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2.
Molecules ; 29(11)2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38893494

RESUMO

Syzgium cumini (L.) Skeels powder (S. cumini powder), also known as Jamun, is well-known for its various medical and health benefits. It is especially recognized for its antidiabetic and antioxidant properties. Thus, S. cumini powder is used in various industries, such as the food and cosmetic industries. In this work, the fruit of S. cumini was utilized; its seeds were extracted, dried, and ground into powder. The ground powders were subjected to various techniques such as physicochemical tests, Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometry (XRD), particle size analysis, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and antioxidant analysis. From the physicochemical tests, it was revealed that the jamun seed filler contained cellulose (43.28%), hemicellulose (19.88%), lignin (23.28%), pectin (12.58%), and wax (0.98%). The FTIR analysis supported these results. For instance, a peak at 2889 cm-1 was observed and associated with CH stretching, typically found in methyl and methylene groups, characteristic of cellulose and hemicellulose structures. The XRD results demonstrated that the crystallinity index of the jamun seed filler was 42.63%. The particle analysis indicated that the mean (average) particle size was 25.34 µm. This observation was ensured with SEM results. The EDX spectrum results showed the elemental composition of the fillers. Regarding thermal degradation, the jamun seed filler had the ability to withstand temperatures of up to 316.5 °C. Furthermore, endothermic and exothermic peaks were observed at 305 °C and 400 °C, respectively. Furthermore, the antioxidant property of the powder displayed a peak scavenging activity of 91.4%. This comprehensive study not only underscores the viability of S. cumini powder as a sustainable and effective particulate filler in polymer composites but also demonstrates its potential to enhance the mechanical properties of composites, thereby offering significant implications for the development of eco-friendly materials in various industrial applications.

3.
ACS Omega ; 9(18): 20467-20476, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38737022

RESUMO

Molecular and dissociative hydrogen adsorption of transition metal (TM)-doped [Mo3S13]2- atomic clusters were investigated using density functional theory calculations. The introduced TM dopants form stable bonds with S atoms, preserving the geometric structure. The S-TM-S bridging bond emerges as the most stable configuration. The preferred adsorption sites were found to be influenced by various factors, such as the relative electronegativity, coordination number, and charge of the TM atom. Notably, the presence of these TM atoms remarkably improved the hydrogen adsorption activity. The dissociation of a single hydrogen molecule on TM[Mo3S13]2- clusters (TM = Sc, Cr, Mn, Fe, Co, and Ni) is thermodynamically and kinetically favorable compared to their bare counterparts. The extent of favorability monotonically depends on the TM impurity, with a maximum activation barrier energy ranging from 0.62 to 1.58 eV, lower than that of the bare cluster (1.69 eV). Findings provide insights for experimental research on hydrogen adsorption using TM-doped molybdenum sulfide nanoclusters, with potential applications in the field of hydrogen energy.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38819661

RESUMO

The unmet need for mental health care is a global concern. There is a lack of cross-cultural studies examining adolescent help-seeking behavior from both formal and informal sources, including both high-and lower-income countries. This study investigates mental health help-seeking behavior in eight Asian and European countries. Data from 13,184 adolescents aged 13-15 (51% girls) was analysed using mixed-effects logistic regression with school-wise random intercepts to compare countries and genders. Although a significant proportion of adolescents considered getting or sought informal help, formal help-seeking remained exceptionally low, especially in middle-income countries (< 1%), while it ranged from 2 to 7% in high-income countries. Among adolescents with high emotional and behavioral problems (scoring above the 90th percentile on the Strengths and Difficulties Questionnaire), 1-2% of those in middle-income countries and 6-25% of those in high-income countries sought formal help. Girls generally seek more help than boys. The study shows the most adolescents do not receive formal help for mental health problems. The unmet need gap is enormous, especially in lower-income countries. Informal sources of support, including relatives, peers, and teachers, play a crucial role, especially in lower-income countries.

