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1.  Hypochlorous acid via peroxynitrite activates protein kinase Cθ and insulin resistance in adipocytes 
We recently reported that genetic deletion of myeloperoxidase (MPO) alleviates obesity-related insulin resistance in mice in vivo. How MPO impairs insulin sensitivity in adipocytes is poorly characterized. As hypochlorous acid (HOCl) is a principal oxidant product generated by MPO, we evaluated the effects of HOCl on insulin signaling in adipocytes differentiated from 3T3-L1 cells. Exposure of 3T3-L1 adipocytes to exogenous HOCl (200 μmol/l) attenuated insulin-stimulated 2-deoxyglucose uptake, GLUT4 translocation, and insulin signals, including tyrosine phosphorylation of insulin receptor substrate 1 (IRS1) and phosphorylation of Akt. Furthermore, treatment with HOCl induced phosphorylation of IRS1 at serine 307, inhibitor κB kinase (IKK), c-Jun NH2-terminal kinase (JNK), and phosphorylation of PKCθ (PKCθ). In addition, genetic and pharmacological inhibition of IKK and JNK abolished serine phosphorylation of IRS1 and impairment of insulin signaling by HOCl. Furthermore, knockdown of PKCθ using siRNA transfection suppressed phosphorylation of IKK and JNK and consequently attenuated the HOCl-impaired insulin signaling pathway. Moreover, activation of PKCθ by peroxynitrite was accompanied by increased phosphorylation of IKK, JNK, and IRS1-serine 307. In contrast, ONOO− inhibitors abolished HOCl-induced phosphorylation of PKCθ, IKK, JNK, and IRS1-serine 307, as well as insulin resistance. Finally, high-fat diet (HFD)-induced insulin resistance was associated with enhanced phosphorylation of PKCθ, IKK, JNK, and IRS1 at serine 307 in white adipose tissues from WT mice, all of which were not found in Mpo knockout mice fed HFDs. We conclude that HOCl impairs insulin signaling pathway by increasing ONOO− mediated phosphorylation of PKCθ, resulting in phosphorylation of IKK/JNK and consequent serine phosphorylation of IRS1 in adipocytes.
doi:10.1530/JME-14-0213
PMCID: PMC4261204  PMID: 25381390
hypochlorous acid; insulin resistance; IRS1; peroxynitrite
2.  Bond cleavage, fragment modification and reassembly in enantioselective three-component reactions 
Nature Communications  2015;6:5801.
Chemical bond cleavage and reconstruction are common processes in traditional rearrangement reactions. In contrast, the process that involves bond cleavage, fragment modification and then reconstruction of the modified fragment provides an efficient way to build structurally diversified molecules. Here, we report a palladium(II)/chiral phosphoric acid catalysed three-component reaction of aryldiazoacetates, enamines and imines to afford α-amino-δ-oxo pentanoic acid derivatives in good yields with excellent diastereoselectivities and high enantioselectivities. The stereoselective reaction went through a unique process that involves cleavage of a C–N bond, modification of the resulting amino fragment and selective reassembly of the modified fragment. This innovative multi-component process represents a highly efficient way to build structurally diversified polyfunctional molecules in an atom and step economic fashion. A keto-iminium is proposed as a key intermediate and a chiral palladium/phosphate complex is proposed as an active catalyst.
Multi-component reactions allow complex structures to be rapidly built from simple starting materials. Here, the authors report an enantioselective three-component coupling of imines, enamines and aryldiazoacetates catalysed by a phosphinic acid and palladium(II).
doi:10.1038/ncomms6801
PMCID: PMC4309444  PMID: 25586817
3.  Effects of Adult Male Circumcision on Premature Ejaculation: Results from a Prospective Study in China 
BioMed Research International  2015;2015:417846.
The purpose of this study is to investigate the effects of adult male circumcision on premature ejaculation (PE). Therefore, between December 2009 and March 2014, a total of 575 circumcised men and 623 uncircumcised men (control group) were evaluated. Detailed evaluations (including circumcision and control groups) on PE were conducted before circumcision and at the 3-, 6-, 9-, and 12-month follow-up visits after circumcision. Self-estimated intravaginal ejaculatory latency time (IELT), Patient-Reported Outcome measures, and 5-item version of the International Index of Erectile Function were used to measure the ejaculatory and erectile function for all subjects. The results showed that, during the one-year follow-up, men after circumcision experienced higher IELT and better scores of control over ejaculation, satisfaction with sexual intercourse, and severity of PE than men before circumcision (P < 0.001 for all). Similarly, when compared with the control group, the circumcised men reported significantly improved IELT, control over ejaculation, and satisfaction with sexual intercourse (P < 0.001 for all). These findings suggested that circumcision might have positive effects on IELT, ejaculatory control, sexual satisfaction, and PE severity. In addition, circumcision was significantly associated with the development of PE.
doi:10.1155/2015/417846
PMCID: PMC4324807
4.  Quantitative survey of multiple CpGs from 5 genes identifies CpG methylation panel discriminating between high- and low-grade cervical intraepithelial neoplasia 
Clinical Epigenetics  2015;7(1):4.
