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1.
ACS Omega ; 9(24): 26651-26672, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38911725

RESUMEN

Employing a synergistic combination of theoretical density functional theory (DFT) and experimental techniques, we conducted a comprehensive analysis elucidating the structural and pharmacological attributes of 5-(adamantan-1-yl)-4-butyl-2,4-dihydro-3H-1,2,4-triazole-3-thione (5A4BT) as a potent COX inhibitor. The X-ray crystallographic data of 5A4BT showed the pivotal role played by weak interactions, notably π-π and C-H-π interactions, alongside hydrogen bonding, in orchestrating the intricate supramolecular architectures within the crystalline lattice. A quantitative analysis of the arrangement of the crystal structure, as well as both inter- and intramolecular interactions, was conducted using Hirshfeld surfaces and 2D fingerprint plots. Additionally, a comprehensive examination of the IR spectra was undertaken, employing both experimental methods and theoretical DFT techniques, to elucidate the vibrational characteristics of the compound. The strength of intermolecular N-H···S hydrogen bonding and charge transfer within the system was assessed through natural bonding orbital analysis. Moreover, Bader's atoms in molecules theory was employed to estimate the strength of intermolecular hydrogen bonds, revealing strong interactions within the 5A4BT dimer. The title compound exhibited binding affinities of -6.4 and -6.5 kcal/mol for COX1 (PDB 3KK6) and COX2 (1CX2) target proteins, respectively. For the first time, predictions regarding ADMET properties, drug-likeness, and toxicity, including favorable bioavailability, along with 100 ns molecular dynamics simulations, binding free energy, and energy decomposition per residue in the binding cavity of the protein from molecular mechanics generalized born surface area approach, collectively indicate the potential of 5A4BT as a nonselective COX inhibitor.

3.
Elife ; 122023 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-37467143

RESUMEN

How different intrinsic sequence variations and regulatory modifications of histones combine in nucleosomes remain unclear. To test the importance of histone variants in the organization of chromatin we investigated how histone variants and histone modifications assemble in the Arabidopsis thaliana genome. We showed that a limited number of chromatin states divide euchromatin and heterochromatin into several subdomains. We found that histone variants are as significant as histone modifications in determining the composition of chromatin states. Particularly strong associations were observed between H2A variants and specific combinations of histone modifications. To study the role of H2A variants in organizing chromatin states we determined the role of the chromatin remodeler DECREASED IN DNA METHYLATION (DDM1) in the organization of chromatin states. We showed that the loss of DDM1 prevented the exchange of the histone variant H2A.Z to H2A.W in constitutive heterochromatin, resulting in significant effects on the definition and distribution of chromatin states in and outside of constitutive heterochromatin. We thus propose that dynamic exchanges of histone variants control the organization of histone modifications into chromatin states, acting as molecular landmarks.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Cromatina/genética , Histonas/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Heterocromatina/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Nucleosomas/genética
4.
BMC Cancer ; 23(1): 480, 2023 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-37237279

RESUMEN

BACKGROUND: The role of ATF2 in colon cancer (CC) is controversial. Recently, we reported that low ATF2 expression is characteristic of highly invasive tumors, suggesting that ATF2 might also be involved in therapy resistance. 5-Fluorouracil (5-FU) is the best-known chemotherapeutic drug for CC, but drug resistance affects its curative effect. To date, the role of ATF2 in the 5-FU response remains elusive. METHODS/RESULTS: For our study, we had available HCT116 cells (wild-type p53) and HT29 colon tumor cells (mutant p53) and their corresponding CRISPR‒Cas9-generated ATF2-KO clones. We observed that loss of ATF2 triggered dose- and time-dependent 5-FU resistance in HCT116 cells by activating the DNA damage response (DDR) pathway with high p-ATRThr1989 and p-Chk1Ser317 levels accompanied by an increase in the DNA damage marker γ-H2AX in vitro and in vivo using the chicken chorioallantoic membrane (CAM) model. Chk1 inhibitor studies causally displayed the link between DDR and drug resistance. There were contradictory findings in HT29 ATF2-KO cells upon 5-FU exposure with low p-Chk1Ser317 levels, strong apoptosis induction, but no effects on DNA damage. In ATF2-silenced HCT116 p53-/- cells, 5-FU did not activate the DDR pathway. Co-immunoprecipitation and proximity ligation assays revealed that upon 5-FU treatment, ATF2 binds to ATR to prevent Chk1 phosphorylation. Indeed, in silico modelling showed reduced ATR-Chk1 binding when ATF2 was docked into the complex. CONCLUSIONS: We demonstrated a novel ATF2 scaffold function involved in the DDR pathway. ATF2-negative cells are highly resistant due to effective ATR/Chk1 DNA damage repair. Mutant p53 seems to overwrite the tumor suppressor function of ATF2.


