1
|
Safran H, Steinhoff M, Mangray S, Rathore R, King TC, Chai L, Berzein K, Moore T, Iannitti D, Reiss P, Pasquariello T, Akerman P, Quirk D, Mass R, Goldstein L, Tantravahi U. Overexpression of the HER-2/neu oncogene in pancreatic adenocarcinoma. Am J Clin Oncol 2001; 24:496-9. [PMID: 11586103 DOI: 10.1097/00000421-200110000-00016] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Novel systemic treatments are needed in pancreatic cancer. The authors sought to establish the frequency of overexpression of the HER-2/neu oncogene in patients with pancreatic adenocarcinoma to determine the potential role of trastuzumab (Herceptin) as a therapeutic agent in this disease. Tumor specimens from patients with pancreatic adenocarcinoma were analyzed by staining for p185HER2 protein using the DAKO immunohistochemical assay. Patients with and without HER-2/neu overexpression by immunohistochemistry were compared with respect to clinical and pathologic characteristics. HER-2/neu gene amplification was also evaluated by fluorescence in situ hybridization (FISH). Thirty-two of 154 patients (21%) had pancreatic adenocarcinoma that demonstrated HER-2/neu overexpression by immunohistochemistry. At initial diagnosis, 16% of resectable cancers, 17% of locally advanced cancers, and 26% of metastatic cancers were determined to have HER-2/neu overexpression. Three of 11 (27%) patients with HER-2/neu overexpression by immunohistochemistry had gene amplification by FISH. HER-2/neu overexpression occurs in a subset of pancreatic cancer. Evaluation of the efficacy of trastuzumab for patients with pancreatic cancer who overexpress HER-2/neu appears indicated.
Collapse
MESH Headings
- Aged
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Monoclonal, Humanized
- Antineoplastic Agents/therapeutic use
- Carcinoma, Pancreatic Ductal/drug therapy
- Carcinoma, Pancreatic Ductal/genetics
- Carcinoma, Pancreatic Ductal/metabolism
- Carcinoma, Pancreatic Ductal/pathology
- Female
- Humans
- Immunohistochemistry
- In Situ Hybridization, Fluorescence
- Male
- Middle Aged
- Pancreatic Neoplasms/drug therapy
- Pancreatic Neoplasms/genetics
- Pancreatic Neoplasms/metabolism
- Pancreatic Neoplasms/pathology
- Receptor, ErbB-2/genetics
- Receptor, ErbB-2/metabolism
- Trastuzumab
Collapse
|
|
24 |
115 |
2
|
Lv Q, Gong L, Zhang T, Ye J, Chai L, Ni C, Mao Y. Prognostic value of circulating tumor cells in metastatic breast cancer: a systemic review and meta-analysis. Clin Transl Oncol 2016; 18:322-30. [PMID: 26260915 DOI: 10.1007/s12094-015-1372-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 07/28/2015] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Metastatic breast cancer (MBC) remains the main cause of cancer-related death, and the clinical significance and prognostic role of circulating tumor cells (CTCs) in metastatic breast cancer are still controversial. Here, we conducted a meta-analysis to clarify the correlation between CTCs and the clinicopathological features and prognosis of MBC. METHODS We performed a comprehensive search of Pubmed and the ISI Web of Science through December 2014. Only articles that focused on MBC patients and detected CTCs using the CellSearch system were included. The associations between CTCs and survival rate and clinicopathological parameters, including molecular pattern, metastatic region and treatment response, were evaluated. RESULTS This meta-analysis included 24 studies (3701 MBC patients), 13 prospective studies and 11 retrospective studies. We found that CTCs were more frequently detected with HER2 + primary tumors (pooled RR = 0.73, 95 % CI = 0.63-0.84). Additionally, higher CTC numbers indicated a worse treatment response (RR = 0.56, 95 % CI = 0.40-0.79), poorer PFS (RR = 0.64, 95 % CI = 0.56-0.73) and poorer OS (RR = 0.69, 95 % CI = 0.64-0.75) in MBC patients. CONCLUSION Based on these results, we propose that HER2 positivity could be a significant risk factor for the presence of CTCs. Additionally, CTCs have a significant prognostic value for MBC patients. Therefore, CTCs should be continually monitored to guide the treatment of MBC patients, especially those with HER2 + primary tumors.
