16–1.51, p<0.0001). In the subgroup analysis by ethnicity, significant association was also found among Asians (for C allele vs. T allele: OR = 1.31, 95% CI = 1.22–1.40, p<0.00001; for C/C vs. T/T: OR = 1.61, 95% CI = 1.38–1.88, p<0.00001; for C/C vs. T/C+T/T: OR = 1.39, 95% CI = 1.20–1.61, p<0.0001; for C/C+T/C vs. T/T: OR = 1.42, 95% CI = 1.25–1.62, p<0.00001). However, no significant association was found between the APOA5 -1131T/C polymorphism and T2DM risk among Europeans.
The present meta-analysis suggests that the APOA5 -1131T/C polymorphism is associated with an increased T2DM risk in Asian population.
PMCID: PMC3929635  PMID: 24586566
9.  Nephroprotective effect of astaxanthin against trivalent inorganic arsenic-induced renal injury in wistar rats 
Inorganic arsenic (iAs) is a toxic metalloid found ubiquitously in the environment. In humans, exposure to iAs can result in toxicity and cause toxicological manifestations. Arsenic trioxide (As2O3) has been used in the treatment for acute promyelocytic leukemia. The kidney is the critical target organ of trivalent inorganic As (iAsIII) toxicity. We examine if oral administration of astaxanthin (AST) has protective effects on nephrotoxicity and oxidative stress induced by As2O3 exposure (via intraperitoneal injection) in rats. Markers of renal function, histopathological changes, Na+-K+ ATPase, sulfydryl, oxidative stress, and As accumulation in kidneys were evaluated as indicators of As2O3 exposure. AST showed a significant protective effect against As2O3-induced nephrotoxicity. These results suggest that the mechanisms of action, by which AST reduces nephrotoxicity, may include antioxidant protection against oxidative injury and reduction of As accumulation. These findings might be of therapeutic benefit in humans or animals suffering from exposure to iAsIII from natural sources or cancer therapy.
PMCID: PMC3944156  PMID: 24611105
Astaxanthin; trivalent inorganic arsenic; arsenic accumulation; nephrotoxicity; oxidative stress
10.  Regularized Multivariate Regression for Identifying Master Predictors with Application to Integrative Genomics Study of Breast Cancer 
In this paper, we propose a new method remMap — REgularized Multivariate regression for identifying MAster Predictors — for fitting multivariate response regression models under the high-dimension-low-sample-size setting. remMap is motivated by investigating the regulatory relationships among different biological molecules based on multiple types of high dimensional genomic data. Particularly, we are interested in studying the influence of DNA copy number alterations on RNA transcript levels. For this purpose, we model the dependence of the RNA expression levels on DNA copy numbers through multivariate linear regressions and utilize proper regularization to deal with the high dimensionality as well as to incorporate desired network structures. Criteria for selecting the tuning parameters are also discussed. The performance of the proposed method is illustrated through extensive simulation studies. Finally, remMap is applied to a breast cancer study, in which genome wide RNA transcript levels and DNA copy numbers were measured for 172 tumor samples. We identify a trans-hub region in cytoband 17q12–q21, whose amplification influences the RNA expression levels of more than 30 unlinked genes. These findings may lead to a better understanding of breast cancer pathology.
PMCID: PMC3905690  PMID: 24489618
sparse regression; MAP(MAster Predictor) penalty; DNA copy number alteration; RNA transcript level; v-fold cross validation
11.  Revision of three camaenid and one bradybaenid species (Gastropoda, Stylommatophora) from China based on morphological and molecular data, with description of a new bradybaenid subspecies from Inner Mongolia, China 
ZooKeys  2014;1-16.
We have revised the taxonomy of three camaenid and one bradybaenid species from China and described one new subspecies of the genus Bradybaena (Family Bradybaenidae) from Inner Mongolia, China. The genitalia of three Satsuma (Family Camaenidae) species S. mellea stenozona (Moellendorff, 1884), S. meridionalis (Moellendorff, 1884), comb. n. and S. uncopila (Heude, 1882), comb. n. assigned to the genus Bradybaena previously,lack a dart sac and mucous glands. Moreover, the molecular phylogeny has revealed close relationships between the three species and the genus Satsuma. Two species, S. stenozona (Moellendorff, 1884) from Fuzhou and Ganesella citrina Zilch, 1940 from Wuyi Mountain, are considered as synonymous and should be a subspecies of S. mellea mellea (Pfeiffer, 1866) because of the morphological and molecular similarities. Meanwhile, the other two are placed in the genus Satsuma: S. meridionalis (Moellendorff, 1884), comb. n. and S. uncopila (Heude, 1882), comb. n. G. virgo Pilsbry, 1927 differs from species of the genera Ganesella and Satsuma not only in its shell, but also in anatomical characters, such as having a dart sac and mucous gland, and lacking a flagellum. Additionally, phylogenetic analyses highly support the sister relationship with other Bradybaena species. Thus, placement of G. virgo Pilsbry, 1927 in the genus Bradybaena issuggested.
