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1.
BMC Cancer ; 24(1): 176, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317094

RESUMO

BACKGROUND: This study aimed to evaluate the efficacy and side effects of first-line afatinib treatment in a real-world setting in Vietnam. METHODS: This retrospective study was conducted across nine hospitals in Vietnam. Advanced epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) patients who received afatinib as first-line therapy between April 2018 and June 2022 were included, and patient medical records were reviewed. Key outcomes were overall response rate (ORR), time-to-treatment failure (TTF), and tolerability. RESULTS: A total of 343 patients on first-line afatinib were eligible for the study. EGFR exon 19 deletion (Del19) alone was detected in 46.9% of patients, L858R mutation alone in 26.3%, and other uncommon EGFR mutations, including compound mutations, in 26.8%. Patients with brain metastases at baseline were 25.4%. Patients who received 40 mg, 30 mg, and 20 mg as starting doses of afatinib were 58.6%, 39.9%, and 1.5%, respectively. The ORR was 78.1% in the overall population, 82.6% in the Del19 mutation subgroup, 73.3% in the L858R mutation subgroup, and 75.0% in the uncommon mutation subgroup (p > 0.05). The univariate and multivariate analyses indicate that the ORR increased when the starting dose was 40 mg compared to starting doses below 40 mg (83.9% vs. 74.3%, p = 0.034). The median TTF (mTTF) was 16.7 months (CI 95%: 14.8-18.5) in all patients, with a median follow-up time of 26.2 months. The mTTF was longer in patients in the common EGFR mutation subgroup (Del19/L858R) than in those in the uncommon mutation subgroup (17.5 vs. 13.8 months, p = 0.045) and in those without versus with brain metastases at baseline (17.5 vs. 15.1 months, p = 0.049). There were no significant differences in the mTTF between subgroups based on the starting dose of 40 mg and < 40 mg (16.7 vs. 16.9 months, p > 0.05). The most common treatment-related adverse events (any grade/grade ≥ 3) were diarrhea (55.4%/3.5%), rash (51.9%/3.2%), paronychia (35.3%/5.0%), and stomatitis (22.2%/1.2%). CONCLUSIONS: Afatinib demonstrated clinical effectiveness and good tolerability in Vietnamese EGFR-mutant NSCLC patients. In our real-world setting, administering a starting dose below 40 mg might result in a reduction in ORR; however, it might not have a significant impact on TTF.


Assuntos
Afatinib , Neoplasias Encefálicas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Afatinib/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Estudos de Coortes , Receptores ErbB/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos , Vietnã/epidemiologia
2.
Nanotechnology ; 34(24)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-36881902

RESUMO

Construction of various nanostructures with nanometre-scale precision through various DNA building blocks depends upon self-assembly, base-pair complementarity and sequence programmability. During annealing, unit tiles are formed by the complementarity of base pairs in each strand. Enhancement of growth of target lattices is expected if seed lattices (i.e. boundaries for growth of target lattices) are initially present in a test tube during annealing. Although most processes for annealing DNA nanostructures adopt a one-step high temperature method, multi-step annealing provides certain advantages such as reusability of unit tiles and tuneability of lattice formation. We can construct target lattices effectively (through multi-step annealing) and efficiently (via boundaries) by multi-step annealing and combining boundaries. Here, we construct efficient boundaries made of single, double, and triple double-crossover DNA tiles for growth of DNA lattices. Two unit double-crossover DNA tile-based lattices and copy-logic implemented algorithmic lattices were introduced to test the growth of target lattices on boundaries. We used multi-step annealing to tune the formation of DNA crystals during fabrication of DNA crystals comprised of boundaries and target lattices. The formation of target DNA lattices was visualized using atomic force microscopy (AFM). The borders between boundaries and lattices in a single crystal were clearly differentiable from AFM images. Our method provides way to construct various types of lattices in a single crystal, which might generate various patterns and enhance the information capacity in a given crystal.


