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Thungathurthi K, Antoniou E, Arachchi A, Tay Y, Nguyen TC, Lim J, Chouhan H, Narasimhan V, Teoh W. Surgical management of splenic flexure cancer: is there an optimal technique? A bi-national registry analysis. ANZ J Surg 2023; 93:1854-1860. [PMID: 37158233 DOI: 10.1111/ans.18469] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 03/29/2023] [Accepted: 04/09/2023] [Indexed: 05/10/2023]
Abstract
BACKGROUND Splenic flexure tumours (SFC) are uncommon and present at more advanced disease stages. The optimal surgical technique for SFC remains controversial. We sought to compare the short-term outcomes of a left hemicolectomy (LHC) versus an extended resection (subtotal colectomy, STC) for SFCs. METHODS A retrospective analysis using the Binational Colorectal Cancer Audit (BCCA) registry was performed. All patients with SFC who underwent elective or emergency surgery for a SFC between 2010 and 2021 were included. Primary outcomes included short-term inpatient complications. Secondary outcomes included survival outcomes. RESULTS Six hundred and ninety-nine patients underwent resections for SFCs. A LHC was more common, performed in 64.1%. Patients having a LHC were significantly older, with proportionally more LHCs done laparoscopically. Overall grade III/IV complications were similar between both operations. Prolonged ileus and return to theatre were significantly higher in patients undergoing a STC. On multivariate analysis, anastomotic leak and overall grade III/IV complications were not independently associated with the type of operation. There was no difference in medial survival based on type of operation. Higher tumour stage (Stage III/IV) were independently associated with worse survival. CONCLUSION Segmental and extended resections are both oncologically sound procedures for SFCs. Segmental resections are associated with lower rates of prolonged ileus.
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Affiliation(s)
| | - Ellathios Antoniou
- Department of Colorectal Surgery, Monash Health, Melbourne, Victoria, Australia
| | - Asiri Arachchi
- Department of Colorectal Surgery, Monash Health, Melbourne, Victoria, Australia
| | - Yeng Tay
- Department of Colorectal Surgery, Monash Health, Melbourne, Victoria, Australia
| | - T C Nguyen
- Department of Colorectal Surgery, Monash Health, Melbourne, Victoria, Australia
| | - James Lim
- Department of Colorectal Surgery, Monash Health, Melbourne, Victoria, Australia
| | - Hanumant Chouhan
- Department of Colorectal Surgery, Monash Health, Melbourne, Victoria, Australia
| | - Vignesh Narasimhan
- Department of Colorectal Surgery, Monash Health, Melbourne, Victoria, Australia
| | - William Teoh
- Department of Colorectal Surgery, Monash Health, Melbourne, Victoria, Australia
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2
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Cui KW, Engel L, Dundes CE, Nguyen TC, Loh KM, Dunn AR. Spatially controlled stem cell differentiation via morphogen gradients: A comparison of static and dynamic microfluidic platforms. J Vac Sci Technol A 2020; 38:033205. [PMID: 32255900 PMCID: PMC7093209 DOI: 10.1116/1.5142012#suppl] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 02/20/2020] [Accepted: 02/21/2020] [Indexed: 05/30/2023]
Abstract
The ability to harness the processes by which complex tissues arise during embryonic development would improve the ability to engineer complex tissuelike constructs in vitro-a longstanding goal of tissue engineering and regenerative medicine. In embryos, uniform populations of stem cells are exposed to spatial gradients of diffusible extracellular signaling proteins, known as morphogens. Varying levels of these signaling proteins induce stem cells to differentiate into distinct cell types at different positions along the gradient, thus creating spatially patterned tissues. Here, the authors describe two straightforward and easy-to-adopt microfluidic strategies to expose human pluripotent stem cells in vitro to spatial gradients of desired differentiation-inducing extracellular signals. Both approaches afford a high degree of control over the distribution of extracellular signals, while preserving the viability of the cultured stem cells. The first microfluidic platform is commercially available and entails static culture, whereas the second microfluidic platform requires fabrication and dynamic fluid exchange. In each platform, the authors first computationally modeled the spatial distribution of differentiation-inducing extracellular signals. Then, the authors used each platform to expose human pluripotent stem cells to a gradient of these signals (in this case, inducing a cell type known as the primitive streak), resulting in a regionalized culture with differentiated primitive streak cells predominately localized on one side and undifferentiated stem cells at the other side of the device. By combining this approach with a fluorescent reporter for differentiated cells and live-cell fluorescence imaging, the authors characterized the spatial and temporal dynamics of primitive streak differentiation within the induced signaling gradients. Microfluidic approaches to create precisely controlled morphogen gradients will add to the stem cell and developmental biology toolkit, and may eventually pave the way to create increasingly spatially patterned tissuelike constructs in vitro.
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Affiliation(s)
- Kiara W Cui
- Department of Chemical Engineering, Stanford University, Stanford, California 94305
| | - Leeya Engel
- Department of Chemical Engineering, Stanford University, Stanford, California 94305
| | - Carolyn E Dundes
- Department of Developmental Biology, Stanford Institute for Stem Cell Biology and Regenerative Medicine, Stanford University, Stanford, California 94305
| | - Tina C Nguyen
- Department of Chemical Engineering, Stanford University, Stanford, California 94305
| | - Kyle M Loh
- Department of Developmental Biology, Stanford Institute for Stem Cell Biology and Regenerative Medicine, Stanford University, Stanford, California 94305
| | - Alexander R Dunn
- Department of Chemical Engineering, Stanford University, Stanford, California 94305
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3
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Cui KW, Engel L, Dundes CE, Nguyen TC, Loh KM, Dunn AR. Spatially controlled stem cell differentiation via morphogen gradients: A comparison of static and dynamic microfluidic platforms. J Vac Sci Technol A 2020; 38:033205. [PMID: 32255900 PMCID: PMC7093209 DOI: 10.1116/1.5142012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 02/20/2020] [Accepted: 02/21/2020] [Indexed: 05/21/2023]
Abstract
The ability to harness the processes by which complex tissues arise during embryonic development would improve the ability to engineer complex tissuelike constructs in vitro-a longstanding goal of tissue engineering and regenerative medicine. In embryos, uniform populations of stem cells are exposed to spatial gradients of diffusible extracellular signaling proteins, known as morphogens. Varying levels of these signaling proteins induce stem cells to differentiate into distinct cell types at different positions along the gradient, thus creating spatially patterned tissues. Here, the authors describe two straightforward and easy-to-adopt microfluidic strategies to expose human pluripotent stem cells in vitro to spatial gradients of desired differentiation-inducing extracellular signals. Both approaches afford a high degree of control over the distribution of extracellular signals, while preserving the viability of the cultured stem cells. The first microfluidic platform is commercially available and entails static culture, whereas the second microfluidic platform requires fabrication and dynamic fluid exchange. In each platform, the authors first computationally modeled the spatial distribution of differentiation-inducing extracellular signals. Then, the authors used each platform to expose human pluripotent stem cells to a gradient of these signals (in this case, inducing a cell type known as the primitive streak), resulting in a regionalized culture with differentiated primitive streak cells predominately localized on one side and undifferentiated stem cells at the other side of the device. By combining this approach with a fluorescent reporter for differentiated cells and live-cell fluorescence imaging, the authors characterized the spatial and temporal dynamics of primitive streak differentiation within the induced signaling gradients. Microfluidic approaches to create precisely controlled morphogen gradients will add to the stem cell and developmental biology toolkit, and may eventually pave the way to create increasingly spatially patterned tissuelike constructs in vitro.