Background
Studies of methylation biomarkers for cervical cancer often involved only few randomly selected CpGs per candidate gene analyzed by methylation-specific PCR-based methods, with often inconsistent results from different laboratories. We evaluated the role of different CpGs from multiple genes as methylation biomarkers for high-grade cervical intraepithelial neoplasia (CIN).
Results
We applied a mass spectrometry-based platform to survey the quantitative methylation levels of 34 CpG units from SOX1, PAX1, NKX6-1, LMX1A, and ONECUT1 genes in 100 cervical formalin-fixed paraffin-embedded (FFPE) tissues. We then used nonparametric statistics and Random Forest algorithm to rank significant CpG methylations and support vector machine with 10-fold cross validation and 200 times bootstrap resampling to build a predictive model separating CIN II/III from CIN I/normal subjects. We found only select CpG units showed significant differences in methylation between CIN II/III and CIN I/normal groups, while mean methylation levels per gene were similar between the two groups for each gene except PAX1. An optimal classification model involving five CpG units from SOX1, PAX1, NKX6-1, and LMX1A achieved 81.2% specificity, 80.4% sensitivity, and 80.8% accuracy.
Conclusions
Our study suggested that during CIN development, the methylation of CpGs within CpG islands is not uniform, with varying degrees of significance as biomarkers. Our study emphasizes the importance of not only methylated marker genes but also specific CpGs for identifying high-grade CINs. The 5-CpG classification model provides a promising biomarker panel for the early detection of cervical cancer.
Electronic supplementary material
The online version of this article (doi:10.1186/s13148-014-0037-1) contains supplementary material, which is available to authorized users.
doi:10.1186/s13148-014-0037-1
PMCID: PMC4334603
Cervical cancer; Cervical intraepithelial neoplasia (CIN); DNA methylation; High-grade CIN; Biomarkers
5.  RhoC, vascular endothelial growth factor and microvascular density in esophageal squamous cell carcinoma 
AIM: To investigate the expression of Ras homolog (Rho)C, vascular endothelial growth factor (VEGF) and CD105 in esophageal squamous cell carcinoma.
METHODS: Semi-quantitative reverse transcriptase polymerase chain reaction, in situ hybridization and immunohistochemical streptavidin-biotin- peroxidase methods were used to detect expression of RhoC mRNA and protein, and VEGF protein in 62 cases with esophageal squamous cell carcinoma, 31 cases with adjacent atypical hyperplastic tissues, and 62 cases with normal esophageal mucosa. CD105 antibody labeling was used to measure microvascular density. Expression levels were compared according to clinicopathologic and patient parameters.
RESULTS: Expression of RhoC mRNA showed a positive correlation with the protein level in esophageal squamous cell carcinoma, as well as with VEGF protein levels. RhoC mRNA expression was mainly located within the cytoplasm of the tumor cells, appearing as blue to purple particles by in situ hybridization. The differences in RhoC mRNA expression in esophageal squamous cell carcinoma, adjacent atypical hyperplasia and normal esophageal mucosa were significant (P < 0.05). The relative expression of RhoC mRNA in cancer tissues with lymph node metastasis was significantly higher than in the tissues without lymph node metastasis (P < 0.05). VEGF protein expression was consistent with microvascular density (t = 25.52, P < 0.05). Positive expression of VEGF protein in esophageal squamous cell carcinoma of different histologic gradings did not differ significantly. Positive expression of VEGF protein in carcinoma tissues with deep infiltration was significantly higher than in tissues with only superficial infiltration (P < 0.05). The positive expression of VEGF protein in cancer tissues with lymph node metastasis was significantly higher than in the tissues without lymph node metastasis (P < 0.05).
CONCLUSION: RhoC protein may upregulate VEGF expression, thereby promoting tumor angiogenesis. RhoC mRNA and protein expression was correlated with metastasis.
doi:10.3748/wjg.v21.i3.905
PMCID: PMC4299343  PMID: 25624724
Esophageal squamous cell carcinoma; Gene silencing; Ras homolog C; Vascular endothelial growth factor
6.  A nationwide telepathology consultation and quality control program in China: implementation and result analysis 
Diagnostic Pathology  2014;9(Suppl 1):S2.
Background
Telepathology may play an important role in pathology consultation and quality control for cancer diagnosis in China, as the country has the largest population of cancer patients worldwide. In 2011, the Pathology Quality Control Center of China and Ministry of Health developed and implemented a nationwide telepathology consultation and quality control program for cancer diagnosis in China. We here report the results of the two-year implementation and experiences.
Methods
the program built an Internet based telepathology platform to connect participating hospitals and expert consultants. The hardware and software used for the platform were validated in previous validation studies in China. The program had three regional centers consisting of Peking Union Medical College, Huasi Medical College of Sichuan and 2nd affiliated hospital of Zhejiang University. It also had 20 provincial consultation centers based in the provincial referral hospitals. 80 provincial or national pathologists served as expert consultants for the program, providing telepathology consultation for cancer diagnosis for more than 60 participating hospitals.
