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1.
Environ Geochem Health ; 46(4): 128, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483731

RESUMO

Extreme climates and the unpredictability of the weather are significant obstacles to agricultural productivity. This study is the first attempt to explore the capacity of nanobonechar (NBC) for promoting climate-smart agriculture. A pot experiment was performed on maize (Zea mays L.) under a deficit irrigation system (40, 70, and 100% irrigation rates) using different soil application rates of the NBC (0, 0.5, 1, and 2% wt/wt). Additionally, the CO2-C efflux rate and cumulative CO2-C were measured in an incubation experiment. The results indicated the best performance of the 1% NBC treatment under a 70% irrigation rate in terms of the fresh and dry weights of maize plants. Total PO43- and Ca2+ were significantly higher in the plants grown in the NBC-amended soil as compared to the control, showing a gradual increase with an increase in the NBC application rate. The improved productivity of maize plants under a deficit irrigation system was associated with enhanced water-holding capacity, organic matter, and bioavailability of cations (Ca2+, K+, and Na+) and anions (PO43- and NO3-) in the soils amended with NBC. The CO2-C efflux rate and cumulative CO2-C emissions remain higher in the NBC-amended soil than in the un-amended soil, pertaining to the high contents of soil organic matter emanating from the NBC. We conclude that NBC could potentially be used as a soil amendment for promoting maize growth under a water stress condition.


Assuntos
Agricultura , Dióxido de Carbono , Dióxido de Carbono/análise , Solo , Clima , Zea mays
2.
Environ Res ; 251(Pt 2): 118695, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38493857

RESUMO

The use of nanotechnology in terms of nanoparticles, carbon nanotubes, and quantum dots, when exposed to the plants, helps increase their productivity. It is worth the effort to comprehend the fate of these nanoparticles in plants. Bonechar derived from bones is a rich source of C, P, Ca2+, and Mg2+ nutrients, which can significantly contribute to the growth of the plants. This study focused on the uptake of nano-bonechar (NBC) in the Syngonium podophyllum plant, and its effects on plant growth under hydroponics and soil systems. The compound microscopy and SEM-EDX results confirmed the presence of NBC in the leaves and roots of the plants in hydroponics and soil systems. The FTIR spectra reflected the presence of functional groups of the NBC in the leaves of the Syngonium podophyllum plant. The plant's growth parameters showed an increase in fresh weight, dry weight, shoot length, chlorophyll content, leaf count, total Ca2+, total PO43-, and total organic carbon of plants in both systems. The NBC not just improved plant physiochemical parameters but also built up the soil quality in terms of bioavailable Ca2+, PO43-, water holding capacity, and soil organic matter. It is concluded that the production of carbon-based NBC not only helps manage bone waste but also their efficient uptake in plants significantly improving plant productivity.

3.
Chemosphere ; 353: 141490, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38417494

RESUMO

Fluoride ion (F-) is one of the major geogenic contaminants in water and soil. Excessive consumption of these geogenic contaminants poses serious health impacts on humans and plants. In this study, a novel carbonaceous material, nano-bonechar, was synthesized from cow bones and applied as a soil amendment at rates of 0, 0.5, 1, and 2% to remediate and revitalize naturally F--contaminated soil. The results revealed that the nano-bonechar significantly reduced the mobility and bioavailability of F- by 90% in the contaminated soil, and improved the soil quality by increasing the soil water holding capacity, soil organic matter, and the bioavailable contents of PO43-, Ca2+, and Na+. Subsequently, the pot experiment results showed a significant reduction in the uptake of F- by 93% in Zea mays plants. Moreover, the nano-bonechar application improved the plant's growth, as indicated by the higher fresh and dry weights, root and shoot lengths, and total content of PO43-, Ca2+, and K+ than those of un-amended soil. The F-immobilization in soil was mainly due to the presence of the hydroxyapatite [Ca10(PO4)6(OH)2] mineral in the nano-bonechar. Ion exchange between OH- (of nano-bonechar) and F- (of soil), and the formation of insoluble fluorite (CaF2) contributed to the attenuation of F- mobility in the soil. It is concluded that nano-bonechar, due to its size and enrichment in hydroxyapatite, could successfully be utilized for the rapid remediation and revitalization of F--contaminated agricultural soil.


