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MacDonnell C, Galorport C, Telford JJ, Lam E, Enns RA. A176 SMALL GASTROINTESTINAL STROMAL TUMORS (GISTS): A RETROSPECTIVE ANALYSIS OF EUS SURVEILLANCE. J Can Assoc Gastroenterol 2018. [DOI: 10.1093/jcag/gwy009.176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Tagawa S, Faltas B, Lam E, Saylor P, Bardia A, Hajdenberg J, Morgans A, Lim E, Kalinsky K, Petrylak D, Guarino M, Galsky M, Maliakal P, Mudenda B, Sharkey R, Wegener W, Goldenberg D. Sacituzumab govitecan (IMMU-132) for patients with pretreated metastatic urothelial uancer (UC): interim results. Ann Oncol 2017. [DOI: 10.1093/annonc/mdx371.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Lam E, Partridge SR, Allman-Farinelli M. Strategies for successful recruitment of young adults to healthy lifestyle programmes for the prevention of weight gain: a systematic review. Obes Rev 2016; 17:178-200. [PMID: 26663091 DOI: 10.1111/obr.12350] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 09/28/2015] [Accepted: 09/30/2015] [Indexed: 12/12/2022]
Abstract
Recruiting healthy young adults, aged 18-35, to lifestyle programmes for prevention of weight gain is challenging but important given their increasing rates of obesity. This review aimed to examine the success of different recruitment strategies. A systematic literature search identified 26 separate studies using 10 electronic databases. Participant characteristics and efficacy of interventions were well reported in all studies, but reporting of recruitment procedures, costs, times and effectiveness was minimal. Of those reporting recruitment, both active (e.g. face-to-face) and passive (e.g. print-media and mass-mailings) approaches were identified with the latter most frequently employed. Novel strategies such as social media and marketing approaches were identified. Television and radio have potentially high reach but low efficiency with high cost compared with mass-mailings which yield high numbers of participants. Marketing campaigns appeared to be a promising approach. Incentives demonstrated enhanced recruitment. The use of formative research to guide recruitment strategies for interventions is recommended. Reporting of success, cost and timelines for recruitment should be included in reporting of future trials. This first synthesis of recruitment information can be used to inform recruitment frameworks for lifestyle programmes seeking to attract young adults.
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Kargarfard M, Shariat A, Lam E, Shaw B, Shaw I, Shariat A, Nayyeri F. Prevalence and Perceptions Toward Anabolicandrogenic Steroid Use Amongst University Students. ACTA MEDICA BULGARICA 2015. [DOI: 10.1515/amb-2015-0019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Summary
Anabolic-androgenic steroids (AASs) are highly sought-after in order to achieve muscle growth and better physical attributes. The study was conducted to measure the prevalence and attitudes towards the use of AASs among university students. 1008 male students from Isfahan University, Iran, between the ages of 18 and 25 years (23.3 ± 1.2 years) completed a questionnaire that investigated participation in bodybuilding, level of sport competition, participation in sports and recreational activities, AASs use, prevalence, knowledge among users, attitudes, as well as intent to continue using AASs in the future. 8% of respondents had used AASs and 6% currently use AASs. 71% of users believed using only a small amount of AASs or using AASs with anti-toxic drugs would not result in any harm, 10% indicated that AASs were harmless and 19% admitted to taking AASs despite knowing the adverse effects. 33% of respondents believed that they needed to use AASs to ensure athletic success and 26% believed that athletes should be allowed to use AASs without consequence. The prevalent use of AASs is a public health concern which implies that educational programmes at university level are needed to educate students about the adverse effects of AASs use
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Nikitenko NA, Speiseder T, Lam E, Rubtsov PM, Tonaeva KD, Borzenok SA, Dobner T, Prassolov VS. Regulation of Human Adenovirus Replication by RNA Interference. Acta Naturae 2015. [DOI: 10.32607/20758251-2015-7-3-100-107] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Adenoviruses cause a wide variety of human infectious diseases. Adenoviral conjunctivitis and epidemic keratoconjunctivitis are commonly associated with human species D adenoviruses. Currently, there is no sufficient or appropriate treatment to counteract these adenovirus infections. Thus, there is an urgent need for new etiology-directed therapies with selective activity against human adenoviruses. To address this problem, the adenoviral early genes E1A and E2B (viral DNA polymerase) seem to be promising targets. Here, we propose an effective approach to downregulate the replication of human species D adenoviruses by means of RNA interference. We generated E1A expressing model cell lines enabling fast evaluation of the RNA interference potential. Small interfering RNAs complementary to the E1A mRNA sequences of human species D adenoviruses mediate significant suppression of the E1A expression in model cells. Furthermore, we observed a strong downregulation of replication of human adenoviruses type D8 and D37 by small hairpin RNAs complementary to the E1A or E2B mRNA sequences in primary human limbal cells. We believe that our results will contribute to the development of efficient anti-adenoviral therapy.