Collapse
|
Meta-Analysis |
9 |
45 |
3
|
Pettinicchio D, Maroto M, Chai L, Lukk M. Findings from an online survey on the mental health effects of COVID-19 on Canadians with disabilities and chronic health conditions. Disabil Health J 2021; 14:101085. [PMID: 33744158 PMCID: PMC9760304 DOI: 10.1016/j.dhjo.2021.101085] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 02/15/2021] [Accepted: 02/18/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND Although the COVID-19 pandemic has led to worsening mental health outcomes throughout the Canadian population, its effects have been more acute among already marginalized groups, including people with disabilities and chronic health conditions. This paper examines how heightened fears of contracting the virus, financial impacts, and social isolation contribute to declining mental health among this already vulnerable group. OBJECTIVE/HYPOTHESIS This paper investigates how increases in anxiety, stress, and despair are associated with concerns about getting infected, COVID-19-induced financial hardship, and increased social isolation as a result of adhering to protective measures among people with disabilities and chronic health conditions. METHODS This study uses original national quota-based online survey data (n = 1027) collected in June 2020 from people with disabilities and chronic health conditions. Three logistic regression models investigate the relationship between COVID-19's effects on finances, concerns about contracting the virus, changes in loneliness and belonging, and measures taken to combat the spread of COVID-19 and reports of increased anxiety, stress, and despair, net of covariates. RESULTS Models show that increased anxiety, stress, and despair were associated with negative financial effects of COVID-19, greater concerns about contracting COVID-19, increased loneliness, and decreased feelings of belonging. Net of other covariates, increased measures taken to combat COVID-19 was not significantly associated with mental health outcomes. CONCLUSIONS Findings address how the global health crisis is contributing to declining mental health status through heightened concerns over contracting the virus, increases in economic insecurity, and growing social isolation, speaking to how health pandemics exacerbate health inequalities.
Collapse
|
research-article |
4 |
43 |
4
|
Ma Y, Li D, Chai L, Luciani AM, Ford D, Morgan J, Maizel AL. Cloning and characterization of two promoters for the human HSAL2 gene and their transcriptional repression by the Wilms tumor suppressor gene product. J Biol Chem 2001; 276:48223-30. [PMID: 11577094 DOI: 10.1074/jbc.m106468200] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
HSAL2 is a member of a gene family that encodes a group of putative developmental transcription factors. The HSAL gene complex was originally identified on the basis of DNA sequence homology to a region-specific homeotic gene (SAL) in Drosophila. This study reveals a novel, functional 5' exon for HSAL2 and demonstrates that two distinct HSAL2 gene transcripts arise from two overlapping transcription units, resulting in proteins that differ by 25 amino acids. By utilizing functional luciferase reporter assays, two distinct promoters for HSAL2, P1 for the proximal promoter (upstream of exon 1) and P2 for the distal promoter (upstream of exon 1A), were identified. Evaluation of mRNA prevalence and tissue specificity, with particular focus on adult tissues, revealed that production of mRNA from P1 was selective and relatively rare. Production of mRNA from P2 was demonstrably higher and was expressed by a greater number of tissues. In contradistinction, HSAL2 expression directed by P2 was undetectable in some malignant populations as opposed to their normal human counterparts, suggesting a potential role as a tumor suppressor gene. Consensus-binding sites were identified for several transcriptional factors, with multiple sites for WT-1, and Hox-1.3 present within both the P1 and P2 regions. In transient transfection assays, transcription from both HSAL2 P1 and P2 was strikingly repressed by the WT-1 tumor suppressor protein. These findings suggest that an intracellular WT-1/HSAL2 pathway may play a role in development and hematopoiesis.
