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1.
J Int Med Res ; 51(10): 3000605231208594, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37903317

RESUMO

Colon cancer in patients with situs inversus totalis is rarely associated with dextrocardia, and chemotherapy is commonly used for treatment. Central venous access devices are used to administer intravenous fluids and chemotherapy in patients with colon cancer. Compared with peripherally inserted central catheters and Hickman-type tunneled catheters, totally implantable vascular access devices (TIVADs) are safer and more effective. However, positioning the catheter tip may be challenging in patients with dextrocardia and situs inversus. We herein describe a novel case involving a patient with dextrocardia and colon cancer who was treated by TIVAD insertion with intracavitary electrocardiography-aided tip localization.


Assuntos
Cateteres Venosos Centrais , Neoplasias do Colo , Dextrocardia , Situs Inversus , Humanos , Cateteres de Demora/efeitos adversos , Dextrocardia/complicações , Dextrocardia/diagnóstico por imagem , Situs Inversus/complicações , Neoplasias do Colo/complicações , Neoplasias do Colo/tratamento farmacológico
2.
Eur J Pharmacol ; 954: 175867, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37369297

RESUMO

The eukaryotic translation initiation factor 4 (EIF4) family is a major contributor to the recruitment of mRNAs to ribosomes during the initial translation stage in eukaryotes, whose dysregulation either allows for cancer transformation or prevents disordered cancerous cell growth. Circular RNAs (circRNAs), which exhibit distinctive structures and are widely expressed in eukaryotes, are anticipated to be clinical diagnostic biomarkers for cancer therapy. There is considerable evidence that EIF4s can influence the biogenesis, transport, and function of circRNAs and, in turn, circRNAs can control the expressions of EIF4s through certain molecular pathways. Herein, we primarily review the emerging studies of the EIF4 family and pinpoint the roles of dysregulated EIF4s in cancer. We also evaluate the patterns of intricate interactions between circRNAs and EIF4s and discuss the potential utility of circRNA-based therapeutics targeting EIF4s in clinical cancer research.


Assuntos
Neoplasias , RNA Circular , Humanos , RNA Circular/genética , RNA/metabolismo , RNA Mensageiro , Neoplasias/genética , Neoplasias/terapia , Fatores de Iniciação de Peptídeos , Biomarcadores
3.
Front Immunol ; 13: 807840, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812443

RESUMO

Prostate cancer, recognized as a "cold" tumor, has an immunosuppressive microenvironment in which regulatory T cells (Tregs) usually play a major role. Therefore, identifying a prognostic signature of Tregs has promising benefits of improving survival of prostate cancer patients. However, the traditional methods of Treg quantification usually suffer from bias and variability. Transcriptional characteristics have recently been found to have a predictive power for the infiltration of Tregs. Thus, a novel machine learning-based computational framework has been presented using Tregs and 19 other immune cell types using 42 purified immune cell datasets from GEO to identify Treg-specific mRNAs, and a prognostic signature of Tregs (named "TILTregSig") consisting of five mRNAs (SOCS2, EGR1, RRM2, TPP1, and C11orf54) was developed and validated to monitor the prognosis of prostate cancer using the TCGA and ICGC datasets. The TILTregSig showed a stronger predictive power for tumor immunity compared with tumor mutation burden and glycolytic activity, which have been reported as immune predictors. Further analyses indicate that the TILTregSig might influence tumor immunity mainly by mediating tumor-infiltrating Tregs and could be a powerful predictor for Tregs in prostate cancer. Moreover, the TILTregSig showed a promising potential for predicting cancer immunotherapy (CIT) response in five CIT response datasets and therapeutic resistance in the GSCALite dataset in multiple cancers. Our TILTregSig derived from PBMCs makes it possible to achieve a straightforward, noninvasive, and inexpensive detection assay for prostate cancer compared with the current histopathological examination that requires invasive tissue puncture, which lays the foundation for the future development of a panel of different molecules in peripheral blood comprising a biomarker of prostate cancer.


Assuntos
Neoplasias da Próstata , Linfócitos T Reguladores , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Fatores Imunológicos/metabolismo , Imunoterapia/métodos , Masculino , Prognóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/terapia , Microambiente Tumoral
4.
Chem Sci ; 12(35): 11620-11646, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34659698

RESUMO

Abnormal expression of proteins, including catalytic and expression dysfunction, is directly related to the development of various diseases in living organisms. Reactive oxygen species (ROS) could regulate protein expression by redox modification or cellular signal pathway and thus influence the development of disease. Determining the expression level and activity of these ROS-associated proteins is of considerable importance in early-stage disease diagnosis and the identification of new drug targets. Fluorescence imaging technology has emerged as a powerful tool for specific in situ imaging of target proteins by virtue of its non-invasiveness, high sensitivity and good spatiotemporal resolution. In this review, we summarize advances made in the past decade for the design of fluorescent probes that have contributed to tracking ROS-associated proteins in disease. We envision that this review will attract significant attention from a wide range of researchers in their utilization of fluorescent probes for in situ investigation of pathological processes synergistically regulated by both ROS and proteins.