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Affiliation(s)
- Kiara W Cui
- Department of Chemical Engineering, Stanford University, Stanford, California 94305
| | - Leeya Engel
- Department of Chemical Engineering, Stanford University, Stanford, California 94305
| | - Carolyn E Dundes
- Department of Developmental Biology, Stanford Institute for Stem Cell Biology and Regenerative Medicine, Stanford University, Stanford, California 94305
| | - Tina C Nguyen
- Department of Chemical Engineering, Stanford University, Stanford, California 94305
| | - Kyle M Loh
- Department of Developmental Biology, Stanford Institute for Stem Cell Biology and Regenerative Medicine, Stanford University, Stanford, California 94305
| | - Alexander R Dunn
- Department of Chemical Engineering, Stanford University, Stanford, California 94305
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4
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Suhardja TS, Buxey K, Teoh WMK, Nguyen TC, Chouhan H. Utilisation of a modified Roeder's knot in the era of minimal invasive surgery. Tech Coloproctol 2019; 23:1101-1104. [PMID: 30976928 DOI: 10.1007/s10151-019-01986-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 04/05/2019] [Indexed: 10/27/2022]
Affiliation(s)
- T S Suhardja
- Colorectal Surgery Unit, Monash Health, Dandenong Hospital, 135 David Street, Dandenong, VIC, 3175, Australia. .,Department of Surgery, School of Clinical Sciences at Monash Health, Monash University, Clayton, VIC, 3168, Australia.
| | - K Buxey
- Colorectal Surgery Unit, Monash Health, Dandenong Hospital, 135 David Street, Dandenong, VIC, 3175, Australia
| | - W M K Teoh
- Colorectal Surgery Unit, Monash Health, Dandenong Hospital, 135 David Street, Dandenong, VIC, 3175, Australia.,Department of Surgery, School of Clinical Sciences at Monash Health, Monash University, Clayton, VIC, 3168, Australia
| | - T C Nguyen
- Colorectal Surgery Unit, Monash Health, Dandenong Hospital, 135 David Street, Dandenong, VIC, 3175, Australia
| | - H Chouhan
- Colorectal Surgery Unit, Monash Health, Dandenong Hospital, 135 David Street, Dandenong, VIC, 3175, Australia
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Abstract
Background Plasma therapies are being applied to thombotic syndromes, but there are limited controlled studies. Objective To review the evidence and the current practices for plasma therapies in thrombotic syndromes. Methods Expert-enhanced evidence-based analysis. Evidence obtained as of Dec 31, 2002 using Pub Med electronic reference library and expert-obtained library for a total of > 3,000 references obtained using the terms plasma therapy or plasma exchange or plasmapheresis or plasmafiltration or sorbents each combined with the words thrombotic syndrome or sepsis or septic shock. The authors screened the abstracts, reviewed the agreed set of papers, and compiled the recommendations. Results Plasma therapies, which alter the plasma components in patients, have been applied in thrombotic syndromes worldwide. In these patients, there is a biologic plausibility for plasma therapies since they have molecules that are prothrombotic and/or antifibrinolytic which would put them at risk for microvascular thrombosis and end-organ damage. There are respectively one randomized controlled trial (RCT) in primary thrombotic syndrome, and secondary thrombotic syndrome, which showed an improvement in mortality in applying plasma therapies (plasma exchange by centrifugation). However, there are numerous non-randomized and case series. Plasma exchange is accepted as the standard therapy for primary thrombotic syndrome as in thrombotic thrombocytopenic purpura (TTP). However, no consensus has been reached for plasma exchange in secondary thrombotic syndromes such as in sepsis, hemolytic uremic syndrome (HUS), thrombocytopenia associated multiple organ failure, TTP/HUS, s/p bone marrow or solid organ transplant, HELLP syndrome, immunologic disorders, drug exposure, or pancreatitis. Conclusions As we understand more about the pathophysiology of thrombotic syndromes, specific plasma therapies can be applied for the specific need of a particular patient population. There are sufficient preliminary data to recommend a definitive RCT to evaluate the efficacy of the different types of plasma therapies in secondary thrombotic syndromes.
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Affiliation(s)
- T C Nguyen
- Section of Critical Care, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
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6
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Peng ZY, Kiss JE, Cortese-Hasset A, Carcillo JA, Nguyen TC, Kellum JA. Plasma Filtration on Mediators of Thrombotic Microangiopathy: An in Vitro Study. Int J Artif Organs 2018; 30:401-6. [PMID: 17551903 DOI: 10.1177/039139880703000507] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objectives. Sepsis-induced thrombotic microangiopathy is successfully treated by plasma exchange therapy However, certain putative mediators of thrombotic microangiopathy may not be removed by plasma filtration. Methods. We conducted an in vitro study to determine whether plasma filtration can remove ultra-large von Willebrand factor (ULvWF) multimers and other mediators. In separate experiments, human umbilical venous endothelial cell (HUVEC) supernatant enriched with ULvWF or human whole blood was passed through a therapeutic plasma exchange (TPE 2000, PRISMA) filter and samples were taken for measurement of ULvWF, vWF ristocetin cofactor, vWF antigen and PAI-1. Results. The sieving coefficients for vWF and PAI-1 were above 0.9. The ULvWF was gradually eliminated, and nearly disappeared after four circulations. Conclusion. The TPE 2000 filter can directly remove potential mediators of sepsis-induced thrombotic microangiopathy.