Collapse
|
|
24 |
35 |
5
|
Chai L, Song YQ, Leung WK. Genetic polymorphism studies in periodontitis and Fcγ receptors. J Periodontal Res 2011; 47:273-85. [PMID: 22117888 DOI: 10.1111/j.1600-0765.2011.01437.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Periodontitis is a complex chronic subgingival plaque-induced inflammatory disease influenced by multiple factors, including genetics, behavior and the environment. Many genetic association studies have been conducted in periodontology. One of the most extensively investigated gene families is the Fcγ receptor gene family, which plays a key role in regulating host immune responses to bacteria. Unlike other genetic polymorphisms reported in periodontology, most Fcγ receptor polymorphisms reported not only have established biological functions but are reported to associate with other autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus. There are, however, few recent reviews summarizing the association of this gene family with periodontitis. This article critically reviews the current understanding of genetic polymorphism studies in periodontitis, then summarizes the research status of Fcγ receptor polymorphisms and periodontitis and also of other genes involved in the regulatory network of Fcγ receptors, with special reference to their anticipated biological roles. Moreover, some possible future research directions in the related area are discussed.
Collapse
|
Review |
14 |
33 |
6
|
Chai L, Wang Y, Wang X, Ma L, Cheng Z, Su L, Liu M. Quantitative source apportionment of heavy metals in cultivated soil and associated model uncertainty. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 215:112150. [PMID: 33756290 DOI: 10.1016/j.ecoenv.2021.112150] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 02/27/2021] [Accepted: 03/11/2021] [Indexed: 06/12/2023]
Abstract
To estimate spatial distribution, source analysis and uncertainty of heavy metals (Pb, Cd, Cr, Hg, As, Cu, Zn, and Ni) based on geographic information system (GIS), positive matrix factorization model (PMF) and bootstrap (BS) using 382 soil samples collected from cultivated soils in Lanzhou. The mean contents of Cd, Hg, Cu, Zn and Ni were high as 1.7,1.7, 2.1, 1.5 and 1.3 times local background values, mean contents of Pb, Cr and As were lower than local background values. However, the mean contents of eight heavy metals were lower environmental quality risk control standard for soil contamination of agricultural soil. Proportions of four sources were identified: Cr was predominantly contributed by natural sources (29.14%), Cu, Zn and Ni was primarily from industrial sources (25.26%), Hg and As were mainly of agricultural sources (27.49%), Pb and Cd mainly came from traffic source and smelting-related activities (18.09%). Uncertainties analysis contained three aspects: bootstrap runs, factor contributions in the PMF solution, and coefficient of variation (CV) values. By combining the four pollution source factors with bootstrap runs, the accuracy of the four pollution source factors were reliable based on PMF model. The median values in the BS runs was considered the most true factor contribution, and the 5th-95th quartile interval represents the variability of each factor, Factor 4 (traffic source) R2 was 0.70 and lower variability. The highest CV value usually means a significantly deviation degree. In this study, the CV values of Cr in Factor 1, Cu, Zn, and Ni in Factor 2, Hg, and As in Factor 3, Pb, and Cd in Factor 4 were lower, indicates a lower deviation degree. and with the lowest content among heavy metals usually was also with the greatest uncertainties. In this study improves understanding of the reduction of heavy metal pollution in cultivated soil, and also serves as reference for pollution source apportionment in other regions.
Collapse
|
|
4 |
26 |
7
|
Chai L, Song YQ, Zee KY, Leung WK. Single nucleotide polymorphisms of complement component 5 and periodontitis. J Periodontal Res 2009; 45:301-8. [PMID: 19909405 DOI: 10.1111/j.1600-0765.2009.01234.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND AND OBJECTIVE Polymorphisms of host defence genes might increase one's risks for periodontitis. This study investigated whether tagging single nucleotide polymorphisms (SNPs) of the gene encoding complement component 5 (C5) are associated with periodontitis in a Hong Kong Chinese population. MATERIAL AND METHODS Eleven tagging SNPs of 229 patients with at least moderate periodontitis and 207 control subjects without periodontitis were genotyped using an i-plexGOLD MassARRAY mass-spectrometry system. RESULTS Genotype AG of SNP rs17611 was more prevalent in the group of periodontitis patients than in the controls (54.6% vs. 41.7%, p = 0.007). The haplotype CGCA of the haplotype block consisting of rs1035029, rs17611, rs25681 and rs992670 was significantly associated with periodontitis in a dominant model (p = 0.001). The SNP rs17611 showed high linkage disequilibrium with rs1035029, rs25681 and rs992670. Smoking was also significantly associated with periodontitis (p = 0.006). CONCLUSION The tagging SNP rs17611 of the C5 gene and smoking may be associated with periodontitis among the Hong Kong Chinese population.
