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1.
Med J Armed Forces India ; 80(3): 362-364, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38799991

RESUMO

A pelvic digit is a rare congenital anomaly and is often discovered incidentally. We present a 44-year-old male patient with bilateral pelvic digits discovered on a pelvic radiograph during a primary survey after a road traffic accident. Supplementary imaging using computed tomographic imaging confirmed the bilateral finding which is rare. No surgical attempt was made at removal as the patient remained asymptomatic.

2.
J Orthop Case Rep ; 14(3): 141-145, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38560322

RESUMO

Introduction: Distal junctional failure (DJF) is underreported when compared to proximal junctional failure. DJF arising due to spondylodiscitis has never been reported in the literature. Case Report: A 45-year-old lady with a body mass index of 33 presented with a long-standing inability to walk due to myelopathy secondary to continuous ossified posterior longitudinal ligament and ossified ligamentum flavum. Posterior fusion and laminectomy were done from D2 to L2. She had an initial wound breakdown with a surgical site infection, but after 6 weeks, she developed spondylodiscitis at the distal instrumented vertebra, leading to DJF. She was started on appropriate antibiotics and an extension of fusion. Conclusion: This report demonstrates and discusses the management of a rare case of DJF arising due to spondylodiscitis of the last instrumented vertebra.

3.
Med J Armed Forces India ; 80(2): 227-233, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525453

RESUMO

Osteogenesis imperfecta (OI) is commonly associated with fragility fractures. It is due to abnormality in the quantity and quality of collagen type 1 caused by mutations in COL1A1 and COL1A2 genes. Patients with OI would also have blue sclera, ligament hyperlaxity, dentinogenesis imperfecta, hearing abnormality, and short stature. Surgical management is preferred to conservative treatment in long bone fractures. For malunited fractures, Sofield-Millar or multiple osteotomies at different sites of deformities are performed with additional intramedullary device to stabilize the bone. This is a case of femur fracture with multilevel CORAs in an adolescent patient with post-trauma OI in which z-osteotomies were performed and stabilized with titanium elastic nails resulting in good outcomes clinically and radiologically.

4.
Front Chem ; 11: 1118454, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36959877

RESUMO

Medicinal plants are long known for their therapeutic applications. Tinospora cordifolia (commonly called gulancha or heart-leaved moonseed plant), a herbaceous creeper widely has been found to have antimicrobial, anti-inflammatory, anti-diabetic, and anti-cancer properties. However, there remains a dearth of reports regarding its antibiofilm activities. In the present study, the anti-biofilm activities of phytoextractof T. cordifolia and the silver nanoparticles made from this phytoextract were tested against the biofilm of S.taphylococcus aureus, one of the major nosocomial infection-producing bacteria taking tetracycline antibiotic as control. Both phytoextract from the leaves of T. cordifolia, and the biogenic AgNPs from the leaf extract of T. cordifolia, were found successful in reducing the biofilm of Staphylococcus aureus. The biogenic AgNPs formed were characterized by UV- Vis spectroscopy, Field emission Scanning Electron Microscopy (FE- SEM), and Dynamic light scattering (DLS) technique. FE- SEM images showed that the AgNPs were of size ranging between 30 and 50 nm and were stable in nature, as depicted by the zeta potential analyzer. MIC values for phytoextract and AgNPs were found to be 180 mg/mL and 150 µg/mL against S. aureusrespectively. The antibiofilm properties of the AgNPs and phytoextract were analyzed using the CV assay and MTT assay for determining the reduction of biofilms. Reduction in viability count and revival of the S. aureus ATCC 23235 biofilm cells were analyzed followed by the enfeeblement of the EPS matrix to quantify the reduction in the contents of carbohydrates, proteins and eDNA. The SEM analyses clearly indicated that although the phytoextracts could destroy the biofilm network of S. aureuscells yet the biogenicallysynthesizedAgNPs were more effective in biofilm disruption. Fourier Transformed Infrared Radiations (FT- IR) analyses revealed that the AgNPs could bring about more exopolysaccharide (EPS) destruction in comparison to the phytoextract. The antibiofilm activities of AgNPs made from the phytoextract were found to be much more effective than the non-conjugated phytoextract, indicating the future prospect of using such particles for combatting biofilm-mediated infections caused by S aureus.

