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1.
J Biomol Struct Dyn ; 41(22): 13415-13424, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36752377

RESUMO

Tyrosine-protein kinase CSK otherwise known as C-terminal Src kinase (CSK), is involved in multiple pathways and processes, including regulating cell growth, differentiation, migration, and immune responses. Altered expression of CSK has been associated with various complexities, including cancer, CD45 deficiency, Osteopetrosis and lupus erythematosus. Important auxiliary roles of CSK in cancer progression make it a crucial target in developing novel anticancer therapy. Thus, CSK inhibitors are of concern as potent immuno-oncology agents. In this perspective, phytochemicals can be a significant source for unraveling novel CSK inhibitors. In this study, we carried out a systematic structure-based virtual screening of bioactive phytoconstituents against CSK to identify its potential inhibitors. After a multi-step screening process, two hits (Shinpterocarpin and Justicidin B) were selected based on their druglike properties and binding affinity towards CSK. The selected hits were further analyzed for their stability and interaction via all-atom molecular dynamics (MD) simulations. The selected hits indicated their potential as selective binding partners of CSK, which can further be used for therapeutic development against CSK-associated malignancies.Communicated by Ramaswamy H. Sarma.


Assuntos
Neoplasias , Quinases da Família src , Humanos , Proteína Tirosina Quinase CSK/metabolismo , Quinases da Família src/metabolismo , Simulação de Dinâmica Molecular
2.
Bol. latinoam. Caribe plantas med. aromát ; 21(3): 365-388, mayo 2022. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1396918

RESUMO

Modifications of land use and vegetation cover are proceeding faster than ever before in human history, with a considerable reduction in forest cover in biodiversity hotspots. We investigated the land use and vegetation cover changes, their impact on biodiversity in the Kurram District, Pakistan, for 27 years (1989 to 2015). Temporal satellite imagery was processed using a supervised maximum likelihood classification algorithm in ARCGIS 10.1 to elucidate information regarding land use/land cover changes,with conducted structured interviews to obtain the inhabitants' perspectives on their dependence on ecosystems in Kurram, and how their environment is changing. We found that the land under forest cover and rangeland showed a remarkable decrease over the study period. This decline in rangeland and forest cover was a result of the increased of farmland, barren land. The study area is part of a biodiversity, with important medicinal, rare and unique plant species.


Las modificaciones del uso de la tierra y la cobertura vegetal están avanzando más rápido que nunca en la historia de la humanidad, con una reducción considerable de la cobertura forestal en los puntos críticos de biodiversidad. Investigamos el uso de la tierra y los cambios en la cobertura vegetal, su impacto en la biodiversidad en el distrito de Kurram, Pakistán, durante 27 años (1989 a 2015). Las imágenes satelitales temporales se procesaron utilizando un algoritmo de clasificación de máxima verosimilitud supervisada en ARCGIS 10.1 para dilucidar información sobre los cambios en el uso del suelo/cobertura del suelo, con entrevistas estructuradas realizadas para obtener las perspectivas de los habitantes sobre su dependencia de los ecosistemas en Kurram y cómo está cambiando su entorno. Descubrimos que la tierra cubierta por bosques y pastizales mostró una disminución notable durante el período de estudio. Esta disminución en los pastizales y la cubierta forestal fue el resultado del aumento de las tierras de cultivo, tierras estériles. El área de estudio es parte de una biodiversidad, con importantes especies de plantas medicinales, raras y únicas.


Assuntos
Usos do Solo , Exploração de Recursos Naturais , Biodiversidade , Paquistão , Pastagens , Ecossistema , Agricultura , Imagens de Satélites
3.
Biomed Res Int ; 2021: 9026731, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34912897