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Affiliation(s)
- Z Y Peng
- Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261, USA
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7
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Lakosi L, Zsigrai J, Kocsonya A, Nguyen TC, Ramebäck H, Parsons-Moss T, Gharibyan N, Moody K. Gamma spectrometry in the ITWG CMX-4 exercise. J Radioanal Nucl Chem 2018; 315:409-416. [PMID: 29497227 PMCID: PMC5820385 DOI: 10.1007/s10967-017-5667-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Indexed: 11/09/2022]
Abstract
Low enriched uranium samples of unknown origin were analyzed by 16 laboratories in the context of a Collaborative Materials Exercise (CMX), organized by the Nuclear Forensics International Technical Working Group (ITWG). The purpose was to compare and prioritize nuclear forensic methods and techniques, and to evaluate attribution capabilities among participants. This paper gives a snapshot of the gamma spectrometric capabilities of the participating laboratories and summarizes the results achieved by gamma spectrometry.
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Affiliation(s)
- L Lakosi
- 1Nuclear Security Department, Hungarian Academy of Sciences, Centre for Energy Research, 29-33 Konkoly-Thege M., Budapest, 1121 Hungary
| | - J Zsigrai
- 2European Commission, Joint Research Centre, Directorate for Nuclear Safety and Security, P.O.Box 2340, 76125 Karlsruhe, Germany
| | - A Kocsonya
- 1Nuclear Security Department, Hungarian Academy of Sciences, Centre for Energy Research, 29-33 Konkoly-Thege M., Budapest, 1121 Hungary
| | - T C Nguyen
- 1Nuclear Security Department, Hungarian Academy of Sciences, Centre for Energy Research, 29-33 Konkoly-Thege M., Budapest, 1121 Hungary
| | - H Ramebäck
- 3Swedish Defence Research Agency, CBRN Defence and Security, Cementvägen 20, SE-901 82 Umeå, Sweden.,4Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Kemivägen 4, SE-412 58 Göteborg, Sweden
| | - T Parsons-Moss
- 5Lawrence Livermore National Laboratory, P.O. Box 808, L-186, Livermore, CA 94551 USA
| | - N Gharibyan
- 5Lawrence Livermore National Laboratory, P.O. Box 808, L-186, Livermore, CA 94551 USA
| | - K Moody
- 5Lawrence Livermore National Laboratory, P.O. Box 808, L-186, Livermore, CA 94551 USA
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Barmayehvar B, Nguyen TC, Sullivan A, Kalkat M. P271 Rates of resectable bronchiectasis and introduction of a referral framework for surgical management of bronchiectasis. Thorax 2016. [DOI: 10.1136/thoraxjnl-2016-209333.414] [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: 11/03/2022]
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9
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Huynh DH, Nguyen TC, Nguyen PD, Abeyrathne CD, Hossain MS, Evans R, Skafidas E. Environmentally friendly power generator based on moving liquid dielectric and double layer effect. Sci Rep 2016; 6:26708. [PMID: 27255577 PMCID: PMC4891717 DOI: 10.1038/srep26708] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [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: 01/30/2016] [Accepted: 05/03/2016] [Indexed: 11/24/2022] Open
Abstract
An electrostatic power generator converts mechanical energy to electrical energy by utilising the principle of variable capacitance. This change in capacitance is usually achieved by varying the gap or overlap between two parallel metallic plates. This paper proposes a novel electrostatic micro power generator where the change in capacitance is achieved by the movement of an aqueous solution of NaCl. A significant change in capacitance is achieved due to the higher than air dielectric constant of water and the Helmholtz double layer capacitor formed by ion separation at the electrode interfaces. The proposed device has significant advantages over traditional electrostatic devices which include low bias voltage and low mechanical frequency of operation. This is critical if the proposed device is to have utility in harvesting power from the environment. A figure of merit exceeding 10000(108μW)/(mm2HzV2) which is two orders of magnitude greater than previous devices, is demonstrated for a prototype operating at a bias voltage of 1.2 V and a droplet frequency of 6 Hz. Concepts are presented for large scale power harvesting.
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Affiliation(s)
- D H Huynh
- Centre for Neural Engineering, Bld 261, 203 Bouverie St, The University of Melbourne, Parkville, VIC 3010, Australia.,Department of Electrical and Electronic Engineering, Bld 193, Wilson Avenue, The University of Melbourne, Parkville, VIC 3010, Australia.,NICTA Victoria Research Laboratory, 115 Batman Street, West Melbourne VIC 3003, Australia
| | - T C Nguyen
- Centre for Neural Engineering, Bld 261, 203 Bouverie St, The University of Melbourne, Parkville, VIC 3010, Australia.,Department of Electrical and Electronic Engineering, Bld 193, Wilson Avenue, The University of Melbourne, Parkville, VIC 3010, Australia
| | - P D Nguyen
- Centre for Neural Engineering, Bld 261, 203 Bouverie St, The University of Melbourne, Parkville, VIC 3010, Australia.,Department of Electrical and Electronic Engineering, Bld 193, Wilson Avenue, The University of Melbourne, Parkville, VIC 3010, Australia.,NICTA Victoria Research Laboratory, 115 Batman Street, West Melbourne VIC 3003, Australia
| | - C D Abeyrathne
- Centre for Neural Engineering, Bld 261, 203 Bouverie St, The University of Melbourne, Parkville, VIC 3010, Australia.,Department of Electrical and Electronic Engineering, Bld 193, Wilson Avenue, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Md S Hossain
- Centre for Neural Engineering, Bld 261, 203 Bouverie St, The University of Melbourne, Parkville, VIC 3010, Australia.,Department of Electrical and Electronic Engineering, Bld 193, Wilson Avenue, The University of Melbourne, Parkville, VIC 3010, Australia.,NICTA Victoria Research Laboratory, 115 Batman Street, West Melbourne VIC 3003, Australia
| | - R Evans
- Centre for Neural Engineering, Bld 261, 203 Bouverie St, The University of Melbourne, Parkville, VIC 3010, Australia
| | - E Skafidas
- Centre for Neural Engineering, Bld 261, 203 Bouverie St, The University of Melbourne, Parkville, VIC 3010, Australia.,Department of Electrical and Electronic Engineering, Bld 193, Wilson Avenue, The University of Melbourne, Parkville, VIC 3010, Australia
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10
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Janko N, Nguyen TC, Lubel J. Looking beyond the scope: recurrent rectal bleeding in a young woman. Gut 2015; 64:1119, 1157. [PMID: 25550181 DOI: 10.1136/gutjnl-2014-308740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 12/06/2014] [Indexed: 12/08/2022]
Affiliation(s)
- Natasha Janko
