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Longobucco M, The Tai LX, Nguyen VH, Cimek J, Pałuba B, Buczyński R, Trippenbach M. P T-symmetry breaking in dual-core phosphate-glass photonic crystal fibers. Opt Express 2024; 32:1562-1575. [PMID: 38297705 DOI: 10.1364/oe.505927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 12/08/2023] [Indexed: 02/02/2024]
Abstract
We investigate the properties of a soft glass dual-core photonic crystal fiber for application in multicore waveguiding with balanced gain and loss. Its base material is a phosphate glass in a P2O5-Al2O3-Yb2O3-BaO-ZnO-MgO-Na2O oxide system. The separated gain and loss cores are realized with two cores with ytterbium and copper doping of the base phosphate glass. The ytterbium-doped core supports a laser (gain) activity under excitation with a pump at 1000 nm wavelength, while the CuO-doped is responsible for strong attenuation at the same wavelength. We establish conditions for an exact balance between gain and loss and investigate pulse propagation by solving a system of coupled generalized nonlinear Schrödinger equations. We predict two states of light under excitation with hyperbolic secant pulses centered at 1000 nm: 1) linear oscillation of the pulse energy between gain and loss core (P T-symmetry state), with strong power attenuation; 2) retention of the pulse in the excited gain core (broken P T-symmetry), with very modest attenuation. The optimal pulse energy levels were identified to be 100 pJ (first state) and 430 pJ (second state).
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La VH, Tran DH, Han VC, Nguyen TD, Duong VC, Nguyen VH, Tran AT, Nguyen THG, Ngo XB. Drought stress-responsive abscisic acid and salicylic acid crosstalk with the phenylpropanoid pathway in soybean seeds. Physiol Plant 2023; 175:e14050. [PMID: 37882260 DOI: 10.1111/ppl.14050] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 10/06/2023] [Accepted: 10/09/2023] [Indexed: 10/27/2023]
Abstract
Crosstalk between hormones and secondary metabolites regulates the interactions between plants and stress. However, little is known about the effects of hormone crosstalk on the concentration of flavonoids in seeds. In this study, we identified abscisic acid (ABA) as a negative regulator of flavonoid accumulation in soybean seeds under drought-stress conditions. Alterations in flavonoid accumulation at several intensities of water stress, followed by a recovery period, were measured during the soybean seed-filling stage. Low soil moisture (SM 10%) significantly decreased the total flavonoid content in seeds. The decline in flavonoid content was proportional to the severity of drought stress and was dependent on the activities of phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS), two key phenylpropanoid pathway enzymes. The expression of phenylalanine ammonia-lyase 1 (GmPAL1), chalcone isomerase 1A (GmCHI1A), and chalcone synthase 8 (GmCHS8) was associated with phenolic and flavonoid accumulation in soybean seeds of plants subjected to drought stress. Interestingly, the expression levels of GmCHS8 were highly correlated with flavonoid levels under drought stress and water recovery conditions. Cinnamic acid, which is a biosynthesis precursor shared by both phenylpropanoid metabolism and salicylic acid (SA) biosynthesis, decreased under drought stress conditions. Notably, exogenous ABA suppressed the expression of GmPAL1, which encodes the first rate-limiting enzyme in the phenylpropanoid biosynthesis pathway and affects downstream products such as SA and flavonoids. In conclusion, drought stress altered the phenylpropanoid-derived compounds, at least with regard to flavonoid and SA accumulation in seeds, which was regulated by antagonistic interactions with ABA.
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Affiliation(s)
- Van Hien La
- Center of Crop Research for Adaptation to Climate Change, Thai Nguyen University of Agriculture and Forestry, Thai Nguyen, Vietnam
| | - Dinh Ha Tran
- Center of Crop Research for Adaptation to Climate Change, Thai Nguyen University of Agriculture and Forestry, Thai Nguyen, Vietnam
- Department of Agronomy, Thai Nguyen University of Agriculture and Forestry, Thai Nguyen, Vietnam
| | - Viet-Cuong Han
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Perth, Western Australia, Australia
| | - Tien Dung Nguyen
- Department of Biotechnology and Food Technology, Thai Nguyen University of Agriculture and Forestry, Thai Nguyen, Vietnam
| | - Van Cuong Duong
- Center of Crop Research for Adaptation to Climate Change, Thai Nguyen University of Agriculture and Forestry, Thai Nguyen, Vietnam
| | - Viet Hung Nguyen
- Center of Crop Research for Adaptation to Climate Change, Thai Nguyen University of Agriculture and Forestry, Thai Nguyen, Vietnam
- Department of Agronomy, Thai Nguyen University of Agriculture and Forestry, Thai Nguyen, Vietnam
| | - Anh Tuan Tran
- Faculty of Agronomy, Vietnam National University of Agriculture, Hanoi, Vietnam
| | | | - Xuan Binh Ngo
- Department of Biotechnology and Food Technology, Thai Nguyen University of Agriculture and Forestry, Thai Nguyen, Vietnam
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Nguyen VH, Wemheuer B, Song W, Bennett H, Webster N, Thomas T. Identification, classification, and functional characterization of novel sponge-associated acidimicrobiial species. Syst Appl Microbiol 2023; 46:126426. [PMID: 37141831 DOI: 10.1016/j.syapm.2023.126426] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 04/11/2023] [Accepted: 04/23/2023] [Indexed: 05/06/2023]
Abstract
Sponges are known to harbour an exceptional diversity of uncultured microorganisms, including members of the phylum Actinobacteriota. While members of the actinobacteriotal class Actinomycetia have been studied intensively due to their potential for secondary metabolite production, the sister class of Acidimicrobiia is often more abundant in sponges. However, the taxonomy, functions, and ecological roles of sponge-associated Acidimicrobiia are largely unknown. Here, we reconstructed and characterized 22 metagenome-assembled genomes (MAGs) of Acidimicrobiia from three sponge species. These MAGs represented six novel species, belonging to five genera, four families, and two orders, which are all uncharacterized (except the order Acidimicrobiales) and for which we propose nomenclature. These six uncultured species have either only been found in sponges and/or corals and have varying degrees of specificity to their host species. Functional gene profiling indicated that these six species shared a similar potential to non-symbiotic Acidimicrobiia with respect to amino acid biosynthesis and utilization of sulfur compounds. However, sponge-associated Acidimicrobiia differed from their non-symbiotic counterparts by relying predominantly on organic rather than inorganic sources of energy, and their predicted capacity to synthesise bioactive compounds or their precursors implicated in host defence. Additionally, the species possess the genetic capacity to degrade aromatic compounds that are frequently found in sponges. The novel Acidimicrobiia may also potentially mediate host development by modulating Hedgehog signalling and by the production of serotonin, which can affect host body contractions and digestion. These results highlight unique genomic and metabolic features of six new acidimicrobiial species that potentially support a sponge-associated lifestyle.
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Affiliation(s)
- Viet Hung Nguyen
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Bernd Wemheuer
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Weizhi Song
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Holly Bennett
- Australian Institute of Marine Science, Townsville, Queensland, Australia
| | - Nicole Webster
- Australian Institute of Marine Science, Townsville, Queensland, Australia; Australian Antarctic Division, Hobart, Tasmania, Australia
| | - Torsten Thomas
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia.
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Nguyen VH, Wemheuer B, Song W, Bennett H, Palladino G, Burgsdorf I, Sizikov S, Steindler L, Webster NS, Thomas T. Functional characterization and taxonomic classification of novel gammaproteobacterial diversity in sponges. Syst Appl Microbiol 2023; 46:126401. [PMID: 36774720 DOI: 10.1016/j.syapm.2023.126401] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 01/18/2023] [Accepted: 01/22/2023] [Indexed: 01/26/2023]
Abstract
Sponges harbour exceptionally diverse microbial communities, whose members are largely uncultured. The class Gammaproteobacteria often dominates the microbial communities of various sponge species, but most of its diversity remains functional and taxonomically uncharacterised. Here we reconstructed and characterised 32 metagenome-assembled genomes (MAGs) derived from three sponge species. These MAGs represent ten novel species and belong to seven orders, of which one is new. We propose nomenclature for all these taxa. These new species comprise sponge-specific bacteria with varying levels of host specificity. Functional gene profiling highlights significant differences in metabolic capabilities across the ten species, though each also often exhibited a large degree of metabolic diversity involving various nitrogen- and sulfur-based compounds. The genomic features of the ten species suggest they have evolved to form symbiotic interaction with their hosts or are well-adapted to survive within the sponge environment. These Gammaproteobacteria are proposed to scavenge substrates from the host environment, including metabolites or cellular components of the sponge. Their diverse metabolic capabilities may allow for efficient cycling of organic matter in the sponge environment, potentially to the benefit of the host and other symbionts.
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Affiliation(s)
- Viet Hung Nguyen
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Bernd Wemheuer
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Weizhi Song
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Holly Bennett
- Australian Institute of Marine Science, Townsville, Queensland, Australia; Cawthron Institute, Nelson, New Zealand
| | - Giorgia Palladino
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia; Unit of Microbiome Science and Biotechnology, Department of Pharmacy and Biotechnology, University of Bologna, via Belmeloro 6, 40126 Bologna, Italy
| | | | | | | | - Nicole S Webster
- Australian Institute of Marine Science, Townsville, Queensland, Australia; Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia; Australian Antarctic Division, Kingston, Tasmania, Australia
| | - Torsten Thomas
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia.
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Nguyen VH, Pham NN, Truong CT, Bui DT, Nguyen HT, Truong TH. Retina-based quality assessment of tile-coded 360-degree videos. EAI Endorsed Trans Ind Net Intel Syst 2022. [DOI: 10.4108/eetinis.v9i32.1058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Nowadays, omnidirectional content, which delivers 360-degree views of scenes, is a significant aspect of Virtual Reality systems. While 360 video requires a lot of bandwidth, users only see visible tiles, therefore a large amount of bitrate can be saved without affecting the user’s experience on the service. The fact leads to current video adaptation solutions to filter out superfluous parts and extraneous bandwidth. To form a good basis for these adaptations, it is necessary to understand human’s video quality perception. In our research, we contribute to building an effective omnidirectional video database that can be applied to study the effects of the five zones of the human retina. We also design a new video quality assessment method to analyze the impacts of those zones of a 360 video according to the human retina. The proposed scheme is found to outperform 22 current objective quality measures by 11 to 31% in terms of the PCC parameter.
