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1.  Tolerance to High Temperature Extremes in an Invasive Lace Bug, Corythucha ciliata (Hemiptera: Tingidae), in Subtropical China 
PLoS ONE  2013;8(1):e54372.
Biological invasions are predicted to be more frequent as climate change is increasing its positive impact on the prevalence of invasive exotic species. Success of insect invaders in different temperature zones is closely related to their tolerance to temperature extremes. In this study, we used an exotic lace bug (Corythucha ciliata) as the study organism to address the hypotheses that an insect species invading a subtropical zone from temperate regions has a high capacity to survive and adapt to high temperatures, and that its thermal tolerance plays an important role in determining its seasonal abundance and geographic distribution. To test these hypotheses, the effects of heat shock on the survival and reproduction of C. ciliata adults were assessed in the laboratory. Adults were exposed to 26 (control), 35, 37, 39, 41, 43, and 45°C for 2 h, and then were transferred to 26°C. Heat-shock temperatures ranging from 35 to 41°C did not significantly affect survival pattern, longevity, and fecundity of adults, but heat shock at 43 and 45°C significantly reduced these traits. Exposing parent females to heat-shock treatments from 35 to 41°C did not significantly affect the hatching rate of their eggs, survival of the nymphs, and the proportion of female F1 progeny, while no progeny were produced with treatments of 43 and 45°C. The results indicate that C. ciliata can tolerate high temperatures less than 41°C, which may contribute to its expansion into the lower latitudes in China where its hosts (Platanus trees) are widely planted. Our findings have important implications for predicting seasonal abundance and understanding invasion mechanisms of this important urban invader under climate change.
doi:10.1371/journal.pone.0054372
PMCID: PMC3554765  PMID: 23365664
2.  Mucin Deficiency Causes Functional and Structural Changes of the Ocular Surface 
PLoS ONE  2012;7(12):e50704.
MUC5AC is the most abundant gel-forming mucin in the ocular system. However, the specific function is unknown. In the present study, a Muc5ac knockout (KO) mouse model was subject to various physiological measurements as compared to its wide-type (WT) control. Interestingly, when KO mice were compared to WT mice, the mean tear break up time (TBUT) values were significantly lower and corneal fluorescein staining scores were significantly higher. But the tear volume was not changed. Despite the lack of Muc5ac expression in the conjunctiva of KO mice, Muc5b expression was significantly increased in these mice. Corneal opacification, varying in location and severity, was found in a few KO mice but not in WT mice. The present results suggest a significant difference in the quality, but not the quantity, of tear fluid in the KO mice compared to WT mice. Dry eye disease is multifactorial and therefore further evaluation of the varying components of the tear film, lacrimal unit and corneal structure of these KO mice may help elucidate the role of mucins in dry eye disease. Because Muc5ac knockout mice have clinical features of dry eye, this mouse model will be extremely useful for further studies regarding the pathophysiology of the ocular surface in dry eye in humans.
doi:10.1371/journal.pone.0050704
PMCID: PMC3525643  PMID: 23272068
3.  Magnetic Catechol-Chitosan with Bioinspired Adhesive Surface: Preparation and Immobilization of ω-Transaminase 
PLoS ONE  2012;7(7):e41101.
The magnetic chitosan nanocomposites have been studied intensively and been used practically in various biomedical and biological applications including enzyme immobilization. However, the loading capacity and the remained activity of immobilized enzyme based on existing approaches are not satisfied. Simpler and more effective immobilization strategies are needed. Here we report a simple catechol modified protocol for preparing a novel catechol-chitosan (CCS) - iron oxide nanoparticles (IONPs) composites carrying adhesive moieties with strong surface affinity. The ω-transaminase (ω-TA) was immobilized onto this magnetic composite via nucleophilic reactions between catechol and ω-TA. Under optimal conditions, 87.5% of the available ω-TA was immobilized on the composite, yielding an enzyme loading capacity as high as 681.7 mg/g. Furthermore, the valuation of enzyme activity showed that ω-TA immobilized on CCS-IONPs displayed enhanced pH and thermal stability compared to free enzyme. Importantly, the immobilized ω-TA retained more than 50% of its initial activity after 15 repeated reaction cycles using magnetic separation and 61.5% of its initial activity after storage at 4°C in phosphate buffered saline (PBS) for 15 days. The results suggested that such adhesive magnetic composites may provide an improved platform technology for bio-macromolecules immobilized.
doi:10.1371/journal.pone.0041101
PMCID: PMC3398885  PMID: 22815930
4.  ZIP8 expression in human proximal tubule cells, human urothelial cells transformed by Cd+2 and As+3 and in specimens of normal human urothelium and urothelial cancer 
Background
ZIP8 functions endogenously as a Zn+2/HCO3- symporter that can also bring cadmium (Cd+2) into the cell. It has also been proposed that ZIP8 participates in Cd-induced testicular necrosis and renal disease. In this study real-time PCR, western analysis, immunostaining and fluorescent localization were used to define the expression of ZIP8 in human kidney, cultured human proximal tubule (HPT) cells, normal and malignant human urothelium and Cd+2 and arsenite (As+3) transformed urothelial cells.