PMCID: PMC3909801  PMID: 24493955
Satsuma; Ganesella; Bradybaena; revision; new subspecies
12.  Patterns of striatal degeneration in frontotemporal dementia 
Behavioral variant frontotemporal dementia and semantic dementia have been associated with striatal degeneration, but few studies have delineated striatal subregion volumes in vivo or related them to clinical phenotype. We traced caudate, putamen, and nucleus accumbens on MR images to quantify volumes of these structures in behavioral variant frontotemporal dementia, semantic dementia, Alzheimer’s disease, and healthy controls (n = 12 per group). We further related these striatal volumes to clinical deficits and neuropathological findings in a subset of patients. Behavioral variant frontotemporal dementia and semantic dementia showed significant overall striatal atrophy compared with controls. Moreover, behavioral variant frontotemporal dementia showed panstriatal degeneration whereas semantic dementia featured a more focal pattern involving putamen and accumbens. Right-sided striatal atrophy, especially in the putamen, correlated with overall behavioral symptom severity and with specific behavioral domains. At autopsy, patients with behavioral variant frontotemporal dementia and semantic dementia showed striking and severe tau or TAR DNA-binding protein of 43 kDa pathology, especially in ventral parts of the striatum. These results demonstrate that ventral striatum degeneration is a prominent shared feature in behavioral variant frontotemporal dementia and semantic dementia and may contribute to social-emotional deficits common to both disorders.
PMCID: PMC3389579  PMID: 22367382
13.  Resveratrol Partially Prevents Rotenone-Induced Neurotoxicity in Dopaminergic SH-SY5Y Cells through Induction of Heme Oxygenase-1 Dependent Autophagy 
Parkinson disease (PD) is a complex neurodegenerative disorder characterized by a progressive loss of dopaminergic neurons. Mitochondrial dysfunction, oxidative stress or protein misfolding and aggregation may underlie this process. Autophagy is an intracellular catabolic mechanism responsible for protein degradation and recycling of damaged proteins and cytoplasmic organelles. Autophagic dysfunction may hasten the progression of neuronal degeneration. In this study, resveratrol promoted autophagic flux and protected dopaminergic neurons against rotenone-induced apoptosis. In an in vivo PD model, rotenone induced loss of dopaminergic neurons, increased oxidation of mitochondrial proteins and promoted autophagic vesicle development in brain tissue. The natural phytoalexin resveratrol prevented rotenone-induced neuronal apoptosis in vitro, and this pro-survival effect was abolished by an autophagic inhibitor. Although both rotenone and resveratrol promoted LC3-II accumulation, autophagic flux was inhibited by rotenone and augmented by resveratrol. Further, rotenone reduced heme oxygenase-1 (HO-1) expression, whereas resveratrol increased HO-1 expression. Pharmacological inhibition of HO-1 abolished resveratrol-mediated autophagy and neuroprotection. Notably, the effects of a pharmacological inducer of HO-1 were similar to those of resveratrol, and protected against rotenone-induced cell death in an autophagy-dependent manner, validating the hypothesis of HO-1 dependent autophagy in preventing neuronal death in the in vitro PD model. Collectively, our findings suggest that resveratrol induces HO-1 expression and prevents dopaminergic cell death by regulating autophagic flux; thus protecting against rotenone-induced neuronal apoptosis.
PMCID: PMC3907890  PMID: 24451142
Parkinson’s disease; oxidative stress; mitochondrial dysfunction; autophagy; apoptosis; resveratrol; heme oxygenase-1
14.  Alkaloids from the Mangrove-Derived Actinomycete Jishengella endophytica 161111 
Marine Drugs  2014;12(1):477-490.
