Xiao, Jun | Song, Can | Liu, Shaojun | Tao, Min | Hu, Jie | Wang, Jun | Liu, Wei | Zeng, Ming | Liu, Yun | Futscher, Bernard W.
Hybridization and polyploidization may lead to divergence in adaptation and boost speciation in angiosperms and some lower animals. Epigenetic change plays a significant role in the formation and adaptation of polyploidy. Studies of the effects of methylation on genomic recombination and gene expression in allopolyploid plants have achieved good progress. However, relevant advances in polyploid animals have been relatively slower. In the present study, we used the bisexual, fertile, genetically stable allotetraploid generated by hybridization of Carassius auratus red var. and Cyprinus carpio L. to investigate cytosine methylation level using methylation-sensitive amplification polymorphism (MSAP) analysis. We observed 38.31% of the methylation changes in the allotetraploid compared with the parents at 355 randomly selected CCGG sites. In terms of methylation status, these results indicate that the level of methylation modification in the allotetraploid may have increased relative to that in the parents. We also found that the major methylation changes were hypermethylation on some genomic fragments and genes related to metabolism or cell cycle regulation. These results provide circumstantial evidence that DNA methylation might be related to the gene expression and phenotype variation in allotetraploid hybrids. Our study partly fulfils the need for epigenetic research in polyploid animals, and provides evidence for the epigenetic regulation of allopolyploids.
doi:10.1371/journal.pone.0056409
PMCID: PMC3574156
PMID: 23457564
The potential of triethylenetetramine (TETA) to inhibit the oxidation of pyrite in H2SO4 solution had been investigated by using the open-circuit potential (OCP), cyclic voltammetry (CV), potentiodynamic polarization, and electrochemical impedance (EIS), respectively. Experimental results indicate that TETA is an efficient coating agent in preventing the oxidation of pyrite and that the inhibition efficiency is more pronounced with the increase of TETA. The data from potentiodynamic polarization show that the inhibition efficiency (η%) increases from 42.08% to 80.98% with the concentration of TETA increasing from 1% to 5%. These results are consistent with the measurement of EIS (43.09% to 82.55%). The information obtained from potentiodynamic polarization also displays that the TETA is a kind of mixed type inhibitor.
doi:10.1155/2013/387124
PMCID: PMC3569940
PMID: 23431501
Ye, Jian-Ning | Chen, Xing-Shu | Su, Le | Liu, Yun-Lai | Cai, Qi-Yan | Zhan, Xiao-Li | Xu, Yan | Zhao, Shi-Fu | Yao, Zhong-Xiang | Stangel, Martin
Demyelination occurs widely in neurodegenerative diseases. Progesterone has neuroprotective effects, is known to reduce the clinical scores and the inflammatory response. Progesterone also promotes remyelination in experimental autoimmune encephalomyelitis and cuprizone-induced demyelinating brain. However, it still remains unclear whether progesterone can alleviate neural behavioral deficits and demyelination with degeneration of oligodendroglial cells in cuprizone-induced mice. In this study, mice were fed with 0.2% cuprizone to induce demyelination, and treated with progesterone to test its potential protective effect on neural behavioral deficits, demyelination and degeneration of oligodendroglial cells. Our results showed noticeable alleviation of neural behavioral deficits following progesterone treatment as assessed by changes in average body weight, and activity during the open field and Rota-rod tests when compared with the vehicle treated cuprizone group. Progesterone treatment alleviated demyelination as shown by Luxol fast blue staining, MBP immunohistochemical staining, and electron microscopy. There was an obvious decrease in TUNEL and Caspase-3-positive apoptotic cells, and an increase in the number of oligodendroglial cells staining positive for PDGFRα, Olig2, Sox10 and CC-1 antibody in the brains of cuprizone-induced mice after progesterone administration. These results indicate that progesterone can alleviate neural behavioral deficits and demyelination against oligodendroglial cell degeneration in cuprizone-induced mice.
doi:10.1371/journal.pone.0054590
PMCID: PMC3554738
PMID: 23359803
Objectives
Endothelial progenitor cells (EPCs) can be used to repair tissues after myocardial infarction (MI) but EPC activators have adverse reactions. Rehmannia glutinosa is a herb used in traditional Chinese medicine, which can promote bone-marrow proliferation and protect the ischemic myocardium. We investigated the effects of Rehmannia glutinosa extract (RGE) on EPCs in a rat model of MI.
