28 results on '"Van-Dan Nguyen"'
Search Results
2. Heart Rate Variability during Auricular Acupressure at Heart Point in Healthy Volunteers: A Pilot Study
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Dieu-Thuong Thi Trinh, Que-Chi Thi Nguyen, Minh-Man Pham Bui, Van-Dan Nguyen, and Khac-Minh Thai
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Article Subject ,Complementary and alternative medicine ,otorhinolaryngologic diseases - Abstract
Heart rate variability (HRV) is the variation in time between each heartbeat. Increasing HRV may contribute to improving autonomic nervous system dysfunctions. Acupuncture stimulation through the vagus plexus in the ear is considered as a method that can improve HRV. In this pilot study, we examined 114 healthy volunteers at the Faculty of Traditional Medicine, University of Medicine and Pharmacy at Ho Chi Minh City, from January to May 2020. During a 20-minute interval, participants were stimulated two times at the acupoint in the left ear with Semen seed. The heart rate and HRV values were monitored before, during, and after acupressure every 5 minutes. When we compared the experimental group with the control group, HRV significantly increased in the stage of ear-stimulated acupressure compared with the stage before and after the auricular acupressure ( p = 0.01 , p = 0.04 , p = 0.04 and p = 0.02 ) and the difference was not statistically significant compared with the phase of nonstimulated ( p = 0.15 , p = 0.28 ). The changes in other values including SDNN (standard deviation of the average NN), RMSSD (root mean square of successive RR interval differences), LF (low-frequency power), and HF (high-frequency power) in all stages were not statistically significant p = > 0.05 between groups. Based on the results, we can determine the increase in HRV when conducting auricular acupressure with stimulation at the heart acupoint on the left ear. This leads to a direction in further studies for clinical application for patients with autonomic nervous disorder.
- Published
- 2022
3. Successful Radiofrequency Ablation of the Right Lateral Accessory Pathway with Modified Carpentier Reconstruction Surgery in a Patient with Ebstein Anomaly Concomitant of Secundum Atrial Septal Defect, Atrial Fibrillation, and Wolff–Parkinson–White Syndrome
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Van Dan Nguyen, Xuan Tuan Nguyen, Van Tung Pham, and Le Tra Pham
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cardiovascular system ,General Engineering ,cardiovascular diseases - Abstract
Ebstein anomaly (EA) results from the failure of proper delamination of the tricuspid valve leaflets from the right ventricle (RV) myocardium. The severity of EA occurs on a spectrum that results in varying degrees of tricuspid regurgitation, atrial dilation, RV dilation, and dysfunction. These effects have the potential to create substrates that can give rise to atrial arrhythmia, ventricular arrhythmia, and a greater incidence of Wolff–Parkinson–White (WPW) syndrome Wackel et al. (2018) accounting for 0.5% of all congenital heart diseases (Oh et al. 1985). In the case of atrial fibrillation and WPW, it is very dangerous for the patient because of hemodynamic compromise, syncope, and sudden death. In this case report, we share our experience in using radiofrequency ablation to ablate right lateral accessory pathway, with modified Carpentier technique in operation to treat an adult patient diagnosed with Ebstein anomaly, atrial septal defect, atrial fibrillation, and WPW syndrome.
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- 2022
4. Isolation, structural elucidation and molecular docking studies against SARS-CoV-2 main protease of new stigmastane-type steroidal glucosides isolated from the whole plants of Vernonia gratiosa
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Van Cong, Pham, Le Tuan Anh, Hoang, Trung, Nguyen Quang, Minh, Bui Quang, Duc, Ngo Viet, Van Dan, Nguyen, Trang, Nguyen Minh, Phong, Nguyen Viet, Vinh, Le Ba, Anh, Le Tuan, and Lee, Ki Yong
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Organic Chemistry ,Plant Science ,Biochemistry ,Analytical Chemistry - Abstract
Phytochemical investigation of the whole plants of Vernonia gratiosa Hance. led in the isolation and identification of two new stigmastane-type steroidal glucosides (1–2), namely vernogratiosides A (1), and B (2). Their chemical structures were fully elucidated based on 1 D/2D NMR spectroscopic, HR-ESI-MS data analyses, and by producing derivatives by chemical reactions. The binding potential of the isolated compounds to replicase protein − main protease of SARS-CoV-2 were examined using the molecular docking simulations. Our results show that the isolated steroidal glucosides (1–2) bind to the substrate‐binding site of SARS-CoV-2 main protease with binding affinities of −7.2 and −7.6 kcal/mol, respectively, as well as binding abilities equivalent to N3 inhibitor that has already been reported (–7.5 kcal/mol).
- Published
- 2022
5. A Smartphone-Controllable Molecular Diagnostic Platform for Sars-Cov-2 Detection by Reverse-Transcription Recombinase Polymerase Amplification
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Van Dan Nguyen, Huynh Quoc Nguyen, Hoang Khang Bui, and Tae Seok Seo
- Published
- 2023
6. ẢNH HƯỞNG CỦA TÍNH CHẤT ĐỒ THỊ LÊN RÀNG BUỘC GIỮA CÁC BẤT BIẾN TRONG CÂY VÀ ĐỒ THỊ PHẲNG
- Author
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Thi Khanh Trinh Vu, Van Dan Nguyen, and Chi Nguyen Khong
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Combinatorics ,Vertex (graph theory) ,symbols.namesake ,Close relationship ,symbols ,Graph theory ,Tree (graph theory) ,Graph ,Mathematics ,Planar graph - Abstract
Lý thuyết đồ thị là một ngành Toán học có nhiều ứng dụng quan trọng trong Tin học và trong thực tế. Những ý tưởng cơ bản được đề ra bởi nhà toán học Thuỵ sĩ Leonhar Euler (1707-1783). Ông đã dùng đồ thị để giải quyết bài toán nổi tiếng về 7 chiếc cầu ở Konigsberg. Bằng mô hình đồ thị, chúng ta có thể giải quyết được nhiều bài toán thực tế như: tìm cách để tham quan một triển lãm sao cho mỗi một hành lang đi qua đúng một lần, tìm số mầu ít nhất để tô mầu bản đồ, biểu diễn sự ảnh hưởng lẫn nhau giữa các cá nhân trong một tổ chức hay sự cạnh tranh giữa các loài trong môi trường tự nhiên... Giữa tính chất của đồ thị và các bất biến trong đồ thị có mối liên hệ ràng buộc chặt chẽ với nhau. Bài báo này chỉ trình bày một số kết quả về ảnh hưởng của tính chất của đồ thị lên ràng buộc giữa các bất biến trong cây và đồ thị phẳng.