Collapse
|
Research Support, Non-U.S. Gov't |
16 |
23 |
8
|
Ma Y, Singer DB, Gozman A, Ford D, Chai L, Steinhoff MM, Hansen K, Maizel AL. Hsal 1 is related to kidney and gonad development and is expressed in Wilms tumor. Pediatr Nephrol 2001; 16:701-9. [PMID: 11511981 DOI: 10.1007/s004670100624] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2000] [Accepted: 02/28/2001] [Indexed: 11/27/2022]
Abstract
Townes-Brocks syndrome (TBS) is a human genetic disorder with features including urogenital, limb, anal and cardiac malformations associated with mutations of the TBS gene, Hsal 1. To begin to understand the role of the Hsal 1 protein (p140) in both normal development and disease pathogenesis, both message and protein expression were evaluated in specific tissues associated with TBS. DNA sequence information for Hsal 1 predicts that this homeotic, Drosophila homologue (Sal) encodes a zinc-finger protein consistent with a transcription factor. mRNA for Hsal 1 was highly expressed in fetal kidney and brain, with detectable production in thymus and heart. p140 was found in fetal ureteric bud, fetal and postnatal renal tubular epithelium, and renal blastema. In the 14-week fetal testis, the Hsal 1 protein was specifically expressed in the testosterone producing Leydig cells while in adult gonads Hsal 1 was also found in both Leydig and Sertoli cells, spermatogonia of the testis, and granulosa cells of the ovary. Evaluation of Wilms tumor revealed consistently high expression of the gene product in the epithelial and blastemal components. These spatial and temporal patterns of expression for Hsal 1, and the phenotypic effects associated with TBS, suggest that Hsal 1 plays an important role in the development and functional maintenance of the kidney and gonads. Furthermore, the Hsal 1 gene product may play a part in the pathogenesis of specific neoplasms occurring in these organs in addition to its specific role in Townes-Brocks syndrome.
Collapse
|
|
24 |
21 |
9
|
Chai L, Morris JE. Heparan sulfate in the inner limiting membrane of embryonic chicken retina binds basic fibroblast growth factor to promote axonal outgrowth. Exp Neurol 1999; 160:175-85. [PMID: 10630202 DOI: 10.1006/exnr.1999.7195] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
During neural development retinal ganglion cell axons migrate over the retinal basal lamina (inner limiting membrane, ILM) in directed growth toward the optic nerve. We found that both growth rate and distribution density of the ganglion cell axons on isolated cell-free ILM was greatly inhibited by pretreatment with heparitinase but not with chondroitinase ABC. The persistence of radioactively labeled proteoglycans added to the culture medium eliminated residual heparitinase as an explanation for the inhibition. A cell binding assay showed that heparitinase acted on the ILM to influence axonal behavior without apparent inhibition of cell adhesion. These results indicated that the neurite outgrowth promoting activity of the ILM depended on the heparan sulfate (HS) side chains of its proteoglycans. Basic fibroblast growth factor (bFGF) stimulated additional neuronal sprouting and neurite elongation on the ILM. This neurotropic activity of bFGF was inhibited by heparitinase pretreatment of the ILM, suggesting that bFGF bound to HS on the ILM. The activity of bFGF was enhanced by exogenous heparin added to the culture medium; although heparin alone failed to stimulate either neurite extension or neuronal cell sprouting. These results demonstrate that HS in the ILM possesses neurotropic activity for axons of the ganglion cells by binding bFGF for presentation to cell-surface receptors and may, therefore, play a significant role in stimulating axonal outgrowth during development.