RESUMO

Investigation on medicinal plants' therapeutic potential has gained substantial importance in the discovery of novel effective and safe therapeutic agents. The present study is aimed at investigating the hepatoprotective potential of Seriphidium kurramense methanolic extract (SKM) against carbon tetrachloride- (CCl4-) induced hepatotoxicity in rats. S. kurramense is one of the most imperative plants for its various pharmacological activities. Therefore, this study was aimed at evaluating the hepatoprotective potential against CCl4-induced liver toxicity. The serum samples were analyzed for alanine aminotransferase (ALT) and aspartate aminotransferase (AST) together with the oxidative stress mediator levels as nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), reduced glutathione (GSH), and superoxide dismutase (SOD) as well as peroxidation and H2O2 activity. CCl4 administration resulted in an elevated free radical generation, altered liver marker (AST and ALT) enzymes, reduced antioxidant enzyme, and increased DNA damage. Methanolic extract of S. kurramense decreased CCl4-induced hepatotoxicity by increasing the antioxidant status and reducing H2O2 and nitrate content generation as well as reducing DNA damage. Additionally, SKM reversed the morphological alterations induced by CCl4 in the SKM-treated groups. These results demonstrated that SKM displayed hepatoprotective activity against CCl4-induced hepatic damage in experimental rats.


Assuntos
Artemisia/química , Fígado/efeitos dos fármacos , Preparações de Plantas/farmacologia , Substâncias Protetoras/farmacologia , Alanina Transaminase/metabolismo , Animais , Antioxidantes/metabolismo , Aspartato Aminotransferases/metabolismo , Tetracloreto de Carbono/farmacologia , Dano ao DNA/efeitos dos fármacos , Glutationa/metabolismo , Fígado/metabolismo , Malondialdeído/metabolismo , Programas de Rastreamento/métodos , Modelos Animais , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
4.
Microsc Res Tech ; 84(12): 3161-3170, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34288234

RESUMO

Soot particles emitted from the burning of solid fuel sources in the households carry important environmental and public health implications. In this study, the indoor soot particles released from firewood, cow dung, and bagasse burning at households of selected rural areas of Khyber Pakhtunkhwa province of Pakistan were investigated by characterization analyses to study its morphological and elemental compositions. Results demonstrated diverse compositions of soot particles from each fuel source. The surface areas of soot particles emitted by the firewood, cow dung, and bagasse were about 0.3, 0.4, and 8.64 m2  g-1 , respectively. For the soot particles emitted by the firewood burning, the major functional groups for aromatic compounds were C═C at the 1,431-1,599 at 1,000-2,000 cm-1 . The absorbance rate of alkanes was about 1,599-1,431 at 1,000-2,000 cm-1 . However, silicon band vibration was more prominent in bagasse soot particles as compared to other samples. The emission of soot particles with high surface area in the atmosphere could provide an elevated adsorption sites for atmospheric pollution and trap more energy resulting in increased atmospheric temperature. Findings from the present study suggest that current households' fuel combustion practices significantly contribute to increase the particulate matter in the atmosphere and possible enhance climate change phenomenon and related disasters in northern Pakistan.


Assuntos
Material Particulado , Fuligem , Paquistão , Material Particulado/análise , Fuligem/análise
5.
Biochim Biophys Acta Proteins Proteom ; 1867(3): 275-285, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30312771

RESUMO

Protein aggregation have been associated with several human neurodegenerative diseases, such as Parkinson's and Alzheimer's diseases. There are several small molecules that can reduce aggregation of proteins. The present study aimed to test the hypothesis that the application of more than one inhibitor either simultaneously or consecutively may result in more efficient inhibition of protein aggregation. To this end, the anti-amyloidogenic behaviour of benserazide hydrochloride (BH) and levodopa (LD) individually and in combination (BH + LD) was investigated using various biophysical, microscopic, and computational techniques. BH, LD, and BH + LD treatments showed inhibitory effects on protein aggregation and had the ability to minimise the amyloid-induced cytotoxicity in human neuroblastoma cell line (SH-SY5Y). The two drugs in combination showed synergism (combination index, CI < 1) between them. These drugs also destabilised the preformed fibrils of human serum albumin (HSA). Our studies consistently showed that the BH + LD treatment showed highest efficacy towards inhibition and disaggregation of amyloid fibrils in comparison to treatment with BH and LD individually. Therefore, application of drugs in combination against fibrillogenesis may represent a new route for development of means for prevention or delaying of the aggregation-related diseases.


