1.Capsaicin-Induced Apoptosis of FaDu Human Pharyngeal Squamous Carcinoma Cells.
Thanh Do LE ; Dong Chun JIN ; Se Ra RHO ; Myung Su KIM ; Rina YU ; Hoon YOO
Yonsei Medical Journal 2012;53(4):834-841
PURPOSE: To investigate the anti-tumor effect of capsaicin on human pharyngeal squamous carcinoma cells (FaDu). MATERIALS AND METHODS: The expression of apoptosis/cell cycle-related proteins (or genes) was examined by reverse transcriptase-polymerase chain reaction, western blotting and ELISA methods, while the apoptotic cell population, cell morphology and DNA fragmentation levels were assessed using flow cytometry, fluorescence microscopy and agarose gel electrophoresis. RESULTS: Capsaicin was found to inhibit the growth and proliferation of FaDu cells in a dose- and time-dependent manner. Apoptotic cell death was confirmed by observing increases in nuclear condensation, nuclear DNA fragmentation and sub-G1 DNA content. The observed increase in cytosolic cytochrome c, activation of caspase 3 and PARP (p85) levels following capsaicin treatment indicated that the apoptotic response was mitochondrial pathway-dependent. Gene/protein expression analysis of Bcl-2, Bad and Bax further revealed decreased anti-apoptotic Bcl-2 protein and increased pro-apoptotic Bad/Bax expression. Furthermore, capsaicin suppressed the cell cycle progression at the G1/S phase in FaDu cells by decreasing the expression of the regulators of cyclin B1 and D1, as well as cyclin-dependent protein kinases cdk-1, cdk-2 and cdk-4. CONCLUSION: Our current data show that capsaicin induces apoptosis in FaDu cells and this response is associated with mitochondrial pathways, possibly by mediating cell cycle arrest at G1/S.
Apoptosis/drug effects
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Blotting, Western
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Capsaicin/*pharmacology
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Carcinoma, Squamous Cell/*metabolism
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Cell Cycle/drug effects
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Cell Line, Tumor
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Cell Proliferation/drug effects
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Enzyme-Linked Immunosorbent Assay
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Flow Cytometry
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Humans
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Microscopy, Fluorescence
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Pharyngeal Neoplasms/*metabolism
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Proto-Oncogene Proteins c-bcl-2/genetics/metabolism
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Reverse Transcriptase Polymerase Chain Reaction
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bcl-2-Associated X Protein/genetics/metabolism
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bcl-Associated Death Protein/genetics/metabolism
2.Surveillance for Vibrio cholerae 01 and vibriophages in surface water - the factors for prediction of cholera outbreaks
Tu Dong Nguyen ; Cuong Tuan Ngo ; Thu Hoai Nguyen ; Huong Thanh Le ; Minh Binh Nguyen ; Ninh Kim Do ; Diu Van Phan ; Thuy Minh Tran
Journal of Preventive Medicine 2008;96(4):13-18
Background: In countries that cholera outbreaks commonly occurs, surveillance of surface water is important to control the epidemics. Kappa phage (K139) of Vibrio cholerae is related to epidemic El Tor and O139 strains in various countries. Objectives: To study the relationships between V. cholerae 01 and vibriophages in surface water in Thai Binh and Hai Phong city and to determine the predictors of cholera outbreaks. Subjects and method: Total of 82 water samples were collected by shrimp swab method in Hai Phong and Thai Binh in June and September 2007, where cholera outbreaks occurred. The enriched culture method and direct peR were applied to define the relationships between vibriophages and V. cholerae 01 in surface water. Results: The rates of detecting kappa junction with chromosomes of V. cholerae 01 in Hai Phong and Thai Binh were 10% and 15% in June 2007, 35% and 41% in September 2007. The rates of detecting vibriophages in Hai Phong and Thai Binh were 15% and 15% in June 2007, 25% and 36% in September 2007. The rates of Fs1 and Fs2 detected by PCR method were 70% and 100% in Hai Phong at June and September 2007, and were 57% and 100% in Thai Binh at June and September 2007, respectively. V. cholerae 01, O139 weren\u2019t found in water samples. Conclusion: The presences of vibriophages (kappa phage and fs1 fs2) in surface water contaminated with V. cholerae 01 were dependent on the ability of the vibriophages to infect and lyse these bacteria. Vibriophages played a role in the transfer of cholera toxin and pathogenic factors. Surveillance by detecting V. cholerae 01 and vibriophages in surface water may be a feasible means of predicting outbreaks of cholera before a significant number of cases occur.
Vibrio cholerae 01
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vibriophages
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surface water
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cholera outbreaks
3.Identification of Trombiculid Chigger Mites Collected on Rodents from Southern Vietnam and Molecular Detection of Rickettsiaceae Pathogen
Minh Doan BINH ; Sinh Cao TRUONG ; Dong Le THANH ; Loi Cao BA ; Nam Le VAN ; Binh Do NHU
The Korean Journal of Parasitology 2020;58(4):445-450
Trombiculid “chigger” mites (Acari) are ectoparasites that feed blood on rodents and another animals. A crosssectional survey was conducted in 7 ecosystems of southern Vietnam from 2015 to 2016. Chigger mites were identified with morphological characteristics and assayed by polymerase chain reaction for detection of rickettsiaceae. Overall chigger infestation among rodents was 23.38%. The chigger index among infested rodents was 19.37 and a mean abundance of 4.61. A total of 2,770 chigger mites were identified belonging to 6 species, 3 genera, and 1 family, and pooled into 141 pools (10-20 chiggers per pool). Two pools (1.4%) of the chiggers were positive for Orientia tsutsugamushi. Ricketsia spp. was not detected in any pools of chiggers. Further studies are needed including a larger number and diverse hosts, and environmental factors to assess scrub typhus.