Results
from 2011 to July 2013, 16,247 pathology cases were submitted to the platform for consultation. Among them, 84% were due to diagnostic difficulty and 16% were due to request by patients. The preliminary diagnosis provided by submitting pathologists were in agreement with expert opinion in 59.8% of cases but was in disagreement with expert opinion in 24.2% of cases. 16.0% of cases were not provided with preliminary diagnosis. The distribution of pathology cases by system or organ were: digestive system, 17.3%; gynecologic system, 16.7%; head and neck, 15.7%; bone and soft tissue, 10.4%; lung and mediastinum, 8.6%; breast, 7.6%; urinary system, 7.5%; hematopathology, 6.4%; skin, 5.2%; neuropathology, 2.5% and cytopathology, 1.3%. Expert consultants also provided assessment of quality of slide preparation and staining, online lectures and guidance for pathology quality control.
Conclusion
our results of two years' implementation indicated that telepathology could solve the problem of uneven distribution of pathology resources and provide a solution for countrywide pathology quality control in China. Telepathology could play an important role in improving pathology diagnosis in China.
doi:10.1186/1746-1596-9-S1-S2
PMCID: PMC4305972  PMID: 25565398
9.  Selenium and diabetes - evidence from animal studies 
Free radical biology & medicine  2013;65:10.1016/j.freeradbiomed.2013.07.012.
Whereas selenium was found to act as an insulin-mimic and to be anti-diabetic in earlier studies, recent animal experiments and human trials have shown unexpected risk of prolonged high Se intake in potentiating insulin resistance and type 2 diabetes. Elevating dietary Se intakes (0.4 to 3.0 mg/kg of diet) above the nutrient requirements, similar to overproduction of selenoproteins, led to insulin resistance and(or) diabetes-like phenotypes in mice, rats, and pigs. Although its diabetogenic mechanism remains unclear, the high Se intake elevated activity or production of selenoproteins including GPx1, MsrB1, SelS, and SelP. This up-regulation diminished intracellular reactive oxygen species (ROS) and then dys-regulated key regulators of β cells and insulin synthesis and secretion, leading to chronic hyperinsulinaemia. Over-scavenging intracellular H2O2 also attenuated oxidative inhibition of protein tyrosine phosphatases and suppressed insulin signaling. High Se intake might affect expression and(or) function of key regulators for glycolysis, gluconeogenesis, and lipogenesis. Future research is needed to find out if certain forms of Se metabolites in addition to selenoproteins and if mechanisms other than intracellular redox control mediate the diabetogenic effect of high Se intakes. Furthermore, a potential interactive role of high Se intakes in the interphase of carcinogenesis and diabetogenesis should be explored to make the optimal use of Se in human nutrition and health.
doi:10.1016/j.freeradbiomed.2013.07.012
PMCID: PMC3859733  PMID: 23867154
Diabetes; Insulin; Reactive oxygen species; Selenium; Selenoprotein
10.  Cryo-Electron Microscopy Study of Insect Cell-Expressed Enterovirus 71 and Coxsackievirus A16 Virus-Like Particles Provides a Structural Basis for Vaccine Development 
Journal of Virology  2014;88(11):6444-6452.
ABSTRACT
Enterovirus 71 (EV71) and coxsackievirus A16 (CA16) are the two most common etiological agents responsible for the epidemics of hand, foot, and mouth disease (HFMD), a childhood illness with occasional severe neurological complications. A number of vaccine candidates against EV71 or CA16 have been reported; however, no vaccine is currently available for clinical use. Here, we generated a secreted version of EV71 and CA16 virus-like particles (VLPs) using a baculovirus-insect cell expression system and reconstructed the three-dimensional (3D) structures of both VLPs by cryo-electron microscopy (cryo-EM) single-particle analysis at 5.2-Å and 5.5-Å resolutions, respectively. The reconstruction results showed that the cryo-EM structures of EV71 and CA16 VLPs highly resemble the recently published crystal structures for EV71 natural empty particles and CA16 135S-like expanded particles, respectively. Our cryo-EM analysis also revealed that the majority of previously identified linear neutralizing epitopes are well preserved on the surface of EV71 and CA16 VLPs. In addition, both VLPs were able to induce efficiently neutralizing antibodies against various strains of EV71 and CA16 viruses in mouse immunization. These studies provide a structural basis for the development of insect cell-expressed VLP vaccines and for a potential bivalent VLP vaccine against both EV71- and CA16-associated HFMD.