A new alkaloid, 2-(furan-2-yl)-6-(2S,3S,4-trihydroxybutyl)pyrazine (1), along with 12 known compounds, 2-(furan-2-yl)-5-(2S,3S,4-trihydroxybutyl)pyrazine (2), (S)-4-isobutyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (3), (S)-4-isopropyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (4), (4S)-4-(2-methylbutyl)-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (5), (S)-4-benzyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (6), flazin (7), perlolyrine (8), 1-hydroxy-β-carboline (9), lumichrome (10), 1H-indole-3-carboxaldehyde (11), 2-hydroxy-1-(1H-indol-3-yl)ethanone (12), and 5-(methoxymethyl)-1H-pyrrole-2-carbaldehyde (13), were isolated and identified from the fermentation broth of an endophytic actinomycetes, Jishengella endophytica 161111. The new structure 1 and the absolute configurations of 2–6 were determined by spectroscopic methods, J-based configuration analysis (JBCA) method, lactone sector rule, and electronic circular dichroism (ECD) calculations. Compounds 8–11 were active against the influenza A virus subtype H1N1 with IC50 and selectivity index (SI) values of 38.3(±1.2)/25.0(±3.6)/39.7(±5.6)/45.9(±2.1) μg/mL and 3.0/16.1/3.1/11.4, respectively. The IC50 and SI values of positive control, ribavirin, were 23.1(±1.7) μg/mL and 32.2, respectively. The results showed that compound 9 could be a promising new hit for anti-H1N1 drugs. The absolute configurations of 2–5, 13C nuclear magnetic resonance (NMR) data and the specific rotations of 3–6 were also reported here for the first time.
PMCID: PMC3917282  PMID: 24451190
mangrove; actinomycete; Jishengella endophytica 161111; pyrazine derivative; anti-H1N1 virus activity
15.  Characterization of Four Novel Caspases from Litopenaeus vannamei (Lvcaspase2-5) and Their Role in WSSV Infection through dsRNA-Mediated Gene Silencing 
PLoS ONE  2013;8(12):e80418.
Apoptosis plays an important role in white spot syndrome virus (WSSV) pathogenesis, and caspases are central players in apoptosis. Here, we cloned four novel caspases (Lvcaspase2-5) from the Pacific white shrimp Litopenaeus vannamei, and investigated their potential roles in WSSV replication using dsRNA-mediated gene silencing. Lvcaspase2-5 have the typical domain structure of caspase family proteins, with the conserved consensus motifs p20 and p10. Lvcaspase2 and Lvcaspase5 were highly expressed in muscle, while Lvcaspase3 was highly expressed in hemocytes and Lvcaspase4 was mainly expressed in intestine. Lvcaspase2-5 could also be upregulated by WSSV infection, and they showed different patterns in various tissues. When overexpressed in Drosophila S2 cells, Lvcaspase2-5 showed different cellular localizations. Using dsRNA-medicated gene silencing, the expression of Lvcaspase2, Lvcaspase3, and Lvcaspase5 were effectively knocked down. In Lvcaspase2-, Lvcaspase3- or Lvcaspase5-silenced L. vannamei, expression of WSSV VP28 gene was significantly enhanced, suggesting protective roles for Lvcaspase2, Lvcaspase3 and Lvcaspase5 in the host defense against WSSV infection.
PMCID: PMC3871164  PMID: 24376496
16.  Network Based Prediction Model for Genomics Data Analysis* 
Statistics in biosciences  2012;4(1):10.1007/s12561-012-9056-7.
Biological networks, such as genetic regulatory networks and protein interaction networks, provide important information for studying gene/protein activities. In this paper, we propose a new method, NetBoosting, for incorporating a priori biological network information in analyzing high dimensional genomics data. Specially, we are interested in constructing prediction models for disease phenotypes of interest based on genomics data, and at the same time identifying disease susceptible genes. We employ the gradient descent boosting procedure to build an additive tree model and propose a new algorithm to utilize the network structure in fitting small tree weak learners. We illustrate by simulation studies and a real data example that, by making use of the network information, NetBoosting outperforms a few existing methods in terms of accuracy of prediction and variable selection.
PMCID: PMC3859188  PMID: 24348880
17.  Metabolic stratification driven by surface and subsurface interactions in a terrestrial mud volcano 
The ISME Journal  2012;6(12):2280-2290.