4.Identification of Phenolic Compounds from Vietnamese Artichoke (Cynara scolymus L.) Leaf and Their Antioxidant Activities
Anh Nguyet Thi NGUYEN ; Thanh Tuyen Thi VU ; Hong Tuoi Thi DO ; Thien Hai NGUYEN ; Huan Van LE ; Hong Khuyen Thi PHAM ; Phu Chi Hieu TRUONG ; Dong Phuong PHAM ; Manh Hung TRAN
Natural Product Sciences 2024;30(1):39-51
Artichoke (Cynara scolymus L.) is a perennial plant belonging to the Asteraceae family originating from the Mediterranean region. In Vietnam, there are some varieties of artichoke which are extensively cultivated and propagated in highland areas, however, there have been limited detailed scientific publications on the chemical composition and biological activity of artichoke grown in Vietnam. Therefore, this study provides a detailed description of the extraction, isolation, and structural determination of 20 natural secondary metabolites present in harvested artichoke. The antioxidant activity of the extract and the 9 isolated compounds are tested in 1,1-diphenyl-2-picrylhydrazyl radical scavenging and ex vivo malondialdehyde model. Among the selected compounds, 1-caffeoylquinic acid, 3-caffeoylquinic acid, chlorogenic acid, 4-caffeoylquinic acid, cynarin, 1,5-dicaffeoylquinic acid, 4,5-di-caffeoylquinic acid, cynaroside, and scolymoside exhibited strong radical scavenging activity with IC50 values ranging from 5.7 to 61.6 µM. In the malondialdehyde assay, 1,3-dicaffeoylquinic acid (or cynarin) showed the strongest activity with an IC50 value of 24.7 µM, followed by 1,5-di-caffeoylquinic acid (66.8 µM), and 4,5-di-caffeoylquinic acid (127.3 µM). This outcome contributes to establishing a database on the phytochemical and antioxidant activity of the Vietnamese artichoke.
5.Large-scale salmonella outbreak associated with banh mi, Viet Nam, 2024
Tinh Huu Ho ; Phuong Hoai Hoang ; Lam Vo Thi Ngoc ; Minh Nguyen Dinh ; Dong Do Thanh ; Viet Nguyen Dinh ; O Phan Van ; Phuong Nguyen Thi Lan ; Thanh Nguyen Quoc ; Nhan Ho The ; Nhan Le Dinh Trong ; Chinh Van Dang
Western Pacific Surveillance and Response 2024;15(3):36-42
Objective: To investigate the cause of a foodborne outbreak that occurred in Dong Nai province, Viet Nam, in 2024, and implement control measures.
Methods: An initial investigation was conducted to confirm the outbreak, which was followed by epidemiological and environmental investigations to find the plausible causative food item. Clinical specimens and food samples were tested to identify the pathogen.
Results: A total of 547 symptomatic cases were recorded, of whom two were in severe condition requiring extracorporeal membrane oxygenation and ventilation, one of whom died. Among 99 interviewed cases, the mean incubation time was 9 hours (range 2–24 hours), with the main symptoms being fever, abdominal pain, diarrhoea and vomiting. All patients had eaten banh mi from a local bakery. Salmonella spp. were identified in food samples and clinical specimens. The bakery halted production, and the outbreak ended after 1 week.
Discussion: All the patients were exposed to only one food in common, which facilitated the investigation process. This outbreak is a reminder to small retailers and take-away shops of the importance of food safety management in preventing similar future outbreaks. All food handlers must comply with food hygiene principles, especially in hot temperatures, which boosts bacterial growth.
6.Systematic sequencing of imported cases leads to detection of SARS-CoV-2 B.1.1.529 (Omicron) variant in central Viet Nam
Do Thai Hung ; Nguyen Bao Trieu ; Do Thi Thu Thuy ; Allison Olmsted ; Trinh Hoang Long ; Nguyen Duc Duy ; Huynh Kim Mai ; Bui Thi Thu Hien ; Nguyen Van Van ; Tran Van Kiem ; Vo Thi Thuy Trang ; Nguyen Truong Duy ; Ton That Thanh ; Huynh Van Dong ; Philip L Gould ; Matthew R Moore
Western Pacific Surveillance and Response 2022;13(4):82-85
As authorities braced for the arrival of the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), infrastructure investments and government directives prompted action in central Viet Nam to establish capacity for genomic surveillance sequencing. From 17 November 2021 to 7 January 2022, the Pasteur Institute in Nha Trang sequenced 162 specimens from 98 150 confirmed SARS-CoV-2 cases in the region collected from 8 November to 31 December 2021. Of these, all 127 domestic cases were identified as the B.1.617.2 (Delta) variant, whereas 92% (32/35) of imported cases were identified as the B.1.1.529 (Omicron) variant, all among international flight passengers. Patients were successfully isolated, enabling health-care workers to prepare for additional cases. Most (78%) of the 32 Omicron cases were fully vaccinated, suggesting continued importance of public health and social measures to control the spread of new variants.