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Pluchea indica (L.) Less. is a medicinal plant native to Asia. Traditionally, it is known for numerous traditional uses, such as treatments for fever, cough, and digestive issues. The present investigation aims to determine the chemical compositions of essential oils from its fresh leaves and stem barks. By using hydro-distillation and the GC-FID/MS (gas chromatography-flame ionization detection/mass spectrometry) analysis, the studied samples were dominated by sesquiterpene hydrocarbons (76.8-82.2%) and their oxygenated derivatives (8.4-19.0%). ß-Selinene (42.0-43.5%) and silphinene (21.1-22.9%) were the main compounds. Significantly, the stem bark essential oil strongly monitored the growth of four cancer cell lines K562, HeLa, HepG2, and MCF-7 with IC50 values of 2.89-7.34 µg/mL. Both studied samples showed strong anti-inflammatory activity against NO (nitric oxide) production with IC50 values of 21.81-23.18 µg/mL. The studied sample also exhibited antimicrobial activity at different levels. The molecular docking study revealed that ß-selinene exhibited the strongest binding affinity for all four cancer-related protein targets: epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), Abelson tyrosine-protein kinase 1 (ABL1), and phosphatidylinositol 3-kinase (PI3K-α). The ADMET profiles of the major compounds were also predicted to provide insights for further research considerations.

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Bioaccessibility of halogenated flame retardants (HFRs) and organophosphorus esters (OPEs) is necessarily investigated to provide more accurate risk assessment and information about absorption behavior of these pollutants. In this study, total and bioaccessible concentrations of HFRs (including legacy and alternative substances) and OPEs were determined in settled dust samples collected from Vietnamese e-waste and end-of-life vehicle (ELV) processing areas. Concentrations of both HFRs and OPEs were significantly higher in the e-waste dust than ELV dust. Bioavailability of HFRs and OPEs in dust was determined by using an in vitro assay with human-simulated digestive fluids, dialysis membrane, and Tenax® TA sorptive sink. Bioaccessibility of HFRs was markedly lower than that of OPEs, which could be largely due to higher hydrophobicity of HFRs compared to OPEs. Bioaccessibility of almost hydrophobic compounds were markedly lower in the e-waste dust (containing micronized plastic debris) than in the ELV dust (containing oily materials), suggesting the influence of specific dust matrices on pollutant bioaccessibility. Although the daily uptake doses of selected HFRs and OPEs from dust were markedly higher in the e-waste sites compared to the ELV sites, the direct exposure risk was not significant. Our results suggest that bioaccessibility can partly explain the differences between dust and uptake profiles, which may relate to accumulation profiles of HFRs and OPEs in human samples.

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Aims@#Microorganisms play a vital role in the breakdown of natural organic compounds and are valuable objects for worldwide enzyme production. The aim of this study was to identify favorable production conditions for Bacillus amyloliquefaciens D19 protease, followed by the purification and chemical characterization of this novel enzyme to assess its potential applications in various fields.@*Methodology and results@#In this study, favorable conditions of protease production from B. amyloliquefaciens D19 were determined using a medium containing soluble starch (1.5%), earthworm extract (1.0%), yeast extract (0.5%), NaCl (1.0%), at pH 7.0-8.0, 37 °C for 36 h with 150 rpm shaking condition. The protease was purified and had a molecular weight of about 23 kDa. The optimum condition for casein hydrolysis was at 40 °C and pH 6.5-7.0 in the presence of 1.0 mM Na+ or 5.0 mM Zn2+. The enzymatic activity was maintained at 75-100% at 30-50 °C and in pH 6.0-10.0. The values of Vmax and KM were also determined as 1547 U/mg and 6.33 mg/mL, respectively.@*Conclusion, significance and impact of study@#The identified optimal conditions will serve as the foundation for the production of the 23 kDa B. amyloliquefaciens D19 protease, one of the smallest proteases within the Bacillus genus. Moreover, its notable heat resistance, broad pH tolerance, high substrate catalysis and moderate substrate binding affinity make this enzyme a promising candidate for various applications in the food-feed and brewing industries.

