Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Telemed J E Health ; 23(7): 608-614, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28092493

RESUMO

BACKGROUND: During clinical case diagnoses, especially in low-resourced areas, the use of vocabularies within Unified Medical Language System (UMLS) can strengthen discussions between health professionals and, in certain cases, eliminate the need, enabling faster treatment. INTRODUCTION: This article presents the benefits of using UMLS as a collaborative discussion tool and verifies its impact. MATERIALS AND METHODS: The Sanar system has been improved by UMLS when using text retrieval to extract relevant medical concepts from cases investigated by the user and to provide contextualized searches of related articles. An experiment was conducted, focused on team engagement and discussion of a Zika virus case using Sanar, both with and without UMLS contextualization. RESULTS: The use of the tool was measured, and it was determined that the discussion in the group with UMLS support was more complete based on better information and inclusion of more variables. Clinicians involved responded to a questionnaire evaluating the relevance of functions. DISCUSSION: From the questionnaire showed that most of the group supported UMLS as important in complex diagnostics; the use of knowledge extraction before discussion is relevant to align knowledge of participants with more variables, such as the Zika virus, and to minimize the need for interaction in widely discussed cases. CONCLUSIONS: Based on the results obtained with the questionnaire, the use of UMLS provides acceleration in the diagnostic process that precedes interaction with other health professionals through clinical discussion tools. For future work, a mobile version will support offline navigation for locations with limited Internet access.


Assuntos
Internet , Colaboração Intersetorial , Unified Medical Language System/normas , Vocabulário Controlado , Infecção por Zika virus/classificação , Infecção por Zika virus/diagnóstico , Zika virus/classificação , Humanos
2.
bioRxiv ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38529509

RESUMO

Brain metastasis of HER2+ breast cancer occurs in about 50% of all women with metastatic HER2+ breast cancer and confers poor prognosis for patients. Despite effective HER2-targeted treatments of peripheral HER2+ breast cancer with Trastuzumab +/-HER2 inhibitors, limited brain permeability renders these treatments inefficient for HER2+ breast cancer brain metastasis (BCBM). The scarcity of suitable patient-derived in-vivo models for HER2+ BCBM has compromised the study of molecular mechanisms that promote growth and therapeutic resistance in brain metastasis. We have generated and characterized new HER2+ BCBM cells (BCBM94) isolated from a patient HER2+ brain metastasis. Repeated hematogenic xenografting of BCBM94 consistently generated BCBM in mice. The clinically used receptor tyrosine kinase inhibitor (RTKi) Lapatinib blocked phosphorylation of all ErbB1-4 receptors and induced the intrinsic apoptosis pathway in BCBM94. Neuregulin-1 (NRG1), a ligand for ErbB3 and ErbB4 that is abundantly expressed in the brain, was able to rescue Lapatinib-induced apoptosis and clonogenic ability in BCBM94 and in HER2+ BT474. ErbB3 was essential to mediate the NRG1-induced survival pathway that involved PI3K-AKT signalling and the phosphorylation of BAD at serine 136 to prevent apoptosis. High throughput RTKi screening identified the brain penetrable Poziotinib as highly potent compound to reduce cell viability in HER2+ BCBM in the presence of NRG1. Successful in-vivo ablation of BCBM94- and BT474-derived HER2+ brain tumors was achieved upon two weeks of treatment with Poziotinib. MRI revealed BCBM remission upon poziotinib, but not with Lapatinib treatment. In conclusion, we have established a new patient-derived HER2+ BCBM in-vivo model and identified Poziotinib as highly efficacious RTKi with excellent brain penetrability that abrogated HER2+ BCBM brain tumors in our mouse models.

3.
Bioorg Med Chem Lett ; 22(5): 1903-7, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22330635

RESUMO

Thermosensitive transient receptor potential melastatin 8 (TRPM8) antagonists are considered to be potential therapeutic agents for the treatment of cold hypersensitivity. The discovery of a new class of TRPM8 antagonists that shows in vivo efficacy in the rat chronic constriction injury (CCI)-induced model of neuropathic pain is described.


