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1.
Nanotechnology ; 35(26)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38527359

RESUMO

A novel, rapid, and facile method for one-step sonoelectrochemical synthesis of zinc oxide nanoparticles (UEZ) was introduced in this study. The optimum operating parameters have been selected at a voltage of 7.5 V, KCl concentration of 0.5 M, and the reaction time of 60 min. The as-prepared UEZ were characterized by XRD, SEM, and HRTEM. It was found that the UEZ has a hexagonal wurtzite structure with high crystalline quality, good purity, a size range of 30-100 nm, and good photocatalytic degradation of methylene blue. This work provides a facile route for large-scale synthesizing ZnO nanoparticles via anodization.

2.
Molecules ; 28(6)2023 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-36985550

RESUMO

The essential oils (EOs) of the aerial parts of four Asarum species (A. geophilum, A. yentunensis, A. splendens and A. cordifolium) were isolated by steam distillation and analyzed by the GC/MS method. The A. cordifolium EO contains 33 constituents with the main component being elemicine (77.20%). The A. geophilum EO was contains 49 constituents with the main components being determined as 9-epi-(E)-caryophyllene (18.43%), eudesm-7(11)-en-4-ol (13.41%), ß-caryophyllene (8.05%) and phytol (7.23%). The A. yentunensis EO contains 26 constituents with the main components being safrole (64.74%) and sesquicineole (15.34%). The EO of A. splendens contains 41 constituents with the main components being 9-epi-(E)-caryophyllene (15.76%), eudesm-7(11)-en-4-ol (14.21%), ß-caryophyllene (9.52%) and trans-bicyclogermacrene (7.50%). For antimicrobial activity, the A. yentunensis EO exhibited the highest inhibition activity against Staphylococcus aureus and the A. cordifolium EO against Bacillus subtillis (MIC values of 100 µg/mL). For antioxidant activity, the A. geophilum EO showed the highest potential with an SC (%) value of 63.34 ± 1.0%, corresponding to an SC50 value of 28.57 µg/mL. For anti-inflammatory activity, the A. splendens EO exhibited the highest potential with an IC50 value of 21.68 µg/mL, corresponding to an inhibition rate of NO production of 69.58 ± 1.3% and the percentage of cell life was 81.85 ± 0.9%.


Assuntos
Asarum , Óleos Voláteis , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Vietnã , Testes de Sensibilidade Microbiana , Antioxidantes/farmacologia
3.
J Appl Microbiol ; 132(2): 1025-1035, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34543506

RESUMO

AIMS: We investigated the antibacterial effect of seven essential oils (EOs) and one EO-containing liquid phytogenic solution marketed for poultry and pigs ('Product A') on chicken pathogens, as well as the relationship between minimum inhibitory concentration (MIC) in EOs and antibiotics commonly administered to chicken flocks in the Mekong Delta (Vietnam). METHODS AND RESULTS: Micellar extracts from oregano (Origanum vulgare), cajeput (Melaleuca leucadendra), garlic (Allium sativum), black pepper (Piper nigrum), peppermint (Mentha × piperita L.), tea tree (Melaleuca alternifolia), cinnamon (Cinnamomum zeylanicum) EOs and Product A were investigated for their MIC against Avibacterium endocarditidis (N = 10), Pasteurella multocida (N = 7), Ornitobacterium rhinotracheale (ORT) (N = 10), Escherichia coli (N = 10) and Gallibacterium anatis (N = 10). Cinnamon EO had the lowest median MIC across strains (median 0.5 mg/ml [IQR, interquartile range 0.3-2.0 mg/ml]), followed by Product A (3.8 mg/ml [1.9-3.8 mg/ml]), oregano EO (30.4 mg/ml [7.6-60.8 mg/ml]) and garlic 63.1 mg/ml [3.9 to >505.0 mg/ml]. Peppermint, tea tree, cajeput and pepper EOs had all MIC ≥219 mg/ml. In addition, we determined the MIC of the 12 most commonly used antibiotics in chicken flocks in the area. After accounting for pathogen species, we found an independent, statistically significant (p < 0.05) positive correlation between MIC of 10 of 28 (35.7%) pairs of EOs. For 67/96 (69.8%) combinations of EOs and antibiotics, the MICs were correlated. Of all antibiotics, doxycycline was positively associated with the highest number of EOs (peppermint, tea tree, black pepper and cajeput, all p < 0.05). For cinnamon, the MICs were negatively correlated with the MICs of 11/12 antimicrobial tested (all except colistin). CONCLUSIONS: Increases in MIC of antibiotics generally correlates with increased tolerance to EOs. For cinnamon EO, however, the opposite was observed. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results suggest increased antibacterial effects of EOs on multi-drug resistant pathogens; cinnamon EO was particularly effective against bacterial poultry pathogens.