- Published
- 2021
7. An Integrated Smartphone-Based Genetic Analyzer for Qualitative and Quantitative Pathogen Detection
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Tae Seok Seo, Hau Van Nguyen, Van Dan Nguyen, and Fei Liu
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Detection limit ,Spectrum analyzer ,Materials science ,business.industry ,General Chemical Engineering ,Loop-mediated isothermal amplification ,General Chemistry ,Chip ,Article ,law.invention ,Lens (optics) ,Chemistry ,CMOS ,law ,Multiplex ,business ,QD1-999 ,Computer hardware ,Light-emitting diode - Abstract
The use of the smartphone is an ideal platform to realize the future point-of-care (POC) diagnostic system. Herein, we propose an integrated smartphone-based genetic analyzer. It consists of a smartphone and an integrated genetic analysis unit (i-Gene), in which the power of the smartphone was utilized for heating the gene amplification reaction, and the camera function was used for imaging the colorimetric change of the reaction for quantitative and multiplex foodborne pathogens. The housing of i-Gene was fabricated by using a 3D printer, which was equipped with a macro lens, white LEDs, a disposable microfluidic chip for loop-mediated isothermal amplification (LAMP), a thin-film heater, and a power booster. The i-Gene was installed on the iPhone in alignment with a camera. The LAMP mixture for Eriochrome Black T (EBT) colorimetric detection was injected into the LAMP chip to identify Escherichia coli O157:H7, Salmonella typhimurium, and Vibrio parahaemolyticus. The proportional–integral–derivative controller-embedded film heater was powered by a 5.0 V power bank to maintain 63 °C for the LAMP reaction. When the LAMP proceeded, the color was changed from violet to blue, which was real-time monitored by the smartphone complementary metal oxide semiconductor camera. The images were transported to the desktop computer via Wi-Fi. The quantitative LAMP profiles were obtained by plotting the ratio of green/red intensity versus the reaction time. We could identify E. coli O157:H7 with a limit of detection of 101 copies/μL within 60 min. Our proposed smartphone-based genetic analyzer offers a portable, simple, rapid, and cost-effective POC platform for future diagnostic markets.
- Published
- 2020
8. Auricular Acupressure Effect on Autonomic Responses Evoked by a Cold Pressor Test in Healthy Volunteers: A Pilot Study
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Dieu-Thuong Thi Trinh, Van-Huy Nguyen, Minh-Man Pham Bui, Van-Dan Nguyen, Thu-Thao Thi Nguyen, Hoai-Nam Thai, and Khac-Minh Thai
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Complementary and alternative medicine ,Article Subject - Abstract
Objective. This pilot study was conducted to investigate changes in the pulse rate and blood pressure in healthy volunteers after applying auricular acupressure at the “heart acupoint.” Methods. A total of 120 healthy volunteers with hemodynamic indexes within normal limits were randomly allocated into 4 groups to receive auricular acupressure treatment either at the heart acupoint of the left or the right, or in both ears, and one control group without applying auricular acupressure. Results. Before the application of auricular acupressure, there were no statistical differences in pulse rate and blood pressure increments among the four groups during the first cold pressor test. In groups in which auricular pressure was applied, the pulse rate was significantly reduced after the application of auricular acupressure in three groups; however, no statistically significant difference was detected among the groups. Changes in blood pressure were not statistically significant in or among the different groups after applying auricular acupressure. The average recorded pulse rate values during the second cold pressor test (after auricular acupressure) were significantly lower compared to the corresponding values taken during the first cold pressor test (before auricular acupressure) ( p p > 0.05). Conclusions. These findings suggest that auricular acupressure could be used as an adjunctive nonpharmacological method for reducing the pulse rate.
- Published
- 2022
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9. Prediction of acute rejection in kidney transplanted patients based on the point-of-care isothermal molecular diagnostics platform
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Van Dan Nguyen, Hau Van Nguyen, Jung Woo Seo, Sang Ho Lee, and Tae Seok Seo
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Graft Rejection ,Point-of-Care Systems ,Electrochemistry ,Biomedical Engineering ,Biophysics ,Humans ,General Medicine ,Biosensing Techniques ,Pathology, Molecular ,Kidney ,Nucleic Acid Amplification Techniques ,Biotechnology - Abstract
In this study, we proposed an advanced point-of-care molecular diagnostic technology to evaluate the acute rejection (AR) in kidney transplanted patients. On the contrary to the conventional PCR method, we developed a colorimetric loop mediated isothermal amplification (LAMP) for quantitative analysis of the six biomarkers related to AR (CD3ϵ, IP-10, Tim-3-HAVCR2, CXCL9, PSMB9, C1QB) with a reference gene (18S rRNA). Using urinary cDNA samples of transplanted patients, it turned out that three biomarkers among six, namely IP-10, Tim-3-HAVCR2 and C1QB, have significant discrepancy in quantity between the stable graft (STA) patient and the AR patient. The AR prediction model using these three biomarkers was established, which could estimate the immune-rejection in the patients with 93.3% of accuracy. For the point-of-care (POC) molecular diagnostics for the AR evaluation, we constructed a centrifugal microfluidic platform, in which the RNA extraction from the clinical urinary samples, the quantitative reverse-transcription (RT)-LAMP reaction, and the data analysis based on the AR prediction model could be performed in a serial order. Ten blind clinical samples were analyzed on the POC genetic analyzer, showing 100% match with the validated qPCR data. Thus, the proposed advanced molecular diagnostic platform enables us to perform the timely treatment for the transplanted patients who are suffering from the allograft failure and side effects such as infection and malignancy.