- Department of Gastroenterology and Hepatology, Eastern Health, Melbourne, Victoria, Australia
| | - T C Nguyen
- Department of Colorectal Surgery, Eastern Health, Melbourne, Victoria, Australia Department of Colorectal Surgery, Monash Health, Melbourne, Victoria, Australia
| | - John Lubel
- Department of Gastroenterology and Hepatology, Eastern Health, Melbourne, Victoria, Australia Eastern Health Clinical School, Monash University, Melbourne, Victoria, Australia
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12
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Kindberg K, Carlhäll C, Karlsson M, Nguyen TC, Cheng A, Langer F, Rodriguez F, Daughters GT, Miller DC, Ingels NB. Transmural strains in the ovine left ventricular lateral wall during diastolic filling. J Biomech Eng 2009; 131:061004. [PMID: 19449958 DOI: 10.1115/1.3118774] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Rapid early diastolic left ventricular (LV) filling requires a highly compliant chamber immediately after systole, allowing inflow at low driving pressures. The transmural LV deformations associated with such filling are not completely understood. We sought to characterize regional transmural LV strains during diastole, with focus on early filling, in ovine hearts at 1 week and 8 weeks after myocardial marker implantation. In seven normal sheep hearts, 13 radiopaque markers were inserted to silhouette the LV chamber and a transmural beadset was implanted into the lateral equatorial LV wall to measure transmural strains. Four-dimensional marker dynamics were obtained 1 week and 8 weeks thereafter with biplane videofluoroscopy in closed-chest, anesthetized animals. LV transmural strains in both cardiac and fiber-sheet coordinates were studied from filling onset to the end of early filling (EOEF, 100 ms after filling onset) and at end diastole. At the 8 week study, subepicardial circumferential strain (ECC) had reached its final value already at EOEF, while longitudinal and radial strains were nearly zero at this time. Subepicardial ECC and fiber relengthening (Eff) at EOEF were reduced to 1 compared with 8 weeks after surgery (ECC:0.02+/-0.01 to 0.08+/-0.02 and Eff:0.00+/-0.01 to 0.03+/-0.01, respectively, both P<0.05). Subepicardial ECC during early LV filling was associated primarily with fiber-normal and sheet-normal shears at the 1 week study, but to all three fiber-sheet shears and fiber relengthening at the 8 week study. These changes in LV subepicardial mechanics provide a possible mechanistic basis for regional myocardial lusitropic function, and may add to our understanding of LV myocardial diastolic dysfunction.
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Affiliation(s)
- K Kindberg
- Department of Management and Engineering, Linköping University, Linköping SE-581 83, Sweden
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13
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Cullen PR, Millot P, Nguyen TC. Sheep histocompatibility antigens: a population level comparison between lymphocyte antigens previously defined in France, England and Scotland, and sheep red cell groups. Anim Blood Groups Biochem Genet 2009; 16:19-34. [PMID: 4003855 DOI: 10.1111/j.1365-2052.1985.tb01448.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A comparison test was performed to look for correlations between the three nomenclature systems for sheep histocompatibility antigens which have been previously described in France, England and Scotland. 187 French sheep from a wide variety of breeds were typed for lymphocyte antigens with antisera which detect the OLA, P and ED series of antigens; they were also tested against 387 uncharacterized French antisera. Six clusters of sera were found which showed correspondence between antigens of at least two of the three nomenclatures; five of these clusters gave high r values of 0.78-0.94. New antisera from French sheep were found which contributed to the above clusters but few additional clusters were noted. No correlation was found between any of the lymphocyte groups of antisera tested and the sheep red cell antigens which were also tested.
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14
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Abstract
Genetic linkage between the Booroola locus (Fec) and 11 sheep blood polymorphic loci (i.e. Tf, Hb, CA, OLA, and A, B, C, D, M, R, F41 red cell blood groups) was investigated in six large sire families (163 informative female offspring). The six sires tested were heterozygous for the Booroola allele (FecB) and for several genetic markers. No evidence in favour of linkage was found. Moreover, depending on the marker locus considered, linkage closer than or as close as the recombination frequency of 10-30% was excluded.
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Affiliation(s)
- T C Nguyen
- INRA-CRJ, Laboratoire des Groupes sanguins, Jouy-en-Josas, France
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15
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Abstract
Rambouillet sheep originating from Spanish Merino have been maintained in France as a small and closed flock since their importation. After 190 years of independent evolution, the flock has markedly differentiated from its Spanish parental population. The observed differences between them were characterized by the fixation in Rambouillet of the Mb and F30 alleles, which occurred in Spanish Merino with frequencies of 0.90 and 0.80 respectively (at two distinct blood group loci M and F30) and by the absence in Rambouillet of other alleles or phenogroups (at the Tf and the A, B, C blood group loci) which were observed in Spanish Merino with frequencies ranging from 0.10 to 0.28. On the basis of their phenotypic distributions at 11 blood polymorphic loci, the two populations differed significantly from each other (total chi 2 values = 352.62, 23 df, P less than 0.001). By comparing the observed magnitude of gene frequency differences between Rambouillet and Spanish Merino with the estimate of inbreeding coefficient for Rambouillet obtained from pedigrees, it appeared that the observed genetic differences could be attributed to the evolutionary change due to random drift in the small and closed flock of Rambouillet.
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Affiliation(s)
- T C Nguyen
- Département de Génétique animale, INRA-CRJ, Jouy-en-Josas, France
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16
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Abstract
Linkage between the C and I blood group loci in sheep was demonstrated by lod score analysis of data from double backcross matings. The recombination frequency between the I locus and the gene coding for the Cb red cell antigen was estimated to be 0.09 with a standard error of 0.04.