Results
It was shown that in the renal system both the non-glycosylated and glycosylated form of ZIP8 was expressed in the proximal tubule cells with localization of ZIP8 to the cytoplasm and cell membrane; findings in line with previous studies on ZIP8. The studies in the bladder were the first to show that ZIP8 was expressed in normal urothelium and that ZIP8 could be localized to the paranuclear region. Studies in the UROtsa cell line confirmed a paranuclear localization of ZIP8, however addition of growth medium to the cells increased the expression of the protein in the UROtsa cells. In archival human samples of the normal urothelium, the expression of ZIP8 was variable in intensity whereas in urothelial cancers ZIP8 was expressed in 13 of 14 samples, with one high grade invasive urothelial cancer showing no expression. The expression of ZIP8 was similar in the Cd+2 and As+3 transformed UROtsa cell lines and their tumor transplants.
Conclusion
This is the first study which shows that ZIP8 is expressed in the normal urothelium and in bladder cancer. In addition the normal UROtsa cell line and its transformed counterparts show similar expression of ZIP8 compared to the normal urothelium and the urothelial cancers suggesting that the UROtsa cell line could serve as a model system to study the expression of ZIP8 in bladder disease.
doi:10.1186/1475-2867-12-16
PMCID: PMC3390278  PMID: 22550998
Zinc transport; Cadmium transport; ZIP8; Proximal tubule; Renal toxicity; Urothelium; Urothelial cancer; Arsenic
5.  Integrated approaches reveal determinants of genome-wide binding and function of the transcription factor Pho4 
Molecular cell  2011;42(6):826-836.
SUMMARY
Binding of transcription factors to DNA is a key regulatory step in the control of gene expression. DNA sequences with high affinity for transcription factors occur more frequently in the genome than instances of genes bound or regulated by these factors. Although several mechanisms have been identified that influence the specificity of transcriptional regulation, it is not known if these can explain the observed genome-wide pattern of binding or regulation for a given transcription factor. We used genome-wide approaches to study how trans influences shape the binding and regulatory landscape of Pho4, a budding yeast transcription factor that activates gene expression in response to phosphate limitation. We find that nucleosomes significantly restrict the sites to which Pho4 binds. At nucleosome-depleted sites, competition between Pho4 and another transcription factor, Cbf1, determines Pho4 occupancy, raising the threshold for transcriptional activation by Pho4 in phosphate replete conditions and preventing Pho4 activation of genes outside the phosphate regulon during phosphate starvation. Pho4 binding is not sufficient for transcriptional activation – a cooperative interaction between the transcription factor Pho2 and Pho4 occurs specifically at genes that are activated. Combining these experimental observations, we are able to globally predict Pho4 binding and its functionality. Our study provides insights into the mechanisms of global control by sequence-specific transcription factors.
doi:10.1016/j.molcel.2011.05.025
PMCID: PMC3127084  PMID: 21700227
6.  Kindlin-2 Expression in Arsenite and Cadmium Transformed Bladder Cancer Cell Lines and in Archival Specimens of Human Bladder Cancer 
Urology  2011;77(6):1507.e1-1507.e7.
Objective
The goal of this study was to confirm a microarray study that suggested that Kindlin-2 might play a role in the development and progression of bladder cancer. There has been no previous examination of Kindlin-2 expression in human bladder cancer.
Methods
A combination of real time PCR, western analysis and immunohistochemistry was used to characterize Kindlin-2 expression in arsenite (As+3) and cadmium (Cd+2) transformed human cell lines, their tumor transplants in immune-compromised mice, and in archival specimens of human bladder and bladder cancer.
Results
The results show that the Kindlin-2 expression patterns in the cell lines were not duplicated in the tumor tissues. However, it was shown that Kindlin-2 was expressed in the stromal element of all the transplanted tumors and archival specimens of human bladder cancer. It was also shown that a small number of high grade invasive urothelial cancers have focal expression of Kindlin-2 in the tumor cells.
Conclusion
Kindlin-2 is expressed in the stromal component of most, if not all, human bladder cancers. Kindlin-2 is not expressed in normal urothelium. Kindlin-2 is expressed in a small subset of high grade invasive bladder cancers and may have potential as a prognostic marker for tumor progression.
doi:10.1016/j.urology.2011.02.040
PMCID: PMC3105253  PMID: 21624607
Urothelial Cancer; Kindlin-2; Stroma; Bladder; Urothelium; Biomarker
7.  Pyrosequencing the Bemisia tabaci Transcriptome Reveals a Highly Diverse Bacterial Community and a Robust System for Insecticide Resistance 
PLoS ONE  2012;7(4):e35181.