5.
Bioresour Technol ; 373: 128743, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36791974

RESUMO

In this study, the cultivation and harvesting of Arthrospira platensis biomass were proposed via simple, safe, and efficient techniques for direct consumption. Cultivation of microalgae in a covered macrobubble column under outdoor conditions resulted in significant differences (p < 0.05) with a maximum dry cell weight (Xm) of 0.959 ± 0.046 g/L. Notably, outdoor cultures resulted in approximately twofold biomass compared to indoor cultures. This outcome shows that the developed outdoor setup integrated with solar panels while utilising Malaysia's weather and atmospheric air as carbon sources is viable. Meanwhile, for harvesting, the screening showed that the fungus isolated from mould soybean cake (tempeh) starter indicated the highest harvesting efficiency, which was then further identified as Rhizopus microsporus, microscopically and molecularly. Overall, the economical and portable setup of outdoor cultivation coupled with safe harvesting via locally isolated fungus from tempeh as a bioflocculant would provide sustainability to produce A. platensis biomass.


Assuntos
Microalgas , Spirulina , Glycine max , Fotobiorreatores , Biomassa , Fungos
6.
Front Microbiol ; 13: 955683, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35903478

RESUMO

Determination of the quality of food products is an essential key factor needed for safe-guarding the quality of food for the interest of the consumers, along with the nutritional and sensory improvements that are necessary for delivering better quality products. Bacteriocins are a group of ribosomally synthesized antimicrobial peptides that help in maintaining the quality of food. The implementation of multi-omics approach has been important for the overall enhancement of the quality of the food. This review uses various recent technologies like proteomics, transcriptomics, and metabolomics for the overall enhancement of the quality of food products. The matrix associated with the food products requires the use of sophisticated technologies that help in the extraction of a large amount of information necessary for the amelioration of the food products. This review would provide a wholesome view of how various recent technologies can be used for improving the quality food products and for enhancing their shelf-life.

7.
Appl Biochem Biotechnol ; 194(10): 4800-4816, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35655004

RESUMO

Candida albicans is the most prevalent fungus in humans, producing infections ranging from mucosal to systemic. C. albicans colonizes mucosal surfaces asymptomatically as commensal, but, if the host environment is disrupted, or if the host immune system is compromised, C. albicans can multiply and infect almost all places in the host. The present study was aimed to identify a promising antibiofilm agent against Candida albicans biofilm. Through the molecular docking approach, it was identified that Eicosane was the top hit among the alkanes screened. Furthermore, in vitro analysis revealed that Eicosane at 100 µg/mL was able to inhibit 60% of C. albicans biofilm without inhibiting the growth. Moreover, light microscopic investigation unveiled the significant reduction in the adhesion and colonization of yeast cells to the matrix on Eicosane-treated samples. The CLSM images showing a reduction in biomass and thickness of C. albicans biofilm in the presence of Eicosane were validated using COMSTAT. The results were well corroborated with SEM micrograph in which a pellucid gap between the cells was observed and colonization was considerably reduced. Further from qPCR analysis, the genes responsible for biofilm formation and hyphal growth were found to be downregulated in the presence of Eicosane. Similarly, Eicosane at BIC was able to significantly inhibit the adhesion and colonization of yeast cells on the chorion of the zebrafish embryos. Moreover, the binding ability of Eicosane to ALS3 was revealed through docking and molecular dynamics (MD) simulation studies.


Assuntos
Candida albicans , Peixe-Zebra , Alcanos , Animais , Antifúngicos/farmacologia , Biofilmes , Humanos , Simulação de Acoplamento Molecular
8.
J Tradit Complement Med ; 12(4): 361-366, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35747355