Assuntos
DNA , Nanoestruturas , Conformação de Ácido Nucleico , DNA/química , Microscopia de Força Atômica , Nanoestruturas/química , Nanotecnologia/métodos
3.
J Fluoresc ; 33(4): 1359-1366, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36695956

RESUMO

Herein, dual-emission carbon dots (DE-CDs) were synthesized using a one-pot hydrothermal method. DE-CDs exhibited two well-separated peaks at 433 and 513 nm under ultraviolet excitation. The prepared DE-CDs offer selective detection of Fe3+ ions via inner filter effect (IFE) and Pb2+ ions via aggregation-induced enhancement (AIE). The obtained DE-CDs showed a good affinity for both Fe3+ and Pb2+ ions in the presence of various interfering ions. The limits of detection were 0.797 ppm and 4.739 ppm for Pb2+ and Fe3+, respectively. The finding reveals the huge potential of DE-CDs for the selective detection of multiple targets in one solution.

4.
Phys Chem Chem Phys ; 25(47): 32569-32577, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37999640

RESUMO

In this work, the stability, and electronic and magnetic properties of pristine and doped graphene-like ionic NaX (X = F and Cl) monolayers are explored using first-principles calculations. The good stability of NaF and NaCl monolayers is confirmed by phonon dispersion curves and ab initio molecular dynamics simulations. Electronic structure calculations show their insulator nature with large indirect band gaps of 5.43 (7.26) and 5.06 (6.32) eV as calculated with the PBE (HSE06) functional, respectively. In addition, their ionic character is also demonstrated. Furthermore, a doping approach is explored to functionalize NaX monolayers for spintronic applications. For such a goal, IIA- and VIA-group atoms are selected as dopants due to their dissimilar valence electronic configuration as compared with the host atoms. The results indicate the emergence of magnetic semiconductor nature with a total magnetic moment of 1µB. Herein, magnetic properties are produced mainly by the dopant atoms, which induce new middle-gap energy states around the Fermi level. Finally, the effects of codoping the NaF monolayer with Ca and O and NaCl with Ba and O are also examined. Adjacent Ca-O and Ba-O pairs preserve the non-magnetic nature. Further separating dopants leads to the emergence of magnetic semiconductor behavior, with lower magnetization than separate doping. This work introduces new ionic 2D materials for optoelectronic and spintronic applications, contributing to the research effort to find out new 2D multifunctional materials.

5.
Phys Chem Chem Phys ; 25(20): 14502-14510, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37190945

RESUMO

Seamlessly stitching two-dimensional (2D) materials may lead to the emergence of novel properties triggered by the interactions at the interface. In this work, a series of 2D lateral heterostructures (LHSs), namely germanene-arsenene (Gem-As8-m) and germanene-antimonene (Gem-Sb8-m), are investigated using first-principles calculations. The results demonstrate a strong interline-dependence of the electronic and magnetic properties. Specifically, the LHS formation along an armchair line preserves the non-magnetic nature of the original materials. However, this is an efficient approach to open the electronic band gap of the germanene monolayer, where band gaps as large as 0.74 and 0.76 eV are induced for Ge2-As6 and Ge2-Sb6 LHSs, respectively. Meanwhile, magnetism may appear in the zigzag-LHSs depending on the chemical composition (m = 3, 4, 5, and 6 for germanene-arsenene and m = 2, 3, 4, 5, and 6 for germanene-antimonene), where total magnetic moments between 0.13 and 0.50 µB are obtained. Herein, magnetic properties are produced mainly by the spin-up state of Ge atoms at the interface, where a small contribution comes from As(Sb) atoms. Spin-resolved band structures show a multivalley profile in both the valence band and the conduction band with a topological insulator-like behavior, where the interface states are derived mainly from the interface Ge-pz state. The results introduce new 2D lateral heterostructures with novel electronic and magnetic properties to allow new functionalities, which could be further explored for optoelectronic and spintronic applications.