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Nguyen VH, Yeo YH, Zou B, Le MH, Henry L, Cheung RC, Nguyen MH. Discrepancies between actual weight, weight perception and weight loss intention amongst persons with NAFLD. J Intern Med 2021; 289:840-850. [PMID: 33340186 DOI: 10.1111/joim.13203] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 10/21/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND Currently, weight loss remains the main management strategy for NAFLD, but the weight loss intention and methods remain poorly characterized. METHODS We analysed data about the perception of weight status, intention and methods to lose weight amongst 3,822 persons with NAFLD (United States Fatty Liver Index ≥ 30) from the National Health and Nutrition Examination Survey, 2001-2014. RESULTS Only 53.9% of people with NAFLD intended to lose weight, 91.8% with perception of overweight and 8.2% with normal weight perception. Persons with perception of overweight or overweight/obese status were four times more likely to try to lose weight (adjusted odds ratios 3.9 and 4.2, respectively, both P < 0.0001). Younger age, women, higher educational level, Hispanic and blacks (versus whites) were significant independent factors associated with weight loss intention. Notably, ≤10% attended weight loss programme. Metabolic equivalent of task hours per week was significantly higher in whites who exercised to lose weight (vs. no exercise, P = 0.003) but not in other racial/ethnic groups. Interestingly, calorie intake was similar between those who dieted versus not (2056 vs. 1970 kcal/day, P = 0.11). About 30% reported ≥ 10-lb weight loss, with 50% higher odds of success for men but there was no difference by race/ethnicity. CONCLUSION Overweight or obese perception was a key driver in weight loss activities but was inconsistent with actual weight status and varied by race/ethnicity and other sociodemographic factors. Weight loss programme is under-utilized and should take in account of weight perception training and culturally appropriate approach.
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Affiliation(s)
- V H Nguyen
- From the, Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, CA, USA
| | - Y H Yeo
- From the, Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, CA, USA
| | - B Zou
- From the, Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, CA, USA
| | - M H Le
- From the, Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, CA, USA
| | - L Henry
- From the, Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, CA, USA
| | - R C Cheung
- Division of Gastroenterology and Hepatology, Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA
| | - M H Nguyen
- From the, Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, CA, USA
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Hoang VC, Jiang J, Nguyen QH, Orlov N, Le VM, Nguyen VH, Nguyen VT, Nguyen TT, Ziegler T. A new species of Vietnamophryne from Vietnam. REV SUISSE ZOOL 2021. [DOI: 10.35929/rsz.0046] [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] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Van Chung Hoang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041,
| | - Jianping Jiang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041,
| | - Quoc Huy Nguyen
- Vietnam National Museum of Nature, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Hanoi, Vietnam
| | - Nikolai Orlov
- Department of Herpetology, Zoological Institute, Russian Academy of Sciences 199034, St. Petersburg, Russia
| | - Van Manh Le
- The University of Da Nang, University of Science and Education, 459 Ton Duc Thang Road, Da Nang, Vietnam
| | | | - Vinh Thanh Nguyen
- Department of Zoology and Conservation, VNU University of Science, Vietnam National University, Hanoi, 334 Nguyen Trai Str., Thanh Xuan Dist., Hanoi, Vietnam
| | - Tao Thien Nguyen
- Vietnam National Museum of Nature, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Hanoi, Vietnam
| | - Thomas Ziegler
- AG Zoologischer Garten Köln, Riehler Strasse 173, D-50735 Cologne, Germany
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Nguyen TAH, Ngo HH, Guo WS, Nguyen TT, Vu ND, Soda S, Nguyen THH, Nguyen MK, Tran TVH, Dang TT, Nguyen VH, Cao TH. White hard clam (Meretrix lyrata) shells as novel filter media to augment the phosphorus removal from wastewater. Sci Total Environ 2020; 741:140483. [PMID: 32615439 DOI: 10.1016/j.scitotenv.2020.140483] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [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: 05/13/2020] [Revised: 06/20/2020] [Accepted: 06/22/2020] [Indexed: 06/11/2023]
Abstract
It is well recognized that filter media play a crucial role in constructed wetlands (CWs) for decontamination of phosphorus (P)-rich wastewater. This study investigates the suitability of raw white hard clam shells (WHC) and white hard clam shells thermally modified at 800 °C (WHC-M800) as potential media to enhance P treatment performance in CWs. The results indicated that both WHC and WHC-M800 displayed appropriate physicochemical properties, such as high porosity, excellent hydraulic conductivity, and rich Ca content. WHC-M800 exhibited a superior P adsorption capacity (38.7 mg/g) to WHC (12.8 mg/g). However, the practical utilization of WHC-M800 as filter media in CWs may be compromised, due to certain limitations, for example: extremely high pH values in the post-adsorption solutions; high weight losses during calcination and adsorption processes; low mechanical strength; and intensive energy consumption. In contrast, the WHC demonstrated significant advantages of reasonably high P adsorption capacity, locally abundant availability, low cost, and marginal side effects. The fractionation of inorganic P of WHC and WHC-M800 revealed that Ca-bounded P was the most dominant binding form, followed by loosely bound P, Fe-P, occluded P, and Al-P. The present study demonstrates that recycling of WHC shells as a potential substrate in CWs provides a feasible method for upgrading P removal in CWs. Additionally, it helps to reduce waste WHC shells in a simple, cheap, and eco-friendly way, thus can double environmental benefits.
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Affiliation(s)
- T A H Nguyen
- Vietnam Japan University (VJU), Vietnam National University, Hanoi (VNU), Luu Huu Phuoc St., Nam Tu Liem Dist., Hanoi 101000, Vietnam
| | - H H Ngo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology, Sydney, Broadway NSW 2007, Australia.
| | - W S Guo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology, Sydney, Broadway NSW 2007, Australia
| | - T T Nguyen
- Graduate School of Science and Engineering, Ritsumeikan University (RITs), Biwako-Kusatsu Campus, Shiga 525-8577, Japan
| | - N D Vu
- University of Science (HUS), Vietnam National University, Hanoi (VNU), 334 Nguyen Trai Rd., Thanh Xuan Dist., Hanoi 120106, Vietnam; Center for Environmental Technology and Sustainable Development, VNU University of Science (VNU-HUS), 334 Nguyen Trai Rd., Thanh Xuan Trung Ward, Thanh Xuan Dist., Hanoi 120106, Vietnam
| | - S Soda
- Graduate School of Science and Engineering, Ritsumeikan University (RITs), Biwako-Kusatsu Campus, Shiga 525-8577, Japan
| | - T H H Nguyen
- University of Science (HUS), Vietnam National University, Hanoi (VNU), 334 Nguyen Trai Rd., Thanh Xuan Dist., Hanoi 120106, Vietnam
| | - M K Nguyen
- University of Science (HUS), Vietnam National University, Hanoi (VNU), 334 Nguyen Trai Rd., Thanh Xuan Dist., Hanoi 120106, Vietnam
| | - T V H Tran
- Vietnam Japan University (VJU), Vietnam National University, Hanoi (VNU), Luu Huu Phuoc St., Nam Tu Liem Dist., Hanoi 101000, Vietnam
| | - T T Dang
- Vietnam Japan University (VJU), Vietnam National University, Hanoi (VNU), Luu Huu Phuoc St., Nam Tu Liem Dist., Hanoi 101000, Vietnam
| | - V H Nguyen
- Research Center for Environmental Monitoring and Modeling, VNU University of Science (VNU-HUS), 334 Nguyen Trai Rd., Thanh Xuan Trung Ward, Thanh Xuan Dist., Hanoi 120106, Vietnam
| | - T H Cao
- Vietnam Japan University (VJU), Vietnam National University, Hanoi (VNU), Luu Huu Phuoc St., Nam Tu Liem Dist., Hanoi 101000, Vietnam; Center for Environmental Technology and Sustainable Development, VNU University of Science (VNU-HUS), 334 Nguyen Trai Rd., Thanh Xuan Trung Ward, Thanh Xuan Dist., Hanoi 120106, Vietnam
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9
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Nguyen VH, The Tai LX, Bugar I, Longobucco M, Buczyński R, Malomed BA, Trippenbach M. Reversible ultrafast soliton switching in dual-core highly nonlinear optical fibers. Opt Lett 2020; 45:5221-5224. [PMID: 32932495 DOI: 10.1364/ol.404039] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 08/19/2020] [Indexed: 06/11/2023]
Abstract
We experimentally investigate a nonlinear switching mechanism in a dual-core highly nonlinear optical fiber. We focus the input stream of femtosecond pulses on one core only, to identify transitions between inter-core oscillations, self-trapping in the cross core, and self-trapping of the pulse in the straight core. A model based on the system of coupled nonlinear Schrödinger equations provides surprisingly good agreement with the experimental findings.
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10
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Zou B, Yeo YH, Nguyen VH, Cheung R, Ingelsson E, Nguyen MH. Prevalence, characteristics and mortality outcomes of obese, nonobese and lean NAFLD in the United States, 1999-2016. J Intern Med 2020; 288:139-151. [PMID: 32319718 DOI: 10.1111/joim.13069] [Citation(s) in RCA: 136] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 03/08/2020] [Accepted: 03/27/2020] [Indexed: 12/15/2022]
Abstract
BACKGROUND Updated prevalence and outcome data for nonobese NAFLD for the multi-ethnic US population is limited. OBJECTIVES We aimed to investigate the prevalence, clinical characteristics and mortality of obese and nonobese individuals with NAFLD in the United Sates. METHODS A retrospective study was conducted using the 1999-2016 NHANES databases. We determined hazard ratio stratified by obesity status in NAFLD individuals using Cox regression and log-rank test. RESULTS Overall NAFLD prevalence was 32.3%: 22.7% were obese and 9.6% were nonobese, with increasing trend over time for obese NAFLD, but not nonobese NAFLD. Amongst those with NAFLD, 29.7% (95% CI: 27.8%-31.7%) were nonobese, of which 13.6% had lean NAFLD. Nonobese NAFLD was more common in older (40.9% if ≥ 65 vs. 24.2% if < 65 years), male (34.0% vs. 24.2%) and foreign-born Asian people (39.8% vs. 11.4%) and uncommon in black (11.5% vs 30-35% in other ethnicities, P < 0.001). Metabolic comorbidities were common in nonobese NAFLD individuals who also had more advanced fibrosis. Nonobese NAFLD individuals had higher 15-year cumulative all-cause mortality (51.7%) than obese NAFLD (27.2%) and non-NAFLD (20.7%) (P < 0.001). However, DM and fibrosis, but neither obese nor nonobese NAFLD compared to non-NAFLD was independently associated with higher mortality. CONCLUSION Nonobese NAFLD makes up about one-third of the NAFLD in the United States (even higher in older, male and foreign-born individuals) and carries higher mortality than obese NAFLD. Screening for NAFLD should be considered in high-risk groups even in the absence of obesity.