IMPORTANCE The recent outbreaks of hand, foot, and mouth disease (HFMD) in the Asia Pacific region spurred the search for effective vaccines against EV71 and CA16 viruses, the two most common etiological agents responsible for HFMD. In this paper, we show that secreted versions of EV71 and CA16 VLPs generated in the baculovirus-insect cell expression system highly resemble the crystal structures of their viral conterparts and that the majority of previously identified linear neutralizing epitopes are well preserved on the VLP surfaces. In addition, the generated VLPs can efficiently induce neutralizing antibodies against various strains of EV71 and CA16 viruses in mouse immunization. These studies provide a structural basis for the development of insect cell-expressed VLP vaccines and for a potential bivalent VLP vaccine against both EV71- and CA16-associated HFMD.
doi:10.1128/JVI.00200-14
PMCID: PMC4093858  PMID: 24672036
11.  Primary malignant neuroectodermal tumor of the ileum with predominantly uncommon pseudopapillary architecture 
A malignant gastrointestinal neuroectodermal tumor (GNET), a distinctive entity covering the characteristics of clear cell sarcoma (CCS) of gastrointestinal tract described recently, arising primarily in the ileum of a 33-year-old woman is reported. Histologically, the neoplasm involved the full thickness of the intestinal wall. Tumor cells, mainly displayed epithelioid or polygonal appearance with oval or round nuclei, arranged in strand, nested, and solid pattern with prominent pseudopapillary architecture instead of the familiar histological image with multinucleated osteoclast-like giant cells. They were positive for vimentin, S-100, synaptophysin, CD56 and CD99 protein, but negative for AE1/AE3, EMA, CEA, LCA, Desmin, CK7, CK20, Villin, CgA, CD117, Dog-1, GFAP, Melan-A, HMB-45, CD34, CR, WT1, D2-40. Fluorescence in situ hybridization (FISH) showed the presence of chromosomal translocation involving EWSR. The patients lived through a calm period after a tumor resection and 4 cycles of chemotherapy combining ifosfamide and epirubicin. This case demonstrates that GNET is a rare tumor in gastrointestinal tract, and furthermore, various misleading histological characteristics should been taken into consideration in the diagnosis.
PMCID: PMC4313982
Malignant gastrointestinal neuroectodermal tumor; clear cell sarcoma; ileum; pseudopapillary; immunochemistry; FISH
12.  Reduced Expression of PTPRD Correlates with Poor Prognosis in Gastric Adenocarcinoma 
PLoS ONE  2014;9(11):e113754.
Background
PTPRD, encoding protein tyrosine phosphatases receptor type D, is located at chromosome 9p23–24.1, a loci frequently lost in many types of tumors. Recently, PTPRD has been proposed to function as a tumor suppressor gene. The current study aimed to investigate PTPRD expression and its prognostic significance in primary gastric adenocarcinoma.
Methods and Results
Quantitative real time reverse transcription PCR (qRT-PCR) and western blotting were used to examine PTPRD expression in paired gastric tumourous and paracancerous tissues. Compared with the matched normal gastric mucosa tissues, both the mRNA (P = 0.0138) and protein (P = 0.0093) expression of PTPRD in fresh surgical specimens were significantly reduced. Clinicopathological and prognostic roles of PTPRD in gastric adenocarcinoma were investigated using immunohistochemistry with 513 paraffin-embedded gastric adenocarcinoma tissue blocks. Statistical analysis revealed that reduced PTPRD expression was significantly associated with T stage (P = 0.004), TNM stage (P<0.001) and tumor size (P = 0.003). Furthermore, Kaplan-Meier survival analysis revealed that low expression of PTPRD significantly correlated with poor survival of gastric cancer patients (P<0.001). Cox regression analysis confirmed PTPRD expression as independent predictor of the overall survival of gastric cancer patients. The MTT assay determined the effects of PTPRD on cell proliferation of MGC803 and GES1 cell lines. Restoring PTPRD expression in MGC803 cells significantly inhibited their growth rate. Silencing PTPRD expression by siRNA treatment in GES1 significantly enhanced cell proliferation compared with mock siRNA treatment. Methylation analysis of PTPRD promoter CpG island in 3 primary GC samples showed one case with partial methylation.
Conclusions
These results indicated that PTPRD is a candidate tumour suppressor in gastric cancer. Thus, PTPRD may play an important role in gastric tumorigenesis and serve as a valuable prognostic marker of gastric adenocarcinoma.
doi:10.1371/journal.pone.0113754
PMCID: PMC4239117  PMID: 25412184
13.  Role of PET/CT in the diagnosis, staging, and follow-up of a nasal-type natural killer T-cell lymphoma in the larynx: a case report and literature review 
Background: Nasal-type natural killer T-cell lymphoma involving the larynx is uncommon. Our search revealed only 12 cases reported previously in the English-language literature. Case report: We report a case of laryngeal NKTCL. In December 2011, the patient was diagnosed with nasal-type NKTCL and FDG PET/CT showed the lesions were confined to the nasal cavity (stage I). At 1 year after radiotherapy, the patient presented with hoarseness and FDG PET/CT revealed high FDG uptake in the subglottic region and left cervical lymph nodes. A biopsy of the subglottis confirmed NKTCL (stage II). He then received chemotherapy and 14 months after the completion of chemotherapy, FDG PET/CT showed no evidence of recurrence or metastasis. Conclusions: PET/CT has better sensitivity than other conventional methods and may play an important role in the diagnosis, staging, and follow-up of nasal-type natural killer T-cell lymphoma.