Assuntos
Analgésicos/química , Analgésicos/uso terapêutico , Benzimidazóis/química , Benzimidazóis/uso terapêutico , Hiperalgesia/tratamento farmacológico , Neuralgia/tratamento farmacológico , Canais de Cátion TRPM/antagonistas & inibidores , Analgésicos/farmacocinética , Analgésicos/farmacologia , Animais , Benzimidazóis/farmacocinética , Benzimidazóis/farmacologia , Temperatura Baixa , Cães , Células HEK293 , Humanos , Ratos , Canais de Cátion TRPM/metabolismo
4.
Sci Total Environ ; 805: 150319, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34818811

RESUMO

This paper presents a comprehensive and practical method for Sustainable Agricultural Drainage Systems (SADS) design. It is aimed at studying the suitability of using surface runoff as irrigation source. The method determines the optimum amount of surface runoff to be used for irrigation considering both environmental constraints (aquifers recharge, discharge to natural water courses) and investment and operation costs. The developed method has been applied to the Spanish irrigation district "Villalar de los Comuneros Sector 1" located in Valladolid. The estimation of the optimum SADS provision was calculated for most of the major crops at the irrigation district highlighting that SADS facilities can reduce the amount of external provision of water for irrigation while maintaining the aquifer's recharge and the natural discharge to water courses. The simulations run for climate change forecasting scenarios (Representative Concentration Pathways, RCP, RCP45, RCP60, RCP85) showed that optimum SADS would reduce irrigation requirements and would increase natural fluxes (both aquifers and natural water courses) therefore improving the general water cycle in rural environments with productive agriculture.


Assuntos
Irrigação Agrícola , Mudança Climática , Agricultura , Produtos Agrícolas , Abastecimento de Água
5.
J Dent ; 126: 104301, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36150430

RESUMO

OBJECTIVES: To evaluate the diagnostic reliability of a web-based Artificial Intelligence program on the detection and classification of dental structures and treatments present on panoramic radiographs. METHODS: A total of 300 orthopantomographies (OPG) were randomly selected for this study. First, the images were visually evaluated by two calibrated operators with radiodiagnosis experience that, after consensus, established the "ground truth". Operators' findings on the radiographs were collected and classified as follows: metal restorations (MR), resin-based restorations (RR), endodontic treatment (ET), Crowns (C) and Implants (I). The orthopantomographies were then anonymously uploaded and automatically analyzed by the web-based software (Denti.Ai). Results were then stored, and a statistical analysis was performed by comparing them with the ground truth in terms of Sensitivity (S), Specificity (E), Positive Predictive Value (PPV) Negative Predictive Value (NPV) and its later representation in the area under (AUC) the Receiver Operating Characteristic (ROC) Curve. RESULTS: Diagnostic metrics obtained for each study variable were as follows: (MR) S=85.48%, E=87.50%, PPV=82.8%, NPV=42.51%, AUC=0.869; (PR) S=41.11%, E=93.30%, PPV=90.24%, NPV=87.50%, AUC=0.672; (ET) S=91.9%, E=100%, PPV=100%, NPV=94.62%, AUC=0.960; (C) S=89.53%, E=95.79%, PPV=89.53%, NPV=95.79%, AUC=0.927; (I) S, E, PPV, NPV=100%, AUC=1.000. CONCLUSIONS: Findings suggest that the web-based Artificial intelligence software provides a good performance on the detection of implants, crowns, metal fillings and endodontic treatments, not being so accurate on the classification of dental structures or resin-based restorations. CLINICAL SIGNIFICANCE: General diagnostic and treatment decisions using orthopantomographies can be improved by using web-based artificial intelligence tools, avoiding subjectivity and lapses from the clinician.


