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1.  The Efficacy of Chinese Herbal Medicine as an Adjunctive Therapy for Advanced Non-small Cell Lung Cancer: A Systematic Review and Meta-analysis 
PLoS ONE  2013;8(2):e57604.
Many published studies reflect the growing application of complementary and alternative medicine, particularly Chinese herbal medicine (CHM) use in combination with conventional cancer therapy for advanced non-small cell lung cancer (NSCLC), but its efficacy remains largely unexplored. The purpose of this study is to evaluate the efficacy of CHM combined with conventional chemotherapy (CT) in the treatment of advanced NSCLC. Publications in 11 electronic databases were extensively searched, and 24 trials were included for analysis. A sum of 2,109 patients was enrolled in these studies, at which 1,064 patients participated in CT combined CHM and 1,039 in CT (six patients dropped out and were not reported the group enrolled). Compared to using CT alone, CHM combined with CT significantly increase one-year survival rate (RR = 1.36, 95% CI = 1.15–1.60, p = 0.0003). Besides, the combined therapy significantly increased immediate tumor response (RR = 1.36, 95% CI = 1.19–1.56, p<1.0E−5) and improved Karnofsky performance score (KPS) (RR = 2.90, 95% CI = 1.62–5.18, p = 0.0003). Combined therapy remarkably reduced the nausea and vomiting at toxicity grade of III–IV (RR = 0.24, 95% CI = 0.12–0.50, p = 0.0001) and prevented the decline of hemoglobin and platelet in patients under CT at toxicity grade of I–IV (RR = 0.64, 95% CI = 0.51–0.80, p<0.0001). Moreover, the herbs that are frequently used in NSCLC patients were identified. This systematic review suggests that CHM as an adjuvant therapy can reduce CT toxicity, prolong survival rate, enhance immediate tumor response, and improve KPS in advanced NSCLC patients. However, due to the lack of large-scale randomized clinical trials in the included studies, further larger scale trials are needed.
doi:10.1371/journal.pone.0057604
PMCID: PMC3585199  PMID: 23469033
2.  Monolithic Composite “Pressure + Acceleration + Temperature + Infrared” Sensor Using a Versatile Single-Sided “SiN/Poly-Si/Al” Process-Module 
Sensors (Basel, Switzerland)  2013;13(1):1085-1101.
We report a newly developed design/fabrication module with low-cost single-sided “low-stress-silicon-nitride (LS-SiN)/polysilicon (poly-Si)/Al” process for monolithic integration of composite sensors for sensing-network-node applications. A front-side surface-/bulk-micromachining process on a conventional Si-substrate is developed, featuring a multifunctional SiN/poly-Si/Al layer design for diverse sensing functions. The first “pressure + acceleration + temperature + infrared” (PATIR) composite sensor with the chip size of 2.5 mm × 2.5 mm is demonstrated. Systematic theoretical design and analysis methods are developed. The diverse sensing components include a piezoresistive absolute-pressure sensor (up to 700 kPa, with a sensitivity of 49 mV/MPa under 3.3 V supplied voltage), a piezoresistive accelerometer (±10 g, with a sensitivity of 66 μV/g under 3.3 V and a −3 dB bandwidth of 780 Hz), a thermoelectric infrared detector (with a responsivity of 45 V/W and detectivity of 3.6 × 107 cm·Hz1/2/W) and a thermistor (−25–120 °C). This design/fabrication module concept enables a low-cost monolithically-integrated “multifunctional-library” technique. It can be utilized as a customizable tool for versatile application-specific requirements, which is very useful for small-size, low-cost, large-scale sensing-network node developments.
doi:10.3390/s130101085
PMCID: PMC3574723  PMID: 23325169
composite sensor; sensing networks; MEMS; single-sided; process
3.  Dry Needling at Myofascial Trigger Spots of Rabbit Skeletal Muscles Modulates the Biochemicals Associated with Pain, Inflammation, and Hypoxia 
Background and Purpose. Dry needling is an effective therapy for the treatment of pain associated with myofascial trigger point (MTrP). However, the biochemical effects of dry needling that are associated with pain, inflammation, and hypoxia are unclear. This study investigated the activities of β-endorphin, substance P, TNF-α, COX-2, HIF-1α, iNOS, and VEGF after different dosages of dry needling at the myofascial trigger spots (MTrSs) of a skeletal muscle in rabbit. Materials and Methods. Dry needling was performed either with one dosage (1D) or five dosages (5D) into the biceps femoris with MTrSs in New Zealand rabbits. Biceps femoris, serum, and dorsal root ganglion (DRG) were sampled immediately and 5 d after dry needling for β-endorphin, substance P, TNF-α, COX-2, HIF-1α, iNOS, and VEGF immunoassays. Results. The 1D treatment enhanced the β-endorphin levels in the biceps femoris and serum and reduced substance P in the biceps femoris and DRG. The 5D treatment reversed these effects and was accompanied by increase of TNF-α, COX-2, HIF-1α, iNOS, and VEGF production in the biceps femoris. Moreover, the higher levels of these biochemicals were still maintained 5 d after treatment. Conclusion. Dry needling at the MTrSs modulates various biochemicals associated with pain, inflammation, and hypoxia in a dose-dependent manner.
doi:10.1155/2012/342165
PMCID: PMC3544533  PMID: 23346198
4.  Simulation of the Fate and Seasonal Variations of α-Hexachlorocyclohexane in Lake Chaohu Using a Dynamic Fugacity Model 
The Scientific World Journal  2012;2012:691539.
