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1.
Front Neurol ; 15: 1398830, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38978811

RESUMO

Background and purpose: Ischemic stroke (IS) is classified into clinical subtypes and likely influenced by various lipid components. Nevertheless, the roles of apolipoprotein A-I (apoA-I), apolipoprotein B (apoB), and apoB/apoA-I ratio in different IS subtypes remain underexplored. This study aimed to investigate the differential distribution of plasma apoA-I and apoB levels among IS subtypes and to evaluate the predictive value of the apoB/apoA-I ratio in assessing IS subtypes and disease severity. Methods: In this study, 406 IS patients were categorized into three IS-subtypes based on clinical manifestations and imaging assessment, including intracranial atherosclerosis-related IS patients (ICAS, n = 193), extracranial atherosclerosis-related IS patients (ECAS, n = 111), and small artery occlusion-related IS patients (SAO, n = 102). Plasma apoA-I and apoB levels were measured upon hospital admission. Random forest (RF) models were performed to assess predictive values of these apolipoproteins apoB, apoA-I and their ratio in assessing IS subtype stratification and disease severity. Results: Serum apoA-I levels were significantly lower in ICAS compared to ECAS and SAO patients (p < 0.0001), while apoB levels were higher in ICAS patients (p < 0.0001). The apoB/apoA-I ratio was significantly higher in ICAS compared to ECAS and SAO patients (p < 0.0001). Correlation analyses found a significant correlation between the apoB/apoA-I ratio and conventional lipid components. Additionally, RF models and plots of variable importance and distribution of minimal depth revealed that the apoB/apoA-I ratio played the most influential predictor in predicting IS subtypes and stenosis severity. Conclusion: Our study shows the differential distribution of apoA-I and apoB IS subtypes and reveals the significance of the apoB/apoA-I ratio in assessing IS subtypes and arterial stenosis severity. Further studies are warranted to validate these findings and enhance their clinical applicability.

2.
Materials (Basel) ; 17(13)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38998457

RESUMO

The present study investigates the effects of Er3+ doping content on the microstructure and up-conversion emission properties of CaTiO3: Er3+ phosphors as a potential material in biomedical applications. The CaTiO3: x%Er3+ (x = 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0%) films were synthesized on Ti substrates by a hydrothermal reaction at 200 °C for 24 h. The SEM image showed the formation of cubic nanorod CaTiO3: Er3+ films with a mean edge size value of (1-5) µm. When excited with 980 nm light, the CaTiO3: Er3+ films emitted a strong green band and a weak red band of Er3+ ions located at 543, 661, and 740 nm. The CaTiO3: Er3+ film exhibited excellent surface hydrophilicity with a contact angle of ~zero and good biocompatibility against baby hamster kidney (BHK) cells. CaTiO3: Er3+ films emerge as promising materials for different applications in the biomedical field.

3.
Nat Prod Res ; : 1-7, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771007

RESUMO

Phytochemical study of the leaves of Styrax annamensis Guillaumin resulted in the isolation of a new natural product egonol-3''-sulphate (1), and two new derivatives egonol-3-methyl-D-galactopyranoside (2) and 7-methoxy-2-(3',4'-methylenedioxyphenyl)-benzofuran-5-carboxamide (3). Their chemical structures were -elucidated by spectroscopic data. Compounds 1 and 3 significantly established a great role for the chemotaxonomic aspect. Compound 1 showed cytotoxicity against four cancer cell lines KB, HepG2, Lu, and MCF7 with the IC50 values of 84.90-101.69 µg/mL, and exhibited acetylcholinesterase (AChE) inhibitory activity with the IC50 value of 97.08 µg/mL.

4.
RSC Adv ; 14(8): 5264-5275, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38343997

RESUMO

Epoxy resin has been extensively used in many industrial and daily applications due to its unique properties. However, the high flammability of epoxy has limited its further development. DOPO derivatives, which are organophosphorus compounds, are highly effective components of flame retardant epoxy composites due to their good compatibility with the resin and their lower toxicity compared to halogenated compounds. This study synthesized sixteen new DOPO derivatives, characterizing their chemical structures with NMR spectroscopy. The combination of synthesized DOPO derivatives and APP-PEI (ammonium polyphosphate-polyethyleneimine) has shown a synergistic effect on enhancing the flame retardancy of epoxy resin with the UL-94 V-0 rating and the LOI value of 28.6%. Moreover, the epoxy composites displayed relatively high mechanical performance with the impact strength of 26-28 kJ m-2.

