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Pini J, Kueper J, Hu YD, Kawasaki K, Yeung P, Tsimbal C, Yoon B, Carmichael N, Maas RL, Cotney J, Grinblat Y, Liao EC. ALX1-related frontonasal dysplasia results from defective neural crest cell development and migration. EMBO Mol Med 2022; 14:e16289. [PMID: 35795978 DOI: 10.15252/emmm.202216289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 05/18/2022] [Indexed: 11/09/2022] Open
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Yoon B, Yeung P, Santistevan N, Bluhm LE, Kawasaki K, Kueper J, Dubielzig R, VanOudenhove J, Cotney J, Liao EC, Grinblat Y. Zebrafish models of alx-linked frontonasal dysplasia reveal a role for Alx1 and Alx3 in the anterior segment and vasculature of the developing eye. Biol Open 2022; 11:bio059189. [PMID: 35142342 PMCID: PMC9167625 DOI: 10.1242/bio.059189] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 01/28/2022] [Indexed: 11/18/2022] Open
Abstract
The cellular and genetic mechanisms that coordinate formation of facial sensory structures with surrounding skeletal and soft tissue elements remain poorly understood. Alx1, a homeobox transcription factor, is a key regulator of midfacial morphogenesis. ALX1 mutations in humans are linked to severe congenital anomalies of the facial skeleton (frontonasal dysplasia, FND) with malformation or absence of eyes and orbital contents (micro- and anophthalmia). Zebrafish with loss-of-function alx1 mutations develop with craniofacial and ocular defects of variable penetrance, likely due to compensatory upregulation in expression of a paralogous gene, alx3. Here we show that zebrafish alx1;alx3 mutants develop with highly penetrant cranial and ocular defects that resemble human ALX1-linked FND. alx1 and alx3 are expressed in anterior cranial neural crest (aCNC), which gives rise to the anterior neurocranium (ANC), anterior segment structures of the eye and vascular pericytes. Consistent with a functional requirement for alx genes in aCNC, alx1; alx3 mutants develop with nearly absent ANC and grossly aberrant hyaloid vasculature and ocular anterior segment, but normal retina. In vivo lineage labeling identified a requirement for alx1 and alx3 during aCNC migration, and transcriptomic analysis suggested oxidative stress response as a key target mechanism of this function. Oxidative stress is a hallmark of fetal alcohol toxicity, and we found increased penetrance of facial and ocular malformations in alx1 mutants exposed to ethanol, consistent with a protective role for alx1 against ethanol toxicity. Collectively, these data demonstrate a conserved role for zebrafish alx genes in controlling ocular and facial development, and a novel role in protecting these key midfacial structures from ethanol toxicity during embryogenesis. These data also reveal novel roles for alx genes in ocular anterior segment formation and vascular development and suggest that retinal deficits in alx mutants may be secondary to aberrant ocular vascularization and anterior segment defects. This study establishes robust zebrafish models for interrogating conserved genetic mechanisms that coordinate facial and ocular development, and for exploring gene--environment interactions relevant to fetal alcohol syndrome.
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Affiliation(s)
- Baul Yoon
- Departments of Integrative Biology and Neuroscience, University of Wisconsin, Madison, WI 53706, USA
- Genetics Ph.D. Training Program, University of Wisconsin, Madison, WI 53706, USA
| | - Pan Yeung
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, 02114, USA
| | - Nicholas Santistevan
- Departments of Integrative Biology and Neuroscience, University of Wisconsin, Madison, WI 53706, USA
- Genetics Ph.D. Training Program, University of Wisconsin, Madison, WI 53706, USA
| | - Lauren E. Bluhm
- Departments of Integrative Biology and Neuroscience, University of Wisconsin, Madison, WI 53706, USA
| | - Kenta Kawasaki
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, 02114, USA
| | - Janina Kueper
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, 02114, USA
- Institute of Human Genetics, University of Bonn, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Richard Dubielzig
- Comparative Ocular Pathology Laboratory of Wisconsin (COPLOW), University of Wisconsin, Madison, WI 53706, USA
| | - Jennifer VanOudenhove
- University of Connecticut School of Medicine, Department of Genetics and Genome Sciences, Farmington, CT 06030, USA
| | - Justin Cotney
- University of Connecticut School of Medicine, Department of Genetics and Genome Sciences, Farmington, CT 06030, USA
| | - Eric C. Liao
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, 02114, USA
| | - Yevgenya Grinblat
- Departments of Integrative Biology and Neuroscience, University of Wisconsin, Madison, WI 53706, USA
- Genetics Ph.D. Training Program, University of Wisconsin, Madison, WI 53706, USA
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3
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Pini J, Kueper J, Hu YD, Kawasaki K, Yeung P, Tsimbal C, Yoon B, Carmichael N, Maas RL, Cotney J, Grinblat Y, Liao EC. ALX1-related frontonasal dysplasia results from defective neural crest cell development and migration. EMBO Mol Med 2020; 12:e12013. [PMID: 32914578 PMCID: PMC7539331 DOI: 10.15252/emmm.202012013] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 08/12/2020] [Accepted: 08/13/2020] [Indexed: 01/02/2023] Open
Abstract
A pedigree of subjects presented with frontonasal dysplasia (FND). Genome sequencing and analysis identified a p.L165F missense variant in the homeodomain of the transcription factor ALX1 which was imputed to be pathogenic. Induced pluripotent stem cells (iPSC) were derived from the subjects and differentiated to neural crest cells (NCC). NCC derived from ALX1L165F/L165F iPSC were more sensitive to apoptosis, showed an elevated expression of several neural crest progenitor state markers, and exhibited impaired migration compared to wild-type controls. NCC migration was evaluated in vivo using lineage tracing in a zebrafish model, which revealed defective migration of the anterior NCC stream that contributes to the median portion of the anterior neurocranium, phenocopying the clinical presentation. Analysis of human NCC culture media revealed a change in the level of bone morphogenic proteins (BMP), with a low level of BMP2 and a high level of BMP9. Soluble BMP2 and BMP9 antagonist treatments were able to rescue the defective migration phenotype. Taken together, these results demonstrate a mechanistic requirement of ALX1 in NCC development and migration.