Methods
A total of 120 male Wistar rats were randomized to 2 groups (n = 60 each) for treatment: high-dose RGE (1.5 g·kg−1·day−1 orally) for 8 weeks, then left anterior descending coronary artery ligation, mock surgery or no treatment, then RGE orally for 4 weeks; or normal saline (NS) as the above protocol. The infarct region of the left ventricle was assessed by serial sectioning and morphology. EPCs were evaluated by number and function. Protein and mRNA levels of CD133, vascular endothelial growth factor receptor 2 (VEGFR2), chemokine C-X-C motif receptor 4 (CXCR4), stromal cell–derived factor-1α (SDF-1α) were measured by immunohistochemistry, Western blot and quantitative PCR analysis.
Results
RGE significantly improved left ventricular function, decreased the ischemic area and the apoptotic index in the infarct myocardium, also decreased the concentration of serum cardiac troponin T and brain natriuretic peptide at the chronic stage after MI (from week 2 to week 4). RGE increased EPC number, proliferation, migration and tube-formation capacity. It was able to up-regulate the expression of angiogenesis-associated ligand/receptor, including CD133, VEGFR2 and SDF-1α/CXCR4. In vitro, the effect of RGE on SDF-1α/CXCR4 cascade was reversed by the CXCR4 specific antagonist AMD3100.
Conclusion
RGE may enhance the mobilization, migration and therapeutic angiogenesis of EPCs after MI by activating the SDF-1α/CXCR4 cascade.
doi:10.1371/journal.pone.0054303
PMCID: PMC3548813
PMID: 23349848
Chu, Yen | Liu, Chien-Ying | Wu, Yi-Cheng | Hsieh, Ming-Ju | Chen, Tzu-Ping | Chao, Ying-Kai | Wu, Ching-Yang | Yuan, Hsu-Chia | Ko, Po-Jen | Liu, Yun-Hen | Liu, Hui-Ping | Yendamuri, Sai
Background
Natural orifice transluminal endoscopy has been developed for abdominal surgical procedures. The aim of this study was to compare the surgical outcome between a novel transoral approach and a standard transthoracic approach for the thoracic cavity in a canine model.
Methods
Twenty-eight dogs were assigned to transoral (n = 14) or standard thoracoscopy (n = 14). Each group underwent thoracic exploration, pre-determined surgical lung biopsy, and pericardial window creation. Blood draws were obtained before surgery and at postoperative days 1, 3, 7, and 14. Operative time, complications, laboratory parameters, hemodynamic parameters, and inflammatory parameters were compared between the two procedures. The animals were monitored for two weeks and necropsy were performed for surgical outcome evaluation.
Results
The thoracic procedures were successfully performed in all of the dogs, with the exception of one animal in the transoral group. There were no serious acute or delayed complications related to surgery. There was no difference between the two surgical groups for each of the hemodynamic parameters that were evaluated. Regarding the immunological impact of the surgeries, transoral thoracoscopy was associated with significant elevations in interleukin 6 and c-reactive protein levels on postoperative days 1 and 3, respectively, when compared with the standard thoracoscopy. All dogs recovered well, without signs of mediastinitis or thoracic infection. Necropsy revealed absence of infection, no injury to vital organs, and confirmed the success of the novel procedure.
Conclusions
This study suggests that both techniques were comparable with respect to procedure success rate, hemodynamic impact, and inflammatory changes. Furthermore, there was no difference in the incidence of postoperative discomfort between groups.
doi:10.1371/journal.pone.0050338
PMCID: PMC3536809
PMID: 23300944
Lin, Chan-Chan | Zhou, Jing-Ping | Liu, Yun-Peng | Liu, Jing-Jing | Yang, Xiao-Ning | Jazag, Amarsanaa | Zhang, Zhi-Ping | Guleng, Bayasi | Ren, Jian-Lin | Syn, Wing-Kin
Pokemon (POK erythroid myeloid ontogenic factor), which belongs to the POK protein family, is also called LRF, OCZF and FBI-1. As a transcriptional repressor, Pokemon assumes a critical function in cellular differentiation and oncogenesis. Our study identified an oncogenic role for Pokemon in human hepatocellular carcinoma (HCC). We successfully established human HepG2 and Huh-7 cell lines in which Pokemon was stably knocked down. We demonstrated that Pokemon silencing inhibited cell proliferation and migration. Pokemon knockdown inhibited the PI3K/Akt and c-Raf/MEK/ERK pathways and modulated the expression of various cell cycle regulators in HepG2 and Huh-7 cells. Therefore, Pokemon may also be involved in cell cycle progression in these cells. We confirmed that Pokemon silencing suppresses hepatocellular carcinoma growth in tumor xenograft mice. These results suggest that Pokemon promotes cell proliferation and migration in hepatocellular carcinoma and accelerates tumor development in an Akt- and ERK-signaling-dependent manner.
