We sampled nasal-pharyngeal throat swabs from 96,123 asymptomatic individuals at risk of SARS-CoV-2 infection, and generated 22,290 pools at collection, each containing samples from two to seven ...individuals. We detected SARS-CoV-2 in 24 pools, and confirmed the infection in 32 individuals after resampling and testing of 104 samples from positive pools. We completed the testing within 14 days. We would have required 64 days to complete the screening for the same number of individuals if we had based our testing strategy on individual testing. There was no difference in cycle threshold (Ct) values of pooled and individual samples. Thus, compared with individual sample testing, our approach did not compromise PCR sensitivity, but saved 77% of the resources. The present strategy might be applicable in settings, where there are shortages of reagents and the disease prevalence is low, but the demand for testing is high.
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In this work, we report 14 novel quinazoline derivatives as immune checkpoint inhibitors, IDO1 and PD-L1. The antitumor screening of synthesized compounds on ovarian cancer cells ...indicated that compound V-d and V-l showed the most activity with IC50 values of about 5 μM. Intriguingly, compound V-d emerges as a stand out, triggering cell death through caspase-dependent and caspase-independent manners. More importantly, V-d presents its ability to hinder tumor sphere formation and re-sensitized cisplatin-resistant A2780 cells to cisplatin treatment. These findings suggest that compound V-d emerges as a promising lead candidate for the future development of immuno anticancer agents.
Microbial fuel cells are one of the alternative methods that generate green, renewable sources of energy from wastewater. In this study, a new bio-electrochemical system called the sulfide-oxidizing ...fuel cell (SOFC) is developed for the simultaneous removal of sulfide/sulfide and electricity generation. To improve the application capacity of the SOFC, a system combining sulfate-reducing and sulfide-oxidizing processes for sulfate/sulfide removal and electricity generation was designed. Key factors influencing the sulfide-removal efficiency and electricity-generation capacity of the SOFC are the anolytes and catholytes. The sulfide produced from the sulfate-reducing process is thought to play the key role of an electron mediator (anolyte), which transfers electrons to the electrode to produce electricity. Sulfide can be removed in the anodic chamber of the SOFC when it is oxidized to the element sulfur (S°) through the biochemical reaction at the anode. The performance of wastewater treatment for sulfate/sulfide removal and electricity generation was evaluated by using different catholytes (dissolved oxygen in deionized water, a phosphate buffer, and ferricyanide). The results showed that the sulfate-removal efficiency is 92 ± 1.2% during a 95-day operation. A high sulfide-removal efficiency of 93.5 ± 1.2 and 83.7 ± 2% and power density of 18.5 ± 1.1 and 15.2 ± 1.2 mW/m2 were obtained with ferricyanide and phosphate buffers as the catholyte, respectively, which is about 2.6 and 2.1 times higher than dissolved oxygen being used as a catholyte, respectively. These results indicated that cathode electron acceptors have a direct effect on the performance of the treatment system. The sulfide-removal efficiency and power density of the phosphate buffer SOFC were only slightly less than the ferricyanide SOFC. Therefore, a phosphate buffer could serve as a low-cost and effective pH buffer for practical applications, especially for wastewater treatment. The results presented in this study clearly revealed that the integrated treatment system can be effectively applied for sulfate/sulfide removal and electricity generation simultaneously.
A wastewater treatment system has been established based on sulfate-reducing and sulfide—oxidizing processes for treating organic wastewater containing high sulfate/sulfide. The influence of ...COD/SO42− ratio and hydraulic retention time (HRT) on removal efficiencies of sulfate, COD, sulfide and electricity generation was investigated. The continuous operation of the treatment system was carried out for 63 days with the optimum COD/SO42− ratio and HRT. The result showed that the COD and sulfate removal efficiencies were stable, reaching 94.8 ± 0.6 and 93.0 ± 1.3% during the operation. A power density level of 18.0 ± 1.6 mW/m2 was obtained with a sulfide removal efficiency of 93.0 ± 1.2%. However, the sulfide removal efficiency and power density decreased gradually after 45 days. The results from scanning electron microscopy (SEM) with an energy dispersive X-ray (EDX) show that sulfur accumulated on the anode, which could explain the decline in sulfide oxidation and electricity generation. This study provides a promising treatment system to scale up for its actual applications in this type of wastewater.