Terrestrial mud volcanism represents the prominent surface geological feature, where fluids and hydrocarbons are discharged along deeply rooted structures in tectonically active regimes. Terrestrial mud volcanoes (MVs) directly emit the major gas phase, methane, into the atmosphere, making them important sources of greenhouse gases over geological time. Quantification of methane emission would require detailed insights into the capacity and efficiency of microbial metabolisms either consuming or producing methane in the subsurface, and establishment of the linkage between these methane-related metabolisms and other microbial or abiotic processes. Here we conducted geochemical, microbiological and genetic analyses of sediments, gases, and pore and surface fluids to characterize fluid processes, community assemblages, functions and activities in a methane-emitting MV of southwestern Taiwan. Multiple lines of evidence suggest that aerobic/anaerobic methane oxidation, sulfate reduction and methanogenesis are active and compartmentalized into discrete, stratified niches, resembling those in marine settings. Surface evaporation and oxidation of sulfide minerals are required to account for the enhanced levels of sulfate that fuels subsurface sulfate reduction and anaerobic methanotrophy. Methane flux generated by in situ methanogenesis appears to alter the isotopic compositions and abundances of thermogenic methane migrating from deep sources, and to exceed the capacity of microbial consumption. This metabolic stratification is sustained by chemical disequilibria induced by the mixing between upward, anoxic, methane-rich fluids and downward, oxic, sulfate-rich fluids.
PMCID: PMC3504961  PMID: 22739492
metabolic stratification; terrestrial mud volcano; sulfate-to-methane transition zone; methanogenesis; 16S rRNA gene clone library; metagenome
18.  Potential biomarkers for paclitaxel sensitivity in hypopharynx cancer cell 
Paclitaxel has been proved to be active in treatment and larynx preservation of HNSCC, however, the fact that about 20-40% patients do not respond to paclitaxel makes it urgent to figure out the biomarkers for paclitaxel-based treatment in Hypopharynx cancer (HPC) patients to improve the therapy effect. In this work, Fadu cells, treated or untreated with low dose of paclitaxel for 24 h, were applied to DNA microarray chips. The differential expression in mRNAs and miRs was analyzed and the network between expression-altered mRNAs and miRs was constructed. Differentially expressed genes were mainly enriched in superpathway of cholesterol biosynthesis (ACAT2, MSMO1, LSS, FDFT1 and FDPS etc.), complement system (C3, C1R, C1S, CFR and CFB etc.), interferon signaling (IFIT1, IFIT3, IFITM1 and MX1 etc.), mTOR signaling (MRAS, PRKAA2, PLD1, RND3 and EIF4A1 etc.) and IGF1 signaling (MRAS, IGFBP7, JUN and FOS etc.), most of these pathways are implicated in tumorigenesis or chemotherapy resistance. The first three pathways were predicted to be suppressed, while the last two pathways were predicted to be induced by paclitaxel, suggesting the combination therapy with mTOR inhibition and paclitaxel might be better than single one. The dramatically expression-altered miRs were miR-112, miR-7, miR-1304, miR-222*, miR-29b-1* (these five miRs were upregulated) and miR-210 (downregulated). The 26 putative target genes mediated by the 6 miRs were figured out and the miR-gene network was constructed. Furthermore, immunoblotting assay showed that ERK signaling in Fadu cells was active by low dose of paclitaxel but repressed by high dose of paclitaxel. Collectively, our data would provide potential biomarkers and therapeutic targets for paclitaxel-based therapy in HPC patients.
PMCID: PMC3843255  PMID: 24294361
Paclitaxel; hypopharynx cancer; DNA microarray; mTOR signaling
19.  Urinary Function following Laparoscopic Lymphadenectomy for Male Rectal Cancer 
PLoS ONE  2013;8(11):e78701.
Urinary function can be protected following open lateral node dissection (LND) with pelvic autonomic nerve preservation (PANP) for advanced rectal cancer. However data regarding urinary function after laparoscopic LND with PANP have not been reported. The goal of this study was to determine the effects of laparoscopic LND with PANP on urinary function in male patients with rectal cancer.
Urine flowmetry was performed using an Urodyn flowmeter. Patients were also asked to complete the standardized International Prostate Symptom Score (IPSS) questionnaire before surgery and 6 months after. In total, this study consisted of 60 males with advanced rectal cancer.
No significant differences were seen in maximal urinary flow rate, voided volume or residual volume before and after surgery. The total IPSS score increased significantly after surgery and at least 41 patients (68.3%) reported there was no change in one of the seven IPSS questions.
Laparoscopic LND with PANP was relatively safe in preserving urinary function.