Asunto(s)
Neoplasias del Colon , Proteína p53 Supresora de Tumor , Humanos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/genética , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/metabolismo , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/genética , Fluorouracilo/farmacología , Daño del ADN , Factor de Transcripción Activador 2/genética
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 280: 121530, 2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-35752037

RESUMEN

The present work encompasses a combined experimental and theoretical investigation of the molecular structure, vibrational wavenumbers, electronic structure at the ground and electronic excited states, molecular electrostatic potential surface of 7-(Trifluoromethyl)-1H-indole-2-carboxylic acid (TICA) and possibility of the title molecule as an aromatase inhibitor using molecular docking and molecular dynamic simulations. A stable conformer has been obtained using potential energy scans by varying appropriate dihedral angles. The obtained minimum energy conformer was further optimized at the 6-311++G (d, p) basis set by applying the most accepted B3LYP functional. A good agreement between experimental and calculated normal modes of vibration has been observed. The hydrogen-bonded interaction between two monomeric units of TICA has been investigated using NBO,QTAIM, and NCI (noncovalent interactions) analysis. Molecular docking of TICA with human placental aromatase (PDB ID: 3S79) reveals the formation of polar hydrogen bonds as well as hydrophobic interactions between the ligand and the protein, right in the binding cavity. TICA satisfies all pharmacokinetic filters (Lipinski rule of five, the Veber rule, Ghose rule, Egan rule, as well as the Muegge rule) and has a high bioavailability score of 0.85. Dynamic stability of the ligand within the binding pocket of the target protein has been confirmed by 100 ns molecular dynamics simulation results. The present study provides an excellent starting point for additional in vivo research, and TICA may eventually serve as a significant therapeutic candidate for the treatment of breast cancer.


Asunto(s)
Inhibidores de la Aromatasa , Simulación de Dinámica Molecular , Ácidos Carboxílicos , Electrónica , Femenino , Humanos , Indoles , Ligandos , Simulación del Acoplamiento Molecular , Estructura Molecular , Placenta , Embarazo , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Termodinámica , Vibración
6.
Lab Chip ; 21(22): 4330-4351, 2021 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-34664599

RESUMEN

Classically, the need for highly sophisticated instruments with important economic costs has been a major limiting factor for clinical pathology laboratories, especially in developing countries. With the aim of making clinical pathology more accessible, a wide variety of free or economical technologies have been developed worldwide in the last few years. 3D printing and Arduino approaches can provide up to 94% economical savings in hardware and instrumentation in comparison to commercial alternatives. The vast selection of point-of-care-tests (POCT) currently available also limits the need for specific instruments or personnel, as they can be used almost anywhere and by anyone. Lastly, there are dozens of free and libre digital tools available in health informatics. This review provides an overview of the state-of-the-art on cost-effective alternatives with applications in routine clinical pathology laboratories. In this context, a variety of technologies including 3D printing and Arduino, lateral flow assays, plasmonic biosensors, and microfluidics, as well as laboratory information systems, are discussed. This review aims to serve as an introduction to different technologies that can make clinical pathology more accessible and, therefore, contribute to achieve universal health coverage.


Asunto(s)
Patología Clínica , Análisis Costo-Beneficio , Laboratorios , Microfluídica , Pruebas en el Punto de Atención
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 146: 129-41, 2015 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-25813170

RESUMEN

Experimentally observed spectral data (FT-TR and FT-Raman) of 3-methylbezothiazole-2-thione (3MBT2T) were compared with the spectral data obtained by DFT/B3LYP method using 6-311++G(d,p) basis set. UV-Vis spectrum of the title compound was recorded and the electronic properties, such as frontier molecular orbitals and band gap energies were calculated by TD-DFT approach. The molecular properties like dipole moment, polarizability, first static hyperpolarizability, molecular electrostatic potential surface (MEPs), and contour map were calculated to get a better comprehension of the properties of the title molecule. Natural bond orbital (NBO) analysis was applied to investigate the stability of the molecule arising from charge delocalization. Global and local reactivity descriptors were also computed to predict reactivity and reactive sites on the molecule.


