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1.
Proc Natl Acad Sci U S A ; 121(23): e2315363121, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38805281

RESUMO

Regulatory T cells (Tregs) are central in controlling immune responses, and dysregulation of their function can lead to autoimmune disorders or cancer. Despite extensive studies on Tregs, the basis of epigenetic regulation of human Treg development and function is incompletely understood. Long intergenic noncoding RNAs (lincRNA)s are important for shaping and maintaining the epigenetic landscape in different cell types. In this study, we identified a gene on the chromosome 6p25.3 locus, encoding a lincRNA, that was up-regulated during early differentiation of human Tregs. The lincRNA regulated the expression of interleukin-2 receptor alpha (IL2RA), and we named it the lincRNA regulator of IL2RA (LIRIL2R). Through transcriptomics, epigenomics, and proteomics analysis of LIRIL2R-deficient Tregs, coupled with global profiling of LIRIL2R binding sites using chromatin isolation by RNA purification, followed by sequencing, we identified IL2RA as a target of LIRIL2R. This nuclear lincRNA binds upstream of the IL2RA locus and regulates its epigenetic landscape and transcription. CRISPR-mediated deletion of the LIRIL2R-bound region at the IL2RA locus resulted in reduced IL2RA expression. Notably, LIRIL2R deficiency led to reduced expression of Treg-signature genes (e.g., FOXP3, CTLA4, and PDCD1), upregulation of genes associated with effector T cells (e.g., SATB1 and GATA3), and loss of Treg-mediated suppression.


Assuntos
Fatores de Transcrição Forkhead , Subunidade alfa de Receptor de Interleucina-2 , RNA Longo não Codificante , Linfócitos T Reguladores , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Subunidade alfa de Receptor de Interleucina-2/genética , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Epigênese Genética , Regulação da Expressão Gênica , Diferenciação Celular/genética
2.
Bioinformatics ; 40(6)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38867698

RESUMO

MOTIVATION: Molecular dynamics (MD) is a computational experiment that is crucial for understanding the structure of biological macro and micro molecules, their folding, and the inter-molecular interactions. Accurate knowledge of these structural features is the cornerstone in drug development and elucidating macromolecules functions. The open-source GROMACS biomolecular MD simulation program is recognized as a reliable and frequently used simulation program for its precision. However, the user requires expertise, and scripting skills to carrying out MD simulations. RESULTS: We have developed an end-to-end interactive MD simulation application, MolDy for Gromacs. This front-end application provides a customizable user interface integrated with the Python and Perl-based logical backend connecting the Linux shell and Gromacs software. The tool performs analysis and provides the user with simulation trajectories and graphical representations of relevant biophysical parameters. The advantages of MolDy are (i) user-friendly, does not requiring the researcher to have prior knowledge of Linux; (ii) easy installation by a single command; (iii) freely available for academic research; (iv) can run with minimum configuration of operating systems; (v) has valid default prefilled parameters for beginners, and at the same time provides scope for modifications for expert users. AVAILABILITY AND IMPLEMENTATION: MolDy is available freely as compressed source code files with user manual for installation and operation on GitHub: https://github.com/AIBResearchMolDy/Moldyv01.git and on https://aibresearch.com/innovations.


Assuntos
Simulação de Dinâmica Molecular , Software , Interface Usuário-Computador
3.
J Cell Mol Med ; 28(8): e18302, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38652115