Assuntos
Óleos Voláteis , Animais , Antibacterianos/farmacologia , Bactérias , Galinhas , Resistência Microbiana a Medicamentos , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Suínos
4.
Antimicrob Agents Chemother ; 65(12): e0027621, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34570647

RESUMO

The rise in Plasmodium falciparum resistance to dihydroartemisinin-piperaquine in Vietnam justifies the need to evaluate alternative artemisinin-based combination therapies. Between July 2018 and October 2019, a single-arm trial of pyronaridine-artesunate (Pyramax, PA) was conducted in Dak Nong province, Vietnam. PA (3-day course) was administered to adults and children infected with P. falciparum. PA was well tolerated by the participants. The proportion of patients with Day 42 PCR-corrected adequate clinical and parasitological response was 95.2% (95% confidence interval [CI], 82.3 to 98.8, n = 40/42) for treating falciparum malaria. The median parasite clearance half-life was 6.7 h (range, 2.6 to 11.9) and the median parasite clearance time was 72 h (range, 12 to 132) with 44.9% (22/49) of patients having positive blood films at 72 h. The two patients that recrudesced had comparable Day 7 blood pyronaridine concentrations (39.5 and 39.0 ng/ml) to the 40 patients who did not recrudesce (median 43.4 ng/ml, 95% CI, 35.1 to 54.9). Ring-stage and piperaquine survival assays revealed that of the 29 P. falciparum isolates collected from the patients before PA treatment, 22 (75.9%) had reduced susceptibility to artemisinins and 17 (58.6%) were resistant to piperaquine. Genotyping confirmed that 92.0% (46/50) of falciparum patients were infected with parasites bearing the Pfkelch13 C580Y mutation associated with artemisinin resistance. Of these, 56.0% (28/50) of the isolates also had multiple copies of the plasmepsin 2/3 genes responsible for piperaquine resistance. Overall, PA was effective in treating P. falciparum in the Central Highlands of Vietnam. (This study has been registered at AustralianClinicalTrials.gov.au under trial ID ACTRN12618001429246.).


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Quinolinas , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Artesunato , Combinação de Medicamentos , Humanos , Malária Falciparum/tratamento farmacológico , Naftiridinas , Plasmodium falciparum/genética , Quinolinas/uso terapêutico , Vietnã
5.
BMC Infect Dis ; 21(1): 523, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34082699