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Nikitenko NA, Speiseder T, Lam E, Rubtsov PM, Tonaeva KD, Borzenok SA, Dobner T, Prassolov VS. Regulation of Human Adenovirus Replication by RNA Interference. Acta Naturae 2015; 7:100-7. [PMID: 26483965 PMCID: PMC4610170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Adenoviruses cause a wide variety of human infectious diseases. Adenoviral conjunctivitis and epidemic keratoconjunctivitis are commonly associated with human species D adenoviruses. Currently, there is no sufficient or appropriate treatment to counteract these adenovirus infections. Thus, there is an urgent need for new etiology-directed therapies with selective activity against human adenoviruses. To address this problem, the adenoviral early genes E1A and E2B (viral DNA polymerase) seem to be promising targets. Here, we propose an effective approach to downregulate the replication of human species D adenoviruses by means of RNA interference. We generated E1A expressing model cell lines enabling fast evaluation of the RNA interference potential. Small interfering RNAs complementary to the E1A mRNA sequences of human species D adenoviruses mediate significant suppression of the E1A expression in model cells. Furthermore, we observed a strong downregulation of replication of human adenoviruses type D8 and D37 by small hairpin RNAs complementary to the E1A or E2B mRNA sequences in primary human limbal cells. We believe that our results will contribute to the development of efficient anti-adenoviral therapy.
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Choi SL, Loghin C, Garhyan P, Knadler MP, Lam E, Sinha V, Porksen N, Linnebjerg H. A single-dose pharmacokinetic study of basal insulin peglispro (BIL) in subjects with hepatic impairment. DIABETOL STOFFWECHS 2015. [DOI: 10.1055/s-0035-1549750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Borisjuk N, Chu P, Gutierrez R, Zhang H, Acosta K, Friesen N, Sree KS, Garcia C, Appenroth KJ, Lam E. Assessment, validation and deployment strategy of a two-barcode protocol for facile genotyping of duckweed species. PLANT BIOLOGY (STUTTGART, GERMANY) 2015; 17 Suppl 1:42-9. [PMID: 25115915 DOI: 10.1111/plb.12229] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 06/01/2014] [Indexed: 05/13/2023]
Abstract
Lemnaceae, commonly called duckweeds, comprise a diverse group of floating aquatic plants that have previously been classified into 37 species based on morphological and physiological criteria. In addition to their unique evolutionary position among angiosperms and their applications in biomonitoring, the potential of duckweeds as a novel sustainable crop for fuel and feed has recently increased interest in the study of their biodiversity and systematics. However, due to their small size and abbreviated structure, accurate typing of duckweeds based on morphology can be challenging. In the past decade, attempts to employ molecular barcoding techniques for species assignment have produced promising results; however, they have yet to be codified into a simple and quantitative protocol. A study that compiles and compares the barcode sequences within all known species of this family would help to establish the fidelity and limits of this DNA-based approach. In this work, we compared the level of conservation between over 100 strains of duckweed for two intergenic barcode sequences derived from the plastid genome. By using over 300 sequences publicly available in the NCBI database, we determined the utility of each of these two barcodes for duckweed species identification. Through sequencing of these barcodes from additional accessions, 30 of the 37 known species of duckweed could be identified with varying levels of confidence using this approach. From our analyses using this reference dataset, we also confirmed two instances where mis-assignment of species has likely occurred. Potential strategies for further improving the scope of this technology are discussed.