Assuntos
Inteligência Artificial , Software , Radiografia Panorâmica , Reprodutibilidade dos Testes , Curva ROC , Internet
6.
iScience ; 25(9): 104941, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36065186

RESUMO

Numerous studies have established the involvement of lysosomal and mitochondrial dysfunction in the pathogenesis of neurodegenerative disorders such as Alzheimer's and Parkinson diseases. Building on our previous studies of the neurodegenerative lysosomal lipidosis Niemann-Pick C1 (NPC1), we have unexpectedly discovered that activation of the mitochondrial chaperone tumor necrosis factor receptor-associated protein 1 (TRAP1) leads to the correction of the lysosomal storage phenotype in patient cells from multiple lysosomal storage disorders including NPC1. Using small compound activators specific for TRAP1, we find that activation of this chaperone leads to a generalized restoration of lysosomal and mitochondrial health. Mechanistically, we show that this process includes inhibition of oxidative phosphorylation and reduction of oxidative stress, which results in activation of AMPK and ultimately stimulates lysosome recycling. Thus, TRAP1 participates in lysosomal-mitochondrial crosstalk to maintain cellular homeostasis and could represent a potential therapeutic target for multiple disorders.

7.
Comput Methods Programs Biomed ; 202: 105958, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33588253

RESUMO

BACKGROUND AND OBJECTIVE: Nanoparticles present properties that can be applied to a wide range of fields such as biomedicine, electronics or optics. The type of properties depends on several characteristics, being some of them related with the particle structure. A proper characterization of nanoparticles is crucial since it could affect their applications. To characterize a particle shape and size, the nanotechnologists employ Electron Microscopy (EM) to obtain images of nanoparticles and perform measures over them. This task could be tedious, repetitive and slow, we present a Deep Learning method based on Convolutional Neural Networks (CNNs) to detect, segment, infer orientations and reconstruct microscope images of nanoparticles. Since machine learning algorithms depend on annotated data and there is a lack of annotated datasets of nanoparticles, our work makes use of artificial datasets of images resembling real nanoparticles photographs. METHODS: Our work is divided into three tasks. Firstly, a method to create annotated datasets of artificial images resembling Scanning Electron Microscope (SEM). Secondly, two models of convolutional neural networks are trained using the artificial datasets previously generated, the first one is in charge of the detection and segmentation of the nanoparticles while the second one will infer the nanoparticle orientation. Finally, the 3D reconstruction module will recreate in a 3D scene the set of detected particles. RESULTS: We have tested our method with five different shapes of basic nanoparticles: spheres, cubes, ellipsoids, hexagonal discs and octahedrons. An analysis of the reconstructions was conducted by manually comparing each of them with the real images. The results obtained have been promising, the particles are segmented and reconstructed accordingly to their shapes and orientations. CONCLUSIONS: We have developed a method for nanoparticle detection and segmentation in microscope images. Moreover, we can also infer an approximation of the 3D orientation of the particles and, in conjunction with the detections, create a 3D reconstruction of the photographs. The novelty of our approximation lies in the dataset used. Instead of using annotated images, we have created the datasets simulating the microscope images by using basic geometrical objects that imitate real nanoparticles.


Assuntos
Aprendizado Profundo , Nanopartículas , Processamento de Imagem Assistida por Computador , Microscopia Eletrônica , Redes Neurais de Computação
8.
Health Informatics J ; 26(4): 2722-2736, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32674723

RESUMO

Retinopathy of prematurity is a disease that can affect premature or in similar conditions babies. For diagnosing of retinopathy of prematurity, the infant is examined as soon as possible. Due to the nature of the examination, the images obtained are poor in quality. This article presents an automated method for processing fundus images to improve the visibility of the vascular network. The method includes several processing tasks whose parameters are predicted using an artificial neural network. A set of 88 clinical images were used in this work. The performance of our proposal is efficient, and the average processing time was 42 ms. The method was assessed using both the contrast improvement index and expert opinions. The contrast improvement index average was 2; this means the processed image successfully improved its contrast. Three pediatric ophthalmologists validated the proposed method and agreed that the visual enhancement can help observe clearly the retinal vessels.