RESUMO

BACKGROUND: Vaginal candidiasis is frequent in women of reproductive age. Accurate identification Candida provides helpful information for successful therapy and epidemiology study; however, there are very limited data from the Vietnam have been reported. This study was performed to determine the prevalence, species distribution of yeast causing vaginal discharge and antifungal susceptibility patterns of Candida albicans among symptomatic non-pregnant women of reproductive age. METHODS: Vaginal discharge samples were collected from 462 women of reproductive age in Hanoi, Vietnam between Sep 2019 and Oct 2020. Vaginal swabs from these patients were examined by direct microscopic examination (10% KOH). CHROMagar™ Candida medium and Sabouraud dextrose agar supplemented with chloramphenicol (0.5 g/l) were used to isolate yeast, and species identification was performed using morphological tests and molecular tools (PCR and sequencing). Antifungal susceptibility testing was determined according to the Clinical and Laboratory Standards Institute guidelines (M27-A3 and M27-S4). RESULTS: The prevalence of vaginal yeast colonization in non-pregnant women was 51.3% of 462 participants. Nine different yeast species were identified. Among these isolates, C. albicans (51.37%) was the most frequent, followed by C. parapsilosis (25.88%), C. glabrata (11.37%), C. tropicalis (4.31%), C. krusei (3.92%), C. africana (1.57%), Saccharomyces cerevisiae (0.78%), C. nivariensis (1 isolates, 0.39%), and C. lusitaniae (1 isolates, 0.39%), respectively. Among C. albicans, all 46 isolates were 100% susceptible to micafungin, caspofungin, and miconazole. The susceptibility rates to amphotericine B, 5-flucytosine, fluconazole, itraconazole and voriconazole were 95.65, 91.30, 91.30, 82.61 and 86.95%, respectively. CONCLUSIONS: The prevalence of VVC among symptomatic non-pregnant women of reproductive age in Vietnam was higher than many parts of the world. The high frequency of non-albicans Candida species, which were often more resistant to antifungal agents, was a notable feature. Resistance rates of vaginal C. albicans isolates to antifungal agents was low. Our findings suggest that continued surveillance of changes in species distribution and susceptibility to antifungals should be routinely screened and treated.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candidíase Vulvovaginal/microbiologia , Descarga Vaginal/microbiologia , Adolescente , Adulto , Candida/classificação , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Candida albicans/classificação , Candida albicans/isolamento & purificação , Candidíase Vulvovaginal/epidemiologia , Farmacorresistência Fúngica/efeitos dos fármacos , Feminino , Humanos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Centros de Atenção Terciária , Descarga Vaginal/epidemiologia , Vietnã/epidemiologia , Adulto Jovem
6.
J Community Health ; 45(6): 1263-1269, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32894387

RESUMO

This study aimed to describe knowledge, attitudes, and practices (KAP) in controlling COVID-19 and some related factors among the Vietnamese population in 2020. A cross-sectional study was conducted involving 1999 participants aged 18-59 years old, through an online questionnaire. The results showed that 92.2% of the participants had a high knowledge level regarding COVID-19 prevention measures, 68.6% had a positive attitude toward COVID-19 prevention measures, and 75.8% practiced all six measures for preventing the spread of the virus. Age, sex, marital status, knowledge, and fear were significantly associated with the practices aimed at COVID-19 prevention. Married people and participants with high levels of knowledge were more likely to practice all preventive measures. In contrast, young people, men, and those who fear COVID-19 were less likely to practice all preventative measures. Good KAP among Vietnamese people could be an important factor in helping authorities gain initial success in containing the coronavirus and COVID-19. In addition to continuously raising and maintaining the community's awareness, attitude, and practices in disease prevention, the introduction and strict implementation of sanctions and regulations were also important in ensuring good practices were implemented and sustained over time. Groups with lower KAP levels should be provided with more information and support to promote appropriate disease prevention practices.


Assuntos
Controle de Doenças Transmissíveis , Infecções por Coronavirus/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Adolescente , Adulto , Betacoronavirus , COVID-19 , Estudos Transversais , Feminino , Humanos , Masculino , Estado Civil , Pessoa de Meia-Idade , SARS-CoV-2 , Inquéritos e Questionários , Vietnã , Adulto Jovem
7.
Food Control ; 107: 106756, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31902975