RESUMO

Background: Exposure to chronic stress induces oxidative damage which alters the dynamic balance between antioxidant and pro-oxidant activities in the brain. Tualang honey (TH) is a Malaysian wild multifloral honey which has been shown to contain high amount antioxidants. DHA-rich fish oil is a form of omega-3 fatty acids found in fish which also possesses some antioxidant activity. This study aimed to evaluate anti-stress activity of DHA-rich fish oil, TH and their combination on several parameters of oxidative stress in chronic stress rat model. Methods: Fifty male Sprague Dawley rats were divided into (i) control, (ii) stress-exposed, (iii) stress-exposed and treated with TH (1 g/kg body weight twice daily), (iv) stress-exposed and treated with DHA-rich fish oil (450 mg/kg body weight twice daily), and (v) stress-exposed and treated with a combination of TH and DHA-rich fish oil. The chronic stress regimen consisted of a combination of restraint stress and a swim stress test for 28 days. Results: DHA-rich fish oil and TH significantly (p < 0.05) supressed stress-induced elevation of serum corticosterone and lipid peroxidation, and caused a significant increase in total antioxidant capacity. For glutathione status, only TH significantly reduced stress-induced elevation of oxidised glutathione (GSSG) and normalised GSH/GSSG ratio. Conclusion: Both DHA-rich fish oil and TH have protective effects against brain oxidative stress but consuming these substances together does not seem to provide an additional benefit compared to consuming them separately.

9.
PLoS One ; 16(11): e0260281, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34843539

RESUMO

BACKGROUND: There is a growing need to use green alternative larvicidal control for Aedes larvae compared to chemical insecticides. Substantial reliance on chemical insecticides caused insecticide resistance in mosquito populations. Thus, research for alternate chemical compounds from natural products is necessary to control Aedes larvae. This study explores the analysis of chemical compositions from Areca catechu nut as a potential larvicide for Aedes (Diptera: Culicidae). METHODS: The Areca catechu nut collected from Ipoh, Perak, Malaysia was grounded into powder and used for Soxhlet extraction. The chemical analysis of the extracts and their structures were identified using the GCMS-QP2010 Ultra (Shimadzu) system. National Institute of Standards and Technology (NIST) Chemistry WebBook, Standard Reference Database 69 (https://webbook.nist.gov/chemistry/) and PubChem (https://pubchem.ncbi.nlm.nih.gov/), the two databases used to retrieve the synonyms, molecular formula, molecular weight, and 2-dimensional (2D) structure of chemical compounds. Next, following WHO procedures for larval bioassays, the extracts were used to asses larvicidal activity against early 4th instar larvae of Aedes aegypti and Aedes albopictus. RESULTS: The larvicidal activities were observed against early 4th stage larvae with different concentrations in the range from 200 mg/L to 1600 mg/L. The LC50 and LC95 of Aedes aegypti were 621 mg/L and 2264 mg/L respectively; whereas the LC50 and LC95 of Aedes albopictus were 636 mg/L and 2268 mg/L respectively. Mortality was not observed in the non-target organism test. The analysis using gas chromatography and mass spectrometer recovered several chemical compounds such as Arecaidine, Dodecanoic acid, Methyl tetradecanoate, Tetradecanoic acid , and n-Hexadecanoic acid bioactive components. These chemical constituents were used as additive formulations in pesticides, pest control, insect repellent, and insecticidal agents. CONCLUSIONS: Our study showed significant outcomes from the extract of Areca catechu nut and it deserves further investigation in relation to chemical components and larvicidal actions between different species of Aedes mosquitoes. Even though all these findings are fundamental, it may have some interesting potentials to be developed as natural bio-larvicidal products.


Assuntos
Aedes/efeitos dos fármacos , Areca/química , Inseticidas/toxicidade , Nozes/química , Extratos Vegetais/toxicidade , Aedes/fisiologia , Animais , Controle de Insetos , Repelentes de Insetos/química , Repelentes de Insetos/isolamento & purificação , Repelentes de Insetos/toxicidade , Inseticidas/química , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Larva/fisiologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
11.
Skeletal Radiol ; 50(12): 2525-2535, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34021364