5.
Bioresour Technol ; 394: 130281, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38181996

RESUMO

In this study, the sorption properties of ciprofloxacin, ofloxacin, sulfamethoxazole, and trimethoprim on biochar derived from macadamia nut shells were investigated. The raw biomass was pyrolyzed at 600 °C to create a highly porous material with a surface area of 392 m2 g-1. The produced biochar was found to be a valuable material for both environmental remediation and carbon sequestration due to its high carbon and oxygen content. The sorption properties of four antibiotics on the produced biochar were compared using Bayesian nonlinear regression based on second-order kinetics and the Langmuir model. The Bayesian estimation successfully compared the adsorption coefficients of the antibiotics, which can be directly visualized through graphical grammar using the probability density distribution. The results demonstrated the ability of macadamia nut shell biochar to remove antibiotics from water at neutral pH, and this material has the potential to be used for treating other emerging contaminants.


Assuntos
Antibacterianos , Poluentes Químicos da Água , Antibacterianos/química , Macadamia , Teorema de Bayes , Ciprofloxacina , Carvão Vegetal/química , Adsorção , Poluentes Químicos da Água/química , Cinética
6.
Infect Med (Beijing) ; 2(3): 229-236, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38073881

RESUMO

Background: Strongyloidiasis, a neglected disease caused by intestinal nematodes of the genus, is endemic to tropical and subtropical areas such as Vietnam. Morphological methods only identify the genus, while DNA-molecular techniques are susceptible in Strongyloides spp. detection. The study aims to determine the prevalence of dominant Strongyloides species among the population in Duc Hoa district, Long An, Vietnam. Methods: A cross-sectional study used 1190 stool specimens collected from July 2017 to November 2018. All samples were transported within 2 h, stored at 2-8°C, and processed within 48 h for microscopy smear and culture at the Laboratory of Medical Parasitology, Pham Ngoc Thach University of Medicine (PNT). Then all positive samples with the above 2 methods were verified by real-time PCR technique. Real-time PCR amplification was conducted at the Laboratory of Molecular Biology, PNT. Results: Direct microscopy and modified Harada-Mori culture detected Strongyloides spp. larvae in 79/1190 samples (6.6%). About 94.2% of the DNA samples were Strongyloides stercoralis, 2.9% were co-infections with Strongyloides ratti and S. stercoralis, and 2.9% were patients with S. ratti. The identity of 12/14 sequences was confirmed as S. stercoralis with a high level of similarity (91.3%-100%) and over 98% for S. ratti. Conclusion: DNA-molecular techniques and sequence analysis are highly suitable for identifying Strongyloides species isolated from stool samples. It is remarkable evidence of the presence of zoonosis S. ratti disease in human, not just the known S. stercoralis. It is likely to result in a certain proportion of people being infected by this animal-borne infectious pathogen.

7.
Pharm. pract. (Granada, Internet) ; 21(3): 1-7, jul.-sep. 2023. tab
Artigo em Inglês | IBECS | ID: ibc-226160

RESUMO

This study aimed to determine factors associated with medication errors, and evaluate the results of interventions to reduce medication errors in inpatients treatment at Hoan My Minh Hai General Hospital, Vietnam. Methods: A single-blind, before-and-after and interventional study was conducted on 442 medical records of inpatients in the pre-intervention stage and 442 medical records of inpatients in the post-intervention stage at the Department of Pediatrics, Department of General Internal Medicine, Department of Cardiology - Endocrinology, Department of Surgery, Department of Obstetrics of Hoan My Minh Hai General Hospital from July 1, 2021, to March 31, 2022. Data were collected and processed using Excel 2016 and SPSS 26.0 software. Results: The medication errors rate decreased from 7.70% in the pre-intervention stage to 5.70% in the post-intervention stage, the difference was statistically significant (p<0.001). Medication errors before intervention occurred most often in the preparation and implementation stage (2.04%), after the intervention, the rate decreased to 1.81%. The replication stage had a high rate of medication errors (2.04%), after the intervention it decreased to 1.81%. The most common medication errors before intervention were wrong doses and wrong drugs (1.58%), after intervention, wrong dose errors rate decreased to 1.36%, the rate of wrong drug errors rate decreased to 1.13%. The total number of diseases ≥2 was significantly related to the occurrence of medication errors (p<0.05). Conclusion: Medication errors could occur at different stages of medication use processes. Pharmacist interventions appear to decrease the incidence of medication errors. (AU)