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Affiliation(s)
- B Zou
- Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, CA, USA
| | - Y H Yeo
- Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, CA, USA
| | - V H Nguyen
- Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, CA, USA
| | - R Cheung
- Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, CA, USA.,Division of Gastroenterology and Hepatology, Veterans Affairs Medical Center, Palo Alto, CA, USA
| | - E Ingelsson
- Department of Medicine, Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, CA, USA.,Stanford Cardiovascular Institute, Stanford University, Stanford, CA, USA.,Stanford Diabetes Research Center, Stanford University, Stanford, CA, USA
| | - M H Nguyen
- Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, CA, USA
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11
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Fox GJ, Nguyen VN, Dinh NS, Nghiem LPH, Le TNA, Nguyen TA, Nguyen BH, Nguyen HD, Tran NB, Nguyen TL, Le TN, Nguyen VH, Phan TL, Nguyen KC, Ho J, Pham DC, Britton WJ, Bestrashniy JRBM, Marks GB. Post-treatment Mortality Among Patients With Tuberculosis: A Prospective Cohort Study of 10 964 Patients in Vietnam. Clin Infect Dis 2020; 68:1359-1366. [PMID: 30202910 DOI: 10.1093/cid/ciy665] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Accepted: 08/14/2018] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Tuberculosis is the leading infectious cause of death. Steep reductions in tuberculosis-related mortality are required to realize the World Health Organization's "End Tuberculosis Strategy." However, accurate mortality estimates are lacking in many countries, particularly following discharge from care. This study aimed to establish the mortality rate among patients with pulmonary tuberculosis in Vietnam and to quantify the excess mortality in this population. METHODS We conducted a prospective cohort study among adult patients treated for smear-positive pulmonary tuberculosis in 70 clinics across Vietnam. People living in the same households were recruited as controls. Participants were re-interviewed and their survival was established at least 2 years after their treatment with an 8-month standardized regimen. The presence of relapse was established by linking identifying data on patients and controls to clinic registries. Verbal autopsies were performed. The cumulative mortality among patients was compared to that among a control population, adjusting for age and gender. RESULTS We enrolled 10964 patients and 25707 household controls. Among enrolled tuberculosis patients, 9% of patients died within a median follow-up period of 2.9 years: 342 (3.1%) during treatment and 637 (5.8%) after discharge. The standardized mortality ratio was 4.0 (95% confidence interval 3.7-4.2) among patients with tuberculosis, compared to the control population. Tuberculosis was the likely cause of death for 44.7% of these deceased patients. CONCLUSIONS Patients treated for tuberculosis had a markedly elevated risk of death, particularly in the post-treatment period. Interventions to reduce tuberculosis mortality must enhance the early detection of drug-resistance, improve treatment effectiveness, and address non-communicable diseases.
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Affiliation(s)
- G J Fox
- Faculty of Medicine and Health, University of Sydney, Australia.,Woolcock Institute of Medical Research, Glebe, New South Wales, Australia
| | - V N Nguyen
- National Lung Hospital, Ba Dinh, Hanoi, Vietnam
| | - N S Dinh
- National Lung Hospital, Ba Dinh, Hanoi, Vietnam
| | - L P H Nghiem
- Woolcock Institute of Medical Research, Glebe, New South Wales, Australia
| | - T N A Le
- National Lung Hospital, Ba Dinh, Hanoi, Vietnam
| | - T A Nguyen
- Woolcock Institute of Medical Research, Glebe, New South Wales, Australia
| | - B H Nguyen
- National Lung Hospital, Ba Dinh, Hanoi, Vietnam.,Centre for Operational Research, International Union Against Tuberculosis and Lung Disease, Paris, France
| | - H D Nguyen
- Pham Ngoc Thach Hospital, Ho Chi Minh City, Vietnam
| | - N B Tran
- Woolcock Institute of Medical Research, Glebe, New South Wales, Australia
| | - T L Nguyen
- Woolcock Institute of Medical Research, Glebe, New South Wales, Australia
| | - T N Le
- Woolcock Institute of Medical Research, Glebe, New South Wales, Australia
| | - V H Nguyen
- Woolcock Institute of Medical Research, Glebe, New South Wales, Australia
| | - T L Phan
- Woolcock Institute of Medical Research, Glebe, New South Wales, Australia
| | - K C Nguyen
- National Lung Hospital, Ba Dinh, Hanoi, Vietnam.,Hanoi Medical University, Hanoi, Vietnam
| | - J Ho
- Faculty of Medicine and Health, University of Sydney, Australia
| | - D C Pham
- Woolcock Institute of Medical Research, Glebe, New South Wales, Australia
| | - W J Britton
- Faculty of Medicine and Health, University of Sydney, Australia.,Centenary Institute of Cancer Medicine and Cell Biology, University of Sydney, Camperdown, New South Wales, Australia
| | | | - G B Marks
- Woolcock Institute of Medical Research, Glebe, New South Wales, Australia.,South Western Sydney Clinical School, University of New South Wales, Kensington, New South Wales, Australia
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Atopkin DM, Besprozvannykh VV, Ha DN, Nguyen VH, Nguyen VT. New species and new genus of Pseudohaploporinae (Digenea): Pseudohaploporus pusitestis sp. n. and Parahaploporus elegantus n. g., sp. n. (Digenea: Pseudohaploporinae) from Vietnamese mullet fish. Parasitol Int 2019; 75:102023. [PMID: 31715266 DOI: 10.1016/j.parint.2019.102023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [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: 05/27/2019] [Revised: 11/04/2019] [Accepted: 11/07/2019] [Indexed: 11/17/2022]
Abstract
Two new species of Pseudohaploporinae, Pseudohaploporus pusitestis sp. n. and Parahaploporus elegantus n. g., sp. n., are described from intestines of the Vietnamese mullet fish Moolgarda seheli and Osteomugil cunnesius, respectively. Pseudohaploporus pusitestis sp. n. differs from two known Pseudohaploporus species, P. vietnamensis and P. planiliza, by the absence of a diverticulate hermaphroditic duct and muscular sphincters at the proximal end of the hermaphroditic sac. Metrically, P. pusitestis sp. n. is close to P. vietnamensis and differs from this species and from P. planilizum by lower maximum sizes of most parameters. Parahaploporus elegantus n. g., sp. differs from representatives of Pseudohaploporus by the presence of a single testis and the armament of hermaphroditic duct and is morphologically close to trematodes of the genus Haploporus. However, P. elegantus n. g differs from all known Haploporus species from mugilids of the Indo-West Pacific by the structure of the armament of the hermaphroditic duct and also by size of body, organs and eggs. The validity of designating two new species and a new genus of trematodes is supported by ITS and 28S rDNA sequence data. Phylogenetic reconstructions showed that the new trematodes belong to the Pseudohaploporinae, which formed a well-supported cluster within the monophyletic Haploporidae.
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Affiliation(s)
- D M Atopkin
- Federal Scientific Center of East Asia Terrestrial Biodiversity, Far Eastern Branch of Russian Academy of Sciences, 690022 Vladivostok, Russia; Department of Cell Biology and Genetics, Far Eastern Federal University, 690051, Ajax-10 str, Vladivostok, Russia.
| | - V V Besprozvannykh
- Federal Scientific Center of East Asia Terrestrial Biodiversity, Far Eastern Branch of Russian Academy of Sciences, 690022 Vladivostok, Russia
| | - D N Ha
- Institute of Ecology and Biological Resources, Vietnamese Academy of Sciences and Technology, Hanoi, Viet Nam
| | - V H Nguyen
- Institute of Ecology and Biological Resources, Vietnamese Academy of Sciences and Technology, Hanoi, Viet Nam
| | - V T Nguyen
- Hai Duong Medical Technical University, Hanoi, Viet Nam
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Morisot F, Nguyen VH, Montemont C, Maindron T, Muñoz-Rojas D, Mouis M, Langlet M, Ternon C. Al 2O 3, Al doped ZnO and SnO 2 encapsulation of randomly oriented ZnO nanowire networks for high performance and stable electrical devices. Nanotechnology 2019; 30:385202. [PMID: 31212261 DOI: 10.1088/1361-6528/ab2aa5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Two-dimensional randomly oriented nanowire (NW) networks, also called nanonets (NNs), have remarkable advantages including low-cost integration, good reproducibility and high sensitivity, which make them a promising material for electronic devices. With this work, we focus on the study of ZnO NNs as channel materials in field effect transistors (FETs). In our process, ZnO NWs were assembled in NNs by the liquid filtration method and were integrated in transistors, with the bottom-gate configuration, using simple technological steps. Non-encapsulated devices exhibited state of the art performances but their stability toward air exposure was poor. Using a proper encapsulation of the nanonets, with cheap, abundant and non-toxic oxides, we demonstrate our ability not only to stabilize their electrical properties, but also to enhance performance to values never reach before for ZnO NW-based transistors. Our best FETs exhibit a low Off-current while maintaining a very good On-current, which results in a I on/I off ratio exceeding 106 for a drain voltage of 5 V. The behavior of these ZnO NN-based FETs was studied for three different encapsulation materials, alumina (Al2O3), tin oxide (SnO2) and Al-doped ZnO (AZO). These results prove that ZnO NNs are highly promising materials for an easy and low-cost integration into FETs.
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Affiliation(s)
- F Morisot
- Univ. Grenoble Alpes, CNRS, Grenoble INP*, LMGP, F-38000 Grenoble, France. Univ. Grenoble Alpes, CNRS, Grenoble INP*, IMEP-LaHC, F-38000 Grenoble, France
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Nguyen TNT, Ha DV, Do TNN, Nguyen VH, Ngo XT, Phan VH, Nguyen ND, Bui QH. Air pollution monitoring network using low-cost sensors, a case study in Hanoi, Vietnam. ACTA ACUST UNITED AC 2019. [DOI: 10.1088/1755-1315/266/1/012017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Maß TWW, Nguyen VH, Schnakenberg U, Taubner T. Tailoring grating strip widths for optimizing infrared absorption signals of an adsorbed molecular monolayer. Opt Express 2019; 27:10524-10532. [PMID: 31052910 DOI: 10.1364/oe.27.010524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 02/26/2019] [Indexed: 06/09/2023]
Abstract
Metal structures with resonances in the mid-infrared spectral range enable an increased sensitivity for detecting molecular vibrational signals. 1D gold strip gratings have already proven potential in surface-enhanced infrared absorption (SEIRA) experiments, as grating resonances and local electric field enhancement can be spectrally tuned by changing the grating period. Here, we identify the grating strip width as another important design parameter, which is investigated for further optimization of molecular absorption signal enhancement in SEIRA experiments. Previous literature used gratings to increase light absorption in relatively thick polymer layers. Here, we demonstrate the capability of gold strip gratings fabricated on a CaF2 substrate to enhance the CH2 vibrational modes of a thiol-based monolayer of MHDA. An optimal choice of the strip width w = 1.33 μm enables a maximum vibrational signal enhancement factor of around 84, when normalized to microscopic GIR measurements of an MHDA monolayer on an extended gold surface. Numerical simulations demonstrate the broadband local field enhancement of gold strip gratings, which are suitable for enhancing multiple vibrational modes in a large hot-spot volume.