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Kappos L, Bar-Or A, Cree B, Fox R, Giovannoni G, Gold R, Vermersch P, Lam E, Pohlmann H, Wallström E. Siponimod (BAF312) for the treatment of secondary progressive multiple sclerosis: Design of the phase 3 EXPAND trial. Mult Scler Relat Disord 2014. [DOI: 10.1016/j.msard.2014.09.185] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Martin PM, Yang X, Robin N, Lam E, Rabinowitz JS, Erdman CA, Quinn J, Weiss LA, Hamilton SP, Kwok PY, Moon RT, Cheyette BNR. A rare WNT1 missense variant overrepresented in ASD leads to increased Wnt signal pathway activation. Transl Psychiatry 2013; 3:e301. [PMID: 24002087 PMCID: PMC3784764 DOI: 10.1038/tp.2013.75] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 07/23/2013] [Accepted: 07/24/2013] [Indexed: 01/01/2023] Open
Abstract
Wnt signaling, which encompasses multiple biochemical pathways that regulate neural development downstream of extracellular Wnt glycoprotein ligands, has been suggested to contribute to major psychiatric disorders including autism spectrum disorders (ASD). We used next-generation sequencing and Sequenom genotyping technologies to resequence 10 Wnt signaling pathway genes in 198 ASD patients and 240 matched controls. Results for single-nucleotide polymorphisms (SNPs) of interest were confirmed in a second set of 91 ASD and 144 control samples. We found a significantly increased burden of extremely rare missense variants predicted to be deleterious by PolyPhen-2, distributed across seven genes in the ASD sample (3.5% in ASD vs 0.8% in controls; Fisher's exact test, odds ratio (OR)=4.37, P=0.04). We also found a missense variant in WNT1 (S88R) that was overrepresented in the ASD sample (8 A/T in 267 ASD (minor allele frequency (MAF)=1.69%) vs 1 A/T in 377 controls (MAF=0.13%), OR=13.0, Fisher's exact test, P=0.0048; OR=8.2 and P=0.053 after correction for population stratification). Functional analysis revealed that WNT1-S88R is more active than wild-type WNT1 in assays for the Wnt/β-catenin signaling pathway. Our findings of a higher burden in ASD of rare missense variants distributed across 7 of 10 Wnt signaling pathway genes tested, and of a functional variant at the WNT1 locus associated with ASD, support that dysfunction of this pathway contributes to ASD susceptibility. Given recent findings of common molecular mechanisms in ASD, schizophrenia and affective disorders, these loci merit scrutiny in other psychiatric conditions as well.
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Lam E, Ramke M, Groos S, Warnecke G, Heim A. A differentiated porcine bronchial epithelial cell culture model for studying human adenovirus tropism and virulence. J Virol Methods 2011; 178:117-23. [PMID: 21907242 DOI: 10.1016/j.jviromet.2011.08.025] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 08/18/2011] [Accepted: 08/22/2011] [Indexed: 10/17/2022]
Abstract
The species specificity of human adenoviruses (HAdV) almost precludes studying virulence and tropism in animal models, e.g. rodent models, or derived tissue and cell culture models. However, replication of HAdV type 5 (HAdV-C5) has been shown after intravenous injection in swine. In order to study adenovirus replication in airway tissue propagation of bronchial epithelial cells from porcine lungs was established. These primary cells proved to be fully permissive for HAdV-C5 infection in submerged culture, demonstrating efficient HAdV genome replication, infectious viral particle release (1.07×10(8) TCID(50)/ml±6.63×10(7)) and development of cytopathic effect (CPE). Differentiation of porcine bronchial epithelial cells was achieved at the air-liquid interface on collagen I coated 0.4μm polyester membranes. Morphology, expression of tubulin and occludin, the development of tight-junctions and cilia were similar to human bronchial epithelial cells. Infection with HAdV-C5 from the basolateral side resulted in release of infectious virus progeny (2.05×10(7) TCID(50)/ml±2.39×10(7)) to the apical surface as described recently in human bronchial epithelial cells, although complete CPE was not observed. Differentiated porcine bronchial epithelial cells hold promise as a novel method for studying the virulence and pathophysiology of pneumonia associated HAdV types.
