17 results on '"Nguyen, TKT"'
Search Results
2. The impact of targeted malaria elimination with mass drug administrations on falciparum malaria in Southeast Asia: A cluster randomised trial
- Author
-
Beeson, JG, von Seidlein, L, Peto, TJ, Landier, J, Thuy-Nhien, N, Tripura, R, Phommasone, K, Pongvongsa, T, Lwin, KM, Keereecharoen, L, Kajeechiwa, L, Thwin, MM, Parker, DM, Wiladphaingern, J, Nosten, S, Proux, S, Corbel, V, Nguyen, T-V, Truong, LP-N, Do, HS, Pham, NH-T, Nguyen, TKT, Nguyen, TT, Le, TD, Dao, VH, Huynh, HQ, Nguon, C, Davoeung, C, Rekol, H, Adhikari, B, Henriques, G, Phongmany, P, Suangkanarat, P, Jeeyapant, A, Vihokhern, B, van der Pluijm, RW, Lubell, Y, White, LJ, Aguas, R, Promnarate, C, Sirithiranont, P, Malleret, B, Renia, L, Onsjo, C, Chan, XH, Chalk, J, Miotto, O, Patumrat, K, Chotivanich, K, Hanboonkunupakarn, B, Jittmala, P, Kaehler, N, Cheah, PY, Pell, C, Dhorda, M, Imwong, M, Snounou, G, Mukaka, M, Peerawaranun, P, Lee, SJ, Simpson, JA, Pukrittayakamee, S, Singhasivanon, P, Grobusch, MP, Cobelens, F, Smithuis, F, Newton, PN, Thwaites, GE, Day, NPJ, Mayxay, M, Tran, TH, Nosten, FH, Dondorp, AM, White, NJ, Beeson, JG, von Seidlein, L, Peto, TJ, Landier, J, Thuy-Nhien, N, Tripura, R, Phommasone, K, Pongvongsa, T, Lwin, KM, Keereecharoen, L, Kajeechiwa, L, Thwin, MM, Parker, DM, Wiladphaingern, J, Nosten, S, Proux, S, Corbel, V, Nguyen, T-V, Truong, LP-N, Do, HS, Pham, NH-T, Nguyen, TKT, Nguyen, TT, Le, TD, Dao, VH, Huynh, HQ, Nguon, C, Davoeung, C, Rekol, H, Adhikari, B, Henriques, G, Phongmany, P, Suangkanarat, P, Jeeyapant, A, Vihokhern, B, van der Pluijm, RW, Lubell, Y, White, LJ, Aguas, R, Promnarate, C, Sirithiranont, P, Malleret, B, Renia, L, Onsjo, C, Chan, XH, Chalk, J, Miotto, O, Patumrat, K, Chotivanich, K, Hanboonkunupakarn, B, Jittmala, P, Kaehler, N, Cheah, PY, Pell, C, Dhorda, M, Imwong, M, Snounou, G, Mukaka, M, Peerawaranun, P, Lee, SJ, Simpson, JA, Pukrittayakamee, S, Singhasivanon, P, Grobusch, MP, Cobelens, F, Smithuis, F, Newton, PN, Thwaites, GE, Day, NPJ, Mayxay, M, Tran, TH, Nosten, FH, Dondorp, AM, and White, NJ
- Abstract
BACKGROUND: The emergence and spread of multidrug-resistant Plasmodium falciparum in the Greater Mekong Subregion (GMS) threatens global malaria elimination efforts. Mass drug administration (MDA), the presumptive antimalarial treatment of an entire population to clear the subclinical parasite reservoir, is a strategy to accelerate malaria elimination. We report a cluster randomised trial to assess the effectiveness of dihydroartemisinin-piperaquine (DP) MDA in reducing falciparum malaria incidence and prevalence in 16 remote village populations in Myanmar, Vietnam, Cambodia, and the Lao People's Democratic Republic, where artemisinin resistance is prevalent. METHODS AND FINDINGS: After establishing vector control and community-based case management and following intensive community engagement, we used restricted randomisation within village pairs to select 8 villages to receive early DP MDA and 8 villages as controls for 12 months, after which the control villages received deferred DP MDA. The MDA comprised 3 monthly rounds of 3 daily doses of DP and, except in Cambodia, a single low dose of primaquine. We conducted exhaustive cross-sectional surveys of the entire population of each village at quarterly intervals using ultrasensitive quantitative PCR to detect Plasmodium infections. The study was conducted between May 2013 and July 2017. The