5.
Chem Biodivers ; 21(7): e202400053, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38646830

RESUMO

Three new oleanane-type triterpene saponins, named camphanosides A-C (1-3), along with five known compounds, chikusetsusaponin IVa (4), spinasaponin A 28-O-glucoside (5), (-)-epicatechin (6), (-)-epicatechin 3-O-gallate (7), and (-)-epigallocatechin 3-O-gallate (8) were isolated from the leaves Camellia phanii Hakoda & Ninh. Their structures were established by 1D and 2D-NMR and mass spectral analysis and chemical methods. Moreover, compounds 1-5 were also evaluated for α-glucosidase inhibitory activity. Compounds 1-3 exhibited moderate α-glucosidase inhibitory activity with IC50 values of 230.7±18.0, 251.4±22.7, and 421.4±25.6 µM, respectively.


Assuntos
Camellia , Inibidores de Glicosídeo Hidrolases , Glicosídeos , Ácido Oleanólico , alfa-Glucosidases , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Camellia/química , alfa-Glucosidases/metabolismo , Ácido Oleanólico/química , Ácido Oleanólico/farmacologia , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/isolamento & purificação , Glicosídeos/química , Glicosídeos/farmacologia , Glicosídeos/isolamento & purificação , Folhas de Planta/química , Relação Estrutura-Atividade , Conformação Molecular , Triterpenos/química , Triterpenos/farmacologia , Triterpenos/isolamento & purificação , Estrutura Molecular
6.
Emerg Infect Dis ; 30(5): 991-994, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38666642

RESUMO

African swine fever virus (ASFV) genotype II is endemic to Vietnam. We detected recombinant ASFV genotypes I and II (rASFV I/II) strains in domestic pigs from 6 northern provinces in Vietnam. The introduction of rASFV I/II strains could complicate ongoing ASFV control measures in the region.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Genótipo , Filogenia , Animais , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/classificação , Vietnã/epidemiologia , Febre Suína Africana/epidemiologia , Febre Suína Africana/virologia , Suínos , Sus scrofa/virologia , Recombinação Genética
7.
One Health ; 18: 100699, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38496339

RESUMO

Antimicrobials are a core aspect of most livestock production systems, especially in low-and middle-income countries. They underpin the efficient use of scarce feed resources and stabilize returns on capital and labor inputs. Antimicrobial use (AMU) contributes to the production of healthy animals, yet AMU in livestock is linked to antimicrobial resistance (AMR) in animals, humans and the environment. The Vietnamese Platform for Antimicrobial Reduction in Chicken Production was implemented during 2016-2019 and was one of Southeast Asia's first interventions focused on AMU reductions in livestock production. The project targeted small-scale commercial poultry farms in the Mekong Delta region of Vietnam using a "randomized before-and-after controlled" study design. It provided farmers with a locally adapted support service (farmer training plan, advisory visits, biosecurity, and antimicrobial replacement products) to help them reduce their reliance on antimicrobials. A partial budget analysis was performed comparing the control group (status-quo) and intervention group (alternative). The median net farm-level benefit of the intervention strategies with the project's support was VND 6.78 million (interquartile range (IR) VND -71.9-89 million) per farm. Without project support the benefit was reduced to VND 5.1 million (IR VND -69.1-87.2 million) to VND 5.3 million (IR -VND 68.9-87.5 million) depending on the antimicrobial alternative product used. At the project level with a focus on AMU and its reduction, subsequently influence on the resistance reduction, our results showed that achieving resistance reduction benefits with the current knowledge and technologies required investment of at least VND 9.1 million (US$ 395.10) per farm during the project's lifetime. The results highlight the positive net profit for the majority of enrolled farms and a reasonable investments from the project. The recommendation focuses on the implementation of policies on financial support, legislation, and information as potential solutions to facilitate the application of intervention strategies to reduce AMU in poultry production.