PMCID: PMC4276232  PMID: 25550974
Natural killer T-cell lymphoma; larynx; PET/CT; follow-up
14.  Noninvasive Molecular Imaging of Cell Death in Myocardial Infarction using 111In-GSAO 
Scientific Reports  2014;4:6826.
Acute insult to the myocardium is associated with substantial loss of cardiomyocytes during the process of myocardial infarction. In this setting, apoptosis (programmed cell death) and necrosis may operate on a continuum. Because the latter is characterized by the loss of sarcolemmal integrity, we propose that an appropriately labeled tracer directed at a ubiquitously present intracellular moiety would allow non-invasive definition of cardiomyocyte necrosis. A trivalent arsenic peptide, GSAO (4-(N-(S-glutathionylacetyl)amino)phenylarsonous acid), is capable of binding to intracellular dithiol molecules such as HSP90 and filamin-A. Since GSAO is membrane impermeable and dithiol molecules abundantly present intracellularly, we propose that myocardial localization would represent sarcolemmal disruption or necrotic cell death. In rabbit and mouse models of myocardial infarction and post-infarct heart failure, we employed In-111-labelled GSAO for noninvasive radionuclide molecular imaging. 111In-GSAO uptake was observed within the regions of apoptosis seeking agent- 99mTc-Annexin A5 uptake, suggesting the colocalization of apoptotic and necrotic cell death processes.
doi:10.1038/srep06826
PMCID: PMC4212241  PMID: 25351258
15.  HDAC6 Deacetylase Activity Is Critical for Lipopolysaccharide-Induced Activation of Macrophages 
PLoS ONE  2014;9(10):e110718.
Activated macrophages play an important role in both innate and adaptive immune responses, and aberrant activation of macrophages often leads to inflammatory and immune disorders. However, the molecular mechanisms of how macrophages are activated are not fully understood. In this study, we identify a novel role for histone deacetylse 6 (HDAC6) in lipopolysaccharide (LPS)-induced macrophage activation. Our data show that suppression of HDAC6 activity significantly restrains LPS-induced activation of macrophages and production of pro-inflammatory cytokines. Further study reveals that the regulation of macrophage activation by HDAC6 is independent of F-actin polymerization and filopodium formation; instead, it is mediated by the effects of HDAC6 on cell adhesion and microtubule acetylation. These data thus suggest that HDAC6 is an important regulator of LPS-induced macrophage activation and might be a potential target for the management of inflammatory disorders.
doi:10.1371/journal.pone.0110718
PMCID: PMC4199742  PMID: 25330030
16.  Proteomic identification and functional characterization of MYH9, Hsc70, and DNAJA1 as novel substrates of HDAC6 deacetylase activity 
Protein & Cell  2014;6(1):42-54.
ABSTRACT
Histone deacetylase 6 (HDAC6), a predominantly cytoplasmic protein deacetylase, participates in a wide range of cellular processes through its deacetylase activity. However, the diverse functions of HDAC6 cannot be fully elucidated with its known substrates. In an attempt to explore the substrate diversity of HDAC6, we performed quantitative proteomic analyses to monitor changes in the abundance of protein lysine acetylation in response to HDAC6 deficiency. We identified 107 proteins with elevated acetylation in the liver of HDAC6 knockout mice. Three cytoplasmic proteins, including myosin heavy chain 9 (MYH9), heat shock cognate protein 70 (Hsc70), and dnaJ homolog subfamily A member 1 (DNAJA1), were verified to interact with HDAC6. The acetylation levels of these proteins were negatively regulated by HDAC6 both in the mouse liver and in cultured cells. Functional studies reveal that HDAC6-mediated deacetylation modulates the actin-binding ability of MYH9 and the interaction between Hsc70 and DNAJA1. These findings consolidate the notion that HDAC6 serves as a critical regulator of protein acetylation with the capability of coordinating various cellular functions.
Electronic supplementary material
The online version of this article (doi:10.1007/s13238-014-0102-8) contains supplementary material, which is available to authorized users.
doi:10.1007/s13238-014-0102-8
PMCID: PMC4286133  PMID: 25311840
HDAC6; substrate; lysine acetylation; quantitative proteomics; interaction
17.  Proteomic identification and functional characterization of MYH9, Hsc70, and DNAJA1 as novel substrates of HDAC6 deacetylase activity 
Protein & Cell  2014;6(1):42-54.
