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Pan DR, Juhlin E, Tran AN, Wei Q, Tang S, Bui AT, Iyer NG, Lee WT. A Southeast Asian collaborative Delphi consensus on surveying risk factors for head and neck cancer screening and prevention. Glob Surg 2022; 8:243. [PMID: 36561123 PMCID: PMC9770631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The objective of this study was to determine high value questions for early detection and prevention of head and neck cancer by querying content experts on patient risk factors relevant to local communities in Southeast Asia (i.e., Vietnam, Laos, China, and Singapore). The Delphi method was employed using three rounds of asynchronous surveying which included participants among five different collaborating medical centers. 60 total survey items were assessed for consensus defined by a priori measures on the relative level of value of these questions for use in head and neck cancer screening. 77% of items reached a consensus and no items were concluded to be of low value despite differences in conclusions regarding relative importance. Survey items focused on patient demographic information and physical examination were examined across variables such as expert department affiliation, academic designation, and years of experience and found to be without statistically significant differences. However, with consensus items related to social risk factors, it was determined that participants who had 15 or more years of experience or identified as otolaryngologists rated these items at a relatively lower value than their peers with less experience (p < 0.0001, p = 0.0017) or outside the field of otolaryngology (p = 0.0101). This study explicitly identifies patient variables to consider in head and neck cancer screening that have not previously been comprehensively or methodically assessed in current literature. Increasing awareness of these risk factors may benefit the design and implementation of future head and neck cancer early detection and prevention programs in Southeast Asia and beyond as well as positively impact head and neck cancer outcomes.
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Affiliation(s)
- DR Pan
- Department of Head and Neck Surgery & Communication Sciences, Duke University, Durham, North Carolina, United States of America
| | - E Juhlin
- Department of Head and Neck Surgery & Communication Sciences, Duke University, Durham, North Carolina, United States of America
| | - AN Tran
- Department of Family Medicine and Community Health, Duke University, Durham, North Carolina, United States of America
| | - Q Wei
- Department of Population Health Science, Duke University, Durham, North Carolina, United States of America,Department of Medicine, Duke University, Durham, North Carolina, United States of America
| | - S Tang
- Department of Population Health Science, Duke University, Durham, North Carolina, United States of America,Department of Medicine, Duke University, Durham, North Carolina, United States of America,Duke Global Health Institute, Duke University, Durham, North Carolina, United States of America
| | - AT Bui
- National Otolaryngology Hospital of Vietnam, Hanoi, Vietnam
| | - NG Iyer
- Department of Head and Neck Surgery, National Cancer Centre Singapore Duke-NUS Medical School, Singapore
| | - WT Lee
- Department of Head and Neck Surgery & Communication Sciences, Duke University, Durham, North Carolina, United States of America,Correspondence to: Walter T Lee, Department of Head and Neck Surgery & Communication Sciences, Duke University, Durham, North Carolina, United States of America,
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Lee WT, Ng KW, Liao J, Luk ACS, Suen HC, Chan THT, Cheung MY, Chu D, Zhao M, Chan YL, Li TC, Lee TL. P–547 Single-cell RNA sequencing identifies molecular regulations associated with poor maturation performance on rescue in vitro matured oocytes. Hum Reprod 2021. [DOI: 10.1093/humrep/deab130.546] [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: 11/12/2022] Open
Abstract
Abstract
Study question
What is the transcriptome signature associated with rescuein vitro matured (rIVM) oocytes?
Summary answer
GATA–1/CREB1/WNT signaling axis was repressed in rIVM oocytes of poor quality.
What is known already
rIVM aims to produce mature oocytes (MII) for in vitro fertilization (IVF) through IVM of immature oocytes collected from stimulated ovaries. It is less popular due to limited success rate in infertility treatment. Genetic aberrations, cellular stress, and the absence of cumulus cell support in oocytes could account for the failure of rIVM.
Study design, size, duration
We applied single-cell RNA sequencing (scRNA-seq) to capture the transcriptomes of human in vivo (IVO) oocytes (n = 10) from 7 donors and rIVM oocytes (n = 10) from 10 donors, followed by studying the maternal age effect and ovarian responses on rIVM oocyte transcriptomes.
Participants/materials, setting, methods
Human oocytes were collected from donors aged 28–41 years with a body mass index of < 30. RNA extraction, cDNA generation, library construction and sequencing were performed in one preparation. scRNA-seq data were then processed and analyzed. Selected genes in therIVM vs. IVO comparison were validated by quantitative real-time PCR.
Main results and the role of chance
The transcriptome profiles of rIVM/IVO showed distinctive differences. A total of 1559 differentially expressed genes (DEGs, genes with at least two-fold change and adjusted p < 0.05) were found to be enriched in metabolic processes, biosynthesis, and oxidative phosphorylation. Among these DEGs, we identified a repression of WNT/β-catenin signaling in rIVM when compared with IVO oocytes. We found that estradiol level exhibited a significant age-independent correlation with the IVO mature oocyte ratio (MII ratio). rIVM oocytes with higher MII ratio showed over-represented cellular processes such as anti-apoptosis. To further identify targets that contribute to the poor outcomes of rIVM, we compared oocytes collected from young donors with high MII ratio versus donors of advanced maternal age and revealed CREB1was an important regulator in rIVM. Our study identified GATA–1/CREB1/WNT signaling was repressed in both rIVM condition and rIVM oocytes of low-quality.
Limitations, reasons for caution
In the rIVM oocytes of high- and low-quality comparison, the number of samples was limited after data filtering with stringent selection criteria. For the oocyte stage identification, we were unable to predict the presence of oocyte spindle so polar body extrusion was the only indicator.
Wider implications of the findings: This study showed that GATA–1/CREB1/WNT signaling and antioxidant actions were repressed in rIVM condition and was further downregulated in rIVM oocytes of low-quality, providing us the foundation of subsequent follow-up research on human subjects.
Trial registration number
Not applicable
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Affiliation(s)
- W T Lee
- The Chinese University of Hong Kong, School of Biomedical Sciences, Hong Kong, Hong Kong
| | - K W Ng
- The Chinese University of Hong Kong, School of Biomedical Sciences, Hong Kong, Hong Kong
| | - J Liao
- The Chinese University of Hong Kong, School of Biomedical Sciences, Hong Kong, Hong Kong
| | - A C S Luk
- The Chinese University of Hong Kong, School of Biomedical Sciences, Hong Kong, Hong Kong
| | - H C Suen
- The Chinese University of Hong Kong, School of Biomedical Sciences, Hong Kong, Hong Kong
| | - T H T Chan
- The Chinese University of Hong Kong, School of Biomedical Sciences, Hong Kong, Hong Kong
| | - M Y Cheung
- The Chinese University of Hong Kong, School of Biomedical Sciences, Hong Kong, Hong Kong
| | - D Chu
- The Chinese University of Hong Kong, School of Biomedical Sciences, Hong Kong, Hong Kong
| | - M Zhao
- The Chinese University of Hong Kong, Department of Obstetrics and Gynaecology, Hong Kong, Hong Kong
| | - Y L Chan
- The Chinese University of Hong Kong, Department of Obstetrics and Gynaecology, Hong Kong, Hong Kong
| | - T C Li
- The Chinese University of Hong Kong, Department of Obstetrics and Gynaecology, Hong Kong, Hong Kong
| | - T L Lee
- The Chinese University of Hong Kong, School of Biomedical Sciences, Hong Kong, Hong Kong
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Affiliation(s)
- K H Fung
- Department of Radiology and Imaging, Queen Elizabeth Hospital, Jordan, Hong Kong
| | - W K Tsang
- Department of Radiology and Imaging, Queen Elizabeth Hospital, Jordan, Hong Kong
| | - P C H Kwok
- Department of Radiology and Imaging, Queen Elizabeth Hospital, Jordan, Hong Kong
| | - W T Lee
- Department of Pathology, Queen Elizabeth Hospital, Jordan, Hong Kong
| | - K W Tang
- Department of Radiology and Imaging, Queen Elizabeth Hospital, Jordan, Hong Kong
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Abstract
Efficient and timely diagnosis of head and neck squamous cell carcinoma (HNSCC) is a critical challenge, particularly in low and middle income countries. These regions, which are expected to witness a drastic increase in HNSCC rates, are ill-prepared to handle the diagnostic burden due to limited resources, especially the low ratio of pathologists per population, resulting in delayed diagnosis and treatment. Here, we demonstrate the potential of an alternative diagnostic method as a low-cost, resource-efficient alternative to histopathological analysis. Our novel technology employs unique surface-enhanced Raman scattering (SERS) "nanorattles" targeting cytokeratin nucleic acid biomarkers specific for HNSCC. In this first study using SERS diagnostics for head and neck cancers, we tested the diagnostic accuracy of our assay using patient tissue samples. In a blinded trial, our technique demonstrated a sensitivity of 100% and specificity of 89%, supporting its use as a useful alternative to histopathological diagnosis. The implications of our method are vast and significant in the setting of global health. Our method can provide a rapid diagnosis, allowing for earlier treatment before the onset of distant metastases. In comparison to histopathology, which can take several months in remote limited-resources regions, our method provides a diagnosis within a few hours.
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Affiliation(s)
- P Vohra
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
- Fitzpatrick Institute for Photonics, Duke University, Durham, NC, USA
- Division of Head and Neck Surgery and Communication Sciences, Duke School of Medicine, Durham, NC, USA
| | - P Strobbia
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
- Fitzpatrick Institute for Photonics, Duke University, Durham, NC, USA
| | - H T Ngo
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
- Fitzpatrick Institute for Photonics, Duke University, Durham, NC, USA
- Biomedical Engineering Department, International University, Vietnam National University-Ho Chi Minh City (VNU-HCMC), Ho Chi Minh City, Vietnam
| | - W T Lee
- Division of Head and Neck Surgery and Communication Sciences, Duke School of Medicine, Durham, NC, USA
| | - T Vo-Dinh
- Department of Biomedical Engineering, Duke University, Durham, NC, USA.