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Bestrashniy JRBM, Nguyen VN, Nguyen TL, Pham TL, Nguyen TA, Pham DC, Nghiem LPH, Le TNA, Nguyen BH, Nguyen KC, Nguyen HD, Buu TN, Le TN, Nguyen VH, Dinh NS, Britton WJ, Marks GB, Fox GJ. Recurrence of tuberculosis among patients following treatment completion in eight provinces of Vietnam: A nested case-control study. Int J Infect Dis 2018; 74:31-37. [PMID: 29944930 DOI: 10.1016/j.ijid.2018.06.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 06/06/2018] [Accepted: 06/17/2018] [Indexed: 10/28/2022] Open
Abstract
BACKGROUND Patients completing treatment for tuberculosis (TB) in high-prevalence settings face a risk of developing recurrent disease. This has important consequences for public health, given its association with drug resistance and a poor prognosis. Previous research has implicated individual factors such as smoking, alcohol use, HIV, poor treatment adherence, and drug resistant disease as risk factors for recurrence. However, little is known about how these factors co-act to produce recurrent disease. Furthermore, perhaps factors related to the index disease means higher burden/low resource settings may be more prone to recurrent disease that could be preventable. METHODS We conducted a case-control study nested within a cohort of consecutively enrolled adults who were being treated for smear positive pulmonary TB in 70 randomly selected district clinics in Vietnam. Cases were patients with recurrent TB, identified by follow-up from the parent cohort study. Controls were selected from the cohort by random sampling. Information on demographic, clinical and disease-related characteristics was obtained by interview. Treatment information was extracted from clinic registries. Logistic regression, with stepwise selection, was used to develop a fully adjusted model for the odds of recurrence of TB. RESULTS We recruited 10,964 patients between October 2010 and July 2013. Median follow-up was 988 days. At the end of follow-up, 505 patients (4.7%) with recurrence were identified as cases and 630 other patients were randomly selected as controls. Predictors of recurrence included multidrug-resistant (MDR)-TB (adjusted odds ratio 79.6; 95% CI: 25.1-252.0), self-reported prior TB therapy (aOR=2.5; 95% CI: 1.7-3.5), and incomplete adherence (aOR=1.9; 95% CI 1.1-3.1). CONCLUSIONS Index disease treatment history is a leading determinant of relapse among patients with TB in Vietnam. Further research is required to identify interventions that will reduce the risk of recurrent disease and enhance its early detection within high-risk populations.
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Affiliation(s)
| | | | - Thi Loi Nguyen
- Woolcock Institute of Medical Research, Glebe, NSW, 2037, Australia
| | - Thi Lieu Pham
- Woolcock Institute of Medical Research, Glebe, NSW, 2037, Australia
| | - Thu Anh Nguyen
- Woolcock Institute of Medical Research, Glebe, NSW, 2037, Australia
| | - Duc Cuong Pham
- Woolcock Institute of Medical Research, Glebe, NSW, 2037, Australia
| | | | | | - Binh Hoa Nguyen
- National Lung Hospital, Ba Dinh, Hanoi, Vietnam; Centre for Operational Research, International Union Against Tuberculosis and Lung Disease, Paris, France
| | - Kim Cuong Nguyen
- National Lung Hospital, Ba Dinh, Hanoi, Vietnam; Hanoi Medical University, Hanoi, Vietnam
| | | | - Tran Ngoc Buu
- Woolcock Institute of Medical Research, Glebe, NSW, 2037, Australia
| | - Thi Nhung Le
- Woolcock Institute of Medical Research, Glebe, NSW, 2037, Australia
| | - Viet Hung Nguyen
- Woolcock Institute of Medical Research, Glebe, NSW, 2037, Australia
| | | | - Warwick John Britton
- Centenary Institute of Cancer Medicine and Cell Biology, University of Sydney, Camperdown, NSW, 2050, Australia; Faculty of Medicine and Health, University of Sydney, NSW, 2006, Australia
| | - Guy Barrington Marks
- Woolcock Institute of Medical Research, Glebe, NSW, 2037, Australia; South Western Sydney Clinical School, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Greg James Fox
- Woolcock Institute of Medical Research, Glebe, NSW, 2037, Australia; Faculty of Medicine and Health, University of Sydney, NSW, 2006, Australia.
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Nguyen VH, Kalal M, Suk H, Janulewicz KA. Interferometric analysis of sub-nanosecond laser-induced optical breakdown dynamics in the bulk of fused-silica glass. Opt Express 2018; 26:14999-15008. [PMID: 30114753 DOI: 10.1364/oe.26.014999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 05/05/2018] [Indexed: 06/08/2023]
Abstract
Dynamics of laser-induced optical breakdown in the bulk of fused-silica glass irradiated by a sub-nanosecond laser pulse at a wavelength of 790 nm with a fluence of 522 J/cm2 was studied by the femtosecond time-resolved complex interferometry in Nomarski arrangement utilising a Fresnel bi-prism. Evolution of the plasma channel and the development of the free electron density were in focus of the investigation. The measured ultimate length of the plasma channel was equal to 30 μm and almost doubled the length estimated within the moving breakdown model. The history of the transient electron density distribution in the plasma was reconstructed from the phase shift maps using the inverse Abel transform and it revealed further deviation from this model. The core of the plasma channel exhibited at the last stages of the development a considerable level of the electron density up to 2.4×1020 cm-3. The signature of the pre-breakdown phase has been identified as radiation caused by ionization-released electrons interacting with ions and has been demonstrated in solids for the first time in this way. Origin of the discrepancy between the theoretical prediction of the moving breakdown model and the measured values of the channel length is discussed as well.
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Affiliation(s)
- V H Nguyen
- Public Health Program, Department of Health Sciences, School of Health Professions, University of Missouri, Columbia, MO, USA.
- Community Health Program, Nursing Department, School of Natural Sciences & Mathematics, Columbia College of Missouri, Columbia, MO, USA.
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Nguyen VH, Nguyen VL, Hoang NS, Do TK. Effect of cell membrane permeability protein on porcine oocyte vitrification. Cryo Letters 2016; 37:103-109. [PMID: 27224521] [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: 06/05/2023]
Abstract
BACKGROUND The discovery of proteins with inherent cell membrane-translocating activity will expand our ability to study and manipulate various intracellular processes in living systems. OBJECTIVE We investigated the effect of TAT-EGFP (trans-activator of transcription-enhanced green fluorescent protein) intra-cellular delivery on the survival and development of mature porcine oocytes after cryopreservasion. MATERIALS AND METHODS Cumulus-oocyte complexes (COCs) collected from follicles 3 to 6 mm in diameter in abattoir-derived oocytesries of prepubertal gilts were on vitro matured (IVM). After IVM, the oocytes were used for TAT-EGFP delivery test and cryopreservation with and without TAT-EGFP supplementation. Oocyte viability was assayed by staining with fluorescein diacetate. Live oocytes were parthened and cultured in vitro, to assess their ability to be activated and to therefore develop. RESULTS The results show that the TAT-EGFP was well delivered into the nuclear of the Hela cell and oocytes also. In the medium toxic test, the proportion of viable oocytes in seven groups showed no significance. In vitrification experiments, the viability of oocytes in group supplemented with TAT-EGFP was significantly higher than that in the without TAT-EGFP group and the control groups (27.7%, 90.4%, and 100%, respectively). Among the three groups, the developmental abilities of oocytes in the supplement TAT-EGFP, EGFP and Control groups revealed that the vitrified group had a significantly reduced ability to undergo first cleavage (34.4%, 63.3%, and 69.0%, respectively). CONCLUSION the supplement of TAT-EGFP protein into vitrification medium does not affect the viability of the oocytes whereas it improved the viability and developmental potential of oocytes after it was vitrified.
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Affiliation(s)
- V H Nguyen
- Laboratory of Embryo Biotechnology, Institute of Biotechnology, Vietnam Academy of Science and Technology, Hanoi, Vietnam.
| | - V L Nguyen
- Laboratory of Embryo Biotechnology, Institute of Biotechnology, Vietnam Academy of Science and Technology, Hanoi, Vietnam
| | - N S Hoang
- Department of Animal Biotechnology, Institute of Tropical Biology, Vietnam Academy of Science and Technology, Ho Chi Minh City, Vietnam
| | - T K Do
- Fisheries College, Tuson District, Bacninh Province, Vietnam
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Mustafa MZ, Nguyen VH, Le Naour F, De Martin E, Beleoken E, Guettier C, Johanet C, Samuel D, Duclos-Vallee JC, Ballot E. Autoantibody signatures defined by serological proteome analysis in sera from patients with cholangiocarcinoma. J Transl Med 2016; 14:17. [PMID: 26774260 PMCID: PMC4715332 DOI: 10.1186/s12967-015-0751-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 12/08/2015] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND The challenging diagnosis and poor prognosis of cholangiocarcinoma require the determination of biomarkers. Autoantibodies could be used in the clinic as diagnostic markers for the early detection of tumours. By proteomic approaches, several autoantibodies were proposed as potential markers. We tried in this study, to perform a serological proteome analysis, using various antigenic substrates, including tumours and human liver. METHODS Sera from patients (n = 13) and healthy donors (n = 10) were probed on immunoblots performed using 2-dimensionally separated proteins from cholangiocarcinoma cell lines (CCLP1 and CCSW1), from the liver of healthy subject and interestingly, from tumour and adjacent non-tumour liver tissues from five patients with cholangiocarcinoma and tested with their corresponding serum. Spots of interest were identified using mass spectrometry and classified according gene ontology analysis. RESULTS A comparison of the whole immunoblotting patterns given by cholangiocarcinoma sera against those obtained with normal control sera enabled the definition of 862 spots. Forty-five different proteins were further analysed, corresponding to (1) spots stained with more than four of 13 (30 %) sera tested with the CCLP1 or the CCSW1 cell line and with the normal liver, and (2) to spots immunoreactive with at least two of the five sera probed with their tumour and non-tumour counter-part of cholangiocarcinoma. Immunoreactive proteins with catalytic activity as molecular function were detected at rates of 93 and 64 % in liver from healthy subjects or cholangiocarcinoma non-tumour tissues respectively, compared to 43, 33, 33 % in tumour tissues, or CCSW1 and CCLP1 cell lines. A second pattern was represented by structural proteins with rates of 7 and 7 % in normal liver or non-tumour tissues compared to 14, 33 and 67 % in tumour tissue, CCSW1 or CCLP1 cell lines. Proteins with a binding function were detected at rates of 7 % in non-tumour tissue and 14 % in tumour tissue. Using the extracted tumour tissue, serotransferrin was targeted by all cholangiocarcinoma-related sera. CONCLUSIONS Immunological patterns depended on the type of antigen substrate used; i.e. tumour versus non tumour specimens. Nevertheless, a combination of multiple autoantibodies tested with the most appropriate substrate might be more sensitive and specific for the diagnosis of cholangiocarcinoma.
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Affiliation(s)
- Mohammad Zahid Mustafa
- Inserm, Unité 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Univ Paris-Sud, UMR-S 1193, Université Paris-Saclay, 94800, Villejuif, France.
- CASVAB, University of Balochistan, Quetta, Pakistan.
- DHU Hepatinov, 94800, Villejuif, France.
| | - Viet Hung Nguyen
- Inserm, Unité 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Univ Paris-Sud, UMR-S 1193, Université Paris-Saclay, 94800, Villejuif, France.
| | - François Le Naour
- Inserm, Unité 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Univ Paris-Sud, UMR-S 1193, Université Paris-Saclay, 94800, Villejuif, France.
- DHU Hepatinov, 94800, Villejuif, France.
| | - Eleonora De Martin
- Inserm, Unité 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Univ Paris-Sud, UMR-S 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Centre Hépato-Biliaire, AP-HP Hôpital Paul-Brousse, 94800, Villejuif, France.