8.
Haemophilia ; 30(3): 609-616, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38523289

RESUMO

BACKGROUND: The healthcare systems in Asia vary greatly due to the socio-economic and cultural diversities which impact haemophilia management. METHODS: An advisory board meeting was conducted with experts in haemophilia care from Asia to understand the heterogeneity in clinical practices and care provision in the region. FINDINGS: The overall prevalence of haemophilia in Asia ranges between 3 and 8.58/100,000 patients. Haemophilia A was more prevalent as compared to haemophilia B with a ratio of around 5:1. There is under-diagnosis in the region due to lack of diagnosis, registries and/or lack of appropriate facilities in suburban areas. Most patients are referred to the haematologists by their families or primary care physicians, while some are identified during bleeding episodes. Genetic testing faces obstacles like resource constraints, services available at limited centres and unwillingness of patients to participate. Prophylaxis is offered for people with haemophilia (PWH) with a severe bleeding phenotype. Recombinant factors are approved in most countries across the region and are the preferred therapy. The challenges highlighted for not receiving a high standard of care include patients' reluctance to use an intravenous treatment, poor patient compliance due to frequency of infusions, budget constraints and lack of funding, insurance, availability and accessibility of factor concentrates. Prevalence of neutralizing antibodies ranged from 5% to 20% in the region. Use of immune tolerance induction and bypassing agents to treat inhibitors depends on their cost and availability. CONCLUSION: Haemophilia care in Asia has evolved to a great extent. However, some challenges remain for which a strategic approach along with multi-stakeholder involvement are needed.


Assuntos
Hemofilia A , Humanos , Hemofilia A/terapia , Hemofilia A/epidemiologia , Ásia/epidemiologia , Prevalência , Atenção à Saúde , Hemofilia B/terapia , Hemofilia B/epidemiologia
9.
J Neurochem ; 168(5): 899-909, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38299375

RESUMO

Cofilactin rods (CARs), which are 1:1 aggregates of cofilin-1 and actin, lead to neurite loss in ischemic stroke and other disorders. The biochemical pathways driving CAR formation are well-established, but how these pathways are engaged under ischemic conditions is less clear. Brain ischemia produces both ATP depletion and glutamate excitotoxicity, both of which have been shown to drive CAR formation in other settings. Here, we show that CARs are formed in cultured neurons exposed to ischemia-like conditions: oxygen-glucose deprivation (OGD), glutamate, or oxidative stress. Of these conditions, only OGD produced significant ATP depletion, showing that ATP depletion is not required for CAR formation. Moreover, the OGD-induced CAR formation was blocked by the glutamate receptor antagonists MK-801 and kynurenic acid; the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitors GSK2795039 and apocynin; as well as an ROS scavenger. The findings identify a biochemical pathway leading from OGD to CAR formation in which the glutamate release induced by energy failure leads to activation of neuronal glutamate receptors, which in turn activates NADPH oxidase to generate oxidative stress and CARs.


Assuntos
Metabolismo Energético , Ácido Glutâmico , Neurônios , Animais , Células Cultivadas , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/fisiologia , Ácido Glutâmico/metabolismo , Ratos , Trifosfato de Adenosina/metabolismo , Glucose/metabolismo , Glucose/deficiência , Actinas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , NADPH Oxidases/metabolismo , Acetofenonas/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Maleato de Dizocilpina/farmacologia , Ácido Cinurênico/farmacologia , Ácido Cinurênico/metabolismo , Ratos Sprague-Dawley
10.
PLoS One ; 19(1): e0296448, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38180980

RESUMO

BACKGROUND: The WHO has issued a call to action urging countries to accelerate the rollout of new WHO-recommended shorter all-oral treatment regimens for drug-resistant TB (DR-TB), which remains a public-health crisis. The all-oral, 6-month BPaL/M regimen comprises 3-4 drugs: pretomanid used in combination with bedaquiline and linezolid, with or without moxifloxacin. This regimen has been recommended by the WHO for use in DR-TB patients instead of ≥9-month (up to 24-month) regimens. This study aims to project this regimen's use, along with its components bedaquiline, pretomanid and linezolid, and other treatments for DR-TB globally through 2026. It is intended to guide global health stakeholders in planning and budgeting for DR-TB interventions. Projected usage could help estimate cost of the individual components of DR-TB regimens over time. METHODS: Semi-structured interviews were conducted with national TB programme participants in key countries to gather intelligence on established plans and targets for use of various DR-TB treatment regimens from 2023 to 2026. These data informed development of projections for the global use of regimens and drugs. RESULTS: Consistent global growth in the use of shorter regimens in DR-TB treatment was shown: BPaLM reaching 126,792 patients, BPaL reaching 43,716 patients, and the 9-11-month all-oral bedaquiline-based regimen reaching 13,119 patients by 2026. By 2026, the longer all-oral regimen is projected to be used by 19,262 patients, and individualised treatment regimens by 15,344 patients. CONCLUSION: The study shows BPaL/M will be used in majority of DR-TB patients by 2024, reaching 78% by 2026. However, national efforts to scale-up, case-finding, monitoring, drug-susceptibility testing, and implementation of new treatments will be essential for ensuring they are accessible to all eligible patients in the coming years and goals for ending TB are met. There is an urgent need to engage communities in capacity building and demand generation.