doi:10.1371/journal.pone.0051916
PMCID: PMC3530584
PMID: 23300578
Bulletin Board Systems (BBSs) have demonstrated their usefulness in spreading information. In BBS forums, a few posts that address currently popular social topics attract a lot of attention, and different users are interested in many different discussion topics. We investigate topic cluster features and user interests of an actual BBS forum, analyzing user posting and replying behavior. According to the growing process of BBS, we suggest a network model in which each agent only replies to the posts that belong to its specific topics of interest. A post that is replied to will be immediately assigned the highest priority on the post list. Simulation results show that characteristics of our model are similar to those of the real BBS. The model with heterogeneous user interests promotes the occurrence of popular posts, and the user relationship network possesses a large clustering coefficient. Bursts and long waiting time exist in user replying behavior, leading to non-Poisson user activity pattern. In addition, the model produces an analogous evolving trend of Gini coefficients for posts' and clusters' participants as BBS forums.
doi:10.1371/journal.pone.0050912
PMCID: PMC3521000
PMID: 23251401
The antitumor effects of 3,3′-diindolylmethane (DIM) are exhibited in a number of human cancer cells. However, there have been few studies performed concerning the effect of DIM on nasopharyngeal cancer (NPC) cells. In the present study, we examined the in vitro antitumor activity of DIM on the poorly differentiated NPC cell line CNE-2. The potential molecular mechanisms of the activity were also explored. CNE-2 cells were treated with varying concentrations of DIM for different times. Cell proliferation and apoptosis were detected and the molecular mechanisms involved in these effects were characterized. The results demonstrated that DIM at concentrations of 15–100 μM caused dose- and time-dependent inhibition of CNE-2 cell proliferation. Flow cytometry analysis revealed a high sub-G1 cell peak following treatment with DIM, and the rate of apoptosis increased. DIM may elevate the levels of cleaved Bid and Bax and enhance mitochondrial membrane depolarization, allowing the efflux of cytochrome c, Smac and Omi into the cytosol. The levels of caspases-3, -8 and -9 and cleaved poly (ADP-ribose) polymerase (PARP) were upregulated following DIM treatment in a dose-dependent manner. DIM also inhibits the phosphorylation of IκB-α, and showed dose-dependent inhibition of Bcl-2, XIAP and NF-κB in CNE-2 cells in vitro. These results indicate that DIM inhibits cell proliferation by inducing cell cycle arrest at G0/G1 phase and induces the apoptosis of CNE-2 cells by regulating multiple molecules in a mitochondria-dependent pathway. DIM may be a preventive and therapeutic agent against NPC.
doi:10.3892/ol.2012.1063
PMCID: PMC3573071
PMID: 23420395
3,3′-diindolylmethane; nasopharyngeal carcinoma; cell cycle arrest; apoptosis; mitochondria
In the title compound, C17H12ClNO2, the naphthoquinone system is essentially planar [maximum deviation = 0.078 (2) Å] and makes a dihedral angle of 52.38 (7)° with the benzene ring. The crystal structure features N—H⋯O interactions.