- DHU Hepatinov, 94800, Villejuif, France.
| | - Elvire Beleoken
- Inserm, Unité 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Univ Paris-Sud, UMR-S 1193, Université Paris-Saclay, 94800, Villejuif, France.
- DHU Hepatinov, 94800, Villejuif, France.
| | - Catherine Guettier
- Inserm, Unité 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Univ Paris-Sud, UMR-S 1193, Université Paris-Saclay, 94800, Villejuif, France.
- DHU Hepatinov, 94800, Villejuif, France.
- Laboratoire Anatomie Pathologique, AP-HP Hôpital Bicêtre, 94270, Le Kremlin-Bicêtre, France.
| | - Catherine Johanet
- Inserm, Unité 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Univ Paris-Sud, UMR-S 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Département d'Immunologie Biologique, Unité d'autoimmunité, AP-HP Hôpital Saint Antoine, 75012, Paris, France.
- UFR 967 Faculté de Médecine, Université Pierre et Marie Curie, 75006, Paris, France.
| | - Didier Samuel
- Inserm, Unité 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Univ Paris-Sud, UMR-S 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Centre Hépato-Biliaire, AP-HP Hôpital Paul-Brousse, 94800, Villejuif, France.
- DHU Hepatinov, 94800, Villejuif, France.
| | - Jean-Charles Duclos-Vallee
- Inserm, Unité 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Univ Paris-Sud, UMR-S 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Centre Hépato-Biliaire, AP-HP Hôpital Paul-Brousse, 94800, Villejuif, France.
- DHU Hepatinov, 94800, Villejuif, France.
| | - Eric Ballot
- Inserm, Unité 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Univ Paris-Sud, UMR-S 1193, Université Paris-Saclay, 94800, Villejuif, France.
- Département d'Immunologie Biologique, Unité d'autoimmunité, AP-HP Hôpital Saint Antoine, 75012, Paris, France.
- DHU Hepatinov, 94800, Villejuif, France.
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Tagane S, Nguyen VH, Ngoc NV, Son HT, Toyama H, Yang CJ, Yahara T. Homalium glandulosum (Salicaceae), a new species from Vu Quang National Park, North Central Vietnam. PhytoKeys 2016; 58:97-104. [PMID: 26884709 PMCID: PMC4743018 DOI: 10.3897/phytokeys.58.6816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Accepted: 12/02/2015] [Indexed: 06/02/2023]
Abstract
Homalium glandulosum Tagane & V. H. Nguyen, from Vu Quang National Park in northern Vietnam, is newly described. This species is characterized by distinct glands, often stalked, at the base of the lamina and along the margin of the stipules and bracteoles. Illustrations, DNA barcodes of the two regions of rbcL and matK, and a key to the species of Homalium in Vietnam are also provided.
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Affiliation(s)
- Shuichiro Tagane
- Center for Asian Conservation Ecology, Kyushu University, 744 Motooka, Fukuoka, 819-0395, Japan
| | | | - Nguyen Van Ngoc
- Center for Asian Conservation Ecology, Kyushu University, 744 Motooka, Fukuoka, 819-0395, Japan
- Department of Biology, Dalat University, 01 – Phu Dong Thien Vuong, Dalat, Vietnam
| | - Hoang Thanh Son
- Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Ha Noi, 10999, Vietnam
| | - Hironori Toyama
- Center for Asian Conservation Ecology, Kyushu University, 744 Motooka, Fukuoka, 819-0395, Japan
| | - Chen-Jui Yang
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, Taiwan
| | - Tetsukazu Yahara
- Center for Asian Conservation Ecology, Kyushu University, 744 Motooka, Fukuoka, 819-0395, Japan
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Abstract
Vietnam is undergoing a rapid social and economic developments resulting in speedy urbanization, changes in methods for animal production, food marketing systems, and food consumption habits. These changes will have major impacts on human exposures to food poisoning. The present case study aimed to estimate hospitalization costs of foodborne diarrhea cases in selected health facilities in Vietnam. This is a facility-based cost-of-illness study conducted in seven health facilities in Northern Vietnam. All suspect cases of foodborne diarrhea, as diagnosed by doctors, who admitted to the studied health facilities during June-August, 2013 were selected. Costs associated with hospitalization for foodborne diseases were estimated from societal perspective using retrospective approach. We included direct and indirect costs of hospitalization of foodborne diarrhea cases. During the study period, 87 foodborne diarrhea cases were included. On average, the costs per treatment episode and per hospitalization day for foodborne diarrhea case were US$ 106.9 and US$ 33.6 respectively. Indirect cost (costs of times to patient, their relatives due to the patient's illness) made up the largest share (51.3%). Direct medical costs accounted for 33.8%; direct non-medical costs (patient and their relatives) represented 14.9%. Cost levels and compositions varied by level of health facilities. More attentions should be paid on prevention, control of foodborne diarrhea cases in Vietnam. Ensuring safety of food depends on efforts of everyone involved in food chain continuum, from production, processing, and transport to consumption.
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Affiliation(s)
- Van Minh Hoang
- Hanoi School of Public Health & Hanoi Medical University, Hanoi, Vietnam
| | - Tuan Anh Tran
- Center for health System Research, Hanoi Medical University, Hanoi, Vietnam
| | - Anh Duc Ha
- Cabinet Office, Ministry of Health, Hanoi, Vietnam
| | - Viet Hung Nguyen
- Hanoi School of Public Health & International Livestock Research Institute Vietnam, Hanoi, Vietnam
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Abstract
The thermoelectric properties of graphene and graphene nanostructures have recently attracted significant attention from the physics and engineering communities. In fundamental physics, the analysis of Seebeck and Nernst effects is very useful in elucidating some details of the electronic band structure of graphene that cannot be probed by conductance measurements alone, due in particular to the ambipolar nature of this gapless material. For applications in thermoelectric energy conversion, graphene has two major disadvantages. It is gapless, which leads to a small Seebeck coefficient due to the opposite contributions of electrons and holes, and it is an excellent thermal conductor. The thermoelectric figure of merit ZT of a two-dimensional (2D) graphene sheet is thus very limited. However, many works have demonstrated recently that appropriate nanostructuring and bandgap engineering of graphene can concomitantly strongly reduce the lattice thermal conductance and enhance the Seebeck coefficient without dramatically degrading the electronic conductance. Hence, in various graphene nanostructures, ZT has been predicted to be high enough to make them attractive for energy conversion. In this article, we review the main results obtained experimentally and theoretically on the thermoelectric properties of graphene and its nanostructures, emphasizing the physical effects that govern these properties. Beyond pure graphene structures, we discuss also the thermoelectric properties of some hybrid graphene structures, as graphane, layered carbon allotropes such as graphynes and graphdiynes, and graphene/hexagonal boron nitride heterostructures which offer new opportunities. Finally, we briefly review the recent activities on other atomically thin 2D semiconductors with finite bandgap, i.e. dichalcogenides and phosphorene, which have attracted great attention for various kinds of applications, including thermoelectrics.
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Affiliation(s)
- Philippe Dollfus
- Institut d'Electronique Fondamentale (IEF), Université Paris-Sud, CNRS, UMR 8622, Orsay, France
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Nguyen VH, Sibounheuang B, Phommasone K, Vongsouvath M, Newton PN, Piorkowski G, Baronti C, de Lamballerie X, Dubot-Pérès A. First isolation and genomic characterization of enterovirus A71 and coxsackievirus A16 from hand foot and mouth disease patients in the Lao PDR. New Microbes New Infect 2014; 2:170-2. [PMID: 25566395 PMCID: PMC4265048 DOI: 10.1002/nmi2.63] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [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: 06/27/2014] [Revised: 08/07/2014] [Accepted: 08/11/2014] [Indexed: 11/27/2022] Open
Abstract
Enterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16) are major aetiological agents of hand,
foot and mouth disease in Asia. We established the first genomic characterization of strains
isolated in 2011 from Lao patients. Isolates were related to EV-A71 genotype C4 and CV-A16 genotype
B1a that circulated in neighbouring countries during the same period. This confirms the regional
character of hand, foot and mouth disease epidemiology and makes plausible the occurrence of severe
disease in the Lao population.
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Affiliation(s)
- V H Nguyen
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health ; IHU Méditerranée Infection, APHM Public Hospitals of Marseille Marseille, France
| | - B Sibounheuang
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital Vientiane, Lao PDR
| | - K Phommasone
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital Vientiane, Lao PDR
| | - M Vongsouvath
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital Vientiane, Lao PDR
| | - P N Newton
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital Vientiane, Lao PDR ; Centre for Tropical Medicine, Nuffield Department of Medicine, Churchill Hospital, University of Oxford Oxford, United Kingdom
| | - G Piorkowski
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health ; IHU Méditerranée Infection, APHM Public Hospitals of Marseille Marseille, France
| | - C Baronti
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health
| | - X de Lamballerie
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health ; IHU Méditerranée Infection, APHM Public Hospitals of Marseille Marseille, France
| | - A Dubot-Pérès
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health ; Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital Vientiane, Lao PDR ; Centre for Tropical Medicine, Nuffield Department of Medicine, Churchill Hospital, University of Oxford Oxford, United Kingdom
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25
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Salmon S, Truong AT, Nguyen VH, Pittet D, McLaws ML. Health care workers' hand contamination levels and antibacterial efficacy of different hand hygiene methods used in a Vietnamese hospital. Am J Infect Control 2014; 42:178-81. [PMID: 24360520 DOI: 10.1016/j.ajic.2013.07.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [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: 03/04/2013] [Revised: 07/17/2013] [Accepted: 07/17/2013] [Indexed: 11/29/2022]
Abstract
BACKGROUND Handwashing with soap or another antisepsis disinfectant solution is a common practice in Vietnam, but the availability and quality of tap water is unpredictable. We assessed the risk for hand contamination and compared the efficacy of 5 hand hygiene methods in a tertiary Vietnamese hospital. METHODS Five fingertip imprints of the dominant hand of 134 health care workers (HCWs) were sampled to establish the average bacterial count before and after hand hygiene action using (1) alcohol-based handrub (ABHR), (2) plain soap and water handwashing with filtered and unfiltered water, or (3) 4% chlorhexidine gluconate hand antisepsis with filtered and unfiltered water. RESULTS Average bacterial contamination of hands before hand hygiene was 1.65 log(10). Acinetobacter baumannii, Klebsiella pneumoniae, and Staphylococcus aureus were the most commonly isolated bacterial pathogens. The highest average count before hand hygiene was recovered from HCWs without direct patient contact (2.10 ± 0.11 log(10)). Bacterial counts were markedly reduced after hand hygiene with ABHR (1.4 log(10); P < .0001) and 4% chlorhexidine gluconate with filtered water (0.8 log(10); P < .0001). Use of unfiltered water was associated with minimal nonsignificant bacterial reduction. CONCLUSIONS HCWs carry high levels of bacteria on their dominant hand, even without direct patient contact. ABHR as an additional step may overcome the effect of high bacterial counts in unfiltered water when soap and water handwashing is indicated.