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- 2021
10. Effect of auricular acupuncture on exam anxiety in first-year medical students
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Thao Nguyen Thi Thu, Dieu-Thuong Thi Trinh, Duc-Thang Pham, Minh-Man Pham Bui, Loc Le Quang, Van-Dan Nguyen, and Hoai-Nam Thai
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medicine.medical_specialty ,Dry needling ,Relaxation (psychology) ,business.industry ,Visual analogue scale ,medicine.drug_class ,education ,Tranquilizer ,Heart rate ,Physical therapy ,Medicine ,Anxiety ,Observational study ,medicine.symptom ,business ,State-Trait Anxiety Inventory - Abstract
Background and Objectives: Exam anxiety is a commonly seen problem among medical students. Auricular acupuncture has been shown to have an anxiety-reducing effect, however, data on exam anxiety is limited. Research in dental and preoperative anxiety has indicated that anxiety level could be reduced by using ear acupoints on the non-dominant side. Therefore, this study aims to determine whether needling at acupoints on the non-dominant side can reduce exam anxiety in medical students. Method: This is a prospective observational study on 32 students at The Faculty of Traditional Medicine, Ho Chi Minh City University of Medicine and Pharmacy. Eligible students received auricular acupuncture on the non-dominant side at the Master cerebral, Tranquilizer and Relaxation points. Levels of anxiety were measured using a visual analogue scale before and after the intervention as well as before the exam. The State-Trait Anxiety Inventory, heart rate, exam performance and adverse events occurring during the study were also collected. Results: Exam anxiety level and heart rate decreased 30 minutes after auricular acupuncture (p0.05). No adverse events from auricular acupuncture were observed. Conclusion: Auricular acupuncture at the Master cerebral, Tranquillizer and Relaxation points on the non-dominant side is effective in reducing exam anxiety in medical students.
- Published
- 2019
11. The efficiency of combining modified acupuncture and motor relearning method on post-stroke patients
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Hoai-Nam Thai, Minh-Man Pham Bui, Van-Dan Nguyen, and Dieu-Thuong Thi Trinh
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Modern medicine ,medicine.medical_specialty ,Rehabilitation ,business.industry ,medicine.medical_treatment ,General Medicine ,medicine.disease ,law.invention ,Randomized controlled trial ,law ,Paralysis ,medicine ,Post stroke ,Physical therapy ,Acupuncture ,medicine.symptom ,Motor Deficit ,business ,Stroke - Abstract
Background and Objectives: Combining modern medicine and traditional medicine in the rehabilitation of post-stroke motor deficit has shown interesting results. Many studies on modified acupuncture, a combination of modern and traditional techniques, have proven its effectiveness in motor rehabilitation in post-stroke patients. Furthermore, the effectiveness of the motor relearning method in the treatment of post-stroke paralysis has been elucidated. Therefore, our study aims to determine whether the combination between modified acupuncture and motor relearning method can improve treatment outcomes. Method: Multicenter randomized controlled trial (Traditional Medicine Hospital of Ho Chi Minh City, General Hospital of Soc Trang Province, and People Military Hospital of Soc Trang Province) from July 2014 to July 2015. 66 post-stroke patients were divided into two groups: The control group received modified acupuncture combined with Bobath method and the trial group received modified acupuncture combined with motor relearning method. After six weeks, patients were evaluated according to the Barthel score, the 10-hole test, and the ability to walk. Results: The trial group showed better results than the control group. There was a significant difference between the two groups in the Barthel score and the ability to walk, excluding the 10-hole test. After treatment, 77.42% of patients in the trial group showed improvement compared to only 51.61% in the control group (P < 0.05). Conclusion: The combination of modified acupuncture and motor relearning method is more effective than the combination of modified acupuncture and Bobath method in the rehabilitation of motor deficit after stroke.
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- 2019
12. A Review of Traditional Uses, Phytochemistry and Pharmacological Properties of Some Vietnamese Wound-Healing Medicinal Plants
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Oanh Hoang Hua, Quynh Thi Thuy Tran, Dieu-Thuong Thi Trinh, Van-Dan Nguyen, Duc Phan Nguyen Duong, and Triet Thanh Nguyen
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Pharmacology ,integumentary system ,Complementary and alternative medicine ,fungi ,Drug Discovery ,food and beverages ,Plant Science ,General Medicine - Abstract
Wound healing is a sophisticated process that results in the repair of damaged tissues. Any impairment to this process can lead to non-healing (chronic) wounds. Since these can cause a massive burden on the healthcare system, alternative therapies that promote wound healing should be considered. Therapies of natural origins that are safe and with no adverse side effects are especially promising. Vietnam, a tropical-climate country, has many medicinal plants that possess the potential for healing wounds. This report explores the use of some common plants used in Traditional Vietnamese medicine and their molecular mechanisms.