RESUMO

We investigated antimicrobial residues, non-typhoidal Salmonella (NTS), Vibrio spp. and their associated antimicrobial resistance (AMR), in shrimps locally purchased in Ho Chi Minh City (Vietnam). In addition, we investigated the relationship between AMR in NTS, Vibrio spp. and antimicrobial residue in the same sample. A total of 40 samples of shrimp heads/shells from different retail sources was cultured using ISO 6579-1:2017 (NTS) and ISO/TS 21872-1:2007 (Vibrio spp.). Phenotypic antimicrobial susceptibility was investigated using Vitek (NTS, 34 antimicrobials) and disk diffusion (Vibrio spp., 12 antimicrobials). A total of 9 (22.5%) samples contained antimicrobial residue, including tetracyclines, fluoroquinolones, sulfonamides and macrolides (in 7.5%, 7.5%, 2.5% and 2.5% of samples, respectively). Shrimp samples from supermarkets had a higher prevalence of antimicrobial residue than those purchased in street markets (50% vs. 13.3%) (p = 0.049). A total of 30 (75%) samples were contaminated with NTS. All samples contained Vibrio spp., with V. parahaemolyticus being most common (87.5% samples). A total of 58.9% NTS isolates were multidrug resistant. With regards to the highest priority, critically important antimicrobials, the highest resistance corresponded to quinolones (14.4-47.8%), followed by 3rd and 4th generation cephalosporins (3.3-7.8%). Vibrio spp. isolates were characterised by their high resistance against ampicillin (82.7%) and 3rd generation cephalosporins (8.3-16.5%). Extended Spectrum Beta-Lactamase (ESBL) activity was detected in 28.1% V. parahaemolyticus isolates. Half of ESBL-positive V. parahaemolyticus strains harboured bla CTX-M1. We found an association between the presence of residues and the number of resistances for NTS (p = 0.075) and Vibrio spp. isolates (p = 0.093) from the same sample. These findings suggest that the presence of residues may contribute to the selection of AMR in foodborne pathogens in shrimps. Authorities should strengthen policies aiming at restricting inappropriate antimicrobial usage in shrimp farming, and step up monitoring of antimicrobial residues and food-borne pathogens at retail in Vietnam.

8.
J Nanosci Nanotechnol ; 19(8): 5195-5204, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30913834

RESUMO

Synthesis of reduced graphene oxide/TiO2 nanotubes (rGO/TNTs) composite is being attended. However, the synthesis of rGO/TNTs composite directly from graphite oxide with a greener approach is still challenging. In this study, we directly synthesized rGO/TNTs composite by a simple method from graphite oxide and titanium dioxide nanotube (TNTs) powder without involving any assistant agents. The formation of the graphene oxide (GO) was confirmed by X-ray diffraction (XRD) pattern, transmission electron microscope (TEM) image, Fourier-transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Besides, photoluminescence analysis (PL) was conducted to determine the defects of materials. The methylene blue (MB) photodegradation efficiency under visible light of rGO/TNTs composite achieved 80% after 180 min. In addition, the key of the photocatalytic mechanism of rGO/TNTs under visible light was systematically investigated via trapping experiments.

9.
Sensors (Basel) ; 18(3)2018 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-29495411

RESUMO

Vital detection on the basis of Doppler radars has drawn a great deal of attention from researchers because of its high potential for applications in biomedicine, surveillance, and finding people alive under debris during natural hazards. In this research, the signal-to-noise ratio (SNR) of the remote vital-sign detection system is investigated. On the basis of different types of noise, such as phase noise, Gaussian noise, leakage noise between the transmitting and receiving antennae, and so on, the SNR of the system has first been examined. Then the research has focused on the investigation of the detection and false alarm probabilities of the system when the transmission link between the human and the radar sensor system took the Nakagami-m channel model. The analytical model for the false alarm and the detection probabilities of the system have been derived. The proposed theoretical models for the SNR and detection probability match with the simulation and measurement results. These theoretical models have the potential to be used as good references for the hardware development of the vital-sign detection radar sensor system.