investigators randomised 16 villages that had a total of 8,445 residents at the start of the study. Of these 8,445 residents, 4,135 (49%) residents living in 8 villages, plus an additional 288 newcomers to the villages, were randomised to receive early MDA; 3,790 out of the 4,423 (86%) participated in at least 1 MDA round, and 2,520 out of the 4,423 (57%) participated in all 3 rounds. The primary outcome, P. falciparum prevalence by month 3 (M3), fell by 92% (from 5.1% [171/3,340] to 0.4% [12/2,828]) in early MDA villages and by 29% (from 7.2% [246/3,405] to 5.1% [155/3,057]) in control villages. Over the following 9 months, th
- Published
- 2019
3. Bacterial risk factors for treatment failure and relapse among patients with isoniazid resistant tuberculosis
- Author
-
Phan, VKT, Dang, TMH, Nguyen, TH, Day, J, Dunstan, S, Nguyen, TQN, Vo, SK, Nguyen, HL, Nguyen, HD, Nguyen, TNL, Nguyen, TT, Nguyen, NL, Pham, TTL, Dao, CD, Nguyen, TKT, Nguyen, VH, Nguyen, VN, Truong, ND, Hoang, QM, Nguyen, VT, Farrar, J, Caws, M, Phan, VKT, Dang, TMH, Nguyen, TH, Day, J, Dunstan, S, Nguyen, TQN, Vo, SK, Nguyen, HL, Nguyen, HD, Nguyen, TNL, Nguyen, TT, Nguyen, NL, Pham, TTL, Dao, CD, Nguyen, TKT, Nguyen, VH, Nguyen, VN, Truong, ND, Hoang, QM, Nguyen, VT, Farrar, J, and Caws, M
- Abstract
BACKGROUND: Drug resistant tuberculosis (TB) is increasing in prevalence worldwide. Treatment failure and relapse is known to be high for patients with isoniazid resistant TB treated with standard first line regimens. However, risk factors for unfavourable outcomes and the optimal treatment regimen for isoniazid resistant TB are unknown. This cohort study was conducted when Vietnam used the eight month first line treatment regimen and examined risk factors for failure/relapse among patients with isoniazid resistant TB. METHODS: Between December 2008 and June 2011 2090 consecutive HIV-negative adults (≥18 years of age) with new smear positive pulmonary TB presenting at participating district TB units in Ho Chi Minh City were recruited. Participants with isoniazid resistant TB identified by Microscopic Observation Drug Susceptibility (MODS) had extended follow-up for 2 years with mycobacterial culture to test for relapse. MGIT drug susceptibility testing confirmed 239 participants with isoniazid resistant, rifampicin susceptible TB. Bacterial and demographic factors were analysed for association with treatment failure and relapse. RESULTS: Using only routine programmatic sputum smear microscopy for assessment, (months 2, 5 and 8) 30/239 (12.6%) had an unfavourable outcome by WHO criteria. Thirty-nine patients were additionally detected with unfavourable outcomes during 2 year follow up, giving a total of 69/239 (28.9%) of isoniazid (INH) resistant cases with unfavourable outcome by 2 years of follow-up. Beijing lineage was the only factor significantly associated with unfavourable outcome among INH-resistant TB cases during 2 years of follow-up. (adjusted OR = 3.16 [1.54-6.47], P = 0.002). CONCLUSION: One third of isoniazid resistant TB cases suffered failure/relapse within 2 years under the old eight month regimen. Over half of these cases were not identified by standard WHO recommended treatment monitoring. Intensified research on early identification and optimal re
- Published
- 2018
4. Testing biological actions of medicinal plants from northern Vietnam on zebrafish embryos and larvae: Developmental, behavioral, and putative therapeutical effects.