Assuntos
Retinopatia da Prematuridade , Criança , Fundo de Olho , Humanos , Lactente , Recém-Nascido , Redes Neurais de Computação , Vasos Retinianos/diagnóstico por imagem , Retinopatia da Prematuridade/diagnóstico por imagem
9.
Sci Adv ; 6(6): eaaz2736, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32128386

RESUMO

Duchenne muscular dystrophy (DMD) is a devastating disease caused by mutations in dystrophin that compromise sarcolemma integrity. Currently, there is no treatment for DMD. Mutations in transient receptor potential mucolipin 1 (ML1), a lysosomal Ca2+ channel required for lysosomal exocytosis, produce a DMD-like phenotype. Here, we show that transgenic overexpression or pharmacological activation of ML1 in vivo facilitates sarcolemma repair and alleviates the dystrophic phenotypes in both skeletal and cardiac muscles of mdx mice (a mouse model of DMD). Hallmark dystrophic features of DMD, including myofiber necrosis, central nucleation, fibrosis, elevated serum creatine kinase levels, reduced muscle force, impaired motor ability, and dilated cardiomyopathies, were all ameliorated by increasing ML1 activity. ML1-dependent activation of transcription factor EB (TFEB) corrects lysosomal insufficiency to diminish muscle damage. Hence, targeting lysosomal Ca2+ channels may represent a promising approach to treat DMD and related muscle diseases.


Assuntos
Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Distrofia Muscular de Duchenne/metabolismo , Canais de Potencial de Receptor Transitório/agonistas , Animais , Biomarcadores , Biópsia , Modelos Animais de Doenças , Distrofina/genética , Imunofluorescência , Expressão Gênica , Camundongos , Camundongos Endogâmicos mdx , Camundongos Transgênicos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Distrofia Muscular de Duchenne/tratamento farmacológico , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/patologia , Miocárdio/metabolismo , Miocárdio/patologia
10.
Sci Transl Med ; 12(530)2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051227

RESUMO

Solid tumors elicit a detectable immune response including the infiltration of tumor-associated macrophages (TAMs). Unfortunately, this immune response is co-opted into contributing toward tumor growth instead of preventing its progression. We seek to reestablish an antitumor immune response by selectively targeting surface receptors and endogenous signaling processes of the macrophage subtypes driving cancer progression. RP-182 is a synthetic 10-mer amphipathic analog of host defense peptides that selectively induces a conformational switch of the mannose receptor CD206 expressed on TAMs displaying an M2-like phenotype. RP-182-mediated activation of this receptor in human and murine M2-like macrophages elicits a program of endocytosis, phagosome-lysosome formation, and autophagy and reprograms M2-like TAMs to an antitumor M1-like phenotype. In syngeneic and autochthonous murine cancer models, RP-182 suppressed tumor growth, extended survival, and was an effective combination partner with chemo- or immune checkpoint therapy. Antitumor activity of RP-182 was also observed in CD206high patient-derived xenotransplantation models. Mechanistically, via selective reduction of immunosuppressive M2-like TAMs, RP-182 improved adaptive and innate antitumor immune responses, including increased cancer cell phagocytosis by reprogrammed TAMs.


Assuntos
Lectinas de Ligação a Manose , Macrófagos Associados a Tumor , Animais , Linhagem Celular Tumoral , Humanos , Imunidade Inata , Lectinas Tipo C , Receptor de Manose , Camundongos , Receptores de Superfície Celular
11.
AMIA Annu Symp Proc ; 2019: 457-466, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32308839

RESUMO

The integration of genetic information in current clinical routine has raised a need for tools to exploit family genetic knowledge. On the clinical side, an application for managing and visualizing pedigree diagrams could provide genetics specialists with an integrated environment with potential positive impact on their current practice. This article presents a web tool (genoDraw) that provides clinical practitioners with the ability to create, maintain and visualize patients' and their families' information in the form of pedigree diagrams. genoDraw implements a graph-based three-step process for generating diagrams according to a de facto standard in the area and clinical terminologies. It also complies with five characteristics identified as indispensable for the next-generation of pedigree drawing software: comprehensiveness, data-drivenness, automation, interactivity and compatibility with biomedical vocabularies. The platform was implemented and tested, confirming its potential interest to clinical routine.