Assuntos
Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Linezolida , Protocolos Clínicos , Transporte Biológico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
11.
Chem Biodivers ; 21(3): e202302105, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38269614

RESUMO

Four previously undescribed compounds named phyllancosides A and B (1 and 2), and phyllancochines A and B (3 and 4) together with ten known compounds (5-14) were isolated from the aerial parts of Phyllanthus cochinchinensis Spreng. Their chemical structures were elucidated on the basis of comprehensive analysis of IR, HR-ESI-MS, 1D and 2D NMR spectra. The absolute configurations of 1 and 2 were determined by electronic circular dichroism (ECD) spectra. Compounds 3, 4, and 10 showed antimicrobial activity against E. faecalis, S. aureus, and B. cereus with the MIC values in range of 32-256 µg/mL. Compound 11 inhibited E. faecalis and B. cereus, and 7 inhibited S. aureus with the MIC values in range of 64-128 µg/mL. In addition, compounds 1, 3, 4, 8, and 9 showed significantly NO production inhibitory activity in LPS activated RAW 264.7 cells with IC50 values ranging from 36.57 to 56.34 µM.


Assuntos
Anti-Infecciosos , Lipopolissacarídeos , Animais , Camundongos , Células RAW 264.7 , Estrutura Molecular , Lipopolissacarídeos/farmacologia , Staphylococcus aureus , Óxido Nítrico , Componentes Aéreos da Planta/química , Anti-Infecciosos/análise
12.
RSC Adv ; 13(42): 29141-29151, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37800131

RESUMO

In this study, the aerial parts of mature Vietnamese Euphorbia tithymaloides plants were put through cytotoxic, anti-diabetic, and phytocompositional evaluations. Specifically, four extracts (petroleum ether (PE), ethyl acetate (EA), methanol (Me), and aqueous (W)) were prepared by maceration at room temperature. All extracts, together with some isolated compounds, were investigated for cytotoxicity against some human normal and cancer cell lines (fibroblasts, HeLa, NCI-H460, HepG2, MCF-7, and Jurkat) using the standardized modified sulforhodamine B (SRB) assay. Additionally, the anti-diabetic activity of extracts and compounds was evaluated via their α-glucosidase inhibitory capacity. The obtained results indicated that Vietnamese E. tithymaloides extracts exhibited moderate cytotoxic activity, among which the PE extract possessed the highest values, on the NCI-H460 cell line. Second, the aqueous extract was revealed to possess very high α-glucosidase inhibitory activity (IC50 = 113.75 ± 14.02 µg ml-1). From the PE extract, three new jatrophane diterpenoids (named tithymal A, tithymal B, and tithymal C) and two known ones were isolated and structurally elucidated using NMR and MS spectroscopies. Noticeably, tithymal A exhibited significantly high inhibitory activity against α-glucosidase (IC50 = 10.71 ± 0.52 µg ml-1). These observations have significantly highlighted the medicinal potential of Vietnamese E. tithymaloides and expanded its scientific fascination.