Fate and seasonal variations of α-hexachlorocyclohexane (α-HCH) were simulated using a dynamic fugacity model in Lake Chaohu, China. Sensitivity analyses were performed to identify influential parameters and Monte Carlo simulation was conducted to assess model uncertainty. The calculated and measured values of the model were in good agreement except for suspended solids, which might be due to disregarding the plankton in water. The major source of α-HCH was an input from atmospheric advection, while the major environmental outputs were atmospheric advection and sediment degradation. The net annual input and output of α-HCH were approximately 0.294 t and 0.412 t, respectively. Sediment was an important sink for α-HCH. Seasonal patterns in various media were successfully modeled and factors leading to this seasonality were discussed. Sensitivity analysis found that parameters of source and degradation were more important than the other parameters. The sediment was influenced more by various parameters than air and water were. Temperature variation had a greater impact on the dynamics of the model output than other dynamic parameters. Uncertainty analysis showed that the model uncertainty was relatively low but significantly increased in the second half of the simulation period due to the increase in the gas-water diffusion flux variability.
doi:10.1100/2012/691539
PMCID: PMC3539339  PMID: 23365527
5.  Residues, Distributions, Sources, and Ecological Risks of OCPs in the Water from Lake Chaohu, China 
The Scientific World Journal  2012;2012:897697.
The levels of 18 organochlorine pesticides (OCPs) in the water from Lake Chaohu were measured by a solid phase extraction-gas chromatography-mass spectrometer detector. The spatial and temporal distribution, possible sources, and potential ecological risks of the OCPs were analyzed. The annual mean concentration for the OCPs in Lake Chaohu was 6.99 ng/L. Aldrin, HCHs, and DDTs accounted for large proportions of the OCPs. The spatial pollution followed the order of Central Lakes > Western Lakes > Eastern Lakes and water area. The sources of the HCHs were mainly from the historical usage of lindane. DDTs were degraded under aerobic conditions, and the main sources were from the use of technical DDTs. The ecological risks of 5 OCPs were assessed by the species sensitivity distribution (SSD) method in the order of heptachlor > γ-HCH > p,p′-DDT > aldrin > endrin. The combining risks of all sampling sites were MS > JC > ZM > TX, and those of different species were crustaceans > fish > insects and spiders. Overall, the ecological risks of OCP contaminants on aquatic animals were very low.
doi:10.1100/2012/897697
PMCID: PMC3515910  PMID: 23251107
6.  Levels, Temporal-Spatial Variations, and Sources of Organochlorine Pesticides in Ambient Air of Lake Chaohu, China 
The Scientific World Journal  2012;2012:504576.
The residual levels of OCPs in the gas phase and particle phase in Lake Chaohu, China, were measured using GC-MS from March 2010 to February 2011. The temporal-spatial variations and sources of OCPs were also analyzed. Twenty types of OCPs were detected in the gas phase with a total concentration of 484.8 ± 550.4 pg/m3. Endosulfan, DDTs and chlordane were the primary OCPs in the gas phase. The mean concentration of OCPs in the gas phase was significantly higher in the summer than in the winter. Seventeen types of OCPs were detected in the particle phase with a total concentration of 18.3 ± 26.1 pg/m3. DDTs were major OCPs in the particle phase. The mean concentration of OCPs in the particle phase decreased at first and then increased during the period. The potential source of the HCHs in ambient air of Lake Chaohu might come from recent lindane usage. DDTs mainly came from historical dicofol usage, and an input of DDT was observed in the spring, which may result from the present use of marine paint that contains technical DDT. Endosulfan and chlordane in the air may be due to the present use of technical endosulfan and chlordane.
doi:10.1100/2012/504576
PMCID: PMC3515905  PMID: 23251102
7.  Ribulokinase and Transcriptional Regulation of Arabinose Metabolism in Clostridium acetobutylicum 
Journal of Bacteriology  2012;194(5):1055-1064.
