1.Characteristics of Immunogenicity against SARS-CoV-2in a Community-Based Model of Care during the Fourth Wave of COVID-19 Outbreak in Ho Chi Minh City
Tu Hoang KIM TRINH ; Tuan Diep TRAN ; Duy Le PHAM ; Vinh Nhu NGUYEN ; Quan Tran THIEN VU ; Toan Duong PHAM ; Phong Hoai NGUYEN ; Minh Kieu LE ; Diem Dinh KIEU TRUONG ; Vu Anh HOANG ; Nghia HUYNH ; Dat Quoc NGO ; Lan Ngoc VUONG
Yonsei Medical Journal 2024;65(9):501-510
Purpose:
Although some immune protection from close contact with individuals who have coronavirus disease 2019 (COVID-19) has been documented, there is limited data on the seroprevalence of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in individuals who were in lockdown with confirmed COVID-19 cases. This study investigated immunogenicity against SARS-CoV-2 in household members and people who lived near home-quarantined patients with COVID-19.
Materials and Methods:
This cross-sectional study was conducted during the community-based care that took place during lockdowns in District 10, Ho Chi Minh City, Vietnam from July to September 2021. SARS-CoV-2 antibody levels were determined in index cases of COVID-19, household contacts, and a no-contact group from the same area.
Results:
A total of 770 participants were included (355 index cases, 103 household contacts, and 312 no contacts). All index cases were unvaccinated, but >90% of individuals in the household and no-contact groups had received ≥1 vaccine dose. SARS-CoV-2 neutralizing antibodies (Nabs) were present in >77% of unvaccinated index cases versus 64%/65.4% in the householdo-contact groups (p=0.001). Antibody concentrations in unvaccinated index cases were significantly higher than those in household contacts and no contacts, with no difference between the latter groups. In all cases, antibody levels declined markedly ≥6 weeks after infection, and failed to persist beyond this time in the household and no-contact groups.
Conclusion
Community-based care may have helped to create community immunogenicity, but Nabs did not persist, highlighting a need for vaccination for all individuals before, or from 6 weeks after, infection with SARS-CoV-2.
2.Prevalence and risk factors for human papillomavirus infection among female sex workers in Hanoi and Ho Chi Minh City, Viet Nam: a cross-sectional study
Quang Duy Pham ; Kiesha Prem ; Tuan Anh Le ; Nguyen Van Trang ; Mark Jit ; Tuan Anh Nguyen ; Van Cao ; Tam-Duong Le-Ha ; Mai Thi Ngoc Chu ; Ly Thi Khanh Le ; Zheng Quan Toh ; Marc Brisson ; Suzanne Garland ; Gerald Murray ; Kathryn Bright ; Duc Anh Dang ; Hau Phuc Trana ; Edward Kim Mulholland
Western Pacific Surveillance and Response 2022;13(4):1-11
Objective:
Female sex workers (FSWs) are at high risk of human papillomavirus (HPV) infections and cervical cancer due to their high number of sexual partners. The objectives of this study were to determine the prevalence of HPV and identify risk factors for high-risk HPV infection among FSWs in Hanoi and Ho Chi Minh City (HCMC), Viet Nam.
Methods:
A cross-sectional study was conducted in Hanoi and HCMC between December 2017 and May 2018. We surveyed and screened 699 FSWs aged ≥18 years for HPV infection and abnormal cytology. A multivariable modified Cox regression model was used to determine risk factors for high-risk HPV infection.
Results
The overall prevalence of any HPV, high-risk HPV and HPV-16/18 infection in the 699 FSWs was 26.3%, 17.6% and 4.0%, respectively, and were similar in both cities. Multiple infections were identified in 127 participants (69.0%).HPV-52 was the most prevalent (7%), followed by HPV-58 (6%). Abnormal cytology was detected in 91 participants (13.0%). FSWs who are divorced (adjusted prevalence ratio [aPR]: 1.96, 95% confidence interval [CI]: 1.01–3.81), widowed (aPR: 3.26, 95% CI: 1.49–7.12) or living alone (aPR: 1.85, 95% CI: 1.01–3.39) were associated with a higher prevalence of high-risk HPV infection.