doi:10.1107/S1600536812045229
PMCID: PMC3588974
PMID: 23476210
Eukaryotic initiation factor (eIF)4E is over-expressed in many types of cancer such as breast, head and neck, and lung. A consequence of increased levels of eIF4E is the preferential translation of pro-tumorigenic proteins (e.g. c-Myc and vascular endothelial growth factor) and as a result is regarded as a potential therapeutic target. In this work a novel phage display peptide has been isolated against eIF4E. From the phage sequence two amino acids were delineated which improved binding when substituted into the eIF4G1 sequence. Neither of these substitutions were involved in direct interactions with eIF4E and acted either via optimization of the helical capping motif or restricting the conformational flexibility of the peptide. In contrast, substitutions of the remaining phage derived amino acids into the eIF4G1 sequence disrupted binding of the peptide to eIF4E. Interestingly when some of these disruptive substitutions were combined with key mutations from the phage peptide, they lead to improved affinities. Atomistic computer simulations revealed that the phage and the eIF4G1 derivative peptide sequences differ subtly in their interaction sites on eIF4E. This raises the issue, especially in the context of planar interaction sites such as those exhibited by eIF4E, that given the intricate plasticity of protein surfaces, the construction of structure-activity relationships should account for the possibility of significant movement in the spatial positioning of the peptide binding interface, including significant librational motions of the peptide.
doi:10.1371/journal.pone.0047235
PMCID: PMC3477164
PMID: 23094039
Zhang, Ye | Sun, Li-Ping | Xing, Cheng-Zhong | Xu, Qian | He, Cai-Yun | Li, Ping | Gong, Yue-Hua | Liu, Yun-Peng | Yuan, Yuan | Guan, Xin-Yuan
Glutathione S-transferase P1 (GSTP1) is a critical enzyme in the phase II detoxification pathway. One of the common functional polymorphisms of GSTP1 is A→G at nucleotide 313, which results in an amino acid substitution (Ile105Val) at the substrate binding site and reduced catalytic activity. We evaluated the interaction between GSTP1 Val allele and Helicobacter pylori infection, smoking and alcohol consumption, increasing the risk of gastric cancer among the Chinese population. Information on potential gastric cancer risk factors and blood specimens were collected from 618 incident gastric cancer cases and 1,830 non-cancer controls between March 2002 and December 2011 in Liaoning Province, China. GSTP1 Ile105Val was genotyped by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and polymerase chain reaction-restriction fragment length polymorphism. Serum levels of anti-H. pylori IgG were measured by ELISA. Odds ratio (OR) and 95% confidence interval (CI) were calculated using multivariate logistic regression, adjusted by sex and age. The risk of gastric cancer was significantly elevated in patients with the GSTP1 Val/Val genotype (adjusted OR = 3.324; 95% CI = 1.790–6.172). An elevated risk of gastric cancer was observed in patients with H. pylori infection, smoking, or alcohol consumption, and together with the GSTP1 Ile/Val +Val/Val genotype (OR = 3.696; 95% CI = 2.475–5.521; OR = 1.638; 95% CI = 1.044–2.571; OR = 1.641; 95% CI = 0.983–2.739, respectively) (p<0.05). The GSTP1 Val allele shows an interaction with smoking, alcohol consumption, and especially H. pylori infection for increasing the risk of gastric cancer. These findings could demonstrate new pathophysiological pathways for the development of gastric cancer.
doi:10.1371/journal.pone.0047178
PMCID: PMC3471930
PMID: 23077566
Tullin, Søren | Sams, Anette | Brandt, Jakob | Dahl, Kirsten | Gong, Wei | Jeppesen, Claus Bekker | Krogh, Thomas Nylandsted | Olsen, Grith Skytte | Liu, Yun | Pedersen, Anette Amstrup | Petersen, Jørn Meidahl | Rolin, Bidda | Wahlund, Per-Olof | Kalthoff, Christoph | Sanchez-Margalet, Victor
Aims/Hypothesis
Several studies have shown that adiponectin can lower blood glucose in diabetic mice. The aim of this study was to establish an effective adiponectin production process and to evaluate the anti-diabetic potential of the different adiponectin forms in diabetic mice and sand rats.
Methods
Human high molecular weight, mouse low molecular weight and mouse plus human globular adiponectin forms were expressed and purified from mammalian cells or yeast. The purified protein was administered at 10–30 mg/kg i.p. b.i.d. to diabetic db/db mice for 2 weeks. Furthermore, high molecular weight human and globular mouse adiponectin batches were administered at 5–15 mg/kg i.p. b.i.d. to diabetic sand rats for 12 days.
Results
Surprisingly, none of our batches had any effect on blood glucose, HbA1c, plasma lipids or body weight in diabetic db/db mice or sand rats. In vitro biological, biochemical and biophysical data suggest that the protein was correctly folded and biologically active.