RESUMO

OBJECTIVES: CT examination can potentially be utilised for early detection of bone density changes with no additional procedure and radiation dose. We hypothesise that the Hounsfield unit (HU) measured from CT images is correlated to the t-scores derived from dual energy X-ray absorptiometry (DXA) in multiple anatomic regions. MATERIALS & METHODS: Data were obtained retrospectively from all patients who underwent both CT examinations - brain (frontal bone), thorax (T7), abdomen (L3), spine (T7 & L3) or pelvis (left hip) - and DXA between 2014 and 2018 in our centre. To ensure comparability, the period between CT and DXA studies must not exceed one year. Correlations between HU values and t-scores were calculated using Pearson's correlation. Receiver operating characteristic (ROC) curves were generated, and the area under the curve (AUC) was used to determine threshold HU values for predicting osteoporosis. RESULTS: The inclusion criteria were met by 1043 CT examinations (136 head, 537 thorax, 159 lumbar and 151 left hip). The left hip consistently provided the most robust correlations (r = 0.664-0.708, p < 0.001) and the best AUC (0.875-0.893). Meanwhile, thorax T7 and lumbar L3 showed average correlations (range of r values is 0.497-0.679, p < 0.001, AUC range = 0.680-0.783, 95% CI 0.561-0.922, all p < 0.02) and moderate AUC (0.680-0.783). Frontal bone shows low correlation and weak AUC with r < 0.5, AUC = 0.538-0.655, all p > 0.05. CONCLUSION: HU values derived from the hip, T7 and L3 provided a good to moderate correlation to t-scores with a good prediction for osteoporosis. The suggested optimal thresholds may be used in clinical settings after external validations are performed.


Assuntos
Densidade Óssea , Vértebras Lombares , Abdome , Absorciometria de Fóton , Humanos , Vértebras Lombares/diagnóstico por imagem , Pelve/diagnóstico por imagem , Estudos Retrospectivos , Tórax , Tomografia Computadorizada por Raios X
12.
Sci Rep ; 10(1): 19245, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33159109

RESUMO

Four different tests showed the effectiveness of Azolla pinnata plant extracts against Aedes aegypti and Aedes albopictus mosquitoes. In the adulticidal test, there was a significant increase in mortality as test concentration increases and A. pinnata extracts showed LC50 and LC95 values of 2572.45 and 6100.74 ppm, respectively, against Ae. aegypti and LC50 and LC95 values of 2329.34 and 5315.86 ppm, respectively, against Ae. albopictus. The ovicidal test showed 100% eggs mortality for both species tested for all the concentrations tested at 1500 ppm, 1000 ppm, 500 ppm, 250 ppm and 125 ppm. Both tested samples of Ae. aegypti and Ae. albopictus did not lay any eggs in the plastic cups filled with the A. pinnata extract but instead opted to lay eggs in the plastic cups filled with water during the oviposition deterrence test. Similarly, the non-choice test of Ae. aegypti mosquitoes laid eggs on the sucrose solution meant for the nutrient source of the mosquitoes instead of in the plastic cup that was designed to facilitate oviposition filled with the extract. This clearly indicates the presence of bioactive compounds which are responsible in adulticidal and ovicidal activity in Aedes mosquitoes and at the same time inducing repellence towards the mosquitoes. The LC-MS results showed mainly three important chemical compounds from A. pinnata extracts such as 1-(O-alpha-D-glucopyranosyl)-(1,3R,25R)-hexacosanetriol, Pyridate and Nicotinamide N-oxide. All these chemicals have been used for various applications such as both emulsion and non-emulsion type of cosmetics, against mosquito vector such as Culex pipens and Anopheles spp. Finally, the overall view of these chemical components from A. pinnata extracts has shown the potential for developing natural product against dengue vectors.


Assuntos
Aedes/crescimento & desenvolvimento , Anopheles/crescimento & desenvolvimento , Culex/crescimento & desenvolvimento , Gleiquênias/química , Inseticidas , Extratos Vegetais , Animais , Inseticidas/química , Inseticidas/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia
13.
PLoS One ; 15(10): e0241320, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33104734

RESUMO

The rapid growth of industrial and agricultural activities in Malaysia are leading to the impairment of most of the rivers in recent years through realising various trace metals. This leads to toxicity, particularly when the toxic has entered the food chain. Perak River is one of the most dynamic rivers for the Malaysian population. Therefore, in consideration of the safety issue, this study was conducted to assess the concentration of such metals (Cd, Cu, Zn, Fe, and Pb) in the muscles of most widely consumed fish species (Barbonymus schwanenfeldii, Puntius bulum, Puntius daruphani, Hexanematichthys sagor, Channa striatus, Mystacoleucus marginatus, and Devario regina) from different locations of Perak River, Malaysia by employing inductively coupled plasma optical emission spectroscopy (ICP-OES). Among the trace metals, Fe and Cd were found to be the highest (29.33-148.01 µg/g) and lowest (0.16-0.49 µg/g) concentration in all of the studied species, respectively. Although the estimated daily intakes (µg/kg/day) of Cd (0.65-0.85), Fe (79.27-352.00) and Pb (0.95-12.17) were higher than their reference, the total target hazard quotients values suggested that the local residents would not experience any adverse health effects from its consumption. In contrast, the target cancer risk value suggested that all fish species posed a potential cancer risk due to Cd and cumulative cancer risk values, strongly implying that continuous consumption of studied fish species would cause cancer development to its consumers.