The transcription factor AraR controls utilization of l-arabinose in Bacillus subtilis. In this study, we combined a comparative genomic reconstruction of AraR regulons in nine Clostridium species with detailed experimental characterization of AraR-mediated regulation in Clostridium acetobutylicum. Based on the reconstructed AraR regulons, a novel ribulokinase, AraK, present in all analyzed Clostridium species was identified, which was a nonorthologous replacement of previously characterized ribulokinases. The predicted function of the araK gene was confirmed by inactivation of the araK gene in C. acetobutylicum and biochemical assays using purified recombinant AraK. In addition to the genes involved in arabinose utilization and arabinoside degradation, extension of the AraR regulon to the pentose phosphate pathway genes in several Clostridium species was revealed. The predicted AraR-binding sites in the C. acetobutylicum genome and the negative effect of l-arabinose on DNA-regulator complex formation were verified by in vitro binding assays. The predicted AraR-controlled genes in C. acetobutylicum were experimentally validated by testing gene expression patterns in both wild-type and araR-inactivated mutant strains during growth in the absence or presence of l-arabinose.
doi:10.1128/JB.06241-11
PMCID: PMC3294803  PMID: 22194461
8.  Pleiotropic functions of catabolite control protein CcpA in Butanol-producing Clostridium acetobutylicum 
BMC Genomics  2012;13:349.
Background
Clostridium acetobutylicum has been used to produce butanol in industry. Catabolite control protein A (CcpA), known to mediate carbon catabolite repression (CCR) in low GC gram-positive bacteria, has been identified and characterized in C. acetobutylicum by our previous work (Ren, C. et al. 2010, Metab Eng 12:446–54). To further dissect its regulatory function in C. acetobutylicum, CcpA was investigated using DNA microarray followed by phenotypic, genetic and biochemical validation.
Results
CcpA controls not only genes in carbon metabolism, but also those genes in solvent production and sporulation of the life cycle in C. acetobutylicum: i) CcpA directly repressed transcription of genes related to transport and metabolism of non-preferred carbon sources such as d-xylose and l-arabinose, and activated expression of genes responsible for d-glucose PTS system; ii) CcpA is involved in positive regulation of the key solventogenic operon sol (adhE1-ctfA-ctfB) and negative regulation of acidogenic gene bukII; and iii) transcriptional alterations were observed for several sporulation-related genes upon ccpA inactivation, which may account for the lower sporulation efficiency in the mutant, suggesting CcpA may be necessary for efficient sporulation of C. acetobutylicum, an important trait adversely affecting the solvent productivity.
Conclusions
This study provided insights to the pleiotropic functions that CcpA displayed in butanol-producing C. acetobutylicum. The information could be valuable for further dissecting its pleiotropic regulatory mechanism in C. acetobutylicum, and for genetic modification in order to obtain more effective butanol-producing Clostridium strains.
doi:10.1186/1471-2164-13-349
PMCID: PMC3507653  PMID: 22846451
CcpA; Pleiotropic regulator; Acidogenesis and solventogenesis; Sporulation
9.  A Lon-Like Protease with No ATP-Powered Unfolding Activity 
PLoS ONE  2012;7(7):e40226.
Lon proteases are a family of ATP-dependent proteases involved in protein quality control, with a unique proteolytic domain and an AAA+ (ATPases associated with various cellular activities) module accommodated within a single polypeptide chain. They were classified into two types as either the ubiquitous soluble LonA or membrane-inserted archaeal LonB. In addition to the energy-dependent forms, a number of medically and ecologically important groups of bacteria encode a third type of Lon-like proteins in which the conserved proteolytic domain is fused to a large N-terminal fragment lacking canonical AAA+ motifs. Here we showed that these Lon-like proteases formed a clade distinct from LonA and LonB. Characterization of one such Lon-like protease from Meiothermus taiwanensis indicated that it formed a hexameric assembly with a hollow chamber similar to LonA/B. The enzyme was devoid of ATPase activity but retained an ability to bind symmetrically six nucleotides per hexamer; accordingly, structure-based alignment suggested possible existence of a non-functional AAA-like domain. The enzyme degraded unstructured or unfolded protein and peptide substrates, but not well-folded proteins, in ATP-independent manner. These results highlight a new type of Lon proteases that may be involved in breakdown of excessive damage or unfolded proteins during stress conditions without consumption of energy.
doi:10.1371/journal.pone.0040226
PMCID: PMC3391209  PMID: 22792246
10.  Epithelial Cell Specificity and Apotope Recognition by Serum Autoantibodies in Primary Biliary Cirrhosis 
Hepatology (Baltimore, Md.)  2011;54(1):196-203.
A major enigma of primary biliary cirrhosis (PBC) is the selective targeting of biliary cells. Our laboratory has reported that following apoptosis human intrahepatic biliary epithelial cells (HiBEC) translocate the E2 subunit of the pyruvate dehydrogenase complex immunologically intact into apoptotic bodies, forming an apotope. However, the cell type and specificity of this reaction has not been fully defined. To address this issue we have investigated whether PDC-E2, BCOADC-E2, OGDC-E2, four additional inner mitochondrial enzymes and four nuclear antigens remain immunologically intact with respect to post-apoptotic translocation in HiBEC and 3 additional control epithelial cells. We report that all three 2-oxo acid dehydrogenase enzymes share the ability to remain intact within the apotope of HiBEC. Interestingly the E2 subunit of the branched chain 2-oxo acid dehydrogenase complex also remained intact in the other cell types tested. We extended the data using 95 AMA+ and 19 AMA- PBC and 76 control sera for reactivity against the 7 mitochondrial proteins studied herein and also the ability of AMA- sera to react with HIBEC apotopes. Sera from 3/95 AMA+ sera, but none of the controls, reacted with 2, 4-dienoyl CoA reductase 1 (DECR1), an enzyme also present intact only in the HiBEC apotope; DECR1 has not been previously associated with any autoimmune disease. Finally the specificity of HIBEC apotope reactivity was confined to AMA+ sera. In conclusion, we submit that the biliary specificity of PBC is secondary to the unique processes of biliary apoptosis.