- Author
-
Tran MH, Nguyen TVA, Do HG, Kieu TK, Nguyen TKT, Le HD, Guerrero-Limon G, Massoz L, Nivelle R, Zappia J, Pham HT, Nguyen LT, and Muller M
- Subjects
- Animals, Embryo, Nonmammalian, Larva, Plant Extracts pharmacology, Plant Extracts chemistry, Vietnam, Zebrafish genetics, Plants, Medicinal
- Abstract
Evaluating the risks and benefits of using traditional medicinal plants is of utmost importance for a huge fraction of the human population, in particular in Northern Vietnam. Zebrafish are increasingly used as a simple vertebrate model for testing toxic and physiological effects of compounds, especially on development. Here, we tested 12 ethanolic extracts from popular medicinal plants collected in northern Vietnam for their effects on zebrafish survival and development during the first 4 days after fertilization. We characterized more in detail their effects on epiboly, hatching, growth, necrosis, body curvature, angiogenesis, skeletal development and mostly increased movement behavior. Finally, we confirm the effect on epiboly caused by the Mahonia bealei extract by staining the actin filaments and performing whole genome gene expression analysis. Further, we show that this extract also inhibits cell migration of mouse embryo fibroblasts. Finally, we analyzed the chemical composition of the Mahonia bealei extract and test the effects of its major components. In conclusion, we show that traditional medicinal plant extracts are able to affect zebrafish early life stage development to various degrees. In addition, we show that an extract causing delay in epiboly also inhibits mammalian cell migration, suggesting that this effect may serve as a preliminary test for identifying extracts that inhibit cancer metastasis., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Tran et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
- Published
- 2023
- Full Text
- View/download PDF
5. Modulation of TDM-induced granuloma pathology by human lactoferrin: a persistent effect in mice.
- Author
-
Actor JK, Nguyen TKT, Wasik-Smietana A, and Kruzel ML
- Subjects
- Animals, Humans, Mice, Mycobacterium tuberculosis metabolism, Cord Factors metabolism, Cord Factors toxicity, Lactoferrin therapeutic use, Granuloma, Respiratory Tract chemically induced, Granuloma, Respiratory Tract drug therapy, Lung Diseases chemically induced, Lung Diseases drug therapy
- Abstract
Lactoferrin (LTF), an iron binding protein, is known to exhibit immune modulatory effects on pulmonary pathology during insult-induced models of primary Mycobacterium tuberculosis (Mtb) infection. The effects of LTF correlate with modulation of the immune related development of the pathology, and altering of the histological nature of the physically compact and dense lung granuloma in mice. Specifically, a recombinant human version of LTF limits immediate progression of granulomatous severity following administration of the Mtb cell wall mycolic acid, trehalose 6,6'-dimycolate (TDM), in part through reduced pro-inflammatory responses known to control these events. This current study investigates a limited course of LTF to modulate not only initiation, but also maintenance and resolution of pathology post development of the granulomatous response in mice. Comparison is made to a fusion of LTF with the Fc domain of IgG2 (FcLTF), which is known to extend LTF half-life in circulation. TDM induced granulomas were examined at extended times post insult (day 7 and 14). Both LTF and the novel FcLTF exerted sustained effects on lung granuloma pathology. Reduction of pulmonary pro-inflammatory cytokines TNF-α and IL-1β occurred, correlating with reduced pathology. Increase in IL-6, known to regulate granuloma maintenance, was also seen with the LTFs. The FcLTF demonstrated greater impact than the recombinant LTF, and was superior in limiting damage to pulmonary tissues while limiting residual inflammatory cytokine production., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)
- Published
- 2023
- Full Text
- View/download PDF
6. Norms of soft tissue cephalometric in the 18-25 age demography in Vietnam.
- Author
-
Le LN, Do TT, Le PKV, Huynh DV, and Nguyen TKT
- Abstract
Background and Purpose: The soft-tissue layer and facial skeleton influence the harmony and equilibrium of the face. The evaluation of the patient's structural and soft-tissue features is one of the most crucial steps in preparing for the diagnosis and treatment of oral-maxillofacial orthodontics. Clinicians can intervene with the proper treatment at the proper time to achieve the best results by being aware of the traits and variations of soft tissue at various developmental stages and in various races. To obtain a consistent treatment result in terms of function and aesthetically pleasing results, patients, and forecast, the growth that may take place after the orthopedic therapy has concluded., Objective: To examine the soft-tissue features of the oral-maxillofacial area in Vietnamese adults (aged 18-25 years) by evaluating cephalometric radiographs., Materials and Methods: In a cross-sectional descriptive study, 85 students from Can Tho University of Medicine and Pharmacy took part. Students' lateral cephalograms were taken in compliance with the sample requirements., Results: Men's lip protrusion (4.30 ± 0.71) was higher than women's (3.88 ± 0.97) ( P = 0.024 <.05) and men's (-4.88 ± 0.93) chin lip groove depth was higher than women's (-4.24 ± 0.93) ( P = 0.002), both with a P value of. 05., Conclusions: The study identified a statistically significant difference in the protrusion of the top lip and the depth of the cleft lip between the male and female, demonstrating that the soft-tissue features of Vietnamese students were distinct from those of other races., Competing Interests: There are no conflicts of interest., (Copyright: © 2023 Journal of Orthodontic Science.)