13.
ACS Omega ; 8(37): 33412-33425, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37744831

RESUMO

Valorization of pineapple peel waste is an attractive research topic because of the huge quantities of this byproduct generated from pineapple processing industries. In this study, the extract from pineapple waste was collected to produce a hydrogel-like form containing bacterial cellulose fibers with a three-dimensional structure and nanoscale diameter by the Acetobacter xylinum fermentation process. The bacterial cellulose suspension was subsequently activated by freeze-drying, affording lightweight aerogels as potential adsorbents in wastewater treatment, in particular the adsorptive removal of organic dyes. Intensive tests were carried out with the adsorption of methylene blue, a typical cationic dye, to investigate the influence of adsorption conditions (temperature, pH, initial dye concentration, time, and experiment scale) and aerogel-preparation parameters (grinding time and bacterial cellulose concentration). The bacterial cellulose-based aerogels exhibited high adsorption capacity not only for methylene blue but also for other cationic dyes, including malachite green, rhodamine B, and crystal violet (28-49 mg/g). However, its activity was limited for most of the anionic dyes, such as methyl orange, sunset yellow, and quinoline yellow, due to the repulsion of these anionic dyes with the aerogel surface, except for the case of congo red. It is also an anionic dye but has two amine groups providing a strong interaction with the hydroxyl group of the aerogel via hydrogen bonding. Indeed, the aerogel has a substantially large congo red-trapping capacity of 101 mg/g. Notably, the adsorption process exhibited similar performances, upscaling the solution volume to 50 times. The utilization of abundant agricultural waste in the simple aerogel preparation to produce a highly efficient and biodegradable adsorbent is the highlight of this work.

14.
Belitung Nurs J ; 9(4): 331-338, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37645583

RESUMO

Background: Intestinal stomas are surgical interventions that have an impact on both physical and psychological health, necessitating patient self-care. Insufficient knowledge regarding peristomal skin care, prevention, and treatment of potential problems can lead to an increase in stoma-related complications. Objective: This study aimed to assess patients' knowledge of self-care for intestinal stomas and examine the relationship between background information and self-care knowledge. Methods: A descriptive cross-sectional study was conducted from December 2021 to December 2022 at the Can Tho University of Medicine and Pharmacy Hospital in Vietnam, involving 74 participants with intestinal stomas. A questionnaire consisting of 24 closed-ended questions was used to evaluate participants' knowledge of self-care for intestinal stomas. Descriptive statistics, Chi-square, and Fisher's exact tests were employed for data analysis. Results: The findings revealed that 54.1% of participants had good knowledge of general self-care for intestinal stomas. The distribution of good knowledge among participants was as follows: basic knowledge (66.2%), self-care practice (56.8%), recognizing and managing complications (31.1%), and dietary knowledge (64.8%). Significant relationships were observed between participants' self-care knowledge and their education level (p = 0.002), marital status (p = 0.017), nurses' education (p = 0.021), and hospitalization (p = 0.001). Conclusion: The proportion of participants with good knowledge of self-care for intestinal stomas was relatively low, and it was associated with individuals' education level, marital status, nurses' education, and hospitalization. This study highlights the need for ongoing development of educational programs on self-care for intestinal stomas. These programs should be tailored to address the specific needs of each patient and aim to improve their self-care knowledge in a meaningful and sustainable manner. By investing in patient education, healthcare professionals, particularly nurses, can assist individuals with intestinal stomas in achieving better outcomes and preventing potential complications.

15.
Proc Natl Acad Sci U S A ; 120(34): e2309043120, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37590416

RESUMO

Toxoplasma gondii is responsible for toxoplasmosis, a disease that can be serious when contracted during pregnancy, but can also be a threat for immunocompromised individuals. Acute infection is associated with the tachyzoite form that spreads rapidly within the host. However, under stress conditions, some parasites can differentiate into cyst-forming bradyzoites, residing mainly in the central nervous system, retina and muscle. Because this latent form of the parasite is resistant to all currently available treatments, and is central to persistence and transmission of the parasite, specific therapeutic strategies targeting this developmental stage need to be found. T. gondii contains a plastid of endosymbiotic origin called the apicoplast, which is an appealing drug target because it is essential for tachyzoite viability and contains several key metabolic pathways that are largely absent from the mammalian host. Its function in bradyzoites, however, is unknown. Our objective was thus to study the contribution of the apicoplast to the viability and persistence of bradyzoites during chronic toxoplasmosis. We have used complementary strategies based on stage-specific promoters to generate conditional bradyzoite mutants of essential apicoplast genes. Our results show that specifically targeting the apicoplast in both in vitro or in vivo-differentiated bradyzoites leads to a loss of long-term bradyzoite viability, highlighting the importance of this organelle for this developmental stage. This validates the apicoplast as a potential area to look for therapeutic targets in bradyzoites, with the aim to interfere with this currently incurable parasite stage.