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17
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Brown CP, Nguyen TC, Moody HR, Crawford RW, Oloyede A. Assessment of common hyperelastic constitutive equations for describing normal and osteoarthritic articular cartilage. Proc Inst Mech Eng H 2009; 223:643-52. [DOI: 10.1243/09544119jeim546] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [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
With the aim of providing information for modelling joint and limb systems, widely available constitutive hyperelastic laws are evaluated in this paper for their ability to predict the mechanical responses of normal and osteoarthritic articular cartilage. Load—displacement data from mechanical indentation were obtained for normal and osteoarthritic cartilage at 0.1 s−1 and 0.025 s−1 and converted to the stress—stretch ratio. The data were then fitted to the ArrudA—Boyce, Mooney—Rivlin, neo-Hookean, Ogden, polynomial, and Yeoh hyperelastic laws in the MATLAB environment. Although each of the hyperelastic laws performed satisfactorily at the higher rate of loading, their ability to fit experimental data at the lower loading rate varied considerably. For the preferred models, coefficients were provided for stiff, soft, and average tissues to represent normal and degraded tissue at high and low loading rates. The present authors recommend the use of the Mooney—Rivlin or the Yeoh models for describing both normal and degraded articular cartilage, with the Mooney—Rivlin model providing the best compromise between accuracy and required computational power.
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Affiliation(s)
- C P Brown
- School of Engineering Systems, Queensland University of Technology, Brisbane, Australia
| | - T C Nguyen
- School of Engineering Systems, Queensland University of Technology, Brisbane, Australia
| | - H R Moody
- School of Engineering Systems, Queensland University of Technology, Brisbane, Australia
| | - R W Crawford
- School of Engineering Systems, Queensland University of Technology, Brisbane, Australia
| | - A Oloyede
- School of Engineering Systems, Queensland University of Technology, Brisbane, Australia
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Abstract
AIMS To determine the incidence of retinopathy of prematurity (ROP) based upon a national database and to identify baseline characteristics, demographic information, comorbidities, and surgical interventions. METHODS The National Inpatient Sample, a representative sample of all US hospital discharges from 1997 to 2002, was queried for all newborn infants with and without ROP. Primary outcome variables included demographics, comorbidities, hospital length of stay (LOS), and hospital charges. Multivariate logistic regression was used to predict risk factors for ROP. RESULTS 4.67 million live births were recorded during the study period. The total incidence of ROP was 0.12% overall and 7.35% for premature infants with LOS greater than 14 days. Newborns with ROP were more likely to be born at a teaching hospital and to have higher LOS and hospitalisation charges. The odds ratios for the development of ROP were greatest in infants weighing less than 1250 grams. The multivariate regression model revealed that only respiratory distress and intraventricular haemorrhage were predictive of the development of ROP and Hispanic infants were 33% more likely to develop ROP. CONCLUSION This study represents the largest cohort of newborns analysed for ROP. The multivariate analysis emphasised the role of birth weight in extended-stay infants, as well as Hispanic race, respiratory distress syndrome, and intraventricular haemorrhage.
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Affiliation(s)
- E M Lad
- Department of Ophthalmology, Stanford University School of Medicine, 1225 Crane Street, Menlo Park, CA 94025, USA
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Lejeune A, Espern A, Phung DC, Nguyen TC, Miegeville M. Mise en évidence du premier cas de microsporidiose intestinale à Enterocytozoon bieneusi chez un patient VIH positif à Hanoï, Vietnam. Med Mal Infect 2005; 35:425-6. [PMID: 16139460 DOI: 10.1016/j.medmal.2005.06.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2005] [Accepted: 06/22/2005] [Indexed: 11/23/2022]
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Pirpiris M, Wilkinson AJ, Rodda J, Nguyen TC, Baker RJ, Nattrass GR, Graham HK. Walking speed in children and young adults with neuromuscular disease: comparison between two assessment methods. J Pediatr Orthop 2003; 23:302-7. [PMID: 12724591] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Self-selected walking speed is being increasingly used as a primary outcome measure in the management of neuromuscular disease. It would be useful if the speed recorded in the gait laboratory represented the child's walking speed in the community. This study investigated the difference in self-selected walking speeds between a 10-meter walk, as measured during instrumented gait analysis, and a 10-minute walk. The authors found that self-selected walking speed during the 10-minute walk was slower than the self-selected walking speed recorded during the 10-meter walk. The former may be more representative of walking speed in the community setting. Walking speed measured during walks of 10 minutes or more should become an integral part of gait laboratory evaluation.
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Affiliation(s)
- M Pirpiris
- Hugh Williamson Gait Analysis Laboratory, Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052, Australia
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Berg M, Tran HC, Nguyen TC, Pham HV, Schertenleib R, Giger W. Arsenic contamination of groundwater and drinking water in Vietnam: a human health threat. Environ Sci Technol 2001; 35:2621-6. [PMID: 11452583 DOI: 10.1021/es010027y] [Citation(s) in RCA: 448] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This is the first publication on arsenic contamination of the Red River alluvial tract in the city of Hanoi and in the surrounding rural districts. Due to naturally occurring organic matter in the sediments, the groundwaters are anoxic and rich in iron. With an average arsenic concentration of 159 micrograms/L, the contamination levels varied from 1 to 3050 micrograms/L in rural groundwater samples from private small-scale tubewells. In a highly affected rural area, the groundwater used directly as drinking water had an average concentration of 430 micrograms/L. Analysis of raw groundwater pumped from the lower aquifer for the Hanoi water supply yielded arsenic levels of 240-320 micrograms/L in three of eight treatment plants and 37-82 micrograms/L in another five plants. Aeration and sand filtration that are applied in the treatment plants for iron removal lowered the arsenic concentrations to levels of 25-91 micrograms/L, but 50% remained above the Vietnamese Standard of 50 micrograms/L. Extracts of sediment samples from five bore cores showed a correlation of arsenic and iron contents (r2 = 0.700, n = 64). The arsenic in the sediments may be associated with iron oxyhydroxides and released to the groundwater by reductive dissolution of iron. Oxidation of sulfide phases could also release arsenic to the groundwater, but sulfur concentrations in sediments were below 1 mg/g. The high arsenic concentrations found in the tubewells (48% above 50 micrograms/L and 20% above 150 micrograms/L) indicate that several million people consuming untreated groundwater might be at a considerable risk of chronic arsenic poisoning.
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Affiliation(s)
- M Berg
- Swiss Federal Institute for Environmental Science and Technology (EAWAG), CH-8600 Dübendorf, Switzerland.
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22
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Abstract
This paper reports the blood groups and blood protein distribution in West African sheep breeds. About 100 animals of the Djallonke, Fulani and Touabire breeds were sampled for blood polymorphism analysis. Their blood groups were typed by haemolytic and agglutination reactions, and their blood proteins by starch gel electrophoresis. Almost all the loci analysed showed variability in the three breeds, with the Touabire and Fulani being closer to each other than to the Djallonke.