Assuntos
Ontologias Biológicas , Gráficos por Computador , Linhagem , Terminologia como Assunto , Humanos , Internet , Software , Vocabulário Controlado
12.
Elife ; 82019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31825310

RESUMO

Mammalian two-pore-channels (TPC1, 2; TPCN1, TPCN2) are ubiquitously- expressed, PI(3,5)P2-activated, Na+-selective channels in the endosomes and lysosomes that regulate luminal pH homeostasis, membrane trafficking, and Ebola viral infection. Whereas the channel activity of TPC1 is strongly dependent on membrane voltage, TPC2 lacks such voltage dependence despite the presence of the presumed 'S4 voltage-sensing' domains. By performing high-throughput screening followed by lysosomal electrophysiology, here we identified a class of tricyclic anti-depressants (TCAs) as small-molecule agonists of TPC channels. TCAs activate both TPC1 and TPC2 in a voltage-dependent manner, referred to as Lysosomal Na+ channel Voltage-dependent Activators (LyNa-VAs). We also identified another compound which, like PI(3,5)P2, activates TPC2 independent of voltage, suggesting the existence of agonist-specific gating mechanisms. Our identification of small-molecule TPC agonists should facilitate the studies of the cell biological roles of TPCs and can also readily explain the reported effects of TCAs in the modulation of autophagy and lysosomal functions.


Assuntos
Antidepressivos Tricíclicos/farmacologia , Agonistas dos Canais de Cálcio/farmacologia , Canais de Cálcio/metabolismo , Lisossomos/enzimologia , Animais , Canais de Cálcio/genética , Linhagem Celular , Análise Mutacional de DNA , Humanos , Mutagênese Sítio-Dirigida , Fosfatos de Fosfatidilinositol/farmacologia
13.
Bioorg Med Chem Lett ; 18(16): 4569-72, 2008 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-18662879

RESUMO

A series of piperidine carboxamides were developed as potent antagonists of the transient receptor potential vanilloid-1 (TRPV1), an emerging target for the treatment of pain. A focused library of polar head groups led to the identification of a benzoxazinone amide that afforded good potency in cell-based assays. Synthesis and a QSAR model will be presented.


Assuntos
Amidas/química , Benzoxazinas/farmacologia , Piperidinas/química , Canais de Cátion TRPV/antagonistas & inibidores , Benzoxazinas/química , Capsaicina/química , Proteínas de Transporte/antagonistas & inibidores , Química Farmacêutica/métodos , Desenho de Fármacos , Humanos , Concentração Inibidora 50 , Modelos Químicos , Conformação Molecular , Ligação Proteica , Relação Quantitativa Estrutura-Atividade , Relação Estrutura-Atividade
14.
Artigo em Inglês | MEDLINE | ID: mdl-30544845

RESUMO

The Internet and social media is an enormous source of information. Health social networks and online collaborative environments enable users to create shared content that afterwards can be discussed. The aim of this paper is to present a novel methodology designed for quantifying relevant information provided by different participants in clinical online discussions. The main goal of the methodology is to facilitate the comparison of participant interactions in clinical conversations. A set of key indicators for different aspects of clinical conversations and specific clinical contributions within a discussion have been defined. Particularly, three new indicators have been proposed to make use of biomedical knowledge extraction based on standard terminologies and ontologies. These indicators allow measuring the relevance of information of each participant of the clinical conversation. Proposed indicators have been applied to one discussion extracted from PatientsLikeMe, as well as to two real clinical cases from the Sanar collaborative discussion system. Results obtained from indicators in the tested cases have been compared with clinical expert opinions to check indicators validity. The methodology has been successfully used for describing participant interactions in real clinical cases belonging to a collaborative clinical case discussion tool and from a conversation from a health social network. This work can be applied to assess collaborative diagnoses, discussions among patients, and the participation of students in clinical case discussions. It permits moderators and educators to obtain a quantitatively measure of the contribution of each participant.