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Affiliation(s)
- Sharon Salmon
- UNSW Medicine, University of New South Wales, Sydney, Australia
| | - Anh Thu Truong
- Department of Infection Control, Bach Mai Hospital, Hanoi, Vietnam
| | - Viet Hung Nguyen
- Department of Infection Control, Bach Mai Hospital, Hanoi, Vietnam
| | - Didier Pittet
- Infection Control Program and World Health Organization Collaborating Centre on Patient Safety, University of Geneva Hospitals and Faculty of Medicine, Geneva, Switzerland
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Abstract
A total of 56 people were affected with gastroenteritis after attending a one-day meeting in a high-quality hotel in the centre of Oslo, Norway, at the end of January 2011. A complete outbreak investigation was carried out. The microbiological investigation confirmed that the outbreak was caused by norovirus. All participants at the meeting were invited by email to complete an online questionnaire asking for information on demographic data, symptoms and food consumption. The results of the epidemiological investigation of the food items served were inconclusive and the source and transmission route of this outbreak remains unclear. However, the environmental investigation highlighted several irregularities in the kitchen that may have enabled the spread of the virus. Specific cleaning procedures and rules were set up for the kitchen staff. As a consequence of this outbreak investigation, the hotel is planning to change its internal routine protocols, for example, samples of food items served at every meal during an event will be stored.
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Affiliation(s)
- B Guzman-Herrador
- European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
- Norwegian Institute of Public Health, Oslo, Norway
| | - B T Heier
- Norwegian Institute of Public Health, Oslo, Norway
| | - E J Osborg
- Norwegian Food Safety Authority, Oslo, Norway
| | - V H Nguyen
- Norwegian Food Safety Authority, Oslo, Norway
| | - L Vold
- Norwegian Institute of Public Health, Oslo, Norway
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Salmon S, Nguyen VH, McLaws ML, Pittet D, Kilpatrick C, Le TAT, Truong AT. Hand hygiene campaigns in a low resource context: a Vietnam perspective. BMC Proc 2011. [PMCID: PMC3239433 DOI: 10.1186/1753-6561-5-s6-o22] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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28
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Nguyen TB, Nguyen VH, Fong W. SU-GG-T-159: Beam Angle Optimization for IMRT Plans. Med Phys 2010. [DOI: 10.1118/1.3468549] [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: 11/07/2022] Open
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29
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Getsios D, Caro J, Caro I, El-Hadi W, O’Brien JA, Chevat C, Coudeville L, Nguyen VH. 393: Health Economic Burden of Invasive Meningococcal Disease in the Us. J MöLler,. Am J Epidemiol 2005. [DOI: 10.1093/aje/161.supplement_1.s99] [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] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- D Getsios
- Caro Research Institute, Eslov, SWEDEN
| | - J Caro
- Caro Research Institute, Eslov, SWEDEN
| | - I Caro
- Caro Research Institute, Eslov, SWEDEN
| | - W El-Hadi
- Caro Research Institute, Eslov, SWEDEN
| | | | - C Chevat
- Caro Research Institute, Eslov, SWEDEN
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Abstract
Congenital Mid-line Cervical Cleft (CMCC) is a rare but interesting congenital anomaly of the neck that is frequently misdiagnosed. Much controversy exist regarding its aetiology. Embryologically, the occurrence of CMCC is thought to be due to many hypotheses that include impaired mid-line fusion of the first or second branchial arches, exteriorisation of a thyroglossal duct remnant, and or increased pressure in the cervical area from the pericardial roof in the developing embryo. Histologically, the cleft usually consists of a stratified keratinized squamous epithelium with hyperkeratosis, dermal fibrosis and little or no skin appendages. Associated clinical features could include thyroglossal duct cysts, cleft lip/mandible/sternum, cervical contractures, mandibular spurs, microgenia and or bronchogenic cysts. In this article we present a patient with CMCC. An extensive review of the literature is also included.
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Affiliation(s)
- A Mlynarek
- Department of Otolaryngology, McGill University, Montreal, Canada
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31
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Abstract
BACKGROUND/PURPOSE The aim of this study was to review the presentations of gastrointestinal duplication (GID) and to assess the influence of prenatal diagnosis on treatment. METHODS Retrospective review of all GID at 2 pediatric hospitals from 1980-2002 was conducted. RESULTS Seventy-three patients (M43:F30) were identified: 21 neonates, 28 infants (1 to 24 months), 15 children (1 to 10 years), 9 adolescents (>/=11 years). GID location by frequency was ileum (31.5%), ileocaecal valve (30.2%), duodenum (9.6%), stomach (8.2%), jejunum (8.2%), colon (6.8%), and rectum (5.5%). In neonates and infants, vomiting and distension were the most common presentations. Volvulus, caused by a duplication, occurred in 23.8% of neonates and caused the death of one neonate. Intussusception was identified in 10.9% of patients. In older children and adolescents, pain and vomiting were the most common associations. Six of these patients were being treated for Crohn's disease, with the diagnosis of duplication made at laparotomy. Eighteen patients had a prenatal diagnosis by ultrasound scan, with 77.2% of these asymptomatic after birth. Most prenatal diagnoses occurred after 1991 (77.8%). When comparing an earlier period (1980 to 1991; 29 patients) with the current (1992 to 2002; 44 patients), a greater proportion of the latter patients were asymptomatic (36.4 v 13.8%) and had a lower incidence of complications (volvulus/intussusception). CONCLUSIONS GID can lead to life-threatening complications. Prenatal diagnosis should lead to expeditious postnatal investigation and treatment before the onset of symptoms or complications. GID in older children can mimic Crohn's disease. Laparoscopy/laparotomy should be considered in patients with atypical Crohn's disease or when the diagnosis of an intraabdominal mass is unclear.
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Affiliation(s)
- P S Puligandla
- Divisions of Division of Pediatric Surgery and Pathology, The Montreal Children's Hospital, Montreal, Quebec, Canada
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Abstract
Patch-clamp recordings were carried out in the inside-out configuration in human keratinocytes of the cell line HaCaT. Patch pipettes were filled with 150 mM KCl, 1 mM CaCl(2) and 10 mM HEPES. In symmetrical KCl solutions, single channel currents from a large conductance channel (about 170 pS) were measured. Replacement of 120 mM KCl by K-aspartate had only a minor influence on the single channel conductance and on the reversal potential. In intracellular solution in which K(+) has been replaced by Na(+) or NMDG(+), the reversal potential shifted to > + 40 mV indicating K(+) as the main charge carrier. The channels were neither dependent on intracellular Ca(2+) (between 0.8 nM and 10 micro M), ATP (at 0 and 1 mM) nor Mg(2+) (at 0 and 0.5 mM). The mean current showed an outward rectification that can be mainly attributed to the voltage dependence of the open probability. The channels displayed bursting kinetics with a mean open time of about 2 ms and closed times of about 0.2, 2 and 20 ms. The mean open probability was usually low (0.05) but increased occasionally (0.6) mainly due to a lower probability of long closings. We conclude that these K(+) channels contribute to the resting potential of human keratinocytes which may control the Ca(2+) influx and thereby their proliferation and differentiation.
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Affiliation(s)
- V H Nguyen
- Julius-Bernstein-Institut for Physiology, Martin-Luther-University Halle-Wittenberg, Halle/Saale, Germany
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Abstract
OBJECTIVES our study aimed to evaluate the cost-effectiveness of influenza vaccination in high-risk children in Argentina. METHODS a decision analysis model was performed, using data from published and unpublished sources, to compare two strategies--to vaccinate or not to vaccinate. We simulated the expected consequences of vaccination on direct medical costs, related to disease management and indirect costs, related to lost parental working days (absenteeism). RESULTS Using base-case assumptions vaccination of high-risk children aged 6 months to 15 years old, in Argentina (estimated cohort of 1184748) would prevent 207331 cases of influenza, resulting in a reduction of 58052 days of hospitalization and 207331 outpatient visits. Vaccination would lead to net savings of US$ 11894870 per vaccinated cohort (US$ 10.04 per vaccinated child). CONCLUSION our economic analysis shows that in Argentina, routine vaccination of high-risk children against influenza would be cost saving for society.
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Affiliation(s)
- G H Dayan
- Fundación Centro de Estudios Infectológicos, Buenos Aires, Argentina.
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Zhang HJ, Tamez PA, Vu DH, Ghee TT, Nguyen VH, Le TX, Le MH, Nguyen MC, Do TT, Soejarto DD, Fong HH, Pezzuto JM. Antimalarial compounds from Rhaphidophora decursiva. J Nat Prod 2001; 64:772-777. [PMID: 11421741 DOI: 10.1021/np010037c] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Bioassay-directed fractionation led to the isolation of 14 compounds, six of which possess antimalarial activity, from the dried leaves and stems of Rhaphidophora decursiva. Polysyphorin (1) and rhaphidecurperoxin (6) showed strong activities against Plasmodium falciparum. Rhaphidecursinol A (2), rhaphidecursinol B (3), grandisin (4), and epigrandisin (5) were less active against the same organism. Among the isolates, rhaphidecursinol A (2) and rhaphidecursinol B (3) were determined to be new neolignans, and rhaphidecurperoxin (6) is a new benzoperoxide. Known compounds isolated include polysyphorin (1), grandisin (4), epigrandisin (5), (+)-medioresinol, (-)-pinoresinol, (-)-syringaresinol, (+)-glaberide I, (+)-dehydrovomifoliol, (-)-liliolide, (-)-hydroxydihydrobovolide, and N-butylbenzamide, of which compound 1 appears worthy of further evaluation as an antimalarial agent. Structure elucidation and identification were accomplished by spectroscopic means including 1D and 2D NMR analyses.
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Affiliation(s)
- H J Zhang
- Program for Collaborative Research in Pharmaceutical Sciences, m/c 877, College of Pharmacy, the University of Illinois at Chicago, 833 S. Wood Street, Chicago, Illinois 60612, USA
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35
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Qiu SX, Nguyen VH, Le TX, Gu JQ, Lobkovsky E, Tran CK, Soejarto DD, Clardy J, Pezzuto JM, Dong Y, Mai VT, Le MH, Fong HH. A pregnane steroid from Aglaia lawii and structure confirmation of cabraleadiol monoacetate by X-ray crystallography. Phytochemistry 2001; 56:775-780. [PMID: 11314967 DOI: 10.1016/s0031-9422(00)00463-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [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
The pregnane steroid, (E)-aglawone, along with four known triterpenes, and a known sterol mixture were isolated from the bark of Aglaia lawii (Wight) Saldanha ex Ramamoorty (Meliaceae). The structural determination/identification was accomplished by a combination of 1D- and 2D-NMR spectroscopic techniques. The relative stereochemistry of the known triterpene, 20S,24S-epoxydammarane-3alpha,25-diol acetate, was also unequivocally determined for the first time by X-ray crystallography. The isolates were not active against various human cancer cell lines.