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In Asian developing countries, undeveloped and ineffective sewer systems are causing surface water pollution by a lot of contaminants, especially pharmaceuticals and personal care products (PPCPs). Therefore, the risks for freshwater fauna need to be assessed. The present study aimed at: i) elucidating the contamination status; ii) evaluating the bioaccumulation; and iii) assessing the potential risks of PPCP residues in surface water and freshwater fish from three Asian countries. We measured 43 PPCPs in the plasma of several fish species as well as ambient water samples collected from India (Chennai and Bengaluru), Indonesia (Jakarta and Tangerang), and Vietnam (Hanoi and Hoa Binh). In addition, the validity of the existing fish blood-water partitioning model based solely on the lipophilicity of chemicals is assessed for ionizable and readily metabolizable PPCPs. When comparing bioaccumulation factors calculated from the PPCP concentrations measured in the fish and water (BAFmeasured) with bioconcentration factors predicted from their pH-dependent octanol-water partition coefficient (BCFpredicted), close values (within an order of magnitude) were observed for 58-91 % of the detected compounds. Nevertheless, up to 110 times higher plasma BAFmeasured than the BCFpredicted were found for the antihistamine chlorpheniramine in tilapia but not in other fish species. The plasma BAFmeasured values of the compound were significantly different in the three fish species (tilapia > carp > catfish), possibly due to species-specific differences in toxicokinetics (e.g., plasma protein binding and hepatic metabolism). Results of potential risk evaluation based on the PPCP concentrations measured in the fish plasma suggested that chlorpheniramine, triclosan, haloperidol, triclocarban, diclofenac, and diphenhydramine can pose potential adverse effects on wild fish. Results of potential risk evaluation based on the PPCP concentrations measured in the surface water indicated high ecological risks of carbamazepine, sulfamethoxazole, erythromycin, and triclosan on Asian freshwater ecosystems.

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Two new phenolic glycosides, 4-(3-hydroxypropyl)-2,6-dimethoxyphenol ß-D-apiofuranosyl-(1→6)-ß-D-glucopyranoside (1), trans-cinnamyl alcohol 9-O-(6'-O-ß-D-apiofuranosyl)-ß-D-glucopyranoside (2), together with nine known phenolic glycosides (3-11) were isolated from the roots of Pandanus tonkinensis. Their structures were determined by extensive analysis of HRESIMS and NMR spectral data, as well as by comparison of their spectral data (including CD spectra) with those reported in the literature. Compounds 1-4 and 6-11 inhibited NO production in LPS-activated RAW264.7 cells with IC50 values in the range from 0.80 ± 0.06 µM to 43.38 ± 3.92 µM, whereas compound 5 was inactive. The NO production inhibitory activities of compounds 1, 4, 8, and 10 with IC50 values of 10.16 ± 1.05, 0.80 ± 0.06, 1.10 ± 0.13, and 2.79 ± 0.21 µM, respectively, are as potent as that of the positive control of NG-monomethyl-L-arginine acetate (L-NMMA) with an IC50 value of 9.80 ± 0.78 µM.

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Estrogen, androgen, and glucocorticoid receptors (ER, AR, and GR) agonist activities in river water samples from Chennai and Bangalore (India), Jakarta (Indonesia), and Hanoi (Vietnam) were evaluated using a panel of chemical-activated luciferase gene expression (CALUX) assays and were detected mainly in the dissolved phase. The ER agonist activity levels were 0.011-55 ng estradiol (E2)-equivalent/l, higher than the proposed effect-based trigger (EBT) value of 0.5 ng/l in most of the samples. The AR agonist activity levels were < 2.1-110 ng dihydrotestosterone (DHT)-equivalent/l, and all levels above the limit of quantification exceeded the EBT value of 3.4 ng/l. GR agonist activities were detected in only Bangalore and Hanoi samples at dexamethasone (Dex)-equivalent levels of < 16-150 ng/l and exceeded the EBT value of 100 ng/l in only two Bangalore samples. Major compounds contributing to the ER, AR, and GR agonist activities were identified for water samples from Bangalore and Hanoi, which had substantially higher activities in all assays, by using a combination of fractionation, CALUX measurement, and non-target and target chemical analysis. The results for pooled samples showed that the major ER agonists were the endogenous estrogens E2 and estriol, and the major GR agonists were the synthetic glucocorticoids Dex and clobetasol propionate. The only AR agonist identified in major androgenic water extract fractions was DHT, but several unidentified compounds with the same molecular formulae as endogenous androgens were also found.