PMCID: PMC3827062  PMID: 24265709
20.  Transgenerational Variations in DNA Methylation Induced by Drought Stress in Two Rice Varieties with Distinguished Difference to Drought Resistance 
PLoS ONE  2013;8(11):e80253.
Adverse environmental conditions have large impacts on plant growth and crop production. One of the crucial mechanisms that plants use in variable and stressful natural environments is gene expression modulation through epigenetic modification. In this study, two rice varieties with different drought resistance levels were cultivated under drought stress from tilling stage to seed filling stage for six successive generations. The variations in DNA methylation of the original generation (G0) and the sixth generation (G6) of these two varieties in normal condition (CK) and under drought stress (DT) at seedling stage were assessed by using Methylation Sensitive Amplification Polymorphism (MSAP) method. The results revealed that drought stress had a cumulative effect on the DNA methylation pattern of both varieties, but these two varieties had different responses to drought stress in DNA methylation. The DNA methylation levels of II-32B (sensitive) and Huhan-3 (resistant) were around 39% and 32%, respectively. Genome-wide DNA methylation variations among generations or treatments accounted for around 13.1% of total MSAP loci in II-32B, but was only approximately 1.3% in Huhan-3. In II-32B, 27.6% of total differentially methylated loci (DML) were directly induced by drought stress and 3.2% of total DML stably transmitted their changed DNA methylation status to the next generation. In Huhan-3, the numbers were 48.8% and 29.8%, respectively. Therefore, entrainment had greater effect on Huhan-3 than on II-32B. Sequence analysis revealed that the DML were widely distributed on all 12 rice chromosomes and that it mainly occurred on the gene’s promoter and exon region. Some genes with DML respond to environmental stresses. The inheritance of epigenetic variations induced by drought stress may provide a new way to develop drought resistant rice varieties.
PMCID: PMC3823650  PMID: 24244664
21.  Analyzing LC-MS/MS data by spectral count and ion abundance: two case studies 
Statistics and its interface  2012;5(1):75-87.
In comparative proteomics studies, LC-MS/MS data is generally quantified using one or both of two measures: the spectral count, derived from the identification of MS/MS spectra, or some measure of ion abundance derived from the LC-MS data. Here we contrast the performance of these measures and show that ion abundance is the more sensitive. We also examine how the conclusions of a comparative analysis are influenced by the manner in which the LC-MS/MS data is ‘rolled up’ to the protein level, and show that divergent conclusions obtained using different rollups can be informative. Our analysis is based on two publicly available reference data sets, BIATECH-54 and CPTAC, which were developed for the purpose of assessing methods used in label-free differential proteomic studies. We find that the use of the ion abundance measure reveals properties of both data sets not readily apparent using the spectral count.
PMCID: PMC3806317  PMID: 24163717
mass spectrometry; comparative proteomics; ion abundance; spectral count; ion competition
22.  Müllerian inhibiting substance is anterogradely transported and does not attenuate avulsion-induced death of hypoglossal motor neurons 
Experimental neurology  2010;231(2):304-308.
Müllerian Inhibiting Substance (MIS, Anti-Müllerian hormone) is a gonadal hormone that contributes to the subtle sex-biases in the nervous system. Mature neurons of both sexes also produce MIS, suggesting that MIS may be a paracrine regulator of adult neural networks. We report here that murine hypoglossal motor neurons produce MIS and its receptors, MISRII and bone morphogenetic protein receptor 1A (BMPR1A, ALK3), but differentially transport them, with only MIS being detectable in axons. The production of MIS and its receptors were rapidly down regulated after axonal damage, which is a characteristic of genes involved in mature neuronal function. MIS is a survival factor for embryonic spinal motor neurons, but the rate of cell loss after hypoglossal nerve avulsion was normal in Mis−/− mice and was not attenuated by intraventricular administration of MIS. These observations suggest that MIS may be involved in anterograde rather than autocrine or retrograde regulation of neurons.
PMCID: PMC3797533  PMID: 21195071
Axonal transport; Avulsion; MISRII; ALK3
23.  Mitochondrial DNA Coding and Control Region Variants as Genetic Risk Factors for Type 2 Diabetes 
Diabetes  2012;61(10):2642-2651.