Assuntos
Rios , Alimentos Marinhos/efeitos adversos , Oligoelementos/análise , Poluentes Químicos da Água/análise , Animais , Bioacumulação , Cyprinidae , Ecossistema , Comportamento Alimentar , Água Doce , Geografia , Sedimentos Geológicos/química , Malásia , Neoplasias/epidemiologia , Neoplasias/etiologia , Medição de Risco , Fatores de Risco , Especificidade da Espécie
14.
ScientificWorldJournal ; 2019: 8605743, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31780876

RESUMO

Analysis of fatty acid contents and pharmacological properties of Pliek U oil was performed. Fatty acids were analyzed by gas chromatography-mass spectrometry (GC-MS), and pharmacological properties based on its potential on filament-aggregating protein (filaggrin) were studied with bioinformatics approach by the reverse docking technique using palmitic acid as a control compound. Two Pliek U extracts, namely, Pliek U oil (PUO) and ethanolic Pliek U oil extract (EPUOE), were prepared. The GC-MS results revealed that lauric acid, myristic acid, palmitic acid, and oleic acid are the predominant fatty acids, with lauric acid being the abundant one in all Pliek U oil extracts. The reverse docking technique results showed that oleic acid had the most stable interaction to filaggrin with the lowest binding affinity (-6.1 kcal/mol). Oleic acid and palmitic acid have one same side binding to filaggrin on amino acid LEU D75. These findings indicated that oleic acid has the best potential to be used as a drug candidate in atopic dermatitis treatment.


Assuntos
Anti-Inflamatórios/química , Óleo de Coco/química , Ácidos Graxos/química , Proteínas de Filamentos Intermediários/química , Simulação de Acoplamento Molecular , Anti-Inflamatórios/farmacologia , Sítios de Ligação , Ácidos Graxos/farmacologia , Proteínas Filagrinas , Proteínas de Filamentos Intermediários/metabolismo , Ligação Proteica
15.
J Med Econ ; 22(10): 1047-1054, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31298593

RESUMO

Background: The aim of this study is to estimate the budget impact of budesonide/formoterol fixed dose combination (FDC) vs salbutamol, both used as needed, in mild asthma patients, from the perspective of the Health Insurance Organization (HIO). Methods: A static budget impact model was developed to assess the impact of budesonide/formoterol FDC entry on HIO budget over a 3-year period in Egyptian settings. Direct medical costs, including the costs of asthma medications, exacerbations, and management of side-effects, were obtained from HIO cost data. Population data were obtained from the World Bank and supplemented with local studies, and the rates of exacerbations, adverse effects, and number of sick leave days were elicited from the SYGMA 1 trial. Scenario analyses from a societal perspective and deterministic sensitivity analyses were conducted. Results: The total costs (drug and non-drug costs) for managing mild asthma patients from the HIO perspective were estimated to be EGP8.563 billion before budesonide/formoterol entry compared to EGP5.525 billion post-entry, leading to a total budget savings of EGP3.038 billion after 3 years. This total budget saving included an increase in drug costs (EGP104 million) and a decrease in non-drug costs (EGP3.143 billion). Drug costs were higher in the budesonide/formoterol group than in the salbutamol group, but this cost was offset by reductions in non-drug costs, resulting in a reduction in the total costs of healthcare resources. At the societal level, the total budget savings after including the indirect costs was expected to be EGP5.976 billion after 3 years of budesonide/formoterol entry. Conclusion: Budesonide/formoterol in mild asthma instead of salbutamol produces better patient outcomes and decreases total costs, with increases in drug cost offset by reductions in non-drug costs due to fewer exacerbations. Budesonide/formoterol is a budget saving option for guideline-directed treatment, from the economic perspective of the payer and the health perspective of the patient.


