Caractérisation de certains gènes polycétones synthases chez Aspergillus Ochraceus NRRL 3174 producteur d'ochratoxine A et d'acide pénicillique

Le champignon Aspergillus ochraceus est connu comme producteur de plusieurs polycétones dont les mycotoxines ochratoxines et acide pénicillique. L'étude de la diversité des gènes de polycétones synthases (PKS) chez Aspergillus ochraceus NRRL 3174 a été abordée en utilisant quatre couples d'amorces dégénérées dessinés pour cibler le domaine ketosynthase (3) et le domaine acyltransferase (1). 10 PKS différentes de type I ont été identifiées. Elles sont distribuées dans les trois groupes principaux de PKS : PKS réduite, partiellement réduite et non réduite. Le gène AoLC35-12 est responsable de la production d'ochratoxine A chez A. ochraceus. Le gène aomsas de type 6-methylsalicylique synthase intervient dans la biosynthèse d'acide pénicillique, de patuline, d'asperlactone, d'isoasperlactone, de melleine, d'hydroxymelleine et d'ochratoxine A. Ce gène a été totalement séquencé. Deux couples d'amorces spécifiques ont été synthétisés à partir du gène AoLC35-12. Avec le couple AoOTAL/AoOTAR, uniquement A. ochraceus est détecté par méthode PCR. Avec l'autre couple d'amorces, AoLC35-12L/AoLC35-12R, il est possible de détecter à la fois les producteurs d'ochratoxine A et les producteurs de citrinine. Des amorces spécifiques ont également été développées pour la détection rapide d'A. carbonarius, de P. verrucosum et de P. citrinum. ABSTRACT : Aspergillus ochraceus is known to produce many polyketides including ochratoxins and penicillic acid. The diversity of polyketide synthase (PKS) genes in A. ochraceus NRRL 3174 was investigated by using four degenerate primer pairs targeting ketosynthase domain (3) and acyltransferase domain (1). 10 different type I PKS were identified, and were classed into three main PKS groups: reduced, partially reduced and non reduced. AoLC35-12 gene was found to be involved in OTA biosynthesis. A PKS gene of 6-methylsalicyclic acid synthase type, aomsas, was found to be involved in the biosynthesis of penicillic acid, patulin, asperlactone, isoasperlactone, mellein, hydroxymellein, and ochratoxin A. This gene was completely sequenced. In order to detect ochratoxin A and citrinin producers by using PCR method, two specific primer pairs were generated from AoLC35-12 gene. AoOTAL/AoOTAR can detect only A. ochraceus while AoLC35-12L/AoLC35-12R can detect either ochratoxin A or citrinin producer fungi. Specific primers were also developed to detect A. carbonarius, P. verrucosum and P. citrinum

Cloning and characterization of novel methylsalicylic acid synthase gene involved in the biosynthesis of isoasperlactone and asperlactone in Aspergillus westerdijkiae

Aspergillus westerdijkiae is the main producer of several biologically active polyketide metabolites including isoasperlactone and asperlactone. A 5298 bp polyketide synthase gene ‘‘aomsas” has been cloned in Aspergillus westerdijkiae by using gene walking approach and RACE-PCR. The predicted amino acid sequence of aomsas shows an identity of 40–56% with different methylsalicylic acid synthase genes found in Byssochlamys nivea, P. patulum, A. terreus and Streptomyces viridochromogenes. Based on the reverse transcription PCR and kinetic secondary metabolites production studies, aomsas expression was found to be associated with the biosynthesis of isoasperlactone and asperlactone. Moreover an aomsas knockout mutant ‘‘aoDmsas” of A. westerdijkiae, not only lost the capacity to produce isoasperlactone and asperlactone,but also 6-methylsalicylic acid. The genetically complemented mutant ao+msas restored the biosynthesis of all the missing metabolites. Chemical complementation through the addition of 6-methylsalicylic acid, aspyrone and diepoxide to growing culture of aoDmsas mutant revealed that these compounds play intermediate roles in the biosynthesis of asperlactone and isoasperlactone

Extended state observer based load frequency controller for three area interconnected power system

In this paper, we develop a new extended state variable observer based LFC scheme for three-area interconnected power systems. The extended state observerbased load frequency controllers are developed which utilize disturbance estimation techniques. The propose control approach assures that the fluctuating things of the load frequencies reaches to a safer range and the load frequencies can also be made at a very minimal not to have an effect on power quality and power flow in multi-area interconnected power system. The results of the simulations using MATLAB/SIMULINK done did not only address that the proposed newly control method works effectively but also change powerfully the parameter variations of the interconnected areas of the power system. Especially, it works very well to limit disturbances impact on interconnected areas in the system. Therefore, the performance of interconnected power system under different multi-conditions is simulated with the new control method to demonstrate the feasibility of the system

Impact of Strategic Management Accounting on Operating Performance: Research in Public Universities of Vietnam

Purpose: The study aims to evaluate the impact of strategic management accounting (SMA) on the operating performance of Vietnamese public universities in terms of autonomy, student size, and number of years of establishment.   Theoretical framework: The paper is based on the theory of strategic management accounting, including the use of strategic management accounting as well as the characteristics of organizations in general and universities in particular.   Design/Methodology/Approach: Survey data were collected from 142 accountants of 102 public higher education institutions, cleaned data, and used regression analysis by SPSS 22 software.   Findings: The results showed that with 07 factors of SMA stands for Strategic Application (AD), Strategic Planning (LKH), Strategic Management Accounting (KT), Financial Measures (TC), Non-Financial Measures (PTC), Reporting strategy (BC), and Strategic Management Decision Making (RQD), there are only 3 factors that have an impact on the performance of quality universities (Application of Strategy, Quality Management Accounting Techniques, and Financial Measures). Considering the control variable, only the degree of autonomy, and the number of students have a positive effect on the impact of quality management accounting information and the performance of universities.   Research, practical & social implications: The results contribute to additional evidence for managers to pay more attention to quality management accounting information, thereby improving the universites' operational performance. In addition, this study complements the literature review documents related to the content of SMA and the impact of using SMA on the performance of universities.   Originality/Value: The study provided an extension on the impact of SMA on the performance of universities as well as the mediating role of the control variable on the relationship between SMA and performance. Research results provide useful references for research on related issues