Background
Bemisia tabaci (Gennadius) is a phloem-feeding insect poised to become one of the major insect pests in open field and greenhouse production systems throughout the world. The high level of resistance to insecticides is a main factor that hinders continued use of insecticides for suppression of B. tabaci. Despite its prevalence, little is known about B. tabaci at the genome level. To fill this gap, an invasive B. tabaci B biotype was subjected to pyrosequencing-based transcriptome analysis to identify genes and gene networks putatively involved in various physiological and toxicological processes.
Methodology and Principal Findings
Using Roche 454 pyrosequencing, 857,205 reads containing approximately 340 megabases were obtained from the B. tabaci transcriptome. De novo assembly generated 178,669 unigenes including 30,980 from insects, 17,881 from bacteria, and 129,808 from the nohit. A total of 50,835 (28.45%) unigenes showed similarity to the non-redundant database in GenBank with a cut-off E-value of 10–5. Among them, 40,611 unigenes were assigned to one or more GO terms and 6,917 unigenes were assigned to 288 known pathways. De novo metatranscriptome analysis revealed highly diverse bacterial symbionts in B. tabaci, and demonstrated the host-symbiont cooperation in amino acid production. In-depth transcriptome analysis indentified putative molecular markers, and genes potentially involved in insecticide resistance and nutrient digestion. The utility of this transcriptome was validated by a thiamethoxam resistance study, in which annotated cytochrome P450 genes were significantly overexpressed in the resistant B. tabaci in comparison to its susceptible counterparts.
Conclusions
This transcriptome/metatranscriptome analysis sheds light on the molecular understanding of symbiosis and insecticide resistance in an agriculturally important phloem-feeding insect pest, and lays the foundation for future functional genomics research of the B. tabaci complex. Moreover, current pyrosequencing effort greatly enriched the existing whitefly EST database, and makes RNAseq a viable option for future genomic analysis.
doi:10.1371/journal.pone.0035181
PMCID: PMC3340392  PMID: 22558125
8.  Gene Expression Profiling in the Thiamethoxam Resistant and Susceptible B-biotype Sweetpotato Whitefly, Bemisia tabaci  
Thiamethoxam has been used as a major insecticide to control the B-biotype sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). Due to its excessive use, a high level of resistance to thiamethoxam has developed worldwide over the past several years. To better understand the molecular mechanisms underlying this resistance in B. tabaci, gene profiles between the thiamethoxam-resistant and thiamethoxam-susceptible strains were investigated using the suppression subtractive hybridization (SSH) library approach. A total of 72 and 52 upand down-regulated genes were obtained from the forward and reverse SSH libraries, respectively. These expressed sequence tags (ESTs) belong to several functional categories based on their gene ontology annotation. Some categories such as cell communication, response to abiotic stimulus, lipid particle, and nuclear envelope were identified only in the forward library of thiamethoxam-resistant strains. In contrast, categories such as behavior, cell proliferation, nutrient reservoir activity, sequence-specific DNA binding transcription factor activity, and signal transducer activity were identified solely in the reverse library.
To study the validity of the SSH method, 16 differentially expressed genes from both forward and reverse SSH libraries were selected randomly for further analyses using quantitative realtime PCR (qRT-PCR). The qRT-PCR results were fairly consistent with the SSH results; however, only 50% of the genes showed significantly different expression profiles between the thiamethoxam-resistant and thiamethoxam-susceptible whiteflies. Among these genes, a putative NAD-dependent methanol dehydrogenase was substantially over-expressed in the thiamethoxamresistant adults compared to their susceptible counterparts. The distributed profiles show that it was highly expressed during the egg stage, and was most abundant in the abdomen of adult females.
doi:10.1673/031.012.4601
PMCID: PMC3476951  PMID: 22957505
insecticide resistance; quantitative real-time PCR; NAD-dependent methanol dehydrogenase; sap-sucking insect; suppression subtractive hybridization
9.  Alcohol ablation at the posterior papillary muscle prevents ventricular fibrillation in swine without affecting mitral valve function 
Europace  2010;12(12):1781-1786.
Aims
Radiofrequency ablation at the posterior papillary muscle (PM) significantly reduced ventricular fibrillation (VF) inducibility in rabbits and dogs, suggesting that PM may be involved in the generation of VF. However, the effect of ablation at the PM on VF inducibility remains unknown in normal intact swine hearts because in this species radiofrequency energy delivered at PM provoked incessant VF.
Methods and results
Twelve anesthetized swine underwent median sternotomy. Under the ultrasonographic guidance, chemical ablation was performed via injection of dehydrated alcohol into the base of the posterior PM (group PM, n = 6) or anterior wall (control group, n = 6) in the left ventricle. Ventricular fibrillation inducibility and mitral valve function were measured pre- and post-ablation. Hearts were explanted and the ablated myocardium was stained with haematoxylin and eosin. Ventricular fibrillation inducibility was significantly decreased from 100 ± 0% pre-ablation to 11.9 ± 7.8% post-ablation in group PM (P = 0.001), whereas it was not statistically different in the control group (100 ± 0 vs. 92.9 ± 7.1%, pre-ablation vs. post-ablation). Haemorrhage and cellular necrosis was observed in the centre of ablated myocardium and no significant mitral regurgitation was observed following ablation at the posterior PM.