6.
Phytopathology ; 113(8): 1605-1614, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37019906

RESUMO

Passiflora mottle virus (PaMoV), an aphid-borne potyvirus, is the primary causal virus of devastating passionfruit woodiness disease in Vietnam. Here we generated a nonpathogenic, attenuated PaMoV strain for disease control by cross protection. A full-length genomic cDNA of PaMoV strain DN4 from Vietnam was constructed to generate an infectious clone. The green fluorescent protein was tagged at the N-terminal region of the coat protein gene to monitor in planta the severe PaMoV-DN4. Two amino acids within the conserved motifs of helper component protease (HC-Pro) of PaMoV-DN4 were mutated individually or in combination as K53E or/and R181I. Mutants PaMoV-E53 and PaMoV-I181 induced local lesions in Chenopodium quinoa plants, while PaMoV-E53I181 caused infection without apparent symptoms. In passionfruit (Passiflora edulis) plants, PaMoV-E53 elicited severe leaf mosaic and PaMoV-I181 induced leaf mottling, while PaMoV-E53I181 caused transient mottling followed by symptomless recovery. PaMoV-E53I181 was stable after six serial passages in yellow passionfruit (Passiflora edulis f. flavicarpa) plants. Its temporal accumulation levels were lower than those of the wild type, with a zigzag accumulation pattern, typical of a beneficial protective virus. An RNA silencing suppression (RSS) assay revealed that all three mutated HC-Pros are defective in RSS. Triplicated cross-protection experiments with a total of 45 plants showed that the attenuated mutant PaMoV-E53I181 provided a high protection rate (91%) against the homologous wild-type virus in passionfruit plants. This work revealed that PaMoV-E53I181 can be used as a protective virus to control PaMoV by cross protection.

7.
Arch Environ Contam Toxicol ; 85(3): 290-301, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37515646

RESUMO

Pesticide residues are regularly found in surface water, which could be dangerous for freshwater ecosystems and biodiversity. Pesticides may enter waters through a variety of pathways, but runoff from irrigation or precipitation has the highest quantities. Previous studies analyzing the pesticides pollution or ecological risks of pesticides focused on few regions (e.g., European and United States), whereas analysis of pesticide pollution in Southeast Asia and especially in Vietnam is limited. This study presents an investigation of banned pesticides used across the range of land use in catchments of the Ma river and its tributaries in Thanh Hoa province, Vietnam. Applying principal component analysis (PCA), we investigated the relationship between specific pesticides and land use. Besides, cluster analysis (CA), the method of aggregating monitoring locations, was applied in this study to find spatial pattern of pesticides pollution. Due to their persistence and remobilization during floods and runoff, all ten banned pesticides-eight insecticides (aldrin/dieldrin, BHC, chlordane, endrin, heptachlor, lindane, malathion, and parathion) and two herbicides (paraquat, and 2,4D)-still remain in surface water and are not presumably influenced by the fraction of land use area in the catchments. Clustering results revealed that banned pesticides still occur in some areas. Site TH08 close to Le Mon industrial zone and TH18 in Thanh Hoa city have higher concentrations of banned pesticides than other sites due to their highly toxic and long-time existence in the environment. Overall, our study provides approach to investigate pesticides in surface water for a province in Vietnam that may be used for future ecotoxicological studies to enhance risk assessment for stream ecosystems.


Assuntos
Praguicidas , Poluentes Químicos da Água , Praguicidas/análise , Rios/química , Vietnã , Água/análise , Ecossistema , Poluentes Químicos da Água/análise , Monitoramento Ambiental
8.
J Appl Microbiol ; 132(4): 3217-3225, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35119770