Assuntos
Sistemas de Informação em Saúde , Pessoal de Saúde , Mídias Sociais , Acesso à Informação , Comunicação , Tomada de Decisões , Sistemas de Informação em Saúde/normas , Humanos , Internet
15.
Evol Bioinform Online ; 14: 1176934318767889, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29662297

RESUMO

Understanding the regulation of gene expression is one of the key problems in current biology. A promising method for that purpose is the determination of the temporal dynamics between known initial and ending network states, by using simple acting rules. The huge amount of rule combinations and the nonlinear inherent nature of the problem make genetic algorithms an excellent candidate for finding optimal solutions. As this is a computationally intensive problem that needs long runtimes in conventional architectures for realistic network sizes, it is fundamental to accelerate this task. In this article, we study how to develop efficient parallel implementations of this method for the fine-grained parallel architecture of graphics processing units (GPUs) using the compute unified device architecture (CUDA) platform. An exhaustive and methodical study of various parallel genetic algorithm schemes-master-slave, island, cellular, and hybrid models, and various individual selection methods (roulette, elitist)-is carried out for this problem. Several procedures that optimize the use of the GPU's resources are presented. We conclude that the implementation that produces better results (both from the performance and the genetic algorithm fitness perspectives) is simulating a few thousands of individuals grouped in a few islands using elitist selection. This model comprises 2 mighty factors for discovering the best solutions: finding good individuals in a short number of generations, and introducing genetic diversity via a relatively frequent and numerous migration. As a result, we have even found the optimal solution for the analyzed gene regulatory network (GRN). In addition, a comparative study of the performance obtained by the different parallel implementations on GPU versus a sequential application on CPU is carried out. In our tests, a multifold speedup was obtained for our optimized parallel implementation of the method on medium class GPU over an equivalent sequential single-core implementation running on a recent Intel i7 CPU. This work can provide useful guidance to researchers in biology, medicine, or bioinformatics in how to take advantage of the parallelization on massively parallel devices and GPUs to apply novel metaheuristic algorithms powered by nature for real-world applications (like the method to solve the temporal dynamics of GRNs).

16.
Urology ; 111: 139-144, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28916253

RESUMO

OBJECTIVE: To assess the role of transanal endoscopic operation (TEO) or transanal endoscopic microsurgery (TEM) in rectourethral fistulas (RUF). RUF may appear after radical prostatectomy. Their treatment represents a challenge; many therapies have been proposed, from conservative to aggressive surgical approaches. Transanal endoscopic surgery (TEO or TEM) is a minimally invasive technique to access the site of the RUF to perform repair. MATERIALS AND METHODS: This is an observational study with prospective data collection, conducted between September 2006 and December 2015. All patients were diagnosed with RUF following management of prostate cancer. Conservative treatment was administered in the form of urinary and fecal diversion with cystotomy and terminal colostomy, to achieve total urinary and fecal exclusion. If the fistula persisted, it was treated by TEO or TEM, with or without biological mesh interposition. If this failed, gracilis muscle was applied as salvage therapy. RESULTS: Ten patients were diagnosed with RUF. In 1 patient (1 of 10), the fistula healed with bladder catheterization alone. In another patient (1 of 9), it resolved after total urinary and fecal exclusion. Eight patients underwent repair by TEO or TEM, 4 with biological mesh interposition; all 4 presented recurrence. In the other 4 patients treated via TEO or TEM, 2 had early recurrence, whereas the others had healed at follow-up visits after 4-6 months (2 of 8)-a success rate of 25%. The 6 patients who recurred were treated with gracilis muscle interposition via a transperineal approach. CONCLUSION: The low rate of positive results obtained by TEO or TEM argues against its use as technique of choice in RUF, and against the use of biological meshes.