Conclusion
Alcohol ablation of the left posterior PM reduced VF inducibility in normal intact swine hearts, with no significant mitral regurgitation. This suggests that the posterior PM may be involved in the generation of VF, and the recurrence of VF may be prevented by chemical ablation at the posterior PM.
doi:10.1093/europace/euq337
PMCID: PMC2988624  PMID: 20858694
Chemical ablation; Ventricular fibrillation; Posterior papillary muscle; Swine
10.  SPARC Gene Expression is Repressed in Human Urothelial Cells (UROtsa) Exposed to or Malignantly Transformed by Cadmium or Arsenite 
Toxicology letters  2010;199(2):166-172.
SPARC belongs to a class of extracellular matrix-associated proteins that have counteradhesive properties. The ability of SPARC to modulate cell-cell and cell-matrix interactions provides a strong rationale for studies designed to determine its expression in cancer. The objective of this study was to determine if SPARC expression was altered in cadmium (Cd+2) and arsenite (As+3) induced bladder cancer and if these alterations were present in archival specimens of human bladder cancer. The expression of SPARC was determined in human parental UROtsa cells, their Cd+2 and As+3 transformed counterparts and derived tumors, and in archival specimens of human bladder cancer using a combination of real time reverse transcriptase polymerase chain reaction, western blotting, immunofluoresence localization and immunohistochemical staining. It was demonstrated that SPARC expression was down-regulated in Cd+2 and As+3 transformed UROtsa cells. In addition, the malignant epithelial component of tumors derived from these cell lines were also down-regulated for SPARC expression, but the stromal cells recruited to these tumors was highly reactive for SPARC. This finding was shown to translate to specimens of human bladder cancer where tumor cells were SPARC negative, but stromal cells were positive. Acute exposure of UROtsa cells to both cadmium and arsenite reduced the expression of SPARC through a mechanism that did not involve changes in DNA methylation or histone acetylation. These studies suggest that environmental exposure to As+3 or Cd+2 can alter cell-cell and cell-matrix interactions in normal urothelial cells through a reduction in the expression of SPARC. The SPARC associated loss of cell-cell and cell-matrix contacts may participate in the multi-step process of bladder carcinogenesis.
doi:10.1016/j.toxlet.2010.08.020
PMCID: PMC2956785  PMID: 20837119
Arsenite; cadmium; SPARC; and bladder cancer
11.  Arsenic, cadmium and neuron specific enolase (ENO2, γ-enolase) expression in breast cancer 
Background
Neuron specific enolase (ENO2, γ-enolase) has been used as a biomarker to help identify neuroendocrine differentiation in breast cancer. The goal of the present study was to determine if ENO2 expression in the breast epithelial cell is influenced by the environmental pollutants, arsenite and cadmium. Acute and chronic exposure of MCF-10A cells to As+3 and Cd+2 sufficient to allow colony formation in soft agar, was used to determine if ENO2 expression was altered by these pollutants.
Results
It was shown that both As+3 and Cd+2 exposure caused significant increases in ENO2 expression under conditions of both acute and chronic exposure. In contrast, ENO1, the major glycolytic enolase in non-muscle and neuronal cells, was largely unaffected by exposure to either As+3 or Cd+2. Localization studies showed that ENO2 in the MCF-10A cells transformed by As+3 or Cd+2 had both a cytoplasmic and nuclear localization. In contrast, ENO1 was localized to the cytoplasm. ENO2 localized to the cytoplasm was found to co-localized with ENO1.
Conclusion
The results are the first to show that ENO2 expression in breast epithelial cells is induced by acute and chronic exposure to As+3 or Cd+2. The findings also suggest a possible link between As+3 and Cd+2 exposure and neuroendocrine differentiation in tumors. Overall, the results suggest that ENO2 might be developed as a biomarker indicating acute and/or chronic environmental exposure of the breast epithelial cell to As+3 and Cd+2.
doi:10.1186/1475-2867-11-41
PMCID: PMC3233504  PMID: 22098917
Biomarker; arsenic; cadmium; breast cancer; breast epithelial cells; MCF-10A; enolase; ENO; neuron specific enolase; ENO2
12.  Absence of Metallothionein 3 Expression in Breast Cancer is a Rare, But Favorable Marker of Outcome that is Under Epigenetic Control 
Cadmium (Cd+2), a known carcinogen mimics the effects of estrogen in the uterus and mammary gland suggesting its possible involvement in the development and progression of breast cancer. This lab showed through analysis of a small set of archival human diagnostic specimens that the third isoform of the classic Cd+2 binding protein metallothionein (MT-3), is not expressed in normal breast tissue, but is expressed in some breast cancers and that expression tends to correlate with a poor disease outcome. The goals of the present study were to verify that overexpression of MT-3 in a large set of archival human diagnostic specimens tends to correlate with poor disease outcome and define the mechanism of MT-3 gene regulation in the normal breast epithelial cell. The results showed that MT-3 was expressed in approximately 90% of all breast cancers and was absent in normal breast epithelium. The lack of MT-3 staining in some cancers correlated with a favorable patient outcome. High frequency of MT-3 staining was also found for in situ breast cancer suggesting that MT-3 might be an early biomarker for breast cancer. The study also demonstrated that the MCF-10A cell line, an immortalized, non-tumorigenic model of human breast epithelial cells, displayed no basal expression of MT-3, nor was it induced by Cd+2. Treatment of the MCF-10A cells with the demethylation agent, 5-Aza-2′-deoxycytidine, or the histone deacetylase inhibitor, MS-275, restored MT-3 mRNA expression. It was also shown that the MT-3 metal regulatory elements are potentially active binders of protein factors following treatment with these inhibitors suggesting that MT-3 expression may be subject to epigenetic regulation.