RESUMO

The evolving landscape of personalized medicine necessitates a shift from traditional therapeutic interventions towards precision-driven approaches. Embracing this paradigm, our research probes the therapeutic efficacy of the aqueous crude extract (ACE) of Calocybe indica in cervical cancer treatment, merging botanical insights with advanced molecular research. We observed that ACE exerts significant influences on nuclear morphology and cell cycle modulation, further inducing early apoptosis and showcasing prebiotic attributes. Characterization of ACE have identified several phytochemicals including significant presence of octadeconoic acid. Simultaneously, utilizing advanced Molecular Dynamics (MD) simulations, we deciphered the intricate molecular interactions between Vascular Endothelial Growth Factor (VEGF) and Octadecanoic acid to establish C.indica's role as an anticancer agent. Our study delineates Octadecanoic acid's potential as a robust binding partner for VEGF, with comprehensive analyses from RMSD and RMSF profiles highlighting the stability and adaptability of the protein-ligand interactions. Further in-depth thermodynamic explorations via MM-GBSA calculations reveal the binding landscape of the VEGF-Octadecanoic acid complex. Emerging therapeutic innovations, encompassing proteolysis-targeting chimeras (PROTACs) and avant-garde nanocarriers, are discussed in the context of their synergy with compounds like Calocybe indica P&C. This convergence underscores the profound therapeutic potential awaiting clinical exploration. This study offers a holistic perspective on the promising therapeutic avenues facilitated by C. indica against cervical cancer, intricately woven with advanced molecular interactions and the prospective integration of precision therapeutics in modern oncology.


Assuntos
Simulação de Dinâmica Molecular , Extratos Vegetais , Neoplasias do Colo do Útero , Fator A de Crescimento do Endotélio Vascular , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Humanos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Feminino , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Medicina de Precisão/métodos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Ligação Proteica , Simulação de Acoplamento Molecular
4.
J Cell Mol Med ; 28(9): e18263, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685671

RESUMO

In the quest for effective lung cancer treatments, the potential of 3,6-diaminoacridine-9-carbonitrile (DAC) has emerged as a game changer. While DAC's efficacy against glioblastoma is well documented, its role in combating lung cancer has remained largely untapped. This study focuses on CTX-1, exploring its interaction with the pivotal EGFR-TKD protein, a crucial target in lung cancer therapeutics. A meticulous molecular docking analysis revealed that CTX-1 exhibits a noteworthy binding affinity of -7.9 kcal/mol, challenging Erlotinib, a conventional lung cancer medication, which displayed a binding affinity of -7.3 kcal/mol. For a deeper understanding of CTX-1's molecular mechanics, this study employed rigorous 100-ns molecular dynamics simulations, demonstrating CTX-1's remarkable stability in comparison with erlotinib. The Molecular Mechanics Poisson-Boltzmann Surface Area (MM-PBSA) method further corroborated these results, with CTX-1 showing a free binding energy of -105.976 ± 1.916 kJ/mol. The true prowess of CTX-1 was tested against diverse lung cancer cell lines, including A549, Hop-62 and H-1299. CTX-1 not only significantly outperformed erlotinib in anticancer activity but also exhibited a spectrum of therapeutic effects. It effectively diminished cancer cell viability, induced DNA damage, halted cell cycle progression, generated reactive oxygen species (ROS), impaired mitochondrial transmembrane potential, instigated apoptosis and successfully inhibited EGFR-TKD. This study not only underscores the potential of CTX-1 a formidable contender in lung cancer treatment but also marks a paradigm shift in oncological therapeutics, offering new horizons in the fight against this formidable disease.


Assuntos
Receptores ErbB , Neoplasias Pulmonares , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Humanos , Receptores ErbB/metabolismo , Receptores ErbB/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Melanoma/patologia , Ligação Proteica , Cloridrato de Erlotinib/farmacologia , Cloridrato de Erlotinib/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Proliferação de Células/efeitos dos fármacos
5.
J Cell Mol Med ; 28(7): e18150, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38494866