Collapse
|
Comparative Study |
26 |
20 |
10
|
Ma Y, Chai L, Cortez SC, Stopa EG, Steinhoff MM, Ford D, Morgan J, Maizel AL. SALL1 expression in the human pituitary-adrenal/gonadal axis. J Endocrinol 2002; 173:437-48. [PMID: 12065233 DOI: 10.1677/joe.0.1730437] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
SALL1 was originally identified on the basis of its DNA sequence homology to the region-specific homeotic gene Sal, in Drosophila melanogaster, which acts as a downstream target of hedgehog/tumor growth factor-beta-like decapentaplegic signals. The SALL1 gene has been associated with the Townes-Brocks Syndrome (TBS), a disorder characterized by multiorgan dysgenesis including renal and genital malformations. In this study, SALL1 message production was evaluated in association with the tissue localization of the protein product of SALL1, p140. SALL1 protein expression was observed in various adult and fetal tissues which elaborate reproductive endocrine hormones. The p140 was localized in specific microanatomic sites of the pituitary, adrenal cortex and the placenta. In the human pituitary, SALL1 protein expression was limited to the adenohypophysis, where it colocalized to those cells producing GH and the gonadotropins, LH and FSH. SALL1 expression was also found in most of the fetal and adult adrenal cortex in addition to the trophoblastic cells of the placenta. This pattern of expression complements prior studies demonstrating p140 in testicular fetal Leydig cells, adult Leydig and Sertoli cells, and granulosa cells of the ovary. The SALL1 protein was also shown here to be highly expressed in trophoblast tumors, which overproduce sex hormones. The expression patterns of SALL1 at multiple levels of the reproductive endocrine axis and the phenotypic effects associated with TBS suggest that SALL1 may have an important role in the interaction of the pituitary-adrenal/gonadal axis during reproduction.
Collapse
|
|
23 |
20 |
11
|
Chin A, Yang Y, Chai L, Wong RWK, Rabie ABM. Effects of medicinal herb salvia miltiorrhiza on osteoblastic cells in vitro. J Orthop Res 2011; 29:1059-63. [PMID: 21319217 DOI: 10.1002/jor.21376] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Accepted: 01/06/2011] [Indexed: 02/04/2023]
Abstract
Sufficient osteoinduction is essential for the success and effectiveness of bone grafting. It was previously found that Salvia Miltiorrhiza (SM), a commonly used Chinese herb increased osteogenesis in vivo. The aim of this study is to investigate the effects of SM on bone cells in vitro, in an attempt to get a better understanding on how SM can promote bone remodeling. MC3T3-E1, an osteoblastic cell line, was cultured with SM for different time intervals (24, 48, and 72 h), whereas the control group consisted of cells cultured without any intervention. The mRNA expression of alkaline phosphatase (ALP), osteocalcin (OCN), osteoprotegerin (OPG), and the receptor activator of nuclear factor kappa B ligand (RANKL) were examined by real-time polymerase chain reaction (qPCR). The expression of ALP showed an early increase at 24 h by 50% (p < 0.001) and at 48 h by 13% (p < 0.001). OCN was decreased by 22% at 24 h (p < 0.001) but increased by 50% and 88% at 48 and 72 h, respectively (p < 0.001). RANKL showed an early increase at the first two time points of 24 and 48 h by 45% (p < 0.001) and 36% (p < 0.01), respectively, while OPG was up-regulated at the latter two time points by 10% at 48 h (p < 0.01) and 68% at 72 h (p < 0.001). Thus, OPG/RANKL was down-regulated first, and then up-regulated. SM enhances bone remodeling by regulating the gene expression of ALP, OCN, OPG, and RANKL. It is a potential medicinal herb to be utilized in the application that requires stimulation in bone cell activities.