ABSTRACT
Histone deacetylase 6 (HDAC6), a predominantly cytoplasmic protein deacetylase, participates in a wide range of cellular processes through its deacetylase activity. However, the diverse functions of HDAC6 cannot be fully elucidated with its known substrates. In an attempt to explore the substrate diversity of HDAC6, we performed quantitative proteomic analyses to monitor changes in the abundance of protein lysine acetylation in response to HDAC6 deficiency. We identified 107 proteins with elevated acetylation in the liver of HDAC6 knockout mice. Three cytoplasmic proteins, including myosin heavy chain 9 (MYH9), heat shock cognate protein 70 (Hsc70), and dnaJ homolog subfamily A member 1 (DNAJA1), were verified to interact with HDAC6. The acetylation levels of these proteins were negatively regulated by HDAC6 both in the mouse liver and in cultured cells. Functional studies reveal that HDAC6-mediated deacetylation modulates the actin-binding ability of MYH9 and the interaction between Hsc70 and DNAJA1. These findings consolidate the notion that HDAC6 serves as a critical regulator of protein acetylation with the capability of coordinating various cellular functions.
Electronic supplementary material
The online version of this article (doi:10.1007/s13238-014-0102-8) contains supplementary material, which is available to authorized users.
doi:10.1007/s13238-014-0102-8
PMCID: PMC4286133  PMID: 25311840
HDAC6; substrate; lysine acetylation; quantitative proteomics; interaction
18.  Epidermal growth factor upregulates serotonin transporter and its association with visceral hypersensitivity in irritable bowel syndrome 
World Journal of Gastroenterology : WJG  2014;20(37):13521-13529.
AIM: To investigate the role of epidermal growth factor (EGF) in visceral hypersensitivity and its effect on the serotonin transporter (SERT).
METHODS: A rat model for visceral hypersensitivity was established by intra-colonic infusion of 0.5% acetic acid in 10-d-old Sprague-Dawley rats. The visceral sensitivity was assessed by observing the abdominal withdrawal reflex and recording electromyographic activity of the external oblique muscle in response to colorectal distension. An enzyme-linked immunosorbent assay was used to measure the EGF levels in plasma and colonic tissues. SERT mRNA expression was detected by real-time PCR while protein level was determined by Western blot. The correlation between EGF and SERT levels in colon tissues was analyzed by Pearson’s correlation analysis. SERT function was examined by tritiated serotonin (5-HT) uptake experiments. Rat intestinal epithelial cells (IEC-6) were used to examine the EGF regulatory effect on SERT expression and function via the EGF receptor (EGFR).
RESULTS: EGF levels were significantly lower in the rats with visceral hypersensitivity as measured in plasma (2.639 ± 0.107 ng/mL vs 4.066 ± 0.573 ng/mL, P < 0.01) and in colonic tissue (3.244 ± 0.135 ng/100 mg vs 3.582 ± 0.197 ng/100 mg colon tissue, P < 0.01) compared with controls. Moreover, the EGF levels were positively correlated with SERT levels (r = 0.820, P < 0.01). EGF displayed dose- and time-dependent increased SERT gene expressions in IEC-6 cells. An EGFR kinase inhibitor inhibited the effect of EGF on SERT gene upregulation. SERT activity was enhanced following treatment with EGF (592.908 ± 31.515 fmol/min per milligram vs 316.789 ± 85.652 fmol/min per milligram protein, P < 0.05) and blocked by the EGFR kinase inhibitor in IEC-6 cells (590.274 ± 25.954 fmol/min per milligram vs 367.834 ± 120.307 fmol/min per milligram protein, P < 0.05).
CONCLUSION: A decrease in EGF levels may contribute to the formation of visceral hypersensitivity through downregulation of SERT-mediated 5-HT uptake into enterocytes.
doi:10.3748/wjg.v20.i37.13521
PMCID: PMC4188903  PMID: 25309082
Epidermal growth factor; Visceral hypersensitivity; Rat models; Serotonin transporter; Rat small intestinal epithelial cells; Intestinal epithelial cells; Irritable bowel syndrome
19.  Modulation of the stability and activities of HIV-1 Tat by its ubiquitination and carboxyl-terminal region 
Cell & Bioscience  2014;4(1):61.
Background
The transactivator of transcription (Tat) protein of human immunodeficiency virus type 1 (HIV-1) is known to undergo ubiquitination. However, the roles of ubiquitination in regulating Tat stability and activities are unclear. In addition, although the 72- and 86-residue forms are commonly used for in vitro studies, the 101-residue form is predominant in the clinical isolates of HIV-1. The influence of the carboxyl-terminal region of Tat on its functions remains unclear.
Results
In this study, we find that Tat undergoes lysine 48-linked ubiquitination and is targeted to proteasome-dependent degradation. Expression of various ubiquitin mutants modulates Tat activities, including the transactivation of transcription, induction of apoptosis, interaction with tubulin, and stabilization of microtubules. Moreover, the 72-, 86- and 101-residue forms of Tat also exhibit different stability and aforementioned activities.
Conclusions
Our findings demonstrate that the ubiquitination and carboxyl-terminal region of Tat are critical determinants of its stability and activities.
doi:10.1186/2045-3701-4-61
PMCID: PMC4201738  PMID: 25328666
Tat; Ubiquitination; Carboxyl-terminal region; Stability; Activity
20.  The Effect of Erythropoietin on Autologous Stem Cell-Mediated Bone Regeneration 
Biomaterials  2013;34(30):7364-7371.