- Department of Chemistry, Duke University, Durham, NC, USA.
- Fitzpatrick Institute for Photonics, Duke University, Durham, NC, USA.
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Xu XY, Lee WT, Chan AKY, Lo HS, Shin PKS, Cheung SG. Microplastic ingestion reduces energy intake in the clam Atactodea striata. Mar Pollut Bull 2017; 124:798-802. [PMID: 28038767 DOI: 10.1016/j.marpolbul.2016.12.027] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 11/29/2016] [Accepted: 12/11/2016] [Indexed: 05/27/2023]
Abstract
The effects of microplastic concentrations (10itemsl-1 and 1000itemsl-1) on the physiological responses of Atactodea striata (clearance rate, absorption efficiency, respiration rate) were investigated. The fates of ingested microplastics and the efficiency of depuration in removing ingested microplastics were also studied. A. striata ingested microplastics and the clearance rate was reduced at high concentration of microplastics. Since the respiration rate and absorption efficiency remained unchanged in exposed A. striata, reduction in the clearance rate would reduce the energy intake. Ingestion and retention of microplastics in the body were further limited by the production of pseudofaeces and faeces, and depuration in clean water, resulting in a very small amount of microplastics stored in the body of the clam.
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Affiliation(s)
- X-Y Xu
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - W T Lee
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - A K Y Chan
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - H S Lo
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - P K S Shin
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong; State Key Laboratory in Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - S G Cheung
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong; State Key Laboratory in Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong.
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6
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Vohra P, Ngo HT, Lee WT, Vo Dinh T. Squamous Cell Carcinoma DNA Detection Using Ultrabright SERS Nanorattles and Magnetic Beads for Head and Neck Cancer Molecular Diagnostics. Anal Methods 2017; 9:5550-5556. [PMID: 37131959 PMCID: PMC10151024 DOI: 10.1039/c7ay01913k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
A rise in head and neck cancers in low and middle countries over recent years has prompted the need for low-cost, resource-efficient diagnostic technologies. Standard diagnosis with histopathology is often not feasible due to the low number of trained pathologists in these regions, resulting in delayed diagnosis and treatment. This study presents an alternative diagnostic method to standard histopathology. We developed a surface enhanced raman scattering (SERS) based method to distinguish squamous cell carcinoma from other cell lines. Using a "sandwich" method employing ultrabright SERA nanorattles and magnetic beads, we directly targeted specific nucleic acid markers of squamous cells. Our method was able to detect the presence of squamous cells with high sensitivity and specificity, supporting its potential for use as a diagnostic tool in head and neck fine needle aspirations (FNA).
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Affiliation(s)
- P Vohra
- Duke University, Biomedical Engineering Durham, NC, USA 27708
| | - H T Ngo
- Duke University, Biomedical Engineering Durham, NC, USA 27708
| | - W T Lee
- Duke University Division of Head and Neck Surgery and Communication SciencesDurham, NC, USA
| | - T Vo Dinh
- Duke University, Biomedical Engineering Durham, NC, USA 27708
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7
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Luo X, Tseng LT, Lee WT, Tan TT, Bao NN, Liu R, Ding J, Li S, Lauter V, Yi JB. Probing the magnetic profile of diluted magnetic semiconductors using polarized neutron reflectivity. Sci Rep 2017; 7:6341. [PMID: 28740239 PMCID: PMC5524716 DOI: 10.1038/s41598-017-06793-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 06/16/2017] [Indexed: 11/09/2022] Open
Abstract
Room temperature ferromagnetism has been observed in the Cu doped ZnO films deposited under an oxygen partial pressure of 10-3 and 10-5 torr on Pt (200 nm)/Ti (45 nm)/Si (001) substrates using pulsed laser deposition. Due to the deposition at relatively high temperature (873 K), Cu and Ti atoms diffuse to the surface and interface, which significantly affects the magnetic properties. Depth sensitive polarized neutron reflectometry method provides the details of the composition and magnetization profiles and shows that an accumulation of Cu on the surface leads to an increase in the magnetization near the surface. Our results reveal that the presence of the copper at Zn sites induces ferromagnetism at room temperature, confirming intrinsic ferromagnetism.
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Affiliation(s)
- X Luo
- School of Materials Science and Engineering, UNSW, Sydney, NSW, 2052, Australia
| | - L T Tseng
- School of Materials Science and Engineering, UNSW, Sydney, NSW, 2052, Australia
| | - W T Lee
- Bragg Institute, ANSTO, New Illawarra Road, Lucas Heights, NSW, 2234, Australia
| | - T T Tan
- School of Materials Science and Engineering, UNSW, Sydney, NSW, 2052, Australia
| | - N N Bao
- Department of Materials Science and Engineering, National University of Singapore, 119260, Singapore, Singapore
| | - R Liu
- SIMS Facility, Office of the Deputy-Vice Chancellor (Research and Development), Western Sydney University, Locked Bag 1797, Penrith, New South Wales, 2751, Australia
| | - J Ding
- Department of Materials Science and Engineering, National University of Singapore, 119260, Singapore, Singapore
| | - S Li
- School of Materials Science and Engineering, UNSW, Sydney, NSW, 2052, Australia
| | - V Lauter
- Quantum Condensed Matter Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - J B Yi
- School of Materials Science and Engineering, UNSW, Sydney, NSW, 2052, Australia.
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Chaudhuri R, Thomson NC, McCallum C, O’Pray H, Barclay ST, Murray D, MacBride-Stewart S, Sharma V, Shepherd M, Lee WT. P125 A primary care audit on asthma patients with frequent exacerbations and the potential impact of national review of asthma deaths (NRAD) recommendations. Thorax 2016. [DOI: 10.1136/thoraxjnl-2016-209333.268] [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: 11/04/2022]
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9
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Abstract
A retrospective analysis of cardiac tumors surgically excised in a 14-year period in Hong Kong was performed. The study showed 65 primary tumors (64 cardiac myxomas, one unclassified sarcoma), and one metastatic leiomyosarcoma. All patients were Chinese except a Filipino woman who had a cardiac sarcoma. The incidence of primary cardiac tumors in Hong Kong Chinese was estimated to be 0.83 per million population per year. The mean age of patients at operation was 50. There were 37 females and 27 males with no difference in mean ages between the two groups. The average size of myxoma was 4.7 cm. The anatomic locations of the 64 myxomas were left atrium (60), right atrium (2), mitral valve (1), and atrial septum on both sides (1). The main presenting clinical features were dyspnea (46%), cerebral embolism (32%), and palpitation (27%). No familial or syndromatic case was noted. Well-differentiated glandular structures were found in one right atrial myxoma. The findings were compared with those of a local series of cardiac tumors found at autopsy.
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Affiliation(s)
- K. W. Chan
- Department of Pathology, University of Hong Kong; Department of Pathology, Queen Mary Hospital, Hong Kong
| | - W. T. Lee
- Department of Pathology, University of Hong Kong; Cardiac-thoracic Unit, Hong Kong
| | | | | | - K. H. Fu
- Department of Pathology, Grantham Hospital, Hong Kong
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10
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Abstract
Controlled manipulation of neutron spin is a critical tool for many neutron scattering techniques. We have constructed current-sheet, neutron spin flippers for use in Spin Echo Scattering Angle Measurement (SESAME) that comprise pairs of open-faced solenoids which introduce an abrupt field reversal at a shared boundary. The magnetic fields generated by the coils have been mapped and compared with both an analytical approximation and a numerical boundary integral calculation. The agreement is generally good, allowing the former method to be used for rapid calculations of the Larmor phase acquired by a neutron passing through the flipper. The evolution of the neutron spin through the current sheets inside the flipper is calculated for various geometries of the current-carrying conductors, including different wire shapes, arrangements, and common imperfections. The flipping efficiency is found to be sensitive to gaps between wires and between current sheets. SESAME requires flippers with high fields and flipping planes inclined to the neutron beam. To avoid substantial neutron depolarization, such flippers require an interdigitated arrangement of wires.
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Affiliation(s)
- P Stonaha
- Indiana University Center for the Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47405, USA
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Jiang CY, Tong X, Brown DR, Culbertson H, Graves-Brook MK, Hagen ME, Kadron B, Lee WT, Robertson JL, Winn B. Spin exchange optical pumping based polarized 3He filling station for the Hybrid Spectrometer at the Spallation Neutron Source. Rev Sci Instrum 2013; 84:065108. [PMID: 23822379 DOI: 10.1063/1.4809942] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The Hybrid Spectrometer (HYSPEC) is a new direct geometry spectrometer at the Spallation Neutron Source at the Oak Ridge National Laboratory. This instrument is equipped with polarization analysis capability with 60° horizontal and 15° vertical detector coverages. In order to provide wide angle polarization analysis for this instrument, we have designed and built a novel polarized (3)He filling station based on the spin exchange optical pumping method. It is designed to supply polarized (3)He gas to HYSPEC as a neutron polarization analyzer. In addition, the station can optimize the (3)He pressure with respect to the scattered neutron energies. The depolarized (3)He gas in the analyzer can be transferred back to the station to be repolarized. We have constructed the prototype filling station. Preliminary tests have been carried out demonstrating the feasibility of the filling station. Here, we report on the design, construction, and the preliminary results of the prototype filling station.