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Affiliation(s)
- A Missohou
- Service de Zootechnie-Alimentation, Ecole Inter-Etats des Sciences et Médecine Vétérinaires (EISMV), Dakar, Sénégal
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Missohou A, Nguyen TC, Dorchies P, Gueye A, Sow RS. Note on transferrin, hemoglobin types, and packed cell volume in Senegalese trypanotolerant Djallonke sheep. Ann N Y Acad Sci 1998; 849:209-12. [PMID: 9668466 DOI: 10.1111/j.1749-6632.1998.tb11050.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this study we examined transferrin (Tf) and hemoglobin (Hb) types and frequencies and their relationship with Packed Cell Volume (PCV), which is considered as a selection criterion for the trypanotolerance trait. Blood samples were collected from 96 sheep and were typed for Tf and Hb. The frequencies of the alleles TfA, TfB, TfC and TfD were respectively 0.276, 0.005, 0.109, and 0.609. At the locus Hb, all animals were monomorphic B. The lowest PCV value was observed in animals homozygous for TfC, while the highest value was found in heterozygous (CD) animals; however, the difference was not significant.
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Affiliation(s)
- A Missohou
- Service de Zootechnie-Alimentation, Ecole Inter-Etats des Sciences et Médecine Vétérinaires (EISMV), Dakar, Sénégal
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Nguyen AL, Nguyen TC, Van TL, Hoang MH, Nguyen S, Jonai H, Villanueva MB, Matsuda S, Sotoyama M, Sudo A. Noise levels and hearing ability of female workers in a textile factory in Vietnam. Ind Health 1998; 36:61-65. [PMID: 9473860 DOI: 10.2486/indhealth.36.61] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Noise and hearing ability profiles were determined in a textile factory in Vietnam. Noise mapping done in the weaving section showed that the noise levels exceeded the Vietnamese standard of 90 dBA by as much as 9 dBA in some areas. Audiometric tests performed on 69 female workers from the weaving section revealed that workers with more than 10 years of noise exposure had the worst hearing threshold levels at 1,000 and 4,000 Hz. Similar findings were observed for workers greater than 35 years old. The 4,000 Hz notch, suggestive of exposure to intense noise, was noted in the audiograms of 26 subjects.
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Affiliation(s)
- A L Nguyen
- National Institute of Labour Protection, Vietnam, Hanoi, Vietnam
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Nguyen TC, Solomon T, Mai XT, Nguyen TL, Nguyen TT, Wain J, To SD, Smith MD, Day NP, Le TP, Parry C, White NJ. Short courses of ofloxacin for the treatment of enteric fever. Trans R Soc Trop Med Hyg 1997; 91:347-9. [PMID: 9231214 DOI: 10.1016/s0035-9203(97)90102-4] [Citation(s) in RCA: 26] [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: 02/04/2023] Open
Abstract
Typhoid fever continues to be a major public health problem in tropical countries, exacerbated in recent years by the spread of multi-drug resistant strains of Salmonella typhi. Short treatment courses of fluoroquinolones are effective, and have the advantage of reduced cost and increased compliance, but the optimal length of treatment is unknown. In an open, randomized comparison, 107 adults with uncomplicated enteric fever (95 of whom had positive blood cultures for S. typhi and 5 for S. paratyphi) were treated with oral ofloxacin, 15 mg/kg/d for 2 d or 10 mg/kg/d for 3 d. Mean fever clearance times were the same in the 2 treatment groups (97 h). There were 7 treatment failures, one in the 2 d group and 6 in the 3 d group (P = 0.07). Three of the 5 patients infected with nalidixic acid resistant strains of S. typhi had treatment failures, compared with 4 of 90 with nalidixic acid sensitive isolates (P < 0.0001; relative risk 13.5, 95% confidence interval 4.1-43%). Treatment with ofloxacin for 2 or 3 d is equally effective in adults with uncomplicated enteric fever caused by nalidixic acid sensitive strains of S. typhi. The epidemiology and management of nalidixic acid resistent typhoid needs further investigation.
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Affiliation(s)
- T C Nguyen
- Centre for Tropical Diseases, Cho Quan Hospital, Ho Chi Minh City, Viet Nam
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Matsuda S, Nguyen AL, Jonai H, Nguyen VH, Dinh HT, Le VT, Nguyen TC, Hoang MT, Phung HD, Dang DT. Occupational exposure and chronic respiratory symptoms--a population based study in Vietnam. Ind Health 1997; 35:271-277. [PMID: 9127561 DOI: 10.2486/indhealth.35.271] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
In order to investigate the relationship between occupational exposure to dust/chemicals (toxic gases/fumes) and chronic respiratory symptoms in Vietnam, the questionnaire standardized by the American Thoracic Society was applied to 368 subjects living in Ha Thai district of Vietnam. According to the results of multiple logistic regression analyses, the odds ratios of chronic respiratory symptoms by occupational exposure are over unity, except for the relationship between chronic cough and occupational exposure to chemicals. Especially for chronic breathlessness, significantly higher odds ratios are observed among people with a history of occupational exposure to dust or chemicals: 2.925 (95% CI: 1.130-7.574) for dust, and 3.721 (95% CI: 1.412-9.803) for chemicals. As for the interaction between occupational exposure to dust and cigarette smoking, it is considered that occupational exposure leads to an increase in chronic respiratory symptoms independent of the effects of cigarette smoking.
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Affiliation(s)
- S Matsuda
- Department of Preventive Medicine and Community Health, University of Occupational and Environmental Health, Kitakyushu, Japan
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Cook KR, Murphy TD, Nguyen TC, Karpen GH. Identification of trans-acting genes necessary for centromere function in Drosophila melanogaster using centromere-defective minichromosomes. Genetics 1997; 145:737-47. [PMID: 9055083 PMCID: PMC1207858 DOI: 10.1093/genetics/145.3.737] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Deletions in the Drosophila minichromosome Dp1187 were used to investigate the genetic interactions of trans-acting genes with the centromere. Mutations in several genes known to have a role in chromosome inheritance were shown to have dominant effects on the stability of minichromosomes with partially defective centromeres. Heterozygous mutations in the ncd and klp3A kinesin-like protein genes strongly reduced the transmission of minichromosomes missing portions of the genetically defined centromere but had little effect on the transmission of minichromosomes with intact centromeres. Using this approach, ncd and klp3A were shown to require only the centromeric region of the chromosome for their roles in chromosome segregation. Increased gene dosage also affected minichromosome transmission and was used to demonstrate that the nod kinesin-like protein gene interacts genetically with the centro mere, in addition to interacting with extracentromeric regions as demonstrated previously. The results presented in this study strongly suggest that dominant genetic interactions between mutations and centromere-defective minichromosomes could be used effectively to identify novel genes necessary for centromere function.