Mesenchymal stem cells (MSCs) although used for bone tissue engineering are limited by the requirement of isolation and culture prior to transplantation. Our recent studies have shown that biomaterial implants can be engineered to facilitate the recruitment of MSCs. In this study, we explore the ability of these implants to direct the recruitment and the differentiation of MSCs in the setting of a bone defect. We initially determined that both stromal derived factor-1alpha (SDF-1α) and erythropoietin (Epo) prompted different degrees of MSC recruitment. Additionally, we found that Epo and bone morphogenetic protein-2 (BMP-2), but not SDF-1α, triggered the osteogenic differentiation of MSCs in vitro. We then investigated the possibility of directing autologous MSC-mediated bone regeneration using a murine calvaria model. Consistent with our in vitro observations, Epo-releasing scaffolds were found to be more potent in bridging the defect than BMP-2 loaded scaffolds, as determined by Computed Tomography (CT) scanning, fluorescent imaging and histological analyses. These results demonstrate the tremendous potential, directing the recruitment and differentiation of autologous MSCs has in the field of tissue regeneration.
doi:10.1016/j.biomaterials.2013.06.031
PMCID: PMC3753364  PMID: 23831188
Autologous stem cells; Scaffold; Erythropoietin; Stromal derived factor-1α; Bone morphogenetic protein-2; Bone; Calvaria; Bone Tissue Engineering
21.  Feeding a High-Concentrate Corn Straw Diet Induced Epigenetic Alterations in the Mammary Tissue of Dairy Cows 
PLoS ONE  2014;9(9):e107659.
Purpose
The objective of this study was to investigate the effects of feeding a high-concentrate corn straw (HCS) diet (65% concentrate+35% corn straw) on the epigenetic changes in the mammary tissue of dairy cows in comparison with a low-concentrate corn straw (LCS) diet (46% concentrate+54% corn straw) and with a low-concentrate mixed forage (LMF) diet (46% concentrate+54% mixed forage).
Experimental Design
Multiparous mid-lactation Chinese Holstein cows were fed one of these three diets for 6 weeks, at which time blood samples and mammary tissue samples were collected. Mammary arterial and venous blood samples were analyzed for lipopolysaccharide (LPS) concentrations while mammary tissue samples were assayed for histone H3 acetylation and the methylation of specific genes associated with fat and protein synthesis.
Results
Extraction of histones and quantification of histone H3 acetylation revealed that acetylation was significantly reduced in cows fed the HCS diet, as compared with cows fed the LCS diet. Cows fed the HCS diet had significantly higher LPS concentrations in the mammary arterial blood, as compared with cows fed the LCS diet. We found that the extent of histone H3 acetylation was negatively correlated with LPS concentrations. The methylation of the stearoyl-coenzyme A desaturase gene associated with milk fat synthesis was increased in cows fed the HCS diet. By contrast, methylation of the gene encoding the signal transducer and activator of transcription 5A was reduced in cows fed the HCS diet, suggesting that feeding a high-concentrate corn straw diet may alter the methylation of specific genes involved in fat and protein synthesis in the mammary tissue of dairy cows.
Conclusions
Feeding the high-concentrate diet induced epigenetic changes in the mammary tissues of dairy cows, possibly through effecting the release of differing amounts of LPS into the mammary blood.
doi:10.1371/journal.pone.0107659
PMCID: PMC4164636  PMID: 25222274
22.  Manifestations of gastrointestinal plasmablastic lymphoma: A case series with literature review 
World Journal of Gastroenterology : WJG  2014;20(33):11894-11903.
Plasmablastic lymphoma (PBL) rarely occurs in the gastrointestinal (GI) tract with limited studies reported. We reviewed the clinical histories and pathology of four patients with GI PBL at our institute and similar case reports published in peer-reviewed journals. In our first case, a 40 year-old human immunodeficiency virus positive male presented with a hemorrhoid-like sensation, and was diagnosed with PBL via biopsy of a rectal mass. The second case involves a 65 year-old healthy male with bloody diarrhea who was found to have PBL in a resected sigmoid mass. The third patient was a 41 year-old male with a history of Crohn’s disease who presented with abdominal pain, diarrhea, and weight loss. A small intestinal mass (PBL) was removed. The fourth patient was a 65-year-old male who was found PBL after surgical resection of bowel for his florid Crohn’s disease. He later developed secondary acute myeloid leukemia. Clinical outcome was very poor in 3 out of 4 patients as reported in the literature. One patient survived chemotherapy followed by autologous transplant. The prototypical clinical presentation and variations of PBL can help create a more comprehensive differential diagnosis for GI tumors and establish an appropriate therapeutic guideline.
doi:10.3748/wjg.v20.i33.11894
PMCID: PMC4155383  PMID: 25206297
Plasmablastic lymphoma; Undifferentiated carcinoma; Non-Hodgkin lymphoma; Diverse clinical manifestation and treatment
23.  Risk factors for hypospadias in China 
Asian Journal of Andrology  2014;16(5):778-781.