RESUMO

AIMS: This study aimed to improve the viability of probiotic bacteria during freeze-drying by the combination of self-encapsulation and cryoprotectants. METHODS AND RESULTS: Lactiplantibacillus plantarum VAL6 and Lactobacillus acidophilus VAR1 were exposed to environmental stresses including temperature, pH and increased CO2 concentration before performing freeze-drying with the addition of cryoprotectants. The results proved that tested stresses can stimulate the bacteria to synthesize more extracellular polymeric substances to form self-encapsulation that increases their freeze-dried viability. In combination with cryoprotectants to form double-layered microencapsulation, L. plantarum VAL6 stressed at pH 3.5 in combination with whey protein isolate could achieve the highest Improving Cell Viability of 4361-fold, while L. acidophilus VAR1 stressed at 25o C in combination with alginate gave a maximum Improving Cell Viability of 73.33-fold. CONCLUSIONS: The combination of self-encapsulation and cryoprotectants significantly improves the freeze-dried viability of probiotics. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report that uses environmental stress to stimulate extracellular polymeric substance synthesis for self-encapsulation formation combined with the addition of cryoprotectants to enhance the freeze-dried survival of probiotics. This could be a novel approach in improving the viability of probiotic strains for various applications.


Assuntos
Matriz Extracelular de Substâncias Poliméricas , Probióticos , Crioprotetores/farmacologia , Liofilização , Lactobacillus acidophilus , Viabilidade Microbiana
9.
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
10.
Curr Microbiol ; 79(6): 165, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35445852

RESUMO

To demonstrate that the amount of extracellular polymeric substances (EPS) and the freeze-dried viability of probiotics are correlated. Three strains of probiotics including Lactiplantibacillus plantarum, Lactobacillus acidophilus, and Bifidobacterium bifidum were subjected to environmental challenges, such as temperature, pH, and carbon dioxide. The results indicated that the challenges could stimulate the EPS synthesis of the probiotics. The experimental correlation between the amount of synthesized EPS and the freeze-dried survival rate was also analyzed, and the viability of each of the three strains was represented by the following functions in which the equation of L. plantarum is y = - 0.0336x2 + 2.7059x - 14.849 with R2 = 0.9699, the B. bifidum's equation is y = - 0.0554x2 + 2.6243x - 13.654 with R2 = 0.9554, and the L. acidophilus's one was y = 0.0346x2 + 0.5862x - 9.1339 with R2 = 0.9733. This could be a new approach to determining the freeze-dried viability of probiotic strains based on the measured EPS content.


Assuntos
Matriz Extracelular de Substâncias Poliméricas , Probióticos , Liofilização , Lactobacillus acidophilus , Taxa de Sobrevida
11.
Phytopathology ; 111(9): 1675-1685, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33487021

RESUMO

Passionfruit plantings in Vietnam increased to 10,000 ha in 2019. However, outbreaks of passionfruit woodiness disease (PWD) have become a serious threat to production. In this study, five virus isolates (DN1, DN4, NA1, GL1, and GL2) were collected from different areas of Vietnam. Their causal roles in PWD were verified by back-inoculation to passionfruit. Analyses of coat protein (CP) and genomic sequences revealed that the GL1 isolate is closely related to East Asia Passiflora virus (EAPV) AO strain of Japan (polyprotein nt and aa identities of 98.1 and 98.2%, respectively), and the GL2 isolate is related to Telosma mosaic virus (TelMV) isolate PasFru, China (polyprotein nt and aa identities of 87.1 and 90.9%, respectively). CP comparison, host range, and cytological characterization indicated that DN1, DN4, and NA1 are potyviruses but are different from EAPV and TelMV. Phylogenic analyses of their CP and genome sequences indicated that these three isolates and the passionfruit severe mottle-associated virus Fujian isolate of China belong to a distinct clade, which does not meet the threshold (76% nt identity of polyprotein) to be regarded as any of potyviral species. Thus, a new species name, Passiflora mottle virus, (PaMoV), has been proposed by the International Committee on Taxonomy of Viruses. A rabbit antiserum was produced against the CP of DN1, and it can distinguish PaMoV from TelMV and EAPV in western blotting and enzyme-linked immunosorbent assay (ELISA) without cross-reactions. Field surveys of 240 samples by ELISA and reverse transcription PCR found that PWD in Vietnam is caused mainly by PaMoV, followed by EAPV, mixed infection of PaMoV and EAPV, and rare cases of TelMV.