Assuntos
Apicoplastos , Cistos , Toxoplasma , Toxoplasmose , Animais , Feminino , Gravidez , Humanos , Toxoplasma/genética , Sistema Nervoso Central , Mamíferos
16.
Chem Biodivers ; 20(9): e202300904, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37550247

RESUMO

A chemical investigation of K. heteroclite led to isolation of two new dibenzocyclooctadienes (1 and 2) together with 14 known compounds (3-16) by using multiple chromatographic techniques. New compounds (1 and 2) were obtained and identified by spectroscopic methods (HR-ESI-MS, 1D and 2D NMR, and ECD) as well as by comparison of their experimental data with those reported in the literatures. All the isolates were evaluated for their ability to modulate TNF-α production in lipopolysaccharide (LPS) stimulated RAW264.7 cells. Among them, compound 5 displayed the most inhibition against tumor necrosis factor (TNF)-α production with IC50 value of 6.16±0.14 µM. Whereas, compounds (1, 3, and 6) showed the significant inhibition (IC50 values ranging from 9.41 to 14.54 µM), and compounds (2, 4, 9, 10, 13, 15, and 16) exhibited moderate inhibition (IC50 values ranging from 19.27 to 40.64 µM) toward TNF-α production, respectively.


Assuntos
Kadsura , Lignanas , Kadsura/química , Fator de Necrose Tumoral alfa , Lignanas/farmacologia , Lignanas/química , Anti-Inflamatórios/farmacologia , Fenóis , Estrutura Molecular
17.
Nanomaterials (Basel) ; 13(14)2023 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-37513150

RESUMO

Developing highly efficient and durable hydrogen evolution reaction (HER) electrocatalysts is crucial for addressing the energy and environmental challenges. Among the 2D-layered chalcogenides, MoSe2 possesses superior features for HER catalysis. The van der Waals attractions and high surface energy, however, stack the MoSe2 layers, resulting in a loss of edge active catalytic sites. In addition, MoSe2 suffers from low intrinsic conductivity and weak electrical contact with active sites. To overcome the issues, this work presents a novel approach, wherein the in situ incorporated diethylene glycol solvent into the interlayers of MoSe2 during synthesis when treated thermally in an inert atmosphere at 600 °C transformed into graphene (Gr). This widened the interlayer spacing of MoSe2, thereby exposing more HER active edge sites with high conductivity offered by the incorporated Gr. The resulting MoSe2-Gr composite exhibited a significantly enhanced HER catalytic activity compared to the pristine MoSe2 in an acidic medium and demonstrated a superior HER catalytic activity compared to the state-of-the-art Pt/C catalyst, particularly at a high current density beyond ca. 55 mA cm-2. Additionally, the MoSe2-Gr catalyst demonstrated long-term electrochemical stability during HER. This work, thus, presents a facile and novel approach for obtaining an efficient MoSe2 electrocatalyst applicable in green hydrogen production.

