53 results on '"Vu QV"'
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2. Porphyrin derivatives inhibit tumor necrosis factor α-induced gene expression and reduce the expression and increase the cross-linked forms of cellular components of the nuclear factor κB signaling pathway.
- Author
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Vu QV, Vu NT, Baba K, Sasaki S, Tamura R, Morimoto K, Hirano H, Osada H, and Kataoka T
- Subjects
- Humans, A549 Cells, E-Selectin metabolism, E-Selectin genetics, Gene Expression Regulation drug effects, Signal Transduction drug effects, Tumor Necrosis Factor-alpha metabolism, Intercellular Adhesion Molecule-1 metabolism, Intercellular Adhesion Molecule-1 genetics, NF-kappa B metabolism, Porphyrins pharmacology, Porphyrins chemistry
- Abstract
The transcription factor nuclear factor κB (NF-κB) is activated by proinflammatory cytokines, such as tumor necrosis factor α (TNF-α) and Toll-like receptor (TLR) ligands. Screening of NPDepo chemical libraries identified porphyrin derivatives as anti-inflammatory compounds that strongly inhibited the up-regulation of intercellular adhesion molecule-1 (ICAM-1) expression induced by TNF-α, interleukin-1α, the TLR3 ligand, and TLR4 ligand in human umbilical vein endothelial cells. In the present study, the mechanisms of action of porphyrin derivatives were further elucidated using human lung adenocarcinoma A549 cells. Porphyrin derivatives, i.e., dimethyl-2,7,12,18-tetramethyl-3,8-di(1-methoxyethyl)-21H,23H-porphine-13,17-dipropionate (1) and pheophorbide a (2), inhibited TNF-α-induced ICAM-1 expression and decreased the TNF-α-induced transcription of ICAM-1, vascular cell adhesion molecule-1, and E-selectin genes. 1 and 2 reduced the expression of the NF-κB subunit RelA protein for 1 h, which was not rescued by the inhibition of proteasome- and lysosome-dependent protein degradation. In addition, 1 and 2 decreased the expression of multiple components of the TNF receptor 1 complex, and this was accompanied by the appearance of their cross-linked forms. As common components of the NF-κB signaling pathway, 1 and 2 also cross-linked the α, β, and γ subunits of the inhibitor of NF-κB kinase complex and the NF-κB subunits RelA and p50. Cellular protein synthesis was prevented by 2, but not by 1. Therefore, the present results indicate that porphyrin derivative 1 reduced the expression and increased the cross-linked forms of cellular components required for the NF-κB signaling pathway without affecting global protein synthesis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
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3. Successful surgical interventions for a giant and complicated myoepithelial carcinoma: a case report.
- Author
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Vu QV, Hoang TT, Tran VA, Tong TH, and Nguyen HH
- Abstract
Ethmoid myoepithelial carcinoma is a rare tumor, with only 14 cases reported to date. This report discusses the largest tumor of this type ever recorded in the ethmoid region. The tumor caused extensive damage to facial structures, complicating treatment. The patient's age and comorbidities increased the risk of intraoperative bleeding, presenting challenges to the complete removal of the tumor and the reconstruction of the damaged structures. To reduce the risk of intraoperative hemorrhage, shorten the surgery time, and manage potential heartrelated complications, arterial embolization was performed using gelatin sponges and coils. Definitive surgery was then carried out using a skin flap and mucosal flap to successfully reconstruct the defect. Postoperative radiotherapy was deemed unnecessary. The patient recovered well, with a satisfactory aesthetic outcome. No recurrence was observed during a 3-year follow-up period.
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- 2024
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4. The annual economic burden incurred by heart failure patients in Vietnam: a retrospective analysis.
- Author
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Dao TD, Tran HTB, Vu QV, Nguyen HTT, Nguyen PV, and Vo TQ
- Abstract
Introduction: Heart failure (HF) is a chronic condition associated with substantial mortality and hospitalisation, resulting in costly inpatient visits. The healthcare systems of several countries, including Vietnam, experience considerable difficulty in dealing with the enormous fiscal burden presented by HF. This study aims to analyse the direct medical costs associated with HF inpatient treatment from the hospital perspective., Materials and Methods: This study retrospectively analysed the electronic medical records of patients diagnosed with HF from 2018 to 2021 at Military Hospital 175 in Vietnam. The sample consisted of 906 hospitalised patients (mean age: 71.2 ± 14.1 years). The financial impact of HF was assessed by examining the direct medical expenses incurred by the healthcare system, and the costs of pharmaceutical categories used in treatment were explored., Results: The cumulative economic burden of HF from 2018 to 2021 was US$1,068,870, with annual costs ranging from US$201,670 to US$443,831. Health insurance covered 72.7% of these costs. Medications and infusions, and medical supplies accounted for the largest expenses, at 29.8% and 22.1%, respectively. The medication HF group accounted for 13.01% of these expenses, of which the costliest medications included nitrates (2.57%), angiotensin II receptor blockers (0.51%), ivabradine (0.39%), diuretics (0.24%), and mineralocorticoid receptor antagonists (0.23%). Comorbidities and the length of hospital stay significantly influenced annual treatment costs., Conclusion: The study reveals that HF significantly impacts Vietnam's healthcare system and citizens, requiring a comprehensive understanding of its financial implications and efficient management of medical resources for those diagnosed. This study highlights the substantial economic burden of HF on Vietnam's healthcare system, with medication costs, particularly antithrombotic drugs, representing the largest expense. Most healthcare costs were covered by health insurance, and expenses were significantly influenced by comorbidity and length of hospital stay. These findings can inform healthcare policy, resource allocation and optimise management strategies in Vietnam., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)
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- 2024
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5. Structure-Activity Relationship of Oleanane-Type Pentacyclic Triterpenoids on Nuclear Factor κB Activation and Intracellular Trafficking and N -Linked Glycosylation of Intercellular Adhesion Molecule-1.
- Author
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Nakano K, Yokota Y, Vu QV, Lagravinese F, and Kataoka T
- Subjects
- Humans, Glycosylation, Structure-Activity Relationship, A549 Cells, Signal Transduction drug effects, Cell Survival drug effects, Intercellular Adhesion Molecule-1 metabolism, NF-kappa B metabolism, Oleanolic Acid pharmacology, Oleanolic Acid analogs & derivatives, Oleanolic Acid chemistry, Protein Transport drug effects, Pentacyclic Triterpenes pharmacology, Pentacyclic Triterpenes chemistry, Triterpenes pharmacology, Triterpenes chemistry
- Abstract
In our previous study, two oleanane-type pentacyclic triterpenoids (oleanolic acid and maslinic acid) were reported to affect the N -glycosylation and intracellular trafficking of intercellular adhesion molecule-1 (ICAM-1). The present study was aimed at investigating the structure-activity relationship of 13 oleanane-type natural triterpenoids with respect to the nuclear factor κB (NF-κB) signaling pathway and the expression, intracellular trafficking, and N -glycosylation of the ICAM-1 protein in human lung adenocarcinoma A549 cells. Hederagenin, echinocystic acid, erythrodiol, and maslinic acid, which all possess two hydroxyl groups, decreased the viability of A549 cells. Celastrol and pristimerin, both of which possess an α , β -unsaturated carbonyl group, decreased cell viability but more strongly inhibited the interleukin-1α-induced NF-κB signaling pathway. Oleanolic acid, moronic acid, and glycyrrhetinic acid interfered with N -glycosylation without affecting the cell surface expression of the ICAM-1 protein. In contrast, α -boswellic acid and maslinic acid interfered with the N -glycosylation of the ICAM-1 protein, which resulted in the accumulation of high-mannose-type N -glycans. Among the oleanane-type triterpenoids tested, α -boswellic acid and maslinic acid uniquely interfered with the intracellular trafficking and N -glycosylation of glycoproteins.
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- 2024
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6. Sesquiterpene Lactones Containing an α-Methylene-γ-Lactone Moiety Selectively Down-Regulate the Expression of Tumor Necrosis Factor Receptor 1 by Promoting Its Ectodomain Shedding in Human Lung Adenocarcinoma A549 Cells.
- Author
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Vu QV, Sayama S, Ando M, and Kataoka T
- Subjects
- Humans, A549 Cells, Adenocarcinoma of Lung metabolism, Adenocarcinoma of Lung drug therapy, Adenocarcinoma of Lung pathology, Gene Expression Regulation, Neoplastic drug effects, Lung Neoplasms metabolism, Lung Neoplasms drug therapy, Lung Neoplasms pathology, NF-kappa B metabolism, Sesquiterpenes, Eudesmane pharmacology, Sesquiterpenes, Eudesmane chemistry, Signal Transduction drug effects, Structure-Activity Relationship, Down-Regulation drug effects, Lactones metabolism, Receptors, Tumor Necrosis Factor, Type I metabolism, Sesquiterpenes pharmacology, Sesquiterpenes chemistry
- Abstract
Alantolactone is a eudesmane-type sesquiterpene lactone containing an α-methylene-γ-lactone moiety. Previous studies showed that alantolactone inhibits the nuclear factor κB (NF-κB) signaling pathway by targeting the inhibitor of NF-κB (IκB) kinase. However, in the present study, we demonstrated that alantolactone selectively down-regulated the expression of tumor necrosis factor (TNF) receptor 1 (TNF-R1) in human lung adenocarcinoma A549 cells. Alantolactone did not affect the expression of three adaptor proteins recruited to TNF-R1. The down-regulation of TNF-R1 expression by alantolactone was suppressed by an inhibitor of TNF-α-converting enzyme. Alantolactone increased the soluble forms of TNF-R1 that were released into the culture medium as an ectodomain. The structure-activity relationship of eight eudesmane derivatives revealed that an α-methylene-γ-lactone moiety was needed to promote TNF-R1 ectodomain shedding. In addition, parthenolide and costunolide, two sesquiterpene lactones with an α-methylene-γ-lactone moiety, increased the amount of soluble TNF-R1. Therefore, the present results demonstrate that sesquiterpene lactones with an α-methylene-γ-lactone moiety can down-regulate the expression of TNF-R1 by promoting its ectodomain shedding in A549 cells.
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- 2024
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7. Alantolactone derivatives inhibit the tumor necrosis factor α-induced nuclear factor κB pathway by a different mechanism from alantolactone.