Assuntos
Radar , Humanos , Modelos Teóricos , Ruído , Probabilidade , Razão Sinal-Ruído
10.
Eur J Nutr ; 56(1): 29-43, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26428672

RESUMO

PURPOSE: Over the past few decades, docosahexaenoic acid (DHA) has gained special attention for management of cholesterol-associated metabolic disorders and neurodegenerative diseases such as Alzheimer's disease (AD) owing to its neuroprotective, anti-inflammatory and hypolipidemic properties. Several epidemiological studies have reported the effect of DHA in reducing the risk of developing AD by lowering cholesterol. Hypercholesterolemia is a pro-amyloidogenic factor influencing the enzymatic processing of amyloid-ß precursor protein (AßPP) to toxic ß-amyloid. However, the mechanism by which DHA modulates the cholesterol pathway has not been established. Thus, the objective of this study was to investigate the mechanism of regulation of cholesterol metabolism by DHA in an AßPP695 overexpressing AD cell model. METHODS: A gas chromatography/mass spectrometry method was developed and validated for the targeted profiling of 11 cholesterol metabolites in DHA-treated Chinese hamster ovary wild-type (CHO-wt) and AßPP695 overexpressing (CHO-AßPP695) cells. The differential metabolite profiles between DHA- and vehicle-treated groups were further analyzed using fold change values of the ratio of concentration of metabolites in CHO-AßPP695 to CHO-wt cells. Effect of DHA on key rate-limiting enzymatic activities within the cholesterol pathway was established using biochemical assays. RESULTS: Our results showed that DHA reduced the levels of key cholesterol anabolites and catabolites in CHO-AßPP695 cells as compared to CHO-wt cells. Further enzymatic studies revealed that the cholesterol-lowering effect of DHA was mediated by regulating HMG-CoA reductase and squalene epoxidase enzyme activities. CONCLUSION: We demonstrate for the first time the dual effects of DHA in inhibiting HMG-CoA reductase and squalene epoxidase and modulating the sterol biosynthesis axis of the cholesterol pathway in AßPP695 overexpressing AD. Our novel findings underscore the potential of DHA as a multi-target hypocholesterolemic agent for the prophylaxis of AD and other cholesterol-associated diseases.


Assuntos
Anticolesterolemiantes/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Metabolismo dos Lipídeos/efeitos dos fármacos , Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Células CHO , Linhagem Celular , Cricetinae , Cricetulus , Hidroximetilglutaril-CoA Redutases/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Esqualeno Mono-Oxigenase/antagonistas & inibidores , Esqualeno Mono-Oxigenase/metabolismo , Esteróis/metabolismo
11.
World Neurosurg ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38762026

RESUMO

OBJECTIVE: The purpose of this report is to describe a case series of children undergoing selective dorsal rhizotomy (SDR) for the treatment of spastic cerebral palsy in Vietnam. Also described is an international cooperation model to facilitate the development of a new, multidisciplinary team for the evaluation and treatment of these children. METHODS: Details of international collaboration are described, including in-person travel and virtual interactions. All cases of children younger than 18 years undergoing SDR for treatment of spastic cerebral palsy at a single center in Hanoi, Vietnam are described, including preoperative evaluation of spasticity and gait as well as results at 6 and 12 months. Results are summarized using descriptive statistics. RESULTS: Since the beginning of cooperation in training and transferring SDR techniques by experts from the United States, in the period from June 2016 to December 2022, 18 SDR surgeries were performed in Hanoi. Patients' ages ranged from 2 to 14 years; 13 were male and 5 were female. Overall, approximately 60% of nerve rootlets were cut. Modified Ashworth Scale scores at 6 and 12 months after surgery in the hip, knee, and ankle joints showed improvement from preoperative values. There were 2 recorded complications: intracranial hypotension causing subdural hemorrhage and a case of skin infection at the incision site. CONCLUSIONS: The ongoing international cooperation between Vietnamese and American physicians has helped improve the surgical treatment of spasticity in children with cerebral palsy in Hanoi, providing children with a surgical treatment option with successful outcomes.