Assuntos
Amiloide/metabolismo , Benserazida/farmacologia , Dopaminérgicos/farmacologia , Levodopa/farmacologia , Agregados Proteicos/efeitos dos fármacos , Albumina Sérica Humana/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Combinação de Medicamentos , Humanos , Doença de Parkinson/tratamento farmacológico
6.
Recent Pat Anticancer Drug Discov ; 14(2): 133-143, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30451116

RESUMO

BACKGROUND: Cucurbitacins belong to a group of tetracyclic triterpenoids that display a wide range of biological effects. In the past, numerous cucurbitacins have been isolated from natural sources and many active compounds have been synthesized using the privileged scaffold in order to enhance its cytotoxic effects. OBJECTIVE: This review covers patents on the therapeutic effects of natural cucurbitacins and their synthetic analogs published during the past decade. By far, the majority of patents published are related to cancer and Structure-Activity Relationships (SAR) of these compounds are included to lend gravitas to this important class of natural products. METHODS: The date about the published patents was downloaded via online open access patent databases. RESULTS: Cucurbitacins display significant cytotoxic properties, in particular cucurbitacins B and D which possess very potent effects towards a number of cancer cells. Numerous cucurbitacins isolated from natural sources have been derivatized through chemical modification at the C(2)-OH and C(25)- OH groups. Most importantly, an acyl ester of the C(25)-OH and, iso-propyl, n-propyl and ethyl ether groups of the C(2)-OH demonstrated the most increased cytotoxic activity. CONCLUSION: The significant cytotoxic effects of natural and semi-synthetic cucurbitacins make them attractive as new drug candidates. Moreover, cucurbitacins have the capability to form conjugates with other anticancer drugs which will synergistically enhance their anticancer effects. The authors believe that in order to get lead compounds, there should be a greater focus on the synthesis of homodimers, heterodimers, and halo derivatives of cucurbitacins. In the opinion of the authors the analysis of the published patents on the cucurbitacins indicates that these compounds can be developed into a regimen to treat a wide spectrum of cancers.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Cucurbitacinas/uso terapêutico , Neoplasias/tratamento farmacológico , Patentes como Assunto , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/classificação , Cucurbitacinas/química , Cucurbitacinas/classificação , Cucurbitacinas/economia , Desenho de Fármacos , Humanos , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/economia , Triterpenos/uso terapêutico
7.
Micron ; 111: 36-49, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29857176

RESUMO

Dryopteris and Polystichum are the 2 complex taxonomic genera of Dryopteridaceae. The comparative foliar epidermal anatomy of 12 species of both genera from Pakistan were studied using standard protocols of light microscopy (LM) and scanning electron microscopy (SEM). The objective of which was systematic comparison and investigation to elucidate the taxonomic importance of foliar micromorphology, which may be useful to taxonomists for identifying complex Dryopteridaceae taxa. Principal component analysis and UPGMA clustering analysis were performed to test the validity of leaf anatomical features as method of separating species and genera. The foliar epidermal anatomy described here is a good source of taxonomic characters in both groups that can help genera and species delimitation. This is the first report on leaf micromorphology in most of these species. Observation of foliar anatomy showed that stomata are only present on the abaxial surface; i.e., leaves of all species are hypostomatic. The shapes of epidermal cells in all studied species are irregular. The anticlinal walls are strongly lobed, irregular wavy and elongated wavy. However, substantial variation in epidermal cell size and other stomatal features were observed on both upper and lower surfaces in all investigated species. Two types of stomata were observed in all studied species. The presence of polocytic stomata in Dryopteris and staurocytic stomata in Polystichum are the important characters for the segregation of these genera. Elongate elliptic stomatal shape, narrow kidney shaped guard cells and broad elliptic shaped stomatal pores are diagnostic for all five species of Dryopteris selected. On the other hand, size and number of epidermal cells, lobes per cell, stomatal size, subsidiary cell size, stomatal pore size and stomatal index are the key features for species differentiation in Polystichum. An identification key was developed in order to apply the foliar anatomical characters in the discrimination of the species studied.