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Affiliation(s)
- C Y Jiang
- Instrument and Source Design Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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Wieking BG, Vermeer DW, Spanos WC, Lee KM, Vermeer P, Lee WT, Xu Y, Gabitzsch ES, Balcaitis S, Balint JP, Jones FR, Lee JH. A non-oncogenic HPV 16 E6/E7 vaccine enhances treatment of HPV expressing tumors. Cancer Gene Ther 2012; 19:667-74. [PMID: 22918471 PMCID: PMC3571619 DOI: 10.1038/cgt.2012.55] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Human papillomaviruses (HPVs) are the causative factor for >90% of cervical cancers and 25% of head and neck cancers. The incidence of HPV positive (+) head and neck squamous cell carcinomas has greatly increased in the last 30 years. E6 and E7 are the two key viral oncoproteins that induce and propagate cellular transformation. An immune response generated during cisplatin/radiation therapy improves tumor clearance of HPV(+) cancers. Augmenting this induced response during therapy with an adenoviral HPV16 E6/E7 vaccine improves long-term survival in pre-clinical models. Here, we describe the generation of an HPV16 E6/E7 construct, which contains mutations that render E6/E7 non-oncogenic, while preserving antigenicity. These mutations do not allow E6/E7 to degrade p53, pRb, PTPN13, or activate telomerase. Non-oncogenic E6/E7 (E6(Δ)/E7(Δ)) expressed as a stable integrant, or in the [E1-, E2b-] adenovirus, lacks the ability to transform human cells while retaining the ability to induce an HPV-specific immune response. Moreover, E6(Δ)/E7(Δ) plus chemotherapy/radiation statistically enhances clearance of established HPV(+) cancer in vivo.
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Affiliation(s)
- B G Wieking
- Cancer Biology Research Center, Sanford Research/University of South Dakota, Sioux Falls, SD 57104, USA
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Tong X, Jiang CY, Lauter V, Ambaye H, Brown D, Crow L, Gentile TR, Goyette R, Lee WT, Parizzi A, Robertson JL. In situ polarized 3He system for the Magnetism Reflectometer at the Spallation Neutron Source. Rev Sci Instrum 2012; 83:075101. [PMID: 22852718 DOI: 10.1063/1.4731261] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We report on the in situ polarized (3)He neutron polarization analyzer developed for the time-of-flight Magnetism Reflectometer at the Spallation Neutron Source at Oak Ridge National Laboratory. Using the spin exchange optical pumping method, we achieved a (3)He polarization of 76% ± 1% and maintained it for the entire three-day duration of the test experiment. Based on transmission measurements with unpolarized neutrons, we show that the average analyzing efficiency of the (3)He system is 98% for the neutron wavelength band of 2-5 Å. Using a highly polarized incident neutron beam produced by a supermirror bender polarizer, we obtained a flipping ratio of >100 with a transmission of 25% for polarized neutrons, averaged over the wavelength band of 2-5 Å. After the cell was depolarized for transmission measurements, it was reproducibly polarized and this performance was maintained for three weeks. A high quality polarization analysis experiment was performed on a reference sample of Fe/Cr multilayer with strong spin-flip off-specular scattering. Using a combination of the position sensitive detector, time-of-flight method, and the excellent parameters of the (3)He cell, the polarization analysis of the two-dimensional maps of reflected, refracted, and off-specular scattered intensity above and below the horizon were obtained, simultaneously.
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Affiliation(s)
- X Tong
- Instrument and Source Design Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6393, USA.
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Lee WT, McKechnie JS, Devereux MG. Bubble nucleation in stout beers. Phys Rev E Stat Nonlin Soft Matter Phys 2011; 83:051609. [PMID: 21728549 DOI: 10.1103/physreve.83.051609] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 04/10/2011] [Indexed: 05/31/2023]
Abstract
Bubble nucleation in weakly supersaturated solutions of carbon dioxide-such as champagne, sparkling wines, and carbonated beers-is well understood. Bubbles grow and detach from nucleation sites: gas pockets trapped within hollow cellulose fibers. This mechanism appears not to be active in stout beers that are supersaturated solutions of nitrogen and carbon dioxide. In their canned forms these beers require additional technology (widgets) to release the bubbles which will form the head of the beer. We extend the mathematical model of bubble nucleation in carbonated liquids to the case of two gases and show that this nucleation mechanism is active in stout beers, though substantially slower than in carbonated beers and confirm this by observation. A rough calculation suggests that despite the slowness of the process, applying a coating of hollow porous fibers to the inside of a can or bottle could be a potential replacement for widgets.
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Affiliation(s)
- W T Lee
- MACSI, Department of Mathematics and Statistics, University of Limerick, Limerick, Ireland.
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16
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Wassenberg T, Willemsen MAAP, Geurtz PBH, Lammens M, Verrijp K, Wilmer M, Lee WT, Wevers RA, Verbeek MM. Urinary dopamine in aromatic L-amino acid decarboxylase deficiency: the unsolved paradox. Mol Genet Metab 2010; 101:349-56. [PMID: 20832343 DOI: 10.1016/j.ymgme.2010.08.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Revised: 08/04/2010] [Accepted: 08/04/2010] [Indexed: 01/11/2023]
Abstract
INTRODUCTION In aromatic L-amino acid decarboxylase (AADC) deficiency, a neurotransmitter biosynthesis defect, paradoxical normal or increased levels of urinary dopamine have been reported. Genotype/phenotype correlations or alternative metabolic pathways may explain this remarkable finding, but were never studied systematically. METHODS We studied the mutational spectrum and urinary dopamine levels in 20 patients with AADC-deficiency. Experimental procedures were designed to test for alternative metabolic pathways of dopamine production, which included alternative substrates (tyramine and 3-methoxytyrosine) and alternative enzymes (tyrosinase and CYP2D6). RESULTS/DISCUSSION In 85% of the patients the finding of normal or increased urinary levels of dopamine was confirmed, but a relation with AADC genotype could not be identified. Renal microsomes containing CYP2D were able to convert tyramine into dopamine (3.0 nmol/min/g protein) but because of low plasma levels of tyramine this is an unlikely explanation for urinary dopamine excretion in AADC-deficiency. No evidence was found for the production of dopamine from 3-methoxytyrosine. Tyrosinase was not expressed in human kidney. CONCLUSION Normal or increased levels of urinary dopamine are found in the majority of AADC-deficient patients. This finding can neither be explained by genotype/phenotype correlations nor by alternative metabolic pathways, although small amounts of dopamine may be formed via tyramine hydroxylation by renal CYP2D6. CYP2D6-mediated conversion of tyramine into dopamine might be an interesting target for the development of new therapeutic strategies in AADC-deficiency.
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Affiliation(s)
- T Wassenberg
- Radboud University Nijmegen Medical Centre, Department of Neurology, Neurochemistry Lab, Nijmegen, The Netherlands.
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Mavroeidi A, O'Neill F, Lee PA, Darling AL, Fraser WD, Berry JL, Lee WT, Reid DM, Lanham-New SA, Macdonald HM. Seasonal 25-hydroxyvitamin D changes in British postmenopausal women at 57 degrees N and 51 degrees N: a longitudinal study. J Steroid Biochem Mol Biol 2010; 121:459-61. [PMID: 20302933 DOI: 10.1016/j.jsbmb.2010.03.038] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2009] [Revised: 02/24/2010] [Accepted: 03/08/2010] [Indexed: 11/30/2022]
Abstract
The UK has insufficient intensity of sunlight at wavelengths 290-315 nm to enable cutaneous synthesis of vitamin D from October to April. There are regional differences in UVB strength throughout the UK but whether this translates to differences in vitamin D status is not known. We have reported seasonal variations in a cross-sectional study of over 3000 Scottish women in Aberdeen. The aim of this longitudinal study was to compare the seasonal variation of serum 25-hydroxyvitamin D [25(OH)D] in postmenopausal women residing in Aberdeen (57 degrees N) and Surrey (51 degrees N). Women attended 3-monthly visits over 12 months, starting summer 2006. In Aberdeen, 338 Caucasian women (mean age+/-SD, 61.7+/-1.5 years); and at Surrey, 138 Caucasian women (61.4+/-4.5 years) and 35 Asian women (59.9+/-6.4 years) had serum 25(OH)D measured by IDS enzyme immunoassay. In winter/spring none of the Caucasian women living in Surrey had 25(OH)D<20 nmol/L, but nearly a quarter of women in Aberdeen were vitamin D-deficient. This number decreased to 4.2% in summer/autumn. For the Asian women 17.1% were vitamin D-deficient in summer, increasing to 58.1% in winter. Using higher 25(OH)D deficiency cut-offs, the percentage of women affected was much higher. These longitudinal data show clear differences in vitamin D status between the north and south of the UK, and marked ethnic differences. They are consistent with our previous data and with cross-sectional data from the 1958 birth cohort. The low vitamin D status may have implications for bone health and other health outcomes, which is currently being investigated in this publication group. The extent of vitamin D deficiency in Asian women residing in the South of England is of concern.
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Affiliation(s)
- A Mavroeidi
- Bone and Musculoskeletal Research Programme, University of Aberdeen, UK.
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Brun L, Ngu LH, Keng WT, Ch'ng GS, Choy YS, Hwu WL, Lee WT, Willemsen MAAP, Verbeek MM, Wassenberg T, Régal L, Orcesi S, Tonduti D, Accorsi P, Testard H, Abdenur JE, Tay S, Allen GF, Heales S, Kern I, Kato M, Burlina A, Manegold C, Hoffmann GF, Blau N. Clinical and biochemical features of aromatic L-amino acid decarboxylase deficiency. Neurology 2010; 75:64-71. [PMID: 20505134 DOI: 10.1212/wnl.0b013e3181e620ae] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To describe the current treatment; clinical, biochemical, and molecular findings; and clinical follow-up of patients with aromatic l-amino acid decarboxylase (AADC) deficiency. METHOD Clinical and biochemical data of 78 patients with AADC deficiency were tabulated in a database of pediatric neurotransmitter disorders (JAKE). A total of 46 patients have been previously reported; 32 patients are described for the first time. RESULTS In 96% of AADC-deficient patients, symptoms (hypotonia 95%, oculogyric crises 86%, and developmental retardation 63%) became clinically evident during infancy or childhood. Laboratory diagnosis is based on typical CSF markers (low homovanillic acid, 5-hydroxyindoleacidic acid, and 3-methoxy-4-hydroxyphenolglycole, and elevated 3-O-methyl-l-dopa, l-dopa, and 5-hydroxytryptophan), absent plasma AADC activity, or elevated urinary vanillactic acid. A total of 24 mutations in the DDC gene were detected in 49 patients (8 reported for the first time: p.L38P, p.Y79C, p.A110Q, p.G123R, p.I42fs, c.876G>A, p.R412W, p.I433fs) with IVS6+ 4A>T being the most common one (allele frequency 45%). CONCLUSION Based on clinical symptoms, CSF neurotransmitters profile is highly indicative for the diagnosis of aromatic l-amino acid decarboxylase deficiency. Treatment options are limited, in many cases not beneficial, and prognosis is uncertain. Only 15 patients with a relatively mild form clearly improved on a combined therapy with pyridoxine (B6)/pyridoxal phosphate, dopamine agonists, and monoamine oxidase B inhibitors.