Both the coding and control regions of mitochondrial DNA (mtDNA) play roles in the generation of diabetes; however, no studies have thoroughly reported on the combined diabetogenic effects of variants in the two regions. We determined the mitochondrial haplogroup and the mtDNA sequence of the control region in 859 subjects with diabetes and 1,151 normoglycemic control subjects. Full-length mtDNA sequences were conducted in 40 subjects harboring specific diabetes-related haplogroups. Multivariate logistic regression analysis with adjustment for age, sex, and BMI revealed that subjects harboring the mitochondrial haplogroup B4 have significant association with diabetes (DM) (odds ratio [OR], 1.54 [95% CI 1.18–2.02]; P < 0.001), whereas subjects harboring D4 have borderline resistance against DM generation (0.68 [0.49–0.94]; P = 0.02). Upon further study, we identified an mtDNA composite group susceptible to DM generation consisting of a 10398A allele at the coding region and a polycytosine variant at nucleotide pair 16184–16193 of the control region, as well as a resistant group consisting of C5178A, A10398G, and T152C variants. The OR for susceptible group is 1.31 (95% CI 1.04–1.67; P = 0.024) and for the resistant group is 0.48 (0.31–0.75; P = 0.001). Our study found that mtDNA variants in the coding and control regions can have combined effects influencing diabetes generation.
PMCID: PMC3447893  PMID: 22891220
24.  Self-compatibility in ‘Zaohong’ Japanese apricot is associated with the loss of function of pollen S genes 
Molecular Biology Reports  2013;40:6485-6493.
While most Japanese apricot (Prunus mume Sieb. et Zucc.) cultivars display typical S-RNase-based gametophytic self-incompatibility, some self-compatible (SC) cultivars have also been identified. In this study, we confirmed SC of ‘Zaohong’ through replicated self-pollination tests. Cross-pollination tests showed that SC of ‘Zaohong’ was caused by a loss of pollen function, so we determined that the S-genotype of ‘Zaohong’ was S2S15. Sequence analysis of the S-haplotypes of ‘Zaohong’ showed no mutations which were likely to alter gene function. Furthermore, expression analysis based on RT-PCR of S-locus genes revealed no differences at the transcript level when compared with ‘Xiyeqing’, a self-incompatible cultivar with the same S haplotypes. In addition, except for S-locus genes, a new type of F-box gene encoding a previously uncharacterised protein with high sequence similarity (61.03–64.65 %) to Prunus SFB genes was identified. Putative structural regions of PmF-box genes have been described, corresponding to regions in PmSFB alleles, but with some sequence variations. These results suggest that SC in ‘Zaohong’ occurs in pollen, and that other factors outside the S-locus, including PmF-box genes, might be associated with the loss of function of pollen S genes.
PMCID: PMC3824209  PMID: 24062077
Japanese apricot; Self-compatibility (compatible) (SC); Self-incompatibility (incompatible) (SI); S-RNase; SFB; PmF-box
25.  Serum proteomics analysis and comparisons using iTRAQ in the progression of hepatitis B 
The aim of this study was to analyze the changes in serum protein levels in the progression of hepatitis B using isobaric tags for relative and absolute quantitation (iTRAQ) analysis, in addition to comparing the serum protein levels of patients with chronic hepatitis B (CHB), patients with hepatitis B virus-induced acute-on-chronic liver failure (HBV-induced ACLF) and normal individuals. Protein analysis was performed on 15 serum samples using iTRAQ. The study population included healthy controls (n=5), patients with CHB (n=5) and patients with HBV-induced ACLF (n=5). Western blotting was used to verify the results in an additional nine serum samples from healthy controls, patients with CHB and patients with HBV-induced ACLF (n=3, respectively). Using iTRAQ analysis, 16 different serum proteins with ≥1.5-fold differences in expression levels were identified in the patients with CHB and ACLF compared with the healthy controls. Five of those proteins, C-reactive protein precursor, hemoglobin β chain variant Hb S-Wake, apolipoprotein J precursor, platelet factor 4 precursor and vitronectin, which demonstrated the greatest differences in their expression levels and the most significant correlation with liver diseases, were subsequently verified using western blotting. The western blotting results were consistent with the results from the iTRAQ. Two of the five proteins are not classified by biological process, and the biological functions of all the proteins in HBV-induced ACLF remain unclear. This preliminary study demonstrated that a correlation between the expression of various serum proteins and the different pathogenetic conditions induced by HBV may exist. The analysis of a larger number of samples is required to identify potential protein biomarkers that may be involved in the pathogenesis and progression of hepatitis B.
PMCID: PMC3820766  PMID: 24223640
serum; proteomics; isobaric tags for relative and absolute quantitation; hepatitis B

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