- Author
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Vu QV, Baba K, Sasaki S, Kawaguchi K, Hirano H, Osada H, and Kataoka T
- Subjects
- Humans, NF-kappa B metabolism, Tumor Necrosis Factor-alpha pharmacology, NF-KappaB Inhibitor alpha, Intercellular Adhesion Molecule-1 metabolism, Lactones pharmacology, Human Umbilical Vein Endothelial Cells, Sesquiterpenes, Eudesmane pharmacology, Lung Neoplasms metabolism
- Abstract
Alantolactone is a eudesmane-type sesquiterpene lactone that exerts various biological effects, including anti-inflammatory activity. In the present study, screening using the RIKEN Natural Products Depository chemical library identified alantolactone derivatives that inhibited the expression of intercellular adhesion molecule-1 (ICAM-1) on human umbilical vein endothelial cells stimulated with proinflammatory cytokines and Toll-like receptor ligands. In human lung adenocarcinoma A549 cells stimulated with tumor necrosis factor-α (TNF-α), six alantolactone derivatives inhibited ICAM-1 expression in a dose-dependent manner and at IC
50 values of 13-21 μM, whereas that of alantolactone was 5 μM. Alantolactone possesses an α-methylene-γ-lactone moiety, whereas alantolactone derivatives do not. In the nuclear factor κB (NF-κB) signaling pathway, alantolactone prevented the TNF-α-induced phosphorylation and degradation of the inhibitor of NF-κB α (IκBα) protein, and its downstream signaling pathway. In contrast, alantolactone derivatives neither reduced TNF-α-induced IκBα degradation nor the nuclear translocation of the NF-κB subunit RelA, but inhibited the binding of RelA to the ICAM-1 promoter. The inhibitory activities of alantolactone and alantolactone derivatives were attenuated by glutathione. These results indicate that alantolactone derivatives inhibit the TNF-α-induced NF-κB pathway by a different mechanism from alantolactone., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
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8. Synonymous Mutations Can Alter Protein Dimerization Through Localized Interface Misfolding Involving Self-entanglements.
- Author
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Lan PD, Nissley DA, Sitarik I, Vu QV, Jiang Y, To P, Xia Y, Fried SD, Li MS, and O'Brien EP
- Subjects
- Kinetics, Protein Folding, Escherichia coli enzymology, Exoribonucleases chemistry, Exoribonucleases genetics, Protein Multimerization genetics, Silent Mutation, Cell Membrane enzymology
- Abstract
Synonymous mutations in messenger RNAs (mRNAs) can reduce protein-protein binding substantially without changing the protein's amino acid sequence. Here, we use coarse-grain simulations of protein synthesis, post-translational dynamics, and dimerization to understand how synonymous mutations can influence the dimerization of two E. coli homodimers, oligoribonuclease and ribonuclease T. We synthesize each protein from its wildtype, fastest- and slowest-translating synonymous mRNAs in silico and calculate the ensemble-averaged interaction energy between the resulting dimers. We find synonymous mutations alter oligoribonuclease's dimer properties. Relative to wildtype, the dimer interaction energy becomes 4% and 10% stronger, respectively, when translated from its fastest- and slowest-translating mRNAs. Ribonuclease T dimerization, however, is insensitive to synonymous mutations. The structural and kinetic origin of these changes are misfolded states containing non-covalent lasso-entanglements, many of which structurally perturb the dimer interface, and whose probability of occurrence depends on translation speed. These entangled states are kinetic traps that persist for long time scales. Entanglements cause altered dimerization energies for oligoribonuclease, as there is a large association (odds ratio: 52) between the co-occurrence of non-native self-entanglements and weak-binding dimer conformations. Simulated at all-atom resolution, these entangled structures persist for long timescales, indicating the conclusions are independent of model resolution. Finally, we show that regions of the protein we predict to have changes in entanglement are also structurally perturbed during refolding, as detected by limited-proteolysis mass spectrometry. Thus, non-native changes in entanglement at dimer interfaces is a mechanism through which oligomer structure and stability can be altered., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
- Published
- 2024
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9. Outcomes of laparoscopic choledochotomy using cholangioscopy via percutaneous-choledochal tube for the treatment of hepatolithiasis and choledocholithiasis: A preliminary Vietnamese study.
- Author
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Le LV, Vu QV, Le TV, Le HT, Dang KK, Vu TN, Nguyen AHN, and Tran TM
- Abstract
Backgrounds/aims: Hepatolithiasis and choledocholithiasis are frequent pathologies and unfortunately, with the current treatment strategies, the recurrence incidence is still high. This study aimed to assess the outcomes of laparoscopic choledochotomy using cholangioscopy via the percutaneous-choledochal tube for the treatment of hepatolithiasis and choledocholithiasis in Vietnamese patients., Methods: A cross-sectional study of patients with hepatolithiasis and/or choledocholithiasis who underwent laparoscopic choledochotomy using intraoperative cholangioscopy via percutaneous-choledochal tube at the Department of Hepatopancreatobiliary Surgery, 108 Military Central Hospital, from June 2017 to March 2020., Results: A total of 84 patients were analyzed. Most patients were females (56.0%) with a median age of 55.56 years. Among them, 41.8% of patients had previous abdominal operations, with 33.4% having choledochotomy. All patients underwent successful laparoscopic common bile duct exploration followed by T-tube drainage without needing to convert to open surgery. Most patients (64.3%) had both intrahepatic and extrahepatic stones. The rate of stones ≥ 10 mm in diameter was 64.3%. Biliary strictures were observed in 19.1% of patients during cholangioscopy. Complete removal of stones was achieved in 54.8% of patients. Intraoperative complications were encountered in two patients, but there was no need to change the strategy. The mean operating time was 121.85 ± 30.47 minutes. The early postoperative complication rate was 9.6%, and all patients were managed conservatively. The residual stones were removed through the T-tube tract by subsequent choledochoscopy in 34/38 patients, so the total success rate was 95.2%., Conclusions: Laparoscopic choledochotomy combined with cholangioscopy through the percutaneous-choledochal tube is a safe and effective strategy for hepatolithiasis and/or choledocholithiasis, even in patients with a previous choledochotomy.
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- 2024
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10. Conductive Glassy Nonconjugated Open-Shell Radical Polymer with Organosulfur Backbone for Macroscopic Conductivity.
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Thi QV, Nguyen QH, Choi YS, Jeon SY, Boudouris BW, and Joo Y
- Abstract
Nonconjugated organic radicals with an open-shell radical active group exhibit unique functionality due to their radical pendant site. Compared with the previously studied doped conjugated polymers, radical polymers reveal superior processability, stability, and optical properties. Despite the success of organic radical polymer conductors based on the TEMPO radicals, it still requires potential design substitutions to meet the fundamental limits of charge transport in the radical polymer. To do so, we demonstrate that the amorphous, nonconjugated radical polymer with backbone-pendant group interaction and low glass transition temperature enables the macromolecules to have rapid charge transport in the solid state, resulting in conductivity higher than 32 S m
-1 . This charge transport is due to the formation of the local ordered regime with an energetically favored orientation caused by the strong coupling between the backbone and pendant group, which can significantly modulate the polymer packing with active electronic communications. The nonconjugate nature of the radical polymer maintains an optical transparency up to 98% at a 1.5 μm thick film. Thus, this effort will be a dramatically advanced model in the organic radical community for the creation of next-generation polymer conductors., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)- Published
- 2024
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11. A comparative patient-level prediction study in OMOP CDM: applicative potential and insights from synthetic data.
- Author
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Ahmadi N, Nguyen QV, Sedlmayr M, and Wolfien M
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- Humans, Databases, Factual, Electronic Health Records, Machine Learning, Medical Informatics
- Abstract
The emergence of collaborations, which standardize and combine multiple clinical databases across different regions, provide a wealthy source of data, which is fundamental for clinical prediction models, such as patient-level predictions. With the aid of such large data pools, researchers are able to develop clinical prediction models for improved disease classification, risk assessment, and beyond. To fully utilize this potential, Machine Learning (ML) methods are commonly required to process these large amounts of data on disease-specific patient cohorts. As a consequence, the Observational Health Data Sciences and Informatics (OHDSI) collaborative develops a framework to facilitate the application of ML models for these standardized patient datasets by using the Observational Medical Outcomes Partnership (OMOP) common data model (CDM). In this study, we compare the feasibility of current web-based OHDSI approaches, namely ATLAS and "Patient-level Prediction" (PLP), against a native solution (R based) to conduct such ML-based patient-level prediction analyses in OMOP. This will enable potential users to select the most suitable approach for their investigation. Each of the applied ML solutions was individually utilized to solve the same patient-level prediction task. Both approaches went through an exemplary benchmarking analysis to assess the weaknesses and strengths of the PLP R-Package. In this work, the performance of this package was subsequently compared versus the commonly used native R-package called Machine Learning in R 3 (mlr3), and its sub-packages. The approaches were evaluated on performance, execution time, and ease of model implementation. The results show that the PLP package has shorter execution times, which indicates great scalability, as well as intuitive code implementation, and numerous possibilities for visualization. However, limitations in comparison to native packages were depicted in the implementation of specific ML classifiers (e.g., Lasso), which may result in a decreased performance for real-world prediction problems. The findings here contribute to the overall effort of developing ML-based prediction models on a clinical scale and provide a snapshot for future studies that explicitly aim to develop patient-level prediction models in OMOP CDM., (© 2024. The Author(s).)
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- 2024
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12. Adult-to-adult right lobe graft living donor liver transplantation for acute-on-chronic liver failure: a single-centre retrospective study in Vietnam.
- Author
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Vu QV, Le TV, Le HT, Nguyen AHN, and Nguyen DT
- Abstract
Introduction: Acute-on-chronic liver failure (ACLF) has a high mortality rate, and liver transplantation is considered a definite treatment for patients with this condition. This study aims to evaluate the outcomes of living donor liver transplantation (LDLT) in ACLF patients in a single centre in a lower middle-income country, Vietnam., Materials and Methods: This was a retrospective study at the 108 Military Central Hospital (Hanoi, Vietnam), enroling 51 patients diagnosed with ACLF based on Asian Pacific Association for the Study of the Liver (APASL) criteria who underwent LDLT with a right lobe graft from December 2019 to December 2022. The authors utilize the model for end-stage liver disease (MELD) and APASL ACLF Research Consortium (AARC) scores to evaluate and stratify the severity of ACLF., Results: The average age of all patients was 47.27±13.61, with 88.24% being male. The average BMI was 22.78±2.61. The most common underlying liver disease was chronic viral hepatitis B (88.2%). The average MELD score of the patients was 34.90±5.61, with 33.3% having MELD score greater than or equal to 40. In terms of ACLF severity, five patients (9.8%) had grade I ACLF, 35 patients (68.6%) had grade II ACLF, and 11 patients (21.6%) had grade III ACLF. The average AARC score was 9.43±1.68. The duration of treatment in the ICU was 8.59±7.27 days, and the length of hospital stay was 28.02±13.45 days. The most common post-transplant complication was biliary complication (19.61%). Death occurred in 7 patients (13.7%). The survival rates at 6 months, 1 year, and 3 years were 84%, 81.7%, and 81.7%, respectively., Conclusion: Living donor liver transplantation for ACLF patients is safe and has a high post-transplant survival rate. Multidisciplinary care before, during, and after surgery, and the decision to do a liver transplant early, is essential in saving the lives of ACLF patients., Competing Interests: None.Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)
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- 2024
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13. A Model for Gastric Cancer Risk Prediction Based on MUC1 Polymorphisms and Health-risk Behaviors in a Vietnamese Population.