Conclusions/Interpretation
Recombinant adiponectin is ineffective at lowering blood glucose in diabetic db/db mice or sand rats.
doi:10.1371/journal.pone.0044270
PMCID: PMC3462199
PMID: 23049674
In the title compound, C25H17NO4, the indolizine fused naphthaquinone unit is approximately planar [r.m.s deviation = 0.0678 Å] and makes a dihedral angle of 57.82 (5)° with the benzene ring of the methoxybenzene group. The naphthoquinone O atoms deviate, in the same sense, from the mean plane of the fused six-membered rings by 0.2001 (14) and 0.0516 (14) Å. In the crystal there is π–π stacking of inversion-related pairs of molecules [interplanar spacing = 3.514 (2) Å].
doi:10.1107/S1600536812040408
PMCID: PMC3470392
PMID: 23125805
Chemically modified graphite is an economical material with promising applications in its own right or as an intermediate in the synthesis of graphene. However, because of its extreme chemical inertness, to date only two methods—oxidation and fluorination—have been found which can modify graphite with high yield and large throughput. Herein, we describe a third chemical approach for the synthesis of large quantities of highly modified graphite which uses a microwave-sparks-assisted halogenation reaction. The resulting graphite halide can easily be exfoliated into monolayer graphene in organic solvents. The structure and electronic properties of the original graphene can be recovered after thermal annealing of the graphene halide. Furthermore, the graphene halide can be further modified by a variety of organic functional groups. Solution-processed field-effect transistors based on the graphene halides resulted in device performances were comparable to, or even better than, that of graphene oxide.
doi:10.1038/srep00662
PMCID: PMC3443813
PMID: 22993688
Pulmonary sclerosing hemangioma (PSH) is a rare benign tumor of the lungs. These tumors are composed of cuboidal surface cells and polygonal stromal cells and show four histological manifestations: hemorrhagic, papillary, solid, and sclerotic. PSH predominantly affects asymptomatic middle-aged women. The tumor often occurs at the intralobar site, and less commonly in the bronchus and mediastinum. PSH is easy to be misdiagnosed preoperatively. In this study, we present in detail the treatment procedures followed for two atypical cases of PSH. Case 1 was a 62-year-old woman bearing a tumor for 15 years. The tumor lesion was found to be located in the oblique fissure of the left lung. PSH was confirmed by surgical resection and postoperative pathological diagnosis. There was no sign of recurrence and metastasis 1.5 years after surgery. Case 2 was a 54-year-old woman diagnosed with bilateral multiple nodules by physical examination. This patient was diagnosed with definite PSH through computed tomography-guided percutaneous lung biopsy. Surgical resection was not performed. The patient also showed no sign of enlarged tumor and metastasis after 2 years of follow-up. Although PSH can be cured by surgical resection, the findings in our cases indicate that surgical resection need not be considered the preferred course of treatment. If PSH is diagnosed before surgery, the patients may survive while bearing the tumor.
doi:10.1186/1477-7819-10-182
PMCID: PMC3488534
PMID: 22943472
Pulmonary sclerosing hemangioma; Clinical; Surgical resection; Biopsy; Computed tomography,Pathology
doi:10.1038/cr.2011.95
PMCID: PMC3193480
PMID: 21647177
You, Xiaoqing | Zhang, Yun-wu | Chen, Yaomin | Huang, Xiumei | Xu, Raymond | Cao, Xihua | Chen, Jiebo | Liu, Yun | Zhang, Xiaokun | Xu, Huaxi
Alzheimer’s disease (AD) is characterized by the formation of extracellular senile plaques in the brain, whose major component is a small peptide called β-amyloid (Aβ). Long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) has been found beneficial for AD and several reports suggest that NSAIDs reduce the generation of Aβ, especially the more amyloidogenic form Aβ42. However, the exact mechanism underlying NSAIDs’ effect on AD risk remains largely inconclusive and all clinical trials using NSAIDs for AD treatment show negative results so far. Recent studies have shown that some NSAIDs can bind to certain nuclear receptors, suggesting that nuclear receptors may be involved in NSAID’s effect on AD risk. Here we find that (R)-flurbiprofen, the R-enantiomer of the racemate NSAID flurbiprofen, can significantly reduce Aβ secretion, but at the same time, increases the level of intracellular Aβ. In addition, we find that a nuclear receptor, retinoid X receptor α (RXRα), can regulate Aβ generation and that downregulation of RXRα significantly increases Aβ secretion. We also show that (R)-flurbiprofen can interfere with the interaction between RXRα and 9-cis-retinoid acid (9-cis-RA), and that 9-cis-RA decreases (R)-flurbiprofen’s reduction of Aβ secretion. Moreover, the modulation effect of (R)-flurbiprofen on Aβ is abolished upon RXRα downregulation. Together, these results suggest that RXRα can regulate Aβ generation and is also required for (R)-flurbiprofen-mediated Aβ generation.