- Published
- 2023
- Full Text
- View/download PDF
7. A Clinically Oriented antimicrobial Resistance surveillance Network (ACORN): pilot implementation in three countries in Southeast Asia, 2019-2020.
- Author
-
van Doorn HR, Miliya T, Douangnouvong A, Ta Thi Dieu N, Soputhy C, Lem M, Chommanam D, Keoluangkhot V, Soumphonphakdy B, Rassavong K, Thanadabouth K, Sayarath M, Chansamouth V, Vu MD, Dong PK, Dang VD, Tran VB, Do TKY, Ninh TN, Nguyen HL, Kim NH, Prak S, Vongsouvath M, Van DT, Nguyen TKT, Nguyen HK, Hamers RL, Ling C, Roberts T, Waithira N, Wannapinij P, Vu TVD, Celhay O, Ngoun C, Vongphachanh S, Pham NT, Ashley EA, and Turner P
- Abstract
Background: Case-based surveillance of antimicrobial resistance (AMR) provides more actionable data than isolate- or sample-based surveillance. We developed A Clinically Oriented antimicrobial Resistance surveillance Network (ACORN) as a lightweight but comprehensive platform, in which we combine clinical data collection with diagnostic stewardship, microbiological data collection and visualisation of the linked clinical-microbiology dataset. Data are compatible with WHO GLASS surveillance and can be stratified by syndrome and other metadata. Summary metrics can be visualised and fed back directly for clinical decision-making and to inform local treatment guidelines and national policy. Methods: An ACORN pilot was implemented in three hospitals in Southeast Asia (1 paediatric, 2 general) to collect clinical and microbiological data from patients with community- or hospital-acquired pneumonia, sepsis, or meningitis. The implementation package included tools to capture site and laboratory capacity information, guidelines on diagnostic stewardship, and a web-based data visualisation and analysis platform. Results: Between December 2019 and October 2020, 2294 patients were enrolled with 2464 discrete infection episodes (1786 community-acquired, 518 healthcare-associated and 160 hospital-acquired). Overall, 28-day mortality was 8.7%. Third generation cephalosporin resistance was identified in 54.2% (39/72) of E. coli and 38.7% (12/31) of K. pneumoniae isolates . Almost a quarter of S. aureus isolates were methicillin resistant (23.0%, 14/61). 290/2464 episodes could be linked to a pathogen, highlighting the level of enrolment required to achieve an acceptable volume of isolate data. However, the combination with clinical metadata allowed for more nuanced interpretation and immediate feedback of results. Conclusions: ACORN was technically feasible to implement and acceptable at site level. With minor changes from lessons learned during the pilot ACORN is now being scaled up and implemented in 15 hospitals in 9 low- and middle-income countries to generate sufficient case-based data to determine incidence, outcomes, and susceptibility of target pathogens among patients with infectious syndromes., Competing Interests: Competing interests: I am a board member of Wellcome SEDRIC, (Copyright: © 2022 van Doorn HR et al.)
- Published
- 2022
- Full Text
- View/download PDF
8. Notes on Culturable Endophytic Microorganisms Isolated from 14 Medicinal Plants in Vietnam: A Diversity Analysis to Predict the Host-Microbe Correlations.