12.
Commun Agric Appl Biol Sci ; 78(4): 320-3, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25141701

RESUMO

A project for intensive culture of Artemia in Vinhchau solar saltwork was funded by Soctrang Authority. The aim of this project is to increase the average cyst yield of 50kg.ha-1.crop, and to build up a stable culture technique with a better yield for local farmers. Multiple laboratory experiments were set up with inert food including fermented rice bran, tiger shrimp feed (PL15), as well as their combination with live algae (Chaetoceros). Results showed that, under laboratory conditions, fermented rice bran and tiger shrimp feed can be used as supplemental food sources. The shrimp feed alone or in combination with algae always gave better cyst production compared to the others, but should not account for more than 50% of the diet. In the field trials, aeration of Artemia ponds also increased cyst yields (from 195.8+/-44.2 to 207+/-46.1kg.ha-1.crop with 6 and 12 aeration a day, respectively) compared to ponds with no aeration (88.2+/-27.5kg.ha-1.crop), however the returns on investment (ROI=2.73-2.71 with aera tion vs. 2.24 without) are not significantly different. Utilization of fermented rice bran (20kg.ha-1.day) and shrimp feed (6kg.ha-1.day) as a supplementary feed during pond production in combination with greenwater supplies (10% of pond volume daily) resulted in higher yields (96.0+/-15.9 and 157.2+/-15.0kg.ha-1.crop, respectively) than traditional culture; Shrimp feed as a supplemental feed supported the cyst yield but their negative effect was at a high cost vs. traditional culture and use of fermented rice bran. Based on the cyst yield and ROI, fermented rice bran should be a promising item for poor farmers.


Assuntos
Ração Animal/análise , Aquicultura/métodos , Artemia/crescimento & desenvolvimento , Ração Animal/economia , Animais , Aquicultura/economia , Artemia/efeitos dos fármacos , Povo Asiático , Dieta/veterinária , Relação Dose-Resposta a Droga , Humanos , Lagoas/química , Reprodução
13.
RSC Adv ; 13(32): 21838-21849, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37475759

RESUMO

We herein present a simple, fast, efficient and environmentally friendly method for preparing silver nanoparticles (AgNPs) using the solution plasma method in the presence of extracts from Paramignya trimera (P. trimera). The effects of P. trimera extract concentrations and the applied voltage on the formation of AgNPs were investigated. Surface plasmon resonance spectra show a strong peak at 413 nm for the prepared samples. The Fourier-transform infrared spectroscopy measurement results indicated the presence of possible functional groups in the prepared AgNPs. Morphological analysis revealed that the AgNPs were spherical with an average size of 8 nm. The prepared AgNPs exhibited good stability in solution compared to that of AgNPs prepared by the solution plasma technique without P. trimera extract. The formation mechanism of AgNPs is also proposed. The prepared AgNPs exhibited high antibacterial ability against Gram (+) Staphylococcus aureus, Gram (-) Pseudomonas aeruginosa bacteria and strong anticancer activity for the AGS gastric cancer cell line. The obtained results demonstrated that this is a simple, rapid, environmentally friendly method for preparing AgNPs instead of conventional methods using chemical reducing agents for potential applications.

14.
Chem Commun (Camb) ; 59(14): 1947-1950, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36637415

RESUMO

A practical strategy for the iodine-promoted synthesis of bis(1-imidazo[1,5-a]pyridyl)arylmethane and its derivatives has been developed. These compounds exhibit high cytotoxicity toward various cancer cell lines and moreover they are promising ligands for the Cu-catalysed synthesis of quinolines.

15.
ACS Org Inorg Au ; 3(3): 151-157, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37303502

RESUMO

Regioselective phosphonation of pyridines is an interesting transformation in synthesis and medicinal chemistry. We report herein a metal-free approach enabling access to various 4-phosphonated pyridines. The method consists of simply activating the pyridine ring with a Lewis acid (BF3·OEt2) to facilitate the nucleophilic addition of a phosphine oxide anion. The formed sigma complex is subsequently oxidized with an organic oxidant (chloranil) to yield the desired adducts in good to excellent yields. We furthermore showed that access to C2-phosphoinated pyridines can be achieved in certain cases with strong Lewis basic phosphorus nucleophiles or with strong Lewis acidic pyridines. Both experimental and computational mechanistic investigations were undertaken and allowed us to understand the factors controlling the reactivity and selectivity of this reaction.