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Affiliation(s)
- Jonathan Pini
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
- Shriners Hospital for Children, Boston, MA, USA
| | - Janina Kueper
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
- Shriners Hospital for Children, Boston, MA, USA
- Life and Brain Center, University of Bonn, Bonn, Germany
| | - Yiyuan David Hu
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
- Shriners Hospital for Children, Boston, MA, USA
| | - Kenta Kawasaki
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
- Shriners Hospital for Children, Boston, MA, USA
| | - Pan Yeung
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
- Shriners Hospital for Children, Boston, MA, USA
| | - Casey Tsimbal
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
- Shriners Hospital for Children, Boston, MA, USA
| | - Baul Yoon
- Departments of Integrative Biology, Neuroscience, and Genetics Ph.D. Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Nikkola Carmichael
- Department of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Richard L Maas
- Department of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Justin Cotney
- Genetics and Genome Sciences, UConn Health, Farmington, CT, USA
| | - Yevgenya Grinblat
- Departments of Integrative Biology, Neuroscience, and Genetics Ph.D. Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Eric C Liao
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
- Shriners Hospital for Children, Boston, MA, USA
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Yeung P, Zhang W, Wang X, Yan C, Chan B. A human osteoarthritis osteochondral organ culture model for cartilage tissue engineering. Biomaterials 2018; 162:1-21. [DOI: 10.1016/j.biomaterials.2018.02.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 01/31/2018] [Accepted: 02/02/2018] [Indexed: 12/12/2022]
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Diao HJ, Fung HS, Yeung P, Lam K, Yan CH, Chan BP. Dynamic cyclic compression modulates the chondrogenic phenotype in human chondrocytes from late stage osteoarthritis. Biochem Biophys Res Commun 2017; 486:14-21. [DOI: 10.1016/j.bbrc.2017.02.073] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 02/13/2017] [Indexed: 11/24/2022]
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Tang AHL, Yeung P, Chan GCF, Chan BP, Wong KKY, Tsia KK. Time-stretch microscopy on a DVD for high-throughput imaging cell-based assay. Biomed Opt Express 2017; 8:640-652. [PMID: 28270973 PMCID: PMC5330545 DOI: 10.1364/boe.8.000640] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 12/21/2016] [Accepted: 12/25/2016] [Indexed: 06/06/2023]
Abstract
Cell-based assay based on time-stretch imaging is recognized to be well-suited for high-throughput phenotypic screening. However, this ultrafast imaging technique has primarily been limited to suspension-cell assay, leaving a wide range of solid-substrate assay formats uncharted. Moreover, time-stretch imaging is generally restricted to intrinsic biophysical phenotyping, but lacks the biomolecular signatures of the cells. To address these challenges, we develop a spinning time-stretch imaging assay platform based on the functionalized digital versatile disc (DVD). We demonstrate that adherent cell culture and biochemically-specific cell-capture can now be assayed with time-stretch microscopy, thanks to the high-speed DVD spinning motion that naturally enables on-the-fly cellular imaging at an ultrafast line-scan rate of >10MHz. As scanning the whole DVD at such a high speed enables ultra-large field-of-view imaging, it could be favorable for scaling both the assay throughput and content as demanded in many applications, e.g. drug discovery, and rare cancer cell screening.
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Affiliation(s)
- Anson H. L. Tang
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - P. Yeung
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Godfrey C. F. Chan
- Department of Paediatrics & Adolescent Medicine, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Barbara P. Chan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Kenneth K. Y. Wong
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Kevin K. Tsia
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong, China
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Vazirabadi G, Gavard J, Rockefeller NF, Nieto R, Marcu I, Miller C, Yeung P, Holloran-Schwartz MB, Steele A, Leong FC, McLennan MT, Campian EC. Correlation Between Frequency of Urinary Symptoms and Clinical and Image-Based Indexes of Interstitial Cystitis in a Prospective Cohort of Patients with and without Interstitial Cystitis. J Minim Invasive Gynecol 2016. [DOI: 10.1016/j.jmig.2016.08.048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Zhang C, O'Young G, Wikstrom K, Davison T, Yeung P, Cattaruzza F, Yen WC, Hoey T, Lewicki J, Rachmann R, Kerr P, Hill L, Eason R, McErlean S, Liu Y, Kapoun AM. Abstract P3-07-57: Development of a 6-gene qPCR RUO-validated assay as a predictive biomarker for response of vantictumab (OMP-18R5; anti-frizzled) in HER2- breast cancer patients. Cancer Res 2016. [DOI: 10.1158/1538-7445.sabcs15-p3-07-57] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: We have developed a monoclonal antibody, vantictumab that blocks canonical WNT/β-catenin signaling through binding of five FZD receptors (1, 2, 5, 7, 8). This antibody inhibits the growth of several tumor types, including breast. Vantictumab reduces tumor-initiating cell frequency and exhibits synergistic activity with standard-of-care (SOC) agents (Gurney et al, 2012). To target breast cancer patients most likely to respond to vantictumab, we undertook a predictive biomarker study.
Methods: We have identified a 6-gene Wnt pathway-related signature, FBXW2, CCND2, RHOU, CTBP2, WIF1, and DKK1, based on microarray gene expression data from 8 breast cancer patient derived xenograft (PDX) models with established in vivo response to vantictumab plus SOC. This signature successfully predicted the response of 8 additional and independent PDX breast tumors. We further developed a qPCR Research Use Only (RUO) assay for the 6 genes to be used on FFPE human breast tumor samples. Multiple assays targeting different regions spanning each mRNA transcript were tested and selected based on PCR efficiency, specificity and sensitivity. We compared assay sensitivity under different cDNA synthesis and pre-amplification conditions: random vs. gene-specific priming, number of pre-amplification cycles, pre-amplification reaction volumes, and cDNA synthesis kits. A repeatability study was performed to test assay performance. The pre-amplification and PCR were repeated over three separate days and across two independent labs.