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Ishikawa T, Watanabe N, Nagano M, Kawai-Yamada M, Lam E. Bax inhibitor-1: a highly conserved endoplasmic reticulum-resident cell death suppressor. Cell Death Differ 2011; 18:1271-8. [PMID: 21597463 DOI: 10.1038/cdd.2011.59] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
In spite of fundamental differences between plant and animal cells, it is remarkable that some cell death regulators that were identified to control cell death in metazoans can also function in plants. The fact that most of these proteins do not have structural homologs in plant genomes suggests that they may be targeting a highly conserved 'core' mechanism with conserved functions that is present in all eukaryotes. The ubiquitous Bax inhibitor-1 (BI-1) is a common cell death suppressor in eukaryotes that has provided a potential portal to this cell death core. In this review, we will update the current status of our understanding on the function and activities of this intriguing protein. Genetic, molecular and biochemical studies have so far suggested a consistent view that BI-1 is an endoplasmic reticulum (ER)-resident transmembrane protein that can interact with multiple partners to alter intracellular Ca(2+) flux control and lipid dynamics. Functionally, the level of BI-1 protein has been hypothesized to have the role of a rheostat to regulate the threshold of ER-stress inducible cell death. Further, delineation of the cell death suppression mechanism by BI-1 should shed light on an ancient cell death core-control pathway in eukaryotes, as well as novel ways to improve stress tolerance.
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Lam E, Malkin R. Reconstruction of the chloroplast noncyclic electron transport pathway from water to NADP with three integral protein complexes. Proc Natl Acad Sci U S A 2010; 79:5494-8. [PMID: 16593225 PMCID: PMC346930 DOI: 10.1073/pnas.79.18.5494] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
RECONSTRUCTION OF PHOTOSYNTHETIC NONCYCLIC ELECTRON TRANSPORT FROM WATER TO NADP HAS BEEN ACCOMPLISHED BY USING THREE INTEGRAL PROTEIN COMPLEXES ISOLATED FROM CHLOROPLAST THYLAKOID MEMBRANES: photosystems I and II and the cytochrome b(6)-f complex. This system shows an absolute dependence on the presence of all three protein complexes for NADP reduction, in addition to plastocyanin, ferredoxin, and ferredoxin-NADP reductase. The reconstructed system was found to be sensitive to low concentrations of known inhibitors of noncyclic electron transport. Depletion of the Rieske iron-sulfur center and bound plastoquinone from the cytochrome b(6)-f complex resulted in an inhibition of the photoreduction of NADP.
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Acoba JD, Nakasone R, Young KB, Kagihara JM, Lam E. Validation of ADJUVANT! for colon cancer in a multiethnic population. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.e14004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Strom A, Hartman J, Lam E, Lin C, Gustafsson J, Gustafsson J. Function of HES6 an Inhibitor of HES1, in the Breast Cancer Cell Lines T47D and MCF-7 Is to Up-Regulate E2F-1 and Increased Proliferation. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-09-2153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Hormone resistance remains as a major obstacle in breast cancer treatment. The majority of breast tumors are dependent on estrogens to grow, therefore anti-estrogens such as Tamoxifen is an effective treatment option. We have found that a transcription factor Hes6, earlier described in the nervous tissue, is up-regulated in hormone-independent breast cancer cells compared to normal estrogen sensitive breast cancer cells. By using a lenti-virus system, we have over-expressed Hes6 in T47D cells which are estrogen sensitive. This resulted in increased proliferation. We also found that estrogen treatment of MCF-7 breast cancer cells induced expression of endogenous Hes6 in the G1-phase. We could not find any binding of estrogen receptor α to the HES6 gene but instead found a binding site up-steam of the promoter in the ASCL1 gene. ASCL1 is a known inducer of HES6 and we are showing that ASCL1 is up-regulated by 17β-estradiol in MCF-7 cells. To find the mechanism behind the tumorogenic effects of Hes6, we analysed important factors of the cell-cycle. We found that the G1-phase factor E2F-1 was up-regulated in response to increased Hes6 expression. Since HES6 have been shown to be an inhibitor of HES1, this is in agreement with a previous study where we found that HES1 inhibited proliferation by binding to the promoter of and down-regulating E2F-1 expression. E2F-1 is an important limiting factor in late G1-phase of the cell cycle and can drive cell proliferation.We believe that the HES1-HES6 interplay is important in antiestrogen-resistant breast cancer. Studies are now ongoing to investigate if Hes6 is up-regulated in estrogen-independent human breast cancer samples.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2153.