3.Removal of Manganese and Copper from Aqueous Solution by Yeast Papiliotrema huenov
Phu Nguyen VAN ; Hai Thi Hong TRUONG ; Tuan Anh PHAM ; Tuan Le CONG ; Tien LE ; Kim Cuc Thi NGUYEN
Mycobiology 2021;49(5):507-520
Papiliotrema huenov was previously reported to be highly tolerant of a range of extremely toxic heavy metals. This study aimed to identify the potential of P. huenov to remove manganese and copper from aqueous solution. Physical conditions which affect removal of Mn(II) and Cu(II) were determined. Optimal temperature for adsorption of both metal ions was 30°C, and optimal pH for maximum uptake of Mn(II) and Cu(II) were 5 and 6, respectively. Under these conditions, living cells of P. huenov accumulated up to 75.58% of 110 mg/ L Mn(II) and 70.5% of 128 mg/L Cu(II) over 120 h, whereas, the removal efficiency of metal ions by dead cells over 1 h was 60.3% and 56.5%, respectively. These results indicate that living cells are more effective than dead biomass for bioremediation, but that greater time is required. The experimental data extends the potential use of P. huenov in biosorption and bioaccumulation of toxic heavy metals to copper and manganese, two of the most common industrial contaminants.
4.Identification of Soluble Epoxide Hydrolase Inhibitors from the Seeds of Passiflora edulis Cultivated in Vietnam
To Dao CUONG ; Hoang THI NGOC ANH ; Tran Thu HUONG ; Pham Ngoc KHANH ; Vu Thi HA ; Tran Manh HUNG ; Young Ho KIM ; Nguyen Manh CUONG
Natural Product Sciences 2019;25(4):348-353
Soluble epoxide hydrolases (sEH) are enzymes present in all living organisms, metabolize epoxy fatty acids to 1,2-diols. sEH in the metabolism of polyunsaturated fatty acids plays a key role in inflammation. In addition, the endogenous lipid mediators in cardiovascular disease are also broken down to diols by the action of sEH that enhanced cardiovascular protection. In this study, sEH inhibitory guided fractionation led to the isolation of five phenolic compounds trans-resveratrol (1), trans-piceatannol (2), sulfuretin (3), (+)-balanophonin (4), and cassigarol E (5) from the ethanol extract of the seeds of Passiflora edulis Sims cultivated in Vietnam. The chemical structures of isolated compounds were determined by the interpretation of NMR spectral data, mass spectra, and comparison with data from the literature. The soluble epoxide hydrolase (sEH) inhibitory activity of isolated compounds was evaluated. Among them, trans-piceatannol (2) showed the most potent inhibitory activity on sEH with an IC₅₀ value of 3.4 µM. This study marks the first time that sulfuretin (3) was isolated from Passiflora edulis as well as (+)-balanophonin (4), and cassigarol E (5) were isolated from Passiflora genus.
Cardiovascular Diseases
;
Epoxide Hydrolases
;
Ethanol
;
Fatty Acids
;
Fatty Acids, Unsaturated
;
Inflammation
;
Metabolism
;
Passiflora
;
Passifloraceae
;
Phenol
;
Vietnam
5. Ethanol extracts of Scutellaria baicalensis protect against lipopolysaccharideinduced acute liver injury in mice
Hai Nguyen THANH ; Tuan Anh LE ; Huong Duong Thi LY ; Tung Nguyen HUU ; Loi Vu DUC ; Thu Dang KIM ; Tung Bui THANH ; Hue Pham Thi MINH
Asian Pacific Journal of Tropical Biomedicine 2015;5(9):761-767
Objective: To investigated the protective potential of ethanol extracts of Scutellaria baicalensis (S. baicalensis) against lipopolysaccharide (LPS)-induced liver injury. Methods: Dried roots of S. baicalensis were extracted with ethanol and concentrated to yield a dry residue. Mice were administered 200 mg/kg of the ethanol extracts orally once daily for one week. Animals were subsequently administered a single dose of LPS (5 mg/kg of body weight, intraperitoneal injection). Both protein and mRNA levels of cytokines, such as tumor necrosis factor alpha, interleukin-1β, and interleukin-6 in liver tissues were evaluated by ELISA assay and quantitative PCR. Cyclooxygenase-2, inducible nitric oxide synthase, and nuclear factor-kB protein levels in liver tissues were analyzed by western blotting. Results: Liver injury induced by LPS significantly increased necrosis factor alpha, interleukin-1β, interleukin-6, cyclooxygenase-2, inducible nitric oxide synthase, and nuclear factor-κB in liver tissues. Treatment with ethanol extracts of S. baicalensis prevented all of these observed changes associated with LPS-induced injury in liver mice. Conclusions: Our study showed that S. baicalensis is potentially protective against LPSinduced liver injury in mice.