doi:10.1111/j.1471-4159.2009.06312.x
PMCID: PMC3401643
PMID: 19659691
Aβ; Alzheimer’s disease; non-steroidal anti-inflammatory drug; (R)-flurbiprofen; retinoid X receptor α
AIM: To explore endoscopic therapy methods for gastric stromal tumors originating from the muscularis propria.
METHODS: For 69 cases diagnosed as gastric stromal tumors originating from the muscularis propria, three types of endoscopic therapy were selected, based on the size of the tumor. These methods included endoscopic ligation and resection (ELR), endoscopic submucosal excavation (ESE) and endoscopic full-thickness resection (EFR). The wound surface and the perforation of the gastric wall were closed with metal clips. Immunohistostaining for CD34, CD117, Dog-1, S-100 and smooth muscle actin (SMA) was performed on the resected tumors.
RESULTS: A total of 38 cases in which the tumor size was less than 1.2 cm were treated with ELR; three cases were complicated by perforation, and the perforations were closed with metal clips. Additionally, 18 cases in which the tumor size was more than 1.5 cm were treated with ESE, and no perforation occurred. Finally, 13 cases in which the tumor size was more than 2.0 cm were treated with EFR; all of the cases were complicated by artificial perforation, and all of the perforations were closed with metal clips. All of the 69 cases recovered with medical treatment, and none required surgical operation. Immunohistostaining demonstrated that among all of the 69 gastric stromal tumors diagnosed by gastroscopy, 12 cases were gastric leiomyomas (SMA-positive), and the other 57 cases were gastric stromal tumors.
CONCLUSION: Gastric stromal tumors originating from the muscularis propria can be treated successfully with endoscopic techniques, which could replace certain surgical operations and should be considered for further application.
doi:10.3748/wjg.v18.i26.3465
PMCID: PMC3396201
PMID: 22807618
Gastrointestinal stromal tumors; Therapy; Endoscopy; Muscularis propria; Resection
He, Weiguo | Qin, Qinbo | Liu, Shaojun | Li, Tangluo | Wang, Jing | Xiao, Jun | Xie, Lihua | Zhang, Chun | Liu, Yun | Michalak, Pawel
Through distant crossing, diploid, triploid and tetraploid hybrids of red crucian carp (Carassius auratus red var., RCC♀, Cyprininae, 2n = 100) × topmouth culter (Erythroculter ilishaeformis Bleeker, TC♂, Cultrinae, 2n = 48) were successfully produced. Diploid hybrids possessed 74 chromosomes with one set from RCC and one set from TC; triploid hybrids harbored 124 chromosomes with two sets from RCC and one set from TC; tetraploid hybrids had 148 chromosomes with two sets from RCC and two sets from TC. The 5S rDNA of the three different ploidy-level hybrids and their parents were sequenced and analyzed. There were three monomeric 5S rDNA classes (designated class I: 203 bp; class II: 340 bp; and class III: 477 bp) in RCC and two monomeric 5S rDNA classes (designated class IV: 188 bp, and class V: 286 bp) in TC. In the hybrid offspring, diploid hybrids inherited three 5S rDNA classes from their female parent (RCC) and only class IV from their male parent (TC). Triploid hybrids inherited class II and class III from their female parent (RCC) and class IV from their male parent (TC). Tetraploid hybrids gained class II and class III from their female parent (RCC), and generated a new 5S rDNA sequence (designated class I–N). The specific paternal 5S rDNA sequence of class V was not found in the hybrid offspring. Sequence analysis of 5S rDNA revealed the influence of hybridization and polyploidization on the organization and variation of 5S rDNA in fish. This is the first report on the coexistence in vertebrates of viable diploid, triploid and tetraploid hybrids produced by crossing parents with different chromosome numbers, and these new hybrids are novel specimens for studying the genomic variation in the first generation of interspecific hybrids, which has significance for evolution and fish genetics.