- Author
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Nguyen NT, Dang NDT, Vu QV, Dang AK, and Ta TV
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- Humans, Male, Female, Genetic Predisposition to Disease, Mucin-1 genetics, Case-Control Studies, Southeast Asian People, Genome-Wide Association Study, Polymorphism, Single Nucleotide, Risk-Taking, Risk Factors, Stomach Neoplasms epidemiology, Stomach Neoplasms genetics, Stomach Neoplasms pathology
- Abstract
Background/aim: Although the expression of mucin 1(MUC1) and prostate stem cell antigen (PSCA) genes is correlated with gastric cancer development and progression, the utility of these two genes as biomarkers of gastric cancer prognosis still needs to be confirmed in clinical practice. This study aimed to develop a model predictive of gastric cancer that integrates several significant single nucleotide polymorphisms (SNPs) of MUC1 and PSCA genes, and some health-risk behavior factors in a Vietnamese population., Patients and Methods: A total of 302 patients with primary gastric carcinoma and 304 healthy persons were included in a case-control study. The generalized linear model was used with the profile of age, sex, history of smoking and using alcohol, personal and family medical history of stomach diseases, and the SNPs of MUC1 and PSCA. The prognostic value of the model was assessed by the area under a receiver operating characteristic curve (AUC) and Akaike Information Criterion (AIC) values., Results: In male participants, the final model, consisting of age, sex, history of smoking and using alcohol, personal and family medical history of stomach diseases and SNP MUC1 rs4072037, provided acceptable discrimination, with an AUC of 0.6374 and the lowest AIC value (539.53). In female participants, the predictive model including age, sex, history of smoking and using alcohol, personal and family medical history of stomach diseases, SNPs MUC1 rs4072037 and rs2070803 had an AUC of 0.6937 and AIC of 266.80. The calibration plots of the male model approximately fitted the ideal calibration line., Conclusion: The predictive model based on age, sex, medical history, and genetic and health-risk behavior factors has a high potential in determining gastric cancer. Further studies that elucidate other genetic variants should be carried out to define high-risk gastric cancer groups and propose appropriate personalized prevention., (Copyright © 2023, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)
- Published
- 2023
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14. Phenotype and genotype features of Vietnamese children with pachyonychia congenita.
- Author
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Chu HT, Dinh Duong TA, Le DH, Le TV, Nguyen BB, Dang CV, and Vu QV
- Subjects
- Humans, Child, Keratin-6 genetics, Southeast Asian People, Vietnam, Genotype, Phenotype, Mutation, Keratins genetics, Leukoplakia, Oral complications, Pachyonychia Congenita genetics, Pachyonychia Congenita complications, Pachyonychia Congenita diagnosis, Exanthema
- Abstract
Background: Pachyonychia congenita (PC) is a group of autosomal dominant disorders caused by mutations in one of five keratin genes (KRT6A, KRT6B, KRT6C, KRT16, or KRT17). PC is an extremely rare condition. To our knowledge, this is the largest genotype-phenotype study of PC in a Vietnamese population to date., Materials and Methods: We investigated keratin gene mutations and clinical features of seven Vietnamese children with PC., Results: The seven Vietnamese patients were from six different families (two patients in the same family) from across Northern, Central, and Southern Vietnam. All children displayed PC symptoms before 1 year of age, but diagnosis was delayed in 4/7 patients. Thick fingernails, thick toenails, oral leukokeratosis, and follicular hyperkeratosis were the most common features recorded by all seven patients. Plantar keratoderma and thick fingernails were the clinical features associated with the most significant effect on daily function. All patients had mutations in KRT6A (PC-K6a) focused on the 1A and 2B domains. We found three distinct types of mutations (K6a R466P, K6a N171K, and K6a N172del). One mutation (N172del) was common to 5/7 (71.4%) of the patients., Conclusions: Individuals displaying nail dystrophy, oral leukokeratosis, follicular hyperkeratosis, and plantar keratoderma should be referred for genetic testing given the high likelihood of a PC-K6a-related mutation in patients with this constellation of clinical signs., (Copyright © 2023 Taiwan Pediatric Association. Published by Elsevier B.V. All rights reserved.)
- Published
- 2023
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15. How soluble misfolded proteins bypass chaperones at the molecular level.
- Author
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Halder R, Nissley DA, Sitarik I, Jiang Y, Rao Y, Vu QV, Li MS, Pritchard J, and O'Brien EP
- Subjects
- Molecular Chaperones metabolism, Protein Folding
- Abstract
Subpopulations of soluble, misfolded proteins can bypass chaperones within cells. The extent of this phenomenon and how it happens at the molecular level are unknown. Through a meta-analysis of the experimental literature we find that in all quantitative protein refolding studies there is always a subpopulation of soluble but misfolded protein that does not fold in the presence of one or more chaperones, and can take days or longer to do so. Thus, some misfolded subpopulations commonly bypass chaperones. Using multi-scale simulation models we observe that the misfolded structures that bypass various chaperones can do so because their structures are highly native like, leading to a situation where chaperones do not distinguish between the folded and near-native-misfolded states. More broadly, these results provide a mechanism by which long-time scale changes in protein structure and function can persist in cells because some misfolded states can bypass components of the proteostasis machinery., (© 2023. The Author(s).)
- Published
- 2023
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16. Is Posttranslational Folding More Efficient Than Refolding from a Denatured State: A Computational Study.
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Vu QV, Nissley DA, Jiang Y, O'Brien EP, and Li MS
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- Ribosomes metabolism, Proteins metabolism, Molecular Dynamics Simulation, Protein Biosynthesis, Protein Folding
- Abstract
The folding of proteins into their native conformation is a complex process that has been extensively studied over the past half-century. The ribosome, the molecular machine responsible for protein synthesis, is known to interact with nascent proteins, adding further complexity to the protein folding landscape. Consequently, it is unclear whether the folding pathways of proteins are conserved on and off the ribosome. The main question remains: to what extent does the ribosome help proteins fold? To address this question, we used coarse-grained molecular dynamics simulations to compare the mechanisms by which the proteins dihydrofolate reductase, type III chloramphenicol acetyltransferase, and d-alanine-d-alanine ligase B fold during and after vectorial synthesis on the ribosome to folding from the full-length unfolded state in bulk solution. Our results reveal that the influence of the ribosome on protein folding mechanisms varies depending on the size and complexity of the protein. Specifically, for a small protein with a simple fold, the ribosome facilitates efficient folding by helping the nascent protein avoid misfolded conformations. However, for larger and more complex proteins, the ribosome does not promote folding and may contribute to the formation of intermediate misfolded states cotranslationally. These misfolded states persist posttranslationally and do not convert to the native state during the 6 μs runtime of our coarse-grain simulations. Overall, our study highlights the complex interplay between the ribosome and protein folding and provides insight into the mechanisms of protein folding on and off the ribosome.
- Published
- 2023
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17. Reversion of glucocorticoid-induced senescence and collagen synthesis decrease by LY294002 is mediated through p38 in skin.
- Author
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Le QV, Wen SY, Chen CJ, Huang CY, and Kuo WW
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- Mice, Humans, Animals, Mice, Inbred C57BL, Receptors, Glucocorticoid, Phosphoinositide-3 Kinase Inhibitors, Atrophy, Glucocorticoids, Phosphatidylinositol 3-Kinases
- Abstract
Glucocorticoids (GCs) are the most common treatment for inflammatory skin disorders; however, they show several adverse side effects, including atrophy and collagen decrease following chronic treatment. In particular, transcription factors and p38 signaling for collagen synthesis have been shown to be suppressed by the active glucocorticoid receptor (GR). LY294002 (LY), a phosphoinositide 3-kinase (PI3K) inhibitor, has been reported to protect keratinocytes in epidermis against GC-induced hypoplasia; however, its protective effect in dermis remains unclear. Furthermore, clobetasol propionate (CP) is the most used commercial synthetic GC, yet studies on how CP causes side effects in dermal fibroblasts are limited. In this study, dermal atrophy was modeled using CP in human dermal fibroblasts (HDFs) and C57BL/6 mice. CP treatment significantly upregulated FK506 binding protein 5 (FKBP51), an atrophy marker (2.4 ± 0.25 and 3.3 ± 0.3 fold in in vitro and in vivo , respectively), phosphorylated GR (1.96 ± 0.08 and 2.29 ± 0.25 fold in in vitro and in vivo , respectively), decreased fibroblast proliferation (82.71 ± 1.95% in in vitro ), reduced collagen synthesis (0.36 ± 0.05 and 0.3 ± 0.1 fold in in vitro and in vivo , respectively), and induced aging, all of which were reversed by LY treatment (from 1.43 ± 0.08 to 2.8 ± 0.12 fold) without showing growth inhibition and exerting the anti-inflammation of CP. Interestingly, the protective effect of LY was dose-dependently reversed by treatment with a p38 inhibitor and reached 2.9 ± 0.15 fold at dose 20 µM. Taken together, our results demonstrate that LY reduced CP-induced upregulation of the atrophy marker FKBP51, GR phosphorylation, and GR nuclear translocation via the activation of p38, whilst maintaining the anti-inflammatory effect of glucocorticoids., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)
- Published
- 2022
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18. Ion-Incorporative, Degradable Nanocellulose Crystal Substrate for Sustainable Carbon-Based Electronics.
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Thi QV, Ko J, Jo Y, and Joo Y
- Abstract
Electronic wastes from transient electronics accumulate biologically harmful materials with global concern. Recycling these wastes could prevent the deposition of hazardous chemicals and toxic materials to the environment while saving scarce natural compounds and valuable resources. Here, we report a sustainable electronic device, taking advantage of carbon resources and a biodegradable cellulose composite. The device consists of an ambient-stable carbon nanotube as a semiconductor, graphene as electrodes, and a free-standing cellulose filter paper/nanocellulose composite as a dielectric layer. The dual-functional cellulose composite acting simultaneously as a robust substrate and a dielectric is demonstrated, which is compatible with solution device fabrication processes. An optimized channel dimension of 5 mm × 3 mm with the addition of ions that facilitates a charge transport realized a device with an on-current per width of 9.6 μA mm
-1 , an on/off ratio >102 , a field-effect mobility of 2.03 cm2 V-1 s-1 , and long-term stability over 30 days under ambient conditions. Successful separation of the carbonaceous components via an eco-friendly solution sorting protocol allowed the recycled device to display excellent electronic performance, with a recapture efficiency of 90%. This effort demonstrates a processable, low-cost, and sustainable electronic system that can be applied in the current realm of the semiconducting and sensing industry.- Published
- 2022
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19. Clinical Epidemiology Characteristics and Etiology of Febrile Neutropenia in Children: Analysis of 421 Cases.