doi:10.1002/hep.24355
PMCID: PMC3125447  PMID: 21488079
Apoptosis; human intrahepatic biliary epithelial cells; E2 subunit of 2-oxoacid dehydrogenase complex; nuclear antigens; autoimmunity
11.  Network Identification and Flux Quantification of Glucose Metabolism in Rhodobacter sphaeroides under Photoheterotrophic H2-Producing Conditions 
Journal of Bacteriology  2012;194(2):274-283.
The nonsulfur purple bacteria that exhibit unusual metabolic versatility can produce hydrogen gas (H2) using the electrons derived from metabolism of organic compounds during photoheterotrophic growth. Here, based on 13C tracer experiments, we identified the network of glucose metabolism and quantified intracellular carbon fluxes in Rhodobacter sphaeroides KD131 grown under H2-producing conditions. Moreover, we investigated how the intracellular fluxes in R. sphaeroides responded to knockout mutations in hydrogenase and poly-β-hydroxybutyrate synthase genes, which led to increased H2 yield. The relative contribution of the Entner-Doudoroff pathway and Calvin-Benson-Bassham cycle to glucose metabolism differed significantly in hydrogenase-deficient mutants, and this flux change contributed to the increased formation of the redox equivalent NADH. Disruption of hydrogenase and poly-β-hydroxybutyrate synthase resulted in a significantly increased flux through the phosphoenolpyruvate carboxykinase and a reduced flux through the malic enzyme. A remarkable increase in the flux through the tricarboxylic acid cycle, a major NADH producer, was observed for the mutant strains. The in vivo regulation of the tricarboxylic acid cycle flux in photoheterotrophic R. sphaeroides was discussed based on the measurements of in vitro enzyme activities and intracellular concentrations of NADH and NAD+. Overall, our results provide quantitative insights into how photoheterotrophic cells manipulate the metabolic network and redistribute intracellular fluxes to generate more electrons for increased H2 production.
doi:10.1128/JB.05624-11
PMCID: PMC3256653  PMID: 22056932
12.  Expression of Dickkopf-1 and Beta-Catenin Related to the Prognosis of Breast Cancer Patients with Triple Negative Phenotype 
PLoS ONE  2012;7(5):e37624.
Background and Aim
We investigated the prognostic importance of dickkopf-1(DKK1) and beta-catenin expression in triple negative breast cancers.
Methods
The expression of DKK1 and beta-catenin was evaluated in breast cell lines using RT-PCR and western blot. Immunohistochemistry was used to characterize the expression pattern of DKK1 and beta-catenin in 85 triple negative breast cancers and prognostic significance was assessed by Kaplan-Meier analysis and Cox proportional hazards regression modeling.
Results
The expression of DKK1 was confirmed in hormone-resistant breast cell lines MDA-MB-231, MDA-MB-231-HM and MDA-MB-435. Expression of DKK1 in triple negative breast cancers correlated with cytoplasmic/nuclear beta-catenin (p = 0.000). Elevated expression of DKK1 and cytoplasmic/nuclear beta-catenin in triple negative cancers indicate poor outcome of patients. DKK1 was also a prognostic factor for patients with earlier stage or no lymph node metastasis.
Conclusion
DKK1 together with beta-catenin might be important prognostic factors in triple negative breast carcinoma. DKK1 might be a valuable biomarker in predicting the prognosis of patients with earlier stage or no lymph node metastasis. It is possible that through further understanding of the role of Wnt/beta-catenin pathway activation, beta-catenin would be a potential therapeutic target for the triple negative breast cancer.
doi:10.1371/journal.pone.0037624
PMCID: PMC3359298  PMID: 22649545
13.  Evidence that RNA polymerase II and not TFIIB is responsible for the difference in transcription initiation patterns between Saccharomyces cerevisiae and Schizosaccharomyces pombe 
Nucleic Acids Research  2012;40(14):6495-6507.