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Affiliation(s)
- L Brun
- Division of Clinical Chemistry and Biochemistry, University Children's Hospital, Steinwiesstrasse 75, CH-8032 Zürich, Switzerland.
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Ashkar R, Stonaha P, Washington AL, Shah VR, Fitzsimmons MR, Maranville B, Majkrzak CF, Lee WT, Schaich WL, Pynn R. Dynamical theory calculations of spin-echo resolved grazing-incidence scattering from a diffraction grating. J Appl Crystallogr 2010. [DOI: 10.1107/s0021889810010642] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Neutrons scattered or reflected from a diffraction grating are subject to a periodic potential analogous to the potential experienced by electrons within a crystal. Hence, the wavefunction of the neutrons can be expanded in terms of Bloch waves and a dynamical theory can be applied to interpret the scattering phenomenon. In this paper, a dynamical theory is used to calculate the results of neutron spin-echo resolved grazing-incidence scattering (SERGIS) from a silicon diffraction grating with a rectangular profile. The calculations are compared with SERGIS measurements made on the same grating at two neutron sources: a pulsed source and a continuous wave source. In both cases, the spin-echo polarization, studied as a function of the spin-echo length, peaks at integer multiples of the grating period but there are some differences between the two sets of data. The dynamical theory explains the differences and gives a good account of both sets of results.
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Abstract
Recent experimental work has shown that, when a vertical column of rock under large pressure is suddenly depressurized, the column can ‘explode’ in a structured and repeatable way. The observations show that a sequence of horizontal fractures forms from the top down, and the resulting blocks are lifted off and ejected. The blocks can suffer secondary internal fractures. This experiment provides a framework for understanding the way in which catastrophic explosion can occur, and is motivated by the corresponding phenomenon of magmatic explosion during Vulcanian eruptions. We build a theoretical model to describe these results, and show that it is capable of describing both the primary sequence of fracturing and the secondary intrablock fracturing. The model allows us to suggest a practical criterion for when such explosions occur: firstly, the initial confining pressure must exceed the yield stress of the rock, and, secondly, the diffusion of the gas by porous flow must be sufficiently slow that a large excess pore pressure is built up. This will be the case if the rock permeability is small enough.
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Affiliation(s)
- A. C. Fowler
- MACSI, Department of Mathematics and Statistics, University of Limerick, Limerick, Republic of Ireland
| | - Bettina Scheu
- Earth and Environmental Sciences, LMU München, Theresienstrasse 41/111, 80333 München, Germany
| | - W. T. Lee
- MACSI, Department of Mathematics and Statistics, University of Limerick, Limerick, Republic of Ireland
| | - M. J. McGuinness
- School of Mathematics, Statistics and Operations Research, Victoria University of Wellington, New Zealand
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Abstract
Phase synchronization is an important phenomenon of nonlinear dynamics and has recently received much scientific attention. In this work a method for identifying phase synchronization epochs is described which focuses on estimating the gradient of segments of the generalized phase differences between phase slips in an experimental time series. In phase synchronized systems, there should be a zero gradient of the generalized phase differences even if the systems are contaminated by noise. A method which tests if the gradient of the generalized phase difference is statistically different from zero is reported. The method has been validated by numerical studies on model systems and by comparing the results to those published previously. The method is applied to cardiorespiratory time series from a human volunteer measured in clinical settings and compared to synchrogram analysis for the same data. Potential problems with synchrogram analysis of experimental data are discussed.
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Affiliation(s)
- Martin Vejmelka
- Institute of Computer Science, Academy of Sciences of the Czech Republic, Praha 182 07, Czech Republic.
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Rodriguez CP, Adelstein DJ, Saxton JP, Rybicki LA, Lorenz RR, Wood BG, Scharpf J, Lee WT, Ives DI. Multiagent concurrent chemoradiotherapy (MACCRT) and gefitinib in locoregionally advanced head and neck squamous cell cancer (HNSCC). J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.6037] [Citation(s) in RCA: 2] [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: 11/20/2022] Open
Abstract
6037 Background: In patients (pts) with stage III-IV HNSCC, MACCRT has led to excellent locoregional control. Distant metastases (DM) are now the most common cause of treatment failure. This phase II study tested whether the oral EGFR inhibitor gefitinib (G) added to our Cleveland Clinic MACCRT regimen would decrease DM and improve survival. Methods: Between 4/03 and 9/07, 60 previously untreated pts with stage III-IV (M0) HNSCC, and a performance status of <1 were enrolled on this study. Pts received hyperfractionated radiation (72–74.4 Gy at 120cGy bid) and concurrent chemotherapy with cisplatin (20 mg/m2/day) and fluorouracil (1,000 mg/m2/day), both given as 96-hour continuous IV infusions during weeks 1 and 4. G 250 mg daily was begun on day 1 of the radiation and continued for 2 years. The results were retrospectively compared to our previous study of 44 pts treated with the same MACCRT regimen without G between 1/96 and 9/00. Results: The study population included a preponderance of Caucasian (97%) males (88%) with stage IV (80%) oropharynx tumors (68%), and with a median age of 58 (range 24–75) years. Patient and tumor characteristics were similar to the non-G treated historical cohort. When comparing the G vs. non-G treated pts, acute toxicities including transient renal dysfunction (28% v. 5% p = 0.002) and all-cause re-hospitalization (83% v. 64%, p = 0.022) were worse. Myelosuppression was similar. G-specific toxicity included > grade 1 rash in 60% and diarrhea in 35%. There were 5 deaths during treatment in the G group v. one in the non-G group (p = 0.19). Only a projected 44% of pts will complete the 2-year course of G. With a median follow-up in this trial of 37 (range 13–64) months, 3-year Kaplan-Meier outcome estimates do not differ between the study and the historical cohorts. Local control without surgery is 80% v. 88% (p = 0.21), DM control is 86% v. 76% (p = 0.19), freedom from recurrence is 72% v. 71% (p = 0.79), and overall survival is 67% v. 68% (p = 0.63) respectively. Conclusions: The addition of G to our MACCRT regimen was difficult for pts to complete. It did not improve any measured outcome and was associated with increased toxicity when compared to historical controls. [Table: see text]
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Affiliation(s)
- C. P. Rodriguez
- Cleveland Clinic Foundation, Cleveland, OH; Duke University Medical Center, Durham, NC
| | - D. J. Adelstein
- Cleveland Clinic Foundation, Cleveland, OH; Duke University Medical Center, Durham, NC
| | - J. P. Saxton
- Cleveland Clinic Foundation, Cleveland, OH; Duke University Medical Center, Durham, NC
| | - L. A. Rybicki
- Cleveland Clinic Foundation, Cleveland, OH; Duke University Medical Center, Durham, NC
| | - R. R. Lorenz
- Cleveland Clinic Foundation, Cleveland, OH; Duke University Medical Center, Durham, NC
| | - B. G. Wood
- Cleveland Clinic Foundation, Cleveland, OH; Duke University Medical Center, Durham, NC
| | - J. Scharpf
- Cleveland Clinic Foundation, Cleveland, OH; Duke University Medical Center, Durham, NC
| | - W. T. Lee
- Cleveland Clinic Foundation, Cleveland, OH; Duke University Medical Center, Durham, NC
| | - D. I. Ives
- Cleveland Clinic Foundation, Cleveland, OH; Duke University Medical Center, Durham, NC
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Fraser KH, Li MX, Lee WT, Easson WJ, Hoskins PR. Fluid—structure interaction in axially symmetric models of abdominal aortic aneurysms. Proc Inst Mech Eng H 2008; 223:195-209. [DOI: 10.1243/09544119jeim443] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Abdominal aortic aneurysm disease progression is probably influenced by tissue stresses and blood flow conditions and so accurate estimation of these will increase understanding of the disease and may lead to improved clinical practice. In this work the blood flow and tissue stresses in axially symmetric aneurysms are calculated using a complete fluid—structure interaction as a benchmark for calculating the error introduced by simpler calculations: rigid walled for the blood flow, homogeneous pressure for the tissue stress, as well as one-way-coupled interactions. The error in the peak von Mises stress in a homogeneous pressure calculation compared with a fluid—structure interaction calculation was less than 3.5 per cent for aneurysm diameters up to 7 cm. The error in the mean wall shear stress, in a rigid-walled calculation compared with a fluid—structure interaction calculation, varied from 30 per cent to 60 per cent with increasing aneurysm diameter. These results suggest that incorporation of the fluid—structure interaction is unnecessary for purely mechanical modelling, with the aim of evaluating the current rupture probability. However, for more complex biological modelling, perhaps with the aim of predicting the progress of the disease, where accurate estimation of the wall shear stress is essential, some form of fluid—structure interaction is necessary.
