1.Cloning of the gene encoding human recombinant blood \u2013 coagulation factor WIII
Thuy Thu Nguyen ; Khanh Van Tran ; Khoa Dang Pham ; Van Thanh Ta
Journal of Medical Research 2008;58(5):7-12
Background: Hemophilia A is a genetic bleeding disorder that results from a deficiency in factor VIII. The prevalence of Hemophilia in Vietnam is rather high (2/34830 people) and Vietnam has high usage demand for factor VIII in the treatment and prevention of the disease. Therefore, it is necessary to study and produce recombinant blood \u2013 coagulation factor WIII. Objective: To clone successfully A1A2 and A3C2 gen fragment encoding factor VIII. Subject and Method: Amplify A1A2 and A3C2 gene fragments by PCR from human cDNA. PCR products were ligated into cloning vector pQE \u2013 30UA. Recombinant plasmids were transformed into E.coli DH5 alpha host strain. Inserted A1A2 and A3C2 gene fragments were checked by PCR and restriction enzymes. Result: Successfully amplifying functional gene fragments encoding factor VIII using specific primers. Conclusion: Obtaining pQE \u2013 30UA vector carrying A1A2 and A3C2 fragments encoding factor VIII. This is the premise result for the next studies on synthesis of recombinant factor WIII and application of genetic therapy.
Hemophilia
;
Blood \u2013 coagulation factor VIII
2.Penicillium vietnamense sp. nov., the First Novel Marine Fungi Species Described from Vietnam with a Unique Conidiophore Structure and Molecular Phylogeny of Penicillium Section Charlesia
Van Duy NGUYEN ; Thu Thuy PHAM
Mycobiology 2022;50(3):155-165
Penicillium vietnamense sp. nov. was isolated from Nha Trang Bay, Vietnam in June 2017. It is phylogenetically distinct from the sister species of Penicillium section Charlesia series Indica based on multi-locus sequence typing results using internal transcribed spacer, large subunit ribosomal RNA, β-tubulin, calmodulin, and RNA polymerase II second largest subunit regions. It showed strong growth on Czapek yeast autolysate agar at 37 C, a strong acid production on Creatine sucrose agar, and produced short stipes, small vesicles, and subglobose to globose conidia delicately roughened with very short ridges. As the first novel marine fungi species described from Vietnam and discovered in a unique environment, the data could be significant for understanding the taxonomy and geographical distribution of marine fungi in tropical coastal systems such as Vietnam.
3.Biodiversity and Enzyme Activity of Marine Fungi with 28 New Records from the Tropical Coastal Ecosystems in Vietnam
Thu Thuy PHAM ; Khuong V. DINH ; Van Duy NGUYEN
Mycobiology 2021;49(6):559-581
The coastal marine ecosystems of Vietnam are one of the global biodiversity hotspots, but the biodiversity of marine fungi is not well known. To fill this major gap of knowledge, we assessed the genetic diversity (ITS sequence) of 75 fungal strains isolated from 11 surface coastal marine and deeper waters in Nha Trang Bay and Van Phong Bay using a culturedependent approach and 5 OTUs (Operational Taxonomic Units) of fungi in three representative sampling sites using next-generation sequencing. The results from both approaches shared similar fungal taxonomy to the most abundant phylum (Ascomycota), genera (Candida and Aspergillus) and species (Candida blankii) but were different at less common taxa. Culturable fungal strains in this study belong to 3 phyla, 5 subdivisions, 7 classes, 12 orders, 17 families, 22 genera and at least 40 species, of which 29 species have been identified and several species are likely novel. Among identified species, 12 and 28 are new records in global and Vietnamese marine areas, respectively. The analysis of enzyme activity and the checklist of trophic mode and guild assignment provided valuable additional biological information and suggested the ecological function of planktonic fungi in the marine food web. This is the largest dataset of marine fungal biodiversity on morphology, phylogeny and enzyme activity in the tropical coastal ecosystems of Vietnam and Southeast Asia. Biogeographic aspects, ecological factors and human impact may structure mycoplankton communities in such aquatic habitats.