The basal eukaryotic transcription machinery for protein coding genes is highly conserved from unicellular yeast to higher eukaryotes. Whereas TATA-containing promoters in human cells usually contain a single transcription start site (TSS) located ∼30 bp downstream of the TATA element, transcription in the yeast Schizosaccharomyces pombe and Saccharomyces cerevisiae typically initiates at multiple sites within a window ranging from 30 to 70 bp or 40 to 200 bp downstream of a TATA element, respectively. By exchanging highly purified factors between reconstituted S. pombe and S. cerevisiae transcription systems, we confirmed previous observations that the dual exchange of RNA polymerase II (RNAPII) and transcription factor IIB (TFIIB) confer the distinct initiation patterns between these yeast species. Surprisingly, however, further genetic and biochemical assays of TFIIB chimeras revealed that TFIIB and the proposed B-finger/reader domain do not play a role in determining the distinct initiation patterns between S. pombe and S. cerevisiae, but rather, these patterns are solely due to differences in RNAPII. These results are discussed within the context of a proposed model for the mechanistic coupling of the efficiency of early phosphodiester bond formation during productive TSS utilization and intrinsic elongation proficiency.
doi:10.1093/nar/gks323
PMCID: PMC3413132  PMID: 22510268
14.  Upregulation of fibronectin expression by COX-2 is mediated by interaction with ELMO1 
Cellular signalling  2010;23(1):99-104.
Engulfment and cell motility 1 (ELMO1), a bipartite guanine nucleotide exchange factor (GEF) for the small GTPase Rac 1, was identified as a susceptibility gene for glomerular disease. Here, we reported that ELMO1 interacted with COX-2 in human mesangial cells. Furthermore, we identified ELMO1 as a posttranslational regulator of COX-2 activity. We demonstrated that COX-2 cyclooxygenase activity increased fibronectin promoter activity. The protein-protein interaction between ELMO1 and COX-2 increased the cyclooxygenase activity of COX-2 and, correspondingly, fibronectin expression. We also found that ET625, the dominant negative form of ELMO1 lacking Rac1 activity, interacted with COX-2, increased cyclooxygenase activity of COX-2 and enhanced COX-2-mediated fibronectin upregulation. To further rule out Rac1 as an ELMO1-mediated regulator of COX-2 activity, we employed the constitutive active Rac1, Rac1Q63E, and demonstrated that Rac1 signaling has no effect on COX-2-mediated fibronectin promoter activity. These results suggest that ELMO1 contributes to the development of glomerular injury through serving as a regulator of COX-2 activity. The interaction of ELMO1 with COX-2 could play an important role in the development and progression of renal glomerular injury.
doi:10.1016/j.cellsig.2010.08.008
PMCID: PMC2956838  PMID: 20732417
15.  Smad7 siRNA inhibit expression of extracellular matrix in trabecular meshwork cells treated with TGF-β2 
Molecular Vision  2012;18:1881-1884.
Purpose
Extracellular matrix (ECM) deposits lead to elevated resistance of aqueous humor outflow which play an important role in the development of primary open angle glaucoma (POAG). The TGF-β2 (transforming growth factor β)/Smad (signaling mathers against decapentaplegic) pathway is known to regulate the ECM deposits. In this study, we determined the effect of Smad7 siRNA transfection in inhibiting the expression of ECM components.
Methods
Plasmid containing Smad7 siRNA was used to transfect cultured human trabecular meshwork cells (HTM). Protein expression of Smad7, fibronectin, and laminin was determined using western blot.
Results
Downregulation of Smad7 interrupts the effects of TGF-β2 on the expression of several ECM components. Smad7 siRNA can partially decrease the expression of Smad7, fibronectin, and laminin.
Conclusions
Smad7 plays an important role in regulating the ECM protein in the aqueous outflow pathway.
PMCID: PMC3413437  PMID: 22876112
16.  Oncometabolite 2-Hydroxyglutarate Is a Competitive Inhibitor of α-Ketoglutarate-Dependent Dioxygenases 
Cancer cell  2011;19(1):17-30.
SUMMARY
IDH1 and IDH2 mutations occur frequently in gliomas and acute myeloid leukemia, leading to simultaneous loss and gain of activities in the production of α-ketoglutarate (α-KG) and 2-hydroxyglutarate (2-HG), respectively. Here we demonstrate that 2-HG is a competitive inhibitor of multiple α-KG-dependent dioxygenases, including histone demethylases and the TET family of 5-methlycytosine (5mC) hydroxylases. 2-HG occupies the same space as α-KG does in the active site of histone demethylases. Ectopic expression of tumor-derived IDH1 and IDH2 mutants inhibits histone demethylation and 5mC hydroxylation. In glioma, IDH1 mutations are associated with increased histone methylation and decreased 5-hydroxylmethylcytosine (5hmC). Hence, tumor-derived IDH1 and IDH2 mutations reduce α-KG and accumulate an α-KG antagonist, 2-HG, leading to genome-wide histone and DNA methylation alterations.
doi:10.1016/j.ccr.2010.12.014
PMCID: PMC3229304  PMID: 21251613
17.  Fibroblastic Reticular Cells From Lymph Nodes Attenuate T Cell Expansion by Producing Nitric Oxide 
PLoS ONE  2011;6(11):e27618.