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Affiliation(s)
- K R Cook
- Molecular Biology and Virology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, USA
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Sudo A, Nguyen AL, Jonai H, Matsuda S, Villanueva MB, Sotoyama M, Nguyen TC, Le VT, Hoang MH, Nguyen DT, Nguyen S. Effects of earplugs on catecholamine and cortisol excretion in noise-exposed textile workers. Ind Health 1996; 34:279-86. [PMID: 8768672 DOI: 10.2486/indhealth.34.279] [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] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
To investigate physiological and psychological effects of industrial noise, a survey was performed on 50 female workers exposed to machinery noise [93-100 dB(A)] (noise group) and 25 female workers in less-noisy environments [71-75 dB(A)] (control group) in a textile factory in Vietnam. Urine was collected for analysis of catecholamines and cortisol. The subjects were also asked to fill out a questionnaire. Each subject was examined over 2 working days. The workers in the noise group were asked to put earplugs in their ears during the working hours of the 2nd day. On the 1st day without earplugs, urinary excretion of catecholamines in the noise group were greater than those in the control group. Cortisol in urine showed a similar tendency. Differences in catecholamine excretion between the noise group and the control group decreased on the 2nd day when the earplugs were used for attenuation of noise level in the noise group. Frequency of subjective fatigue symptoms was lower on the 2nd day than that on the 1st day in noise group, while the control group showed almost no day-difference. The results indicate that the catecholamine response to noise in workers was reduced through the use of earplugs.
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Affiliation(s)
- A Sudo
- National Institute of Industrial Health, Kawasaki, Japan
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Wang DS, Liang YX, Nguyen TC, Le DD, Tanaka T, Ueno Y. Natural co-occurrence of Fusarium toxins and aflatoxin B1 in corn for feed in north Vietnam. Nat Toxins 1995; 3:445-9. [PMID: 8612007 DOI: 10.1002/nt.2620030607] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Natural occurrence of Fusarium mycotoxins (trichothecenes and fumonisins) and aflatoxin B1 (AFB1) were surveyed in 32 corn samples, harvested in 1993 and randomly sampled in 1994 in several districts of Hanoi, Vietnam. Corn samples were first milled into fine powder, extracted with methanol-water (3:1) and the crude extracts obtained from the same samples were used for the simultaneous analysis of the trichothecenes such as nivalenol (NIV), deoxynivalenol (DON), and T-2 toxin (T-2) by gas chromatography/mass spectrometry (GC/NS); fumonisins B1 (FB1), B2 (FB2), and B3 (FB3) by high-performance liquid chromatography (HPLC) with a flourescence detector; and AFB1 by and ELISA kit based on a monoclonal antibody. The data revealed that 14, 8, 4, 3, and 2 out of 15 corn kernel samples were positive for AFB1, FB1, FB2, FB3, and NIV with the average levels being 28, 1, 101, 276, 232, and 858 ppb, respectively, and neither DON nor T-2 were detected. As for the other 17 samples of corn powder, 13, 15, 12, 10, 4 and 2 were positive for AFB1, FB1, FB2, FB3, DON, and NIV with the average being 30, 780, 289, 176, 3, 170, and 1,365 ppb, respectively, and T-2 was not detected. Although their positive rates and levels fell in the ranges reported elsewhere, it was found for the first time that the Fusarium toxins (NIV, DON, and fumonisins) and an Aspergillus toxin (AFB1) were naturally co-contaminated in selected samples of corn produced in north Vietnam.
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Affiliation(s)
- D S Wang
- Research Institute for Biosciences, Science University of Tokyo, Japan
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Abstract
Data on allele frequencies at six red cell blood group systems and three blood protein polymorphic loci in five goat breeds are reported. Two blood proteins, albumin and carbonic anhydrase, were not found to be polymorphic. The B blood group system of goats, like its homologue in cattle and sheep, is highly complex. At least 44 B phenogroups (haplotypes) have been distinguished in this study. Based on the variation in allele frequencies between breeds, genetic distances were calculated. The distances estimated by four different methods were in close agreement with data from the history and geographic origins of the breeds examined.
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Affiliation(s)
- L Pépin
- Laboratoire des Groupes Sanguins, INRA CRJ, Jouy en Josas, France
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Montgelard C, Nguyen TC, Dubray D. Genetic variability in French populations of the Corsican mouflon (Ovis ammon musimon): analysis of 2 blood proteins and red-cell blood groups. Genet Sel Evol 1994. [PMCID: PMC2709134 DOI: 10.1186/1297-9686-26-4-303] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Lanneluc I, Drinkwater RD, Elsen JM, Hetzel DJ, Nguyen TC, Piper LR, Thimonier J, Harrison B, Gellin J. Genetic markers for the Booroola fecundity (Fec) gene in sheep. Mamm Genome 1994; 5:26-33. [PMID: 8111125 DOI: 10.1007/bf00360564] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [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: 01/28/2023]
Abstract
Animals from the Booroola line of Australian Merino sheep are characterized by a high ovulation rate that can be attributed to the presence of a codominant allele (FecB). The specific function of the gene has not been identified. Effective use of the trait within the sheep breeding industry requires one or more genetic markers that can distinguish between alternative alleles at the locus Fec. With a combination of DNA minisatellite markers and polymorphic protein markers, a cluster of seven minisatellite fragments has been identified as being linked to the Fec gene and to the ovine A blood group locus. The minisatellite fragments have been derived from multilocus probes and hence cannot be used to define the chromosomal location of the Fec gene or to serve as diagnostic markers for Fec. The derivation of cloned single locus markers from the minisatellite fragments will enable finer scale mapping of the Fec and the A blood group locus in sheep.
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Affiliation(s)
- I Lanneluc
- INRA, Laboratoire de Génétique Cellulaire, Castanet-Tolosan, France
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Nguyen TC, Osterhoff DR. Comparison between Russian and South African Karakul sheep based on blood group markers. J S Afr Vet Assoc 1992; 63:20-2. [PMID: 1533249] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Gene frequencies at 10 blood polymorphic loci have been used to compare Karakuls from Uzbekistan, Union of Soviet Socialist Republics with South African Karakuls and to evaluate the influence of local Blackhead Persian sheep on the genetic composition of South African Karakuls. The data clearly show that genetic difference between the 2 populations of Karakuls is significant. The proportion of Blackhead Persian genes in South African Karakuls is estimated to be 0.2745, to which a certain degree of gene flow from other fat-tailed sheep has possibly to be added.