doi:10.1080/02772241003711274
PMCID: PMC3002175  PMID: 21170156
13.  Keratin 6 Expression Correlates to Areas of Squamous Differentiation in Multiple Independent Isolates of As+3-Induced Bladder Cancer 
This laboratory has shown that arsenite (As+3) exposure can cause the malignant transformation of the UROtsa human urothelial cell line. This single isolate formed subcutaneous tumors with a histology similar to human urothelial cell carcinoma. The tumors also displayed areas of squamous differentiation of the urothelial cells, an infrequent, but known component of human bladder cancer. In the present study, five additional independent isolates of As+3 -transformed urothelial cells were isolated and each were shown to produce subcutaneous urothelial cell tumors with a characteristic histology very similar to those described in the initial report. That there were underlying phenotypic differences in the 6 independent isolates was demonstrated when they were assessed for their ability to form tumors within the peritoneal cavity. It was shown that two isolates could form hundreds of small peritoneal tumor nodules, one isolate a moderate number of tumor nodules, and three isolates no or only one tumor nodule. The peritoneal tumors were also characterized for their degree of squamous differentiation of the urothelial cells and, while areas of squamous differentiation could be found, such differentiation was substantially reduced compared to subcutaneous tumors. Immunostaining for keratin 6 was tested as a potential marker for malignant urothelial cells that had undergone squamous differentiation. Keratin 6 was shown to consistently stain only cells having some evidence of squamous differentiation. Keratin 16 was shown to follow the staining pattern of keratin 6. The isolates and tumor heterotransplants were all examined for keratin 6, 16 and 17 mRNA and protein expression.
doi:10.1002/jat.1513
PMCID: PMC3100548  PMID: 20186695
Urothelial Cell Carcinoma; Squamous Differentiation; Bladder; Arsenite; Keratin 6; Keratin 16; Keratin 17
14.  Beclin-1 Expression in Normal Bladder and in Cd+2 and As+3 Exposed and Transformed Human Urothelial Cells (UROtsa) 
Toxicology letters  2010;195(1):15-22.
The expression of beclin-1 in normal human bladder and in Cd+2 and As+3 exposed and transformed urothelial cells (UROtsa) was examined in this study. It was shown using a combination of real time PCR, western analysis and immunohistochemistry that beclin-1 was expressed in the urothelial cells of the normal bladder. It was also demonstrated that the parental UROtsa cell line expressed beclin-1 mRNA and protein at levels similar to that of the in situ urothelium. The level of beclin-1 expression underwent only modest alterations when the UROtsa cells were malignantly transformed by Cd+2 or As+3 or when the parental cells were exposed acutely to Cd+2 or As+3. While there were instances of significant alterations at individual time points and within cell line-to-cell line comparisons there was no evidence of a dose response relationship or correlations to the phenotypic properties of the cell lines. Similar results were obtained for the expression of the Atg-5, Atg-7, Atg-12 and LC3B autophagy-related proteins. The findings provide initial evidence for beclin-1 expression in normal bladder and that large alterations in the expression of beclin-1 and associated proteins do not occur when human urothelial cells are malignantly transformed with, or exposed to, either Cd+2 or As+3.
doi:10.1016/j.toxlet.2010.02.021
PMCID: PMC2856728  PMID: 20206246
Arsenite; cadmium; bladder; beclin-1; and autophagy
15.  The association of HLA-DQB1, -DQA1 and -DPB1 alleles with anti- glomerular basement membrane (GBM) disease in Chinese patients 
BMC Nephrology  2011;12:21.
Background
Human leukocyte antigen (HLA) alleles are associated with many autoimmune diseases, including anti-glomerular basement membrane (GBM) disease. In our previous study, it was demonstrated that HLA-DRB1*1501 was strongly associated with anti-GBM disease in Chinese. However, the association of anti-GBM disease and other HLA class II genes, including HLA-DQB1, -DQA1,-DPB1 alleles, has rarely been investigated in Asian, especially Chinese patients. The present study further analyzed the association between anti-GBM disease and HLA-DQB1, -DQA1, and -DPB1 genes. Apart from this, we tried to locate the potential risk amino acid residues of anti-GBM disease.