16.
Lancet Reg Health West Pac ; 30: 100668, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36748068

RESUMO

Background: Drug outlets are a vital first point of healthcare contact in low- and middle-income countries (LMICs), but they are often poorly regulated and counter staff may be unqualified to provide advice. This introduces the risk of easy access to potentially harmful products, including unnecessary antimicrobials. Over-the-counter antimicrobial sales are a major driver of antimicrobial resistance (AMR) in LMICs. We aimed to investigate the distribution of different types of drug outlets and their association with socio-economic factors. Methods: We mapped the location of drug outlets in 40 randomly selected geographic clusters, covering a population of 1.96 million people. Data including type of drug outlet, context, operating hours, chief pharmacist name and qualification, and business registration identification were collected from mandatory public signage. We describe the density of drug outlets and levels of staff qualifications in relation to population density, urban vs rural areas, and poverty indices. Findings: We characterised 1972 drug outlets. In the study area, there was an average of 102 outlets/per 100,000 population, compared to the global average of 25. Predictably, population density was correlated with the density of drug outlets. We found that drug outlets were less accessible in rural vs urban areas, and for the poor. Furthermore, for these populations, degree-qualified pharmacists were less accessible and public signage frequently lacked mandatory registration information. Interpretation: Drug outlets appear over-supplied in Vietnam compared to other countries. Unregistered outlets and outlets without degree-qualified pharmacists are prevalent, especially in poor and rural areas, posing a risk for inappropriate supply of antimicrobials, which may contribute to AMR, and raises questions of equitable healthcare access. Funding: This study was funded by a grant from the Australian Department of Foreign Affairs and Trade.

17.
RSC Adv ; 12(30): 19225-19231, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35865612

RESUMO

Aerogel cellulose materials were synthesised from Water hyacinth and different crosslinkers, such as kymene and a mixture of polyvinyl alcohol (PVA) and glutaraldehyde (GA). The effects of using a magnetic stirrer and ultrasonic methods were investigated. The results show that materials prepared using ultrasonic methods have higher porosity and lower density. The thermal conductivity of the synthesised aerogel cellulose could be as low as 0.0281 W m K-1, showing the good heat insulation performance of this material. Absorption capacity was tested using diesel oil (DO), and the highest capacities of 58.82 and 52.03 g g-1 of DO were found with kymene and PVA + GA as crosslinkers, respectively. The reusability of the materials was tested. After 10 cycles, the DO absorption capacity was 62.8% of the value of the first cycle for the aerogel cellulose sample with kymene as the crosslinker and 72.7% for the sample with PVA + GA as the crosslinking agent.

18.
Chemosphere ; 307(Pt 3): 135834, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35963379

RESUMO

Each year, Asia produces an estimated 350 million tonnes of agricultural residues. According to Ministry of Power projections, numerous tonnes of such waste are discarded each year, in addition to being used as green manure. The methodology used to convert agricultural waste into the most valuable biochar, as well as its critical physical and chemical properties, were described in this review. This review also investigates the beneficial effects of bio and phytoremediation on metal(lloid)-contaminated soil. Agriculture biomass-based biochar is an intriguing organic residue material with the potential to be used as a responsible solution for metal(lloid) polluted soil remediation and soil improvement. Plants with faster growth and higher biomass can meet massive remediation demands. Recent research shows significant progress in agricultural biomass-based biomass conversion as biochar, as well as understanding the frameworks of metal(lloid) accumulation and mobility in plants used for metal(lloid) polluted soil remediation. Biochar made from various agricultural biomass can promote native plant growth and improve phytoremediation efficiency in polluted soil with metal(lloid)s. This carbon-enriched biochar promotes native microbial activity by neutralising pH and providing adequate nutrition. Thus, this review critically examines the feasibility of converting agricultural waste biomass into biochar, as well as the impact on plant and microbe remediation potential in metal(lloid)s polluted soil.