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Electrical and electronic waste (e-waste) has become a global concern, especially in developing countries. In this review, we conducted a literature survey of e-waste management practices, processing activities, and adverse effects in Vietnam, an emerging country in Southeast Asia, by gathering data from peer-reviewed articles published between 2009 and 2021. This is the first review paper to comprehensively discuss management and research aspects regarding e-waste in an Asian developing country. Due to the lack of an effective management and recycling system, a certain portion of Vietnamese e-waste has been processed by informal sectors without appropriate recycling and pollution control technology, resulting in localized contamination and human exposure to toxic chemicals. Primitive processing activities, such as manual dismantling, open burning, and plastic recycling, have been identified as important contributors to the environmental emission and human exposure to toxic elements (notably As, Mn, Ni, Pb, Zn) and organic pollutants like flame retardants, PAHs, PCBs, and dioxin-related compounds. Informal e-waste processing from these small-scale workshops can release pollutants at similar levels compared to large-scale facilities in developed countries. This fact suggests an urgent need to develop management best practices for e-waste in Vietnam as well as other emerging and developing countries, in order to increase recycling efficiency and minimize their adverse impacts on environmental and human health.

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Measuring personal exposure to flame retardants (FRs) is crucial for assessing and controlling human health risks posed by FRs during the recycling of electronic waste (e-waste) and end-of-life vehicles (ELVs). Here, we examined the use of handwipes and silicone wristbands to measure personal FR exposure for e-waste and ELV recycling workers and their children in Vietnam. On the handwipes from the e-waste recycling workers, the predominant five FRs detected were TBBPA (median concentration: 3700 ng/wipe), BDE-209 (1700 ng/wipe), TPHP (500 ng/wipe), DBDPE (410 ng/wipe), and BPA-BDPP (360 ng/wipe). On the handwipes from ELV recycling workers, TPHP (60 ng/wipe), IPPDPP (47 ng/wipe), BIPPPP/DIPPDPP (33 ng/wipe), BDE-209 (26 ng/wipe), and TCIPP (23 ng/wipe) were detected as the five predominant FRs. On the wristbands from the e-waste recycling workers, the five predominant FRs detected were TBBPA (median concentration: 340 ng/g), BDE-209 (330 ng/g), DBDPE (65 ng/g), TPHP (50 ng/g), and TMPP (34 ng/g). On the wristbands from the ELV recycling workers, TPHP (34 ng/g), IPPDPP (18 ng/g), TCIPP (14 ng/g), TDMPP (13 ng/g), BIPPPP/DIPPDPP (9.3 ng/g) and TMPP (9.3 ng/g) were detected as the predominant FRs. The data obtained with the wristbands were comparable to those obtained with the handwipes. Similar FR profiles were found in between the workers and their children. The profiles indicate that the informal e-waste and ELV recycling caused FR exposure not only for workers but also for their children who live in the workshops. By using the handwipe and wristband sampling approaches, we determined types and concentrations of FRs to which the workers and their children were dominantly exposed. Silicone wristband- and handwipe-based assessment is expected to be effective means of measuring personal FR exposure for the informal e-waste and ELV recycling workers and their children.

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The accumulation profiles of nine perfluoroalkyl substances (PFASs) were determined in 95 muscle samples of seven freshwater (n = 65) and seven marine (n = 30) fish species collected in Northern Vietnam. In both groups of fish, perfluorooctane sulfonic acid (PFOS) was the most prevalent component, accounting for roughly 29 % of total PFASs. The total PFASs in freshwater fish species ranged from 0.08 to 8.06 ng/g wet weight (w.w), with the highest concentration found in topmouth culter (7.01 ± 1.23 ng/g w.w). In marine fish, the highest mean concentration of PFASs was detected in Asian sea bass (2.75 ± 0.54 ng/g, w.w). Estimation on the human dietary intake of PFASs from fish consumption resulted in hazard ratios (HR) ranging from 0.019 to 0.238 for freshwater fish and from 0.016 to 0.074 for marine fish, indicating low exposure risks associated with PFASs.