Methods
This study included 44 Chinese patients with anti-GBM disease and 200 healthy controls. The clinical and pathological data of the patients were collected and analyzed. Typing of HLA-DQB1, -DQA1 and -DPB1 alleles were performed by bi-directional sequencing of exon 2 using the SeCoreTM Sequencing Kits.
Results
Compared with normal controls, the prevalence of HLA-DPB1*0401 was significantly lower in patients with anti-GBM disease (3/88 vs. 74/400, p = 4.4 × 10-4, pc = 0.039). Comparing with normal controls, the combination of presence of DRB1*1501 and absence of DPB1*0401 was significantly prominent among anti-GBM patients (p = 2.0 × 10-12, pc = 1.7 × 10-10).
Conclusions
HLA-DPB1*0401 might be a protective allele to anti-GBM disease in Chinese patients. The combined presence of DRB1*1501 and absence of DPB1*0401 might have an even higher risk to anti-GBM disease than HLA-DRB1*1501 alone.
doi:10.1186/1471-2369-12-21
PMCID: PMC3107170  PMID: 21569485
Anti-GBM disease; HLA-DPB1*0401; Chinese
16.  Metastasis-associated protein 1 induces VEGF-C and facilitates lymphangiogenesis in colorectal cancer 
AIM: To study the correlation between high metastasis-associated protein 1 (MTA1) expression and lymphangiogenesis in colorectal cancer (CRC) and its role in production of vascular endothelial growth factor-C(VEGF-C).
METHODS: Impact of high MTA1 and VEGF-C expression levels on disease progression and lymphovascular density (LVD, D2-40-immunolabeled) in 81 cases of human CRC was evaluated by immunohistochemistry. VEGF-C mRNA and protein expressions in human LoVo and HCT116 cell lines were detected by real-time polymerase chain reaction and Western blotting, respectively, with a stable expression vector or siRNA.
RESULTS: The elevated MTA1 and VEGF-C expression levels were correlated with lymph node metastasis and Dukes stages (P < 0.05). Additionally, high MTA1 expression level was correlated with a large tumor size (P < 0.05). A significant correlation was found between MTA1 and VEGF-C protein expressions in tumor cells (r = 0.371, P < 0.05). Similar to the VEGF-C expression level, high MTA1 expression level was correlated with high LVD in CRC (P < 0.05). Furthermore, over-expression of MTA1 significantly enhanced the VEGF-C mRNA and protein expression levels, whereas siRNAs - knocked down MTA1 decreased the VEGF-C expression level.
CONCLUSION: MTA1, as a regulator of tumor-associated lymphangiogenesis, promotes lymphangiogenesis in CRC by mediating the VEGF-C expression.
doi:10.3748/wjg.v17.i9.1219
PMCID: PMC3063917  PMID: 21448429
Metastasis-associated protein 1; Vascular endothelial growth factor-C; Lymphangiogenesis; Colorectal cancer
17.  Variation of Keratin 7 Expression and Other Phenotypic Characteristics of Independent Isolates of Cadmium Transformed Human Urothelial Cells (UROtsa) 
This laboratory has shown that a human urothelial cell line (UROtsa) transformed by cadmium (Cd+2) produced subcutaneous tumor heterotransplants that resemble human transitional cell carcinoma (TCC). In the present study, additional Cd+2 transformed cell lines were isolated to determine if independent exposures of the cell line to Cd+2 would result in malignantly transformed cell lines possessing similar phenotypic properties. Seven independent isolates were isolated and assessed for their doubling times, morphology, ability to heterotransplant subcutaneously and in the peritoneal cavity of nude mice and for the expression keratin 7. The 7 cell lines all displayed an epithelial morphology with no evidence of squamous differentiation. Doubling times were variable among the isolates, being significantly reduced or similar to the parental cells. All 7 isolates were able to form subcutaneous tumor heterotransplants with a TCC morphology and all heterotransplants displayed areas of squamous differentiation of the transitional cells. The degree of squamous differentiation varied among the isolates. In contrast to subcutaneous tumor formation, only 1 isolate of the Cd+2 transformed cells (UTCd#1) was able to effectively colonize multiple sites within the peritoneal cavity. An analysis of keratin 7 expression showed no correlation with squamous differentiation for the subcutaneous heterotransplants generated from the 7 cell lines. Keratin 7 was expressed in 6 of the 7 cell lines and their subcutaneous tumor heterotransplants. Keratin 7 was not expressed in the cell line that was able to form tumors within the peritoneal cavity. These results show that individual isolates of Cd+2 transformed cells have both similarities and differences in their phenotype.
doi:10.1021/tx900346q
PMCID: PMC2822111  PMID: 19921857
18.  Identification of a natural human serotype 3 parainfluenza virus 
Virology Journal  2011;8:58.