18.
Malar J ; 22(1): 204, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37408026

RESUMO

BACKGROUND: Despite recent reductions in Vietnam, malaria transmission persists in some areas in forests and farmlands where a high density of Anopheles mosquitoes relative to other environments occurs. To inform effective malaria control measures, it is important to understand vector bionomics and the malaria transmission role of Anopheles spp. in the highland regions of Vietnam. This study was conducted to quantify the abundance, composition and biting behaviour of the Anopheles mosquito population, and the proportion of Plasmodium spp. infected mosquitoes collected from forest and agricultural farm sites in Gia Lai province, Vietnam. METHODS: Forest and agricultural farm sites in Gia Lai province were selected for mosquito collections (total eight sites). Mosquito collection was performed by Human-baited Double Net Trap (HDNT), animal-baited traps (ABT) using cattle, and CDC light traps. Captured mosquitoes were identified morphologically, and salivary glands of Anopheles mosquitoes were examined for sporozoites using microscopy. Plasmodium infection was determined by Polymerase Chain Reaction (PCR), and identification of blood meal type was determined by PCR and diffuse serum agglutination assay. RESULTS: A total of 1815 Anopheles mosquitoes belonging to 19 species were collected by ABT (n = 1169), HDNT (n = 471) and CDC light trap (n = 175). Anopheles abundance and diversity varied by district and environment. Capture by HDNT of Anopheles of vectorial concern was observed between early evening and early morning. Plasmodium vivax infection was determined by PCR in two Anopheles dirus specimens captured by HDNT in forest sites. Blood from a range of hosts could, including human blood, could be detected in species considered primary and secondary vectors An. dirus, and Anopheles aconitus, and Anopheles maculatus, respectively. CONCLUSIONS: A low number of Anopheles spp. considered primary vectors of concern and very low numbers of Plasmodium spp. infected Anopheles mosquitoes were captured at the end of the rainy season in the Central Highlands of Vietnam. However, capture species of vectorial concern by HDNT throughout the early to late evening demonstrates that use of additional personal protective measures could supplement current preventative measures, such as bed nets to prevent exposure to vectors of concern in this region.


Assuntos
Anopheles , Malária , Plasmodium , Humanos , Animais , Bovinos , Fazendas , Vietnã/epidemiologia , Mosquitos Vetores , Malária/epidemiologia , Florestas
19.
Chem Biodivers ; 20(8): e202300853, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37409765

RESUMO

A chemical study of the methanol extract of the aerial parts of Achyranthes aspera led to the isolation of four new flavonoid C-glycosides (1-4) along with eight known analogs (5-12). Their structures were elucidated by a combination of spectroscopic data analysis, HR-ESI-MS, 1D and 2D NMR spectra. All the isolates were evaluated their NO production inhibitory activity in LPS-activated RAW264.7 cells. Compounds 2, 4, and 8-11 showed significant inhibition with IC50 values ranging from 25.06 to 45.25 µM, compared to that of the positive control compound, L-NMMA, IC50 value of 32.24 µM, whereas the remaining compounds were weak inhibitory activity with IC50 values over 100 µM. This is the first report of 7 from Amaranthaceae family, and 11 from the genus Achyranthes.


Assuntos
Achyranthes , Flavonoides , Flavonoides/farmacologia , Flavonoides/química , Achyranthes/química , Óxido Nítrico , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Glicosídeos/farmacologia , Glicosídeos/química , Estrutura Molecular
20.
Plants (Basel) ; 12(12)2023 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-37375984

RESUMO

Salinity is a severe stress that causes serious losses in rice production worldwide. This study, for the first time, investigated the effects of fulvic acid (FA) with various concentrations of 0.125, 0.25, 0.5, and 1.0 mL/L on the ability of three rice varieties, Koshihikari, Nipponbare, and Akitakomachi, to cope with a 10 dS/m salinity level. The results show that the T3 treatment (0.25 mL/L FA) is the most effective in stimulating the salinity tolerance of all three varieties by enhancing their growth performance. T3 also promotes phenolic accumulation in all three varieties. In particular, salicylic acid, a well-known salt-stress-resistant substance, is found to increase during salinity stress in Nipponbare and Akitakomachi treated with T3 by 88% and 60%, respectively, compared to crops receiving salinity treatment alone. Noticeably, the levels of momilactones A (MA) and B (MB) fall in salt-affected rice. However, their levels markedly rise in rice treated with T3 (by 50.49% and 32.20%, respectively, in Nipponbare, and by 67.76% and 47.27%, respectively, in Akitakomachi), compared to crops receiving salinity treatment alone. This implies that momilactone levels are proportional to rice tolerance against salinity. Our findings suggest that FA (0.25 mL/L) can effectively improve the salinity tolerance of rice seedlings even in the presence of a strong salt stress of 10 dS/m. Further studies on FA application in salt-affected rice fields should be conducted to confirm its practical implications.

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