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Information about the co-occurrence of halogenated flame retardants (HFRs) and organophosphate esters (OPEs) in the environment of informal waste processing areas is still limited, especially in emerging and developing countries. In this study, OPEs and HFRs including polybrominated diphenyl ethers (PBDEs), novel brominated flame retardants (NBFRs), and chlorinated flame retardants (CFRs) were determined in settled dust from Vietnamese e-waste recycling (WR) and vehicle processing (VP) workshops. Pollutant concentrations decreased in the order: OPEs (median 1500; range 230-410,000 ng/g) ≈ PBDEs (1200; 58-250,000) > NBFRs (140; not detected - 250,000) > CFRs (13; 0.39-2200). HFR and OPE levels in the WR workshops for e-waste and obsolete plastic were significantly higher than in the VP workshops. Decabromodiphenyl ether and decabromodiphenyl ethane are major HFRs, accounting for 60 ± 26% and 25 ± 29% of total HFRs, respectively. Triphenyl phosphate, tris(2-chloroisopropyl) phosphate, and tris(1,3-dichloroisopropyl) phosphate dominated the OPE profiles, accounting for 30 ± 25%, 25 ± 16%, and 24 ± 18% of total OPEs, respectively. The OPE profiles differed between WR and VP dust samples, implying different usage patterns of these substances in polymer materials for electric/electronic appliance and automotive industries. Human health risk related to dust-bound HFRs and OPEs in the study areas was low.

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The chemical pollution crisis severely threatens human and environmental health globally. To tackle this challenge the establishment of an overarching international science-policy body has recently been suggested. We strongly support this initiative based on the awareness that humanity has already likely left the safe operating space within planetary boundaries for novel entities including chemical pollution. Immediate action is essential and needs to be informed by sound scientific knowledge and data compiled and critically evaluated by an overarching science-policy interface body. Major challenges for such a body are (i) to foster global knowledge production on exposure, impacts and governance going beyond data-rich regions (e.g., Europe and North America), (ii) to cover the entirety of hazardous chemicals, mixtures and wastes, (iii) to follow a one-health perspective considering the risks posed by chemicals and waste on ecosystem and human health, and (iv) to strive for solution-oriented assessments based on systems thinking. Based on multiple evidence on urgent action on a global scale, we call scientists and practitioners to mobilize their scientific networks and to intensify science-policy interaction with national governments to support the negotiations on the establishment of an intergovernmental body based on scientific knowledge explaining the anticipated benefit for human and environmental health.

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Plastic pollution has become one of the most pressing environmental issues. Recycling is a potential means of reducing plastic pollution in the environment. However, plastic fragments are still likely released to the aquatic environment during mechanical recycling processes. Here, we examined the plastic inputs and effluent outputs of three mechanical recycling facilities in Vietnam dealing with electronic, bottle, and household plastic waste, and we found that large quantities of microplastics (plastics <5 mm in length) are generated and released to the aquatic environment during mechanical recycling without proper treatment. Comparisons with literature data for microplastics in wastewater treatment plant effluents and surface water indicated that mechanical recycling of plastic waste is likely a major point source of microplastics pollution. Although there is a mismatch between the size of the microplastics examined in the present study and the predicted no-effect concentration reported, it is still possible that microplastics generated at facilities pose risks to the aquatic environment because there might be many plastic particulates smaller than 315 µm, as suggested by our obtained size distributions. With mechanical recycling likely to increase as we move to a circular plastics economy, greater microplastics emissions can be expected. It is therefore an urgent need to fully understand not only the scale of microplastic generation and release from plastic mechanical recycling but also the environmental risk posed by microplastics in the aquatic environment.

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Perinatal tuberculosis (TB) is a rare disease with severe clinical conditions that may spread to several organs. Early diagnosis to initiate an anti-TB regimen is key to saving patients. We report the successful treatment of two preterm babies with perinatal TB and sepsis at the National Children's Hospital (NCH), Vietnam.

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The ubiquitous distribution of microplastics (MP) is a serious environmental issue in Asian countries. In this study, 54 open-dumping site soils collected from Cambodia, India, Indonesia, Laos, the Philippines, and Vietnam were analyzed for MP. Soil samples were also divided into light (floating) and heavy (sedimentation) fractions by density separation and analyzed for plastic additives. The highest abundance of MP was found in a soil from Cambodia at 218,182 pieces/kg. The median of MP in soils ranged from 1411 pieces/kg in India to 24,000 pieces/kg in the Philippines, suggesting that dumping sites are a major source of MP into the environment. Polyethylene, polypropylene, and polyethylene terephthalate were dominant polymers in soil samples analyzed. This indicates that daily-used plastic products are main sources of MP in dumping site soils in Asian countries. The high concentrations and burdens of phthalates and an antioxidant were detected in floating fraction accounting for 40 to 60% of the total additives in soils. Previous studies on soil pollution have assumed that the organic hydrophobic chemicals analyzed are adsorbed on the surface of soil particles. However, this result indicates that approximately half of the additives in dumping site soils were derived from MP, not soil particle. Monitoring study on soil pollution should be considered the occurrence of MP in the matrices.