6.Alpha-Type 1 Polarized Dendritic Cells Loaded with Apoptotic Allogeneic Breast Cancer Cells Can Induce Potent Cytotoxic T Lymphocytes against Breast Cancer.
Min Ho PARK ; Deok Hwan YANG ; Mi Hyun KIM ; Jae Hong JANG ; Yoon Young JANG ; Youn Kyung LEE ; Chun Ji JIN ; Than Nhan Nguyen PHAM ; Truc Anh Nguyen THI ; Mi Seon LIM ; Hyun Ju LEE ; Cheol Yi HONG ; Jung Han YOON ; Je Jung LEE
Cancer Research and Treatment 2011;43(1):56-66
PURPOSE: Various tumor antigens can be loaded onto dendritic cells (DCs) to induce a potent cytotoxic T lymphocyte (CTL) response in DC-based immunotherapy against breast cancer. However, in the clinical setting, obtaining a sufficient number of autologous tumor cells as a source of tumor antigens is a laborious process. We therefore investigated the feasibility of immunotherapy using breast-cancer-specific CTLs generated in vitro by use of alpha-type 1 polarized DCs (alpha DC1s) loaded with ultraviolet B-irradiated cells of the breast cancer cell line MCF-7. MATERIALS AND METHODS: alphaDC1s were induced by loading allogeneic tumor antigen generated from the MCF-7 UVB-irradiated breast cancer cell line. Antigen-pulsed alphaDC1s were evaluated by morphological and functional assays, and the breast-cancer-specific CTL response was analyzed by cytotoxic assay. RESULTS: The alphaDC1s significantly increased the expression of several molecules related to DC maturation without differences according to whether the alphaDC1s were loaded with tumor antigens. The alphaDC1s showed a high production of interleukin-12 both during maturation and after subsequent stimulation with CD40L, which was not significantly affected by loading with tumor antigens. Breast-cancer-specific CTLs against autologous breast cancer cells were successfully induced by alphaDC1s loaded with apoptotic MCF-7 cells. CONCLUSION: Autologous DCs loaded with an allogeneic breast cancer cell line can generate potent breast-cancer-specific CTL responses. This may be a practical method for cellular immunotherapy in patients with breast cancer.
Antigens, Neoplasm
;
Breast
;
Breast Neoplasms
;
CD40 Ligand
;
Cell Line
;
Dendritic Cells
;
Humans
;
Immunotherapy
;
Interleukin-12
;
Lymphocytes
;
T-Lymphocytes, Cytotoxic
7.Improvement of Fungal Cellulase Production by Mutation and Optimization of Solid State Fermentation.
Van Hanh VU ; Tuan Anh PHAM ; Keun KIM
Mycobiology 2011;39(1):20-25
Spores of Aspergillus sp. SU14 were treated repeatedly and sequentially with Co60 gamma-rays, ultraviolet irradiation, and N-methyl-N'-nitro-N-nitrosoguanidine. One selected mutant strain, Aspergillus sp. SU14-M15, produced cellulase in a yield 2.2-fold exceeding that of the wild type. Optimal conditions for the production of cellulase by the mutant fungal strain using solid-state fermentation were examined. The medium consisted of wheat-bran supplemented with 1% (w/w) urea or NH4Cl, 1% (w/w) rice starch, 2.5 mM MgCl2, and 0.05% (v/w) Tween 80. Optimal moisture content and initial pH was 50% (v/w) and 3.5, respectively, and optimal aeration area was 3/100 (inoculated wheat bran/container). The medium was inoculated with 25% 48 hr seeding culture and fermented at 35degrees C for 3 days. The resulting cellulase yield was 8.5-fold more than that of the wild type strain grown on the basal wheat bran medium.
Aspergillus
;
Cellulase
;
Dietary Fiber
;
Fermentation
;
Hydrogen-Ion Concentration
;
Magnesium Chloride
;
Methylnitronitrosoguanidine
;
Polysorbates
;
Seeds
;
Spores
;
Sprains and Strains
;
Starch
;
Triticum
;
Urea
8.Enhancement of antitumor effect using dendritic cells activated with natural killer cells in the presence of Toll-like receptor agonist.