doi:10.1371/journal.pone.0038976
PMCID: PMC3377697
PMID: 22720007
Shen, Qin | Zhang, Zhou | Yu, Lan | Cao, Lan | Zhou, DaiZhan | Kan, MengYuan | Li, Baojie | Zhang, Di | He, Lin | Liu, Yun
A recent genome-wide association study has identified an association between leukocyte telomere length (LTL) and a locus at 3q26 that includes TERC. In order to evaluate the effects of the SNPs rs12696304 and rs16847897 near TERC in the population of mainland China, we conducted an association study of LTL focusing on these two candidate SNPs in a sample of 4016 Chinese Han individuals. Multiple linear regression analyses were performed to evaluate the association of LTL with each SNP adjusted for age, gender and diabetes status. In the study, we confirmed the association of SNP rs12696304 and rs16847897 near TERC with LTL in the Chinese Han population (P∼4.5 × 10−3 and 9.5 × 10−5, respectively). Each copy of the major allele of rs12696304 and rs16847897 was associated with a shorter mean telomere length of 0.024 and 0.031 T/S respectively, which is equivalent to about 3 and 4 years of average age-related telomere attrition. Our short report confirmed the effects of SNPs near TERC on LTL in the Chinese Han population for the first time.
doi:10.1038/ejhg.2011.4
PMCID: PMC3110055
PMID: 21304559
Chinese population; TERC; leukocyte telomere length
Background and Aims
The expression of the jumping translocation breakpoint (JTB) gene is upregulated in malignant liver tissues; however, JTB is associated with unbalanced translocations in many other types of cancer that suppress JTB expression. No comprehensive analysis on its function in human hepatocellular carcinoma (HCC) has been performed to date. We aimed to define the biological consequences for interaction between JTB and HBsAg in HCC cell lines.
Methods
We employed the stable transfection to establish small HBsAg expressing HepG2 cell line, and stably silenced the JTB expression using short hairpin RNA in HepG2 cell line. The effects of JTB and small HBsAg in vitro were determined by assessing cell apoptosis and motility.
Results
Silencing of JTB expression promoted cancer cell motility and reduced cell apoptosis, which was significantly enhanced by HBs expression. Expression of HBsAg inhibited the translocation of JTB to the mitochondria. Furthermore, silencing of the JTB resulted in an increase in the phosphorylation of p65 in HepG2 cells and HepG2-HBs cells, whereas HBsAg expression decreased the phosphorylation of p65. The silencing of JTB in HepG2-HBs cells conferred increased advantages in cell motility and anti-apoptosis.
Conclusion
HBsAg inhibited the translocation of JTB to the mitochondria and decreased the phosphorylation of p65 through the interaction with JTB, After JTB knockdown, HBsAg exhibited a stronger potential to promote tumor progression. Our data suggested that JTB act as a tumor suppressor gene in regards to HBV infection and its activation might be applied as a therapeutic strategy for in control of HBV related HCC development.
doi:10.1371/journal.pone.0036914
PMCID: PMC3352868
PMID: 22615844
Zhou, Jianyin | Zhao, Yilin | Wang, Jinling | Zhang, Sheng | Liu, Zhengjin | Zhen, Maochuan | Liu, Yun | Liu, Pingguo | Yin, Zhenyu | Wang, Xiaomin
Although therapeutic angiogenesis by angiogenic cytokines is a feasible strategy to improve regional blood flow in ischemic regions, the optimal delivery mode needs to be established. Here we designed a complex of collagen matrix (CM) and basic fibroblast growth factor (bFGF) and evaluated its proangiogenic effect in ischemic hindlimbs. The bFGF-CM was prepared using lyophilization. The morphology, porosity and toxicity of CM were examined. The bFGF releasing profile and bioactivity of released bFGF were assessed. bFGF-CM was intramuscularly implanted into the rabbit ischemic hindlimb model. Oxygen saturation parameters (OSP) of ischemic hindlimbs was measured to evaluate the extremity perfusion at intervals. Histological examination was performed to evaluate the level of angiogenesis. The CM and bFGF-CM were of identical multiporous structure lacking cytotoxicity. The releasing profile lasted 10 days and the released bFGF remained bioactive. OSP in bFGF-CM group was significantly higher
than that in CM, bFGF and ischemic groups at 2 and 4 weeks. The number of capillaries and mature vessels in bFGF-CM group were significantly greater than that in untreated control, CM and bFGF groups. Therefore, bFGF-CM enables the safe and effective long-term release of bFGF with improved angiogenesis in ischemic hindlimbs compared with CM devoid of bFGF.