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Nguyen SN, Vu LT, Vu QV, Tran TT, and Dinh VTT
- Abstract
The congenital immune system includes neutrophils, which perform a variety of functions. Congenital and acquired neutropenia are rare illnesses with an underestimated prevalence in children. The aim of this study is to examine the epidemiology and etiology of febrile neutropenia in children at Haiphong Children's Hospital, Haiphong, Vietnam. Methods: A cross-sectional study was carried out on 421 febrile neutropenia children. Clinical and laboratory characteristics were examined. Results: The median age (IQR) was 25.0 (12.5-59.5) months. The male-to-female ratio was 1.35/1. There were twice as many children living in the suburbs (66.98%) as in urban areas (33.02%). The mean (SD) temperature at admission was 38.50 ± 0.59 °C. Diagnosed causes associated with neutropenia included acute respiratory infections 250 (59.45%), gastrointestinal infections 68 (16.1%), erythema 37 (8.79%), acute leukemia 15 (3.56%), urinary tract infection 5 (1.19%), and encephalitis/meningitis 4 (0.95%). Viral etiology accounted for 61.52% (259): influenza type A -50.19% (130), influenza type B -31.27% (81), dengue virus -14.67% (38), measles virus 1-93% (5), rotavirus-1.54% (4), and EBV -0.4% (1). Twenty-five patients (5.94%) were found to have bacteria in their cultures, with Streptococcus pneumonia being the most common (eight patients; 32%). Conclusions: Febrile neutropenia was common in children under 2 years old. Primary clinical manifestations were acute upper respiratory tract infections, and viruses most commonly caused febrile neutropenia. Further studies with larger sample sizes are needed to determine the cause of febrile neutropenia.
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- 2022
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20. Correction to "Ribosome Elongation Kinetics of Consecutively Charged Residues Are Coupled to Electrostatic Force".
- Author
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Leininger SE, Rodriguez J, Vu QV, Jiang Y, Li MS, Deutsch C, and O'Brien EP
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- 2022
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21. Ribosome Elongation Kinetics of Consecutively Charged Residues Are Coupled to Electrostatic Force.
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Leininger SE, Rodriguez J, Vu QV, Jiang Y, Li MS, Deutsch C, and O'Brien EP
- Subjects
- Amino Acids metabolism, Kinetics, Models, Chemical, Models, Theoretical, Protein Conformation, Ribosomes metabolism, Ribosomes ultrastructure, Static Electricity, Protein Biosynthesis genetics, Protein Biosynthesis physiology, Ribosomes physiology
- Abstract
The speed of protein synthesis can dramatically change when consecutively charged residues are incorporated into an elongating nascent protein by the ribosome. The molecular origins of this class of allosteric coupling remain unknown. We demonstrate, using multiscale simulations, that positively charged residues generate large forces that move the P-site amino acid away from the A-site amino acid. Negatively charged residues generate forces of similar magnitude but move the A- and P-sites closer together. These conformational changes, respectively, increase and decrease the transition state barrier height to peptide bond formation, explaining how charged residues mechanochemically alter translation speed. This mechanochemical mechanism is consistent with in vivo ribosome profiling data exhibiting proportionality between translation speed and the number of charged residues, experimental data characterizing nascent chain conformations, and a previously published cryo-EM structure of a ribosome-nascent chain complex containing consecutive lysines. These results expand the role of mechanochemistry in translation and provide a framework for interpreting experimental results on translation speed.
- Published
- 2021
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22. The driving force for co-translational protein folding is weaker in the ribosome vestibule due to greater water ordering.
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Vu QV, Jiang Y, Li MS, and O'Brien EP
- Abstract
Interactions between the ribosome and nascent chain can destabilize folded domains in the ribosome exit tunnel's vestibule, the last 3 nm of the exit tunnel where tertiary folding can occur. Here, we test if a contribution to this destabilization is a weakening of hydrophobic association, the driving force for protein folding. Using all-atom molecular dynamics simulations, we calculate the potential-of-mean force between two methane molecules along the center line of the ribosome exit tunnel and in bulk solution. Associated methanes, we find, are half as stable in the ribosome's vestibule as compared to bulk solution, demonstrating that the hydrophobic effect is weakened by the presence of the ribosome. This decreased stability arises from a decrease in the amount of water entropy gained upon the association of the methanes. And this decreased entropy gain originates from water molecules being more ordered in the vestibule as compared to bulk solution. Therefore, the hydrophobic effect is weaker in the vestibule because waters released from the first solvation shell of methanes upon association do not gain as much entropy in the vestibule as they do upon release in bulk solution. These findings mean that nascent proteins pass through a ribosome vestibule environment that can destabilize folded structures, which has the potential to influence co-translational protein folding pathways, energetics, and kinetics., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)
- Published
- 2021
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23. Seven traditional Chinese herbal extracts fermented by Lactobacillus rhamnosus provide anti-pigmentation effects by regulating the CREB/MITF/tyrosinase pathway.
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Ho CC, Ng SC, Chuang HL, Chen JY, Wen SY, Kuo CH, Mahalakshmi B, Le QV, Huang CY, and Kuo WW
- Subjects
- Animals, Cell Line, Tumor, Cell Survival drug effects, Cell Survival radiation effects, Drugs, Chinese Herbal metabolism, Fermentation, Humans, Melanins biosynthesis, Mice, Mice, Inbred C57BL, Mice, Nude, Microphthalmia-Associated Transcription Factor metabolism, Signal Transduction, Skin drug effects, Skin metabolism, Skin pathology, Skin radiation effects, Skin Pigmentation radiation effects, alpha-MSH antagonists & inhibitors, Drugs, Chinese Herbal pharmacology, Lacticaseibacillus rhamnosus metabolism, Monophenol Monooxygenase metabolism, Skin Pigmentation drug effects, Ultraviolet Rays
- Abstract
Skin pigmentation is resulted from several processes, such as melanin synthesis transportation and abnormal melanin accumulation in keratinocytes. Various studies have suggested that seven traditional Chinese herbal extracts from Atractylodes macrocephala, Paeonia lactiflora, Bletilla striata, Poria cocos, Dictamnus dasycarpus, Ampelopsis japonica and Tribulus terrestris (which we collectively named ChiBai), show several protective effects toward skin-related diseases. Lactobacillus rhamnosus, a lactic acid bacterium, has been reported to treat skin inflammation and atopic dermatitis. In this study, the broth produced by the cofermentation of ChiBai with Lactobacillus rhamnosus was studied for its effects on skin pigmentation through in vitro and in vitro experiments. In the in vitro experiments, we found that the fermented broth of ChiBai (FB-ChiBai) suppressed alpha-melanocyte stimulating hormone (α-MSH)-induced melanogenesis in B16F0 murine melanoma cells without any cytotoxicity at a concentration of 0.5%. FB-ChiBai significantly attenuated melanin production, tyrosinase activities and melanogenesis-related signaling pathways. Treatment with FB-ChiBai also reduced the nuclear translocation and promoter binding activities of MITF. In the in vivo experiments, FB-ChiBai was topically applied to the dorsal skin of C57BL/6J nude mice and concurrently irradiated with UVB, three times a week for 8 weeks. The results indicated that FB-ChiBai alleviated UVB-induced hyperpigmentation by reducing epidermal hyperplasia and inhibiting the CREB/MITF/tyrosinase pathway. In conclusion, our data indicated that the anti-melanogenic effects of FB-ChiBai are mediated by the inhibition of CREB/MITF/tyrosinase signaling pathway. The findings suggest that FB-ChiBai can protect against UV-B irradiation and that it might be used as an agent in cosmetic products to protect against UVB-induced hyperpigmentation., (© 2020 Wiley Periodicals LLC.)
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- 2021
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24. Molecular dynamics performance for coronavirus simulation by C, N, O, and S atoms implementation dreiding force field: drug delivery atomic interaction in contact with metallic Fe, Al, and steel.
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Karimipour A, Amini A, Nouri M, D'Orazio A, Sabetvand R, Hekmatifar M, Marjani A, and Bach QV
- Abstract
Coronavirus causes some illnesses to include cold, COVID-19, MERS, and SARS. This virus can be transmitted through contact with different atomic matrix between humans. So, this atomic is essential in medical cases. In this work, we describe the atomic manner of this virus in contact with various metallic matrix such as Fe, Al, and steel with equilibrium molecular dynamic method. For this purpose, we reported physical properties such as temperature, total energy, distance and angle of structures, mutual energy, and volume variation of coronavirus. In this approach, coronavirus is precisely simulated by O, C, S, and N atoms and they are implemented dreiding force field. Our simulation shows that virus interaction with steel matrix causes the maximum removing of the virus from the surfaces. After 1 ns, the atomic distance between these two structures increases from 45 to 75 Å. Furthermore, the volume of coronavirus 14.62% increases after interaction with steel matrix. This atomic manner shows that coronavirus removes and destroyed with steel surface, and this metallic structure can be a promising material for use in medical applications., Competing Interests: Conflict of interestThere is no conflict of interest., (© OWZ 2020.)
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- 2021
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25. Thermal and hydrodynamic properties of coronavirus at various temperature and pressure via molecular dynamics approach.
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Malekahmadi O, Zarei A, Botlani Esfahani MB, Hekmatifar M, Sabetvand R, Marjani A, and Bach QV
- Abstract
COVID-19 is an epidemic virus arising from a freshly discovered coronavirus. Most people involved with the coronavirus will experience slight to moderate respiratory disease and recover without needing particular therapy. In this work, the atomic stability of the coronavirus at different thermodynamic properties such as temperature and pressure, was studied. For this purpose, the manner of this virus by atomic precession was described with a molecular dynamics approach. For the atomic stability of coronavirus description, physical properties such as temperature, total energy, volume variation, and atomic force of this structure were reported. In molecular dynamics approach, coronavirus is precisely simulated via S, O, N, and C atoms and performed Dreiding force field to describe these atoms interaction in the virus. Simulation results show that coronavirus stability has reciprocal relation with atomic temperature and pressure. Numerically, after 2.5 ns simulation, the potential energy varies from - 31,163 to - 26,041 eV by temperature changes from 300 to 400 K. Furthermore, this physical parameter decreases to - 28,045 eV rate at 300 K and 2 bar pressure. The volume of coronavirus is another crucial parameter to the stability description of this structure. The simulation shows that coronavirus volume 92% and 14% increases by 100 K and 2 bar variation of simulation temperature and pressure, respectively., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Akadémiai Kiadó, Budapest, Hungary 2020.)
- Published
- 2021
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26. Implementation of data intelligence models coupled with ensemble machine learning for prediction of water quality index.