RESUMO

The anti-apoptotic proteins, Bcl-2 and Survivin, are consistently overexpressed in numerous human malignancies, notably in colorectal cancer. 2,4-Di-tert-butylphenol (2,4-DTBP) is a naturally occurring phenolic compound known for its diverse biological activities, including anti-cancer properties. The mechanism behind 2,4-DTBP-induced inhibition of cell proliferation and apoptosis in human colorectal cancer cells, specifically regarding Bcl-2 and Survivin, remains to be elucidated. In this study, we employed both in silico and in vitro methodologies to underpin this interaction at the molecular level. Molecular docking demonstrated a substantial binding affinity of 2,4-DTBP towards Bcl-2 (ΔG = -9.8 kcal/mol) and Survivin (ΔG = -5.6 kcal/mol), suggesting a potential inhibitory effect. Further, molecular dynamic simulations complemented by MM-GBSA calculations confirmed the significant binding of 2,4-DTBP with Bcl-2 (dGbind = -54.85 ± 6.79 kcal/mol) and Survivin (dGbind = -32.36 ± 1.29 kcal/mol). In vitro assays using HCT116 colorectal cancer cells revealed that 2,4-DTBP inhibited proliferation and promoted apoptosis in both a dose- and time-dependent manner. Fluorescence imaging and scanning electron microscopy illustrated the classical features associated with apoptosis upon 2,4-DTBP exposure. Cell cycle analysis through flow cytometry highlighted a G1 phase arrest and apoptosis assay demonstrated increased apoptotic cell population. Notably, western blotting results indicated a decreased expression of Bcl-2 and Survivin post-treatment. Considering the cytoprotective roles of Bcl-2 and Survivin through the inhibition of mitochondrial dysfunction, our findings of disrupted mitochondrial bioenergetics, characterized by reduced ATP production and oxygen consumption, further accentuate the functional impairment of these proteins. Overall, the integration of in silico and in vitro data suggests that 2,4-DTBP holds promise as a therapeutic agent targeting Bcl-2 and Survivin in colorectal cancer.


Assuntos
Neoplasias Colorretais , Fenóis , Humanos , Survivina , Simulação de Acoplamento Molecular , Proliferação de Células
6.
J Cell Biochem ; 125(4): e30538, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38369774

RESUMO

This computational study investigates 21 bioactive compounds from the Asteraceae family as potential inhibitors targeting the Spike protein (S protein) of SARS-CoV-2. Employing in silico methods and simulations, particularly CDOCKER and MM-GBSA, the study identifies two standout compounds, pterodontic acid and cichoric acid, demonstrating robust binding affinities (-46.1973 and -39.4265 kcal/mol) against the S protein. Comparative analysis with Favipiravir underscores their potential as promising inhibitors. Remarkably, these bioactives exhibit favorable ADMET properties, suggesting safety and efficacy. Molecular dynamics simulations validate their stability and interactions, signifying their potential as effective SARS-CoV-2 inhibitors.


Assuntos
Asteraceae , Simulação de Dinâmica Molecular , SARS-CoV-2 , Antivirais/farmacologia , Simulação de Acoplamento Molecular
7.
Clin Immunol ; 264: 110261, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38788884

RESUMO

Gene regulatory elements, such as enhancers, greatly influence cell identity by tuning the transcriptional activity of specific cell types. Dynamics of enhancer landscape during early human Th17 cell differentiation remains incompletely understood. Leveraging ATAC-seq-based profiling of chromatin accessibility and comprehensive analysis of key histone marks, we identified a repertoire of enhancers that potentially exert control over the fate specification of Th17 cells. We found 23 SNPs associated with autoimmune diseases within Th17-enhancers that precisely overlapped with the binding sites of transcription factors actively engaged in T-cell functions. Among the Th17-specific enhancers, we identified an enhancer in the intron of RORA and demonstrated that this enhancer positively regulates RORA transcription. Moreover, CRISPR-Cas9-mediated deletion of a transcription factor binding site-rich region within the identified RORA enhancer confirmed its role in regulating RORA transcription. These findings provide insights into the potential mechanism by which the RORA enhancer orchestrates Th17 differentiation.