Collapse
|
|
14 |
19 |
12
|
Li S, Chai L, Cai Z, Jin L, Chen Y, Wu H, Sun Z. Expression of Survivin and Caspase 3 in Oral Squamous Cell Carcinoma and Peritumoral Tissue. Asian Pac J Cancer Prev 2012; 13:5027-31. [DOI: 10.7314/apjcp.2012.13.10.5027] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
|
|
13 |
19 |
13
|
Chen YZ, Soeda E, Yang HW, Takita J, Chai L, Horii A, Inazawa J, Ohki M, Hayashi Y. Homozygous deletion in a neuroblastoma cell line defined by a high-density STS map spanning human chromosome band 1p36. Genes Chromosomes Cancer 2001; 31:326-32. [PMID: 11433523 DOI: 10.1002/gcc.1151] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Recent molecular studies have shown a relatively high rate of loss of heterozygosity (LOH) in neuroblastoma (NB) as well as other types of tumors in human chromosome band 1p36. To identify candidate tumor suppressor genes in NB, we searched for homozygous deletions in NB cell lines with PCR according to a high-density sequence tagged site (STS)-content map spanning 1p35-36. Among 25 NB cell lines examined, only one cell line, NB-1, showed no signal with 27 STSs in a 480 kb region in 1p36.2. The sequence analysis has revealed that the defective region included seven known genes (E4, KIF1B, SCYA5, PGD, Cortistatin, DFF45, and PEX14), nine expressed sequence tags (ESTs), and two microsatellite markers. These genes are related to apoptosis, an ubiquitin-proteasome pathway, a neuronal microtubule-associated motor molecule, and components of a common translocation machinery. The region between the DFF45 and KIF1B genes was defined as homozygous deletion by Southern blotting. The search in LOH regions with high-density STSs may be useful for the isolation and identification of tumor suppressor genes in other tumors as well as NBs.
Collapse
|
|
24 |
18 |
14
|
Tan YY, Yang YQ, Chai L, Wong RWK, Rabie ABM. Effects of vascular endothelial growth factor (VEGF) on MC3T3-E1. Orthod Craniofac Res 2010; 13:223-8. [DOI: 10.1111/j.1601-6343.2010.01498.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
|
15 |
18 |
15
|
Zhang J, Li H, Chai L, Zhang L, Qu J, Chen T. Quantitative FRET measurement using emission-spectral unmixing with independent excitation crosstalk correction. J Microsc 2014; 257:104-16. [PMID: 25354559 DOI: 10.1111/jmi.12189] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Accepted: 09/20/2014] [Indexed: 11/26/2022]
Abstract
Quantification of fluorescence resonance energy transfer (FRET) needs at least two external samples, an acceptor-only reference and a linked FRET reference, to calibrate fluorescence signal. Furthermore, all measurements for references and FRET samples must be performed under the same instrumental conditions. Based on a novel notion to predetermine the molar extinction coefficient ratio (RC ) of acceptor-to-donor for the correction of acceptor excitation crosstalk, we present here a robust and independent emission-spectral unmixing FRET methodology, Iem-spFRET, which can simultaneously measure the E and RC of FRET sample without any external references, such that Iem-spFRET circumvents the rigorous restriction of keeping the same imaging conditions for all FRET experiments and thus can be used for the direct measurement of FRET sample. We validate Iem-spFRET by measuring the absolute E and RC values of standard constructs with different acceptor-to-donor stoichiometry expressed in living cells. Our results demonstrate that Iem-spFRET is a simple and powerful tool for real-time monitoring the dynamic intermolecular interaction within single living cells.
Collapse
|
Research Support, Non-U.S. Gov't |
11 |
18 |
16
|
Yu H, Li Y, Gao C, Fabien L, Jia Y, Lu J, Silberstein LE, Pinkus GS, Ye K, Chai L, Luo HR. Relevant mouse model for human monocytic leukemia through Cre/lox-controlled myeloid-specific deletion of PTEN. Leukemia 2010; 24:1077-80. [PMID: 20220776 DOI: 10.1038/leu.2010.34] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
Letter |
15 |
17 |
17
|
Chai L, Morris JE. Distribution of heparan sulfate proteoglycans in embryonic chicken neural retina and isolated inner limiting membrane. Curr Eye Res 1994; 13:669-77. [PMID: 7805398 DOI: 10.3109/02713689408999903] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Quantitative distribution of proteoglycans was studied in retinal neural epithelium and its basement membrane (inner limiting membrane). Heparan sulfate proteoglycans (HSPGs) were primarily associated with both inner and outer plexiform (synaptic) layers, and inner limiting membrane (ILM), as determined by autoradiographs of lyase-digested cryosections. Based on distribution of 35S-sulfate-labeled proteoglycans, the isolated ILM contained on average approximately three fourths of its proteoglycans as HSPGs and one fourth as chondroitin sulfate/dermatan sulfate proteoglycans (CS/DSPGs), whereas the remaining retina contained approximately equal amounts of the two proteoglycans (PGs). Immunohistochemical staining indicates that the core proteins of the HSPGs in the ILM are distinct from those of the plexiform layers. The photoreceptor layer, which other studies have shown to contain much of the extracellular CS/DSPGs, was not examined. Enrichment of distinct HSPGs in the ILM and plexiform layers support the conclusion that the HSPGs may be intimately involved in the different developmental events characterizing the two regions: development and extension of ganglion cell axons in the former, synaptogenesis and neuronal function in the latter.