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- 2022
13. A handheld-type total integrated capillary electrophoresis system for SARS-CoV-2 diagnostics: Power, fluorescence detection, and data analysis by smartphone
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Khang Hoang Bui, Tae Seok Seo, Bum Jun Park, Huynh Quoc Nguyen, Van Dan Nguyen, and Young Soo Ko
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Data Analysis ,SARS-CoV-2 ,Computer science ,business.industry ,Biomedical Engineering ,Biophysics ,COVID-19 ,Electrophoresis, Capillary ,Biosensing Techniques ,General Medicine ,Converters ,Molecular diagnostics ,Signal ,Fluorescence spectroscopy ,Electropherogram ,Capillary electrophoresis ,CMOS ,Electrochemistry ,Humans ,Smartphone ,business ,Computer hardware ,Biotechnology ,Point of care - Abstract
A micro-capillary electrophoresis (μCE) system is one of the widely adopted techniques in the molecular diagnostics and DNA sequencing due to the benefits of high resolution, rapid analysis, and low reagent consumption, but due to the requirements of bulky high-power suppliers and an expensive laser-induced fluorescence detector module, the conventional set-up of μCE system is not adequate for point-of-care (POC) molecular diagnostics. In this study, we constructed a miniaturized and integrated μCE system which can be manipulated by a smartphone. The smartphone not only powers two boost converters and an excited laser, but also controls the relay for the power switch. Moreover, the complementary metal-oxide-semiconductor (CMOS) camera of the smartphone was used for detecting the fluorescence signal of amplicons amplified with reverse transcription-polymerase chain reaction (RT-PCR). We also developed a web-based application so that the raw data of the recorded fluorescence intensity versus the running time can display typical capillary electropherograms on the smartphone. The total size of the hand-held μCE system was 9.6 cm [Width] × 22 cm [Length] × 15.5 cm [Height], and the weight was ∼1 kg, which is suitable for POC DNA testing. In the integrated smartphone-associated μCE system, we could accurately analyze two genes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), namely N gene and S gene along with two bracket ladders in 6 min to identify SARS-CoV-2. Such an advanced μCE platform can be applied for a variety of on-site molecular diagnostics fields with user-friendliness.
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- 2022
14. Nucleic acid diagnostics on the total integrated lab-on-a-disc for point-of-care testing
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Tae Seok Seo, Tin Hoang Trung Chau, Eun Yeol Lee, Hau Van Nguyen, Huynh Quoc Nguyen, and Van Dan Nguyen
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Computer science ,Point-of-care testing ,Microfluidics ,Biomedical Engineering ,Biophysics ,Context (language use) ,Centrifugation ,02 engineering and technology ,01 natural sciences ,Polymerase Chain Reaction ,Lab-On-A-Chip Devices ,Nucleic Acids ,Electrochemistry ,Animals ,Humans ,Process engineering ,business.industry ,010401 analytical chemistry ,General Medicine ,Equipment Design ,021001 nanoscience & nanotechnology ,Molecular diagnostics ,Centrifugal microfluidics ,0104 chemical sciences ,Point-of-Care Testing ,Lab on a disc ,0210 nano-technology ,business ,Biotechnology - Abstract
Since the emergence of the lab-on-a-chip technology in 1979, a variety of microfluidic devices have been developed and utilized for chemical and biological applications. Among the microfluidic devices, the centrifugal microfluidic device or lab-on-a-disc (LOAD) has advanced remarkably due to simple operation by the rotation, total integration, and high-throughput capability. Moreover, the centrifugal microdevices do not need complex tubing and pumping systems, which render them ideal for point-of-care testing (POCT) system. Owing to these characteristics, the centrifugal microdevices have been extensively used for bio-diagnostics. In particular, molecular diagnostics, which are regarded as an essential method for definite determination of the targets related with diseases, have been widely applied on the LOAD. In this review paper, we focus on the molecular diagnostics on the LOAD. The steps for the molecular diagnostics such as cell lysis, genome purification, gene amplification, amplicon detection, and data analysis can be performed individually or totally on the LOAD. Future directions of the LOAD in the fields of bio-diagnostics is to realize POCT for U-healthcare monitoring. In this context, the latest LOAD strategies for molecular diagnostics are summarized in this review paper, which would provide an insight for future POCT platform.
- Published
- 2019
15. Point-of-care genetic analysis for multiplex pathogenic bacteria on a fully integrated centrifugal microdevice with a large-volume sample
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Hau Van Nguyen, Tae Seok Seo, Eun Yeol Lee, and Van Dan Nguyen
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Salmonella typhimurium ,Spectrum analyzer ,Materials science ,Point-of-Care Systems ,Microfluidics ,Biomedical Engineering ,Biophysics ,Loop-mediated isothermal amplification ,Food Contamination ,02 engineering and technology ,Escherichia coli O157 ,01 natural sciences ,Foodborne Diseases ,Cartridge ,Limit of Detection ,Microsystem ,Lab-On-A-Chip Devices ,Electrochemistry ,Multiplex ,Detection limit ,Chromatography ,010401 analytical chemistry ,General Medicine ,021001 nanoscience & nanotechnology ,DNA extraction ,0104 chemical sciences ,Vibrio parahaemolyticus ,0210 nano-technology ,Nucleic Acid Amplification Techniques ,Biotechnology - Abstract
We present a fully integrated portable centrifugal microsystem for multiplex detection of food poisoning bacteria with a large volume of sample up to 1 mL. The microsystem consists of a portable genetic analyzer and a fully integrated centrifugal microdevice. The centrifugal microdevice is designed with two units: a 3D printed solution-loading cartridge and a centrifugal microfluidic disc. All the essential solutions for loop-mediated isothermal amplification (LAMP) reaction are stored inside the cartridge, and orderly released into centrifugal microdevice by a rotation program. Each unit of the device is designed with 20 reaction chambers for simultaneous detection of food-borne bacteria in one test. To increase the amount of a sample to 1 mL, we incorporated the super absorbent polymer (SAP) in the waste chamber to absorb the sample and the washing solution during the device operation. The whole process was automatically conducted including designated solution release, bead-based DNA extraction, isothermal gene amplification by Eriochrome Black (EBT)-mediated LAMP reaction, and colorimetric and UV–visible detection of amplicons. The ratio between Abs640nm and Abs570nm was used as a criterion to confirm the positive result, and the result was positive upon the condition of Abs640/Abs570 ≥ 1.0. To demonstrate the pathogenic bacteria detection on our proposed microsystem, we targeted three kinds of bacteria (Escherichia coli O157:H7, Salmonella typhimurium, and Vibrio parahaemolyticus) for monoplex and multiplex detection. The whole process from sample to result was completed within 1 h with a low limit of detection (LOD) of 102 cells/mL.