Assuntos
Diferenciação Celular , Elementos Facilitadores Genéticos , Células Th17 , Humanos , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Elementos Facilitadores Genéticos/genética , Células Th17/imunologia , Polimorfismo de Nucleotídeo Único , Regulação da Expressão Gênica , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Sítios de Ligação/genética , Sistemas CRISPR-Cas
8.
Biochem Biophys Res Commun ; 705: 149756, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38460440

RESUMO

Exacerbated expression of TLR4 protein (foremost pattern recognition receptor) during obesity could trigger NF-κB/iNOS signaling through linker protein (MyD88), predisposed to an indispensable inflammatory response. The induction of this detrimental cascade leads to myocardial and vascular abnormalities. Molecular docking was studied for protein-ligand interaction between these potential targets and resveratrol. The pre-treatment of resveratrol (20 mg/kg/p.o/per day for ten weeks) was given to investigate the therapeutic effect against HFD-induced obesity and associated vascular endothelial dysfunction (VED) and myocardial infarction (MI) in Wistar rats. In addition to accessing the levels of serum biomarkers for VED and MI, oxidative stress, inflammatory cytokines, and histopathology of these tissues were investigated. Lipopolysaccharide (for receptor activation) and protein expression analysis were introduced to explore the mechanistic involvement of TLR4/MyD88/NF-κB/iNOS signaling. Assessment of in-silico analysis showed significant interaction between protein and ligand. The involvement of this proposed signaling (TLR4/MyD88/NF-κB/iNOS) was further endorsed by the impact of lipopolysaccharide and protein expression analysis in obese and treated rats. Moreover, resveratrol pre-treated rats showed significantly lowered cardio and vascular damage measured by the distinct down expression of the TLR4/MyD88/NF-κB/iNOS pathway by resveratrol treatment endorses its ameliorative effect against VED and MI.


Assuntos
Infarto do Miocárdio , Estilbenos , Ratos , Animais , NF-kappa B/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor 4 Toll-Like/metabolismo , Resveratrol/farmacologia , Estilbenos/farmacologia , Estilbenos/uso terapêutico , Lipopolissacarídeos/farmacologia , Ligantes , Simulação de Acoplamento Molecular , Ratos Wistar , Infarto do Miocárdio/tratamento farmacológico , Dieta
9.
Small ; : e2403056, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38726792

RESUMO

Energy conversion and transfer of enzyme-catalyzed reactions at molecular level are an interesting and challenging scientific topic that helps understanding biological processes in nature. In this study, it is demonstrated that enzyme-catalyzed reactions can enhance diffusion of surrounding molecules and thus accelerate cargo transport within 1D micro/nanochannels. Specifically, urease is immobilized on the inner walls of silica micro/nano-tubes to construct bio-catalytically active micro/nanochannels. The catalytic reaction inside the channels drives a variety of cargoes, including small dye molecules, polymers, and rigid nanoparticles (e.g., quantum dots, QDs), to pass through these micro/nanochannels much faster than they will by free diffusion. The enhanced diffusion of molecular species inside the channels is validated by direct observation of the Brownian motion of tracer particles, and further confirmed by significantly enhanced Raman intensity of reporter molecules. Finite element and Brownian dynamics simulations provide a theoretical understanding of these experimental observations. Furthermore, the effect of the channels' size on the diffusion enhancement is examined. The acceleration effect of the cargo transport through these enzymatically active micro/nanochannels can be turned on or off via chemical activators or inhibitors. This study provides valuable insights on the design of biomimetic channels capable of controlled and efficient transmembrane transport.

10.
Chemistry ; : e202400885, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39032088

RESUMO

Carbon dots (CDs) are novel carbon-based luminescent materials with wide-ranging applications in biosensing, bioimaging, drug transportation, optical devices, and beyond. Their advantageous attributes, including biocompatibility, biodegradability, antioxidant activity, photostability, small particle size (< 10 nm), and strong light absorption and excitation across a broad range of wavelengths, making them promising candidates in the field of photodynamic therapy (PDT) as photosensitizers (PSs). Further enhancements in functionality are imperative to enhance the effectiveness of CDs in PDT applications, notwithstanding their inherent benefits. Recently, doping agents and solvents have been demonstrated to improve CDs' optical properties, solubility, cytotoxicity, and organelle targeting efficiency. These improvements result from modifications to the CDs' carbon skeleton matrices, functional groups on the surface state, and chemical structures. This review discusses the modification of CDs with heteroatom dopants, dye dopants, and solvents to improve their physicochemical and optical properties for PDT applications. The correlations between the surface chemistry, functional groups, structure of the CDs and their optical characteristics toward quantum yield, redshift feature and reactive oxygen species generation, have also been discussed. Finally, the progressive trends for the use of CDs in PDT applications are also addressed in this review.