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Affiliation(s)
- K H Fraser
- Department of Medical Physics, The University of Edinburgh, Edinburgh, UK
| | - M-X Li
- School of Engineering and Electronics, The University of Edinburgh, Edinburgh, UK
| | - W T Lee
- School of Engineering and Electronics, The University of Edinburgh, Edinburgh, UK
| | - W J Easson
- School of Engineering and Electronics, The University of Edinburgh, Edinburgh, UK
| | - P R Hoskins
- Department of Medical Physics, The University of Edinburgh, Edinburgh, UK
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Pynn R, Fitzsimmons MR, Lee WT, Shah VR, Washington AL, Stonaha P, Littrell K. Spin echo scattering angle measurement at a pulsed neutron source. J Appl Crystallogr 2008. [DOI: 10.1107/s0021889808020402] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Two experiments were performed to adapt spin echo scattering angle measurement (SESAME) to pulsed neutron sources. SESAME is an interferometric method that provides enhanced resolution of neutron scattering angles without the loss of neutron intensity that results when collimation is used to improve angular resolution. The method uses the neutron equivalent of optical wave plates to produce a phase difference between the two neutron spin components of a polarized neutron beam. Because the wave plate is inclined to the neutron beam, this phase difference depends sensitively on the trajectory of the neutron. In the absence of a sample, a second wave plate, which is parallel to the first, undoes the phase difference introduced by the first wave plate, producing a polarization identical to that of the incident neutron beam. When a scattering sample is placed between the two neutron wave plates, the cancellation of the phase difference between the neutron spin states is not perfect and the resulting neutron-beam polarization is a measure of the distribution of scattering angles. In the first experiment, thin (30 and 60 µm-thick) magnetized Permalloy films were used as neutron wave plates. In a second experiment, current-carrying solenoids with triangular cross sections were used as birefringent prisms for neutrons. The arrangement of these prisms was such that they mimicked the effect of the neutron wave plates in the first experiment. In both experiments, correlation lengths in the scattering sample of about 1000 Å were probed using very simple and inexpensive equipment. These experiments brought to light a number of advantages and disadvantages of implementing SESAME at pulsed neutron sources and provided insights into the relative merits of SESAME and traditional small-angle neutron scattering.
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Pynn R, Lee WT, Stonaha P, Shah VR, Washington AL, Kirby BJ, Majkrzak CF, Maranville BB. The use of symmetry to correct Larmor phase aberrations in spin echo scattering angle measurement. Rev Sci Instrum 2008; 79:063901. [PMID: 18601411 DOI: 10.1063/1.2927251] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Spin echo scattering angle measurement (SESAME) is a sensitive interference technique for measuring neutron diffraction. The method uses waveplates or birefringent prisms to produce a phase separation (the Larmor phase) between the "up" and "down" spin components of a neutron wavefunction that is initially prepared in a state that is a linear combination of in-phase up and down components. For neutrons, uniformly birefringent optical elements can be constructed from closed solenoids with appropriately shaped cross sections. Such elements are inconvenient in practice, however, both because of the precision they demand in the control of magnetic fields outside the elements and because of the amount of material required in the neutron beam. In this paper, we explore a different option in which triangular-cross-section solenoids used to create magnetic fields for SESAME have gaps in one face, allowing the lines of magnetic flux to "leak out" of the solenoid. Although the resulting field inhomogeneity produces aberrations in the Larmor phase, the symmetry of the solenoid gaps causes the aberrations produced by neighboring pairs of triangular solenoids to cancel to a significant extent. The overall symmetry of the SESAME apparatus leads to further cancellations of aberrations, providing an architecture that is easy to construct and robust in performance.
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Affiliation(s)
- Roger Pynn
- Physics Department, Indiana University, Bloomington, IN 47405, USA
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27
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Lin YY, Shih YH, Chang KP, Lee WT, Yu HY, Hsieh JC, Yeh TC, Wu ZA, Ho LT. MEG localization of rolandic spikes with respect to SI and SII cortices in benign rolandic epilepsy. Neuroimage 2004; 20:2051-61. [PMID: 14683709 DOI: 10.1016/j.neuroimage.2003.08.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [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: 10/26/2022] Open
Abstract
The purpose of this study was to study the relationship between interictal spike sources and somatosensory cortices in benign rolandic epilepsy of childhood (BREC) using a whole-scalp neuromagnetometer. We recorded spontaneous magnetoencephalography (MEG) and EEG signals and cortical somatosensory-evoked magnetic fields (SEFs) to electric stimulation of the median nerve in 9 children with BREC. Interictal rolandic discharges (RDs) and SEFs were analyzed by equivalent current dipole (ECD) modeling. Based on the orientation and locations of corresponding ECDs, we compared generators of RDs with primary (SI) and second somatosensory cortices (SII). Our results showed that RDs and SII responses had similar ECD orientation on the magnetic field maps. The ECDs of RDs were localized 15.3 +/- 1.9 and 12.2 +/- 2.8 mm anterior to SI and SII, respectively. The spatial distance on average from the location of RDs to SII (21.9 +/- 1.6 mm) cortex was significantly shorter than to SI cortex (29.7 +/- 1.7 mm) (P<0.01, Wilcoxon signed-rank test). In conclusion, the cortical generators for RDs in patients with BREC are localized in the precentral motor cortex, closer to hand SII than to SI cortex.
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Affiliation(s)
- Y Y Lin
- Integrated Brain Research Unit, Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan.
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Lee JT, Lam ZCM, Lee WT, Kuo LCT, Jayant V, Singh G, Lee J. Familial risk of allergic rhinitis and atopic dermatitis among Chinese families in Singapore. Ann Acad Med Singap 2004; 33:71-4. [PMID: 15008567] [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: 04/29/2023]
Abstract
INTRODUCTION This study aims to determine the familial risk of atopic dermatitis (AD) and allergic rhinitis (AR) in Chinese children. MATERIALS AND METHODS A cross-sectional study was conducted in a housing estate in Singapore. Data was collected using an interviewer-administered questionnaire. Participants included 257 Chinese families. Prevalence rate ratios (PRRs) and 95% confidence interval (CI) were calculated. RESULTS For AD in all children, an increasing trend was found with PRRs of 1.9 (95% CI, 0.3 to 11.8) and 1.5 (95% CI, 0.4 to 5.5) for only father and only mother affected, respectively, to 2.3 (95% CI, 0.4 to 13.7) for both parents affected. In AR, a PRR of 2.7 (95% CI, 1.8 to 3.9) and 2.2 (95% CI, 1.5 to 3.2) for only father and only mother affected, respectively, and 4.5 (95% CI, 3.3 to 6.1) for both affected was found. The PRR (2.2; 95% CI, 1.4 to 3.7) of the first child developing AR when paternal or maternal history was positive was similar. This rose to 3.4 (95% CI, 2.2 to 5.1) when both parents also had AR. The PRR of the second child developing AR was 3.9 (95% CI, 1.7 to 8.9) when the first child alone was positive for AR and 7.0 (95% CI, 3.5 to 13.9) when both parents and the eldest child had AR. CONCLUSION A positive family history increases the risk of developing AD and AR with increasing risk dependent on number of relatives affected. The second child's risk of AR is also associated with AR in the first child, suggesting mechanisms of incomplete penetrance.
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Affiliation(s)
- J T Lee
- Faculty of Medicine, National University of Singapore, Singapore.
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Lee WT, Yin HS, Shen YZ. The mechanisms of neuronal death produced by mitochondrial toxin 3-nitropropionic acid: the roles of N-methyl-D-aspartate glutamate receptors and mitochondrial calcium overload. Neuroscience 2002; 112:707-16. [PMID: 12074912 DOI: 10.1016/s0306-4522(02)00097-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [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: 11/20/2022]
Abstract
Previous studies showed that 3-nitropropionic acid, an irreversible inhibitor of succinate dehydrogenase, produced neuronal death secondary to perturbed intracellular calcium homeostasis. However, the response of intramitochondrial calcium ([Ca(2+)](m)) to 3-nitropropionic acid remains unknown. In this study, we investigated the roles of and relationships among [Ca(2+)](m) overload, mitochondrial reactive oxygen species, and mitochondrial membrane depolarization in 3-nitropropionic acid-induced neuronal death. Following 1 mM 3-nitropropionic acid treatment on primary rat neuronal cultures, there was a gradual increase of [Ca(2+)](m) beginning at 2-4 h post 3-nitropropionic acid application, and a twofold increase of mitochondrial reactive oxygen species at 4 h. These were followed by mitochondrial membrane depolarization at 6-8 h post-treatment. By inhibiting [Ca(2+)](m) uptake, Ruthenium Red attenuated the production of reactive oxygen species, and prevented the 3-nitropropionic acid-induced mitochondrial membrane depolarization and 70% of apoptotic neuronal death (P<0.001). Inhibition of caspase activation attenuated the elevation of [Ca(2+)](m) (P<0.001), indicating that caspase activation plays a role in the elevation of [Ca(2+)](m). MK-801, an antagonist of N-methyl-D-aspartate (NMDA) glutamate receptors, prevented 3-nitropropionic acid-induced [Ca(2+)](m) elevation, caspase-3 activation, mitochondrial depolarization, and neuronal death. We conclude that the activation of NMDA glutamate receptor contributes to mitochondrial alterations induced by 3-nitropropionic acid. Inhibition of its activation and [Ca(2+)](m) overload with subsequent mitochondrial membrane depolarization can therefore attenuate the neuronal death induced by 3-nitropropionic acid.