Assuntos
Passiflora , Potyvirus , Animais , China , Doenças das Plantas , Potyvirus/genética , Coelhos , Vietnã
12.
J Environ Manage ; 296: 113364, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34399553

RESUMO

The purpose of this study is to address the criticism that corporate environmental activities to meet the UN sustainable development goals (SDGs) are simply greenwashing. To this end, we clarify whether and why corporate environmental activities are effective in achieving SDGs from the stakeholder management perspective. Using data on Vietnamese companies, we first empirically clarify the influence of stakeholder pressure on a company's environmental management control system (EMCS) implementation as a comprehensive approach to environmental activities and maintaining a proactive attitude toward the SDGs. Second, we examine the influence of EMCS implementation on environmental performance with or without proactive attitudes. The main findings are as follows. Companies implementing EMCSs normally improve their environmental performance, and pressure from final consumers and the government is a precondition for this accomplishment. However, if these companies incorporate the SDGs into their business targets, they can actually improve their environmental performance somewhat further, and government pressure plays an important role in this additional accomplishment. Therefore, corporate environmental activities to meet the SDGs work better than existing activities in Vietnam, refuting the criticism of greenwashing. Importantly, the Vietnamese government as a powerful stakeholder has proactively promoted domestic structural change to achieve the SDGs and has enacted many policies to encourage companies to be proactive in their environmental activities.


Assuntos
Objetivos , Desenvolvimento Sustentável , Povo Asiático , Governo , Humanos , Organizações
13.
Molecules ; 26(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209621

RESUMO

Silica nanoparticles (SiO2 NPs) synthesized by the Stober method were used as drug delivery vehicles. Doxorubicin hydrochloride (DOX·HCl) is a chemo-drug absorbed onto the SiO2 NPs surfaces. The DOX·HCl loading onto and release from the SiO2 NPs was monitored via UV-VIS and fluorescence spectra. Alternatively, the zeta potential was also used to monitor and evaluate the DOX·HCl loading process. The results showed that nearly 98% of DOX·HCl was effectively loaded onto the SiO2 NPs' surfaces by electrostatic interaction. The pH-dependence of the process wherein DOX·HCl release out of DOX·HCl-SiO2 NPs was investigated as well. For comparison, both the free DOX·HCl molecules and DOX·HCl-SiO2 NPs were used as the labels for cultured cancer cells. Confocal laser scanning microscopy images showed that the DOX·HCl-SiO2 NPs were better delivered to cancer cells which are more acidic than healthy cells. We propose that engineered DOX·HCl-SiO2 systems are good candidates for drug delivery and clinical applications.


Assuntos
Antineoplásicos , Doxorrubicina , Portadores de Fármacos , Nanopartículas , Neoplasias , Dióxido de Silício , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Humanos , Células MCF-7 , Microscopia Confocal , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Dióxido de Silício/química , Dióxido de Silício/farmacocinética , Dióxido de Silício/farmacologia
14.
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.

15.
BMC Infect Dis ; 19(1): 347, 2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-31029099

RESUMO

BACKGROUND: Pooling sputum specimens is one potential strategy for reducing the cost of using Xpert MTB/RIF, a rapid polymerase chain reaction (PCR)-based test, for the diagnosis of pulmonary tuberculosis. We sought to compare the sensitivity of two alternative method of pooling. METHODS: Patients referred for assessment for TB, whose initial sputum was Xpert MTB positive, were recruited and their sputum specimens were pooled for analysis with sputum specimens that were Xpert MTB negative. Two alternative pooling strategies were employed: one in which the concentration of sample reagent (buffer) was maintained at 2:1 (standard), in accordance with the manufacturer's instructions, and another in which the concentration of sample reagent was reduced to 1:1. RESULTS: We tested 101 Xpert MTB positive sputum specimens. Among these, 96% of valid test results (95% confidence interval (CI) 89-99%) were positive using the "standard buffer method". Using the "reduced buffer pooling" method 94% of valid test results (95% CI 87-98%) were positive. McNemar's test for the difference in paired proportions did not reach statistical significance (P = 0.56). CONCLUSION: We have confirmed that pooling of two sputum specimens for testing in a single cartridge is a valid method of reducing the number of cartridges required when using Xpert MTB to detect pulmonary tuberculosis. Two alternative pooling strategies tested here yielded similar results. TRIAL REGISTRATION: The present study was conducted within the Active Casefinding in Tuberculosis (ACT3) Trial. The ACT3 Trial had been registered with Australian and New Zealand Clinical Trials Register on 8th April, 2014. The trial registration number is ACTRN12614000372684 . (Retrospectively registered).