4.Exposure to Extremely Low Frequency Magnetic Fields Induces Fos-Related Antigen-Immunoreactivity Via Activation of Dopaminergic D1 Receptor.
Eun Joo SHIN ; Xuan Khanh NGUYEN ; Thuy Ty NGUYEN ; Diem Thu PHAM ; Hyoung Chun KIM
Experimental Neurobiology 2011;20(3):130-136
We previously demonstrated that repeated exposure to extremely low frequency magnetic fields (ELF-MF) increases locomotor activity via stimulation of dopaminergic D1 receptor (J. Pharmacol. Sci., 2007;105:367-371). Since it has been demonstrated that activator protein-1 (AP-1) transcription factors, especially 35-kDa fos-related antigen (FRA), play a key role in the neuronal and behavioral adaptation in response to various stimuli, we examined whether repeated ELF-MF exposure induces FRA-immunoreactivity (FRA-IR) in the striatum and nucleus accumbens (striatal complex) of the mice. Repeated exposure to ELF-MF (0.3 or 2.4 mT, 1 h/day, for consecutive fourteen days) significantly induced hyperlocomotor activity and FRA-IR in the striatal complex in a field intensity-dependent manner. ELF-MF-induced FRA-IR lasted for at least 1 year, while locomotor activity returned near control level 3 months after the final exposure to ELF-MF. Pretreatment with SCH23390, a dopaminergic D1 receptor antagonist, but not with sulpiride, a dopaminergic D2 receptor antagonist, significantly attenuated hyperlocomotor activity and FRA-IR induced by ELF-MF. Our results suggest that repeated exposure to ELF-MF leads to prolonged locomotor stimulation and long-term expression of FRA in the striatal complex of the mice via stimulation of dopaminergic D1 receptor.
Animals
;
Benzazepines
;
Magnetic Fields
;
Magnetics
;
Magnets
;
Mice
;
Motor Activity
;
Neurons
;
Nucleus Accumbens
;
Sulpiride
;
Transcription Factor AP-1
;
Transcription Factors
5.Sexual awareness and cognitive social capital among high school students: a cross-sectional study in rural Vietnam
Kaori WATANABE ; Yumiko TOTSU ; Tran Thuy DUONG ; Pham Van TRUONG ; Phuong Thi Thu Huong
Journal of Rural Medicine 2020;15(4):132-138
Objective: Since the late 1980s, Vietnam has seen numerous social changes, likely leading to changes in adolescent sexual awareness. Adolescents are currently exposed to a plethora of sexual information without adequate sex education and knowledge. Globally, researchers have identified sexual knowledge and self-esteem as determinants of adolescent sexual awareness and behavior, but little is known about the role of social capital, especially in rural areas. This study aimed to clarify the relationship between sexual awareness and cognitive social capital among high school students in rural Vietnam.Materials and Methods: We conducted a questionnaire-based survey assessing sexual knowledge, sexual awareness, perceptions of peers’ sexual experience, structural and cognitive social capital, and self-esteem (Rosenberg Self-Esteem Scale) in March 2017 among 1,583 11th graders at four public high schools in Hai Duong Province, Vietnam.Results: The final sample comprised 1,517 students (95.8% of total responses): 609 boys (40.1%) and 908 girls (59.9%). Multiple logistic regression analysis was performed with intolerance toward premarital sex as the dependent variable. In the first model, the independent variables were self-esteem, knowledge of proper timing for condom use, and perception that many peers are sexually experienced. The second model added an indicator of cognitive social capital. In the first model, self-esteem, knowledge of proper timing for condom use, and perception that many peers are sexually experienced were all significantly associated with intolerance toward premarital sex for both boys and girls. In the second model, for both boys and girls, only cognitive social capital was significantly associated with intolerance toward premarital sex.Conclusion: The results of this study regarding the effect of social capital in rural Vietnam are consistent with previous findings in urban areas. Social capital should be emphasized in efforts to improve sexual awareness and, in turn, sexual and reproductive health among adolescents in rural areas.