Adaptive immune responses are initiated when T cells encounter antigen on dendritic cells (DC) in T zones of secondary lymphoid organs. T zones contain a 3-dimensional scaffold of fibroblastic reticular cells (FRC) but currently it is unclear how FRC influence T cell activation. Here we report that FRC lines and ex vivo FRC inhibit T cell proliferation but not differentiation. FRC share this feature with fibroblasts from non-lymphoid tissues as well as mesenchymal stromal cells. We identified FRC as strong source of nitric oxide (NO) thereby directly dampening T cell expansion as well as reducing the T cell priming capacity of DC. The expression of inducible nitric oxide synthase (iNOS) was up-regulated in a subset of FRC by both DC-signals as well as interferon-γ produced by primed CD8+ T cells. Importantly, iNOS expression was induced during viral infection in vivo in both LN FRC and DC. As a consequence, the primary T cell response was found to be exaggerated in Inos−/− mice. Our findings highlight that in addition to their established positive roles in T cell responses FRC and DC cooperate in a negative feedback loop to attenuate T cell expansion during acute inflammation.
doi:10.1371/journal.pone.0027618
PMCID: PMC3215737  PMID: 22110693
18.  Metabolic engineering of the L-phenylalanine pathway in Escherichia coli for the production of S- or R-mandelic acid 
Background
Mandelic acid (MA), an important component in pharmaceutical syntheses, is currently produced exclusively via petrochemical processes. Growing concerns over the environment and fossil energy costs have inspired a quest to develop alternative routes to MA using renewable resources. Herein we report the first direct route to optically pure MA from glucose via genetic modification of the L-phenylalanine pathway in E. coli.
Results
The introduction of hydroxymandelate synthase (HmaS) from Amycolatopsis orientalis into E. coli led to a yield of 0.092 g/L S-MA. By combined deletion of competing pathways, further optimization of S-MA production was achieved, and the yield reached 0.74 g/L within 24 h. To produce R-MA, hydroxymandelate oxidase (Hmo) from Streptomyces coelicolor and D-mandelate dehydrogenase (DMD) from Rhodotorula graminis were co-expressed in an S-MA-producing strain, and the resulting strain was capable of producing 0.68 g/L R-MA. Finally, phenylpyruvate feeding experiments suggest that HmaS is a potential bottleneck to further improvement in yields.
Conclusions
We have constructed E. coli strains that successfully accomplished the production of S- and R-MA directly from glucose. Our work provides the first example of the completely fermentative production of S- and R-MA from renewable feedstock.
doi:10.1186/1475-2859-10-71
PMCID: PMC3182895  PMID: 21910908
Escherichia coli; fermentation; fine chemicals; metabolic engineering; renewable resources; R-mandelic acid; S-mandelic acid
19.  Germline Genetic Variants Disturbing the Let-7/LIN28 Double-Negative Feedback Loop Alter Breast Cancer Susceptibility 
PLoS Genetics  2011;7(9):e1002259.
Previous studies have shown that let-7 can repress the post-transcriptional translation of LIN28, and LIN28 in turn could block the maturation of let-7, forming a double-negative feedback loop. In this study, we investigated the effect of germline genetic variants on regulation of the homeostasis of the let-7/LIN28 loop and breast cancer risk. We initially demonstrated that the T/C variants of rs3811463, a single nucleotide polymorphism (SNP) located near the let-7 binding site in LIN28, could lead to differential regulation of LIN28 by let-7. Specifically, the C allele of rs3811463 weakened let-7–induced repression of LIN28 mRNA, resulting in increased production of LIN28 protein, which could in turn down-regulate the level of mature let-7. This effect was then validated at the tissue level in that the normal breast tissue of individuals with the rs3811463-TC genotype expressed significantly lower levels of let-7 and higher levels of LIN28 protein than those individuals with the rs3811463-TT genotype. Because previous in vitro and ex vivo experiments have consistently suggested that LIN28 could promote cellular transformation, we then systematically evaluated the relationship between rs3811463 as well as other common LIN28 SNPs and the risk of breast cancer in a stepwise manner. The first hospital-based association study (n = 2,300) demonstrated that two SNPs were significantly associated with breast cancer risk, one of which was rs3811463, while the other was rs6697410. The C allele of the rs3811463 SNP corresponded to an increased risk of breast cancer with an odds ratio (OR) of 1.25 (P = 0.0091), which was successfully replicated in a second independent study (n = 1,156) with community-based controls. The combined P-value of the two studies was 8.0×10−5. Taken together, our study demonstrates that host genetic variants could disturb the regulation of the let-7/LIN28 double-negative feedback loop and alter breast cancer risk.