Assuntos
Fluoretos , Poluentes do Solo , Humanos , Poluentes do Solo/análise , Solo , Água , Hidroxiapatitas
4.
J Biomol Struct Dyn ; 42(7): 3700-3711, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37222604

RESUMO

Lysosomal enzymes degrade cellular macromolecules, while their inactivation causes human hereditary metabolic disorders. Mucopolysaccharidosis IVA (MPS IVA; Moquio A syndrome) is one of the lysosomal storage disorders caused by a defective Galactosamine-6-sulfatase (GalN6S) enzyme. In several populations, disease incidence is elevated due to missense mutations brought on by non-synonymous allelic variation in the GalN6S enzyme. Here, we studied the effect of non-synonymous single nucleotide polymorphism (nsSNPs) on the structural dynamics of the GalN6S enzyme and its binding with N-acetylgalactosamine (GalNAc) using all-atom molecular dynamics simulation and an essential dynamics approach. Consequently, in this study, we have identified three functionally disruptive mutations in domain-I and domain-II, that is, S80L, R90W, and S162F, which presumably contribute to post-translational modifications. The study delineated that both domains work cooperatively, and alteration in domain II (S80L, R90W) leads to conformational changes in the catalytic site in domain-I, while mutation S162F mainly provokes higher residual flexibility of domain II. These results show that these mutations impair the hydrophobic core, implying that Morquio A syndrome is caused by misfolding of the GalN6S enzyme. The results also show the instability of the GalN6S-GalNAc complex upon substitution. Overall, the structural dynamics resulting from point mutations give the molecular rationale for Moquio A syndrome and, more importantly, the Mucopolysaccharidoses (MPS) family of diseases, re-establishing MPS IVA as a protein-folding disease.Communicated by Ramaswamy H. Sarma.


Assuntos
Mucopolissacaridose IV , Humanos , Mucopolissacaridose IV/genética , Acetilgalactosamina , Galactosamina , Dobramento de Proteína , Sulfatases
5.
J Mech Behav Biomed Mater ; 150: 106268, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38039776

RESUMO

Chitosan (Ch) is a naturally occurring biocompatible and bio-degradable material with high corrosion protective capacities for metals in various corrosive media. Hydroxyapatite (HA) is a significant biodegradable and bioactive material. In the present work, chitosan-hydroxyapatite (Ch-HA) composite coatings with various concentrations of chitosan were made on 316L stainless steel (316L SS) using sol-gel dip coating technique. The coatings were characterized by X-ray diffraction (XRD), FTIR, SEM, and electrochemical measurements. The surface morphology results (SEM) of coated implants exposed the fairly dense microstructures having uniformity without cracks and pores indicating that coating was successfully deposited. From electrochemical analyses, it was observed that the value of corrosion current density and the corrosion rate decreased from 6.03 to 0.15 and 5.56-0.13 respectively indicating that 1.5gCh-HA is the best coating concentration. The electrochemical results demonstrated an improvement in the corrosion resistance of 316L SS than the bare one. The decrease in slope and loop area of cyclic voltammograms reveals about improvement in corrosion resistance. This increment in corrosion resistance of the Ch-HA coated SS implant in the artificial saliva is as 1.5gCh-HA > 2gCh-HA >1gCh-HA >0.5gCh-HA. Furthermore, Ch-HA coatings revealed appropriate adhesion with 316L SS substrate for its use in dental implants.


Assuntos
Quitosana , Implantes Dentários , Durapatita/química , Materiais Revestidos Biocompatíveis/química , Corrosão , Teste de Materiais , Propriedades de Superfície
6.
J Mech Behav Biomed Mater ; 148: 106202, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37890342

RESUMO

Ternary ceramic samples comprising SrO-MgO-SiO2 with varying element concentrations were synthesized using the solid-state method and sintered at 800°C. To characterize the properties of the samples, several analysis techniques were employed. X-ray Diffraction (XRD) was utilized for structural analysis, FTIR spectroscopy was used to identify bonds, SEM provided morphological analysis, biocompatibility was assessed through Vitro testing, microhardness was evaluated using Vickers testing, and dielectric analysis was performed to investigate electrical properties. The XRD spectra confirmed the presence of a ternary phase known as Magnesium Strontium Di-silicate [MgSr2Si2O7], with no impurity peaks detected. FTIR spectroscopy indicated the formation of Magnesium silicate, displaying vibrational bands corresponding to SiO4 and MgO, which further confirmed the existence of MgSr2Si2O7 in the samples. The Vitro test results revealed that all samples exhibited biocompatible behavior, with moderate pH and weight loss. SEM images provided insights into the morphology of the system and confirmed the development of an appetite layer on the sample surfaces. The particle size of the samples was measured to be approximately 116.48±9 nm. Vickers hardness testing yielded microhardness values ranging from 378.1 to 400.2 HV. Dielectric constant measurements demonstrated that the AC conductivity of the SrO-MgO-SiO2 system increased as the percentage of Mg doping increased.