5.
Chem Commun (Camb) ; 57(47): 5838-5841, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34008637

RESUMO

We synthesized an ultrasensitive probe TP-Golgi for the two-photon ratiometric fluorescence imaging of Golgi polarity. Probe TP-Golgi possesses a large Stokes shift, excellent sensitivity and good selectivity to quantitatively detect environmental polarity. By application of TP-Golgi, we found that the Golgi polarity increased obviously in the kidneys of mice with AKI.


Assuntos
Injúria Renal Aguda/diagnóstico por imagem , Polaridade Celular/efeitos dos fármacos , Corantes Fluorescentes/química , Complexo de Golgi/efeitos dos fármacos , Imagem Óptica , Fótons , Injúria Renal Aguda/induzido quimicamente , Linhagem Celular , Corantes Fluorescentes/síntese química , Complexo de Golgi/patologia , Humanos , Estrutura Molecular
6.
ACS Chem Neurosci ; 8(7): 1577-1588, 2017 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-28406293

RESUMO

Amyloid-ß (Aß40/Aß42) peptide with a length of 40 or 42 residues is naturally secreted as cleavage product of the amyloid precursor protein, and formation of Aß aggregates in a patient's brain is a hallmark of Alzheimer's disease (AD). Therefore, disaggregation and disruption provide potential therapeutic approaches to reduce, inhibit, and even reverse Aß aggregation. The disaggregation/inhibition effect of the inhibitors applies generally to both Aß40 and Aß42 aggregations. Here we capture the atomic-level details of the interaction between Aß40/Aß42 and either natural tanshinone compound TS1 or its derivative TS0, and observe novel results by using molecular dynamics simulations. We observe that the natural TS1 indeed inhibits the monomolecular Aß42 (mAß42) aggregation and disaggregates Aß42 amyloid fibrils, being in good agreement with the experimental results. TS1 is favorable to stabilize mAß40 and even Aß40 fibril, playing an opposite role to that in the Aß42 counterpart, however. TS0 can inhibit the misfolding of either mAß40 or mAß42 and disaggregate Aß42 fibril but stabilize the Aß40 fibril. Using a combination of secondary structural analysis, MM-PBSA binding energy calculations, and radial distribution functions computations, we find that both TS0 and TS1, especially the former, prefer to bind at the charged residues within disordered N-terminus with a scarce positive binding energy and disappear the characteristic C-terminal bend region of Aß42 fibril, as well as twist the Aß42 fibril seriously. It turns out to destabilize the Aß42 fibril and enable the conversion of U-shaped Aß42 fibril from the onefold to the twofold morphologies. The N-terminal binding preference helps us to identify N-terminal region as the specific epitope for specific inhibitors/drugs (such as TS0 and analogues), heralding unusual inhibition/disaggregation or stabilization mechanisms, and offering an alternative direction in engineering new inhibitors to treat AD.


Assuntos
Abietanos/farmacologia , Peptídeos beta-Amiloides/antagonistas & inibidores , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/antagonistas & inibidores , Agregação Patológica de Proteínas/tratamento farmacológico , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Sítios de Ligação , Ligação de Hidrogênio , Simulação de Dinâmica Molecular , Fragmentos de Peptídeos/metabolismo , Agregação Patológica de Proteínas/metabolismo , Domínios Proteicos , Dobramento de Proteína/efeitos dos fármacos , Multimerização Proteica/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos
7.
Chemphyschem ; 17(16): 2558-66, 2016 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-27146076

RESUMO

In this study, structural and mechanical properties of a series of models of Aß42 (one- and two-fold) and Aß40 (two- and three-fold) fibrils have been computed by using all-atom molecular dynamics simulations. Based on calculations of the twist angle (θ) and periodicity (v=360d/θ), oligomers formed by 20, 11, and 13 monomers were found to be the smallest realistic models of three-fold Aß40 , one-fold Aß42 , and two-fold Aß42 fibrils, respectively. Our results predict that the Aß40 fibrils initially exist in two staggered conformations [STAG(+2) and STAG(+1)] and then undergo a [STAG(+2)→STAG(+1)] transformation in a size-dependent manner. The length of the loop region consisting of the residues 23-29 shrinks with the elongation of both Aß40 and Aß42 fibrils. A comparison of the computed potential energy suggests that a two-fold Aß40 aggregate is more stable than its three-fold counterpart, and that Aß42 oligomers can exist only in one-fold conformation for aggregates of more than 11 monomers in length. The computed Young's modulus and yield strengths of 50 GPa and 0.95 GPa, respectively, show that these aggregates possess excellent material properties.