Collapse
|
|
31 |
15 |
18
|
Chai L, Liu S, Mao Q, Wang D, Li X, Zheng X, Xia H. A novel conditionally replicating adenoviral vector with dual expression of IL-24 and arresten inserted in E1 and the region between E4 and fiber for improved melanoma therapy. Cancer Gene Ther 2011; 19:247-54. [DOI: 10.1038/cgt.2011.84] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
|
14 |
15 |
19
|
Chai L, Bosch MA, Moore JM, Rønnekleiv OK. Chronic prenatal cocaine treatment down-regulates mu-opioid receptor mRNA expression in the brain of fetal Rhesus Macaque. Neurosci Lett 1999; 261:45-8. [PMID: 10081923 DOI: 10.1016/s0304-3940(98)01016-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ribonuclease protection assays (RPA) were performed to quantify mu-opioid receptor mRNA expression in specific brain regions of day 70 Rhesus Macaque fetuses that were exposed to cocaine (3 mg/kg) or saline from days 22-70 of gestation. The content of mu-receptor mRNA was high in the diencephalon and moderate in the mesencephalon. In contrast, mu-receptor mRNA was lightly expressed in areas such as the frontal cortex, striatum and the temporal lobe. The content of mu-opioid receptor mRNA was significantly higher in the diencephalon than in other brain regions (P < 0.001; n = 4). Cocaine exposure significantly decreased the expression of mu-receptor mRNA in the fetal diencephalon (P < 0.05; n = 4 in each group). Our data would indicate that prolonged gestational cocaine exposure causes mu-opioid receptor mRNA down-regulation in specific brain regions of the fetus.
Collapse
|
|
26 |
14 |
20
|
Chai L, Ni JQ, Diehl C, Kilic I, Heber A, Chen Y, Cortus E, Bogan B, Lim T, Ramirez-Dorronsoro JC, Chen L. Ventilation rates in large commercial layer hen houses with two-year continuous monitoring. Br Poult Sci 2012; 53:19-31. [DOI: 10.1080/00071668.2011.643766] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
|
13 |
14 |
21
|
Chai L, Song YQ, Zee KY, Leung WK. SNPs of Fc-gamma receptor genes and chronic periodontitis. J Dent Res 2010; 89:705-10. [PMID: 20439936 DOI: 10.1177/0022034510365444] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Genetic polymorphisms of host defense genes might increase risk for periodontitis. This case-control study investigated whether 102 single-nucleotide polymorphisms (SNPs) in Fc gamma receptor (FCGR) genes are associated with chronic periodontitis. Cases were 190 Hong Kong Chinese patients with severe chronic periodontitis, and there were 169 periodontitis-free individuals as controls. Genotype CC and allele C of rs445509 (p < 0.0001, OR = 0.30) of FCGR3A were significantly more prevalent among control individuals than among cases, after adjustment for age, sex, and smoking. Smoking was significantly associated with chronic periodontitis (p = 0.003, OR = 3.35). Within the limitations of this study, SNP rs445509 of FCGR3A seem to be negatively associated, while smoking was positively associated, with severe chronic periodontitis among Hong Kong Chinese.