doi:10.1100/2012/652794
PMCID: PMC3362026
PMID: 22666143
Objective
To analyze the changes in serum alkaline phosphatase (ALP) and bone alkaline phosphatase (BALP) activity and changes in osteocalcin (BGP) content following fluoride exposure and, thereby, determine the reference indications of fluoride-induced changes in bone metabolism.
Methods
In the animal study, rats were allowed free access to drinking water containing different concentrations (10, 150, or 400 mg/L) of sodium fluoride. Serum ALP and BALP activity and serum BGP content were assessed at three exposure time-points. In the spot study, serum ALP and BALP activity and serum BGP content were assessed in workers exposed to fluoride in their working environment for different periods of time.
Results
Compared with the control group, on days 15 and 30, the activity of serum ALP in the low- and medium-dose group was significantly higher (p < 0.05), while in the high-dose group it was significantly lower (p < 0.05). Only on day 30 was the activity of serum BALP in the medium-dose group significantly higher than that of the control group (p < 0.05). BGP content was lower in the high-dose group than in the control group (p < 0.05) on days 30 and 90, but it was higher in the medium-dose group on day 90. Compared with the control group, BGP content in the fluoride-exposed group was higher (p < 0.05). In the spot study, serum ALP activity and serum BGP content in the medium working-age group were higher than that in the short working-age group (p < 0.05). However, serum ALP activity and serum BGP content were lower in the long working-age group than in the medium working-age group (p < 0.05).
Conclusions
Our results suggest that serum fluoride and urinary fluoride can be used as reference indications to provide an overall reflection of the body’s fluoride-load and fluoride exposure level. Serum ALP activity and serum BGP content can be used as important reference indications for diagnosing bone metabolism changes resulting from fluoride exposure.
doi:10.1007/s12199-010-0181-y
PMCID: PMC3078298
PMID: 21431799
Sodium fluoride; Alkaline phosphatase; Bone alkaline phosphatase activity; Osteocalcium; Reference indications
Ralstonia solanacearum is a causal agent of plant bacterial wilt with thousands of distinct strains in a heterogeneous species complex. Here we report the genome sequence of a phylotype IB strain, Y45, isolated from tobacco (Nicotiana tabacum) in China. Compared with the published genomes of eight strains which were isolated from other hosts and habitats, 794 specific genes and many rearrangements/inversion events were identified in the tobacco strain, demonstrating that this strain represents an important node within the R. solanacearum complex.
doi:10.1128/JB.06009-11
PMCID: PMC3194909
PMID: 21994922
Hydrophobic monomers partially phase-separate from saturated lipids when loaded into lipid bilayers in amounts exceeding 1:1 monomer:lipid molar ratio. This conclusion is based on agreement between two independent methods of examining the structure of monomer-loaded bilayers. Complete phase separation of monomers from lipids would result in increase in bilayer thickness and slight increase in the diameter of liposomes. Homogeneous distribution of monomers within the bilayer would not change the bilayer thickness and would lead to the increase in the liposome diameter. The increase in bilayer thickness, measured by the combination of small angle neutron scattering (SANS) and small angle X-ray scattering (SAXS), was approximately one half of what was predicted for complete phase separation. The increase in liposome diameter, measured by dynamic light scattering (DLS), was in the middle between values predicted for homogeneous distribution and complete phase separation. Combined SANS, SAXS, and DLS data suggest that at 1.2 monomer:lipid ratio, approximately one half of monomers are located in an interstitial layer sandwiched between lipid sheets. These results expand our understanding of using self-assembled bilayers as scaffolds for directed covalent assembly of organic nanomaterials. In particular, partial phase separation of monomers from lipids corroborates successful creation of nanometer-thin polymer materials with uniform imprinted nanopores. Pore-forming templates do not need to span the lipid bilayer to create a pore in the bilayer-templated films.
doi:10.1021/la1050942
PMCID: PMC3097174
PMID: 21391646