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Abba SI, Pham QB, Saini G, Linh NTT, Ahmed AN, Mohajane M, Khaledian M, Abdulkadir RA, and Bach QV
- Subjects
- India, Intelligence, Machine Learning, Rivers, Fuzzy Logic, Water Quality
- Abstract
In recent decades, various conventional techniques have been formulated around the world to evaluate the overall water quality (WQ) at particular locations. In the present study, back propagation neural network (BPNN) and adaptive neuro-fuzzy inference system (ANFIS), support vector regression (SVR), and one multilinear regression (MLR) are considered for the prediction of water quality index (WQI) at three stations, namely Nizamuddin, Palla, and Udi (Chambal), across the Yamuna River, India. The nonlinear ensemble technique was proposed using the neural network ensemble (NNE) approach to improve the performance accuracy of the single models. The observed WQ parameters were provided by the Central Pollution Control Board (CPCB) including dissolved oxygen (DO), pH, biological oxygen demand (BOD), ammonia (NH
3 ), temperature (T), and WQI. The performance of the models was evaluated by various statistical indices. The obtained results indicated the feasibility of the developed data intelligence models for predicting the WQI at the three stations with the superior modelling results of the NNE. The results also showed that the minimum values for root mean square (RMS) varied between 0.1213 and 0.4107, 0.003 and 0.0367, and 0.002 and 0.0272 for Nizamuddin, Palla, and Udi (Chambal), respectively. ANFIS-M3, BPNN-M4, and BPNN-M3 improved the performance with regard to an absolute error by 41%, 4%, and 3%, over other models for Nizamuddin, Palla, and Udi (Chambal) stations, respectively. The predictive comparison demonstrated that NNE proved to be effective and can therefore serve as a reliable prediction approach. The inferences of this paper would be of interest to policymakers in terms of WQ for establishing sustainable management strategies of water resources.- Published
- 2020
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27. Insight into conditioning landfill sludge with ferric chloride and a Fenton reagent: Effects on the consolidation properties and advanced dewatering.
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Zhang X, Lu Y, Yao J, Wu Y, Tran QC, and Vu QV
- Subjects
- Filtration, Hydrogen Peroxide chemistry, Iron chemistry, Oxidation-Reduction, Sewage chemistry, Waste Disposal Facilities, Water chemistry, Chlorides chemistry, Ferric Compounds chemistry, Waste Disposal, Fluid methods, Water Pollutants, Chemical chemistry
- Abstract
The landfill sludge in storage reservoirs needs to be dewatered and disposed of for environmental and engineering purposes. The key factors are the high organic matter content and low permeability. Chemical conditioning is considered an efficient method for adjusting the properties of sludge. In this paper, two typical chemical agents, FeCl
3 and a Fenton reagent with different additive amounts, are studied and compared for dewatering and consolidation purposes. Compression experiments and consolidation experiments are compared, and the coefficient of compressibility and compression index are obtained and compared. Then, the sludge permeability, grain size distribution variations, specific resistance to filtration (SRF) and morphology observations are considered to analyse the treatment mechanism. The results indicate that the properties of landfill sludge will change as the curing time increases. FeCl3 and Fenton are both effective in improving the consolidation and permeability properties of sludge. For the conditioning process, the optimum FeCl3 content is 20%, and the process is dominated by coagulation if FeCl3 is less than 20%; otherwise, it is dominated by hydrolysis. For the Fenton reagent, the optimum Fe2+ content and H2 O2 content are 4% and 12%, respectively. The depolymerization effect of the Fenton reagent leads to the oxidation and recombination of the polar group on extracellular polymeric substances (EPSs). The results can be used to explain the conditioning mechanism of the effective agents of FeCl3 and Fenton and compare the corresponding consolidation properties. The consolidation characteristics provide a reference for further application of vacuum preloading in the sludge disposal process., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)- Published
- 2020
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28. Assessment and source quantification of heavy metal(loid)s in surface water using multivariate analyses from the Saigon River, Vietnam.
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Nguyen BT, Nguyen VN, Truong HTT, Do DD, Nguyen TX, Nguyen DTP, Nguyen MH, Dong HP, Le AH, and Bach QV
- Subjects
- Cities, Environmental Monitoring, Multivariate Analysis, Rivers, Seasons, Vietnam, Water, Metals, Heavy analysis, Water Pollutants, Chemical analysis
- Abstract
The metal concentration in surface water of a river could be affected by season, position, and oceanic process such as tide. The current study aimed to (1) examine the heavy metal(loid) concentration in surface water from the Saigon River as affected by the combination of season, tide, and position and (2) apportion and quantify pollution sources. Ninety-six surface water samples were collected from 13 sites on the River in four campaigns (rainy season + ebb tide, rainy season + flood tide, dry season + ebb tide, and dry season + flood tide). Eight heavy metal(loid)s (Al, B, Bi, Fe, Mn, Pb, Sr, and Zn) were measured and subjected to multivariate analyses. Three-way ANOVA showed that in the rainy season, the total concentration of the metal(loid)s (TCM) in two tides was not clearly different from each other while in the dry season the TCM was significantly higher during the ebb tide than during the flood tide. Principal component analysis/factor analysis and Pearson correlation matrix showed that the TCM could be derived from three main sources, grouped into anthropogenic activities such as industrial, agricultural, and domestic wastes from inside Ho Chi Minh city, and natural origins from lowland area and acid sulfate soil. Three pollution sources explained 70% and 68% of the total variance of TCM in the rainy and dry seasons, respectively. In brief, the metal(loid) concentration was significantly affected by the season and tide and the pollution sources could be derived from inside Ho Chi Minh City and from lowland areas beyond the river estuary.
- Published
- 2020
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29. Assessment of groundwater quality based on principal component analysis and pollution source-based examination: a case study in Ho Chi Minh City, Vietnam.
- Author
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Nguyen BT, Nguyen TMT, and Bach QV
- Subjects
- Cities, Escherichia coli physiology, Vietnam, Environmental Monitoring, Groundwater microbiology, Groundwater standards, Principal Component Analysis, Water Pollutants, Chemical analysis
- Abstract
The current study aimed to assess the quality of apportion pollution sources and examine the impacts of anthropogenic activities on groundwater. The study was implemented in two sequential steps of (1) bulk examination of groundwater quality followed by principal component analysis/factor analysis (PCA/FA) to apportion pollution sources and (2) pollution source-based examination to assess the effects of anthropogenic activities. Well-water samples were taken in Ho Chi Minh City, Vietnam, in 2015 (233 samples) and 2019 (20 samples) and analyzed for 8 and 15 water quality parameters, respectively. The results showed that 99% of studied wells had pH value lower than the permissible limit, and 29, 20, 15, and 14% of studied wells had concentrations of Fe, NH
4 + , COD (chemical oxygen demand), and coliform, respectively, higher than the maximum permissible limit. PCA/FA revealed that three pollution sources, ranked in the order of importance: agricultural, urban, and industrial activities, could mainly contribute to enriching the pollutant concentrations of groundwater. While agricultural activities may contaminate groundwater with organic substances, the urban area may enrich bacterial-pathogen density such as E. coli and coliform, and the industrial area may contribute to contaminating groundwater with some inorganic parameters. Groundwater quality index and ANOVA showed that groundwater of the studied area was poor to very poor in quality and that in the agricultural area was the worst of the three land-use types. In brief, the groundwater quality in the studied area was degraded and agricultural activities were the most important factor causing the degradation followed by urban and industrial activities.- Published
- 2020
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30. Combined biochar vertical flow and free-water surface constructed wetland system for dormitory sewage treatment and reuse.
- Author
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Nguyen XC, Tran TCP, Hoang VH, Nguyen TP, Chang SW, Nguyen DD, Guo W, Kumar A, La DD, and Bach QV
- Subjects
- Biological Oxygen Demand Analysis, Charcoal, Nitrogen, Vietnam, Waste Disposal, Fluid, Water, Sewage, Wetlands
- Abstract
A two-stage treatment system that included vertical flow (VF) and free-water surface (FWS) constructed wetlands was investigated for the dual purposes of sewage treatment and reuse. The VF included four layers (biochar, sand, gravel, and sandy soil), and the FWS was installed after the VF and used as a polishing tank. Two types of local plants, namely Colocasia esculenta and Canna indica, were planted in the VF and FWS, respectively. The system operated for approximately six months, and the experimental period was categorized into four stages that corresponded to changes in the hydraulic loading rate (HLR) (0.02-0.12 m/d). The removal efficiencies for total suspended solids (TSS), chemical oxygen demand (COD), biological oxygen demand (BOD
5 ), ammonia (NH4 -N), and total coliform (Tcol) were 71 ± 11%, 73 ± 13%, 79 ± 11%, 91 ± 3%, and 70 ± 20%, respectively. At HLRs of 0.04-0.06 m/d, the COD and BOD5 levels satisfied Vietnam's irrigation standards, with removable rates of 64% and 88%, respectively, and the TSS and Tcol levels satisfied Vietnam's standards for potable water. Furthermore, the NO3 -N levels satisfied the reuse limits, whereas the NH4 -N levels exceeded the reuse standards. At high HLRs (e.g., 0.12 m/d), all the effluent parameters, except Tcol and NO3 -N, exceeded the standards., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)- Published
- 2020
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31. Electrostatic Interactions Govern Extreme Nascent Protein Ejection Times from Ribosomes and Can Delay Ribosome Recycling.
- Author
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Nissley DA, Vu QV, Trovato F, Ahmed N, Jiang Y, Li MS, and O'Brien EP
- Subjects
- Models, Molecular, Protein Biosynthesis, Static Electricity, Escherichia coli metabolism, Escherichia coli Proteins metabolism, Ribosomes metabolism
- Abstract
The ejection of nascent proteins out of the ribosome exit tunnel, after their covalent bond to transfer-RNA has been broken, has not been experimentally studied due to challenges in sample preparation. Here, we investigate this process using a combination of multiscale modeling, ribosome profiling, and gene ontology analyses. Simulating the ejection of a representative set of 122 E. coli proteins we find a greater than 1000-fold variation in ejection times. Nascent proteins enriched in negatively charged residues near their C-terminus eject the fastest, while nascent chains enriched in positively charged residues tend to eject much more slowly. More work is required to pull slowly ejecting proteins out of the exit tunnel than quickly ejecting proteins, according to all-atom simulations. An energetic decomposition reveals, for slowly ejecting proteins, that this is due to the strong attractive electrostatic interactions between the nascent chain and the negatively charged ribosomal-RNA lining the exit tunnel, and for quickly ejecting proteins, it is due to their repulsive electrostatic interactions with the exit tunnel. Ribosome profiling data from E. coli reveals that the presence of slowly ejecting sequences correlates with ribosomes spending more time at stop codons, indicating that the ejection process might delay ribosome recycling. Proteins that have the highest positive charge density at their C-terminus are overwhelmingly ribosomal proteins, suggesting the possibility that this sequence feature may aid in the cotranslational assembly of ribosomes by delaying the release of nascent ribosomal proteins into the cytosol. Thus, nascent chain ejection times from the ribosome can vary greatly between proteins due to differential electrostatic interactions, can influence ribosome recycling, and could be particularly relevant to the synthesis and cotranslational behavior of some proteins.
- Published
- 2020
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32. Seasonal, spatial variation, and pollution sources of heavy metals in the sediment of the Saigon River, Vietnam.