Thanh Nhan Nguyen PHAM ; Cheol Yi HONG ; Jung Joon MIN ; Joon Haeng RHEE ; Truc Anh Thi NGUYEN ; Byoung Chul PARK ; Deok Hwan YANG ; Young Kyu PARK ; Hyeong Rok KIM ; Ik Joo CHUNG ; Hyeoung Joon KIM ; Je Jung LEE
Experimental & Molecular Medicine 2010;42(6):407-419
Dendritic cells (DCs) play a role in natural killer (NK) cell activation, while NK cells are also able to activate and mature DCs. Toll-like receptors (TLRs) on the surface of DCs and NK cells induce the maturation and activation of these cells when engaged with their cognate ligand. We investigated to generate potent DCs by maturation with NK cells in the presence of TLR agonist in vitro and tested the efficacy of these DC vaccinations in mouse colon cancer model. The optimal ratios of DCs versus NK cells were 1:1 to 1:2. Immature DCs were mature with NK cells in the presence of lipopolysaccharide, which is TLR4 agonist, and further addition of IL-2 induced phenotypically and functionally mature bone marrow-derived DCs. These potent DCs exhibited not only high expression of several costimulatory molecules and high production of IL-12p40 and IL-12p70, but also high allogeneic T cells stimulatory capacity, and the induction of the high activities to generate tumor-specific CTLs. Consistently, vaccination with these DCs efficiently inhibited CT-26 tumor growth in mouse colon cancer model when compared to other vaccination strategies. Interestingly, combination therapy of these DC-based vaccines and with low-dose cyclophosphamide showed dramatic inhibition effects of tumor growth. These results suggest that the DCs maturated with NK cells in the presence of TLR agonist are potent inducer of antitumor immune responses in mouse model and may provide a new source of DC-based vaccines for the development of immunotherapy against colon cancer.
Animals
;
Cancer Vaccines/immunology/metabolism
;
Carcinoma/immunology/pathology/*therapy
;
Cell Line, Tumor
;
Cells, Cultured
;
Colonic Neoplasms/immunology/pathology/*therapy
;
Dendritic Cells/*drug effects/*immunology/transplantation
;
Female
;
Immunotherapy, Adoptive/*methods
;
Killer Cells, Natural/*immunology/physiology
;
Lipopolysaccharides/pharmacology
;
Mice
;
Mice, Inbred BALB C
;
Toll-Like Receptor 4/agonists
;
Toll-Like Receptors/*agonists
9.Optimization of Solid-State Fermentation for Improved Conidia Production of Beauveria bassiana as a Mycoinsecticide.
Tuan Anh PHAM ; Jeong Jun KIM ; Keun KIM
Mycobiology 2010;38(2):137-143
The production of conidia of entomopathogenic Beauveria bassiana by solid-state fermentation was studied for the development of a biocontrol agent against aphid Myzus persicae. The optimal conditions for conidia production on polished white rice were 40% moisture content, 25degrees C culture temperature, 2-day-old seeding culture grown in 3% corn meal, 2% rice bran, 2% corn steep powder medium, initial conidia concentration of 107 conidia/g in the wet rice, 10% inoculum size, and use of a polyethylene bag as a container. The polyethylene bag containing inoculated rice was hand-shaken every 12 hr during fermentation. Using optimal conditions, the maximum conidia production obtained was 4.05 g conidia/100 g dry rice after 14 days of cultivation, a rate 2.83 times higher than conidia yield of pre-optimization.
Aphids
;
Beauveria
;
Fermentation
;
Humans
;
Meals
;
Polyethylene
;
Seeds
;
Spores, Fungal
;
Zea mays
10.Fungal Strain Improvement for Cellulase Production Using Repeated and Sequential Mutagenesis.
Van Hanh VU ; Tuan Anh PHAM ; Keun KIM
Mycobiology 2009;37(4):267-271
A fungal strain producing a high level of cellulase was selected from 320 fungal isolates and identified as Aspergillus sp. This strain was further improved for cellulase production by sequential treatments by two repeated rounds of gamma-irradiation of Co60, ultraviolet treatment and four repeated rounds of treatment with N-methyl-N'-nitro-N-nitrosoguanidine. The best mutant strain, Aspergillus sp. XTG-4, was selected after screening and the activities of carboxymethyl cellulase, filter paper cellulase and beta-glucosidase of the cellulase were improved by 2.03-, 3.20-, and 1.80-fold, respectively, when compared to the wild type strain. After being subcultured 19 times, the enzyme production of the mutant Aspergillus sp. XTG-4s was stable.
Aspergillus
;
beta-Glucosidase
;
Cellulase
;
Mass Screening
;
Methylnitronitrosoguanidine
;
Mutagenesis
;
Sprains and Strains

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