Results: Our results showed that cDNA synthesis by gene-specific priming followed by 18 cycles of pre-amplification performed the best and the assay is robust with minimal starting FFPE RNA input. The results of the repeatability study were consistent among the different days and the different labs (<5% CV). Using the 6-gene qPCR RUO assay, the signature score from the microarray data was further refined using 12 PDX HER2- breast tumors with known in vivo response to vantictumab with SOC. The prevalence of the 6-gene signature was established using ∼100 HER2- breast cancer samples.
Conclusions: A robust 6-gene RUO-validated assay was developed as a predictive biomarker for vantictumab in HER2- breast cancer. The assay is currently being evaluated in a Phase 1b study of vantictumab with paclitaxel in HER2- breast cancer.
Citation Format: Zhang C, O'Young G, Wikstrom K, Davison T, Yeung P, Cattaruzza F, Yen W-C, Hoey T, Lewicki J, Rachmann R, Kerr P, Hill L, Eason R, McErlean S, Liu Y, Kapoun AM. Development of a 6-gene qPCR RUO-validated assay as a predictive biomarker for response of vantictumab (OMP-18R5; anti-frizzled) in HER2- breast cancer patients. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-07-57.
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Affiliation(s)
- C Zhang
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - G O'Young
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - K Wikstrom
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - T Davison
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - P Yeung
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - F Cattaruzza
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - W-C Yen
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - T Hoey
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - J Lewicki
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - R Rachmann
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - P Kerr
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - L Hill
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - R Eason
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - S McErlean
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - Y Liu
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
| | - AM Kapoun
- OncoMed Pharmaceuticals Inc., Redwood City, CA; Almac Group LTD, Craigavon, United Kingdom
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Yeung P, Sin HS, Chan S, Chan GCF, Chan BP. Microencapsulation of Neuroblastoma Cells and Mesenchymal Stromal Cells in Collagen Microspheres: A 3D Model for Cancer Cell Niche Study. PLoS One 2015; 10:e0144139. [PMID: 26657086 PMCID: PMC4682120 DOI: 10.1371/journal.pone.0144139] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 11/14/2015] [Indexed: 12/18/2022] Open
Abstract
There is a growing trend for researchers to use in vitro 3D models in cancer studies, as they can better recapitulate the complex in vivo situation. And the fact that the progression and development of tumor are closely associated to its stromal microenvironment has been increasingly recognized. The establishment of such tumor supportive niche is vital in understanding tumor progress and metastasis. The mesenchymal origin of many cells residing in the cancer niche provides the rationale to include MSCs in mimicking the niche in neuroblastoma. Here we co-encapsulate and co-culture NBCs and MSCs in a 3D in vitro model and investigate the morphology, growth kinetics and matrix remodeling in the reconstituted stromal environment. Results showed that the incorporation of MSCs in the model lead to accelerated growth of cancer cells as well as recapitulation of at least partially the tumor microenvironment in vivo. The current study therefore demonstrates the feasibility for the collagen microsphere to act as a 3D in vitro cancer model for various topics in cancer studies.
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Affiliation(s)
- Pan Yeung
- Tissue Engineering Laboratory, Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region, China
| | - Hoi Shun Sin
- Tissue Engineering Laboratory, Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region, China
| | - Shing Chan
- Department of Adolescence Medicine and Paediatrics, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Godfrey Chi Fung Chan
- Department of Adolescence Medicine and Paediatrics, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Barbara Pui Chan
- Tissue Engineering Laboratory, Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region, China
- * E-mail:
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Yeung P, Gusovsky O, Agnelli R, Peavey M, Tu F, Bajzak K, Lamvu G, Winer W, Albee R, Sinervo K. A Multi-Center Study of Patients After Excision of Endometriosis: Do We Need Another Randomized Comparative Trial of Excision Versus Ablation? J Minim Invasive Gynecol 2012. [DOI: 10.1016/j.jmig.2012.08.786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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11
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Yeung P, Bolden C, Westreich D, Sobolewski C. Patient Preferences of Cosmesis for Abdominal Incisions in Gynecologic Surgery. J Minim Invasive Gynecol 2012. [DOI: 10.1016/j.jmig.2012.08.792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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12
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Gerson LB, Mitra S, Bleker WF, Yeung P. Control of intra-oesophageal pH in patients with Barrett's oesophagus on omeprazole-sodium bicarbonate therapy. Aliment Pharmacol Ther 2012; 35:803-9. [PMID: 22356659 DOI: 10.1111/j.1365-2036.2012.05016.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 11/08/2011] [Accepted: 01/17/2012] [Indexed: 12/27/2022]
Abstract
BACKGROUND Approximately 30-40% of patients with Barrett's oesophagus (BE) patients manifest abnormal oesophageal pH profiles despite proton pump inhibitor (PPI) therapy. AIM To determine control of oesophageal reflux using Bravo pH monitoring in patients BE on omeprazole-sodium bicarbonate oral suspension powder (Ome-NaBic) 40 mg twice daily. METHODS Initial pH monitoring off PPI for 1 week was performed. All patients underwent repeat pH testing on Ome-NaBic administered before breakfast and at bedtime after 21-28 days of therapy depending upon the prior PPI therapy. The goal was to enroll 30 subjects, however, the trial was terminated prematurely when the sponsor lost financing due to a change in business strategy. RESULTS A total of 88 patients responded to the study invitation, 27 patients signed informed consent, and 21 patients underwent pH testing of PPI. A total of 15 patients completed the protocol (13 men, 2 women). Demographic information for patients completing at least one Bravo study included a mean (±s.d.) age 62 ± 9 years; body mass index 31 ± 8 kg/m(2) (range 23-48); mean BE length of 2.6 ± 2 cm; 9 (43%) patients with long segment BE. All (100%) patients demonstrated normalisation of supine pH on both days of Ome-NaBic therapy. One patient (6%) demonstrated abnormal upright reflux on the second day of monitoring on Ome-NaBic therapy; all the other patients demonstrated normal pH scores on therapy. CONCLUSIONS Administration of twice daily Ome-NaBic demonstrated control of nocturnal oesophageal reflux in 100% of patients with Barrett's oesophagus, and complete control of oesophageal pH during 97% of the 24-h recording periods.