Assuntos
Humanos , Erros de Medicação/prevenção & controle , Hospitalização , Procedimentos Cirúrgicos Operatórios , Vietnã , Método Simples-Cego , Prescrições
8.
Chem Biodivers ; 20(9): e202301037, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37529975

RESUMO

Four undescribed phenolic glycosides including three stilbene derivatives (1 and 3) and sodium salt of 3 (2), and a chalcone glycoside (4), together with thirteen known compounds (5-17) were isolated from the leaves of Syzygium attopeuense (Gagnep.) Merr. & L.M.Perry. Their chemical structures were elucidated to be (Z)-gaylussacin (1), 6''-O-galloylgaylussacin sodium salt (2), 6''-O-galloylgaylussacin (3), 4'-O-[ß-D-glucopyranosyl-(1→6)-glucopyranosyl]oxy-2'-hydroxy-6'-methoxydihydrochalcone (4), gaylussacin (5), pinosilvin 3-O-ß-D-glucopyranoside (6), myricetin-3-O-(2''-O-galloyl)-α-L-rhamnopyranoside (7), myricetin-3-O-(3''-O-galloyl)-α-L-rhamnopyranoside (8), myricetin-3-O-α-L-rhamnopyranoside (9), quercitrin (10), myricetin-3-O-ß-D-glucopyranoside (11), myricetin-3-O-ß-D-galactopyranoside (12), quercetin 3-O-α-L-arabinopyranoside (13), myricetin-3-O-2''-O-galloyl)-α-L-arabinopyranoside (14), (+)-gallocatechin (15), (-)-epigallocatechin (16), and 3,3',4'-trimethoxyellagic acid 4-O-ß-D-glucopyranoside (17) by the analysis of HR-ESI-MS, 1D and 2D NMR spectra in comparison with the previously reported data. Compounds 1-3, 5, and 6 significant inhibition of NO production in LPS-activated RAW264.7 cells, with IC50 values ranging from 18.37±1.38 to 35.12±2.53 µM, compared to a positive control (dexamethasone) with an IC50 value of 15.37±1.42 µM.


Assuntos
Glicosídeos , Syzygium , Glicosídeos/farmacologia , Glicosídeos/química , Óxido Nítrico , Fenóis/farmacologia , Sódio , Estrutura Molecular
9.
J Nat Med ; 77(4): 964-971, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37358723

RESUMO

Three undescribed triterpene glycosides syzybullosides A-C (1-3) along with fourteen known compounds were isolated from the leaves of Syzygium bullockii (Hance) Merr.& L.M. Perry, including six triterpene glycosides (1-6), four phenolics (7-9, 17), four megastigmanes (10-13), and three flavonoids (14-16). The structures of 1-17 were elucidated by extensive spectroscopic analysis, including IR, HR-ESI-MS, 1D and 2D NMR spectra. Compounds 1-10 and 12-17 inhibited nitric oxide (NO) production in lipopolysaccharide activated RAW264.7 cells with IC50 values ranging from 1.30 to 13.70 µM, lower than that of the positive control compound, L-NMMA (IC50 = 33.8 µM).


Assuntos
Syzygium , Triterpenos , Estrutura Molecular , Óxido Nítrico , Glicosídeos/farmacologia , Glicosídeos/química , Triterpenos/farmacologia , Triterpenos/química
10.
Indian J Endocrinol Metab ; 27(1): 37-44, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37215277

RESUMO

Background: Papillary thyroid carcinoma (PTC) is more frequently reported in patients with Hashimoto's thyroiditis (HT), which may be associated with the presence of solid cell nests (SCNs) and focal PTC-like nuclear alterations in the thyroid gland. The point of this consideration was to assess the morphological and immunohistochemical features of SCNs and follicular epithelial changes in Vietnamese patients with HT. Materials and Methods: Hematoxylin-eosin and immunohistochemistry were performed on 20 samples of HT patients who underwent thyroidectomy and were diagnosed with Hashimoto's thyroiditis at Military Medical Hospital 103 from 6/2018 to 6/2019. The expression of five markers (P63, Calcitonin, TTF1, CK19 and HBME-1) in SCNs and follicular epithelial changes were evaluated. Results: Ninety per cent of samples had SCNs with an average of 10 SCNs per section. Only type 1 and type 4 SCNs were presented (85% and 55%, respectively) and all SCNs were composed of main cells (p63-positive). Fifteen of the 18 cases having SCNs possessed nuclear features of PTC. C-cell hyperplasia was found in one case with 20 clusters. All SCNs showed strong staining with CK19 and weak staining with HBME-1. Follicular epithelial changes were Hürthle cell metaplasia, PTC-like nuclear alterations, atypical solid nodules, papillary and glomerular-like forms (40%, 100%, 25% and 50%, respectively). Follicular cells of glomerular-like forms (new alteration) especially were positive with CK19 (2+ ~ 3+), HBME-1 (1+) and TTF1, while the components in these follicles were negative with CK19, HBME-1 and TTF1. Among PTC-like nuclear alterations, all the atypical solid nodules related to HT showed markers related to PTC and without SCNs. Conclusions: Increasing the number of SCNs, as well as PTC-like nuclear alterations of main cells in SCNs and follicular epithelial changes were co-expressed CK19 and HBME-1. Therefore, the need for HT management should be considered.