6.Impact of long COVID-19 on posttraumatic stress disorderas modified by health literacy: an observational study inVietnam
Han Thi VO ; Tien Duc DAO ; Tuyen Van DUONG ; Tan Thanh NGUYEN ; Binh Nhu DO ; Tinh Xuan DO ; Khue Minh PHAM ; Vinh Hai VU ; Linh Van PHAM ; Lien Thi Hong NGUYEN ; Lan Thi Huong LE ; Hoang Cong NGUYEN ; Nga Hoang DANG ; Trung Huu NGUYEN ; Anh The NGUYEN ; Hoan Van NGUYEN ; Phuoc Ba NGUYEN ; Hoai Thi Thanh NGUYEN ; Thu Thi Minh PHAM ; Thuy Thi LE ; Thao Thi Phuong NGUYEN ; Cuong Quoc TRAN ; Kien Trung NGUYEN
Osong Public Health and Research Perspectives 2024;15(1):33-44
Objectives:
The prevalence of posttraumatic stress disorder (PTSD) has increased, particularly among individuals who have recovered from coronavirus disease 2019 (COVID-19) infection. Health literacy is considered a “social vaccine” that helps people respond effectively to the pandemic. We aimed to investigate the association between long COVID-19 and PTSD, and to examine the modifying role of health literacy in this association.
Methods:
A cross-sectional study was conducted at 18 hospitals and health centers in Vietnamfrom December 2021 to October 2022. We recruited 4,463 individuals who had recovered from COVID-19 infection for at least 4 weeks. Participants provided information about their sociodemographics, clinical parameters, health-related behaviors, health literacy (usingthe 12-item short-form health literacy scale), long COVID-19 symptoms and PTSD (Impact Event Scale-Revised score of 33 or higher). Logistic regression models were used to examine associations and interactions.
Results:
Out of the study sample, 55.9% had long COVID-19 symptoms, and 49.6% had PTSD.Individuals with long COVID-19 symptoms had a higher likelihood of PTSD (odds ratio [OR], 1.86; 95% confidence interval [CI], 1.63–2.12; p < 0.001). Higher health literacy was associated with a lower likelihood of PTSD (OR, 0.98; 95% CI, 0.97–0.99; p = 0.001). Compared to those without long COVID-19 symptoms and the lowest health literacy score, those with long COVID-19 symptoms and a 1-point health literacy increment had a 3% lower likelihood of PTSD (OR, 0.97; 95% CI, 0.96–0.99; p = 0.001).
Conclusion
Health literacy was found to be a protective factor against PTSD and modified the negative impact of long COVID-19 symptoms on PTSD.
7.Virological characteristics of cases of COVID-19 in northern Viet Nam, January–May 2020
Hang Khanh Le Nguyen ; Son Vu Nguyen ; Phuong Mai Vu Hoang ; Thanh Thi Le ; Huong thi Thu Tran ; Long Hai Pham Nguyen ; Thai Quang Pham ; Thuy Thanh Nguyen ; Anh Duc Dang ; Anh Phuong Nguyen ; Mai thi Quynh Le
Western Pacific Surveillance and Response 2021;12(4):65-70
Background:
Viet Nam confirmed its first case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on 23 January 2020 among travellers from Wuhan, China, and experienced several clusters of community transmission until September. Viet Nam implemented an aggressive testing, isolation, contact tracing and quarantine strategy in response to all laboratory-confirmed cases. We report the results of SARS-CoV-2 testing during the first half of 2020 in northern Viet Nam.
Methods:
Between January and May 2020, 15 650 upper respiratory tract specimens were collected from 14 470 suspected cases and contacts in northern Viet Nam. All were tested for SARS-CoV-2 by real-time RT-PCR. Individuals with positive specimens were tested every three days until two tests were negative. Positive specimens from 81 individuals were cultured.