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Affiliation(s)
- L B Gerson
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, CA, USA.
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Yen WC, Fischer M, Beviglia L, Yeung P, Kapoun A, Wang M, Lewicki J, Gurney A, Hoey T. Abstract P6-15-10: Targeting Delta-Like 4 Ligand (DLL4)/Notch Signaling by a Novel Anti-DLL4 Antibody Inhibits Tumor Growth through Altering Cancer Stem Cell and Epithelial-to-Mesenchymal Transition-Associated Genes in Triple Negative Breast Cancer. Cancer Res 2010. [DOI: 10.1158/0008-5472.sabcs10-p6-15-10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Triple negative breast cancer (TNBC, ER-, PR-Her2-) accounts for 10% of all types of breast cancer and is known to be particularly aggressive and refractory to current therapies. Chemotherapeutic agents, such as taxanes, are currently the only treatment option for this type of breast cancer. However, these treatments often result in local and systemic relapse. While several promising targeted agents have improved the relapse rate in the combination with chemotherapy in patients with pathologic complete response, those who do not achieve pathologic complete response still have a poor prognosis. We previously demonstrated that interfering with Deltalike 4 ligand (DLL4)/Notch signaling by an anti-DLL4 antibody decreased tumor growth and delayed tumor recurrence following paclitaxel treatment through reducing breast cancer stem cell fraction and tumorigenicity (Proc Am Asso Cancer Res. 51:4, 2010). CD44+/CD24low cells have been demonstrated to be highly tumorigenic in breast tumors and are associated with treatment resistance (PNAS U S A, 106: 13820-13825, 2009). To gain insights into the mechanism of action of anti-DLL4-mediated TNBC growth inhibition, we evaluated the effect of anti-DLL4 on breast cancer CD44+/CD24low the expression patterns of a list of genes involved in sternness, differentiation, and key stem cell signaling pathways in TNBC xenograft tumors following paclitaxel with and without antibody treatment in vivo. Our data showed that paclitaxel treatment resulted in significant changes of gene expression patterns in the CD44+/CD24low cells in the residual tumors. We further analyzed these genes and identified several genes related to Notch signaling, stem cell maintenance and epithelial-to-mesenchymal transition that were modulated differentially by treatment with paclitaxel and/or anti-DLL4. In a metastatic TNBC orthotopic tumor model, the anti-DLL4 treatment resulted in tumor growth inhibition at the primary site and distant organs. Taken together, our findings suggest that targeting DLL4 may improve the efficacy of current treatments, delay tumor recurrence, and reduce metastatic growth in TNBC.
Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-15-10.
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Affiliation(s)
- W-C Yen
- OncoMed.Pharmaceuticals, Inc., Redwood City, CA; OncoMed Pharmaceuticals, Inc., Redwood City, CA
| | - M Fischer
- OncoMed.Pharmaceuticals, Inc., Redwood City, CA; OncoMed Pharmaceuticals, Inc., Redwood City, CA
| | - L Beviglia
- OncoMed.Pharmaceuticals, Inc., Redwood City, CA; OncoMed Pharmaceuticals, Inc., Redwood City, CA
| | - P Yeung
- OncoMed.Pharmaceuticals, Inc., Redwood City, CA; OncoMed Pharmaceuticals, Inc., Redwood City, CA
| | - A Kapoun
- OncoMed.Pharmaceuticals, Inc., Redwood City, CA; OncoMed Pharmaceuticals, Inc., Redwood City, CA
| | - M Wang
- OncoMed.Pharmaceuticals, Inc., Redwood City, CA; OncoMed Pharmaceuticals, Inc., Redwood City, CA
| | - J Lewicki
- OncoMed.Pharmaceuticals, Inc., Redwood City, CA; OncoMed Pharmaceuticals, Inc., Redwood City, CA
| | - A Gurney
- OncoMed.Pharmaceuticals, Inc., Redwood City, CA; OncoMed Pharmaceuticals, Inc., Redwood City, CA
| | - T. Hoey
- OncoMed.Pharmaceuticals, Inc., Redwood City, CA; OncoMed Pharmaceuticals, Inc., Redwood City, CA
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Allen SC, Charlton C, Backen W, Warwick-Sanders M, Yeung P. Performing slow vital capacity in older people with and without cognitive impairment--is it useful? Age Ageing 2010; 39:588-91. [PMID: 20625184 DOI: 10.1093/ageing/afq084] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND most patients with moderate cognitive impairment are unable to perform forced spirometry. It has been suggested that slow vital capacity (SVC) is easier to perform than forced vital capacity (FVC) because it requires less understanding and co-ordination. We conducted a study to determine whether that assertion is correct. METHODS we studied 83 inpatients, mean age 83 years (range 67-95, 51 female). They had measurements made of FVC, SVC and the Mini-Mental State Examination (MMSE). The spirometry was conducted using the European Respiratory Society/American Thoracic Society standards. RESULTS of the 83 subjects, 38 were able to do both FVC and SVC and 32 were unable to do either. The overall concordance was 84%. Twelve were able to do SVC but not FVC (eight due to excessive cough, two due to weakness and two had an MMSE < 24 with poor co-ordination). An inability to do neither FVC nor SVC was predicted by an MMSE < 24/30 (P < 0.0001) with a sensitivity of 88% and specificity of 67%. CONCLUSION SVC is not a usable substitute for FVC for elderly patients with cognitive impairment but is of some utility for those who tend to cough. An MMSE < 24/30 is predictive of inability to perform FVC and SVC.
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Affiliation(s)
- S C Allen
- Department of Medicine and Geriatrics, The Royal Bournemouth Hospital, Dorset, UK.