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Affiliation(s)
- S X Qiu
- Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, 60612, USA
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Wood SC, Nguyen VH, Schmidt C. Economic evaluations of influenza vaccination in healthy working-age adults. Employer and society perspective. Pharmacoeconomics 2000; 18:173-183. [PMID: 11067651 DOI: 10.2165/00019053-200018020-00007] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [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
OBJECTIVE To determine what benefits to the employer and to society are associated with influenza (flu) vaccination in healthy adults. DESIGN AND METHODS We performed a literature review concerning cost-benefit and cost-effectiveness evaluations of influenza vaccination in healthy, working-age adults. Up to the end of 1999, we found 6 published economic evaluations on the use of influenza vaccine in healthy, working-age adults: 3 prospective studies, 1 retrospective evaluation and 2 model-based simulations. Evaluations were performed from the perspective of an employer or society. Costs were reported in the local currency used in the published evaluation, with conversions into US dollars (when not provided in the article), for comparative purposes only, according to the exchange rates of June 8 1998. MAIN OUTCOME MEASURES AND RESULTS Estimations of the cost-benefit of vaccination, compared with a no vaccination strategy, varied widely from a net loss of $US106.59 per infection averted in one study to savings of varying sizes in the 5 others (savings ranged from $US2.58 per dollar invested to $US46.85 per vaccinee). Studies differed in the definition of illness and the measurement of costs associated with vaccination or illness. CONCLUSIONS Decision makers have not yet extended existing vaccine recommendations to cover healthy, working-age adults, partly because of the disparity among economic studies in their methods of estimating costs and measuring effects. However, the published studies seem to suggest that influenza vaccination in the healthy, working adult would be a cost-effective health intervention, at least from the perspective of an employer.
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Affiliation(s)
- S C Wood
- Aventis Pasteur International, Lyon, France.
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37
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Nguyen VH, Trout J, Connors SA, Andermann P, Weinberg E, Mullins MC. Dorsal and intermediate neuronal cell types of the spinal cord are established by a BMP signaling pathway. Development 2000; 127:1209-20. [PMID: 10683174 DOI: 10.1242/dev.127.6.1209] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.3] [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: 11/20/2022]
Abstract
We have studied the role of Bmp signaling in patterning neural tissue through the use of mutants in the zebrafish that disrupt three different components of a Bmp signaling pathway: swirl/bmp2b, snailhouse/bmp7 and somitabun/smad5. We demonstrate that Bmp signaling is essential for the establishment of the prospective neural crest and dorsal sensory Rohon-Beard neurons of the spinal cord. Moreover, Bmp signaling is necessary to limit the number of intermediate-positioned lim1+ interneurons of the spinal cord, as observed by the dramatic expansion of these prospective interneurons in many mutant embryos. Our analysis also suggests a positive role for Bmp signaling in the specification of these interneurons, which is independent of Bmp2b/Swirl activity. We found that a presumptive ventral signal, Hh signaling, acts to restrict the amount of dorsal sensory neurons and trunk neural crest. This restriction appears to occur very early in neural tissue development, likely prior to notochord or floor plate formation. A similar early role for Bmp signaling is suggested in the specification of dorsal neural cell types, since the bmp2b/swirl and bmp7/snailhouse genes are only coexpressed during gastrulation and within the tail bud, and are not found in the dorsal neural tube or overlying epidermal ectoderm. Thus, a gastrula Bmp2b/Swirl and Bmp7/Snailhouse-dependent activity gradient may not only act in the specification of the embryonic dorsoventral axis, but may also function in establishing dorsal and intermediate neuronal cell types of the spinal cord.
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Affiliation(s)
- V H Nguyen
- University of Pennsylvania School of Medicine, Department of Cell and Developmental Biology, 421 Curie Blvd, Philadelphia, PA 19104-6058, USA
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38
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Affiliation(s)
- S C Wood
- Pasteur Mérieux Connaught International, 58, Ave Leclerc, BP 7046, 69348, Lyon, France.
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Affiliation(s)
- A Tasset
- Health Economics Unit, Pasteur Mérieux Connaught International, 58, ave Leclerc, BP 7046, 69348, Lyon, France.
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40
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Namer IJ, Bolo NR, Sellal F, Nguyen VH, Nedelec JF, Hirsch E, Marescaux C. Combined measurements of hippocampal N-acetyl-aspartate and T2 relaxation time in the evaluation of mesial temporal lobe epilepsy: correlation with clinical severity and memory performances. Epilepsia 1999; 40:1424-32. [PMID: 10528939 DOI: 10.1111/j.1528-1157.1999.tb02015.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [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: 12/20/2022]
Abstract
PURPOSE In this study we tried to find a correlation between the clinical severity and memory performances, by comparing proton magnetic resonance (MR) spectroscopy and T2 relaxation time measurements in the hippocampi, in a homogeneous group of 27 patients with unilateral mesial temporal lobe epilepsy with ipsilateral hippocampal sclerosis on MR imaging, with a view to answer the following questions: (a) how sensitive is this approach for the assessment of the apparently normal contralateral hippocampus, (b) do the results relate to the clinical severity, and (c) does it allow evaluation of the degree of hippocampal dysfunction. METHODS Volume-selective proton MR spectroscopy of the head of both hippocampi was performed at 3 T, by using the PRESS sequence, with an echo time of 135 ms, to estimate NAA/(Cho + Cr) ratios. The relaxation times were measured at 0.28 T, by using a conventional Carr-Purcell-Meiboom-Gill sequence, with a repetition time of 2,000 ms, an echo time of 15 ms, and 48 echoes. RESULTS The combination of NAA/(Cho + Cr) ratio and T2 relaxation time values was allowed to classify contralateral hippocampus abnormalities in two groups: first, decreased NAA/(Cho + Cr) ratio with strongly increased T2 relaxation time values corresponding to abnormalities observed in sclerotic ipsilateral hippocampi; and second, decreased NAA/(Cho + Cr) ratio with normal or slightly increased T2 relaxation time values. Whereas the NAA/(Cho + Cr) ratio or T2 relaxation time value alone was not correlated with memory performances, their association shows that left hippocampal injury evaluated both by NAA and T2 relaxation time measurements was clearly correlated with verbal memory scores, and right hippocampal injury, with visual memory scores. On the other hand, the maximal seizure frequency reported by the patients was correlated with ipsilateral NAA/(Cho + Cr) ratio and T2 relaxation time values but not with contralateral results. CONCLUSIONS We showed that the combination of NAA and T2 relaxation time measurements can be used to examine the degree of ipsi- and contralateral hippocampal dysfunction or injuries and their relations with memory performances in the presurgical evaluation of patients.
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Affiliation(s)
- I J Namer
- Université Louis Pasteur, Institut de Physique Biologique (UPRES-A 7004 CNRS), Faculté de Médecine, Strasbourg, France.
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41
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Abstract
N-(4-phenylbutyl)-3-hydroxy-4-azahexacyclo[5.4.1.0(2,6).0(3, 10).0(5,9) .0(8,11)]dodecane (ANSTO-14) showed the highest activity for the sigma 1 site (Ki = 9.4 nM) and 19-fold sigma 1/sigma 2 selectivity. The present study showed that [3H]ANSTO-14 binds to a single high-affinity site in guinea pig brain membranes with an equilibrium Ki of 8.0 +/- 0.3 nM, in good agreement with the kinetic studies (Kd = 13.3 +/- 5.4 nM, n = 4), and a Bmax of 3.199 +/- 105 fmol/mg protein (n = 4). The in vivo biodistribution of [3H]ANSTO-14 showed a high uptake in the diencephalon. Pretreatment of rats with sigma ligands including (+)-pentazocine (sigma 1), ANSTO-14 (sigma 1), and DTG (sigma 1 and sigma 2) did not significantly reduce radiotracer uptake in the brain, but did in the spleen. A labelled metabolite was found in the liver and brain. Due to its insensitivity to sigma ligands, the accumulation of [3H]ANSTO-14 in the brain indicates high nonspecific binding. Therefore, [3H]ANSTO-14 is a suitable ligand for labelling sigma 1 sites in vitro but is not suitable for brain imaging of sigma binding sites in vivo.
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Affiliation(s)
- V H Nguyen
- Department of Pharmacology, The University of Sydney, NSW, Australia.
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Nguyen VH, Leroux MA, Badeaux J, Zabjek K, Coillard C, Rivard CH. [Classification of left thoracolumbar scoliosis according to its radiologic morphology and its postural geometry]. Ann Chir 1998; 52:752-60. [PMID: 9846425] [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: 02/09/2023]
Abstract
Idiopathic scoliosis is a tridimensional (3D) deformation of the spine associated with postural geometry (PG) disorganisation. Conventional classification of scoliosis is primarily based on the analysis of PA X-rays. This is a descriptive classification that forms heterogeneous groups. Diagnosis, prognosis and treatments are then developed around partial information. The goal of this project was to divide the left thoracolumbar (TLG) class in two subgroups using exhaustive analysis of the PA and lateral X-rays, and the evaluation of postural deformations. The quantification of the PG of 14 control subjects and 20 scoliotic patients (TLG) was realised using a stereovideographic approach. For each patient, PA and lateral X-rays were done using a digital X-ray apparatus. The TLG group shows common pathological characteristics but is forming a relatively heterogeneous group. When this class is divided in two subgroups, 9 postural parameters appeared to be different from the control group, each subgroup showing specific postural characteristics. The 3D quantification of pertinent radiological parameters and the PG evaluation should allow the classification of idiopathic scoliosis patients. Furthermore, these groups of patients could be characterised, in order to improve the diagnosis, the prognosis and the treatment, with a brace or surgically.
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Affiliation(s)
- V H Nguyen
- Service de Chirurgie, Faculté de Médecine, Université de Montréal, Hôpital Sainte-Justine, Québec, Canada
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43
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Abstract
Biological actions of novel sigma1- and sigma2-selective binding site ligands (trishomocubanes: 4-azahexacyclo [5.4.1.0.(2,6).0(3,10).0(5,).0(8,11)]dodecanes), and the reference ligands, 1,3-di(2-tolyl)-guanidine (DTG), haloperidol, (+)-pentazocine and dextromethorphan, were studied in rat locus coeruleus neurons using intracellular and whole-cell patch clamp recordings. High concentrations of trishomocubanes produced small inward currents and affected some parameters of action potential waveforms suggesting modest potency to inhibit ionic conductances underlying action potentials. Sigma-ligands produced large inward currents in the presence of mu-opioid, alpha2-adrenoceptor and ORL1 receptor agonists. These reversed polarity near the K+ equilibrium potential, suggesting that sigma-ligands act as ligand activated K+-channel blockers or interfere with the coupling between these receptors and K+-channels. However, no correlation was found between binding affinities at sigma1- or sigma2-binding sites and potency to inhibit K+-currents, suggesting that these effects on K+-channels are not directly related to occupancy of sigma binding sites.