Parainfluenza virus is an important pathogen threatening the health of animals and human, which brings human many kinds of disease, especially lower respiratory tract infection involving infants and young children. In order to control the virus, it is necessary to fully understand the molecular basis resulting in the genetic diversity of the virus. Homologous recombination is one of mechanisms for the rapid change of genetic diversity. However, as a negative-strand virus, it is unknown whether the recombination can naturally take place in human PIV. In this study, we isolated and identified a mosaic serotype 3 human PIV (HPIV3) from in China, and also provided several putative PIV mosaics from previous reports to reveal that the recombination can naturally occur in the virus. In addition, two swine PIV3 isolates transferred from cattle to pigs were found to have mosaic genomes. These results suggest that homologous recombination can promote the genetic diversity and potentially bring some novel biologic characteristics of HPIV.
doi:10.1186/1743-422X-8-58
PMCID: PMC3045893  PMID: 21306605
19.  Differences in the epigenetic regulation of MT-3 gene expression between parental and Cd+2 or As+3 transformed human urothelial cells 
Background
Studies have shown that metallothionein 3 (MT-3) is not expressed in normal urothelium or in the UROtsa cell line, but is expressed in urothelial cancer and in tumors generated from the UROtsa cells that have been transformed by cadmium (Cd+2) or arsenite (As+3).The present study had two major goals. One, to determine if epigenetic modifications control urothelial MT-3 gene expression and if regulation is altered by malignant transformation by Cd+2 or As+3. Two, to determine if MT-3 expression might translate clinically as a biomarker for malignant urothelial cells released into the urine.
Results
The histone deacetylase inhibitor MS-275 induced MT-3 mRNA expression in both parental UROtsa cells and their transformed counterparts. The demethylating agent, 5-Aza-2'-deoxycytidine (5-AZC) had no effect on MT-3 mRNA expression. ChIP analysis showed that metal-responsive transformation factor-1 (MTF-1) binding to metal response elements (MRE) elements of the MT-3 promoter was restricted in parental UROtsa cells, but MTF-1 binding to the MREs was unrestricted in the transformed cell lines. Histone modifications at acetyl H4, trimethyl H3K4, trimethyl H3K27, and trimethyl H3K9 were compared between the parental and transformed cell lines in the presence and absence of MS-275. The pattern of histone modifications suggested that the MT-3 promoter in the Cd+2 and As+3 transformed cells has gained bivalent chromatin structure, having elements of being "transcriptionally repressed" and "transcription ready", when compared to parental cells. An analysis of MT-3 staining in urinary cytologies showed that a subset of both active and non-active patients with urothelial cancer shed positive cells in their urine, but that control patients only rarely shed MT-3 positive cells.
Conclusion
The MT-3 gene is silenced in non-transformed urothelial cells by a mechanism involving histone modification of the MT-3 promoter. In contrast, transformation of the urothelial cells with either Cd+2 or As+3 modified the chromatin of the MT-3 promoter to a bivalent state of promoter readiness. Urinary cytology for MT-3 positive cells would not improve the diagnosis of urothelial cancer, but might have potential as a biomarker for tumor progression.
doi:10.1186/1475-2867-11-2
PMCID: PMC3041731  PMID: 21303554
20.  Retrospective analysis of anterior correction and fusion for adolescent idiopathic thoracolumbar/lumbar scoliosis: the relationship between preserving mobile segments and trunk balance 
International Orthopaedics  2008;33(1):191-196.
The objective of this paper was to investigate the surgical strategy of the selection of the lowest instrumented vertebrae (LIV) in anterior correction for adolescent idiopathic scoliosis (AIS) and to discuss the relationship between the LIV and trunk balance. From 1998 to 2004, 28 patients with thoracolumbar/lumbar AIS (Lenke 5 type) were treated by anterior correction and fusion with a mean follow-up of 1.5 years. Specific radiographic parameters were observed respectively and the correlation between disc wedging immediately below the LIV and these parameters was analysed. The mean corrective rate of major curves was 74.84%. The preoperative disc angle distal to LIV was 2.96 ± 1.43° and postoperatively it was −3.60 ± 1.75°. The postoperative disc wedging was most correlated with LIV obliquity. The postoperative LIV–CSVL (centre sacral vertical line) distance, which reflects regional balance, was correlated with various preoperative parameters. LIV determination was correlated with multiple preoperative radiographic parameters. Disc wedging distal to LIV occurs most often when a short fusion excluding the lower end vertebra (LEV) and the subjacent disc are nearly parallel.
doi:10.1007/s00264-007-0489-4
PMCID: PMC2899232  PMID: 18188567
21.  Transformation of Human Urothelial Cells (UROtsa) by As3+ and Cd2+ Induces the Expression of Keratin 6a 
Environmental Health Perspectives  2007;116(4):434-440.
Background
Cadmium and arsenite can directly and malignantly transform the UROtsa cell line. The tumor heterotransplants produced from these transformed cells have histologic features consistent with human bladder cancer. Previous microarray analysis of total RNA from the parental and transformed cells suggested that keratin 6a was overexpressed as a result of cell transformation.
