GHI NHẬN ĐẦU TIÊN VỀ ĐỘC TÍNH CỦA LOÀI VI KHUẨN LAM PLANKTOHRIX RUBESCENS PHÂN LẬP TỪ AO NUÔI CÁ TỈNH SÓC TRĂNG

Cyanobacteria and their toxicity are of environmental quality and ecological health concerns. This study aimed to determine the toxicity of the cyanobacterium Planktothrix rubescens from Vietnam. The cyanobaccterial samples from a fish pond in Soc Trang province were collected and brought to the laboratory for morphological species indentification and isolation for culture. The extracts of the cyanobacterium, P. rubescens, were used for microcystins characterization and toxicity testing on a micro-crustacean, Daphnia magna. The results contributed the first photos and morphological description on the cyanobacterium P. rubescens from Vietnam. The Enzyme Linked Immunoabsorbent Assay (ELISA) analysis indicated that all five strains of P. rubescens could produce microcystins at the concentrations of 0.06-0.42 µg/g dried weight. The chronic exposure of D. magna to the extract of P. rubescens, strain S1, revealed that the survival of the animal was strongly reduced. The toxicity of the extract to D. magna showed that there should be toxic sencondary metabolites other than microcystins in the extract. This study contributed the scientific information on the biodiversity and toxicity of cyanobacteria from Vietnam.Vi khuẩn lam và độc tính của nó là một trong những mối quan ngại liên quan đến chất lượng môi trường và sức khỏe sinh thái. Nghiên cứu này nhằm mục tiêu xác định độc tính của loài vi khuẩn lam Planktothrix rubescens có nguồn gốc Việt Nam. Mẫu vi khuẩn lam trong ao nuôi cá ở tỉnh Sóc Trăng được thu và mang về phòng thí nghiệm phục vụ việc định danh trên cơ sở hình thái học và phân lập để nuôi lấy sinh khối. Dịch chiết của loài P. rubescens được dùng để phân tích độc tố microcystins và dùng để thử nghiệm độc tính trên loài vi giáp xác Daphnia magna. Kết quả nghiên cứu đã đóng góp hình ảnh và mô tả hình thái đầu tiên cho loài vi khuẩn lam P. rubescens có nguồn gốc Việt Nam. Phân tích bằng ELISA (Enzyme Linked Immunoabsorbent Assay) đã cho thấy cả 5 chủng thuộc loài P. rubescens đều có thể 3 sản sinh độc tố microcystins với nồng độ từ 0,06 – 0,42 µg/g trọng lượng khô. Phơi nhiễm mãn tính D. magna với dịch chiết của P. rubescens, chủng S1, được quan sát và sức sống của sinh vật bị suy giảm đáng kể. Độc tính của dịch chiết đối với D. magna cho thấy trong dịch chiết ắt hẳn có chứa hợp chất thứ cấp khác có độc đối với vi giáp xác. Nghiên cứu này đóng góp thêm thông tin khoa học về đa dạng sinh học và độc học sinh thái của VKL có nguồn gốc Việt Na

Selective breeding of saline-tolerant striped catfish (Pangasianodon hypophthalmus) for sustainable catfish farming in climate vulnerable Mekong Delta, Vietnam

peer reviewedStriped catfish (Pangasianodon hypophthalmus), a freshwater species cultured mainly in the Mekong Delta region in Southern Vietnam, is facing a significant challenge due to salinity intrusion as a result of climatic changes. Given these evolving environmental conditions, selecting new strains with a higher salinity tolerance could make production of striped catfish economically feasible in brackish environments. In this study, we carried out a selection program aimed at developing a striped catfish strain able to survive and grow fast in a saline environment. To implement the selection program, we first collected males and females from different provinces in the Mekong delta. We next performed a factorial cross of these breeders to produce half- and full-sib families. When fish reached fry stage (47 dph), we put them in a saline environment (10 ppt) and subsequently kept 50 % of the fastest-growing fish after 143 days post hatching (dph). We repeated this mass selection procedure after 237 dph and 340 dph. We maintained in parallel a randomly selected group in saline conditions and a group of fish reared in freshwater to serve as controls. After crossing the selected individuals, we performed several tests on the next generation of fish to evaluate the effectiveness of selection after one generation in saline conditions. Average direct responses to selection were 18.0 % for growth and 11.4 % for survival rate after one generation of selection. We estimated a moderate realized heritability (0.29) for body weight. The genetic gains obtained in our study for body weight and survival rate after one generation of selection under saline conditions suggest that selection can be effective to improve ability of striped catfish to cope with saline stress. We conclude that our selection program has succeeded in developing a productive strain of striped catfish with better tolerance to salinity. © 2022 The Author