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Allen S, Yeung P, Janczewski M, Siddique N. Predicting inadequate spirometry technique and the use of FEV1/FEV3 as an alternative to FEV1/FVC for patients with mild cognitive impairment. The Clinical Respiratory Journal 2008; 2:208-13. [DOI: 10.1111/j.1752-699x.2008.00063.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Abstract
BACKGROUND Idiopathic sudden sensorineural hearing loss (ISSHL) with or without tinnitus is common and presents a health problem with significant effect on quality of life. Hyperbaric oxygen therapy (HBOT) may improve oxygen supply to the inner ear and, it is postulated, may result in an improvement in hearing and/or a reduction in the intensity of tinnitus. OBJECTIVES To assess the benefits and harms of HBOT for treating ISSHL and/or tinnitus. SEARCH STRATEGY We initially searched in June 2004 and repeated the search in June 2006. Our search included the Cochrane Ear, Nose and Throat Disorders Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2 2006), MEDLINE (1951 to 2006), EMBASE (1974 to 2006), CINAHL, Database of Randomised Trials in Hyperbaric Medicine (DORCTHIM), AMED, LILACS, KOREAMED, INDMED, National Research Register (NRR), CSA, ISI PROCEEDINGS and ZETOC. SELECTION CRITERIA Randomised studies comparing the effect on ISSHL and/or tinnitus of therapeutic regimens which include HBOT with those that exclude HBOT. DATA COLLECTION AND ANALYSIS Three authors independently evaluated the quality of the relevant trials using the validated Oxford-Scale (Jadad 1996) and extracted the data from the included trials. MAIN RESULTS Six trials contributed to this review (308 subjects). Pooled data from two trials involving 114 patients did not show any significant improvement in the chance of a 50% increase in hearing threshold on Pure Tone Average (PTA) when HBOT was used (relative risk [RR] with HBOT 1.53, 95% CI 0.85 to 2.78, P = 0.16), but did show a significantly increased chance of a 25% increase in PTA (RR 1.39, 95% CI 1.05 to 1.84, P = 0.02). There was a 22% greater chance of improvement with HBOT, and the number needed to treat (NNT) to achieve one extra good outcome was five (95% CI 3 to 20). A single trial involving 50 subjects also suggested significantly more improvement in the mean PTA threshold with HBOT, expressed as a percentage of baseline (WMD 37%, 95% CI 22% to 53%, P < 0.001). The significance of any improvement following HBOT in a subjective rating of tinnitus could not be assessed due to poor reporting. There were no significant improvements in hearing or tinnitus reported in the single study to examine chronic presentation (six months) of ISSHL and/or tinnitus. AUTHORS' CONCLUSIONS For people with early presentation of ISSHL, the application of HBOT significantly improved hearing loss, but the clinical significance of the level of improvement is not clear. We could not assess the effect of HBOT on tinnitus by pooled data analysis. The routine application of HBOT to these patients cannot be justified from this review. In view of the modest number of patients, methodological shortcomings and poor reporting, this result should be interpreted cautiously, and an appropriately powered trial of high methodological rigour is justified to define those patients (if any) who can be expected to derive most benefit from HBOT. There is no evidence of a beneficial effect of HBOT on chronic presentation of ISSHL and/or tinnitus and we do not recommend use of HBOT for this purpose based on the single study available.
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Affiliation(s)
- M H Bennett
- Prince of Wales Hospital, Diving and Hyperbaric Medicine, Barker Street, Randwick, NSW, Australia, 2031.
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Allen SC, Yeung P. Inability to draw intersecting pentagons as a predictor of unsatisfactory spirometry technique in elderly hospital inpatients. Age Ageing 2006; 35:304-6. [PMID: 16638772 DOI: 10.1093/ageing/afj090] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Stephen C Allen
- Department of Medicine and Geriatrics, The Royal Bournemouth Hospital, Bournemouth, Dorset, UK.
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Bennett M, Kertesz T, Yeung P. Hyperbaric oxygen therapy for idiopathic sudden sensorineural hearing loss and tinnitus: a systematic review of randomized controlled trials. J Laryngol Otol 2006; 119:791-8. [PMID: 16259656 DOI: 10.1258/002221505774481246] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Background: Idiopathic sudden sensorineural hearing loss (ISSHL) and tinnitus are common. Hyperbaric oxygen therapy (HBOT) may improve hearing loss and/or reduce the intensity of tinnitus.Methods: We performed a systematic search of the literature for randomized controlled trials, and made pooled analyses of pre-determined clinical outcomes where possible.Results: Six trials contributed to this review (304 subjects). Pooled analysis suggested a significantly increased chance of a 25 per cent improvement in hearing threshold on pure tone average with HBOT (relative risk (RR) 1.39, 95 per cent confidence interval (CI) 1.05–1.84, p = 0.02; number-needed-to-treat 5, 95 per cent CI 3–20), but not a 50 per cent increase (RR 1.53, 95 per cent CI 0.85–2.78, p = 0.16). The significance of any improvement in tinnitus following HBOT could not be assessed due to poor reporting.Conclusions: HBOT improved hearing, but the clinical significance of the level of improvement is not clear. Routine application of HBOT to patients with ISSHL is not justified by this review. More research is needed.
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Affiliation(s)
- M Bennett
- Department of Diving and Hyperbaric Medicine, Prince of Wales Hospital and University of NSW, Australia.