Assuntos
Peptídeos beta-Amiloides/química , Fragmentos de Peptídeos/química , Modelos Moleculares , Simulação de Dinâmica Molecular , Conformação Proteica
8.
ACS Chem Neurosci ; 7(5): 599-614, 2016 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-26871000

RESUMO

The aggregation of amyloid-ß (Aß) peptide induced by Cu(2+) is a key factor in development of Alzheimer's disease (AD), and metal ion chelation therapy enables treatment of AD. Three CQi (i = 1, 2, and 3 with R = H, Cl, and NO2, respectively) drugs had been verified experimentally to be much stronger inhibitors than the pioneer clioquinol (CQ) in both disaggregation of Aß40 aggregate and reduction of toxicity induced by Cu(2+) binding at low pH. Due to the multiple morphologies of Cu(2+)-Aß40 complexes produced at different pH states, we performed a series of molecular dynamics simulations to explain the structural changes and morphology characteristics as well as intrinsic disaggregation mechanisms of three Cu(2+)-Aß40 models in the presence of any of the three CQi drugs at both low and high pH states. Three inhibition mechanisms for CQi were proposed as "insertion", "semi-insertion", and "surface" mechanisms, based on the morphologies of CQi-model x (CQi-x, x = 1, 2, and 3) and the strengths of binding between CQi and the corresponding model x. The insertion mechanism was characterized by the morphology with binding strength of more than 100 kJ/mol and by CQi being inserted or embedded into the hydrophobic cavity of model x. In those CQi-x morphologies with lower binding strength, CQi only attaches on the surface or inserts partly into Aß peptide. Given the evidence that the binding strength is correlated positively with the effectiveness of drug to inhibit Aß aggregation and thus to reduce toxicity, the data of binding strength presented here can provide a reference for one to screen drugs. From the point of view of binding strength, CQ2 is the best drug. Because of the special role of Asp23 in both Aß aggregation and stabilizing the Aß fibril, the generation of a H-bond between CQ3 and Asp23 of the Aß40 peptide is believed to be responsible for CQ3 having the strongest disaggregation capacity. Therefore, besides strong binding, stronger propensity to H-bond with Asp23 would be another key factor to be taken seriously into account in drug screens. Meanwhile, the structural characteristics of drug CQi itself are also worthy of attention. First, the increasing polarity from CQ1 and CQ2 to CQ3 in turn results in increasing probability and strength of the interaction between the drug and the N-terminal (NT) region of Aß40, which obviously inhibits Aß peptide aggregation induced by Cu(2+) binding. Second, both the benzothiazole ring and phenol ring of CQi can overcome the activation energy barrier (∼16 kJ/mol) to rotate flexibly around the intramolecular C7-N14 bond to achieve the maximum match and interaction with the ambient Aß40 residues. Such a structural feature of CQi paves the new way for ones in selection and modification of a drug.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides/metabolismo , Quelantes/metabolismo , Cobre/metabolismo , Simulação de Dinâmica Molecular , Fragmentos de Peptídeos/metabolismo , Agregados Proteicos/fisiologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/toxicidade , Quelantes/química , Quelantes/uso terapêutico , Cobre/toxicidade , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/toxicidade , Ligação Proteica/fisiologia , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína
9.
Int J Nanomedicine ; 7: 3295-307, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22848161

RESUMO

Malignant gliomas are primary brain tumors with high rates of morbidity and mortality; they are the fourth most common cause of cancer death. Novel diagnostic and therapeutic techniques based on nanomaterials provide promising options in the treatment of malignant gliomas. In order to evaluate the potential of FePt nanoparticles (NPs) for malignant glioma therapy, FePt NPs with different surface coatings and components were tunably synthesized using oleic acid/oleylamine (OA/OA) and cysteines (Cys) as the capping agents, respectively. The samples were characterized using X-ray diffraction, transmission electron microscopy (TEM), X-ray photon spectroscopy, Fourier transform infrared spectroscopy, atomic absorption spectrum, and zeta potential. The influence of the surface coatings and components of the FePt NPs on the proliferation of glioma cells was assessed through MTT assay and TEM observation using three typical glioma cell lines (glioma U251 cells, astrocytoma U87 cells, and neuroglioma H4 cells) as in vitro models. The results showed that the proliferation of glioma cells was significantly suppressed by lipophilic FePt-OA/OA NPs in a time- and/or dose-dependent manner, while no or low cytotoxic effects were detected in the case of hydrophilic FePt-Cys NPs. The IC50 value of FePt-OA/OA NPs on the three glioma cell lines was approximately 5-10 µg mL⁻¹ after 24 hours' incubation. Although the cellular uptake of FePt NPs was confirmed regardless of the surface coatings and components of the FePt NPs, the suppression of FePt NPs on glioma cell proliferation was dominantly determined by their surface coatings rather than their components. Therefore, these results demonstrate that, through engineering of the surface coating, FePt NPs can potentially be developed as novel therapeutic agents for malignant gliomas.


Assuntos
Antineoplásicos/farmacologia , Glioma/tratamento farmacológico , Glioma/patologia , Nanopartículas de Magnetita/administração & dosagem , Platina/farmacologia , Aminas/química , Antineoplásicos/química , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisteína/química , Glioma/metabolismo , Humanos , Nanopartículas de Magnetita/química , Ácido Oleico/química , Tamanho da Partícula , Platina/química , Platina/farmacocinética , Espectroscopia de Infravermelho com Transformada de Fourier
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