- Author
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Nguyen BT, Do DD, Nguyen TX, Nguyen VN, Phuc Nguyen DT, Nguyen MH, Thi Truong HT, Dong HP, Le AH, and Bach QV
- Subjects
- Cities, Environmental Pollution analysis, Geologic Sediments chemistry, Rivers chemistry, Seasons, Vietnam, Environmental Monitoring, Metals, Heavy analysis, Water Pollutants, Chemical analysis
- Abstract
The current study was conducted to (1) examine seasonal and spatial distribution of heavy metals and metalloid in sediment from the Saigon River and (2) apportion and quantify their pollution sources. Ninety-six sediment samples were taken in the rainy and dry season on 13 sampling sites, distributed over the lower reaches of the River, to analyze for exchangeable concentration of 11 heavy metals and metalloid (Al, B, Cd, Co, Fe, In, Mn, Ni, Pb, Sr, and Zn), pH, EC, organic carbon content, and particle-size distribution. Generally, the concentration of 11 elements was ranked in the order Mn > Al > Fe > Zn > Sr > In > B > Ni > Co > Pb > Cd. Hierarchical cluster analysis grouped 13 sampling sites into two parts based on the similar concentration of the 11 elements. Three-way analysis of variance showed that the total exchangeable concentration of 11 elements was significantly higher in the rainy season than in the dry season and in the upper part than in the lower part of the river. Principal component analysis/factor analysis and correlation analysis revealed that three pollution sources (PS) may contribute to enriching the 11 examined elements in the sediment. These sources included (PS1) from catchment through water erosion over natural areas, explaining 83%, (PS2) mixed sources from catchment through water erosion over agricultural fields and inside Ho Chi Minh City, accounting for 6%, and (PS3) mixed sources from lowland areas, explaining 7.8% of the total variance of the elements. In brief, the sediment concentration of 11 metals and metalloid varied with season and space and three major pollution sources from river catchment, inside Ho Chi Minh City, and lowland contributively enriched the elements in the sediment of the River., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2020
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33. Hazardous heavy metals contamination of vegetables and food chain: Role of sustainable remediation approaches - A review.
- Author
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Kumar S, Prasad S, Yadav KK, Shrivastava M, Gupta N, Nagar S, Bach QV, Kamyab H, Khan SA, Yadav S, and Malav LC
- Subjects
- Biodegradation, Environmental, Environmental Restoration and Remediation methods, Food Chain, Food Contamination, Metals, Heavy, Soil Pollutants, Vegetables chemistry
- Abstract
This review emphasizes the role of toxic metal remediation approaches due to their broad sustainability and applicability. The rapid developmental processes can incorporate a large quantity of hazardous and unseen heavy metals in all the segments of the environment, including soil, water, air and plants. The released hazardous heavy metals (HHMs) entered into the food chain and biomagnified into living beings via food and vegetable consumption and originate potentially health-threatening effects. The physical and chemical remediation approaches are restricted and localized and, mainly applied to wastewater and soils and not the plant. The nanotechnological, biotechnological and genetical approaches required to more rectification and sustainability. A cellular, molecular and nano-level understanding of the pathways and reactions are responsible for potentially toxic metals (TMs) accumulation. These approaches can enable the development of crop varieties with highly reduced concentrations of TMs in their consumable foods and vegetables. As a critical analysis by authors observed that nanoparticles could provide very high adaptability for both in-situ and ex-situ remediation of hazardous heavy metals (HHMs) in the environment. These methods could be used for the improvement of the inbuilt genetic potential and phytoremediation ability of plants by developing transgenic. These biological processes involve the transfer of gene of interest, which plays a role in hazardous metal uptake, transport, stabilization, inactivation and accumulation to increased host tolerance. This review identified that use of nanoremediation and combined biotechnological and, transgenic could help to enhance phytoremediation efficiency in a sustainable way., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2019
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34. Seasonal, Spatial Variation, and Potential Sources of Organochlorine Pesticides in Water and Sediment in the Lower Reaches of the Dong Nai River System in Vietnam.
- Author
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Nguyen TX, Nguyen BT, Tran HTT, Mai H, Duong TT, and Bach QV
- Subjects
- DDT analysis, Environmental Monitoring, Hexachlorocyclohexane analysis, Principal Component Analysis, Rain, Seasons, Spatio-Temporal Analysis, Vietnam, Geologic Sediments analysis, Hydrocarbons, Chlorinated analysis, Pesticides analysis, Rivers chemistry, Water Pollutants, Chemical analysis
- Abstract
The goals of the current study were (1) to examine seasonal and spatial variation of selected OCPs concentrations and (2) to identify potential sources of the pollutants in the lower reaches of the Dong Nai River system. Forty-eight water and sediment samples were taken from 12 stations in the dry and rainy seasons to determine the concentrations of dichlorodiphenyltrichloroethane and its metabolites (total DDTs), hexachlorocyclohexane isomers (total HCHs), heptachlor, aldrin, dieldrin, and endrin. The concentrations of total DDTs (0.30), total HCHs (0.29), Aldrin (0.068), heptachlor (0.04, µg L
-1 ) in water, and total DDTs (8.04), total HCHs (4.51), and Aldrin (1.52, µg kg-1 ) in sediment were significantly higher in the rainy season than in the dry season (0.14, 0.12, 0.008, 0.009 in water and 3.49, 2.29, and 0.4 in sediment, respectively). Cluster analysis grouped 12 sampling stations into 2 groups, of which group 1 (3 stations) had higher concentrations of total DDTs, total HCHs, Aldrin, heptachlor, and dieldrin in both water and sediment than in group 2. Compositional analysis of total DDTs revealed that DDT residue could be decomposed significantly for the past years and that anaerobic decomposition could be predominant. Principal component analysis/factor analysis (PCA/FA) indicated that the potential sources of OCPs in the study stations could come from residential and agricultural areas located in the upper catchment or areas surrounding the studied stations. In short, OCPs concentration in the studies area could depend on seasonal, spatial variation, and transport of OCPs from upper parts or surrounding areas.- Published
- 2019
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35. Antimicrobial Lavandulylated Flavonoids from a Sponge-Derived Streptomyces sp. G248 in East Vietnam Sea.
- Author
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Cao DD, Trinh TTV, Mai HDT, Vu VN, Le HM, Thi QV, Nguyen MA, Duong TT, Tran DT, Chau VM, Ma R, Shetye G, Cho S, Murphy BT, and Pham VC
- Subjects
- Animals, Antibiotics, Antitubercular chemistry, Antibiotics, Antitubercular isolation & purification, Cell Line, Tumor, Circular Dichroism, Flavonoids chemistry, Flavonoids isolation & purification, Magnetic Resonance Spectroscopy, Microbial Sensitivity Tests, Molecular Structure, Mycobacterium tuberculosis drug effects, Spectrometry, Mass, Electrospray Ionization, Vietnam, Antibiotics, Antitubercular pharmacology, Flavonoids pharmacology, Porifera microbiology, Streptomyces chemistry
- Abstract
Three new lavandulylated flavonoids, (2 S ,2'' S )-6-lavandulyl-7,4'-dimethoxy-5,2'-dihydroxylflavanone ( 1 ), (2 S ,2'' S )-6-lavandulyl-5,7,2',4'-tetrahydroxylflavanone ( 2 ), and (2'' S )-5'-lavandulyl-2'-methoxy-2,4,4',6'-tetrahydroxylchalcone ( 3 ), along with seven known compounds 4 - 10 were isolated from culture broth of Streptomyce s sp. G248. Their structures were established by spectroscopic data analysis, including 1D and 2D nuclear magnetic resonance (NMR), and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS). The absolute configurations of 1 - 3 were resolved by comparison of their experimental and calculated electronic circular dichroism spectra. Compounds 1 - 3 exhibited remarkable antimicrobial activity. Whereas, two known compounds 4 and 5 exhibited inhibitory activity against Mycobacterium tuberculosis H37Rv with minimum inhibitory concentration (MIC) values of 6.0 µg/mL and 11.1 µg/mL, respectively., Competing Interests: The authors declare no conflicts of interest
- Published
- 2019
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36. Enhancement of dairy sheep cheese eating quality with increased n-3 long-chain polyunsaturated fatty acids.
- Author
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Nguyen QV, Van Le H, Nguyen DV, Malau-Aduli BS, Nichols PD, and Malau-Aduli AEO
- Subjects
- Animals, Breeding, Dairying, Diet veterinary, Docosahexaenoic Acids analysis, Eicosapentaenoic Acid analogs & derivatives, Fatty Acids, Unsaturated analysis, Female, Linseed Oil administration & dosage, Linseed Oil chemistry, Milk chemistry, Plant Oils administration & dosage, Pregnancy, Rumen metabolism, alpha-Linolenic Acid analysis, Animal Feed analysis, Cheese analysis, Fatty Acids, Omega-3 analysis, Sheep metabolism
- Abstract
This study investigated the effect of different plant oil-infused and rumen-protected wheat-based pellets containing eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) on n-3 long-chain (≥C
20 ) polyunsaturated fatty acid (LC-PUFA) content, fatty acid recovery, and sensory attributes of ripened cheese from dairy sheep. During a 10-wk supplementary feeding trial, 60 dairy ewes balanced by live weight, milk yield, parity, and sire breed were randomly divided into 6 groups that were (1) supplemented with on-farm existing commercial wheat-based pellets without oil inclusion (control) or supplemented with wheat-based pellets infused with 50 mL/kg dry matter of oils from (2) canola, (3) rice bran, (4) flaxseed, (5) safflower, and (6) rumen-protected EPA + DHA. Milk samples from each treatment were collected separately by sire breed during the experimental period for cheese processing at the end of the experiment. Twelve batches of cheese (2 batches per treatment) were processed and ripened for 120 d. Three cheese samples were collected and analyzed for each cheese making session (total of 36 cheese samples) at d 120 of ripening. Processed cheese of rumen-protected EPA + DHA had the most efficiency at elevating total n-3 LC-PUFA [total EPA + DHA + docosapentaenoic acid (DPA, 22:5n-3] content compared with the control (0.49 vs. 0.28%). Flaxseed elicited the greatest enhancement of α-linolenic acid (ALA, 18:3n-3), whereas safflower was the most effective diet in enhancing the level of linoleic acid (18:2n-6) in cheese (1.29 vs. 0.71% and 4.8 vs. 3.3%, respectively). Parallel recoveries of n-3 and n-6 LC-PUFA were observed across all treatments except for α-linolenic acid and EPA. Cheese eating sensory traits were also highly affected by oil supplementation, with the highest score of 7.5 in cheese from the rice bran and flaxseed treatments. These results provide new insights into the biological mechanisms and processes that determine dairy ewe milk productivity by underpinning the vital biological role of n-3 LC-PUFA in not only enhancing the healthy composition of cheese from ewes but also translating it into consumer acceptability., (Copyright © 2019 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)- Published
- 2019
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37. Novel HAX1 Gene Mutation in a Vietnamese Boy with Severe Congenital Neutropenia.