Objectives
Our goals were to verify overexpression of keratin 6a in Cd2+- and As3+-transformed UROtsa cells, the corresponding tumor heterotransplants, and human bladder cancer biopsy specimens and to assess what factors may be involved in keratin 6a overexpression.
Methods
Expression was assessed with real-time polymerase chain reaction, Western blot analysis, and immunohistochemistry. We used the effect of addition and deletion of potential growth factors in the cell culture growth medium to assess possible pathways used in keratin 6a overexpression.
Results
Cd2+- and As3+-transformed cells grown in serum-containing growth medium, as well as the derived tumor heterotransplants, overexpressed keratin 6a mRNA and protein compared with UROtsa cells grown in serum-containing growth medium. Immunostaining of keratin 6a in tumor heterotransplants showed focal staining of the tumor cells that was localized to the cytoplasm. Focal immunostaining of keratin 6a was also found in some but not all archival patient specimens of high-grade bladder cancer, confirming translation of the results to human bladder cancer. Studies on growth factor deletion and addition indicated that the level of keratin 6a expression was regulated by the presence of both insulin and epidermal growth factor (EGF). In contrast, growth factors had no effect on the elevated levels of keratin 6a expression found in transformed UROtsa cells.
Conclusions
Our present studies suggest that keratin 6a expression may be a biomarker for malignant urothelial cells that possess an activated EGF and or insulin growth factor pathway.
doi:10.1289/ehp.10279
PMCID: PMC2291003  PMID: 18414623
arsenic; bladder cancer; cadmium; keratin; urothelium; UROtsa
22.  Serum levels of preS antigen (HBpreSAg) in chronic hepatitis B virus infected patients 
Virology Journal  2007;4:93.
Background
Hepatitis B virus (HBV) infection is a serious health problem worldwide. Treatment recommendation and response are mainly indicated by viral load, e antigen (HBeAg) seroconversion, and ALT levels. The S antigen (HBsAg) seroconversion is much less frequent. Since HBeAg can be negative in the presence of high viral replication, preS antigen (HBpreSAg) might be a useful indicator in management of chronic HBV infection.
Results
A new assay of double antibody sandwich ELISA was established to detect preS antigens. Sera of 104 HBeAg-negative and 50 HBeAg-positive chronic hepatitis B patients have been studied and 23 HBeAg-positive patients were enrolled in a treatment follow-up study. 70% of the HBeAg-positive patients and 47% of the HBeAg-negative patients showed HBpreSAg positive. Particularly, in the HBeAg-negative patients, 30 out of 47 HBpreSAg positive patients showed no evidence of viral replication based on HBV DNA copies. A comparison with HBV DNA copies demonstrated that the overall accuracy of the HBpreSAg test could reach 72% for active HBV replication. HBpreSAg changes were well correlated with changes of HBsAg, HBV DNA and ALT levels during the course of IFN-α treatment and follow-up. HBeAg positive patients responded well to treatment when reduction of HBpreSAg levels was more pronounced.
Conclusion
Our results suggested that HBpreSAg could be detected effectively, and well correlated with HBsAg and HBV DNA copies. The reduction of HBpreSAg levels in conjunction with the HBV DNA copies appears to be an improved predictor of treatment outcome.
doi:10.1186/1743-422X-4-93
PMCID: PMC2082030  PMID: 17892580
23.  In vitro assessment of gastrointestinal viability of two photosynthetic bacteria, Rhodopseudomonas palustris and Rhodobacter sphaeroides *  
The objectives of this study were to assess the potential of two photosynthetic bacteria (PSB), Rhodopseudomonas palustris HZ0301 and Rhodobacter sphaeroides HZ0302, as probiotics in aquaculture. The viability of HZ0301 and HZ0302 in simulated gastric transit conditions (pH 2.0, pH 3.0 and pH 4.0 gastric juices) and in simulated small intestinal transit conditions (pH 8.0, with or without 0.3% bile salts) was tested. The effects of HZ0301 and HZ0302 on the viability and permeability of intestinal epithelial cell in primary culture of tilapias, Oreochromis nilotica, were also detected. All the treatments were determined with three replicates. The simulated gastric transit tolerance of HZ0301 and HZ0302 strains was pH-dependent and correspondingly showed lower viability at pH 2.0 after 180 min compared with pH 3.0 and pH 4.0. Both HZ0301 and HZ0302 were tolerant to simulated small intestine transit with or without bile salts in our research. Moreover, there was no significant difference (P>0.05) among three treatments including the control and the groups treated with HZ0301 or HZ0302 both in intestinal epithelial cell viability and membrane permeability, showing no cell damage. In summary, this study demonstrated that HZ0301 and HZ0302 had high capacity of upper gastrointestinal transit tolerance and were relatively safe for intestinal epithelial cells of tilapias.
doi:10.1631/jzus.2007.B0686
PMCID: PMC1963436  PMID: 17726751
Photosynthetic bacteria; Probiotics; Primary culture; Intestinal epithelial cell; Oreochromis nilotica

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