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Abstract
BACKGROUND Idiopathic sudden sensorineural hearing loss (ISSHL) with or without tinnitus is common and presents a health problem with significant effect on quality of life. Hyperbaric oxygen therapy (HBOT) may improve oxygen supply to the inner ear and thereby result in an improvement in hearing and/or a reduction in the intensity of tinnitus. OBJECTIVES To assess the benefits and harms of HBOT for treating ISSHL and tinnitus. SEARCH STRATEGY We searched the Cochrane ENT Specialist Register (June 2004), CENTRAL (The Cochrane Library Issue 3, 2004), MEDLINE (1966 to 2004), EMBASE (1974 to 2004), CINAHL (1982 to 2004), DORCTHIM (1996 to 2004), and reference lists of articles. Researchers in the field were contacted. SELECTION CRITERIA Randomised studies comparing the effect on ISSHL and/or tinnitus of therapeutic regimens which include HBOT with those that exclude HBOT. DATA COLLECTION AND ANALYSIS Three reviewers independently evaluated the quality of the relevant trials using the validated Jadad 1996 Oxford-Scale and extracted the data from the included trials. MAIN RESULTS Five trials contributed to this review (254 subjects, 133 receiving HBOT and 120 control). Pooled data from two trials involving 114 patients (45% of the total) suggested there was a trend towards, but no significant increase in, the chance of a 50% increase in hearing threshold on Pure Tone Average (PTA) over four frequencies when HBOT was used (relative risk (RR) for good outcome with HBOT 1.53, 95% confidence interval (CI) 0.85 to 2.78, P = 0.16). The chance of achieving a 25% increase with HBOT was, however, statistically significant (RR 1.39, 95% CI 1.05 to 1.84, P = 0.02). Fifty-six per cent of the control subjects achieved this outcome versus 78% of the HBOT subjects, with the number-needed-to-treat (NNT) to achieve one extra good outcome being 5 (95% CI 3 to 20). A single trial involving 50 subjects (20% of the total) also suggested a significant improvement in the mean PTA threshold expressed as a percentage of baseline (61% improvement with HBOT, 24% with control, WMD 37%, 95% CI 22% to 53%). The effect of HBOT in tinnitus could not be assessed due to poor reporting. There were no significant improvements in hearing or tinnitus reported in the single study to examine the effect of HBOT on a chronic presentation (six months) of ISSHL and/or tinnitus. AUTHORS' CONCLUSIONS For people with early presentation of ISSHL, the application of HBOT significantly improved hearing loss, but the clinical significance of the level of improvement is not clear. We could not assess the effect of HBOT on tinnitus by pooled analysis. The routine application of HBOT to these patients cannot be justified from this review. In view of the modest number of patients, methodological shortcomings and poor reporting, this result should be interpreted cautiously, and an appropriately powered trial of high methodological rigour is justified to define those patients (if any) who can be expected to derive most benefit from HBOT. There is no evidence of a beneficial effect of HBOT on chronic presentation of ISSHL and/or tinnitus.
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Affiliation(s)
- M H Bennett
- Diving and Hyperbaric Medicine, Prince of Wales Hospital, Barker St., Randwick, NSW, Australia, 2031.
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Abstract
BACKGROUND Malignancies of the external auditory canal and temporal bone are uncommon. A retrospective review was conducted of a large series treated at the Prince of Wales hospital between 1974 and 1995. METHODS Retrospective review of 59 cases of ear canal and temporal bone malignancies. These were analysed according to histopathology, disease extent, surgery, margin status and survival. A TNM-type staging system was applied to 51 cases and Kaplan-Meier survival analysis applied to this group. RESULTS The 5-year cancer-specific survival (CSS) for the series was 54%. For stages 1, 2, 3 and 4 disease, the CSS were 90, 45, 40 and 19%, respectively. Survival was significantly higher where clear surgical margins were achieved (80 vs 35%). CONCLUSIONS Carcinoma of the external ear canal is rare and, in Australia, is often related to recurrence of periauricular cutaneous malignancy. Surgical extirpation with clear margins provides the best survival.
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Affiliation(s)
- P Yeung
- Department of Otolaryngology Head and Neck Surgery, Prince of Wales Hospital, Randwick, New South Wales, Australia
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Abstract
Australia has one of the highest national incidences of mesothelioma in the world and the rate is still rising. An industry-occupation matrix analysis was conducted for the 858 mesothelioma cases that were reported to the Australian Mesothelioma Surveillance Program between 1980 and 1985. Definite, probable, or possible occupational exposure had occurred in 57 percent (492/858) of the subjects. The primary asbestos production or manufacturing industry constituted the largest number of cases (137/492, 27.8%), followed by shipbuilding, repair and demolition (114/492, 23.2%), the building industry (69/492, 14.1%), and the railway locomotive construction and maintenance industry (47/492, 9.6%). Laborers constituted 14.8 percent (n = 73) of the occupations with a history of exposure to asbestos, followed by carpenters (13.0%, n = 64), boilermakers (10.6%, n = 52), and fitters/turners (8.1%, n = 40). The distribution of occupations in specific industries is presented in this article.
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Affiliation(s)
- P Yeung
- Pacific OHS Pty Ltd, Sydney, Australia
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Yeung P, Rogers A, Johnson A. Distribution of mesothelioma cases in different occupational groups and industries in Australia, 1979-1995. Appl Occup Environ Hyg 1999; 14:759-67. [PMID: 10590549 DOI: 10.1080/104732299302189] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Australia was a producer and user of asbestos and has one of the highest national incidences of mesothelioma in the world. The incidence is still rising and expected to do so for another 10-20 years. A study was conducted in 1996 to examine the past and current incidence rates of mesothelioma in a number of industries and occupations as the basis for predicting future outcomes. Occupational histories of a total of 3758 mesothelioma cases collected by two sequential national schemes--the Australian Mesothelioma Surveillance Program (1979-1985) and Australian Mesothelioma Register (1986-1995)--were reviewed and coded by the authors. The building industry contributed the largest number of cases nationwide followed by shipbuilding and repair, asbestos cement production, crocidolite mining and milling, railway locomotive construction and repair, coal-fired power stations, and other engineering operations. The mean latency between initial occupational asbestos exposure and diagnosis of the disease was 37.4 years (range = 4-66 years) for cases notified between 1979 and 1985, and 41.4 years (range = 6-84 years) for those between 1986 and 1995. Trends for each industry group have been changing considerably in the past 16 years, with the traditional primary asbestos industry cases from crocidolite mining and milling now on the decline and cases from asbestos cement production having plateaued. In contrast, more recently, more cases were observed from the asbestos user industries such as the building industry, and from occupations such as plumbers, carpenters, machinists, and car mechanics. These increases might be a reflection of the longer latency effects of the intermittent and less severe exposures in these larger occupational groups.