- Author
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Tran TT, Vu QV, Wada T, Yachie A, Le Thi Minh H, and Nguyen SN
- Abstract
Severe congenital neutropenia (SCN) is a rare disease that involves a heterogeneous group of hereditary diseases. Mutations in the HAX1 gene can cause an autosomal recessive form of SCN-characterized low blood neutrophil count from birth, increased susceptibility to recurrent and life-threatening infections, and preleukemia predisposition. A 7-year-old boy was admitted due to life-threatening infections, mental retardation, and severe neutropenia. He had early-onset bacterial infections, and his serial complete blood count showed persistent severe neutropenia. One older sister and one older brother of the patient died at the age of 6 months and 5 months, respectively, because of severe infection. Bone marrow analysis revealed a maturation arrest at the promyelocyte/myelocyte stage with few mature neutrophils. In direct DNA sequencing analysis, we found a novel homozygous frameshift mutation (c.423_424insG, p.Gly143fs) in the HAX1 gene, confirming the diagnosis of SCN. The patient was successfully treated with granulocyte colony-stimulating factor (G-CSF) and antibiotics. A child with early-onset recurrent infections and neutropenia should be considered to be affected with SCN. Genetic analysis is useful to confirm diagnosis. Timely diagnosis and suitable treatment with G-CSF and antibiotics are important to prevent further complication.
- Published
- 2018
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38. Synthesis and Irreversible Thermochromic Sensor Applications of Manganese Violet.
- Author
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Nguyen DK, Bach QV, Lee JH, and Kim IT
- Abstract
An irreversible thermochromic material based on manganese violet (MnNH₄P₂O₇) is synthesized. The crystal phase, chemical composition, and morphology of the synthesized material are analyzed using X-ray diffraction, scanning electron microscopy coupled with energy-dispersive X-ray spectrometry, and Fourier-transform infrared spectroscopy. The absorption spectra of the synthesized material are obtained using a UV-Vis spectrometer, and the thermochromism exhibited by the powdered samples at high temperatures is also investigated. The as-synthesized manganese violet pigment consists of pure α-MnNH₄P₂O₇ phase. In addition, the synthesized pigment largely consists of hexagonal crystals with a diameter of hundreds of nanometers. On heating, the pigment simultaneously loses H₂O and NH₃ in two successive steps at approximately 330⁻434.4 °C and 434.4⁻527 °C, which correspond to the formation of an intermediate phase and of Mn₂P₄O
12 , respectively. An overall mass loss of 14.22% is observed, which is consistent with the expected 13.79%. An irreversible color change from violet to white is observed after exposure of the synthesized manganese violet pigment at 400 °C for 30 min. This is attributed to the oxidation of ammonia to hydroxylamine, which then decomposes to nitrogen and water, or alternatively to the direct oxidation of ammonia to nitrogen. Furthermore, we demonstrate the potential application of synthesized manganese violet in the production of irreversible thermochromic paint by mixing with potassium silicate solution as a binder and deionized water as a solvent at a specific ratio. The thermochromic paint is then applied in fabrication of irreversible thermochromic sensors by coating it onto a steel plate surface. Finally, we show that manganese violet-based irreversible thermochromic sensors are able to detect temperatures around 400 °C by changing color from violet to white/milky.- Published
- 2018
- Full Text
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39. Pyrolysis characteristics and kinetics of microalgae via thermogravimetric analysis (TGA): A state-of-the-art review.
- Author
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Bach QV and Chen WH
- Subjects
- Kinetics, Plant Oils, Polyphenols, Thermogravimetry, Biofuels, Microalgae
- Abstract
Pyrolysis is a promising route for biofuels production from microalgae at moderate temperatures (400-600°C) in an inert atmosphere. Depending on the operating conditions, pyrolysis can produce biochar and/or bio-oil. In practice, knowledge for thermal decomposition characteristics and kinetics of microalgae during pyrolysis is essential for pyrolyzer design and pyrolysis optimization. Recently, the pyrolysis kinetics of microalgae has become a crucial topic and received increasing interest from researchers. Thermogravimetric analysis (TGA) has been employed as a proven technique for studying microalgae pyrolysis in a kinetic control regime. In addition, a number of kinetic models have been applied to process the TGA data for kinetic evaluation and parameters estimation. This paper aims to provide a state-of-the art review on recent research activities in pyrolysis characteristics and kinetics of various microalgae. Common kinetic models predicting the thermal degradation of microalgae are examined and their pros and cons are illustrated., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2017
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40. Gasification kinetics of raw and wet-torrefied microalgae Chlorella vulgaris ESP-31 in carbon dioxide.
- Author
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Bach QV, Chen WH, Sheen HK, and Chang JS
- Subjects
- Biomass, Kinetics, Microalgae, Thermogravimetry, Carbon Dioxide, Chlorella vulgaris
- Abstract
This study aims at investigating the gasification behavior and kinetics of microalga Chlorella vulgaris ESP-31 before and after wet torrefaction. The raw and wet-torrefied microalgae were first gasified in a thermogravimetric analyzer under a continuous CO
2 flow. Thereafter, the obtained thermogravimetric data were modeled for kinetic study, employing a seven-parallel-reaction mechanism. The decomposition of the microalgae in CO2 shows two reactive stages: devolatilization with two peaks and gasification with a peak accompanied by a shoulder, and the thermal decomposition of components in the samples can be clearly identified. Increasing wet torrefaction temperature lowers the height of the major devolatilization peak but enhances the height of the minor one. Moreover, the kinetic evaluation reveals that wet torrefaction affects most of the kinetic parameters of the microalgal components. Furthermore, wet torrefaction temperature influences the kinetic parameters of carbohydrate and lipid, but not on those of protein, "others", and chars., (Copyright © 2017 Elsevier Ltd. All rights reserved.)- Published
- 2017
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41. Predictions of biochar yield and elemental composition during torrefaction of forest residues.
- Author
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Bach QV, Chen WH, Chu YS, and Skreiberg Ø
- Subjects
- Betula chemistry, Biofuels analysis, Biomass, Charcoal analysis, Conservation of Natural Resources, Forestry, Forests, Kinetics, Models, Chemical, Picea chemistry, Thermogravimetry, Charcoal chemistry, Plant Components, Aerial chemistry
- Abstract
In this work, a direct prediction method coupled with a consecutive reaction model is developed to estimate the biochar yield and elemental composition in a biomass torrefaction process. Norway forest residues were chosen as feedstock and torrefied at different temperatures under nitrogen atmosphere in a thermogravimetric analyzer. Obtained data were modeled to predict the mass loss during torrefaction. Distributions of initial, intermediate and final solid products as well as torrefaction kinetic parameters are reported. Thereafter, a direct method to predict the elemental composition of biochar is introduced. The results show that the decomposition of initial biomass to form an intermediate solid has higher conversion rate than the degradation of the intermediate. Moreover, the predictions reproduce well the experimental thermogravimetric curves and show composition trends similar to the literature data. This method is useful for the design and optimization of industrial torrefaction processes with predictable biochar yield and elemental composition., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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42. Secondary Metabolites from an Actinomycete from Vietnam's East Sea.
- Author
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Thi QV, Tran VH, Mai HD, Le CV, Hong Mle T, Murphy BT, Chau VM, and Pham VC
- Subjects
- Actinobacteria chemistry, Anti-Bacterial Agents chemistry, Antifungal Agents chemistry, Antineoplastic Agents chemistry, Molecular Structure, Oceans and Seas, Seawater microbiology, Vietnam, Water Microbiology, Actinobacteria metabolism, Anti-Bacterial Agents pharmacology, Antifungal Agents pharmacology, Antineoplastic Agents pharmacology
- Abstract
Analysis of an antimicrobial extract prepared from culture broth of the marine-derived actinomycete Nocardiopsis sp. (strain G057) led to the isolation of twelve compounds, 1-12. Compound 1 (2-[(2R-hydroxypropanoyl)amino]benzamide) was found to be a new enantiomeric isomer while compounds 2 (3-acetyl-4-hydroxycinnoline) and 3 (3,3'-bis-indole) were isolated from a natural source for the first time. The structures of 1-12 were determined by analyses of MS and 2D NMR data. All compounds were evaluated for their antimicrobial activity against a panel of clinically significant microorganisms. Compound 1 selectively inhibited Escherichia coli (MIC: 16 µg/mL). Compounds 2 and 3 exhibited antimicrobial activity against several strains of both Gram-positive and Gram-negative bacteria, and the yeast Candida albicans. Cytotoxic evaluation of compounds 1-3 against four cancer cell lines (KB, LU-1, HepG-2 and MCF-7) indicated that compound 3 produced a weak inhibition against KB and LU cell lines. Two remaining compounds, 1 and 2 were not cytotoxic, even at the concentration of 128 µg/mL.
- Published
- 2016
43. Antimicrobial Metabolites from a Marine-Derived Actinomycete in Vietnam's East Sea.
- Author
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Thi QV, Tran VH, Maia HD, Le CV, Hong Mle T, Murphy BT, Chau VM, and Pham VC
- Subjects
- Actinobacteria chemistry, Actinobacteria genetics, Alcohols chemistry, Alcohols metabolism, Alkaloids chemistry, Alkaloids metabolism, Anti-Bacterial Agents chemistry, Antifungal Agents chemistry, Bacteria drug effects, Candida albicans drug effects, Dioxanes chemistry, Dioxanes metabolism, Ethanol chemistry, Ethanol metabolism, Ethanol pharmacology, Geologic Sediments microbiology, Microbial Sensitivity Tests, Molecular Structure, Oceans and Seas, Quinolines chemistry, Quinolines metabolism, Vietnam, Actinobacteria metabolism, Alcohols pharmacology, Alkaloids pharmacology, Anti-Bacterial Agents metabolism, Antifungal Agents metabolism, Dioxanes pharmacology, Ethanol analogs & derivatives, Quinolines pharmacology
- Abstract
Two new compounds, a quinoline alkaloid (1) and a 1,4-dioxane derivative (2), were isolated from culture broth of the marine-derived actinomycete Micromonospora sp. (strain G019) by bioassay-guided fractionation. This actinomycete strain was isolated from sediment, collected at Cát Bà Peninsula, Vietnam. The taxonomic identification was achieved by analysis of 16S rRNA gene sequences. On the basis of morphological and phylogenetic evidence, strain G019 was assigned to the genus Micromonospora. The structures of 1 and 2 were established by spectroscopic data analysis, including one- and two-dimensional NMR, and MS. Compound 1 was found to have antibacterial activity against Escherichia coli (MIC: 48 µg/mL), Salmonella enterica (MIC: 96 µg/mL) and Enterococcus faecalis (MIC: 128 µg/mL), while compound 2 showed inhibitory activity against Enterococcusfaecalis (MIC: 32 µg/mL) and Candida albicans (MIC: 64 µg/mL).