11.
Langmuir ; 40(21): 10884-10894, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38756056

RESUMO

Colloids that generate chemicals, or "chemically active colloids", can interact with their neighbors and generate patterns via forces arising from such chemical gradients. Examples of such assemblies of chemically active colloids are abundant in the literature, but a unified theoretical framework is needed to rationalize the scattered results. Combining experiments, theory, Brownian dynamics, and finite element simulations, we present here a conceptual framework for understanding how immotile, yet chemically active, colloids assemble. This framework is based on the principle of ionic diffusiophoresis and diffusioosmosis and predicts that a chemically active colloid interacts with its neighbors through short- and long-range interactions that can be either repulsive or attractive, depending on the relative diffusivity of the released cations and anions, and the relative zeta potential of a colloidal particle and the planar surface on which it resides. As a result, 4 types of pairwise interactions arise, leading to 4 different types of colloidal assemblies with distinct patterns. Using short-range attraction and long-range attraction (SALR) systems as an example, we show quantitative agreement between the framework and experiments. The framework is then applied to rationalize a wide range of patterns assembled from chemically active colloids in the literature exhibiting other types of pairwise interactions. In addition, the framework can predict what the assembly looks like with minimal experimental information and help infer ionic diffusivity and zeta potential values in systems where these values are inaccessible. Our results represent a solid step toward building a complete theory for understanding and controlling chemically active colloids, from the molecular level to their mesoscopic superstructures and ultimately to the macroscopic properties of the assembled materials.

12.
Clin Transplant ; 38(1): e15193, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37964657

RESUMO

BACKGROUND: Pediatric hematological cancer survivors who undergo hematopoietic stem cell transplantation (HSCT) may experience long-term neurocognitive impairments. This systematic review aims to assess the neurocognitive outcomes in pediatric hematological cancer survivors at least 5 years post-HSCT. METHODOLOGY: A comprehensive search was conducted in multiple databases, including PubMed, ScienceDirect, Cochrane Library, and ClinicalTrials.gov, until October 2022. Relevant studies assessing the neurocognitive affect after 5 years of HSCT were identified and included in the review. The quality of included studies was assessed using the ROBINS-I tool to evaluate the risk of bias. RESULTS: A total of five studies met the inclusion criteria and were included in the review. The studies consistently demonstrated adverse effects of HSCT on neurocognitive outcomes in pediatric hematological cancer survivors after 5 years of the treatment. The most prominent impact was observed on global cognitive outcomes, including intelligence, attention, memory, and executive functioning. Specific cognitive domains, such as processing speed and academic achievement, were also significantly affected. Several studies reported a relationship between HSCT-related factors (e.g., age at transplantation, radiation therapy, graft-versus-host disease) and neurocognitive impairments. CONCLUSION: This systematic review provides evidence of the adverse impact of HSCT on neurocognitive outcomes in pediatric hematological cancer survivors at least 5 years post-transplantation. The findings highlight the importance of long-term monitoring and intervention strategies to mitigate these neurocognitive sequelae. Future research should focus on identifying risk factors and developing targeted interventions to optimize the neurocognitive functioning of this vulnerable population. Healthcare professionals involved in the care of pediatric hematological cancer survivors should be aware of these potential long-term neurocognitive effects and incorporate appropriate assessments and interventions into survivorship care plans.