Assuntos
Esterco , Poluentes do Solo , Agricultura , Biodegradação Ambiental , Biomassa , Carvão Vegetal/química , Metais , Plantas , Solo/química , Poluentes do Solo/química
19.
Iran J Parasitol ; 17(1): 1-9, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36046560

RESUMO

Background: We determined the occurrence frequency of Clinical signs, subclinical characteristics on positive anti-IgG Toxocara ELISA cases, and clinical response results after 1 month of albendazole-specific treatment. Methods: A number of 103 clinically treated patients were studied between 2018 and 2019 in two hospitals. Relevant data are collected from examination and medical records such as age, sex, job, resident, clinical and sub-clinical signs. Sera samples were subjected to anti-IgG Toxocara antigen using ELISA. Results: The median age of the patient was 43.6 ± 14.4 years. The most common symptom groups were the skin and mucosa (88.3%), followed by neurological symptoms (44%). There are 76.7% of patients with risk factors for contact with pet dogs and cats. The majority of eosinophils in the normal range (< 8%) accounted for 85.4%, the major results of the OD value of ELISA were in the group (≥ 0.3-< 1.5) accounted for 75.7%. The skin and mucosa lesions in toxocariasis patients related to IgE values were statistically significant (P <0.05). The effectiveness of anthelmintic treatment is low with nearly half of patients having no clinical symptoms after 1 month of post-treatment. It is statistically significant between exposure to dogs/cats and treatment outcomes on clinical symptoms (P < 0.05). Conclusion: Toxocara infections in Vietnamese people often have skin allergies and liver damage, rarely with severe neurological symptoms. The efficacy of albendazole treatment after one month is not clear. In the near future, research with a confirmatory test other than Anti-IgG Toxocara ELISA is needed to screen for inhospital diagnosis.

20.
JAC Antimicrob Resist ; 4(2): dlac038, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35449721

RESUMO

Background: Vietnam and Southeast Asia are hotspots for antimicrobial resistance; however, little is known on the prevalence of carriage of carbapenem resistance in non-hospitalized humans and in animals. Carbapenem-resistant Enterobacteriaceae (CRE), particularly Escherichia coli (CREC) and Klebsiella pneumoniae (CRKP) and also Acinetobacter baumannii (CRAB) are emerging threats worldwide. Methods: We investigated healthy humans (n = 652), chickens (n = 237), ducks (n = 150) and pigs (n = 143) in 400 small-scale farms in the Mekong Delta of Vietnam. Samples (rectal swabs, faecal swabs) were investigated for carriage of CRE/CRAB and were further characterized phenotypically and genotypically. Results: In the Mekong Delta of Vietnam, the prevalence of CRE isolates in human rectal swabs was 0.6%, including 4 CREC and 1 CRKP. One pig was infected with CREC (prevalence 0.7%). CRAB was isolated from chickens (n = 4) (prevalence 2.1%) and one duck (prevalence 0.7%). CRKP was isolated from a human who was also colonized with CREC. The CRKP strain (ST16), from an 80 year-old person with pneumonia under antimicrobial treatment, genetically clustered with clinical strains isolated in a hospital outbreak in southern Vietnam. The prevalence of CRE was higher among humans that had used antimicrobials within 90 days of the sampling date than those had not (4.2% versus 0.2%) (P = 0.005). All CRE/CRAB strains were MDR, although they were susceptible to colistin and neomycin. The carbapenemase genes identified in study strains were bla NDM and bla OXA. Conclusions: The finding of a CRKP strain clustering with previous hospital outbreak raises concerns about potential transmission of carbapenem-resistant organisms from hospital to community settings or vice-versa.

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