- Published
- 2016
44. Development of a biomass torrefaction process integrated with oxy-fuel combustion.
- Author
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Tran KQ, Trinh TN, and Bach QV
- Subjects
- Biomass, Carbon Dioxide chemistry, Forestry, Nitrogen chemistry, Picea, Biofuels, Biotechnology methods
- Abstract
Torrefaction of forest residues was studied under conditions relevant to oxy-fuel combustion flue gases. The results showed that the torrefaction in CO2 had a lower solid mass yield (81.36%) than that (83.06%) in N2. Addition of steam into CO2 (CO2/H2O=1/0.7 mole/mole) resulted in a higher mass yield (83.30%) compared to 81.36% in CO2. The energy yield was consistently increased from 79.17% to 84.12% or 88.32% for the torrefaction in N2, CO2, or the CO2 and steam mixture, respectively. On the other hand, additions of O2 into the mixture of steam and CO2 led to reductions in both mass yield (from 83.30% to 82.57% or 76.44%) and energy yield (from 88.32% to 84.65% or 79.16%, for the torrefaction in steam and CO2 without O2, with 5% v/v, or 10% v/v of O2, respectively)., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Published
- 2016
- Full Text
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45. Severe congenital neutropenia caused by the ELANE gene mutation in a Vietnamese boy with misdiagnosis of tuberculosis and autoimmune neutropenia: a case report.
- Author
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Vu QV, Wada T, Tran TT, Ngo DN, Van Dinh T, Nguyen CH, Le HT, Yachie A, and Nguyen SN
- Abstract
Background: Severe congenital neutropenia (SCN) is an immunodeficiency disease characterized low blood neutrophil counts, early bacterial infections, and risk of leukaemia development. Heterozygous mutations in the ELANE gene coding neutrophil elastase are associated with SCN. Patients with SCN suffer from recurrent bacterial infections and often succumb them. To our knowledge, this is the first report of SCN from Vietnam., Case Presentation: A 6-year-old boy was admitted due to severe bacterial infection and severe neutropenia. He had recurrent infections from 8 months of age, and was misdiagnosed with tuberculosis and and autoimmune neutropenia in infancy at 21 and 41 months of age, respectively. His medical report has showed severe neutropenia for many times. In direct DNA sequencing analysis, we found an ELANE gene mutation (R81P), which had been confirmed to cause SCN., Conclusion: The missed and delayed diagnosis may be attributable to insufficient awareness of this rare disease on the background of frequent infections even in the immunocompetent pediatric population in Vietnam. Our results indicate further evidence for the role of ELANE in SCN.
- Published
- 2015
- Full Text
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46. Clinical and mutational features of Vietnamese children with X-linked agammaglobulinemia.
- Author
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Vu QV, Wada T, Le HT, Le HT, Van Nguyen AT, Osamu O, Yachie A, and Nguyen SN
- Subjects
- Agammaglobulinaemia Tyrosine Kinase, Arthritis complications, B-Lymphocytes metabolism, Bronchiectasis complications, CD4-CD8 Ratio, Child, Child, Preschool, Diarrhea complications, Humans, Male, Meningitis complications, Neutropenia etiology, Otitis Media complications, Pneumonia complications, Sepsis complications, Sinusitis complications, Skin Diseases, Infectious complications, Vietnam, Agammaglobulinemia diagnosis, Agammaglobulinemia genetics, Codon, Nonsense, Frameshift Mutation, Genetic Diseases, X-Linked diagnosis, Genetic Diseases, X-Linked genetics, Protein-Tyrosine Kinases genetics
- Abstract
Background: X-linked agammaglobulinemia (XLA) is a primary immune deficiency characterized by recurrent bacterial infections and profoundly depressed serum immunoglobulin levels and circulating mature B cells. It is caused by mutations of the Bruton tyrosine kinase (BTK) gene and is the most common form of inherited antibody deficiency. To our knowledge, this is the first report of XLA from Vietnam., Methods: We investigated the BTK gene mutations and clinical features of four unrelated Vietnamese children., Results: The mean ages at onset and at diagnosis were 2.5 and 8 years, respectively. All patients had a medical history of otitis media, pneumonia, and septicemia at the time of diagnosis. Other infections reported included sinusitis, bronchiectasis, arthritis, skin infections, meningitis, and recurrent diarrhea. We identified one previously reported mutation (c.441G >A) and three novel mutations: two frameshifts (c.1770delG and c.1742 delG), and one nonsense (c.1249A >T)., Conclusions: The delayed diagnosis may be attributable to insufficient awareness of this rare disease on the background of frequent infections even in the immunocompetent pediatric population in Vietnam. Our results further support the importance of molecular genetic testing in diagnosis of XLA.
- Published
- 2014
- Full Text
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47. Annealing temperature and environment effects on ZnO nanocrystals embedded in SiO2: a photoluminescence and TEM study.
- Author
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Pita K, Baudin P, Vu QV, Aad R, Couteau C, and Lérondel G
- Abstract
We report on efficient ZnO nanocrystal (ZnO-NC) emission in the near-UV region. We show that luminescence from ZnO nanocrystals embedded in a SiO2 matrix can vary significantly as a function of the annealing temperature from 450°C to 700°C. We manage to correlate the emission of the ZnO nanocrystals embedded in SiO2 thin films with transmission electron microscopy images in order to optimize the fabrication process. Emission can be explained using two main contributions, near-band-edge emission (UV range) and defect-related emissions (visible). Both contributions over 500°C are found to be size dependent in intensity due to a decrease of the absorption cross section. For the smallest-size nanocrystals, UV emission can only be accounted for using a blueshifted UV contribution as compared to the ZnO band gap. In order to further optimize the emission properties, we have studied different annealing atmospheres under oxygen and under argon gas. We conclude that a softer annealing temperature at 450°C but with longer annealing time under oxygen is the most preferable scenario in order to improve near-UV emission of the ZnO nanocrystals embedded in an SiO2 matrix.
- Published
- 2013
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48. Clinical and immunophenotypic features of atypical complete DiGeorge syndrome.
- Author
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Vu QV, Wada T, Toma T, Tajima H, Maeda M, Tanaka R, Oh-Ishi T, and Yachie A
- Subjects
- Biomarkers blood, DiGeorge Syndrome immunology, Flow Cytometry, Humans, Infant, Newborn, Lymphocyte Count, Male, Receptors, Antigen, T-Cell, alpha-beta blood, T-Lymphocytes metabolism, DiGeorge Syndrome diagnosis
- Abstract
Background: DiGeorge syndrome is a congenital malformation characterized by variable defects of the thymus, heart and parathyroid glands. Athymic patients are classified as exhibiting complete DiGeorge syndrome. Some of these patients may also exhibit oligoclonal T-cell expansion, generalized rash and lymphadenopathy at some point after birth. This rare condition is known as atypical complete DiGeorge syndrome, resembles Omenn syndrome, and has not been fully characterized., Methods: The clinical and immunophenotypic features of atypical complete DiGeorge syndrome were assessed in two affected Japanese infants. T-cell receptor (TCR) Vβ repertoire was analyzed on flow cytometry and complementarity-determining region 3 spectratyping., Results: Both patients had no detectable thymus tissue and profound T-cell lymphopenia soon after birth. Progressive increase of activated T cells, however, as well as eosinophilia, high serum IgE level, generalized rash, and lymphadenopathy were observed during early infancy. A highly restricted TCR Vβ repertoire was demonstrated both in CD4(+) and CD8(+) T cells., Conclusions: The Omenn syndrome-like manifestations might be associated with the oligoclonal proliferation of activated T cells. Analysis of the immunophenotype and TCR Vβ repertoire is helpful to establish the early diagnosis of atypical complete DiGeorge syndrome., (© 2012 The Authors. Pediatrics International © 2012 Japan Pediatric Society.)
- Published
- 2013
- Full Text
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49. Cross sectional: normal maximal incisal opening and associations with physical variables in children.
- Author
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Ying QV, Bacic J, Abramowicz S, and Sonis A
- Subjects
- Adolescent, Black or African American, Age Factors, Body Height, Body Weight, Child, Child Development, Child, Preschool, Cross-Sectional Studies, Dental Occlusion, Female, Hispanic or Latino, Humans, Male, Molar anatomy & histology, Open Bite pathology, Overbite pathology, Sex Factors, White People, Incisor anatomy & histology, Range of Motion, Articular physiology, Temporomandibular Joint physiology
- Abstract
Purpose: The purpose of this investigation was to establish a normal range of maximal incisal opening (MIO) in children, and the correlation between MIO with age, height, weight, gender, race, and molar relationship., Methods: Calibrated examiners used the TheraBite Range of Motion (ROM) scale to obtain two MIO readings from 500 enrolled subjects, accounting for overbite or open bite. The subject's height, weight, molar relationship, age, gender, and race were recorded. Subjects were stratified according to age, and mean MIO ± standard deviation for each age group was determined., Results: Mean MIO was positively correlated with age (P<.001), height (P<.001), weight (P<.001), and race (P<.001). However, height became insignificant in the multivariable regression model. On average, MIO of African-Americans was 3.66 mm larger than Whites (P<.001), and MIO of Hispanics/Latinos was 2.52mm greater than Whites (P<.001). There was no statistically significant association with left or right molar relationships (P=.07, P=.26 respectively) or gender (P=.58)., Conclusions: TheraBite ROM scale is a practical tool to clinically measure MIO. MIO mimics somatic growth, peaking at age 12-13 years for females and 14-15 years for males. African-Americans and Hispanics/Latinos have a greater mean MIO than Whites. The established norms will be useful in diagnosis and treatment.
- Published
- 2013
50. A case of acute encephalopathy with hemophagocytic lymphohistiocytosis and clonal T-cell expansion.
- Author
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Wada T, Nishiura K, Kuroda M, Asai E, Vu QV, Toma T, Niida Y, and Yachie A
- Subjects
- Child, Cytokines blood, Encephalitis immunology, Humans, Lymphocyte Activation immunology, Lymphohistiocytosis, Hemophagocytic immunology, Male, CD8-Positive T-Lymphocytes immunology, Encephalitis complications, Lymphohistiocytosis, Hemophagocytic complications
- Abstract
We report on a 9-year-old boy who presented with acute encephalopathy and hemophagocytic lymphohistiocytosis (HLH). The patient was referred to our hospital because of fever, seizures, and decreased consciousness. He showed moderately elevated levels of proinflammatory cytokines in the cerebrospinal fluid and plasma, and clonal expansion of highly activated CD8⁺ T cells in the peripheral blood. These CD8⁺ T cells were found to be larger cells that stained positive for T-cell receptor Vβ13.6, and decreased shortly after steroid therapy. Our findings suggest that his acute encephalopathy was likely a clinical manifestation of HLH, and that immunophenotypic analysis may be helpful for early recognition of HLH in such rare encephalopathy., (Copyright © 2011 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.)
- Published
- 2012
- Full Text
- View/download PDF
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