Results:
Among 14 470 tested individuals, 158 (1.1%) cases of SARS-CoV-2 infection were confirmed; 89 were imported and 69 were associated with community transmission. Most patients (122, 77%) had negative results after two tests, while 11 and 4 still tested positive when sampled a third and fourth time, respectively. SARS-CoV-2 was isolated from 29 of 81 specimens (36%) with a cycle threshold (Ct) value <30. Seven patients who tested positive again after testing negative had Ct values >30 and negative cultures.
Conclusion
Early, widespread testing for SARS-CoV-2 in northern Viet Nam identified very few cases, which, when combined with other aggressive strategies, may have dramatically contained the epidemic. We observed rapid viral clearance and very few positive results after clearance. Large-scale molecular diagnostic testing is a critical part of early detection and containment of COVID-19 in Viet Nam and will remain necessary until vaccination is widely implemented.
8.Comparing multiplex and multiplex real-time polymerase chain reaction with traditional blood culture in bacterial detection among patients with septicemia
Loan Thi Nguyen ; Linh Trong Nguyen ; Trang Thu Nguyen ; Hien Minh Nguyen ; Thuy Thi Pham ; Huyen Thi La
Malaysian Journal of Microbiology 2022;18(3):242-250
Aims:
This study was aimed to test the specificity of primers and probes with target genes by using multiplex PCR and multiplex real-time PCR methods. These methods were compared with traditional blood culture methods in detecting five bacteria causing sepsis, including Acinetorbacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus.
Methodology and results:
A total of 587 blood samples from patients diagnosed with sepsis and septic shock were collected at Thanh Nhan Hospital, Hanoi, Vietnam. Each sample was divided into three parts for bacterial culture, multiplex PCR and multiplex real-time PCR to detect the similarity of the two PCR methods with the bacterial culture method. Conditions in multiplex PCR and multiplex real-time PCR were optimized to ensure the successful amplification of target genes. Results showed that the primers and probes were tested completely specific to the target genes and using multiplex PCR and multiplex real-time PCR techniques could detect five pathogens causing sepsis, including A. baumannii, K. pneumoniae, P. aeruginosa, E. coli and S. aureus.
Conclusion, significance and impact of study
Both multiplex PCR and multiplex real-time PCR methods have high similarities with the culture method, showing potential in the application of bacteria detection in sepsis.
Multiplex Polymerase Chain Reaction
;
Sepsis--microbiology
9.Isolation and toxicity of Xanthomonas oryzae pv. oryzae in rice and a collection of phages against the pathogen
Ngoc Quynh Anh Pham ; Vo Thanh Phuc ; Pham Do Tra My ; Le Thi My Duyen ; To Hue Ngoc ; Nguyen Minh Thien ; Nguyen Hai Duong ; Le Thi Thuy Tien ; Le Phi Nga ; Hoang Anh Hoang
Malaysian Journal of Microbiology 2024;20(no.1):15-23
Aims:
The objective of the study was to isolate bacteriophages and conduct a comprehensive analysis of their potential against Xanthomonas oryzae pv. oryzae (Xoo) strains in the Mekong Delta, Vietnam.
Methodology and results:
Twelve Xoo strains were isolated from rice fields located in the Mekong Delta, Vietnam. Among these strains, three strains Xoo L019, L020 and L024, showed the highest disease index of bacterial blight. Four
phages specific to Xoo were isolated from soil, water and leaf samples, and their morphologies were determined. In a test against 12 Xoo strains, phage L541, MLA23 or W41 could infect 10 of the 12 Xoo strains, while phage LBH01 could infect 8 of the 12 Xoo strains. The stability of the phages to pH, organic solvents, UV-A and UV-B was also evaluated.
Conclusion, significance and impact of study
The initial characterization of the phages indicates their potential as biocontrol agents against bacterial blight in rice. The study is one of the very first studies about Xoo phages in rice in Vietnam.