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Affiliation(s)
- W T Lee
- Department of Pediatrics, College of Medicine, National Taiwan University, Taipei, Taiwan
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Chen PT, Young C, Lee WT, Wang PJ, Peng SS, Shen YZ. Early epileptic encephalopathy with suppression burst electroencephalographic pattern--an analysis of eight Taiwanese patients. Brain Dev 2001; 23:715-20. [PMID: 11701284 DOI: 10.1016/s0387-7604(01)00285-6] [Citation(s) in RCA: 16] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Early epileptic encephalopathy with suppression burst (SB) comprises two distinct epileptic syndromes, early infantile epileptic encephalopathy (EIEE) and early myoclonic encephalopathy (EME). We reviewed etiologies, neurological outcome and clinico-electroencephalographic features of EIEE and EME. Chart records of early epileptic encephalopathy with SB from January 1997 to December 2000 were reviewed. These cases fulfilled the diagnostic criteria of EIEE and EME. Totally eight patients (four females, four males) were enrolled. They consisted of three cases of EIEE and five cases of EME. The follow-up periods ranged from 6 to 30 months. For EIEE, two cases had migrational disorders, and one was cryptogenic; for EME, three cases had non-ketotic hyperglycinemia (NKH), one was pyridoxine dependency and one was cryptogenic. The main initial seizure patterns were tonic spasms in EIEE, and were erratic myoclonus in EME. The age of seizure onset ranged from 26 h to 5 days after birth for EIEE, and 2 h to 7 days of life for EME. The SB pattern in the electroencephalography (EEG) was noted mainly during sleep state in EME, but in both awake and sleep states in EIEE. Asymmetric SB pattern and background activities in EEG were found in migrational disorders. The EEG in all cases of EIEE changed to hypsarrhythmia at 4-6 months of age. In EME, only the EEG in cases of NKH evolved to hypsarrhythmia. Response to anti-convulsants was generally poor. All had severe psychomotor retardation. Although EIEE and EME share several common features, differences in terms of seizure seminology and evolution, EEG patterns and etiologies still exist.
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Affiliation(s)
- P T Chen
- Department of Pediatrics, Cardinal Tien Hospital, No. 362, Chung-Cheng Road, Hsintien City, Taipei, Taiwan.
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Lee WT, Lee JE, Lee SH, Jang HS, Giffard RG, Park KA. Human papilloma virus type 16 E7 genes protect astrocytes against apoptotic and necrotic death induced by hydrogen peroxide. Yonsei Med J 2001; 42:471-9. [PMID: 11675674 DOI: 10.3349/ymj.2001.42.5.471] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Hydrogen peroxide is considered to be a dose- and time-dependent mediator in apoptotic and necrotic death. In this study, we examined the signaling of the E6 and E7 proteins with respect to apoptosis or necrosis after H2O2 injury using an in vitro model with overexpressed E6 or E7 genes. For this purpose, the E6 and E7 gene expressing astrocytes were exposed to 10 micromole and 200 micromole H2O2 solutions. Twenty- four hours after treatment with the lower dosage(10 micromole H2O2), control, E6-expressing cells suffered about 45% injury and LXSN-expressing cells decreased by 67% as assessed by LDH release. However, E7-expressing cells showed less injury, resulting in 20-30% of LDH release. Astrocytes expressing E6, E7, LXSN and mock-infected cells showed a typical apoptotic death pattern on the DNA gel after treatment with a low-dose of H2O2 (10 micromole), however they died from necrotic death after a high-dose (200 micromole) H2O2. Overexpression of HPV-E7 genes protected the cells from apoptotic death after a low-dose of H2O2 and from necrotic death after a high-dose of H2O2, while the overexpression of E6 genes from the necrotic death. E7 expressing astrocytes showed higher catalase activity and the levels of E2F protein surged more than 100-folds compared with the control astrocytes. We believe that the activity of E7 protein to protect astrocytes from H2O2 injury was at least partly due to increased catalase, a scavenger protein.
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Affiliation(s)
- W T Lee
- Department of Anatomy, Yonsei University College of Medicine, C.P.O. Box 8044, Seoul 120-752, Korea
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Lu C, Chan SL, Haughey N, Lee WT, Mattson MP. Selective and biphasic effect of the membrane lipid peroxidation product 4-hydroxy-2,3-nonenal on N-methyl-D-aspartate channels. J Neurochem 2001; 78:577-89. [PMID: 11483661 DOI: 10.1046/j.1471-4159.2001.00431.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [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: 11/20/2022]
Abstract
Increased oxyradical production and membrane lipid peroxidation occur in neurons under physiological conditions and in neurodegenerative disorders. Lipid peroxidation can alter synaptic plasticity and may increase the vulnerability of neurons to excitotoxicity, but the underlying mechanisms are unknown. We report that 4-hydroxy-2,3-nonenal (4HN), an aldehyde product of lipid peroxidation, exerts a biphasic effect on NMDA-induced current in cultured rat hippocampal neurons with current being increased during the first 2 h and decreased after 6 h. Similarly, 4HN causes an early increase and a delayed decrease in NMDA-induced elevation of intracellular Ca2+ levels. In contrast, 4HN affects neither the ion current nor the Ca2+ response to alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA). The initial enhancement of NMDA-induced current is associated with increased phosphorylation of the NR1 receptor subunit, whereas the delayed suppression of current is associated with cellular ATP depletion and mitochondrial membrane depolarization. Cell death induced by 4HN is attenuated by an NMDA receptor antagonist, but not by an AMPA receptor antagonist. A secreted form of amyloid precursor protein, previously shown to protect neurons against oxidative and excitotoxic insults, prevented each of the effects of 4HN including the early and late changes in NMDA current, delayed ATP depletion, and cell death. These findings show that the membrane lipid peroxidation product 4HN can modulate NMDA channel activity, suggesting a role for this aldehyde in physiological and pathophysiological responses of neurons to oxidative stress.
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Affiliation(s)
- C Lu
- Laboratory of Neurosciences, National Institute on Aging Gerontology Research Center, Baltimore 21224, USA
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33
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Abstract
Catalytic incineration is one of the cost-effective technologies to solve the troublesome VOCs. However, some sulfur containing VOCs, such as ethyl mercaptan and dimethyl disulfide, may deactivate the Pt catalyst that is commonly used in the catalytic incineration process. The catalytic incineration of these compounds over a Pt/Al2O3 catalyst was carried out in a bench scale catalytic incinerator. Three kinetic models, such as power-rate law, Mars and Van Krevelen model, and Langmuir-Hinshelwood model were used to analyze the results. A differential reactor design was used for best fit of kinetic models in this study. The results show that the Langmuir-Hinshelwood model is feasible to describe the catalytic incineration of both C2H5SH and (CH3)2S2. This suggests that the chemical adsorption of O2 molecule is important in the process of catalytic incineration of C2H5SH and (CH3)2S2.
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Affiliation(s)
- H Chu
- Department of Environmental Engineering, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan
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34
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Abstract
Catalytic incineration is one of the cost-effective technologies to solve the troublesome volatile organic compounds (VOCs). However, some sulfur containing VOCs, such as dimethyl sulfide, may deactivate the Pt catalyst that is commonly used in the catalytic incineration process. This paper provides information on the poisoning effect of (CH3)2S. The catalytic incineration of (CH3)2S, typically emitted from the petrochemical industry, over a Pt/Al(2)O(3) fixed bed catalytic reactor was studied. The effects of operating parameters including inlet temperature, space velocity, (CH3)2S concentration, O2 concentration and catalyst size were characterized. Catalytic incineration on a mixture of (CH3)2S with CH(3)SH was also tested. The results show that the conversions of (CH3)2S increase as the inlet temperature increases and the space velocity decreases. The higher the (CH3)2S concentration is, the lower its conversion is. The O2 concentration has a positive effect on the conversion of (CH3)2S. (CH3)2S has a poisoning effect on the Pt/Al(2)O(3) catalyst, especially at lower temperatures. The conversion of (CH3)2S is significantly suppressed by the existence of CH(3)SH.
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Affiliation(s)
- H Chu
- Department of Environmental Engineering, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan.
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35
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Wen WH, Lee WT, Lin MI, Lin HC, Chiu HC, Shen YZ. Neurocutaneous melanosis with epilepsy: report of one case. Acta Paediatr Taiwan 2001; 42:108-10. [PMID: 11355063] [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: 04/16/2023]
Abstract
Neurocutaneous melanosis is a rare congenital syndrome characterized by the association of large or multiple congenital melanocytic nevi and benign or malignant melanotic tumors in the central nervous system. Patients with neurocutaneous melanosis usually have neurological symptoms early in life that progress rapidly due to the development of increased intracranial pressure or malignant melanoma. We report a 2-month-old female infant with multiple congenital melanocytic nevi and frequent seizure attacks. Magnetic resonance imaging of the brain demonstrated several regions compatible with melanotic deposits. During follow-up for one year, she had normal development and was seizure-free under the treatment of phenobarbital and valproic acid. We suggest that infants with large or multiple congenital melanocytic nevi should receive regular clinical check-up and brain imaging to exclude the possibility of central nervous system lesions.
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Affiliation(s)
- W H Wen
- Department of Pediatrics, National Taiwan University Hospital, 7, Chung-Shan South Road, Taipei 100, Taiwan
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36
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Lee WT, Sohn MK, Park SH, Ahn SK, Lee JE, Park KA. Studies on the changes of c-fos protein in spinal cord and neurotransmitter in dorsal root ganglion of the rat with an experimental peripheral neuropathy. Yonsei Med J 2001; 42:30-40. [PMID: 11293499 DOI: 10.3349/ymj.2001.42.1.30] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Animal models for human chronic pain syndromes have been developed and widely used for pain research. One of these neuropathic pain models by Kim and Chung (1992) has many advantages for operation and pain elicitation. In this neuropathic model we have examined the c-fos protein, substance P, CGRP immunoreactivity in dorsal root ganglia and dorsal horn. 50 Sprague-Dawley rats were used for this study. L5 and L6 spinal nerves were ligated tightly to produce the neuropathic pain model. After 2, 4, 8, 16, and 24 hours and 1 week of surgery, rats were anesthetized and sacrificed by perfusion. After confirmation of the roots transected by the surgery, the L5 and L6 dorsal root ganglions and spinal cord were removed and processed for immunohistochemistry. All tissue sections were immunohistochemically stained for substance P, CGRP and c-fos using the peroxidase-antiperoxidase (PAP) method. The number of immunostained substance P and CGRP dorsal root ganglion cells and c-fos immunoreactive dorsal horn cells were counted and analyzed statistically with Mann-Whitney U test. The results are as follows. The number of c-fos protein immunoreactive neurons in the superficial layer of dorsal horn were increased markedly 2 hours after operation, and gradually decreased to normal level 1 week after operation. The number of c-fos protein immunoreactive neurons in the deep layer of the dorsal horn gradually increased to a peak 24 hours after operation, then decreased to the normal level 1 week after operation. The number of substance P and CGRP immunoreactive L5 and L6 dorsal root ganglion neurons were decreased markedly 1 week after the pain model operation. In conclusion, after neuropathic pain model operation, c-fos proteins were immediately expressed in the superficial layer of spinal dorsal horn, thereafter c-fos proteins in the deep layer of spinal dorsal horn were expressed. CGRP and substance P immunoreactive neurons in DRG were decreased markedly 1 week after neuropathic pain model operation. These decrements do not coincide with the other chronic pain models, which show great increases in these pain transmitting substances. Therefore, the relationship between pain and c-fos, SP and CGRP should be investigated further.