Asunto(s)
Modelos Químicos , Tionas/química , Estructura Molecular , Espectrofotometría Ultravioleta
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 133: 626-38, 2014 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-24996206

RESUMEN

Quantum chemical calculations of ground state energy, geometrical structure and vibrational wavenumbers of 1-acetylindole were carried out using density functional (DFT/B3LYP) method with 6-311++G(d,p) basis set. The FT-IR and FT-Raman spectra were recorded in the condensed state. The fundamental vibrational wavenumbers were calculated and a good correlation between experimental and scaled calculated wavenumbers has been accomplished. Electric dipole moment, polarizability and first static hyperpolarizability values of 1-acetylindole have been calculated at the same level of theory and basis set. The results show that the 1-acetylindole molecule possesses nonlinear optical (NLO) behavior with non-zero values. Stability of the molecule arising from hyper-conjugative interactions and charge delocalization has been analyzed using natural bond orbital (NBO) analysis. UV-Visible spectrum of the molecule was recorded in the region 200-500nm and the electronic properties like HOMO and LUMO energies and composition were obtained using TD-DFT method. The calculated energies and oscillator strengths are in good correspondence with the experimental data. The thermodynamic properties of the compound under investigation were calculated at different temperatures.


Asunto(s)
Indoles/química , Modelos Moleculares , Conformación Molecular , Teoría Cuántica , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Termodinámica
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 123: 352-62, 2014 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-24412788

RESUMEN

Extensive spectroscopic investigations along with theoretical quantum chemical studies on 3,5-dimethyl-4-methoxybenzoic acid (DMMBA) have been consummated. The fundamental vibrational transitions were addressed by experimental FT-IR (4000-400cm(-1)) and FT-Raman (4000-10cm(-1)) techniques and density functional calculations at B3LYP/6-311++G(d,p) and B3LYP/6-311++G(df,pd) levels of theory. The (1)H, (13)C and DEPT 135 NMR spectra of studied compound were recorded in deuterated dimethylsulfoxide (DMSO-d6), and compared with computed data obtained by using gauge including atomic orbital (GIAO) method. The electronic absorption spectra in methanol and ethanol solution were evaluated in the range of 200-400nm, and TD-DFT method was chosen for computational study. The spectroscopic and theoretical results were compared to the corresponding properties for monomer and dimer structures for the most stable conformer. Stability of the molecule arising from hyperconjugative interactions and charge delocalization has been analyzed using natural bond orbital (NBO) analysis. Moreover, the thermodynamic and nonlinear optical (NLO) properties were evaluated.


Asunto(s)
Éteres de Hidroxibenzoatos/química , Salicilatos/química , Dimerización , Espectroscopía de Resonancia Magnética , Metilación , Modelos Moleculares , Teoría Cuántica , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman
10.
J Med Case Rep ; 4: 185, 2010 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-20565905

RESUMEN

INTRODUCTION: Metastatic tumors are the most common intra-ocular malignancies and choroid is by far the most common site for intra-ocular malignancies. Multiple foci are usually involved, and bilateral involvement is frequently seen. The primary sites for choroidal metastasis in decreasing order and by gender are: breast, lung, unknown primary, gastrointestinal and pancreas, skin melanoma and other rare sources in females, and lung, unknown primary, gastrointestinal and pancreas, prostate, kidney, skin melanoma and other rare sources in males. Available treatment options are external beam radiotherapy and plaque radiotherapy, while new methods like surgical resection, transpupillary thermotherapy and intravitreal chemotherapy offer promises for the future. The use of chemotherapy alone for choroidal metastases is not widely reported. CASE PRESENTATION: We report the case of a 50-year-old Indian man who had a unilateral solitary lesion in his right eye. He was found to have an adenocarcinoma of the lung with choroidal metastasis as the first presenting sign. There were no findings of metastasis involving his contralateral eye. He was administered chemotherapy based on gemcitabine and carboplatin. He had significant progressive subjective and objective improvement since his first chemotherapy. His current best corrected visual acuity is 20/60 after three cycles of chemotherapy. CONCLUSIONS: Chemotherapy alone can be used as an effective mode of treatment in patients who have primary tumors that respond to chemotherapy.

11.
J Cancer Res Ther ; 5(2): 137-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19542674

RESUMEN

Esophageal carcinoma rarely metastasizes to brain. In our center, among 504 cases of esophageal cancer registered for treatment during a 15-year (1990-2005) period, brain metastasis from esophageal carcinoma was detected in only 1 case. An unusual case of esophageal carcinoma that presented with brain metastasis is reported here.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Neoplasias Esofágicas/diagnóstico , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/cirugía , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/cirugía , Resultado Fatal , Humanos , Masculino , Persona de Mediana Edad
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