Assuntos
Doença Enxerto-Hospedeiro , Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Humanos , Criança , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/complicações , Sobreviventes , Doença Enxerto-Hospedeiro/etiologia
13.
Nanotechnology ; 35(16)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38150724

RESUMO

The coherent perfect absorption (CPA) occurring in the graphene sheet suspended in air can be utilized to develop an ultrathin, ultra-broadband absorber working in the frequency range from a few hertz (Hz) to terahertz (THz) with perfect absorption. A graphene sheet is studied to induce the CPA to cover radio, microwave and lower THz frequency ranges. A graphene resonator able to provide the surface plasmon resonance (SPR) is combined with the graphene sheet to provide CPA at either side of a thin dielectric layer forms metamaterial structure with the cavity and enhances the absorption bandwidth in the THz region by creating a resonance near quasi-CPA frequency. A dielectric silicon resonator is embedded in the structure, which creates dipolar resonances between the resonances obtained by the formed cavity between the graphene sheet and resonator. This enhances the absorption level in the THz region. The absorption bandwidth is further enhanced to 7 THz by including a graphene disc at the top of the silicon resonator. Thus, the multiple multi-order resonances occurring in the silicon dielectric and SPR of graphene resonators are merged with the phenomena of CPA occurring in the graphene sheets to extend the CPA bandwidth in the THz regime. The doping level of graphene or its tunable Fermi energy based on the applied DC electric field provides the tunability in the total obtained absorption bandwidth. The symmetric structure provides polarization-insensitive behavior with an allowed incident angle of more than 45° with more than 90% absorption.

14.
Immunol Invest ; 53(4): 695-711, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38504489

RESUMO

Mast cells play important role in acquired and natural immunity making these favorable therapeutic targets in various inflammatory diseases. Here we observed that, pentacyclic tri terpenoid betulinic acid (BA) treatment resulted in a significantly high number (9%) of cells positive for Hoechst and negative for annexin-V indicating that BA could interfere with plasma membrane integrity. The degranulation of both activated and non-activated mast cells was enhanced upon treatment with BA. The pre-treatment of BA had remarkable effect on calcium response in activated mast cells which showed increased calcium influx relative compared to untreated cells. The results also showed potentially less migration of BA treated mast cells signifying the possible effect of BA on cell membrane. BA treatment resulted in a significant increase in mRNA levels of IL-13 while as mRNA levels of other target cytokines, IL-6 and TNF-α seem to be not affected. Moreover, there was global Increase in phosphorylation of signaling proteins and no significant change in phosphorylation of FcεRI receptors indicating that the effect of BA was independent of signaling cascade or FcεRI receptor mediated mast cell aggregation. Overall, these results portray BA potentiates mast cell effector functions by compromising the membrane integrity and independent of FcεRI involvement.


Assuntos
Ácido Betulínico , Degranulação Celular , Membrana Celular , Mastócitos , Triterpenos Pentacíclicos , Receptores de IgE , Triterpenos , Mastócitos/efeitos dos fármacos , Mastócitos/imunologia , Mastócitos/metabolismo , Triterpenos Pentacíclicos/farmacologia , Degranulação Celular/efeitos dos fármacos , Receptores de IgE/metabolismo , Membrana Celular/metabolismo , Membrana Celular/efeitos dos fármacos , Triterpenos/farmacologia , Animais , Transdução de Sinais/efeitos dos fármacos , Cálcio/metabolismo , Ratos , Fosforilação/efeitos dos fármacos , Citocinas/metabolismo
15.
J Fluoresc ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38913089

RESUMO

Free radicals, products of oxidative processes, induce cellular damage linked to diseases like Parkinson's and diabetes due to increased reactive oxygen species (ROS) levels. Catalase, crucial for scavenging ROS, emerges as a therapeutic agent against ailments including atherosclerosis and tumor progression. Its primary function involves breaking down hydrogen peroxide into water and oxygen. Research on catalase-drug interactions reveals structural changes under specific conditions, affecting its activity and cellular antioxidant balance, highlighting its pivotal role in defending against oxidative stress-related diseases. Hence, targeting catalase is considered an effective strategy for controlling ROS-induced cellular damage. This study investigates the interaction between bovine liver catalase and glipizide using spectroscopic and computational methods. It also explores glipizide's effect on catalase activity. More than 20% inhibition of catalase enzymatic activity was recorded in the presence of 50 µM glipizide. To investigate the inhibition of catalase activity by glipizide, we performed a series of binding studies. Glipizide was found to form a complex with catalase with moderate affinity and binding constant in the range of 3.822 to 5.063 × 104 M-1. The binding was spontaneous and entropically favourable. The α-helical content of catalase increased from 24.04 to 29.53% upon glipizide complexation. Glipizide binding does not alter the local environment surrounding the tyrosine residues while a notable decrease in polarity around the tryptophan residues of catalase was recorded. Glipizide interacted with numerous active site residues of catalase including His361, Tyr357, Ala332, Asn147, Arg71, and Thr360. Molecular simulations revealed that the catalase-glipizide complex remained relatively stable in an aqueous environment. The binding of glipizide had a negligible effect on the secondary structure of catalase, and hydrogen bonds persisted consistently throughout the trajectory. These results could aid in the development of glipizide as a potent catalase inhibitor, potentially reducing the impact of reactive oxygen species (ROS) in the human body.