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Affiliation(s)
- W T Lee
- Brain Research Institute and Department of Anatomy, Yonsei University College of Medicine, Seoul, Korea
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37
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Abstract
BACKGROUND Opinions vary as to whether operation should be offered patients with coronary artery fistula, particularly to those who are asymptomatic. Published studies lacked long-term follow-up data. METHODS We studied 41 patients with coronary artery fistula operated in our unit in the past 30 years with restudies including coronary angiograms in those who agreed to the investigation. RESULTS There was no operative mortality and operative morbidity was low. The mean duration of follow-up was 9.1 years and 96.9% of the patients were asymptomatic. Twenty-one patients had a coronary angiogram. The native coronary artery either remained dilated and tortuous, or more frequently had thromboses with a short proximal stump. (None of these patients had evidence of myocardial ischemia.) Four patients had demonstrable recurrence fistula but without hemodynamic disturbance. CONCLUSIONS We advocate operation for all patients with coronary artery fistulas and demonstrable shunting in view of minimal operative risks. Small asymptomatic fistulas without demonstrable shunting should be left alone. The relatively high incidence of residual or recurrent fistula makes long-term follow-up mandatory.
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Affiliation(s)
- D L Cheung
- Department of Surgery, The University of Hong Kong, Grantham Hospital, Aberdeen.
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38
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Abstract
During activation in vivo, naive CD4(+) T cells are exposed to various endogenous ligands, such as cytokines and the neurotransmitter norepinephrine (NE). To determine whether NE affects naive T cell differentiation, we used naive CD4(+) T cells sort-purified from either BALB/c or DO11.10 TCR-transgenic mouse spleens and activated these cells with either anti-CD3/anti-CD28 mAbs or APC and OVA(323-329) peptide, respectively, under Th1-promoting conditions. RT-PCR and functional assays using selective adrenergic receptor (AR) subtype antagonists showed that naive CD4(+) T cells expressed only the beta 2AR subtype to bind NE and that stimulation of this receptor generated Th1 cells that produced 2- to 4-fold more IFN-gamma. This increase was due to more IFN-gamma produced per cell upon restimulation instead of more IFN-gamma-secreting cells, as determined by IFN-gamma-specific immunofluorescence and enzyme-linked immunospot. In contrast, Th1 cell differentiation was unaffected when naive T cells were exposed to NE and activated either in the presence of a neutralizing anti-IL-12 mAb or by APC from IL-12-deficient mice. Moreover, the addition of IL-12 to the IL-12-deficient APC cultures restored the ability of NE to increase Th1 differentiation. Taken together, these results indicate that a possible link may exist between the signaling pathways used by NE and IL-12 to increase naive CD4(+) T cell differentiation to a Th1 cell.
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Affiliation(s)
- M A Swanson
- Department of Microbiology and Immunology, Loyola University Medical Center, Maywood, IL 60153, USA
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39
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Abstract
We recently showed that clones of Th1 cells, but not Th2 cells, expressed a functional beta-2-adrenergic receptor (beta2AR) and that either norepinephrine or the beta2AR agonist terbutaline stimulated this receptor to modulate the level of Th1 cytokines produced. In the present study, we show that norepinephrine and terbutaline stimulate the beta2AR to decrease the level of IL-2 produced by freshly isolated murine splenic naive CD4+ T cells from either Balb/C or DO11.10 transgenic mice and activated polyclonally with anti-CD3 and anti-CD28 mAbs. In contrast, the level of cytokines produced by primary effector Th1 and Th2 cells were unaffected when norepinephrine, terbutaline, or cAMP analogs were added at the time of restimulation. These results suggest that a diversity exists among CD4+ T-cell subsets with respect to the level of adrenergic receptor expression, responsiveness to cAMP, stage of cell differentiation, or a combination of the above.
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Affiliation(s)
- D S Ramer-Quinn
- Department of Cell Biology, Neurobiology and Anatomy, Loyola University Medical Center, 2160 South First Avenue, Maywood, Illinois 60153, USA
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40
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Abstract
The immunogenicity of soluble peptides can be improved by expression within recombinant microorganisms. The immunogenicity of a peptide expressed within a capsid protein of an attenuated coxsackievirus B4 was evaluated. The insertion site was chosen based on its antigenic structure. A foreign peptide was inserted into a region of the VP1 capsid protein that was identified as a T helper cell epitope. A recombinant virus containing ten amino acids of ovalbumin sequence was genetically stable and retained the biological and physical characteristics of the parental virus. The recombinant was able to elicit a T helper cell response against ovalbumin sequences. This study shows, for the first time, that coxsackievirus can be used as an expression vector and that insertion of heterologous peptides into an immunogenic region is a viable strategy for inducing T helper cell responses against foreign sequences. The implications of this work are that the attenuated coxsackievirus variant may be useful as a vaccine vector for expressing T helper cell epitopes that are important in inducing protective immunity.
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Affiliation(s)
- S S Halim
- Department of Biomedical Sciences, School of Public Health, State University of New York at Albany, Albany, NY 12237, USA
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41
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Abstract
The people of Hong Kong are experiencing a transition in dietary practices and lifestyle that can be observed in the fat intakes of Hong Kong children as compared with those of their counterparts on mainland China. The studies described here include 1) a longitudinal and observational dietary survey beginning with a cohort of 174 newborns and concluding with 124 children at age 7 y; 2) a biochemical study of serum lipids in relation to dietary fat intake at age 7 y; 3) a chemical fatty acid analysis and comparison of duplicate meals collected from 20 Hong Kong and 20 mainland Chinese children at age 7 y; 4) a dietary assessment of 52 lactoovovegetarian children aged 4-14 y; and 5) a comparison of the growth of all subjects with US National Center for Health Statistics standards. About 30% of the total daily energy intake of Hong Kong Chinese children aged 1-7 y was contributed by fat-much more than that in the traditional Chinese diet. Growth of the children was not impaired, including that of children on the mainland and of those lactoovovegetarians in Hong Kong whose fat intakes were lower. Mean serum cholesterol of Hong Kong Chinese children at age 7 y was 4.59 mmol/L, significantly higher than that of their counterparts on the mainland, 4.16 mmol/L. Foods consumed in Hong Kong had a significantly lower ratio of 18:2 to 14:0. Nutritional deficiency was uncommon. Chinese children in Hong Kong had a dietary fat intake that was both quantitatively and qualitatively different from the traditional Chinese diet.
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Affiliation(s)
- S S Leung
- Departments of Paediatrics and Chemical Pathology, Chinese University of Hong Kong, China.
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42
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Abstract
Herpes zoster infection has been rarely reported to cause angiitis of the central nervous system in children. We describe a 4-year, 8-month-old female with acute hemiplegia and central facial palsy 6 weeks after she had had zoster ophthalmicus. The findings of magnetic resonance angiography, the clinical picture, and a preceding history of herpes zoster ophthalmicus suggested zoster vasculitis. Herpes zoster vasculitis is thus another consideration when examining a child with acute hemiplegia and a recent herpes zoster infection.
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Affiliation(s)
- P Y Hung
- Department of Pediatrics; National Taiwan University Hospital;, Taipei, Taiwan
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43
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Kim HS, Yoon H, Minn I, Park CB, Lee WT, Zasloff M, Kim SC. Pepsin-mediated processing of the cytoplasmic histone H2A to strong antimicrobial peptide buforin I. J Immunol 2000; 165:3268-74. [PMID: 10975843 DOI: 10.4049/jimmunol.165.6.3268] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The intestinal epithelium forms a first line of innate host defense by secretion of proteins with antimicrobial activity against microbial infection. Despite the extensive studies on the antimicrobial host defense in many gastrointestinal tracts, little is known about the antimicrobial defense system of the stomach. The potent antimicrobial peptide buforin I, consisting of 39 aa, was isolated recently from the stomach tissue of an Asian toad, Bufo bufo gargarizans. In this study we examined the mechanism of buforin I production in toad stomach tissue. Buforin I is produced by the action of pepsin isozymes, named pepsin Ca and Cb, cleaving the Tyr39-Ala40 bond of histone H2A. Immunohistochemical analysis revealed that buforin I is present extracellularly on the mucosal surface, and unacetylated histone H2A, a precursor of buforin I, is localized in the cytoplasm of gastric gland cells. Furthermore, Western blot analysis showed that buforin I is also present in the gastric fluids, and immunoelectron microscopy detected localization of the unacetylated histone H2A in the cytoplasmic granules of gastric gland cells. The distinct subcellular distribution of the unacetylated histone H2A and the detection of the unacetylated buforin I both on the mucosal surface and in the lumen suggest that buforin I is produced from the cytoplasmic unacetylated histone H2A secreted into the gastric lumen and subsequently processed by pepsins. Our results indicate that buforin I along with pepsins in the vertebrate stomach may contribute to the innate host defense of the stomach against invading microorganisms.