Assuntos
Dryopteris/ultraestrutura , Epiderme Vegetal/ultraestrutura , Folhas de Planta/anatomia & histologia , Folhas de Planta/ultraestrutura , Polystichum/ultraestrutura , Dryopteris/anatomia & histologia , Dryopteris/classificação , Paquistão , Estômatos de Plantas/ultraestrutura , Polystichum/anatomia & histologia , Polystichum/classificação , Análise de Componente Principal
8.
Artigo em Inglês | MEDLINE | ID: mdl-24280298

RESUMO

The potentially green solvents made up of ionic liquids (ILs) and poly(ethylene glycols) may have wide range of the applications in many chemical and biochemical fields. In the present work, solvatochromic absorbance probe behaviour is used to assess the physicochemical properties of the mixtures composed of PEG-400+IL, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [bmim][Tf2N]. Lowest energy intramolecular charge-transfer absorbance maxima of a betaine dye, i.e., E(T)(N), indicates the dipolarity/polarizability and/or hydrogen-bond donating (HBD) acidity of the [bmim][Tf2N]+PEG-400 mixtures to be even higher than that of neat [bmim][Tf2N], the solution component with higher dipolarity/polarizability and/or HBD acidity. Dipolarity/polarizability (π(∗)) obtained separately from the electronic absorbance response of probe N,N-diethyl-4-nitroaniline, and the HBD acidity (α) of PEG-400+[bmim][Tf2N] mixtures are also observed to be anomalously high. A comparative study of the PEG+IL mixtures has also been done with PEG-400+molecular organic solvents (protic polar [methanol], aprotic polar [N,N-dimethylformamide], and non polar, [benzene]) mixtures, but these mixtures do not show this type of unusual behaviour. A four-parameter simplified combined nearly ideal binary solvent/Redlich-Kister (CNIBS/R-K) equation is shown to satisfactorily predict the solvatochromic parameters within PEG-400+different solvent mixtures.


Assuntos
Líquidos Iônicos/química , Sondas Moleculares/química , Polietilenoglicóis/química , Solventes/química , Absorção , Imidazóis/química , Modelos Químicos , Sulfonamidas
9.
J Phys Chem B ; 113(10): 3088-98, 2009 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-19260713

RESUMO

In this work, an array of molecular-level solvent features--including solute--solvent/solvent--solvent interactions, dipolarity, heterogeneity, dynamics, probe accessibility, and diffusion--were investigated across the entire composition of ambient mixtures containing the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate, [bmim][BF4], and pH 7.0 phosphate buffer, based on results assembled for nine different molecular probes utilized in a range of spectroscopic modes. These studies uncovered interesting and unusual solvatochromic probe behavior within this benchmark mixture. Solvatochromic absorbance probes--a water-soluble betaine dye (betaine dye 33), N,N-diethyl-4-nitroaniline, and 4-nitroaniline--were employed to determine ET (a blend of dipolarity/polarizability and hydrogen bond donor contributions) and the Kamlet-Taft indices pi* (dipolarity/polarizability), alpha (hydrogen bond donor acidity), and beta (hydrogen bond acceptor basicity) characterizing the [bmim][BF4] + phosphate buffer system. These parameters each showed a marked deviation from ideality, suggesting selective solvation of the individual probe solutes by [bmim][BF4]. Similar conclusions were derived from the responses of the fluorescent polarity-sensitive probes pyrene and pyrene-1-carboxaldehyde. Importantly, the fluorescent microfluidity probe 1,3-bis(1-pyrenyl)propane senses a microviscosity within the mixture that significantly exceeds expectations derived from simple interpolation of the behavior in the neat solvents. On the basis of results from this probe, a correlation between microviscosity and bulk viscosity was established; pronounced solvent-solvent hydrogen-bonding interactions were implicit in this behavior. The greatest deviation from ideal additive behavior for the probes studied herein was consistently observed to occur in the buffer-rich regime. Nitromethane-based fluorescence quenching of pyrene within the [bmim][BF4] + phosphate buffer system showed unusual compliance with a "sphere-of-action" quenching model, a further manifestation of the microheterogeneity of the system. Fluorescence correlation spectroscopic results for both small (BODIPY FL) and macromolecular (Texas Red-10 kDa dextran conjugate) diffusional probes provide additional evidence in support of microphase segregation inherent to aqueous [bmim] [BF4].


Assuntos
Imidazóis/química , Espectrofotometria/métodos , Betaína/química , Soluções Tampão , Físico-Química/métodos , Corantes/farmacologia , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Metano/análogos & derivados , Metano/química , Modelos Estatísticos , Nitroparafinas/química , Fosfatos/química , Solubilidade , Soluções , Solventes/química , Espectrometria de Fluorescência/métodos
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