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Pilz K, Jobst A, Lam E, Lüdecke J, van Smaalen S, Bao J, Bietsch W, Schwoerer M. The glass transition in twinned ((phenyl)4As)2C60Cl crystals. Z KRIST-CRYST MATER 2009. [DOI: 10.1524/zkri.217.2.78.20629] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
We have studied the crystal structure of ((phenyl)4As)2C60Cl at room temperature and below the phase transition at Tc
= 125 K by single-crystal x-ray diffraction. At room temperature tetragonal lattice parameters were found as a = b = 12.588(1)Å and c = 20.345(1)Å. At T = 120 K the lattice parameters were determined as a = b = 12.5060(1)Å and c = 20.4420(1)Å. The room temperature and low-temperature structures were found to be isostructural, with space group I4/m. Structure refinements were performed with restrictions on the C60 molecules according to the noncrystallographic isohedral point symmetry Ih
. Derivations from this symmetry could not be found, suggesting that any possible Jahn-Teller distortion of the C60 radical anions will be smaller than 0.01Å. The phase transition observed in ESR at Tc
= 125 K is proposed to be a glass transition. At room temperature there is dynamic disorder between two orientations of the C60 molecules as they are related by the 4-fold rotation. Below Tc
the disorder becomes static. Two types of twinning have been observed in different crystals. The first type is represented by a rotation over 180 about [1,1,1] axis. It results in different orientations of the 4-fold unique axes with angles of 82.4 degrees between them. Secondly, merohedral twinning was observed corresponding to the two orientations of the structure with 4/m symmetry on the tetragonal lattice. Both twinnings result in extra orientations of the C60 molecules, and they should be taken into account, when analysing the anisotropy of the physical properties of crystals of this compound.
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Lam E, Tredget E, Ghahary A. 019
Stratifin-Induced MMP-1 in Fibroblast is Mediated by c-Fos and P38 MAPK Activation. Wound Repair Regen 2008. [DOI: 10.1111/j.1067-1927.2005.130215s.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Krol J, Lam E, Coombes C. Critical role of FoxO3a transcription factor in response to therapy with EGFR inhibitors, gefitinib and lapatinib, in breast cancer. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.21018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
21018 Background: Inhibition of the EGF-receptor is a potential therapeutic strategy for breast cancer. The PI3-K/PKB signalling pathway plays an important role in cell proliferation, survival and malignant transformation. The Forkhead box group O transcriptional factor, FoxO3a, is a direct downstream target of PKB. Here we studied the role of the FoxO3a in response to the EGFR inhibitors Gefitinib and Lapatinib. Methods: Response of breast cancer cell lines to treatment with Gefitinib and Lapatinib was evaluated by proliferation assay and FACS analysis. Expression of FoxO3a and its downstream targets was analysed using Western blotting. Sub-cellular localisation of FoxO3a was analysed by confocal microscopy. FoxO3a mRNA level was measured by RTq-PCR. siRNA transfections were performed using Oligofectamine reagent. Immunohistological staining was performed on patient samples to validate our findings. Results: Treatment of a panel of breast cancer cell lines with both inhibitors resulted in decreased proliferation due to G1-arrest and apoptosis in two sensitive cell-lines, BT474 and SKBR3. Western blot analysis revealed that response to the treatment was associated with a decrease in PKB and FoxO3a phosphorylation and thus the nuclear relocalisation of FoxO3a. Confocal microscopy confirmed that treatment induced nuclear translocation of FoxO3a only in sensitive but not resistant cells. This relocation of FoxO3a was accompanied by an induction of FoxO3a mRNA and its principal targets, p27kip1 and Bim. Transfection of the sensitive BT474 cells with FoxO3a specific siRNA resulted in a significant reduction in FoxO3a protein expression and Gefitinib-induced cell death. Comparison of immunohistochemical staining of biopsies from breast cancer patients before and after Gefitinib treatment revealed that therapy resulted in a significant increase in nuclear FoxO3a staining. Conclusion: Our results demonstrate for the first time that the EGFR-family inhibitors, Gefitinib and Lapatinib, specifically target FoxO3a to induce cell cycle arrest and apoptosis. This finding helps to define the mechanism of action of Gefitinib and Lapatinib and may provide novel insights into the molecular basis for resistance to these inhibitors. No significant financial relationships to disclose.