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Affiliation(s)
- P Yeung
- Alan Rogers OH&S Pty Ltd, Clovelly, Australia
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Abstract
BACKGROUND Indirect laryngoscopy (IDL) is often performed prior to thyroid surgery to detect pre-existing vocal cord pathology. METHODS A retrospective chart review of 201 patients undergoing thyroid surgery at the Prince of Wales Hospital was undertaken in order to study the patterns of pre-operative and postoperative voice changes and IDL findings. RESULTS A total of 9% of patients had pre-operative voice symptoms, and 22% of this group had abnormalities detected on pre-operative IDL. Of 160 documented IDL, 4% revealed vocal cord pathology in asymptomatic patients, including an asymptomatic recurrent laryngeal nerve palsy. CONCLUSIONS Indirect laryngoscopy remains a useful but flawed pre-operative screening tool for patients with voice symptoms, but the literature suggests that more advanced phoniatric tests will provide superior diagnostic sensitivity. The role of routine pre-operative laryngoscopy for asymptomatic patients is of debatable value.
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Affiliation(s)
- P Yeung
- Prince of Wales Hospital, Sydney, New South Wales, Australia
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Abstract
OBJECTIVE To assess the intratubal pressure (ITP) and patency status of the fallopian tubes before and after transcervical catheterization of the fallopian tubes (TCFT). DESIGN Prospective procedural assessment. SETTING Pope Paul VI Institute for the Study of Human Reproduction. PATIENT(S) Two hundred thirty-four women with either primary or secondary infertility. INTERVENTION(S) Patients underwent selective hysterosalpingography and, in some cases, TCFT with measurement of the ITP before and after the procedure. MAIN OUTCOME MEASURE(S) The ITP before and after TCFT. RESULT(S) The mean (+/-SD) ITP in freely patent tubes was 0.53 +/- 0.06 atm, that in partially obstructed tubes was 1.23 +/- 0.52 atm, and that in completely obstructed tubes was 2.79 +/- 1.40 atm. After TCFT, the mean (+/-SD) ITP in partially obstructed tubes decreased to 0.64 +/- 0.31 atm and that in completely obstructed tubes decreased to 1.86 +/- 1.35 atm. The ITP was normalized in 76% of partially obstructed tubes and in 29.5% of completely obstructed tubes. In all cases of complete obstruction in which surgical correction was attempted, organic pathology was identified. CONCLUSION(S) The procedure described is a safe and easy means of obtaining reliable and significant information on the status of the proximal fallopian tube.
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Affiliation(s)
- T W Hilgers
- Pope Paul VI Institute for the Study of Human Reproduction, Omaha, Nebraska 68106, USA
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Yeung P, Patience K, Apthorpe L, Willcocks D. An Australian study to evaluate worker exposure to chrysotile in the automotive service industry. Appl Occup Environ Hyg 1999; 14:448-57. [PMID: 10461401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
A study was conducted in Sydney, Australia, in 1996 to investigate the current exposure levels, control technologies, and work practices in five service garages (four car and one bus), three brake bonding workshops, and one gasket processing workshop. This study formed part of the assessment of chrysotile as a priority existing chemical under the Australian National Industrial Chemicals Notification and Assessment Scheme. A total of 68 (11 personal and 57 area) air samples were collected, in accordance with the Australian standard membrane filter method. Fiber concentrations were determined by the traditional phase contrast microscopy (PCM) method and 16 selected samples were analyzed by the more powerful transmission electron microscopy (TEM). Chrysotile exposure of car mechanics measured by PCM was typically below the reportable detection limit of 0.05 f/mL, irrespective of whether disc brake, drum brake, or clutch was being serviced. These low levels can be attributed to the wet cleaning or aerosol spray methods used in recent years to replace the traditional compressed air jet cleaning. In the three brake shoe relining workshops, task-specific exposure reached up to 0.16 f/mL in the processes of cutting and radius grinding. TEM results were generally higher, due to its higher resolution power. The median diameter on samples taken from the service garages (passenger cars), as determined by TEM, was 0.5-1.0 micron; and was between 0.2-0.5 micron for the brake bonding and gasket processing workshops, while that for the bus service depot was 0.1-0.2 micron. Most of the respirable fibers (84%, mainly forsterite) from the bus service depot were below 0.2 micron in diameter which is the resolution limit of PCM. In the brake bonding and gasket cutting workshops, 34 percent and 44 percent of the chrysotile fibers were below 0.2 micron in diameter.
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Affiliation(s)
- P Yeung
- Worksafe Australia, Sydney, Australia
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Yeung P, Crowe P, Bennett M. BAROGENIC RUPTURE OF THE STOMACH—A CASE FOR NON-OPERATIVE MANAGEMENT: REPLY. ANZ J Surg 1998. [DOI: 10.1111/j.1445-2197.1998.tb04684.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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LaGrow S, Leung JP, Leung S, Yeung P. The Effects on Visually Impaired Children of Viewing Fluorescent Stimuli under Black-Light Conditions. Journal of Visual Impairment & Blindness 1998. [DOI: 10.1177/0145482x9809200509] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this study, 30 children with low vision (divided into a high and a low visual acuity group) were presented with stimuli under four conditions (white stimuli-white light, orange stimuli-white light, white stimuli-black light, and orange stimuli-black light) and were asked to rank their preferences for the four conditions. The goal was to determine the effects of the various combinations of stimuli and lighting on the children's visual performance. The orange stimuli viewed under black light resulted in the best performance overall, benefited the low-acuity group more than the high-acuity group, and was the most-preferred condition for both groups.