Assuntos
Asma/tratamento farmacológico , Broncodilatadores/economia , Budesonida/economia , Orçamentos , Fumarato de Formoterol/economia , Asma/epidemiologia , Asma/fisiopatologia , Broncodilatadores/uso terapêutico , Budesonida/uso terapêutico , Análise Custo-Benefício , Bases de Dados Factuais , Custos de Medicamentos , Egito/epidemiologia , Fumarato de Formoterol/uso terapêutico , Humanos , Prevalência
16.
Langmuir ; 35(25): 8246-8256, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31132272

RESUMO

CeO2 nanoparticle-decorated ?-MnO2 nanotubes (NTs) were prepared and tested for elemental mercury (Hg0) vapor removal in simulated natural gas mixtures at ambient conditions. The composition which had the largest surface area and a relative Ce/Mn atomic weight ratio of around 35% exhibited a maximum Hg0 uptake capacity exceeding 20 mg?g?1 (2 wt %), as determined from measurements of mercury breakthrough which corresponded to 99.5% Hg0 removal efficiency over 96 h of exposure. This represents a significant improvement in the activity of pure metal oxides. Most importantly, the composite nanosorbent was repeatedly regenerated at 350 ?C and retained the 0.5% Hg0 breakthrough threshold. It was projected to be able to sustain 20 regeneration cycles, with the presence of acid gases, CO2, and H2S, not affecting its performance. This result is particularly important, considering that pure CeO2 manifests rather poor activity for Hg0 removal at ambient conditions, and hence, a synergistic effect in the composite nanomaterial was observed. This possibly results from the addition of facile oxygen vacancy formation at ?-MnO2 NTs and the increased amount of surface-adsorbed oxygen species.

17.
J Orthop Surg (Hong Kong) ; 27(2): 2309499019840083, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30955449

RESUMO

Cardiac arrest during scoliosis surgery is rare in idiopathic scoliosis. We present a case of cardiorespiratory collapse during corrective surgery in a young patient with idiopathic scoliosis. A diagnosis of venous air embolism was made by exclusion. A cardiorespiratory resuscitation was performed in supine position. Patient recovered without any sequelae and had operation completed 6 weeks later.


Assuntos
Embolia Aérea/complicações , Parada Cardíaca/etiologia , Complicações Intraoperatórias , Embolia Pulmonar/complicações , Escoliose/cirurgia , Fusão Vertebral/efeitos adversos , Reanimação Cardiopulmonar/métodos , Angiografia por Tomografia Computadorizada , Ecocardiografia , Embolia Aérea/diagnóstico , Feminino , Parada Cardíaca/diagnóstico , Parada Cardíaca/terapia , Humanos , Vértebras Lombares/cirurgia , Embolia Pulmonar/diagnóstico , Vértebras Torácicas/cirurgia , Adulto Jovem
18.
Mater Sci Eng C Mater Biol Appl ; 96: 286-294, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30606534

RESUMO

Manufacturing nanoparticles with controlled physicochemical properties using environment-friendly routes have potential to open new prospects for a variety of applications. Accordingly, several approaches have been established for manufacturing metal nanoparticles. Many of these approaches entail the use of hazardous chemicals and could be toxic to the environment, and cannot be used readily for biomedical applications. In the present work, we report a single step bio-friendly approach to formulate gold (Au), silver (Ag), and Au-Ag alloy nanoparticles with desired surface corona and composition using isonicotinylhydrazide (INH) as a reducing agent. INH also functioned as a stabilizing agent by enabling a surface corona around the nanoparticles. Remarkably, within a single step INH could also provide a handle in regulating the composition of Au and Ag in bimetallic systems without any additional chemical modification. The physicochemical and surface properties of the different nanoparticles thus obtained have been examined by analytical, spectroscopic and microscopic techniques. Cell cytotoxicity (release of lactate dehydrogenase), cell viability and intracellular reactive oxygen species (ROS) assays confirmed that the Au, Ag, and Au-Ag bimetallic nanoparticles prepared with INH are biocompatible. Finally, the presence of organic surface corona of INH on the nanoparticles was found to impart nanozyme activity and antimycobacterial sensitivity to the nanoparticles.