This case-controlled study was designed to evaluate the association between various baseline parental factors and the risk of hypospadias in China. Patients were selected from tertiary referral hospitals in Anhui, a province in mid-eastern China. A questionnaire was given to the parents of each patient. The final database included 193 cases and 835 controls. The incidence of additional coexistent anomalies was 13.0%, primarily cryptorchidism (9.8%). Ten patients (5.1%) were from families with genital anomaly, including five families (2.6%) with hypospadias. The risks of hypospadias was higher for children of mothers > 35 (odds ratio [OR] =1.47) and < 18 (OR = 2.95) years of age, and in mothers who had consumed alcohol (OR = 2.67), used drugs (OR = 1.53) and had an infection (OR = 1.87) during pregnancy. The risk of hypospadias was also higher when mothers (OR = 1.68) and fathers (OR = 1.74) were engaged in agriculture. Other factors assessed were not associated with the risk of hypospadias.
doi:10.4103/1008-682X.131704
PMCID: PMC4215668  PMID: 24875823
genetics; hypospadias; maternal exposures; paternal exposures; pregnancy; risk factors
24.  The DNA Binding Property of PML/RARA but Not the Integrity of PML Nuclear Bodies Is Indispensable for Leukemic Transformation 
PLoS ONE  2014;9(8):e104906.
PML/RARA is the oncoprotein driving acute promyelocytic leukemia (APL). It suppresses genes expression by recruitment of a number of transcriptional repressors, resulting in differentiation block and malignant transformation of hematopoietic cells. Here, we found that mice primary hematopoietic progenitor cells (HPCs), transduced by DNA-binding-defective PML/RARA mutants, were deficient in colony formation. Further experiments showed that DNA-binding-defective PML/RARA mutants could not repress the transcription of retinoic acid regulated genes. Intriguingly, there were no significant differences of the micro-speckled intracellular distribution between the mutants and wild-type PML/RARA. Some retinoic acid target genes regulated by PML/RARA are involved in not only differentiation block but also hematopoietic cell self-renewal. Altogether, our data demonstrate that direct DNA-binding is essential for PML/RARA to immortalize hematopoietic cells, while disruption of PML-nuclear body does not seem to be a prerequisite for hematopoietic cell transformation.
doi:10.1371/journal.pone.0104906
PMCID: PMC4131979  PMID: 25119106
25.  Feeding a high-concentrate corn straw diet increased the release of endotoxin in the rumen and pro-inflammatory cytokines in the mammary gland of dairy cows 
BMC Veterinary Research  2014;10:172.
Background
The objective of this study was to investigate the effects of feeding a high-concentrate corn straw diet on the release of endotoxin in the rumen and the changes of pro-inflammatory cytokines in the mammary gland of dairy cows in comparison with a low-concentrate corn straw diet and a low-concentrate mixed forage diet. Thirty second-parity Chinese Holstein cows in mid-lactation with a body condition score of 2.86 ± 0.29, weighing 543 ± 57 kg and producing 24.32 ± 3.86 kg milk per day were randomly assigned to 1 of the 3 diets (n = 10 per treatment): 1) low-concentrate mixed forage diet (LCF) with a concentrate to roughage ratio of 46 : 54; 2) high-concentrate corn straw diet (HCS) with a concentrate to roughage ratio of 65 : 35; 3) low-concentrate corn straw diet (LCS) with the same concentrate to roughage ratio (46 : 54) as LCF. The experiment lasted 6 weeks, and samples were collected in the last week. Milk samples were analyzed for conventional components, rumen fluid samples were analyzed for pH and endotoxin, and mammary arterial and venous plasma samples were analyzed for concentrations of interleukin (IL)-1β, IL-6, IL-8 and tumor necrosis factor alpha (TNF-α).
Results
Concentrations of endotoxin in rumen fluid and feces of cows fed HCS were significantly higher than those of cows fed LCS and LCF. Feeding HCS increased the release of IL-1β, IL-6 and IL-8 in the mammary gland compared with feeding LCS. Concentrations of cytokines (IL-1β and IL-8) in mammary venous plasma had a negative correlation with milk production efficiencies.
Conclusions
Results indicated that the high-concentrate corn straw diet increased the concentrations of endotoxin in rumen fluid and feces. Furthermore, feeding the high-concentrate corn straw diet stimulated the mammary gland to release more pro-inflammatory cytokines. The results suggest that feeding a high-concentrate corn straw diet induce a higher pro-inflammatory response in the mammary gland and thus may partly decrease the milk production efficiencies in dairy cows.
doi:10.1186/s12917-014-0172-0
PMCID: PMC4236824  PMID: 25084830
Cytokine; Dairy cow; Endotoxin; Mammary gland

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