Fermentation has been used for centuries to produce food in South-East Asia and some foods of this region are famous in the whole world. However, in the twenty first century, issues like food safety ...and quality must be addressed in a world changing from local business to globalization. In Western countries, the answer to these questions has been made through hygienisation, generalization of the use of starters, specialization of agriculture and use of long-distance transportation. This may have resulted in a loss in the taste and
of the products, in an extensive use of antibiotics and other chemicals and eventually, in a loss in the confidence of consumers to the products. The challenges awaiting fermentation in South-East Asia are thus to improve safety and quality in a sustainable system producing tasty and typical fermented products and valorising by-products. At the end of the "AsiFood Erasmus+ project" (www.asifood.org), the goal of this paper is to present and discuss these challenges as addressed by the Tropical Fermentation Network, a group of researchers from universities, research centers and companies in Asia and Europe. This paper presents current actions and prospects on hygienic, environmental, sensorial and nutritional qualities of traditional fermented food including screening of functional bacteria and starters, food safety strategies, research for new antimicrobial compounds, development of more sustainable fermentations and valorisation of by-products. A specificity of this network is also the multidisciplinary approach dealing with microbiology, food, chemical, sensorial, and genetic analyses, biotechnology, food supply chain, consumers and ethnology.
Rural farming communities in northern Vietnam do not routinely practice vaccination for influenza A viruses (IAV) for either humans or poultry, which enables us to study transmission intensity via ...seroepidemiology. Using samples from a longitudinal cohort of farming households, we determined the number of symptomatic and asymptomatic human infections for seasonal IAV and avian A/H9 over 2 years. As expected, we detected virologically confirmed acute cases of seasonal IAV in humans, as well as large numbers of subclinical seroconversions to A/H1pdm 55/265 (21 %), A/H3 95/265 (36 %) and A/H9 24/265 (9 %). Five of the A/H9 human seroconverters likely represented true infections rather than heterosubtypic immunity, because the individuals seroconverted solely to A/H9. Among co-located poultry, we found significantly higher seroprevalance for A/H5 compared to A/H9 in both chickens and ducks for northern study sites overall, 337/1105 (30.5 %) seropositive for A/H5 and 123/1105 (11.1 %) seropositive for A/H9.
Eco-friendly, active, non-toxic coatings have recently been considered as a feasible approach for enhancing the storability of post-harvest produce, which deal with global problem from environmental ...pollutions of chemical uses and petro-based plastics. In this interest, the present work is to the development of multifunctional coating films through blending gelatin, agarose, d-glucose, and Piper betle L. extract before being applied for preserving ‘Duong’ mandarin. As compared to single addition of agarose, the co-supplement of agarose and d-glucose was considered to be more efficient in revitalizing the mechanical strength and surface hydrophobicity of the neat gelatin, which highlighted a vital role of d-glucose in the polymeric network. Interestingly, gelatin/d-glucose/agarose formulated with Piper betle L. extract showed greater mechanical strength, flexibility, UV-shielding, solubility, antibacterial and antioxidant activities than gelatin/d-glucose/agarose coating films. Considerably, the antibacterial property of such active films/coatings was found to even better after being aged for 30 days at the room temperature (25 °C). Based on initial screening, the gelatin/agarose/d-glucose coating formulation included with 2 % (w/w) Piper betle L. extract presenting the best mechanical strength (2.46 MPa), flexibility (31.03 %), and antioxidant activity (IC50 = 37.45 μg/mL) along with the adequate tested bacterial inhibition, was applied for ready-to-eat mandarin preservation. The significant improvement in visual appearance and peel color was recorded for the mandarin coated with gelatin/agarose/d-glucose/Piper betle L. extract (2 %, w/w) after 17-d storage at 20 °C and 64 %RH, which exhibited the lowest mass loss and total soluble solids.
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•Multifunctional film was developed through blending gelatin, agarose, d-glucose and PBE.•Blended films possessed robust mechanical, UV-shielding, and antioxidant properties.•PBE provided strong antibacterial function to GAD film and this property was remained after being aged 30 d at 25 °C.•The coating could efficiently delay the ripening of ‘Duong’ mandarins for 17 d stored at the near-room temperature.