16.
Phys Chem Chem Phys ; 26(2): 1385-1395, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38112010

RESUMO

Engineering structures like nanocages, shells, and containers, by self-assembly of colloids is a challenging problem. One of the main challenges is to define the shape of the individual subunits to control the radius of the closed shell structures. In this work, we have proposed a simple model for the subunit, which comprises a spheroidal or spherical hardcore decorated with an annular patch. The self-assembly of these building blocks leads to the formation of monodispersed spherical cages (close shells) or containers (curved clusters). For a spheroid with a given bonding range, the curvature of the shell is analytically related to only the patch angle of the building blocks and independent of the shape of the subunits. This model with only one control parameter can be used to engineer cages with the desired radius, which also have been verified using thermodynamic calculations. In the phase diagram of the system, 4 phases are identified which includes gas, closed shell, partially closed (containers) shell and percolated structures. When the diameters of the spherical cages formed are small, we observe an icosahedral symmetry similar to virus capsids. We also observed that the kinetics of the cage formation is very similar to the nucleation and growth kinetics of viruses and is the key factor in determining the yield of closed shells.

17.
Curr Osteoporos Rep ; 22(3): 301-307, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38625510

RESUMO

PURPOSE OF REVIEW: This review summarizes evidence on osteocyte support of extramedullary and bone marrow adipocyte development and discusses the role of endogenous osteocyte activities of nuclear receptors peroxisome proliferator-activated receptor gamma (PPARG) and alpha (PPARA) in this support. RECENT FINDINGS: PPARG and PPARA proteins, key regulators of glucose and fatty acid metabolism, are highly expressed in osteocytes. They play significant roles in the regulation of osteocyte secretome and osteocyte bioenergetics; both activities contributing to the levels of systemic energy metabolism in part through an effect on metabolic function of extramedullary and bone marrow adipocytes. The PPARs-controlled osteocyte endocrine/paracrine activities, including sclerostin expression, directly regulate adipocyte function, while the PPARs-controlled osteocyte fuel utilization and oxidative phosphorylation contribute to the skeletal demands for glucose and fatty acids, whose availability is under the control of adipocytes. Bone is an inherent element of systemic energy metabolism with PPAR nuclear receptors regulating osteocyte-adipocyte metabolic axes.


Assuntos
Adipócitos , Tecido Adiposo , Medula Óssea , Metabolismo Energético , Osteócitos , PPAR gama , Osteócitos/metabolismo , Osteócitos/fisiologia , Humanos , PPAR gama/metabolismo , Medula Óssea/metabolismo , Tecido Adiposo/metabolismo , Adipócitos/metabolismo , Metabolismo Energético/fisiologia , PPAR alfa/metabolismo , Animais
18.
BMC Public Health ; 24(1): 1870, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39003451