- Published
- 2019
16. Neuroblastoma in Vietnam: A retrospective analysis of MYCN status and clinical features to inform prognosis and improve outcome
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Van Dan Nguyen, Uyen Dp Nguyen, Niem Vt Vo, Dinh Q Truong, Diem-My Vu, Khai D Truong, Diem Kd Truong, Ban T Ho, Uyen Ht Nguyen, and Chi-Bao Bui
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Oncology ,medicine.medical_specialty ,business.industry ,Neuroblastoma ,Internal medicine ,medicine ,Retrospective analysis ,business ,medicine.disease ,Outcome (game theory) - Published
- 2019
17. Identification for a Large-volume Food-borne Bacteria on a Fully Integrated Portable Centrifugal Disc
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Eun Yeol Lee, Tae Seok Seo, Hau Van Nguyen, and Van Dan Nguyen
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Spectrum analyzer ,Cartridge ,Materials science ,Chromatography ,Volume (thermodynamics) ,Elution ,Microsystem ,Microfluidics ,Loop-mediated isothermal amplification ,Multiplex - Abstract
Herein, we present a fully integrated portable centrifugal microsystem for multiplex detection of food poisoning bacteria with a large volume of sample up to 1 mL. The microsystem consists of a portable rotary genetic analyzer and a fully integrated lab-on-a-disc device. The portable rotary genetic analyzer is equipped with a couple of heating blocks, a motor and a UV-Vis optical detector. The device was designed with two units: a 3D printed solution-loading cartridge and a centrifugal microfluidic disc. All the essential solutions for the LAMP reaction (a sample, a washing, an elution and a LAMP cocktail solution) are stored inside the cartridge, and orderly released into centrifugal microdevice by a rotation program. Each unit of the device was designed with 20 reaction chambers for simultaneously detecting 19 kinds of food poisoning bacteria in one test. To increase the amount of a sample to 1 mL, we incorporated the super absorbent polymer (SAP) in the waste chamber to absorb the sample and washing solution during the device operation. The whole process was automatically conducted from bead-based DNA extraction to isothermal DNA amplification by LAMP reaction to colorimetric and UV-vis detection of amplicons in 60 min to identify three kinds of bacteria (Escherichia coli O157:H7, Salmonella Typhimurium, and Vibrio parahaemolyticus).
- Published
- 2019
18. Smart phone-powered capillary electrophoresis on a chip for foodborne bacteria detection
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Khang Hoang Bui, Tae Seok Seo, Hau Van Nguyen, and Van Dan Nguyen
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Materials science ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,law.invention ,Electric power system ,Capillary electrophoresis ,law ,Materials Chemistry ,Electrical and Electronic Engineering ,Instrumentation ,business.industry ,Metals and Alloys ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Chip ,Cathode ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Anode ,Electropherogram ,Boost converter ,Optoelectronics ,0210 nano-technology ,business ,Voltage - Abstract
Due to the requirement of high-voltage power supply, on-chip micro-capillary electrophoresis (μCE) suffers from practical on-site bioapplications. In this paper, we introduced a smart phone based electric power system for μCE on a chip with simple electrical operations and improved portability of a μCE device. Since the power of the smart phone is limited to 5 V, we utilized a boost converter circuit to increase up to 250 V, which enables μCE on a chip. The typical μCE channel with a cross design was patterned on the PMMA substrate, and the sample, the waste, the anode and the cathode reservoirs were fabricated. Two steps of μCE consisting of the injection and the separation were performed to separate two amplicons (121 bp FliC gene of Escherichia coli and 161 bp InvA gene of Salmonella serovar Typhimurium). During the injection step, the voltages applied in the sample and waste reservoirs were 0 V and 250 V, respectively, and the amplicons were filled in the injection channel (6.8 mm length) in 50 s. We switched the power supply to the anode reservoir with 250 V and the cathode reservoir with 0 V. Two amplicons were successfully separated in the separation channel (17 mm length) in 4 min. In order to assign the peak in the electropherogram, we added two bracket ladders with the amplicon sample, so that we could accurately identify the target peak based on a relative migration time.