Assuntos
Mycobacterium tuberculosis/genética , Escarro/microbiologia , Tuberculose/diagnóstico , Estudos Transversais , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Humanos , Mycobacterium tuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade
16.
Biosci Biotechnol Biochem ; 83(12): 2177-2182, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31448683

RESUMO

Three new flavonol glycosides, fissflavosides A-C (1-3), together with six known flavonol glycosides, kaempferol 3-O-α-L-rhamnopyranosyl-(1→2)-ß-D-galactopyranoside (4), kaempferol 3-O-α-L-rhamnopyranosyl-(1→6)-ß-D-galactopyranoside (5), kaempferol 3-O-α-L-rhamnopyranosyl-(1→6)-ß-D-glucopyranoside (6), rhamnetin 3-O-α-L-rhamnopyranosyl-(1→2)-ß-D-glucopyranoside (7), rutin (8), and isorhamnetin 3-O-α-L-rhamnopyranosyl-(1→2)-ß-D-galactopyranoside (9) were isolated from the methanol extract of the Fissistigma pallens leaves. Their chemical structures were determined by 1D-, 2D-NMR, and MS data as well as in comparison with reported data in the literature. Compounds 1-9 showed weak cytotoxic activity on three human cancer cell lines, HT-29, A-2058, A-549 with IC50 ranging from 134.6 to 162.6 µM. In addition, the antioxidant capacities of compounds were also tested by ORAC assay. All compounds showed significant antioxidant with trolox equivalents ranging from 4.4 to 8.6 µM at the concentration of 1.0 µM. The results indicated 7 and 8 having meaningful reducing capacity of copper (I) ions of 2.7 to 6.9 µM at the concentrations of 1 and 2 µM.


Assuntos
Annonaceae/química , Flavonóis/química , Glicosídeos/isolamento & purificação , Antioxidantes/farmacologia , Configuração de Carboidratos , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/química , Glicosídeos/farmacologia , Humanos , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
17.
Molecules ; 23(12)2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30567316

RESUMO

Nanogel-based systems loaded with single anticancer drugs display miscellaneous effectiveness in tumor remission, gradually circumventing mutation and resistance in chemotherapy. Hence, the existence of dual-drug delivered nano-sized systems has been contemporaneous with drug development and preceded the conventional-dose chemotherapy. Among outstanding synergistic drug nanoplatforms, thermosensitive copolymer heparin-Pluronic F127 (Hep-F127) co-delivering cisplatin (CDDP) and curcumins (Cur) (Hep-F127/CDDP/Cur) has emerged as a notable candidate for temperature-responsive drug delivery. The procedure was based on the entrapment of curcumin into the hydrophobic core of bio-degradable co-polymer Hep-F127 while the hydrophilic drug CDDP subsequently conjugated to the backbone heparin to form the core-shell structure. The copolymer was characterized by Fourier transform infrared (FT-IR) spectrophotometry, Transmission Electron Microscopy (TEM), and Dynamic Light Scattering (DLS), to corroborate the successful synthesis and via HPLC along with AES-ICP to evaluate the high drug loading along with a controllable release from the nano-gels. A well-defined nano-shell with size in the 129.3 ± 3.8 nm size range could enhance higher the efficacy of the conjugated-CDDP to Hep-F127 than that of single doses. Moreover, the considerable amount of dual-drug released from thermosensitive nanogels between different conditions (pH = 7.4 and pH = 5.5) in comparison to CDDP from Hep-F127 partially indicated the significantly anti-proliferative ability of Hep-F127/CDDP/Cur to the MCF-7 cell line. Remarkably, drug testing in a xenograft model elucidates the intricate synergism of co-delivery in suppressing tumor growth, which remedies some of the problems affecting in cancer chemotherapy.