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Urban dust has been contaminated with toxic heavy metals from various diffused sources. On August 28, 2019, the compact fluorescence lamp (CFL) factory that generates light for Rang Dong Light Source and Vacuum Flask in Hanoi City in Vietnam was accidentally fired. The assessment for Hg contamination and its human health impact 2 months after the incident was conducted in autumn 2019. The heavy Hg pollution is still found near CFL. Additionally, localized Hg pollution by air and wind direction was identified at sites in the northeast direction from CFL. Namely, in the area located downstream of the southwest monsoon wind, Hg had a trend higher than other directions. The hazard quotient (HQ) and the hazard index (HI) were evaluated by four routes of Hg exposure pathways. The HI values for children and adults in the most polluted site (Site 15) were 0.968 and 0.468, respectively. This meant that children who lived around this site and commuted to schools were the most at risk regarding the potential adverse health effects of Hg in street dust around the polluted areas. This study also showed that Hg levels were affected by wind direction and that the higher Hg levels in the most polluted sites resulted from the wind flow to the sites. This study revealed that street dust may be a useful tool for the assessment of human and environmental health.

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BackgroundHospitalized patients with COVID-19 experience high mortality rates, ranging from 10% to 30%. Combined casirivimab and imdevimab (CAS+IMD) is authorized for use in outpatients with COVID-19 and in post-exposure prophylaxis. The UK-based platform RECOVERY study reported improved survival in hospitalized seronegative patients treated with CAS+IMD; however, in most of the world, anti-spike monoclonal antibody therapy is currently not approved for hospitalized patients. MethodsIn this phase I/II/III double-blind placebo-controlled trial, patients hospitalized with COVID-19 were randomized (1:1:1) to 2.4 g or 8.0 g of CAS+IMD or placebo, and characterized at baseline for viral load and SARS-CoV-2 endogenous immune response. Results1336 patients on low-flow or no supplemental oxygen were treated. The primary endpoint was met: in seronegative patients, the least squares mean difference (CAS+IMD vs placebo) for time-weighted average change from baseline viral load was -0.28 log10 copies/mL (95% confidence interval [CI] -0.51 to -0.05; P = .0172). The primary clinical analysis of death or mechanical ventilation from day 6 to 29 in patients with high viral load had a strong positive trend but did not reach significance. CAS+IMD numerically reduced all-cause mortality in seronegative patients through day 29 (relative risk reduction, 55.6%; 95% CI 24.2-74.0; nominal P = .0032). No safety concerns were noted. ConclusionsIn hospitalized patients with COVID-19 on low-flow or no oxygen, CAS+IMD treatment reduced viral load and the risk of death or mechanical ventilation as well as all-cause mortality in the overall population, with the benefit driven by seronegative patients and no harm observed in seropositive patients.

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Dye and heavy metal contaminants are mainly aquatic pollutants. Although many materials and methods have been developed to remove these pollutants from water, effective and cheap materials and methods are still challenging. In this study, highly porous hydroxyapatite/graphene oxide/chitosan beads (HGC) were prepared by a facile one-step method and investigated as efficient adsorbents. The prepared beads showed a high porosity and low bulk density. SEM images indicated that the hydroxyapatite (HA) nanoparticles and graphene oxide (GO) nanosheets were well dispersed on the CTS matrix. FT-IR spectra confirmed good incorporation of the three components. The adsorption behavior of the obtained beads to methylene blue (MB) and copper ions was investigated, including the effect of the contact time, pH medium, dye/metal ion initial concentration, and recycle ability. The HGC beads showed rapid adsorption, high capacity, and easy separation and reused due to the porous characteristics of GO sheets and HA nanoparticles as well as the rich negative charges of the chitosan (CTS) matrix. The maximum sorption capacities of the HGC beads were 99.00 and 256.41 mg g-1 for MB and copper ions removal, respectively.