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Sekeres M, Kantarjian H, List A, Lam E, Leveque J, Paquette R, Maciejewski J. P127 Prospective cross-sectional analysis of cytopenias and transfusion needs of MDS patients in the USA. Leuk Res 2007. [DOI: 10.1016/s0145-2126(07)70197-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Lui G, Lee N, Ip M, Choi KW, Tso YK, Lam E, Chau S, Lai R, Cockram CS. Cryptococcosis in apparently immunocompetent patients. QJM 2006; 99:143-51. [PMID: 16504989 DOI: 10.1093/qjmed/hcl014] [Citation(s) in RCA: 158] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Few reports have described the clinical and microbiological features of cryptococcosis in immunocompetent patients. AIM To compare clinical presentations and outcomes of cryptococcosis in immunocompetent vs. immunocompromised patients. DESIGN Retrospective case series. METHODS All culture- or histology-confirmed cases (n = 46) of cryptococcosis in two acute hospitals in Hong Kong (1995-2005) were included. Clinical presentations, rates of fungaemia, cerebrospinal fluid (CSF) parameters and clinical outcomes were recorded. RESULTS Twenty patients (43.5%) were apparently immunocompetent, 17 (37.0%) had predisposing factors other than HIV infection, and 9 (19.6%) were HIV-positive. Thirty-one (67.4%) presented with meningitis, four (8.7%) with pulmonary cryptococcosis, and 11 (23.9%) with extraneural, extrapulmonary cryptococcosis. Of the immunocompetent patients with retrievable isolates (n = 8), three (37.5%) were Cryptococcus gattii; all isolates (n = 6) from immunocompromised patients were Cryptococcus neoformans var. grubii. Immunocompetent patients more commonly presented with meningitis (80.0% vs. 47.1%, p = 0.03), and tended toward lower rates of fungaemia (10.0% vs. 35.3%, p = 0.06) and mortality (25.0% vs. 52.9%, p = 0.06). Death was associated with fungaemia (p = 0.01) and underlying malignancy (p < 0.01). In cryptococcal meningitis, immunocompetent patients had longer mean time from illness onset to presentation (34.4 vs. 12.6 days, p = 0.02), more intense inflammatory responses (CSF: white blood cells 108 vs. 35 x 10(9)/l, p = 0.03; protein 1.61 g/l vs. 0.79 g/l, p = 0.07), less fungaemia (0% vs. 26.7%, p = 0.04) and more satisfactory clinical outcomes (81.3% vs. 46.7%, p = 0.04). DISCUSSION A substantial proportion of patients with cryptococcosis are apparently immunocompetent. C. neoformans var. grubii and C. gattii are the common causes. Immunocompetent patients tend to present with localized, indolent neurological disease, with more intense inflammatory responses but better clinical outcomes.