Assuntos
Cisplatino/química , Curcumina/química , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Difusão Dinâmica da Luz , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Korean J Parasitol ; 56(5): 453-461, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30419731

RESUMO

The aim of this study is to delineate 'admixed hybrid' and 'introgressive' Fasciola genotypes present in the Fasciola population in Vietnam. Adult liver flukes collected from ruminants in 18 Provinces were morphologically sorted out by naked eyes for small (S), medium (M) and large (L) body shapes; and human samples (n=14) from patients. Nuclear ribosomal (rDNA) ITS1 and ITS2, and mitochondrial (mtDNA) nad1 markers were used for determination of their genetic status. Total 4,725 worm samples of ruminants were tentatively classified by their size: 6% (n=284) small (S)-, 13% (n=614) medium (M)-, and 81% (n=3,827) large (L)-forms. All the representative (n=120, as 40 each group) and 14 human specimens, possessed maternal mtDNA of only F. gigantica and none of F. hepatica. Paternally, all (100%) of the L-(n=40) and 77.5% (n=31) of the M-flukes had single F. gigantica rDNA indicating 'pure' F. gigantica. A majority (90%, n=36) of the S- and 15% (n=6) of the M-worms had single F. hepatica rDNA, indicating their introgressive; the rest (10%, n=4) of the S- and 7.5% (n=3) of the M-flukes had mixture of both F. gigantica and F. hepatica rDNAs, confirming their admixed hybrid genetic status. Fourteen human samples revealed 9 (64%) of pure F. gigantica, 3 (22%) of introgressive and 2 (14%) of admixed hybrid Fasciola spp. By the present study, it was confirmed that the small worms, which are morphologically identical with F. hepatica, are admixed and/or introgressive hybrids of Fasciola spp., and able to be the pathogens of human fascioliasis.


Assuntos
Fasciola hepatica/isolamento & purificação , Fasciolíase/epidemiologia , Fasciolíase/parasitologia , Ruminantes/parasitologia , Animais , DNA de Helmintos , DNA Mitocondrial , DNA Ribossômico , Fasciola hepatica/anatomia & histologia , Fasciola hepatica/classificação , Fasciola hepatica/genética , Genótipo , Humanos , Vietnã/epidemiologia
20.
BMC Infect Dis ; 17(1): 311, 2017 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-28446137

RESUMO

BACKGROUND: Cryptococcosis is an opportunistic infection caused by the encapsulated yeast Cryptococcus neoformans and most remarkably manifests in HIV-infected individuals, especially in the settings of very low CD4 count. Development of cryptococcosis in HIV-uninfected individuals is exceedingly rare and usually signifies a marked immunodeficiency. Cryptococcosis in association with myasthenia gravis or thymoma has been previously documented in only very few cases in the literature. CASE PRESENTATION: We reported a complicated case of severe cutaneous cryptococcosis in a 39-year-old Vietnamese male patient with myasthenia gravis on long-term immunosuppressive therapy. The patient presented with a five month history of recurrent and progressive skin lesions that later on progressed into cryptococcal meningitis. CONCLUSION: Through this case, we aimed to emphasize the importance of including cutaneous cryptococcosis in the differential diagnosis of cutaneous lesions in patients on chronic immunosuppressive therapy. The cutaneous manifestations of cryptococcosis can be the first clue for a disseminated disease, which makes early recognition crucial and life-saving.


Assuntos
Criptococose/complicações , Dermatomicoses/complicações , Meningite Criptocócica/diagnóstico , Miastenia Gravis/complicações , Adulto , Criptococose/patologia , Cryptococcus neoformans/isolamento & purificação , Cryptococcus neoformans/patogenicidade , Dermatomicoses/patologia , Diagnóstico Diferencial , Humanos , Imunossupressores/uso terapêutico , Masculino , Meningite Criptocócica/etiologia , Miastenia Gravis/tratamento farmacológico , Infecções Oportunistas/complicações
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