- Author
-
Tran HM, Nguyen DTT, Mai NT, Do HT, Nguyen TKT, Nguyen TKN, Muller M, Nguyen HQ, and Pham HT
- Subjects
- Bacteria genetics, Endophytes, Fungi, Vietnam, Plants, Medicinal microbiology
- Abstract
Endophytes can generate a cornucopia of marvelous bioactive secondary metabolites useful for mankind but their biodiversity and associations with host plants are still elusive. In this study, we explored the culturable endophytic microorganisms associated with 14 medicinal plants that are of high socio-economic value and/or reportedly endemic to northern Vietnam. Specifically, we isolated the endophytic microorganisms by applying surface sterilization methods and identified them based on morphological and rDNA sequence analyses. Agglomerative Hierarchical Clustering (AHC) and Principal Component Analysis (PCA) were used to analyze the correlations between the taxonomic affiliations of the culturable endophytes and the characteristics of their hosts. Most of the culturable endophytes obtained were bacteria (80), and few of those were actinomycetes (15) and fungi (8). Many of them are reported to be endophytes of medicinal plants for the first time. A number of plants (5) are also reported for the first time to contain microbial endophytes, while some plants with powerful pharmaceutical potential harbor unique endophytes. Furthermore, our results reveal a strikingly close relation between the compositions of bacterial and fungal isolates from plants having anti-bacterial activity and those from plants having anti-inflammatory activity, or between the compositions of the microbial endophytic isolates from plants having anti-cancer activity and those from plants having antioxidant activity. Altogether, the results provide new findings which can be inspiring for further in-depth studies to explore and exploit the relationships between medicinal plants and their associated endophytes in northern Vietnam and world-wide., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
- Published
- 2022
- Full Text
- View/download PDF
9. Recombinant Human Lactoferrin Reduces Inflammation and Increases Fluoroquinolone Penetration to Primary Granulomas During Mycobacterial Infection of C57Bl/6 Mice.
- Author
-
Nguyen TKT, Niaz Z, Kruzel ML, and Actor JK
- Subjects
- Animals, Fluoroquinolones adverse effects, Fluoroquinolones metabolism, Granuloma chemically induced, Granuloma drug therapy, Granuloma metabolism, Humans, Inflammation, Mice, Mice, Inbred C57BL, Lactoferrin metabolism, Mycobacterium tuberculosis
- Abstract
Infection with Mycobacterium tuberculosis (Mtb) results in the primary formation of a densely packed inflammatory foci that limits entry of therapeutic agents into pulmonary sites where organisms reside. No current therapeutic regimens exist that modulate host immune responses to permit increased drug penetration to regions of pathological damage during tuberculosis disease. Lactoferrin is a natural iron-binding protein previously demonstrated to modulate inflammation and granuloma cohesiveness, while maintaining control of pathogenic burden. Studies were designed to examine recombinant human lactoferrin (rHLF) to modulate histological progression of Mtb-induced pathology in a non-necrotic model using C57Bl/6 mice. The rHLF was oral administered at times corresponding to initiation of primary granulomatous response, or during granuloma maintenance. Treatment with rHLF demonstrated significant reduction in size of primary inflammatory foci following Mtb challenge, and permitted penetration of ofloxacin fluoroquinolone therapeutic to sites of pathological disruption where activated (foamy) macrophages reside. Increased drug penetration was accompanied by retention of endothelial cell integrity. Immunohistochemistry revealed altered patterns of M1-like and M2-like phenotypic cell localization post infectious challenge, with increased presence of M2-like markers found evenly distributed throughout regions of pulmonary inflammatory foci in rHLF-treated mice., (© 2022. L. Hirszfeld Institute of Immunology and Experimental Therapy, Wroclaw, Poland.)
- Published
- 2022
- Full Text
- View/download PDF
10. Progression of liver fibrosis and associated factors among chronic hepatitis B patients at a general hospital in Northern Vietnam.