Spatiotemporal evolution of SARS-CoV-2 Alpha and Delta variants during large nationwide outbreak of COVID-19, Vietnam, 2021

We analyzed 1,303 SARS-CoV-2 whole-genome sequences from Vietnam, and found the Alpha and Delta variants were responsible for a large nationwide outbreak of COVID-19 in 2021. The Delta variant was confined to the AY.57 lineage and caused >1.7 million infections and >32,000 deaths. Viral transmission was strongly affected by nonpharmaceutical interventions

Caractérisation de certains gènes polycétones synthases chez Aspergillus Ochraceus NRRL 3174 producteur d'ochratoxine A et d'acide pénicillique

L'étude de la diversité des gènes de polycétones synthases (PKS) chez Aspergillus ochraceus NRRL 3174 a été abordée en utilisant quatre couples d'amorces dégénérées dessinés pour cibler le domaine ketosynthase (3) et le domaine acyltransferase (1). 10 PKS différentes de type I ont été identifiées. Elles sont distribuées dans les trois groupes principaux de PKS : PKS réduite, partiellement réduite et non réduite. Le gène AoLC35-12 est responsable de la production d'ochratoxine A chez A. ochraceus. Le gène aomsas intervient dans la biosynthèse d'acide pénicillique, de patuline, d'asperlactone, d'isoasperlactone, de melleine, d'hydroxymelleine et d'ochratoxine A. Ce gène a été totalement séquencé. Deux couples d'amorces spécifiques ont été synthétisés à partir du gène AoLC35-12. Avec le couple AoOTAL/AoOTAR, uniquement A. ochraceus est détecté par méthode PCR. Avec l'autre couple d'amorces, AoLC35-12L/AoLC35-12R, il est possible de détecter à la fois les producteurs d'ochratoxine A et les producteurs de citrinine. Des amorces spécifiques ont également été développées pour la détection rapide d'A. carbonarius, de P. verrucosum et de P. citrinum.TOULOUSE-ENSAT-Documentation (315552324) / SudocSudocFranceF

Routine Medical Check-Up and Self-Treatment Practices among Community-Dwelling Living in a Mountainous Area of Northern Vietnam

This study was conducted to evaluate the routine medical check-up and self-treatment behaviors of people living in a remote and mountainous setting in Northern Vietnam and identify their associations. A cross-sectional study was conducted on 175 people in August 2018 in Cao Son commune, Da Bac district, Hoa Binh. Information regarding routine medical check-ups and self-treatment behaviors was collected by using a structured questionnaire. Multivariate logistic regression was used to examine the associations. Results show that 24% of the mountainous people had routine medical check-ups in the last 12 months. The rate of self-treatment in the past three months was 33.7%. The number of chronic diseases (OR=1.5, 95% CI=1.0‐2.3), health information sources from radio/television (OR=3.3, 95% CI=1.2‐9.5), or social media (OR=24.8, 95% CI=1.2‐512.4) was related to routine medical check-up. People who did not have routine medical check-up were more likely to have self-treatment practice (OR=6.3, 95% CI=1.9‐21.1) than those who had a regular health check. Promoting health education and communication through mass media to raise people’s awareness about regular health check-ups is a promising way to improve people’s self-treatment status

An observational study of breakthrough SARS-CoV-2 Delta variant infections among vaccinated healthcare workers in Vietnam

Background Data on breakthrough SARS-CoV-2 Delta variant infections in vaccinated individuals are limited. Methods We studied breakthrough infections among Oxford-AstraZeneca vaccinated healthcare workers in an infectious diseases hospital in Vietnam. We collected demographic and clinical data alongside serial PCR testing, measurement of SARS-CoV-2 antibodies, and viral whole-genome sequencing. Findings Between 11th–25th June 2021 (7-8 weeks after the second dose), 69 staff tested positive for SARS-CoV-2. 62 participated in the study. Most were asymptomatic or mildly symptomatic and all recovered. Twenty-two complete-genome sequences were obtained; all were Delta variant and were phylogenetically distinct from contemporary viruses obtained from the community or from hospital patients admitted prior to the outbreak. Viral loads inferred from Ct values were 251 times higher than in cases infected with the original strain in March/April 2020. Median time from diagnosis to negative PCR was 21 days (range 8–33). Neutralizing antibodies (expressed as percentage of inhibition) measured after the second vaccine dose, or at diagnosis, were lower in cases than in uninfected, fully vaccinated controls (median (IQR): 69.4 (50.7-89.1) vs. 91.3 (79.6-94.9), p=0.005 and 59.4 (32.5-73.1) vs. 91.1 (77.3-94.2), p=0.043). There was no correlation between vaccine-induced neutralizing antibody levels and peak viral loads or the development of symptoms. Interpretation Breakthrough Delta variant infections following Oxford-AstraZeneca vaccination may cause asymptomatic or mild disease, but are associated with high viral loads, prolonged PCR positivity and low levels of vaccine-induced neutralizing antibodies. Epidemiological and sequence data suggested ongoing transmission had occurred between fully vaccinated individuals