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Mercury (Hg), cadmium (Cd), and lead (Pb) concentrations in marketed cigarettes from South Korea, Vietnam, Japan, Indonesia, Taiwan, Thailand, the United Kingdom (UK), Belgium, Italy, Finland, and France were investigated. The cigarettes from Vietnam and Thailand had the highest trend of Hg. Meanwhile, Cd was found higher in cigarettes from Thailand, the UK, and Belgium. Pb concentrations in cigarettes from Belgium, the UK, and Korea were higher than others. The average of these heavy metals concentrated in cigarettes was in the order of Pb > Cd > Hg. Furthermore, the contents of these heavy metals in cigarette leaves were much higher than in filter and rolling paper. There was a significant positive correlation between Hg and Cd, but no correlation between Cd and Pb and between Hg and Pb. Significant positive correlations of nicotine with Hg and Cd but not Pb in the cigarette were observed. Activated carbon filters (Ce-C) absorb Cd and Pb from cigarette leaves and rolling paper indicated a higher trapping trend than cellulose acetate filter without activated carbon (Ce). The trapping ratios of Ce-C (Cd: 5.53%, Pb:5.41%) were higher than Ce (Cd:3.09%, Pb:5.49%). On the other hand, Hg had lower absorption by both types of filters (Ce:0.15%, Ce-C:0.02%). This revealed that Hg, Cd and Pb absorption ability by both filters was relatively lower to the total concentration of these metals in tobacco leaves and rolling paper. The concern was that the higher concentrations of metals such as Hg, Cd and Pb in cigarettes might exist in mainstream smoke.

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BACKGROUND: Estimating the cost of postoperative respiratory complications is crucial in developing appropriate strategies to mitigate the global and national economic burden. However, systematic analysis of the economic burden in low- and middle-income countries is lacking. METHODS: We used the nationwide database of the Vietnam Social Insurance agency and extracted data from January 2017 to September 2018. The data contain 1 241 893 surgical patients undergoing one of seven types of surgery. Propensity score matching method was used to match cases with and without complications. We used generalized gamma regressions to estimate the direct medical costs; logistic regressions to evaluate the impact of postoperative respiratory complications on re-hospitalization and outpatient visits. FINDINGS: Postoperative respiratory complications increased the odds of re-hospitalization and outpatient visits by 3·49 times (95% CI: 3·35-3·64) and 1·39 times (95% CI: 1·34-1·45) among surgical patients, respectively. The mean incremental cost associated with postoperative respiratory complications occurring within 30 days of the index admission was 1053·3 USD (95% CI: 940·7-1165·8) per procedure, which was equivalent to 41% of the GDP per capita of Vietnam in 2018. We estimated the national annual incremental cost due to respiratory complications occurring within 30 days after surgery was 13·87 million USD. Pneumonia contributed the greatest part of the annual cost burden of postoperative respiratory complications. INTERPRETATION: The economic burden of postoperative respiratory complications is substantial at both individual and national levels. Postoperative respiratory complications also increase the odds of re-hospitalization and outpatient visits and increase the length of hospital stay among surgical patients. FUNDING: The authors did not receive any funds for conducting this study.

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Pharmaceutical drugs' removal from wastewater by photocatalytic oxidation process is considered as an attractive approach and environmentally friendly solution. This report aims to appraise the practical application potential of Ag/g-C3N4/ZnO nanorods toward the wastewater treatment of the pharmaceutical industry. The catalysts are synthesized by straightforward and environmentally-friendly strategies. Specifically, g-C3N4/ZnO nanorods heterostructure is constructed by a simple self-assembly method, and then Ag nanoparticles are decorated on g-C3N4/ZnO nanorods by a photoreduction route. The results show that three commercial drugs (paracetamol, amoxicillin, and cefalexin) with high concentration (40 mg L-1) are significantly degraded in the existence of a small dosage of Ag/g-C3N4/ZnO nanorods (0.08 g L-1). The Ag/g-C3N4/ZnO nanorods photocatalyst exhibits degradation performance of paracetamol higher 3.8, 1.8, 1.3 times than pristine g-C3N4, ZnO nanorods, and g-C3N4/ZnO nanorods. Furthermore, Ag/g-C3N4/ZnO nanorods have an excellent reusability and a chemical stability that achieved paracetamol degradation efficiency of 78% and remained chemical structure of the photocatalyst after five cycles. In addition, the photocatalytic mechanism explanation and comparison of photocatalytic drugs' degradation ability have also been discussed in this study.

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