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Affiliation(s)
- S.J. LaGrow
- School of Health Science, Massey University, Palmerston North, New Zealand
| | - J-P Leung
- Psychology Department, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
| | - S. Leung
- Ebenezer School and Home for the Visually Impaired, 131 Pokfulam Road, Hong Kong, China
| | - P. Yeung
- Ebenezer School and Home for the Visually Impaired
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Abstract
BACKGROUND The gene Nm23 is thought to play a role in the suppression of tumour metastasis. Reduced expression of Nm23 is seen in a number of human cancers, and is associated with increased metastasis and reduced survival, most strongly in ductal breast and colorectal carcinomas. METHODS Nm23 gene expression was compared in gastric carcinoma and normal gastric mucosa. Twenty-three gastric carcinomas were graded for differentiation as either well, moderately or poorly differentiated. Metastatic deposits from seven of the cases were also examined, along with 10 samples of normal gastric mucosa. Specimens were incubated with a murine monoclonal antibody against the protein product of Nm23, and examined by immunohistochemical staining. A semiquantitative immunostaining index was used. RESULTS All normal mucosa showed moderate to strong staining; 8 of 15 poorly differentiated carcinomas showed absent or weak staining; 1 of 6 moderately differentiated carcinomas stained weakly. Both well-differentiated carcinomas stained strongly; 1 of 7 metastatic deposits stained weakly. The difference in Nm23 expression between normal mucosa and carcinomas was statistically significant (P=0.024). However, there was no statistically significant difference between the three grades of carcinomas (P=0.51), or between primary and metastatic tumour (P=0.25, all by Chi-squared test). CONCLUSIONS These results suggest that Nm23 may have a role in gastric carcinoma pathogenesis, but do not show a correlation with metastasis. A larger study, involving detailed clinical staging and follow-up, may be of benefit.
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Affiliation(s)
- P Yeung
- Department of Surgery, Sutherland Hospital, Caringbah, New South Wales, Australia
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Affiliation(s)
- P Yeung
- Department of Surgery, Prince of Wales Hospital, Sydney, New South Wales, Australia
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Driscoll T, Mandryk J, Corvalan C, Nurminen M, Hull B, Rogers A, Yeung P, Hollo C, Ruck E, Leigh J. Health status and exposure of workers at a pilot brown coal liquefaction plant in Australia, 1985-1991. Occup Med (Lond) 1995; 45:239-46. [PMID: 7579298 DOI: 10.1093/occmed/45.5.239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
In 1985, Brown Coal Liquefaction (Victoria) Pty Ltd (BCLV) commenced operation of a pilot plant that investigated the feasibility of producing oil from brown coal. The plant operated for five years. This study aimed to use exposure and health information routinely collected by the company to characterize various health parameters of the workforce and to investigate whether any adverse health measures were exposure-related. About 1680 persons were employed at some time or other by BCLV, and the primary study population consisted of 408 workers who had a medical examination at the end of employment and who consented to being in an epidemiological study. Reported photosensitivity was associated with higher cumulative skin exposure (RR = 1.85; 95% CI = 1.22-2.78), with an exposure-response relationship of increasing risk with increasing skin exposure being suggested. There was no consistent evidence that chemical exposure at BCLV had any negative effect on the haematological, biochemical, endocrine or lung function of workers at the plant. However, the maximum follow-up period of less than eight years limits the ability of the study to detect any emerging chronic effects.
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Affiliation(s)
- T Driscoll
- National Institute of Occupational Health and Safety, Sydney, Australia
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Yanagawa N, Nissenson RA, Edwards B, Yeung P, Trizna W, Fine LG. Functional profile of the isolated uremic nephron: intrinsic adaptation of phosphate transport in the rabbit proximal tubule. Kidney Int 1983; 23:674-83. [PMID: 6876563 DOI: 10.1038/ki.1983.78] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The maintenance of phosphate homeostasis in uremia appears to be governed both by parathyroid hormone (PTH) and by PTH-independent adaptations in renal tubular function. The relative contributions of these two mechanisms that control phosphate excretion by the diseased kidney have been difficult to define in intact animals. The present study was designed to examine the nature of the adaptation of phosphate handling by the proximal tubule of subtotally nephrectomized, uremic rabbits in vitro. Euparathyroid and hyperparathyroid uremic rabbits were studied. Tubular sensitivity to PTH was examined in vitro. The dose-response relationship between bath PTH concentration and inhibition of lumen-to-bath phosphate flux (Jp-lb) in isolated perfused proximal straight tubules (PSTs) revealed that PTH sensitivity was increased in the euparathyroid uremic rabbits and was decreased in hyperparathyroid uremic rabbits. The dose-response to dibutyryl cAMP was the same as normal in both uremic groups. These data strongly suggest the existence of a receptor-mediated adaptation in the effects of PTH on the uremic proximal tubule. In addition to an altered PTH-sensitivity the uremic PST also exhibited an alteration in the basal rate of phosphate transport studied in the presence of normal rabbit serum. Although net volume flux across the PST increased in both uremic groups as a possible consequence of hypertrophy, net phosphate flux per unit length was unchanged. Considering the increase of luminal area in these tubules, net phosphate flux per unit reabsorptive surface area was actually decreased. This dissociation is supportive of the existence of an intrinsic tubular adaptation which is independent of the size of the tubule per se. These studies indicate that there is an intrinsic adaptation of the basal rate of phosphate transport by the uremic rabbit proximal tubule and that the sensitivity of the tubule to PTH is altered. The data are strongly suggestive of an increase in the number of PTH receptors in the proximal tubule of the euparathyroid uremic rabbit and suggest that "down regulation" or persistent occupancy of these receptors occurs when hyperparathyroidism supervenes.
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Yanagawa N, Yeung P, Trizna W, Fine LG. Regulation of phosphate excretion by the diseased kidney: the intrinsic proximal tubular adaptation. Adv Exp Med Biol 1982; 151:177-83. [PMID: 6295089 DOI: 10.1007/978-1-4684-4259-5_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Abstract
1 A new sensitive and rapid radioimmunoassay procedure for the determination of the plasma concentrations of the neuroleptic drug trifluoperazine is described. 2 The antiserum developed for trifluoperazine cross-reacted with N-desmethyltrifluoperazine and 7-hydroxytrifluoperazine to the extent of 26 and 24% respectively but its cross-reactivity with commonly co-administered tricyclic antidepressants and antianxiety agents tested was negligible. 3 The assay, based on the above antiserum, enabled the quantitation of 50 pg of the drug in 200 microliters of plasma with a coefficient of variation of about 2% and therefore should be applicable for singly dose pharmacokinetic and bioavailability studies. It should be applicable to therapeutic monitoring of the drug in patients.
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