- Author
-
Luu NM, Nguyen TKT, Vu TT, Dinh TS, Luu NH, Do TTT, Nguyen VS, Ha TBV, Nguyen DC, Tran TH, Phung TTH, Duong XP, Khuong QL, Nguyen TTT, Saw YM, Hoang TNA, and Nguyen TN
- Subjects
- Aspartate Aminotransferases, Bayes Theorem, Biomarkers, Hospitals, General, Humans, Liver Cirrhosis epidemiology, Longitudinal Studies, Platelet Count, Retrospective Studies, Severity of Illness Index, Vietnam epidemiology, Hepatitis B, Chronic diagnosis, Hepatitis B, Chronic drug therapy, Hepatitis B, Chronic epidemiology
- Abstract
Evaluation of liver fibrosis is necessary to make the therapeutic decision and assess the prognosis of CHB patients. The current study aimed to describe the progression and identify some influencing factors in patients with chronic hepatitis B at a General Hospital in Northern Vietnam. The longitudinal study included 55 eligible subjects diagnosed Hepatitis-B-virus. Dependent variable was the aspartate aminotransferase/platelet ratio index and we collected some demographic variables and disease related and behaviour variables. Bayesian Model Averaging was used to select variables into model. Mixed-effect linear models were used to evaluate the change of the aspartate aminotransferase/platelet ratio index over time and identify related factors. the aspartate aminotransferase/platelet ratio index differences between examinations, age of participants, working status were statistically significant. This pattern indicated that the average the aspartate aminotransferase/platelet ratio index of the population decreased by 0.005 (95% CI=-0.009; -0.001) after each patient's visit, and increased by 0.013 if the patient's age increased by 1 year (95% CI=0.005; 0.0219). For non-working patients, the aspartate aminotransferase/platelet ratio index was lower, coefficient was -0.054 (95% CI=-0.108; 0.001). Other variables such as gender, education level, time for disease detection, drinking tea, alcohol consumption, forgetting to take medicine and the aspartate aminotransferase/platelet ratio index were not significantly different. The study showed that the majority of study subjects had average the aspartate aminotransferase/platelet ratio index, and were relatively well controlled and treated during the study. Age and working status are factors that influence the the aspartate aminotransferase/platelet ratio index., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper.
- Published
- 2022
- Full Text
- View/download PDF
11. Flexible, affordable and environmentally sustainable solar vapor generation based on ferric tannate/bacterial cellulose composite for efficient desalination solutions.
- Author
-
Nguyen TKT, Dao QK, Tanaka D, Nghiem LHT, Nguyen MV, Nguyen ZH, and Pham TT
- Abstract
Desalination by solar steam generation (SSG) system is a green technology to produce pure water, which can address the issue of water scarcity. A novel photothermal material for the SSG system was fabricated by immersing bacterial cellulose (BC) sequentially into tannic acid (TA) and iron(iii) (Fe
3+ ) solutions. Surface analysis of the resulting BC-TA-Fe3+ (BTF) material showed that coordination nanocomplexes between Fe3+ and hydroxyl groups of TA were formed on the surface of cellulose nanofibers. BTF material exhibited high sunlight absorption (∼95%), hydrophilic, self-cleaning properties, and excellent structural stability. SSG systems based on BTF had an evaporation efficiency of 91% and an evaporation rate of 1.56 kg m-2 h-1 under 1 sun illumination. Then, an efficient desalination device based on the larger-scale BTF material was fabricated to produce freshwater, the amount of freshwater per day was 5.6 kg m-2 on a sunny day. BTF material, thus, showed great potential in seawater desalination applications along with simple, versatile, scalable, and affordable fabrication methods., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)- Published
- 2021
- Full Text
- View/download PDF
12. Lactoferrin reduces mycobacterial M1-type inflammation induced with trehalose 6,6'-dimycolate and facilitates the entry of fluoroquinolone into granulomas.
- Author
-
Nguyen TKT, Niaz Z, d'Aigle J, Hwang SA, Kruzel ML, and Actor JK
- Subjects
- Animals, Cord Factors, Female, Fluoroquinolones, Granuloma chemically induced, Humans, Lactoferrin chemistry, Mice, Mice, Inbred C57BL, Recombinant Proteins chemistry, Recombinant Proteins metabolism, Granuloma metabolism, Inflammation metabolism, Lactoferrin metabolism, Mycobacterium metabolism
- Abstract
Primary infection with Mycobacterium tuberculosis ( Mtb ) results in the formation of a densely packed granulomatous response that essentially limits the entry and efficacy of immune effector cells. Furthermore, the physical nature of the granuloma does not readily permit the entry of therapeutic agents to sites where organisms reside. The Mtb cell wall mycolic acid, trehalose 6,6'-dimycolate (TDM), is a physiologically relevant molecule for modelling macrophage-mediated events during the establishment of the tuberculosis-induced granuloma pathogenesis. At present, there are no treatments for tuberculosis that focus on modulating the host's immune responses. Previous studies showed that lactoferrin (LF), a natural iron-binding protein proven to modulate inflammation, can ameliorate the cohesiveness of granuloma. This led to a series of studies that further examined the effects of recombinant human LF (rHLF) on the histological progression of TDM-induced pathology. Treatment with rHLF demonstrated significant reduction in size and number of inflammatory foci following injections of TDM, together with reduced levels pulmonary pro-inflammatory cytokines TNF-α and IL-1β. LF facilitated greater penetration of fluoroquinolone to the sites of pathology. Mice treated with TDM alone demonstrated exclusion of ofloxacin to regions of inflammatory response, whereas the animals treated with rHLF demonstrated increased penetration to inflammatory foci. Finally, recent findings support the hypothesis that this mycobacterial mycolic acid can specifically recruit M1-like polarized macrophages; rHLF treatment was shown to limit the level of this M1-like phenotypic recruitment, corresponding highly with decreased inflammatory response.