Assuntos
Óxido de Magnésio , Dióxido de Silício , Óxido de Magnésio/química , Dióxido de Silício/química , Silicatos , Dureza , Magnésio
7.
Viruses ; 15(2)2023 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-36851785

RESUMO

Monkeypox is a serious public health issue in tropical and subtropical areas. Antivirals that target monkeypox proteins might lead to more effective and efficient therapy. The F13 protein is essential for the growth and maturation of the monkeypox virus. F13 inhibition might be a viable therapeutic target for monkeypox. The in silico fragment-based drug discovery method for developing antivirals may provide novel therapeutic options. In this study, we generated 800 compounds based on tecovirimat, an FDA-approved drug that is efficacious at nanomolar quantities against monkeypox. These compounds were evaluated to identify the most promising fragments based on binding affinity and pharmacological characteristics. The top hits from the chemical screening were docked into the active site of the F13 protein. Molecular dynamics simulations were performed on the top two probable new candidates from molecular docking. The ligand-enzyme interaction analysis revealed that the C2 ligand had lower binding free energy than the standard ligand tecovirimat. Water bridges, among other interactions, were shown to stabilize the C2 molecule. Conformational transitions and secondary structure changes in F13 protein upon C2 binding show more native three-dimensional folding of the protein. Prediction of pharmacological properties revealed that compound C2 may be promising as a drug candidate for monkeypox fever. However, additional in vitro and in vivo testing is required for validation.


Assuntos
Monkeypox virus , Mpox , Humanos , Ligantes , Simulação de Acoplamento Molecular , Antivirais/farmacologia , Benzamidas , Isoindóis
8.
BMJ Case Rep ; 12(12)2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31796435

RESUMO

Tetanus remains a significant cause of mortality especially in the developing world. Early diagnosis and institution of treatment is critical to prevent fatal complications. The diagnosis is made on clinical grounds, which may sometimes be difficult, especially in case of localised tetanus. Being able to diagnose tetanus objectively is invaluable in such cases. In this regard, masseter inhibitory reflex (MIR) is a simple neurophysiological test that can be performed at the bedside. Herein, we report a case of craniocervical tetanus that was objectively diagnosed using MIR and adequately treated.


Assuntos
Músculo Masseter/inervação , Reflexo , Tétano/diagnóstico , Adulto , Estimulação Elétrica , Humanos , Masculino
9.
BMJ Case Rep ; 12(10)2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31604723

RESUMO

Chikungunya viral (CHIKV) fever is often a self-limiting febrile illness associated with severe debilitating arthralgia. Neurological complications associated with CHIKV, although rare, have been reported in literature; however, longitudinally extensive transverse myelitis (LTEM) is rarely associated with it. We present a case of a middle-aged man with a 1-week history of low-grade fever and arthralgia followed by urinary retention and quadriplegia. A sensory level was noted at T2. On subsequent investigations, he was diagnosed with LETM. Although LETM is commonly seen in patients with neuromyelitis optica, the other possible etiologies are inflammatory and parainfectious. To date, only two cases of LETM are reported worldwide in association with CHIKV fever and this is the first case from Pakistan. With frequent chikungunya outbreaks, neurological complications are increasingly seen in clinical practice. The knowledge of these associations will result in their early diagnosis and treatment.


Assuntos
Febre de Chikungunya/complicações , Encefalite/virologia , Mielite Transversa/virologia , Adulto , Artralgia , Febre de Chikungunya/diagnóstico por imagem , Febre de Chikungunya/tratamento farmacológico , Diagnóstico Diferencial , Encefalite/diagnóstico por imagem , Encefalite/tratamento farmacológico , Glucocorticoides/uso terapêutico , Humanos , Imageamento por Ressonância Magnética , Masculino , Metilprednisolona/uso terapêutico , Mielite Transversa/diagnóstico por imagem , Mielite Transversa/tratamento farmacológico , Paquistão
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