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Affiliation(s)
- T C Nguyen
- Institut National de la Recherche Agronomique, Laboratoire des Groupes Sanguins, Jouyen-Josas, France
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Arnold K, Tran TH, Nguyen TC, Nguyen HP, Pham P. A randomized comparative study of artemisinine (qinghaosu) suppositories and oral quinine in acute falciparum malaria. Trans R Soc Trop Med Hyg 1990; 84:499-502. [PMID: 2091337 DOI: 10.1016/0035-9203(90)90012-4] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.3] [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: 12/30/2022] Open
Abstract
In adult patients with acute falciparum malaria in Ho Chi Minh City, Vietnam, a more rapid reduction in parasite count (50% clearance in 11.3 h) and complete clearance (41.8 h) was obtained in 32 adult patients randomly assigned to received artemisinine suppositories than was obtained with 30 patients receiving oral quinine (20.8 h and 68.1 h). There were higher degrees of resistance (RII, 3 cases; RI early, 1 case) with quinine than with artemisinine but in a subgroup of patients quinine reduced parasitaemia as rapidly as artemisinine (50% clearance 13.6 h and 10.1 h respectively). Recrudescence (RI, delayed), occurred in 16 patients receiving artemisinine compared with 6 receiving quinine. Artemisinine suppositories, because of ease of administration, efficacy, and lack of side effects or risk of overdose, have advantages for the early treatment of falciparum malaria by possibly reducing the morbidity and mortality associated with a high or sustained parasitaemia.
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Affiliation(s)
- K Arnold
- Roche Asian Research Foundation, Hong Kong
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Abstract
Evidence is presented for six genetic systems of goat red cell blood groups. The A system presently consists of one specificity, two alleles, two phenotypes (A1 and no-A1) and appears to be homologous to the A system of sheep. The B system, like its homologue in sheep, is very complex. Fourteen of 21 specificities detected in the present study, i.e. B2, B3, B4, B5, B7, B8, B9, B10, B11, B14, B15, B16, B17 and B20, belong to the B system which involves a large number of phenogroups (31 different B phenogroups identified in 26 sires). Because of their homology with sheep C and R systems, two other genetic systems of goat blood groups are named C and R respectively. Each of the two goat systems is presently a one blood group specificity, two phenotype (C12 and no-C12; R and no-R detectable on the red cells) two allele system. Two specificities, namely E6 and E18, belong to a genetic system called E in which four phenotypes are under the control of two alleles codominant and one recessive at a single locus. The F system involves but a single pair of alleles and two phenotypes (F19 and no-F19). Because of its low frequency in the goats tested, the X13 specificity remains unassigned.
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Affiliation(s)
- T C Nguyen
- Institut National de la Recherche Agronomique, Centre de Recherches de Jouy-en-Josas, France
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Luffau G, Khang J, Bouix J, Nguyen TC, Cullen P, Ricordeau G, Carrat C, Eychenne F. Resistance to experimental infections with Haemonchus contortus in Romanov sheep. Genet Sel Evol 1990. [PMCID: PMC2732645 DOI: 10.1186/1297-9686-22-2-205] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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Abstract
Studying motion in the gastrointestinal (G.I.) tract is the first step towards our goal of designing a digital algorithm for real-time noise and motion blurring reduction by temporal and spatial averaging in x-ray fluoroscopy. The present work concerns the types of motion relevant to G.I. fluoroscopy (e.g., motion of the walls of the oesophagus, the stomach, the small intestine, and the colon), and measurement of the range of velocities in different parts of the G.I. tract from tape recorded fluoroscopic sequences. The relationship between image contrast and velocity, the effects of motion on system response, and in particular the influence of these parameters on the evaluation of velocities will also be discussed.
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Affiliation(s)
- T C Nguyen
- R. B. Holmes Radiological Research Laboratory, Department of Radiology, University of Toronto, Ontario, Canada
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Lenaz MP, Nguyen TC, Hewett WJ. Leiomyosarcoma of the vulva. Conn Med 1987; 51:705-6. [PMID: 3427956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Nguyen TC. The immune response in sheep: analysis of age, sex and genetic effects on the quantitative antibody response to chicken red blood cells. Vet Immunol Immunopathol 1984; 5:237-45. [PMID: 6719821 DOI: 10.1016/0165-2427(84)90037-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The purpose of the present work was to investigate the influence of age, sex and genetic factors on the quantitative antibody response of sheep, when environmental conditions were kept under strict control. Data provided by this experiment show that sheep of 3 months old are capable of developing a measureable response to a single intravenous injection of chicken red blood cells, but the average level of haemagglutinins produced by young lambs is significantly lower than that found in adults (2 to 5 years old) of the same sex (p less than 0.001). At 7 to 8 months of age, the antibody response observed in lambs reached the adult level. There is also a tendency for a better response in females than in males, but the observed difference is small (0.6 log2) and statistically not significant. Heritability estimates clearly indicate a genetic influence on the quantitative antibody response of sheep to chicken red blood cells.
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Abstract
Blood group systems in true sheep (Ovis) provide an additional method by which phylogenetic relationships can be measured. Of the eight genetic systems of blood groups identified in domestic sheep, all appeared to have their homologue in European mouflons and at least six might have their equivalent in North American desert bighorns. The red cells of the European mouflon, which is believed to be ancestral to domestic sheep, cross-reacted with domestic sheep blood-group typing reagents much more strongly and extensively than did the red cells of desert bighorn sheep. It also was noted that all the Mexican desert bighorns tested were Da positive, but their blood factor was not observed in the Nelson desert bighorns sampled. This observation indicated that the two subspecies might differ from each other with respect to the D blood group system. Transferrin type D was observed in the mouflons, while Tfs D and E were in the desert bighorns. Hemoglobins B and AB were observed in the mouflons but only Hb B occurred in the desert bighorns. The systematic implications of blood group polymorphisms are discussed.
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Nguyen TC, Ruffet G. LES Groupes sanguins des ovins. II. Facteurs antigéniques supplémentaires dans les systèmes A, B, C et M; estimation des fréquences « allélioues » aux systèmes A, B, C, D, M et R dans les races françaises: berrichon-du-cher, ile-de-france et texel. Genetics Selection Evolution 1975; 7:145-57. [PMID: 22887506 PMCID: PMC2765855 DOI: 10.1186/1297-9686-7-2-145] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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