HierarchyNet : learning to summarize source code with heterogeneous representations

Code representation is important to machine learning models in the code-related applications. Existing code summarization approaches primarily leverage Abstract Syntax Trees (ASTs) and sequential information from source code to generate code summaries while often overlooking the critical consideration of the interplay of dependencies among code elements and code hierarchy. However, effective summarization necessitates a holistic analysis of code snippets from three distinct aspects: lexical, syntactic, and semantic information. In this paper, we propose a novel code summarization approach utilizing Heterogeneous Code Representations (HCRs) and our specially designed HierarchyNet. HCRs adeptly capture essential code features at lexical, syntactic, and semantic levels within a hierarchical structure. HierarchyNet processes each layer of the HCR separately, employing a Heterogeneous Graph Transformer, a Tree-based CNN, and a Transformer Encoder. In addition, HierarchyNet demonstrates superior performance compared to fine-tuned pre-trained models, including CodeT5, and CodeBERT, as well as large language models that employ zero/few-shot settings, such as CodeLlama, StarCoder, and CodeGen. Implementation details can be found at https://github.com/FSoft-AI4Code/HierarchyNet

Multivalvular involvement associated with Libman-Sacks endocarditis detected by multimodality imaging: A case report

Libman-Sacks endocarditis accounts for 6–11 percent of systemic lupus erythematosus patients and is associated with varying degrees of valvular dysfunction, increased risk for stroke and transient ischemic attacks, and increased mortality. In previous studies, left-sided valvular Libman-Sacks vegetations were more frequently detected than right sided vegetations; reported cases of bilateral involvement is very rare. A comprehensive clinical assessment and the multimodality imaging is of utmost importance in the management of systemic lupus erythematosus. In this case report, we describe a 31-year-old female patient with uncontrolled systemic lupus erythematosus initially presented with gastrointestinal symptoms but eventually had a vegetation-like structure on the posterior leaflet of the mitral valve which was revealed during routine echocardiography. Two-dimensional/three-dimensional transthoracic and transesophageal echocardiography, cardiac magnetic resonance, and cardiac computed tomography further characterized the mitral valve vegetation and revealed an additional vegetation of the pulmonary valve. Echocardiography remains the cornerstone for the detection of Libman-Sacks vegetations. Cardiac MRI and cardiac CT are useful in characterizing lesion size and effects and may prove particularly helpful in the assessment of right-sided or multivalvular endocarditis. The presence of focal brain lesions on brain MRI prompted antithrombotic therapy

Improvement in neoantigen prediction via integration of RNA sequencing data for variant calling

IntroductionNeoantigen-based immunotherapy has emerged as a promising strategy for improving the life expectancy of cancer patients. This therapeutic approach heavily relies on accurate identification of cancer mutations using DNA sequencing (DNAseq) data. However, current workflows tend to provide a large number of neoantigen candidates, of which only a limited number elicit efficient and immunogenic T-cell responses suitable for downstream clinical evaluation. To overcome this limitation and increase the number of high-quality immunogenic neoantigens, we propose integrating RNA sequencing (RNAseq) data into the mutation identification step in the neoantigen prediction workflow.MethodsIn this study, we characterize the mutation profiles identified from DNAseq and/or RNAseq data in tumor tissues of 25 patients with colorectal cancer (CRC). Immunogenicity was then validated by ELISpot assay using long synthesis peptides (sLP).ResultsWe detected only 22.4% of variants shared between the two methods. In contrast, RNAseq-derived variants displayed unique features of affinity and immunogenicity. We further established that neoantigen candidates identified by RNAseq data significantly increased the number of highly immunogenic neoantigens (confirmed by ELISpot) that would otherwise be overlooked if relying solely on DNAseq data.DiscussionThis integrative approach holds great potential for improving the selection of neoantigens for personalized cancer immunotherapy, ultimately leading to enhanced treatment outcomes and improved survival rates for cancer patients

Expansion of KPC-producing Enterobacterales in four large hospitals in Hanoi, Vietnam