- Published
- 2021
- Full Text
- View/download PDF
13. Simple design of efficient broadband multifunctional polarization converter for X-band applications.
- Author
-
Nguyen TKT, Nguyen TM, Nguyen HQ, Cao TN, Le DT, Bui XK, Bui ST, Truong CL, Vu DL, and Nguyen TQH
- Abstract
A simple design of a broadband multifunctional polarization converter using an anisotropic metasurface for X-band application is proposed. The proposed polarization converter consists of a periodic array of the two-corner-cut square patch resonators based on the FR-4 substrate that achieves both cross-polarization and linear-to-circular polarization conversions. The simulated results show that the polarization converter displays the linear cross-polarization conversion in the frequency range from 8 to 12 GHz with the polarization conversion efficiency above 90%. The efficiency is kept higher than 80% with wide incident angle up to 45°. Moreover, the proposed design achieves the linear-to-circular polarization conversion at two frequency bands of 7.42-7.6 GHz and 13-13.56 GHz. A prototype of the proposed polarization converter is fabricated and measured, showing a good agreement between the measured and simulated results. The proposed polarization converter exhibits excellent performances such as simple structure, multifunctional property, and large cost-efficient bandwidth and wide incident angle insensitivity in the linear cross polarization conversion, which can be useful for X-band applications. Furthermore, this structure can be extended to design broadband polarization converters in other frequency bands.
- Published
- 2021
- Full Text
- View/download PDF
14. Thermoelectric Transport in a Three-Channel Charge Kondo Circuit.
- Author
-
Nguyen TKT and Kiselev MN
- Abstract
We theoretically investigate the thermoelectric transport through a circuit implementation of the three-channel charge Kondo model quantum simulator [Z. Iftikhar et al., Science 360, 1315 (2018)SCIEAS0036-807510.1126/science.aan5592]. The universal temperature scaling law of the Seebeck coefficient is computed perturbatively approaching the non-Fermi liquid strong coupling fixed point using the Abelian bosonization technique. The predicted T^{1/3}logT scaling behavior of the thermoelectric power sheds light on the properties of Z_{3} emerging parafermions and gives access to exploring prefractionalized zero modes in the quantum transport experiments. We discuss a generalization of approach for investigating a multichannel Kondo problem with emergent Z_{N}→Z_{M} crossovers between "weak" non-Fermi liquid regimes corresponding to different low-temperature fixed points.
- Published
- 2020
- Full Text
- View/download PDF
15. Mycobacterial Trehalose 6,6'-Dimycolate-Induced M1-Type Inflammation.
- Author
-
Nguyen TKT, d'Aigle J, Chinea L, Niaz Z, Hunter RL, Hwang SA, and Actor JK
- Subjects
- Animals, Female, Granuloma chemically induced, Granuloma metabolism, Macrophages drug effects, Macrophages metabolism, Mice, Mice, Inbred C57BL, Pneumonia chemically induced, Pneumonia metabolism, Adjuvants, Immunologic toxicity, Cord Factors toxicity, Granuloma pathology, Inflammation Mediators metabolism, Macrophages pathology, Mycobacterium metabolism, Pneumonia pathology
- Abstract
Murine models of Mycobacterium tuberculosis (Mtb) infection demonstrate progression of M1-like (proinflammatory) and M2-like (anti-inflammatory) macrophage morphology following primary granuloma formation. The Mtb cell wall cording factor, trehalose 6,6'-dimycolate (TDM), is a physiologically relevant and useful molecule for modeling early macrophage-mediated events during establishment of the tuberculosis-induced granuloma pathogenesis. Here, it is shown that TDM is a major driver of the early M1-like macrophage response as seen during initiation of the granulomas of primary pathology. Proinflammatory cytokines tumor necrosis factor-α, IL-1β, IL-6, and IL-12p40 are produced in lung tissue after administration of TDM to mice. Furthermore, CD11b
+ CD45+ macrophages with a high surface expression of the M1-like markers CD38 and CD86 were found present in regions of pathology in lungs of mice at 7 days post-TDM introduction. Conversely, only low phenotypic marker expression of M2-like markers CD206 and EGR-2 were present on macrophages. These findings suggest that TDM plays a role in establishment of the M1-like shift in the microenvironment during primary tuberculosis., (Copyright © 2020 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)- Published
- 2020
- Full Text
- View/download PDF
16. Cost-effective capillary electrophoresis with contactless conductivity detection for quality control of beta-lactam antibiotics.