Collapse
|
Research Support, Non-U.S. Gov't |
15 |
13 |
22
|
Halifu Y, Liang JQ, Zeng XW, Ding Y, Zhang XY, Jin TB, Yakeya B, Abudu D, Zhou YM, Liu XM, Hu FX, Chai L, Kang XJ. Wnt1 and SFRP1 as potential prognostic factors and therapeutic targets in cutaneous squamous cell carcinoma. GENETICS AND MOLECULAR RESEARCH 2016; 15:gmr8187. [PMID: 27420949 DOI: 10.4238/gmr.15028187] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The Wnt signaling pathway plays a key role in insurgence and progression of many different forms of cancer. Some crucial components of the Wnt pathway have been proposed to be novel targets for cancer therapy. To date, the Wnt signaling pathway has not been studied in cutaneous squamous cell carcinoma (CSCC). This study was designed to investigate the expression of Wnt1 and SFRP1 from the Wnt pathway in CSCC. Tissue samples were obtained from 35 patients with CSCC and 30 controls admitted to the Xinjiang Uygur Autonomous Region People's Hospital at Urumchi City, China. Gene and protein expressions of Wnt1 and SFRP1 were quantified by immunohistochemistry and western blotting. Wnt1 expression was significantly higher (P < 0.05) in CSCC samples than in normal skin cells of the control subjects; in contrast, SFRP1 expression was significantly lower in CSCC tissues than that in tissues of control subjects (P < 0.05). Moreover, Wnt1 expression (P < 0.05) was found to be correlated with histopathological differentiation in CSCC, and negatively correlated with SFRP1 expression in CSCC (rs = -0.473, P = 0.015). Therefore, we concluded that Wnt1 and SFRP1 play important roles in the development of CSCC and could be potent markers for diagnosis, prevention, and therapy of CSCC.
Collapse
|
Journal Article |
9 |
11 |
23
|
Ban G, Hou Y, Shen Z, Jia J, Chai L, Ma C. Potential Biomedical Limitations of Graphene Nanomaterials. Int J Nanomedicine 2023; 18:1695-1708. [PMID: 37020689 PMCID: PMC10069520 DOI: 10.2147/ijn.s402954] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 03/23/2023] [Indexed: 04/07/2023] Open
Abstract
Graphene-family nanomaterials (GFNs) possess mechanical stiffness, optical properties, and biocompatibility making them promising materials for biomedical applications. However, to realize the potential of graphene in biomedicine, it must overcome several challenges that arise when it enters the body's circulatory system. Current research focuses on the development of tumor-targeting devices using graphene, but GFNs accumulated in different tissues and cells through different pathways, which can cause toxic reactions leading to cell apoptosis and body dysfunction when the accumulated amount exceeds a certain limit. In addition, as a foreign substance, graphene can induce complex inflammatory reactions with immune cells and inflammatory factors, potentially enhancing or impairing the body's immune function. This review discusses the biomedical applications of graphene, the effects of graphene materials on human immune function, and the biotoxicity of graphene materials.
Collapse
|
Review |
2 |
10 |
24
|
Lagemann M, George R, Chai L, Walsh LJ. Activation of ethylenediaminetetraacetic acid by a 940 nm diode laser for enhanced removal of smear layer. AUST ENDOD J 2013; 40:72-5. [PMID: 25244221 DOI: 10.1111/aej.12039] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Laser enhancement of ethylenediaminetetraacetic acid with cetrimide (EDTAC) has previously been shown to increase removal of smear layer, for middle-infrared erbium lasers. This study evaluated the efficiency of EDTAC activation using a near-infrared-pulsed 940 nm laser delivered by plain fibre tips into 15% EDTAC or 3% hydrogen peroxide. Root canals in 4 groups of 10 single roots were prepared using rotary files, with controls for the presence and absence of smear layer. After laser treatment (80 mJ pulse(-1) , 50 Hz, 6 cycles of 10 s), roots were split and the apical, middle and coronal thirds of the canal were examined using scanning electron microscopy, with the area of dentine tubules determined by a validated quantitative image analysis method. Lasing EDTAC considerably improved smear layer removal, while lasing into peroxide gave minimal smear layer removal. The laser protocol used was more effective for smear layer removal than the 'gold standard' protocol using EDTAC with sodium hypochlorite (NaOCl). In addition, lasers may also provide a benefit through photothermal disinfection. Further research is needed to optimise irrigant activation protocols using near-infrared diode lasers of other wavelengths.
Collapse
|
Journal Article |
12 |
10 |
25
|
Tang P, Gao C, Li A, Aster J, Sun L, Chai L. Differential roles of Kras and Pten in murine leukemogenesis. Leukemia 2012. [PMID: 23183424 DOI: 10.1038/leu.2012.316] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
|
Letter |
13 |
10 |