Assuntos
Ligas/química , Fibroblastos/metabolismo , Ouro/química , Hidrazinas/química , Teste de Materiais , Nanopartículas Metálicas/química , Prata/química , Animais , Células Cultivadas , Fibroblastos/citologia , Camundongos , Oxirredução
19.
PLoS One ; 13(11): e0206982, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30399167

RESUMO

BACKGROUND: The resistance problem of dengue vectors to different classes of insecticides that are used for public health has raised concerns about vector control programmes. Hence, the discovery of alternative compounds that would enhance existing tools is important for overcoming the resistance problem of using insecticides in vectors and ensuring a chemical-free environment. The larvicidal effects of Azolla pinnata extracts by using two different extraction methods with methanol solvent against Aedes in early 4th instar larvae was conducted. METHODS: The fresh Azolla pinnata plant from Kuala Krai, Kelantan, Malaysia was used for crude extraction using Soxhlet and maceration methods. Then, the chemical composition of extracts and its structure were identified using GCMS-QP2010 Ultra (Shimadzu). Next, following the WHO procedures for larval bioassays, the extracts were used to evaluate the early 4th instar larvae of Aedes mosquito vectors. RESULTS: The larvicidal activity of Azolla pinnata plant extracts evidently affected the early 4th instar larvae of Aedes aegypti mosquito vectors. The Soxhlet extraction method had the highest larvicidal effect against Ae. aegypti early 4th instar larvae, with LC50 and LC95 values of 1093 and 1343 mg/L, respectively. Meanwhile, the maceration extraction compounds were recorded with the LC50 and LC95 values of 1280 and 1520 mg/L, respectively. The larvae bioassay test for Ae. albopictus showed closely similar values in its Soxhlet extraction, with LC50 and LC95 values of 1035 and 1524 mg/L, compared with the maceration extraction LC50 and LC95 values of 1037 and 1579 mg/L, respectively. The non-target organism test on guppy fish, Poecilia reticulata, showed no mortalities and posed no toxic effects. The chemical composition of the Azolla pinnata plant extract has been found and characterized as having 18 active compounds for the Soxhlet method and 15 active compounds for the maceration method. CONCLUSIONS: Our findings showed that the crude extract of A. pinnata bioactive molecules are effective and have the potential to be developed as biolarvicides for Aedes mosquito vector control. This study recommends future research on the use of active ingredients isolated from A. pinnata extracts and their evaluation against larvicidal activity of Aedes in small-scale field trials for environmentally safe botanical insecticide invention.


Assuntos
Aedes/efeitos dos fármacos , Gleiquênias/química , Inseticidas/química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Animais , Bioensaio , Cromatografia Gasosa-Espectrometria de Massas , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Testes de Toxicidade
20.
J Parasitol Res ; 2018: 1383186, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30050688

RESUMO

Dengue is vector-borne diseases with 390 million infections per year extending over 120 countries of the world. Aedes aegypti (L.) (Diptera: Culicidae) is a primary vector for dengue viral infections for humans. Current focus on application of natural product against mosquito vectors has been the main priority for research due to its eco-safety. The extensive use of chemical insecticides has led to severe health problems, environmental pollution, toxic hazards to human and nontarget species, and development of insecticide resistance on mosquitoes. Azolla pinnata is an aquatic fern and predominantly used as feed in poultry industry and as fertilizer in agricultural field for enhancing the fertility of rice paddy soil. The present study was conducted to explore the larvicidal efficacy of A. pinnata using fresh and powdered form against late third-stage larvae (6 days, 5 mm in larvae body length) of Ae. aegypti (L.) (Diptera: Culicidae). The larvicidal bioassays were performed using World Health Organization standard larval susceptibility test method for different concentration for powdered and fresh A. pinnata. Powdered A. pinnata concentration used during larvicidal bioassay ranges from 500ppm to 2000ppm; meanwhile, fresh A. pinnata ranges from 500ppm to 9,000,000 ppm. The highest mortality was at 1853 ppm for powdered A. pinnata compared with fresh A. pinnata at 2,521,535 ppm, while the LC50 for both powdered and fresh A. pinnata recorded at 1262 ppm and 1853 ppm, respectively. Finally, the analysis of variance (ANOVA) showed significant difference on Ae. aegypti larval mortality (F=30.439, df=1, p≤0.001) and concentration (F=20.002, df=1, p≤0.001) compared to powdered and fresh A. pinnata at 24-hour bioassay test. In conclusion, the powdered A. pinnata serves as a good larvicidal agent against Ae. aegypti (L.) (Diptera: Culicidae) and this study provided information on the lethal concentration that may have potential for a more eco-friendly Aedes mosquito control program.

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