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Affiliation(s)
- V H Nguyen
- Department of Pharmacology, The University of Sydney, NSW, Australia
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44
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Abstract
We report a case a carbamazepine (CBZ) intoxication with negative myoclonus that occurred 4 weeks after clobazam (CLB) had been added to a stable regimen of CBZ and topiramate (TPM). Both CBZ and CBZ-epoxide (CBZ-E) blood levels were elevated, and the symptoms resolved quickly when CBZ dosage was reduced and CLB discontinued. CLB was reintroduced a year later with the patient's consent, and the time course of the interaction was studied: CBZ and CBZ-E levels increased slowly over 12 days. The interaction is thus probably related to the progressive increase in Nor-CLB.
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Affiliation(s)
- P Genton
- Centre Saint Paul, Marseille, France
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Svensson US, Ashton M, Trinh NH, Bertilsson L, Dinh XH, Nguyen VH, Nguyen TN, Nguyen DS, Lykkesfeldt J, Le DC. Artemisinin induces omeprazole metabolism in human beings. Clin Pharmacol Ther 1998; 64:160-7. [PMID: 9728896 DOI: 10.1016/s0009-9236(98)90149-7] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.7] [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: 11/24/2022]
Abstract
OBJECTIVE This study investigated whether time-dependent artemisinin pharmacokinetics correlated to CYP3A4 or CYP2C19 activity in vivo. METHODS Artemisinin (two oral doses per day of 250 mg) was given to nine healthy Vietnamese subjects for 7 days (day 1 to day 7). Single 20 mg doses of omeprazole were given orally on day -7, day 1, and day 7. Single doses of artemisinin and omeprazole were given in combination on day 14 after a 6-day washout period. The pharmacokinetics of artemisinin, omeprazole, hydroxyomeprazole, and omeprazole sulfone were evaluated on days -7, 1, 7, and 14. On the same days urine was collected for the determination of 6beta-hydroxycortisol and cortisol excretion. RESULTS Areas under plasma concentration-time curves (AUC) for artemisinin and omeprazole decreased on day 7 to 20% (95% confidence intervals, 13%, 28%) and 35% (25%, 46%), respectively, compared with values on day 1. AUC ratios for hydroxyomeprazole/omeprazole increased 2.2-fold (1.7, 2.7) on day 7 compared with values on day 1. All values were normalized at day 14. There were no significant changes in the omeprazole sulfone/omeprazole ratio or in the 6beta-hydroxycortisol/cortisol ratio between the study days. In one subject found to have poor CYP2C19 metabolization, the elimination of omeprazole increased after artemisinin exposure, with no change in the hydroxyomeprazole/omeprazole AUC ratio. CONCLUSION Artemisinin did not alter CYP3A4 activity, whereas an increase in CYP2C19 activity was observed. The increased elimination of omeprazole in both poor and extensive CYP2C19 metabolizers suggests artemisinin induces both CYP2C19 and another enzyme.
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Affiliation(s)
- U S Svensson
- Department of Pharmacy, Uppsala University, Sweden
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Nguyen VH, Schmid B, Trout J, Connors SA, Ekker M, Mullins MC. Ventral and lateral regions of the zebrafish gastrula, including the neural crest progenitors, are established by a bmp2b/swirl pathway of genes. Dev Biol 1998; 199:93-110. [PMID: 9676195 DOI: 10.1006/dbio.1998.8927] [Citation(s) in RCA: 366] [Impact Index Per Article: 14.1] [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: 11/22/2022]
Abstract
A bone morphogenetic protein (BMP) signaling pathway is implicated in dorsoventral patterning in Xenopus. Here we show that three genes in the zebrafish, swirl, snailhouse, and somitabun, function as critical components within a BMP pathway to pattern ventral regions of the embryo. The dorsalized mutant phenotypes of these genes can be rescued by overexpression of bmp4, bmp2b, an activated BMP type I receptor, and the downstream functioning Smad1 gene. Consistent with a function as a BMP ligand, swirl functions cell nonautonomously to specify ventral cell fates. Chromosomal mapping of swirl and cDNA sequence analysis demonstrate that swirl is a mutation in the zebrafish bmp2b gene. Interestingly, our analysis suggests that the previously described nonneural/neural ectodermal interaction specifying the neural crest occurs through a patterning function of swirl/bmp2b during gastrulation. We observe a loss in neural crest progenitors in swirl/bmp2b mutant embryos, while somitabun mutants display an opposite, dramatic expansion of the prospective neural crest. Examination of dorsally and ventrally restricted markers during gastrulation reveals a successive reduction and reciprocal expansion in nonneural and neural ectoderm, respectively, in snailhouse, somitabun, and swirl mutant embryos, with swirl/bmp2b mutants exhibiting almost no nonneural ectoderm. Based on the alterations in tissue-specific gene expression, we propose a model whereby swirl/bmp2b acts as a morphogen to specify different cell types along the dorsoventral axis.
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Affiliation(s)
- V H Nguyen
- Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, USA
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Ashton M, Gordi T, Trinh NH, Nguyen VH, Nguyen DS, Nguyen TN, Dinh XH, Johansson M, Le DC. Artemisinin pharmacokinetics in healthy adults after 250, 500 and 1000 mg single oral doses. Biopharm Drug Dispos 1998; 19:245-50. [PMID: 9604124 DOI: 10.1002/(sici)1099-081x(199805)19:4<245::aid-bdd99>3.0.co;2-z] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [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: 11/09/2022]
Abstract
Eight healthy male, Vietnamese subjects were administered 1 x 250, 2 x 250, and 4 x 250 mg artemisinin capsules in a cross-over design with randomized sequence with a 7-day washout period between administrations. The inter-individual variability in artemisinin pharmacokinetics was large with parameter coefficient of variation (CV) typically between 50-70%. The parameter with the smallest variability was the elimination half-life (CV approximately equal to 30-40%). Analysis of variance indicated also a large intra-subject variability. (CV, or = 24%) for the dose-normalized area under the plasma concentration-time curve (AUC/dose). The pharmacokinetic results suggested artemisinin to be subject to high pre-systemic extraction. Artemisinin half-life could not predict the extent of in vivo exposure to the drug, there being no correlation between half-life and oral clearance. Artemisinin oral plasma clearance was about 400 L h-1 exhibiting a slight decrease with dose, although the effect was weak. Thus results from studies using different artemisinin doses may, within the studied dose range, be compared without the complication of disproportionate changes in drug exposure with varying dose levels. Half-lives appeared to increase with dose. An observed period effect in the analysis of variance was tentatively associated with time-dependency in artemisinin pharmacokinetics. There was a high correlation between artemisinin plasma concentrations determined at various time-points after drug administration and the AUCs after the 500 and 1000 mg doses, but less so after the 250 mg dose. This may show a tentative approach to assess the systemic exposure of the patients to artemisinin from the determination of artemisinin plasma concentrations in one or two plasma samples only. Artemisinin was well tolerated with no apparent dose or time dependent effects on blood pressure, heart rate or body temperature.
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Affiliation(s)
- M Ashton
- Department of Pharmacy, Uppsala University, Sweden.
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Ashton M, Nguyen DS, Nguyen VH, Gordi T, Trinh NH, Dinh XH, Nguyen TN, Le DC. Artemisinin kinetics and dynamics during oral and rectal treatment of uncomplicated malaria. Clin Pharmacol Ther 1998; 63:482-93. [PMID: 9585803 DOI: 10.1016/s0009-9236(98)90044-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.4] [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: 02/07/2023]
Abstract
OBJECTIVE To compare parasite clearance times after oral and rectal administration of artemisinin in adults with uncomplicated malaria and to relate pharmacodynamics with artemisinin kinetics and to disclose any pharmacokinetic changes during treatment. METHODS Thirty male Vietnamese patients with falciparum malaria were randomized to treatment with 500 mg artemisinin daily by either the oral or rectal route of administration. Parasite densities in capillary blood were determined by microscopy every 4 to 6 hours. Artemisinin plasma concentrations on the first and last day of treatment were determined by HPLC and unbound fractions in plasma were determined by ultrafiltration. RESULTS Mean parasite clearance times and 95% confidence intervals (95% CI) were 25 (95% CI, 16 to 33) and 29 (95% CI, 23 to 35) hours during oral and rectal treatment, respectively. The bioavailability after rectal relative to oral artemisinin was 30%. Artemisinin areas under the plasma concentration-time curve (AUC) on the fifth (last) day of oral or rectal treatment were 30% (95% CI, 4% to 56%) and 40% (95% CI, -6% to 91%), respectively, of those after the first dose. The fraction unbound in plasma was 15% (95% CI, 12% to 19%), increasing marginally during treatment. No relationship was found between main clinical end points and drug exposure, although indices for the rapidity of response onset were lower after oral treatment and correlated to unbound AUC values (rS = -0.7; p < 0.001). CONCLUSIONS The similarity in parasite clearance times despite lower drug levels during rectal treatment suggests that initial oral doses may be unnecessarily high. The singular time dependency of artemisinin pharmacokinetics, attributed to autoinduction of drug elimination, has possible implications for combination chemotherapy. Decreasing artemisinin concentrations during treatment may partly explain recrudescences and increase the risk for resistance development.
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Affiliation(s)
- M Ashton
- Department of Pharmacy, Uppsala University, Sweden
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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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Nguyen VH, Kassiou M, Johnston GA, Christie MJ. Comparison of binding parameters of sigma 1 and sigma 2 binding sites in rat and guinea pig brain membranes: novel subtype-selective trishomocubanes. Eur J Pharmacol 1996; 311:233-40. [PMID: 8891604 DOI: 10.1016/0014-2999(96)00395-0] [Citation(s) in RCA: 39] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Comparisons of binding parameters of [3H](+)-pentazocine and [3H]1,3-di-o-tolylguanidine (DTG) at sigma binding sites in guinea pig and rat brain membranes demonstrated that [3H](+)-pentazocine binds to a single high-affinity site, whereas [3H]DTG binds to two high-affinity sites in both species. The Kd values of the radioligands were similar in both types of membranes. However, the density of sigma 1 sites in guinea pig was significantly higher than that of rat. Novel trishomocubanes were tested for their affinities at sigma 1 and sigma 2 binding sites in guinea pig brain membranes using [3H](+)-pentazocine and [3H]DTG as the radioligands. N-(4-Phenylbutyl)-3-hydroxy-4- azahexacyclo[5.4.1.0(2,6).0(3,10).0(5,9).0(8,11)]dodecane (ANSTO-14) showed the highest affinity for the sigma 1 site (Ki = 9.4 nM) and 19-fold sigma 1/sigma 2 selectivity, as a result of increasing the alkyl chain between the cubane moiety and the aromatic ring. N-(3'-Fluorophenyl)methyl- 3-hydroxy-4-azahexacyclo[5.4.1.0(2,6).0(3,10).0(5,9).0(8,11]dodeca ne (ANSTO-19), displayed the highest affinity for sigma 2 sites (Ki = 19.6 nM) and 8-fold sigma 2/sigma 1 selectivity due to a fluoro substitution in the meta position of the aromatic ring. These represent structurally novel lead compounds, especially for the development of selective sigma 2 receptor ligands.
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Affiliation(s)
- V H Nguyen
- Department of Pharmacology, University of Sydney, NSW, Australia
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