Author Summary
Genetic variants are the genetic basis of inter-individual differences in susceptibility to common diseases like cancer. Single nucleotide polymorphisms (SNPs) are the major type of genetic variation in human beings, and previous studies have linked many SNPs with the risk of suffering human malignancies. In this study, we focused on microRNA (miRNA)–related SNPs and their relationship with the risk of breast cancer. MiRNAs are a kind of tiny endogenous RNAs that play important regulatory roles. Let-7 is a miRNA that has been proven to be capable of inhibiting the tumor occurrence. LIN28, a gene that promotes cancer, is a known regulator of let-7 and, interestingly, LIN28 itself is subject to repression by let-7. We have discovered that an SNP located near the target site of let-7 in LIN28 disturbs let-7's regulation of LIN28. This disturbance eventually leads to an increased level of LIN28 and a decreased level of let-7. We also, for the first time, confirmed that this SNP is associated with an increased risk of breast cancer in Han Chinese women. Our results suggest that genetic variants may potentially build a bridge from a physiological status to an aberrant, even pathological, status with the let-7/LIN28 loop in breast tissue, thus, facilitating carcinogenesis.
doi:10.1371/journal.pgen.1002259
PMCID: PMC3164678  PMID: 21912531
20.  Imported Measles and Implications for Its Elimination in Taiwan 
Emerging Infectious Diseases  2011;17(8):1523-1526.
During November 2008–May 2009, an outbreak of 53 measles cases occurred in Taiwan. Of these, 3 cases were sporadic, and the other 50 cases could be grouped into 8 clusters by genetic analysis. We determined 7 H1 genotypes linked to importation and 1 G3 genotype linked to an untraceable source.
doi:10.3201/eid1708.100800
PMCID: PMC3381574  PMID: 21801641
viruses; measles; Taiwan; nosocomial; measles outbreak; importation; dispatch
21.  Automated evaluation of electronic discharge notes to assess quality of care for cardiovascular diseases using Medical Language Extraction and Encoding System (MedLEE) 
The objective of this study was to develop and validate an automated acquisition system to assess quality of care (QC) measures for cardiovascular diseases. This system combining searching and retrieval algorithms was designed to extract QC measures from electronic discharge notes and to estimate the attainment rates to the current standards of care. It was developed on the patients with ST-segment elevation myocardial infarction and tested on the patients with unstable angina/non-ST-segment elevation myocardial infarction, both diseases sharing almost the same QC measures. The system was able to reach a reasonable agreement (κ value) with medical experts from 0.65 (early reperfusion rate) to 0.97 (β-blockers and lipid-lowering agents before discharge) for different QC measures in the test set, and then applied to evaluate QC in the patients who underwent coronary artery bypass grafting surgery. The result has validated a new tool to reliably extract QC measures for cardiovascular diseases.
doi:10.1136/jamia.2009.000182
PMCID: PMC2995708  PMID: 20442141
Quality of healthcare; information retrieval and extraction; knowledge acquisition (computer); myocardial infarction; coronary artery bypass grafting
22.  Improved methods for expression and purification of S. cerevisiae TFIIF and TFIIH; Identification of a functional E.coli promoter and internal translation initiation within the N-terminal coding region of the TFIIF TFG1 subunit 
The basal RNA polymerase II (RNAPII) transcription machinery is composed of RNAPII and the general transcription factors (TF) TATA binding protein (TBP), TFIIB, TFIIE, TFIIF and TFIIH. Due to the powerful genetic and molecular approaches that can be utilized, the budding yeast S. cerevisiae has proven to be an invaluable model system for studies of the mechanisms of RNAPII transcription. Complementary biochemical studies of the S. cerevisiae basal transcription machinery, however, have been hampered by difficulties in the purification of TFIIF and TFIIH, most notably due to the severe toxicity of the TFIIF Tfg1 subunit in E. coli and the complexity of the purification scheme for native TFIIH. Here, we report the elimination of TFG1-associated toxicity in E. coli, the identification and removal of a functional E.coli promoter and internal translation initiation within the N-terminal coding region of TFG1, and the efficient production and two step purification of recombinant TFIIF complexes. We also report conditions for the efficient two step tandem affinity purification (TAP) of holo-TFIIH, core TFIIH and TFIIK complexes from yeast whole cell extracts.
doi:10.1016/j.pep.2009.09.021
PMCID: PMC2827679  PMID: 19818408
S. cerevisiae; TFIIF; TFIIH; transcription
23.  The histone demethylase Dmel\Kdm4A controls genes required for lifespan and male-specific sex-determination in Drosophila 
Gene  2010;450(1-2):8-17.
Histone methylation plays an important role in regulating chromatin-mediated gene control and epigenetic-based memory systems that direct cell fate. Enzymes termed histone demethylases directly remove the methyl marks from histones, thus contributing to a dynamically regulated histone methylated genome, however the biological functions of these newly identified enzymes remains unclear. The JMJD2A-D family belongs to the JmjC domain-containing family of histone demethylases (JHDMs). Here, we report the cloning and functional characterization of the Drosophila HDM gene Dmel\Kdm4A that is a homolog of the human JMJD2 family. We show that homologs for three human JHDM families, JHDM1, JHDM2 and JMJD2 are present in Drosophila and that are each expressed during the Drosophila lifecycle. Disruption of Dmel\Kdm4A results in a reduction of the male lifespan and a male-specific wing extension/twitching phenotype that occurs in response to other males, and is reminiscent of an inter-male courtship phenotype involving the courtship song. Remarkably, certain genes associated with each of these phenotypes are significantly downregulated in response to Dmel\Kdm4A loss, most notably the longevity associated Hsp22 gene and the male sex-determination fruitless gene. Our results have implications for the role of the epigenetic regulator Dmel\Kdm4A in the control of genes involved in lifespan and male-specific sex-determination in the fly.
doi:10.1016/j.gene.2009.09.007
PMCID: PMC2795090  PMID: 19786080
24.  Enhancing mda-7/IL-24 therapy in renal carcinoma cells by inhibiting multiple protective signaling pathways using sorafenib and by Ad.5/3 gene delivery 
Cancer Biology & Therapy  2010;10(12):1290-1305.