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Affiliation(s)
- H S Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Taejon, Korea
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44
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Abstract
To investigate the mechanisms of neuronal death in neurodegeneration, in vivo localized proton magnetic resonance spectroscopy ((1)H-MRS) and diffusion-weighted MRI (DWI) were used to evaluate temporal changes in rat striata after administration of 3-nitropropionic acid. It was found that N-acetylaspartate (NAA) reduction, with nearly simultaneous evidence of striatal lesions in DWI, was preceded by a significant and progressive increase of acetate. Shortly before the NAA levels decreased to the lowest point, acetate levels peaked and began to gradually decline toward the control levels. These results suggest that acetate increase may arise from fatty acid degradation, inhibition of succinate dehydrogenase and possible NAA hydrolysis. The elevated acetate may provide a source of acetyl group for membrane repair during excitotoxic brain injury. Magn Reson Med 44:29-34, 2000.
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Affiliation(s)
- W T Lee
- Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan, Republic of China
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45
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Abstract
Severe muscle weakness in Fanconi's syndrome is rarely the result of mitochondrial cytopathy. We describe a rare case of a 9-year-old male with early onset of Fanconi's syndrome. He developed severe proximal muscle weakness exacerbated by hypokalemia and hypophosphatemia in childhood. The muscle biopsy revealed increased accumulation of abnormal mitochondria and fat droplets in histochemical stains and electron microscopy. Mitochondrial cytopathy cannot be excluded in Fanconi's syndrome with late onset of muscular impairment. Long-term follow-up of his clinical course is suggested to understand the natural history of this unusual case.
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Affiliation(s)
- L C Wang
- Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan
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46
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Arulanandam BP, Mittler JN, Lee WT, O'Toole M, Metzger DW. Neonatal administration of IL-12 enhances the protective efficacy of antiviral vaccines. J Immunol 2000; 164:3698-704. [PMID: 10725728 DOI: 10.4049/jimmunol.164.7.3698] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Neonates are highly susceptible to infectious agents and are known to display polarized expression of Th2-like cytokines and Abs. This neonatal immune bias has important implications for the development of vaccine strategies, particularly against viral infections. We now report that coadministration of IL-12 and an influenza subunit vaccine at birth enhances the protective efficacy of antiviral vaccination. Immunization and treatment with IL-12 within 24 h of birth resulted in elevated expression of IFN-gamma, IL-10, and IL-15 mRNA in the spleens of newborn mice compared with animals exposed to vaccine only. In addition, these animals showed dramatic increases in IFN-gamma-, IL-2-, and IL-4-secreting cells, and in IgG2a Ab levels upon adult challenge compared with mice primed with vaccine alone. Most importantly, animals vaccinated and simultaneously treated with IL-12 at birth displayed enhanced survival after lethal challenge with infectious influenza virus as adults compared with infected animals that had been primed with vaccine alone. This augmented protection required B cells and could be transferred to naive mice by immune serum. Collectively, these results provide evidence that administration of IL-12 to neonates induces a Th1-like response in newborns and elicits protective antiviral immune memory.
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MESH Headings
- Adjuvants, Immunologic/administration & dosage
- Animals
- Animals, Newborn/genetics
- Animals, Newborn/growth & development
- Animals, Newborn/immunology
- Antibodies, Viral/biosynthesis
- Antibodies, Viral/blood
- Antibodies, Viral/physiology
- Cytokines/biosynthesis
- Drug Therapy, Combination
- Immunoglobulin Isotypes/biosynthesis
- Immunoglobulin Isotypes/blood
- Immunoglobulin Isotypes/physiology
- Immunologic Memory
- Influenza A virus/immunology
- Influenza Vaccines/administration & dosage
- Influenza Vaccines/immunology
- Influenza Vaccines/therapeutic use
- Injections, Intraperitoneal
- Interleukin-12/administration & dosage
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Orthomyxoviridae Infections/genetics
- Orthomyxoviridae Infections/immunology
- Orthomyxoviridae Infections/prevention & control
- Th1 Cells/immunology
- Th1 Cells/metabolism
- Th2 Cells/immunology
- Th2 Cells/metabolism
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Affiliation(s)
- B P Arulanandam
- Center for Immunology and Microbial Disease, Albany Medical College, Albany, NY 12208, USA
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47
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Abstract
OBJECTIVE To study the early dietary practices in relation to growth of Hong Kong children from birth to 7 years. METHODOLOGY One hundred and seventy-three full-term Hong Kong Chinese babies were recruited at birth and were followed up for anthropometric measurements using standardized methods and dietary assessment using a combination of dietary history, 24 h recall and food frequency. At 7 years, 125 children remained in the study. RESULTS Mean (SD) birthweight was 3.3 (0.38) kg for boys and 3.1 (0.38) kg for girls. Mean (SD) weight at 7 years was 22.4 (4.2) kg for boys and 21.1 (3.7) kg for girls, and mean (SD) height was 120.3 (4.8) cm for boys and 119.8 (5.1) cm for girls. Hong Kong children were lighter and shorter than Australian children and the National Centre for Health Statistics (NCHS) references, but the magnitude is less than one standard deviation score. Mean weight and height of Hong Kong children were lower compared to Caucasian and Beijing children, with more obvious differences between 1 and 5 years. At 1 year, mean (SD) daily energy intake was 98 (24) kcal/kg/day for boys and 100 (26) kcal/kg/day for girls. By 7 years, it decreased to 82 (18) kcal/kg/day for boys and 73 (22) kcal/kg/day for girls. Between 2 to 4 years of age the energy intake of studied children were slightly lower than the Australian and Finnish children, but the protein intake was higher. Percentage of fat contributing to total daily energy intake was lower throughout at a level of 30%. Such differences in diet reflect a lower consumption of milk fat, higher consumption of meat and lower level of physical activity in Hong Kong children. Intakes of calcium, iron and vitamin C all reached 60% or above of US recommended daily allowance. CONCLUSIONS The smaller body build of Chinese compared to Caucasians cannot be explained by dietary differences. The diet of Hong Kong children is changing to one which is more Westernized with a higher consumption of animal products.
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Affiliation(s)
- S S Leung
- Department of Paediatrics, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin.
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48
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Lee WT, Shen YZ, Chang C. Neuroprotective effect of lamotrigine and MK-801 on rat brain lesions induced by 3-nitropropionic acid: evaluation by magnetic resonance imaging and in vivo proton magnetic resonance spectroscopy. Neuroscience 2000; 95:89-95. [PMID: 10619465 DOI: 10.1016/s0306-4522(99)00410-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [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: 10/18/2022]
Abstract
Magnetic resonance imaging and in vivo proton magnetic resonance spectroscopy were used to evaluate the therapeutic effect of lamotrigine and MK-801 on rat brain lesions induced by 3-nitropropionic acid. Systemic administration of 3-nitropropionic acid (15 mg/kg per day) to two-month-old Sprague-Dawley rats (n = 10 for each group) for five consecutive days induced selective striatal and hippocampal lesions and specific behavioral change. Pretreatment with lamotrigine (10 mg/kg or 20 mg/kg per day) or MK-801 (2 mg/kg per day) attenuated the lesions and behavioral change. There were no significant differences in T2 values of the striatum and hippocampus among rats pretreated with MK-801, lamotrigine (20 mg/kg) and sham controls. Significant elevations of succinate/creatine and lactate/creatine ratios and decreases of N-acetylaspartate/creatine and choline/creatine ratios were observed after 3-nitropropionic acid injections (P < 0.001). The changes were nearly prevented after pretreatment with lamotrigine (20 mg/kg). However, the N-acetylaspartate/creatine in rats pretreated with lamotrigine (10 mg/kg) (P < 0.01) and MK-801 (P < 0.05) still showed significant reduction as compared with sham controls. Thus we conclude that both lamotrigine and MK-801 are effective in attenuation of brain lesions induced by 3-nitropropionic acid. A higher dose of lamotrigine provides a better neuroprotective effect than MK-801. With a better therapeutic effect and fewer side effects, lamotrigine is more promising for potential clinical application.
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Affiliation(s)
- W T Lee
- Department of Pediatrics, College of Medicine, National Taiwan University, Taipei, Republic of China
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49
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Abstract
Congenital intracranial teratoma is a rare disease. A fetus with a congenital intracranial teratoma presenting with a disproportionately enlarged head at 27 weeks gestation is presented. Prenatal ultrasonography and fetal magnetic resonance imaging demonstrate a huge, heterogenous intracranial mass in the left supratentorial region, with the left cerebral hemisphere being compressed and flattened. The infant died of respiratory failure within 24 hours of birth at 28 weeks gestation. On postmortem examination the histologic report revealed an immature teratoma. Fetal MRI is helpful in the prenatal diagnosis and evaluation of intracranial tumor.
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Affiliation(s)
- Y H Chien
- Department of Pediatrics, National Taiwan University Hospital, Taipei
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50
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Lin YC, Lee WT, Huang SF, Young C, Wang PJ, Shen YZ. Persistent hypertransaminasemia as the presenting findings of muscular dystrophy in childhood. Acta Paediatr Taiwan 1999; 40:424-9. [PMID: 10927957] [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: 02/17/2023]
Abstract
Prolonged elevation of the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) is often attributed to hepatic diseases. However, these enzymes are also present in a variety of extrahepatic tissues, including skeletal muscle. Five children (all boys) were referred to the pediatric department of the National Taiwan University Hospital because of persistent elevation of serum aminotransferase activities. The ages of these children were between 4 months and 5.5 years. The neurological findings were all not remarkable. The initial ALT and AST values were 114-581 U/L and 183-700 U/L, respectively. Serum creatine kinase was checked first after 0 to 30 months follow-up and found to be markedly elevated (range, 10,557 U/L to 62,508 U/L). Muscle biopsies in the five cases all showed degenerating and regenerating myofibers with interstitial fibrosis. In Cases 3, 4 and 5, complete absence of dystrophin immunoreactivity was found. Genetic studies showed deletions in the DMD gene (exons 45-48 in case 2 and 49-50 in case 4). This experience indicates that occult muscle diseases should be taken into account in patients with unexplained long-lasting hypertransaminasemia and therefore measurement of serum creatine kinase activity and muscle biopsy should be done early for the correct diagnosis of muscular dystrophy.
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Affiliation(s)
- Y C Lin
- Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan
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