11.
Chem Biodivers ; 20(3): e202201048, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36879412

RESUMO

A new isopropyl chromone (1) and a new flavanone glucoside (2) together with eleven known compounds (3-13) were isolated from the leaves of Syzygium cerasiforme (Blume) Merr. & L.M.Perry. Their structures were elucidated as 5,7-dihydroxy-2-isopropyl-6,8-dimethyl-4H-chromen-4-one (1), 5,7-dihydroxyflavanone 7-O-ß-D-(6''-O-galloylglucopyranoside) (2), strobopinin (3), demethoxymatteucinol (4), pinocembrin-7-O-ß-D-glucopyranoside (5), (2S)-hydroxynaringenin-7-O-ß-D-glucopyranoside (6), afzelin (7), quercetin (8), kaplanin (9), endoperoxide G3 (10), grasshopper (11), vomifoliol (12), litseagermacrane (13) by the analysis of HR-ESI-MS, NMR, and CD spectral data. Compounds 1, 2, 5, 6 and 10 inhibited NO production on LPS-activated RAW264.7 cells with IC50 values of 12.28±1.15, 8.52±1.62, 7.68±0.87, 9.67±0.57, and 6.69±0.34 µM, respectively, while the IC50 values of the other compounds ranging from 33.38±0.78 to 86.51±2.98 µM, compared to that of the positive control, NG -monomethyl-L-arginine acetate (L-NMMA) with an IC50 value of 32.50±1.00 µM.


Assuntos
Flavanonas , Syzygium , Cromonas/farmacologia , Flavanonas/farmacologia , Glucosídeos/farmacologia , Glucosídeos/química , Estrutura Molecular , Óxido Nítrico , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Syzygium/química
12.
RSC Adv ; 13(11): 7372-7379, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36895775

RESUMO

A novel facile combination of precipitation and plasma discharge reaction is successfully employed for one-step synthesis of an α-Fe2O3-Fe3O4 graphene nanocomposite (GFs). The co-existence and anchoring of hematite (α-Fe2O3) and magnetite (Fe3O4) nanoparticles onto a graphene sheet in the as synthesized GFs were verified by results of XRD, Raman, SEM, TEM, and XPS. HRTEM characterization was used for confirming the bonding between α-Fe2O3/Fe3O4 nanoparticles and the graphene sheet. Consequently, GFs shows superior photodegrading performance towards methylene blue (MB), compared to individual α-Fe2O3/Fe3O4 nanoparticles, as a result of band gap narrowing and the electron-hole pair recombination rate reducing. Moreover, GFs allows a good possibility of separating and recycling under an external-magnetic field, suggesting potential in visible-light-promoted photocatalytic applications.

13.
Vet Res Commun ; 47(3): 1773-1776, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36823481

RESUMO

African swine fever virus (ASFV) causes African swine fever (ASF), a deadly disease affecting both domestic pigs and wild boars. ASF has become endemic in Vietnam since its first appearance in early 2019. Our previous molecular surveillance studies revealed that all the ASFV strains circulating in Vietnam belong to p72 genotype II, p54 genotype II, CD2v serogroup 8, and CVR of B602L gene variant type I. However, the genetic analysis based on the tandem repeat sequences located between I73R and I329L genes revealed three different intergenic region (IGR) variants; I, II, and III. In this study, using ASFV field isolates collected from September 24th to December 27th, 2021, we report, for the first time, novel IGR IV variants circulating in the Vietnamese pig population.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Doenças dos Suínos , Suínos , Animais , Sus scrofa , Vírus da Febre Suína Africana/genética , Febre Suína Africana/epidemiologia , Febre Suína Africana/genética , DNA Intergênico/genética , Vietnã/epidemiologia , Surtos de Doenças , Filogenia , Genótipo , Doenças dos Suínos/epidemiologia
14.
Phytother Res ; 37(6): 2395-2404, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36751127