- Published
- 2019
19. Central and Peripheral Cultures and the Problem of Social Conflict
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Van Dan Nguyen
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Social conflict ,Sociology ,Social psychology ,Peripheral - Published
- 2018
20. Quantitative trait loci mapping of partial resistance to Diamondback moth in cabbage (Brassica oleracea L)
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Jonghyun Na, Shahnaz Begum, Van Dan Nguyen, Moo-Kyoung Yoon, Nirala Ramchiary, Su Ryun Choi, Xiaonan Li, Hye Y. Song, Hyeran Kim, Wenxing Pang, Yong Pyo Lim, Ajay Kumar, Mechuselie Kehie, and Min Kwon
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Genetic Markers ,Breeding program ,Genetic Linkage ,Quantitative Trait Loci ,Population ,Brassica ,Breeding ,Moths ,Quantitative trait locus ,Biology ,Gene mapping ,Botany ,Genetics ,Animals ,Herbivory ,Plant breeding ,education ,education.field_of_study ,Diamondback moth ,fungi ,Chromosome Mapping ,food and beverages ,General Medicine ,biology.organism_classification ,Phenotype ,Genetic marker ,Brassica oleracea ,Agronomy and Crop Science ,Biotechnology - Abstract
The resistance to Diamondback moth insect in cabbage is governed by many minor loci in quantitative nature, and at least four genetic loci should be incorporated in marker-assisted breeding program for developing partially resistant DBM cabbage cultivars. The Diamondback moth (DBM), Plutella xylostella (L.), is the most destructive insect infesting cruciferous plants worldwide. Earlier studies have reported that the glossy leaves of cabbage are associated with resistance to this insect. However, until now, genetics of DBM resistance has not been studied in detail, and no QTL/gene mapping for this trait has been reported. In this paper, we report quantitative trait loci (QTL) mapping of DBM-resistant trait using 188 randomly selected segregating F 3 population derived from crossing a partially DBM-resistant glossy leaf cabbage (748) with a susceptible smooth cabbage line (747). Quantitative trait loci mapping using phenotypic data of four consecutive years (2008, 2009, 2010, and 2011) on DBM insect infestation detected a total of eight QTL on five linkage groups suggesting that DBM resistance is a quantitative in nature. Of these QTL, four QTL, i.e., qDbm 1 on LG1, qDbm5 and qDbm6 on LG7, and qDbm8 on LG9, were detected in different tests and years. The QTL, qDbm6 on LG7, was consecutively detected over 3 years. Tightly linked molecular markers have been developed for qDbm8 QTL on LG9 which could be used in marker-assisted breeding program. Our research demonstrated that for desired DBM resistance cultivar breeding, those four genetic loci have to be taken into consideration. Furthermore, the comparative study revealed that DBM resistance QTL is conserved between close relative model plant Arabidopsis thaliana and Brassica oleracea genome.
- Published
- 2015
21. Anti-inflammatory and wound healing activities of calophyllolide isolated from Calophyllum inophyllum Linn
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Thanh Niem Van Vo, Hieu K. Huynh, Dieu Thuong Thi Trinh, Van Linh Nguyen, Cong Tri Truong, Chi-Bao Bui, Trong Thuc Dao, Binh Cao Quan Nguyen, and Van Dan Nguyen
- Subjects
0301 basic medicine ,Male ,Physiology ,medicine.medical_treatment ,Anti-Inflammatory Agents ,lcsh:Medicine ,Gene Expression ,Pharmacology ,Pathology and Laboratory Medicine ,Biochemistry ,Mice ,White Blood Cells ,0302 clinical medicine ,Fibrosis ,Coumarins ,Animal Cells ,Immune Physiology ,Medicine and Health Sciences ,lcsh:Science ,Immune Response ,Skin ,Innate Immune System ,Multidisciplinary ,integumentary system ,Sodium Dodecyl Sulfate ,Animal Models ,Cytokine ,Experimental Organism Systems ,030220 oncology & carcinogenesis ,Seeds ,Cytokines ,medicine.symptom ,Inflammation Mediators ,Cellular Types ,Research Article ,medicine.drug_class ,Cell Survival ,Immune Cells ,Immunology ,Inflammation ,Mouse Models ,Research and Analysis Methods ,Anti-inflammatory ,Proinflammatory cytokine ,03 medical and health sciences ,Signs and Symptoms ,Model Organisms ,Diagnostic Medicine ,Tissue Repair ,medicine ,Genetics ,Animals ,Humans ,Viability assay ,Peroxidase ,Wound Healing ,Blood Cells ,business.industry ,Macrophages ,lcsh:R ,Biology and Life Sciences ,Proteins ,Cell Biology ,Molecular Development ,medicine.disease ,HaCaT ,030104 developmental biology ,RAW 264.7 Cells ,Gene Expression Regulation ,Immune System ,lcsh:Q ,business ,Wound healing ,Calophyllum ,Physiological Processes ,Collagens ,Biomarkers ,Spleen ,Developmental Biology - Abstract
Due to the high-cost and limitations of current wound healing treatments, the search for alternative approaches or drugs, particularly from medicinal plants, is of key importance. In this study, we report anti-inflammatory and wound healing activities of the major calophyllolide (CP) compound isolated from Calophyllum inophyllum Linn. The results showed that CP had no effect on HaCaT cell viability over a range of concentrations. CP reduced fibrosis formation and effectively promoted wound closure in mouse model without causing body weight loss. The underlying molecular mechanisms of wound repair by CP was investigated. CP markedly reduced MPO activity, and increased M2 macrophage skewing, as shown by up-regulation of M2-related gene expression, which is beneficial to the wound healing process. CP treatment prevented a prolonged inflammatory process by down-regulation of the pro-inflammatory cytokines-IL-1β, IL-6, TNF-α, but up-regulation of the anti-inflammatory cytokine, IL-10. This study is the first to indicate a plausible role for CP in accelerating the process of wound healing through anti-inflammatory activity mechanisms, namely, by regulation of inflammatory cytokines, reduction in MPO, and switching of macrophages to an M2 phenotype. These findings may enable the utilization of CP as a potent therapeutic for cutaneous wound healing.