RESUMO

Despite domestic violence and related homicides perpetrated by partners and/or in-laws being a significant public health problem in India, there are no reliable and valid instruments to identify and intervene with women in domestic violence relationships. Continued domestic violence can escalate to severe, near-lethal, or lethal violence or homicide. The Danger Assessment (DA) is a risk assessment instrument designed to assess the likelihood of severe, near-lethal, or lethal violence in abusive relationships. However, the DA is not designed to determine the risk of future severe, near-lethal, or lethal violence by in-laws. In-law abuse plays a significant role in domestic violence-related homicides in India and other countries with similar cultural norms. This study addressed this gap by developing the Danger Assessment for in-laws (DA-L) to assess risk from in-laws, alongside the Danger Assessment for Women in India (DA-WI) to assess risk from partners. The study also examined the psychometric properties of the DA-L and DA-WI. Longitudinal data from 150 women in India were used to measure the reliability and validity of the two versions of the DA. The original DA items and additional risk items were examined using relative risk ratios for their relationship with severe violence at three-month follow-ups. Predictive validity was tested with the receiver operating characteristic curve. The study resulted in reliable and valid measures (11 items DA-L and 26-items DA-WI) of risk. The versions of the DA can be useful for practitioners in India and those working with Indian women in the US and other countries. The DAs can be used for identifying women in domestic violence relationships who are at risk for future severe domestic violence and guide the provision of tailored safety plans.


Assuntos
Violência Doméstica , Homicídio , Humanos , Feminino , Índia/epidemiologia , Medição de Risco , Adulto , Homicídio/estatística & dados numéricos , Homicídio/psicologia , Violência Doméstica/estatística & dados numéricos , Violência Doméstica/psicologia , Adulto Jovem , Psicometria , Pessoa de Meia-Idade , Violência por Parceiro Íntimo/estatística & dados numéricos , Violência por Parceiro Íntimo/psicologia , Adolescente , Reprodutibilidade dos Testes , Masculino , Maus-Tratos Conjugais/estatística & dados numéricos , Maus-Tratos Conjugais/psicologia , Inquéritos e Questionários
19.
Artigo em Inglês | MEDLINE | ID: mdl-39014968

RESUMO

AIM: This retrospective study aims to analyse the epidemiology, clinical and neuroimaging features, treatment modalities, and outcomes of paediatric idiopathic intracranial hypertension (IIH) in a tertiary care centre in Australia. METHODS: Using the International Classification of Diseases Diagnostic Criteria for IIH, we identified and analysed a cohort of children diagnosed with IIH over a 5-year period (2017-2022). Data on patient demographics, symptomatology, examination findings, investigative results, treatments and outcomes were collected from medical records and electronic health records. RESULTS: A total of 45 cases were analysed. The pre-pubertal group saw a male predominance and the post-pubertal a female one. Increased body mass index was an associated comorbidity in majority of patients. Headaches (89%) and visual symptoms (56%) were the most common symptoms, with tinnitus also seen in 20% of patients. Papilledema was detected in 91% of the cases examined. The commonest neuroimaging features were optic nerve sheath distention (78%) and empty sella (49%). Acetazolamide was the primary treatment, with most patients responding well. Only a minority required surgical intervention. Long-term resolution of headaches was achieved in 89% of patients. CONCLUSIONS: The incidence of paediatric IIH in the West Australian population appears relatively high. It presents with subtle symptoms, emphasising the need for increased awareness among health-care providers. Younger children may represent a distinct subgroup with unique clinical features. Timely diagnosis and aggressive medical management lead to favourable outcomes. However, weight loss interventions showed limited effectiveness. This study underscores the importance of early recognition and management of paediatric IIH to optimise patient outcomes.

20.
Mikrochim Acta ; 191(6): 357, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814503

RESUMO

Super hydrophobic porous silicon surface is prepared using a wet chemical synthesis route. Scanning electron microscopic investigation confirms a correlation between pore size and reaction time. SERS substrates are prepared by silver nanoparticle deposition on porous silicon surface. They exhibit excellent characteristics in terms of sensitivity, reproducibility, stability, and uniformity. They could detect rhodamine 6G in femtomolar range with SERS enhancement factor of ~ 6.1 × 1012, which is best ever reported for these substrates. Molecule-specific sensing of water pollutants such as methylene blue, glyphosate, and chlorpyrifos, is demonstrated for concentrations well below their permissible limits along with excellent enhancement factors. Porous silicon substrate functionalized with Ag nanoparticles demonstrates to be a promising candidate for low-cost, long-life, reliable sensors for environmental conservation applications.

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