RESUMO

The number of COVID-19 infections is still increasing with the omicron variant. Although vaccination has shown its effectiveness, efficacious treatments are still required. Kovir, a Vietnamese herbal medicine, has shown potential effects for non-severe COVID-19 patients in terms of symptom resolution and prevention of disease progression in previous studies. This phase-3 trial evaluated the safety and efficacy of Kovir for non-severe COVID-19 adults. Participants were randomized to the Kovir (381 patients) or placebo (192 patients) groups. Outcomes were progression to severe/critical COVID-19, a daily symptom score based on 11 pre-defined symptoms, time to symptom resolution, a negative reverse transcription polymerase chain reaction, an EQ-5D-5L quality of life (QOL) score, and serious adverse events. Only one patient (in the placebo group) progressed to severe COVID-19, thus we could not conclude the effect of Kovir on the prevention of disease progression. Kovir significantly reduced time to symptom resolution (median: 7 vs. 11 days, hazard ratio [95% confidence interval]: 2.03 [1.66-2.48]) compared to placebo. Kovir also increased the QOL score on days 7 and 14. No safety concerns were observed. To conclude, Kovir is safe and facilitates symptom relief for non-severe COVID-19 patients. We advocate using Kovir in the early phase of COVID-19 for non-severe adult patients.


Assuntos
COVID-19 , Adulto , Humanos , COVID-19/terapia , Progressão da Doença , Método Duplo-Cego , Qualidade de Vida , SARS-CoV-2 , População do Sudeste Asiático , Resultado do Tratamento , Tratamento Farmacológico da COVID-19 , Fitoterapia , Vietnã , Medicina Tradicional
15.
Nat Prod Res ; 37(2): 305-312, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34498962

RESUMO

A new muurolane-type sesquiterpene, a new flavone arabinofuranoside derivative, and other five known flavone arabinofuranoside derivatives were isolated from the leaves of Fissistigma bicolor (Annonaceae family). Their chemical structures were determined to be (1S,6R,7S)-muurola-4,10(14)-diene-15-ol (1), quercetin 3-O-ß-D-apiofuranosyl-(1→2)-α-L-arabinofuranoside (2), quercetin 3-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinofuranoside (3), quercetin 3-O-α-L-arabinofuranoside (4), kaempferol 3-O-ß-D-apiofuranosyl-(1→2)-α-L-arabinofuranoside (5), kaempferol 3-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinofuranoside (6), and kaempferol 3-O-α-L-arabinofuranoside (7) by analyses of HR-ESI-MS and NMR spectral data. Compounds 4 and 7 containing monosaccharide, arabinofuranoside, potentially inhibited NO productions in LPS activated RAW264.7 cells (IC50 13.4 ± 0.5 and 12.6 ± 0.4 µM) in compared to disaccharide derivatives (IC50 ranging from 58.9 ± 3.3 to 65.6 ± 3.8 µM).


Assuntos
Annonaceae , Flavonas , Quempferóis/análise , Quercetina , Annonaceae/química , Flavonas/farmacologia , Flavonas/análise , Glicosídeos/química , Folhas de Planta/química , Estrutura Molecular
16.
Nat Prod Res ; 37(1): 77-84, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34338100

RESUMO

Three new xanthones, garcimckeans A-C (1-3) were isolated from the methanol extract of the stems of Garcinia mckeaniana (Clusiaceae). Their structures were established by extensive spectroscopic analysis (HR-ESI-MS and 1 D and 2 D NMR) and by comparison of the spectral data with those reported in the literature. Compounds 1-3 displayed weak cytotoxic activity toward KB, Lu, HepG2, and MCF7 cell lines using the MTT assay with IC50 values ranging from 71.03 ± 2.93 to 90.40 ± 7.13 µM compared to that of the positive control compound, ellipticine (IC50: 1.22 ± 0.10 ∼ 2.44 ± 0.2 µM).