We have determined whether an adenovirus that comprises the tail and shaft domains of a serotype 5 virus and the knob domain of a serotype 3 virus expressing MDA-7/IL-24, Ad.5/3-mda-7, more effectively infects and kills renal carcinoma cells (RCCs) compared to a serotype 5 virus, Ad.5-mda-7. RCCs are a tumor cell type that generally does not express the receptor for the type 5 adenovirus; the coxsakie and adenovirus receptor (CAR). Ad.5/3-mda-7 infected RCCs to a much greater degree than Ad.5-mda-7. MDA-7/IL-24 protein secreted from Ad.5/3-mda-7-infected RCCs induced MDA-7/IL-24 expression and promoted apoptosis in uninfected “bystander” RCCs. MDA-7/IL-24 killed both infected and bystander RCCs via CD95 activation. Knockdown of intracellular MDA-7/IL-24 in uninfected RCCs blocked the lethal effects of conditioned media. Infection of RCC tumors in one flank, with Ad.5/3-mda-7, suppressed growth of infected tumors and reduced the growth rate of uninfected tumors implanted on the opposite flank. The toxicity of the serotype 5/3 recombinant adenovirus to express MDA-7/IL-24 was enhanced by combined molecular or small molecule inhibition of MEK1/2 and PI3K; inhibition of mTOR, PI3K and MEK1/2; or use of the multi-kinase inhibitor sorafenib. In RCCs, combined inhibition of cytoprotective cell signaling pathways enhanced the MDA-7/IL-24-induction of CD95 activation, with greater mitochondrial dysfunction due to loss of MCL-1 and BCL-XL expression and tumor cell death. Treatment of RCC tumors in vivo with sorafenib also enhanced Ad.5/3-mda-7 toxicity and prolonged animal survival. Future combinations of these approaches hold promise for developing a more effective therapy for kidney cancer.
doi:10.4161/cbt.10.12.13497
PMCID: PMC3047088  PMID: 20948318
ERK; JNK; PI3K; AKT; MDA-7/IL-24; sorafenib; PERK; MAPK; interleukin; RCC; kidney
25.  Inhibition of MCL-1 in breast cancer cells promotes cell death in vitro and in vivo 
Cancer Biology & Therapy  2010;10(9):903-917.
The present studies have examined approaches to suppress MCL-1 function in breast cancer cells, as a means to promote tumor cell death. Treatment of breast cancer cells with CDK inhibitors (flavopiridol; roscovitine) enhanced the lethality of the ERBB1 inhibitor lapatinib in a synergistic fashion. CDK inhibitors interacted with lapatinib to reduce MCL-1 expression and overexpression of MCL-1 or knock down of BAX and BAK suppressed drug combination lethality. Lapatinib-mediated inhibition of ERK1/2 and to a lesser extent AKT facilitated CDK inhibitor-induced suppression of MCL-1 levels. Treatment of cells with the BH3 domain/MCL-1 inhibitor obatoclax enhanced the lethality of lapatinib in a synergistic fashion. Knock out of MCL-1 and BCL-XL enhanced lapatinib toxicity to a similar extent as obatoclax and suppressed the ability of obatoclax to promote lapatinib lethality. Pre-treatment of cells with lapatinib or with obatoclax enhanced basal levels of BAX and BAK activity and further enhanced drug combination toxicity. In vivo tumor growth data in xenograft and syngeneic model systems confirmed our in vitro findings. Treatment of cells with CDK inhibitors enhanced the lethality of obatoclax in a synergistic fashion. Overexpression of MCL-1 or knock down of BAX and BAK suppressed the toxic interaction between CDK inhibitors and obatoclax. Obatoclax and lapatinib treatment or obatoclax and CDK inhibitor treatment or lapatinib and CDK inhibitor treatment radiosensitized breast cancer cells. Lapatinib and obatoclax interacted to suppress mammary tumor growth in vivo. Collectively our data demonstrate that manipulation of MCL-1 protein expression by CDK inhibition or inhibition of MCL-1 sequestering function by Obatoclax renders breast cancer cells more susceptible to BAX/BAK-dependent mitochondrial dysfunction and tumor cell death.
doi:10.4161/cbt.10.9.13273
PMCID: PMC3040858  PMID: 20855960
MCL-1; Lapatinib; Obatoclax; Flavopiridol; Roscovitine; CDK inhibitor; RTK inhibitor; BCL-2 inhibitor; BAK

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