- Author
-
Nguyen TAH, Pham TNM, Le TB, Le DC, Tran TTP, Nguyen TQH, Nguyen TKT, Hauser PC, and Mai TD
- Subjects
- Hydrogen-Ion Concentration, Limit of Detection, Quality Control, Anti-Bacterial Agents analysis, Cost-Benefit Analysis, Electric Conductivity, Electrophoresis, Capillary economics, Electrophoresis, Capillary methods, beta-Lactams analysis
- Abstract
A simple and inexpensive approach for determination of various antimicrobial drugs using a purpose-made compact capillary electrophoresis (CE) instrument with capacitively coupled contactless conductivity detection (C
4 D) is reported. The objective of the work is to propose an affordable and easily-implemented tool for quality control and detection of counterfeiting of antibiotic formulations in resource constrained developing countries. The design of the purpose-made CE-C4 D system was improved according to the feedback from over 10 years of use of our previous instrument. CE-C4 D methods were for the first time developed to analyze β-lactam-based antibiotics commonly used in Vietnam, including single- β-lactam antibiotics (i.e. Cephalexin, Cefotaxime Sodium, Cefixime and Sulbactam) as well as β-lactams co-formulated with Sulbactam (i.e. Amoxicillin, Ampicillin, Cefoperazone and Sulbactam). Single β-lactam antibiotics were analyzed using a background electrolyte (BGE) composed of Tris/Ace (10 mM, pH 7.8) whereas β-lactam - Sulbactam combinations were simultaneously separated using a BGE containing Tris/Ace (10 mM, pH 7.5). The best achieved detection limits were 2.0 mg/L and 1.0 mg/L for these two groups, respectively. Good agreement between results obtained from CE-C4 D and standard confirmation methods (LCMS) was achieved, with a coefficient of determination, r2 , of 0.9991. The applicability of the developed CE-C4 D method was demonstrated for quality control of 24 β-lactam-based antimicrobial drugs available in Vietnam., (Copyright © 2019 Elsevier B.V. All rights reserved.)- Published
- 2019
- Full Text
- View/download PDF
17. Dental phenotypic shape variation supports a multiple dispersal model for anatomically modern humans in Southeast Asia.
- Author
-
Corny J, Galland M, Arzarello M, Bacon AM, Demeter F, Grimaud-Hervé D, Higham C, Matsumura H, Nguyen LC, Nguyen TKT, Nguyen V, Oxenham M, Sayavongkhamdy T, Sémah F, Shackelford LL, and Détroit F
- Subjects
- Anthropology, Physical, Asia, Southeastern, Humans, Mandible anatomy & histology, Population Dynamics, Biological Variation, Population, Human Migration, Molar anatomy & histology
- Abstract
The population history of anatomically modern humans (AMH) in Southeast Asia (SEA) is a highly debated topic. The impact of sea level variations related to the Last Glacial Maximum (LGM) and the Neolithic diffusion on past population dispersals are two key issues. We have investigated competing AMH dispersal hypotheses in SEA through the analysis of dental phenotype shape variation on the basis of very large archaeological samples employing two complementary approaches. We first explored the structure of between- and within-group shape variation of permanent human molar crowns. Second, we undertook a direct test of competing hypotheses through a modeling approach. Our results identify a significant LGM-mediated AMH expansion and a strong biological impact of the spread of Neolithic farmers into SEA during the Holocene. The present work thus favors a "multiple AMH dispersal" hypothesis for the population history of SEA, reconciling phenotypic and recent genomic data., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.