In Vietnam, a great number of toxic substances, including carcinogens and procarcinogens, from industrial and agricultural activities, food production, and healthcare services are daily released into ...the environment. In the present study, we report the development of novel yeast-based biosensor systems to determine both genotoxic carcinogens and procarcinogens by cotransformation with two plasmids. One plasmid is carrying human CPR and CYP (CYP3A4, CYP2B6, or CYP2D6) genes, while the other contains the RAD54-GFP reporter construct. The three resulting coexpression systems bearing both CPR-CYP and RAD54-GFP expression cassettes were designated as CYP3A4/CYP2B6/CYP2D6 + RAD54 systems, respectively and used to detect and evaluate the genotoxic potential of carcinogens and procarcinogens by selective activation and induction of both CPR-CYP and RAD54-GFP expression cassettes in response to DNA damage. Procarcinogens were shown to be predominantly, moderately or not bioactivated by one of the CYP enzymes and thus selectively detected by the specific coexpression system. Aflatoxin B1 and benzo(a)pyrene were predominantly detected by the CYP3A4 + RAD54 system, while N-nitrosodimethylamine only moderately activated the CYP2B6 + RAD54 reporter system and none of them was identified by the CYP2D6 + RAD54 system. In contrast, the genotoxic carcinogen, methyl methanesulfonate, was detected by all systems. Our yeast-reporter system can be performed in 384-well microplates to provide efficient genotoxicity testing to identify various carcinogenic compounds and reduce chemical consumption to about 53% as compared with existing 96-well genotoxicity bioassays. In association with a liquid handling robot, this platform enables rapid, cost-effective, and high-throughput screening of numerous analytes in a fully automated and continuous manner without the need for user interaction.
Houttuynia cordata Thunb. has long been widely used as a daily vegetable and traditional medicine. The flavonoid component of H. cordata has plenty of pharmacological effects, such as antibacterial, ...anti-inflammatory, and antioxidant. In this study, we applied the aqueous two-phase system (ATPS) combined with ultrasonic extraction for extracting H. cordata leaves.
We optimized the extraction process to improve the extraction efficiency of the two flavonoids, hyperin and quercitrin, by Surface Method Response - Central Composite Design (RSM-CCD). Next, we investigated the antibacterial ability of H. cordata ATPS extract from optimal conditions against two bacterial strains, Cutibacterium acnes and Staphylococcus epidermidis.
The results showed that using 10% (NH4)2SO4 and 35% ethanol for ATPS extraction resulted in the highest hyperin and quercitrin contents. From the RSM-CCD results, the optimal extraction conditions were determined to be ultrasonic extraction at 50 °C for 30 min, giving results consistent with the predicted model and obtaining hyperin and quercitrin contents at 1.5681 ± 0.0114 and 4.6225 ± 0.0327 mg/g, respectively.
Furthermore, ATPS extract has excellent antibacterial activity with a minimum inhibitory concentration (MIC) value of 250 μg/mL on both C. acnes and S. epidermidis. This MIC is significantly lower than the H. cordata ultrasound-assisted (UA) extract, with MICs of 1500.00 and 156.25 μg/mL on C. acnes and S. epidermidis, respectively. In addition, the results from the disk diffusion assay also showed that ATPS extraction has superior internal antibacterial activity with a zone of inhibition diameter at 250 μg/mL of 8.67 ± 1.15 and 5.00 ± 2.00 mm. Meanwhile, those of UA extract on C. acnes is 5.67 ± 1.53 mm (at 1500 μg/mL), and on S. epidermidis is 1.34 ± 0.58 mm (at 156.25 μg/mL).
To sum up, our research highlights the potential of H. cordata ATPS extracts as the starting material for topical preparations for effectively treating acne.
•Successfully utilized aqueous two-phase system (ATPS) with 10% (NH4)2SO4 and 35% ethanol to obtain specific flavonoids-rich extracts.•From the Response Surface Methodology results, the optimal conditions for ATPS extraction were ultrasonic extraction at 50 °C for 30 min, giving results consistent with the predicted model.•ATPS extracts exhibit potential antibacterial activity against Cutibacterium acnes and Staphylococcus epidermidis.
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