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Wong WR, Lam E, Huang RC, Wong RS, Morris C, Hackett J. Applications, and efficient large-scale production, of recombinant human epidermal growth factor. Biotechnol Genet Eng Rev 2002; 18:51-71. [PMID: 11530698 DOI: 10.1080/02648725.2001.10648008] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Pontier D, Miao ZH, Lam E. Trans-dominant suppression of plant TGA factors reveals their negative and positive roles in plant defense responses. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2001; 27:529-38. [PMID: 11576436 DOI: 10.1046/j.1365-313x.2001.01086.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Salicylic acid (SA) is a key regulator for the induction of systemic acquired resistance (SAR), and NPR1 is a critical mediator for the biological effects of SA. Physical interactions between NPR1 and TGA factors, a conserved family of basic-leucine-zipper (bZip) proteins in plants, have suggested a role for these transcription factors in mediating SAR induction via the regulation of defense genes. To elucidate this function, we constructed a trans-dominant mutant that specifically eliminates DNA-binding activities of this class of bZip proteins in transgenic tobacco plants. Our results demonstrate that the loss of TGA DNA-binding activities is correlated with suppression of two xenobiotic-responsive genes, GNT35 and STR246, and enhanced induction of pathogenesis-related (PR) genes by SA. In addition, these TGA-suppressed plants exhibited higher levels of PR gene induction by pathogen challenge and an enhanced SAR. These results suggest that TGA transcription factors serve both negative and positive regulatory roles in mediating plant defense responses.
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Lenigk R, Lam E, Lai A, Wang H, Han Y, Carlier P, Renneberg R. Enzyme biosensor for studying therapeutics of Alzheimer's disease. Biosens Bioelectron 2001; 15:541-7. [PMID: 11419651 DOI: 10.1016/s0956-5663(00)00078-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
An electrochemical method for the investigation and comparison of anti-Alzheimer medications that is based on the inhibition of the acetylcholinesterase is presented. The developed amperometric biosensor determines the in-vitro inhibition of the acetylcholinesterase that is co-immobilized with choline oxidase on the working electrode surface of a three-electrode system using gel entrapment. The sensor has been applied to determine the IC50 values of two known and one newly developed Alzheimer remedy. A simultaneous measurement with the photometric standard method shows the applicability of our method for fast drug screening.
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Lam E, Kato N, Lawton M. Programmed cell death, mitochondria and the plant hypersensitive response. Nature 2001; 411:848-53. [PMID: 11459068 DOI: 10.1038/35081184] [Citation(s) in RCA: 533] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The plant response to attempted infection by microbial pathogens is often accompanied by rapid cell death in and around the initial infection site, a reaction known as the hypersensitive response. This response is associated with restricted pathogen growth and represents a form of programmed cell death (PCD). Recent pharmacological and molecular studies have provided functional evidence for the conservation of some of the basic regulatory mechanisms underlying the response to pathogens and the activation of PCD in animal and plant systems. In animals, the mitochondrion integrates diverse cellular stress signals and initiates the death execution pathway, and studies indicate a similar involvement for mitochondria in regulating PCD in plants. But many of the cell-death regulators that have been characterized in humans, worms and flies are absent from the Arabidopsis genome, indicating that plants probably use other regulators to control this process.
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Kato N, Lam E. Detection of chromosomes tagged with green fluorescent protein in live Arabidopsis thaliana plants. Genome Biol 2001; 2:RESEARCH0045. [PMID: 11737944 PMCID: PMC60307 DOI: 10.1186/gb-2001-2-11-research0045] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2001] [Revised: 09/05/2001] [Accepted: 09/09/2001] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Structural and dynamic studies of chromosomes tagged with green fluorescent protein (GFP) in yeast and cultured animal cells have revealed some surprises. Although this technology can be very powerful, only a few studies using this approach with developed multicellular systems have been reported for the study of chromatin behavior in situ. RESULTS We established vectors and conditions to visualize tagged loci stably inserted in the Arabidopsis genome via GFP fused to a bacterial DNA-binding protein. Using this system, three-dimensional coordinates for tagged loci within nuclei from cells of a live plant can be directly determined with concomitant visualization of the position of the nucleolus. Chromosome polyploidization in epidermal cells at the elongation zone of the root in transgenic plants can be visualized in situ using this technique. CONCLUSION We have established that GFP fusion with DNA-binding proteins can be used in conjunction with concatameric binding-site arrays to track genomic loci in living Arabidopsis plants. It should now be feasible to study the mechanisms of organization and dynamics of chromatin in specific cell types during various times of plant development, taking advantage of the well developed genetic systems and resources available for Arabidopsis.
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