Objectives : The incidence of carbapenem resistance among nosocomial Gram-negative bacteria in Vietnam is high and increasing, including among Enterobacterales. In this study, we assessed the presence of one of the main carbapenemase genes, blaKPC, among carbapenem-resistant Enterobacterales (CRE) from four large hospitals in Hanoi, Vietnam, between 2010 and 2015, and described their key molecular characteristics. Methods : KPC-producing Enterobacterales were detected using conventional PCR and were further analysed using S1 nuclease pulsed-field gel electrophoresis (S1-PFGE), Southern blotting and whole-genome sequencing (WGS) for sequence typing and genetic characterisation. Results : blaKPC genes were detected in 122 (20.4%) of 599 CRE isolates. blaKPC-carrying plasmids were diverse in size. Klebsiella pneumoniae harbouring blaKPC genes belonged to ST15 and ST11, whereas KPC-producing Escherichia coli showed more diverse sequence types including ST3580, ST448, ST709 and ST405. Genotypic relationships supported the hypothesis of circulation of a population of ‘resident’ resistant bacteria in one hospital through the years and of transmission among these hospitals via patient transfer. WGS results revealed co-carriage of several other antimicrobial resistance genes and three different genetic contexts of blaKPC-2. Among these, the combination of ISEcp1–blaCTX-M and ISKpn27–blaKPC–ΔISKpn6 on the same plasmid is reported for the first time. Conclusion : We describe the dissemination of blaKPC-expressing Enterobacterales in four large hospitals in Hanoi, Vietnam, since 2010, which may have started earlier, along with their resistance patterns, sequence types, genotypic relationship, plasmid sizes and genetic context, thereby contributing to the overall picture of the antimicrobial resistance situation in Enterobacterales in Vietnam

Ecological and human health risk assessments of cyanotoxins and heavy metals in a drinking water supply reservoir

Human beings are frequently exposed to a mixture of chemical pollutants through the ingestion of contaminated drinking water. The present study aimed to assess the ecological and human health risks associated with the contamination of cyanotoxins and heavy metals in a drinking water supply reservoir, the Tri An Reservoir (TAR), in Vietnam. Results demonstrated that the concentrations of individual heavy metals varied in the following order: iron (Fe) > lead (Pb) > arsenic (As) > zinc (Zn). Although the ecological potential risk of heavy metals was low during the study period, the concentration of Fe sometimes exceeded the Vietnamese standard for drinking water. Toxic cyanobacteria and microcystins (MCs) frequently occurred in the TAR with the highest density of 198.7 × 103 cells/mL and 7.8 μg/L, respectively, indicating a high risk of health impacts to humans. The results of the study indicate that exposure to heavy metals does not pose any non-carcinogenic health risks for both adults and children. However, the contamination of MCs in the surface water posed a serious disease enhancement to both adults and children through direct ingestion and dermal absorption. HIGHLIGHTS The ecological and human health risks associated with the contamination of cyanotoxins and heavy metals were investigated.; Water was contaminated with cyanotoxins and iron.; The potential risks of heavy metals were low, but the concentration of cyanotoxins indicated a high risk to human health.; This study highlights the ecological and human risks from exposure to mixtures of pollutants.

A new species of Psydrax (Vanguerieae, Rubiaceae) from the Gia Lai Plateau, southern Vietnam

Volume: 149Start Page: 99-10

Knowledge and practice on prevention of mosquito-borne diseases in livestock-keeping and non-livestock-keeping communities in Hanoi city, Vietnam: A mixed-method study

Mosquito-borne diseases (MBDs) are causing high morbidity and mortality for humans. Urban livestock keeping is still common in cities around the world. The animals may serve as reservoirs for zoonotic MBDs, which increase the risks for humans. Here we assess the knowledge and practices related to MBDs in households with livestock and without livestock and explore the perceptions of the health care sector about MBDs and livestock keeping in Hanoi city of Vietnam in a cross-sectional study. A quantitative survey was conducted including 513 households with and without livestock-keeping in six districts and complemented with qualitative surveys with four health staff from Hanoi Center of Disease Control and three district health centers. The quantitative survey indicated that the participants possessed basic knowledge on MBDs with an average score of 18.3 out of 35, of which non-livestock-keeping households had a better knowledge than households keeping livestock (p<0.05). Both household categories had low score, 3.5 out of 11, regarding preventive practices against MBDs. The negative binomial model showed that occupation and location of living were factors associated to the knowledge on MBDs. Farmers were likely to have better preventive practices as compared to office workers (p<0.05). Those who had better knowledge also had more adequate preventive practices against MBDs (p<0.001). The qualitative survey revealed that livestock keeping was determined as increasing risks of MBDs due to the increase of mosquito population. It is recommended that community campaigns to raise the awareness and change behavior on MBDs should be organized based on collaboration between the health sector and the veterinary sector for households with and without livestock living in central urban and peri-urban areas. Further studies are needed to confirm the association between urban livestock keeping and potential increasing risks of MBDs such as dengue and Japanese encephalitis