- Published
- 2016
22. A 3D printed screw-and-nut based droplet generator with facile and precise droplet size controllability
- Author
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Huynh Quoc Nguyen, Tae Seok Seo, Van Dan Nguyen, and Hau Van Nguyen
- Subjects
Nut ,Fabrication ,Materials science ,Metals and Alloys ,02 engineering and technology ,Thread (computing) ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Controllability ,chemistry.chemical_compound ,chemistry ,Linear motion ,Materials Chemistry ,Particle size ,Electrical and Electronic Engineering ,Composite material ,0210 nano-technology ,Instrumentation ,Lithography ,Ethylene glycol - Abstract
Herein, we present the fabrication of a novel vertical T-junction based droplet generator using a desktop 3D printer and the production of a variety of size of polymer particles by tuning the vertical T-junction gap height (hg) with ease. The droplet generator device consists of two main components: an internal thread nut with a vertical T-junction droplet generator unit, and a screw with an external thread for adjusting hg. The two components were fabricated by a 3D printer and assembled simply by a bolt-and-nut combination. The clockwise or counter-clockwise rotation of the screw is converted into the downward and upward linear motion of the screw, adjusting the hg value. The hg value can be tuned precisely from 0 to 750 μm by designing 75 control teeth on the top of the screw. The size of the produced droplets is proportional to the hg value. The size range of the droplets was 39–1404 μm, when hg changed from 20 to 200 μm. We synthesized poly(ethylene glycol) diacrylate (PEGDA) particles using the droplet as a reactor, and accordingly the PEGDA particle size could be controlled. Our proposed 3D printed droplet generator is rapid, simple and cost-effective to be fabricated without need of lithographic processes.
- Published
- 2019
23. Analysis of the Genetic Diversity of Radish Germplasm through SSR Markers Derived from Chinese Cabbage
- Author
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Suhyoung Park, Su Ryun Choi, Van Dan Nguyen, Sunggil Kim, Yong Pyo Lim, and Jung-Soo Lee
- Subjects
Crop ,Germplasm ,Genetic diversity ,Genetic resources ,business.industry ,Genotype ,food and beverages ,Genetic relationship ,General Medicine ,Sample collection ,Biology ,business ,Biotechnology - Abstract
Since the early 1980s, the National Institute of Horticultural & Herbal Sciences has been breeding and collecting diverse radish breeds to select those samples with better horticultural characteristics, to ultimately expand and develop as good radish produce. Genetic diversity is a crucial factor in crop improvement and therefore it is very important to obtain various variations through sample collection. The collected samples were compared with one another in order to assess the level of diversity among the collections, and this procedure allowed for increased application of the gathered resources and aided in determining the direction to secure further samples. Towards this end, this experiment was conducted in order to examine whether the SSR markers derived from Chinese cabbage samples could be transferred to the radish samples. Among the radish breeding lines and introduced resources, 44 lines were used as materials to analyze the genotype using 22 SSR markers selected. As a result, the analysis showed that among all the selected markers, 'cnu_m139' and 'cnu_m289' were the most useful markers for diversity evaluation. The genetic relationship of the radish genetic resources showed that the geographic origins affected the diversity. Furthermore, the different types of radish groups were also determined by the year they were bred. This result demonstrated that there are differences between the older radish breeds and the more recently developed radish breeds. Even though a relatively small number of markers were used in the analysis, it was possible to distinguish whether the radish was bred 30 years ago or in the 2000s, and that the similar physical shapes comprised a particular group, showed that the SSR markers can indeed be successfully applied to to study the diversity within radish breeding lines. Through the results of this study, it can be concluded that the SSR marker developed for the Chinese cabbage can be applied to examine the genetic diversity and analyze the relationship (genetic resource determination) of radish.
- Published
- 2013
24. Mapping QTLs of resistance to head splitting in cabbage (Brassica oleracea L.var. capitata L.)
- Author
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Yoon-Young Kim, Jacqueline Batley, Wenxing Pang, Vignesh Dhandapani, David Edwards, Hyeran Kim, Jin Gyu Kim, Su Ryun Choi, Nirala Ramchiary, Jonghyun Na, Xiaonan Li, Yong Pyo Lim, and Van Dan Nguyen
- Subjects
Genetics ,biology ,Bulked segregant analysis ,Chromosome ,Karyotype ,Plant Science ,Quantitative trait locus ,biology.organism_classification ,Homologous chromosome ,Brassica oleracea ,Arabidopsis thaliana ,Agronomy and Crop Science ,Molecular Biology ,Biotechnology ,Synteny - Abstract
Cabbage head splitting can greatly affect both the quality and commercial value of cabbage (Brassica oleracea). To detect the genetic basis of head-splitting resistance, a genetic map was constructed using an F2 population derived by crossing “748” (head-splitting-resistant inbred line) and “747” (head-splitting-susceptible inbred line). The map spans 830.9 cM and comprises 270 markers distributed in nine linkage groups, which correspond to the nine chromosomes of B. oleracea. The average distance between adjacent markers was 3.6 cM. A total of six quantitative trait loci (QTLs) conferring resistance to head splitting were detected in chromosome 2, 4, and 6. Two QTLs, SPL-2-1 and SPL-4-1, on chromosomes 2 and 4, respectively, were detected in the experiments over 2 years, suggesting that these two potential loci were important for governing the head-splitting resistance trait. Markers BRPGM0676 and BRMS137, which were tightly linked with head-splitting resistance, were detected in the conserved QTL SPL-2-1 region using bulked segregant analysis. Synteny analysis showed that SPL-2-1 was anchored to a 3.18-Mb genomic region of the B. oleracea genome, homologous to crucifer ancestral karyotype E block in chromosome 1 of Arabidopsis thaliana. Moreover, using a field emission scanning electron microscope, significant differences were observed between the two parental lines in terms of cell structures. Line “747” had thinner cell wall, lower cell density, larger cell size, and anomalous cell wall structure compared with the resistant line “748.” The different cell structures can provide a cytological base for assessing cabbage head splitting.