Assuntos
Antineoplásicos Fitogênicos , Antineoplásicos , Garcinia , Xantonas , Humanos , Garcinia/química , Estrutura Molecular , Xantonas/farmacologia , Xantonas/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Células MCF-7
17.
Chem Biodivers ; 20(2): e202200456, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36564341

RESUMO

The current report describes the chemical investigation and biological activity of extracts produced by three fungal strains Fusarium oxysporum, Penicillium simplicissimum, and Fusarium proliferatum isolated from the roots of Piper nigrum L. growing in Vietnam. These fungi were namely determined by morphological and DNA analyses. GC/MS identification revealed that the EtOAc extracts of these fungi were associated with the presence of saturated and unsaturated fatty acids. These EtOAc extracts showed cytotoxicity towards cancer cell lines HepG2, inhibited various microbacterial organisms, especially fungus Aspergillus niger and yeast Candida albicans (the MIC values of 50-100 µg/mL). In α-glucosidase inhibitory assay, they induced the IC50 values of 1.00-2.53 µg/mL were better than positive control acarbose (169.80 µg/mL). The EtOAc extract of F. oxysporum also showed strong anti-inflammatory activity against NO production and PGE-2 level. Four major compounds linoleic acid (37.346 %), oleic acid (27.520 %), palmitic acid (25.547 %), and stearic acid (7.030 %) from the EtOAc extract of F. oxysporum were selective in molecular docking study, by which linoleic and oleic acids showed higher binding affinity towards α-glucosidase than palmitic and stearic acids. In subsequent docking assay with inducible nitric oxide synthase (iNOS), palmitic acid, oleic acid and linoleic acid could be moderate inhibitors.


Assuntos
Piper nigrum , Ácido Oleico , alfa-Glucosidases , Simulação de Acoplamento Molecular , Fungos , Extratos Vegetais/farmacologia , Ácido Palmítico , Ácidos Linoleicos
18.
Sci Total Environ ; 862: 160802, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36493814

RESUMO

In this study, the operation parameters of a partial nitrification process (PN) treating saline wastewater were optimized using the Box-Behnken design via the response surface methodology (BBD-RSM). A novel strategy based on the control of the carbon/nitrogen ratio (C/N), alkalinity/ammonia ratio (K/A), and salinity in three stages was used to achieve PN in a sequence batch reactor. The results demonstrated that a high and stable PN was completed after 50 d with an ammonia removal efficiency (ARE) of 98.37 % and nitrite accumulation rate (NAR) of 85.93 %. Next, BBD-RSM was applied, where ARE and NAR were the responses. The highest responses from the confirmation experiment were 99.9 % ± 0.04 and 95.25 % ± 0.32 when the optimum C/N, K/A, and salinity were identified as 0.84, 2, and 5.5 (g/L), respectively. The results were higher than those for the nonoptimized reactor. The developed regression model adequately forecasts the PN performance under optimal conditions. Therefore, this study provides a promising strategy for controlling the PN process and shows how the BBD-RSM model can improve the PN performance.


Assuntos
Nitrificação , Águas Residuárias , Amônia , Salinidade , Reatores Biológicos , Nitrogênio , Nitritos , Carbono , Oxirredução , Esgotos , Desnitrificação
20.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-1002640

RESUMO

Objectives@#Tuberculosis (TB) and drug-resistant TB (DR-TB) are national health burdens in Vietnam. In this study, we investigated the prevalence of rifampicin (RIF) and/or isoniazid (isonicotinic acid hydrazide, INH) resistance in patients with suspected TB, and applied appropriate techniques to help rapidly target DR-TB. @*Methods@#In total, 1,547 clinical specimens were collected and cultured using the BACTEC MGIT system (Becton Dickinson and Co.). A resazurin microtiter assay (REMA) was used to determine the proportions of RIF and/or INH resistance. A real-time polymerase chain reaction panel with TaqMan probes was employed to identify the mutations of rpoB and katG associated with DR-TB in clinical isolates. Genotyping of the identified mutations was also performed. @*Results@#A total of 468 Mycobacterium tuberculosis isolates were identified using the REMA. Of these isolates, 106 (22.6%) were found to be resistant to 1 or both antibiotics. Of the resistant isolates, 74 isolates (69.8%) were resistant to isoniazid (INH) only, while 1 isolate (0.94%) was resistant to RIF only. Notably, 31 isolates (29.24%) were resistant to both antibiotics. Of the 41 phenotypically INH-resistant isolates, 19 (46.3%) had the Ser315Thr mutation. There were 8 different rpoB mutations in 22 (68.8%) of the RIF-resistant isolates. The most frequently detected mutations were at codons 531 (37.5%), 526 (18.8%), and 516 (6.3%). @*Conclusion@#To help prevent new cases of DR-TB in Vietnam, it is crucial to gain a comprehensive understanding of the genotypic DR-TB isolates.

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