- Published
- 2015
25. Multi-constrained routing algorithm: a networking evaluation
- Author
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Van Dan Nguyen, Isabelle Guérin-Lassous, Thomas Begin, Dynamic Networks : Temporal and Structural Capture Approach (DANTE), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire de l'Informatique du Parallélisme (LIP), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut Rhône-Alpin des systèmes complexes (IXXI), École normale supérieure - Lyon (ENS Lyon)-Université Lumière - Lyon 2 (UL2)-Université Joseph Fourier - Grenoble 1 (UJF)-Université Jean Moulin - Lyon 3 (UJML), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Université Lumière - Lyon 2 (UL2)-Université Joseph Fourier - Grenoble 1 (UJF)-Université Jean Moulin - Lyon 3 (UJML), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and École normale supérieure de Lyon (ENS de Lyon)-Université Lumière - Lyon 2 (UL2)-Université Joseph Fourier - Grenoble 1 (UJF)-Université Jean Moulin - Lyon 3 (UJML)
- Subjects
Routing protocol ,Dynamic Source Routing ,Computer science ,Equal-cost multi-path routing ,Routing table ,Distributed computing ,Enhanced Interior Gateway Routing Protocol ,Wireless Routing Protocol ,050801 communication & media studies ,02 engineering and technology ,Routing Information Protocol ,[INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI] ,0508 media and communications ,0202 electrical engineering, electronic engineering, information engineering ,Destination-Sequenced Distance Vector routing ,Hierarchical routing ,Triangular routing ,Static routing ,Zone Routing Protocol ,Adaptive quality of service multi-hop routing ,business.industry ,Quality of service ,05 social sciences ,Policy-based routing ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,020206 networking & telecommunications ,Supernetwork ,Routing domain ,Link-state routing protocol ,Multipath routing ,Interior gateway protocol ,The Internet ,business ,Computer network - Abstract
International audience; IP networks may face issues to support the offered workload due to the increasing number of Internet users, the steady influx of new Internet applications, which require stringent QoS, and applications needing big data transmission. QoS routing can be viewed as an attractive approach to tackle this issue. However, most of the QoS routing solutions are not evaluated in a realistic framework. In this paper we propose a networking evaluation of multi-constrained routing to assess the potential benefit of QoS routing protocol. To do this, we converted a multi-constrained routing algorithm into a protocol, and implemented it in the simulator NS2. Our results indicate that if the monitoring tool of a network can not sustain frequent link-state announcements, the benefits coming from implementing a QoS routing are quite low. On the other hand, if the network is equipped with an adequate measurement tool, then QoS routing can be worth implementing, and the routing based only the available bandwidth at each link arises as the best option (no need to consider the end-to-end delay constraint, nor the loss rate constraint).
- Published
- 2013
26. Genic microsatellite markers in Brassica rapa: development, characterization, mapping, and their utility in other cultivated and wild Brassica relatives
- Author
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Yong Pyo Lim, Vignesh Dhandapani, Chang Pyo Hong, Van Dan Nguyen, Zhong Yun Piao, Su Ryun Choi, Ge Yu, Nirala Ramchiary, and Xiaonan Li
- Subjects
Genetic Markers ,Chromosomes, Artificial, Bacterial ,Positional cloning ,DNA, Plant ,Brassica ,Biology ,Quantitative trait locus ,Gene mapping ,Genetic linkage ,Brassica rapa ,Genetics ,Molecular Biology ,Alleles ,Expressed Sequence Tags ,Expressed sequence tag ,Polymorphism, Genetic ,transferability ,food and beverages ,Chromosome Mapping ,expressed sequence-derived SSRs ,General Medicine ,Full Papers ,Genetic marker ,Microsatellite ,polymorphism information content ,integrated map ,Genome, Plant ,Microsatellite Repeats - Abstract
Genic microsatellite markers, also known as functional markers, are preferred over anonymous markers as they reveal the variation in transcribed genes among individuals. In this study, we developed a total of 707 expressed sequence tag-derived simple sequence repeat markers (EST-SSRs) and used for development of a high-density integrated map using four individual mapping populations of B. rapa. This map contains a total of 1426 markers, consisting of 306 EST-SSRs, 153 intron polymorphic markers, 395 bacterial artificial chromosome-derived SSRs (BAC-SSRs), and 572 public SSRs and other markers covering a total distance of 1245.9 cM of the B. rapa genome. Analysis of allelic diversity in 24 B. rapa germplasm using 234 mapped EST-SSR markers showed amplification of 2 alleles by majority of EST-SSRs, although amplification of alleles ranging from 2 to 8 was found. Transferability analysis of 167 EST-SSRs in 35 species belonging to cultivated and wild brassica relatives showed 42.51% (Sysimprium leteum) to 100% (B. carinata, B. juncea, and B. napus) amplification. Our newly developed EST-SSRs and high-density linkage map based on highly transferable genic markers would facilitate the molecular mapping of quantitative trait loci and the positional cloning of specific genes, in addition to marker-assisted selection and comparative genomic studies of B. rapa with other related species.
- Published
- 2011
27. Postmodernism, or an Abuse of Concepts
- Author
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Van Dan Nguyen
- Subjects
Psychoanalysis ,Sociology ,Social science ,Postmodernism - Published
- 2008
28. A12 Field evaluation of spatial repellency of metofluthrin-impregnated latticework plastic strips against Aedes aegypti (L.) in Do Son, Hai Phong city, Vietnam(The 59th Annual Meeting of the Japan Society of Medical Entomology and Zoology)
- Author
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H. Kawada, Y. Higa, Thi Yen Nguyen, Thuy Hoa Nguyen, Minh Sang Truong, Van Dan Nguyen, Ngoc Dinh Pham, and M. Takagi
- Published
- 2007
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