Assuntos
Fístula Retal/cirurgia , Cirurgia Endoscópica Transanal , Doenças Uretrais/cirurgia , Fístula Urinária/cirurgia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Urológicos/métodos
17.
Mol Cancer Ther ; 5(1): 160-9, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16432175

RESUMO

The activity and stability of the p53 tumor suppressor are regulated by the human homologue of the mouse double minute 2 (Hdm2) oncoprotein. It has been hypothesized that small molecules disrupting the Hdm2:p53 complex would allow for the activation of p53 and result in growth suppression. We have identified small-molecule inhibitors of the Hdm2:p53 interaction using our proprietary ThermoFluor microcalorimetry technology. Medicinal chemistry and structure-based drug design led to the development of an optimized series of benzodiazepinediones, including TDP521252 and TDP665759. Activities were dependent on the expression of wild-type (wt) p53 and Hdm2 as determined by lack of potency in mutant or null p53-expressing cell lines or cells engineered to no longer express Hdm2 and wt p53. TDP521252 and TDP665759 inhibited the proliferation of wt p53-expressing cell lines with average IC(50)s of 14 and 0.7 micromol/L, respectively. These results correlated with the direct cellular dissociation of Hdm2 from wt p53 observed within 15 minutes in JAR choriocarcinoma cells. Additional activities of these inhibitors in vitro include stabilization of p53 protein levels, up-regulation of p53 target genes in a DNA damage-independent manner, and induction of apoptosis in HepG2 cells. Administration of TDP665759 to mice led to an increase in p21(waf1/cip1) levels in liver samples. Finally, TDP665759 synergizes with doxorubicin both in culture and in an A375 xenograft model to decrease tumor growth. Taken together, these data support the potential utility of small-molecule inhibitors of the Hdm2:p53 interaction for the treatment of wt p53-expressing tumors.


Assuntos
Benzodiazepinonas/farmacologia , Doxorrubicina/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/efeitos dos fármacos , Proteína Supressora de Tumor p53/efeitos dos fármacos , Animais , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptose/efeitos dos fármacos , Benzodiazepinas/química , Benzodiazepinas/farmacologia , Benzodiazepinonas/administração & dosagem , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Feminino , Humanos , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/metabolismo , Camundongos , Camundongos Nus , Complexos Multiproteicos , Mutação , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
18.
J Biomed Semantics ; 8(1): 49, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28982381

RESUMO

BACKGROUND: Semantic interoperability is essential when carrying out post-genomic clinical trials where several institutions collaborate, since researchers and developers need to have an integrated view and access to heterogeneous data sources. One possible approach to accommodate this need is to use RDB2RDF systems that provide RDF datasets as the unified view. These RDF datasets may be materialized and stored in a triple store, or transformed into RDF in real time, as virtual RDF data sources. Our previous efforts involved materialized RDF datasets, hence losing data freshness. RESULTS: In this paper we present a solution that uses an ontology based on the HL7 v3 Reference Information Model and a set of R2RML mappings that relate this ontology to an underlying relational database implementation, and where morph-RDB is used to expose a virtual, non-materialized SPARQL endpoint over the data. CONCLUSIONS: By applying a set of optimization techniques on the SPARQL-to-SQL query translation algorithm, we can now issue SPARQL queries to the underlying relational data with generally acceptable performance.


Assuntos
Ontologias Biológicas , Bases de Dados Factuais , Armazenamento e Recuperação da Informação/métodos , Software , Algoritmos , Humanos , Internet , Semântica
19.
Dev Cell ; 41(3): 262-273.e6, 2017 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-28486130

RESUMO

Gastric acid secretion by parietal cells requires trafficking and exocytosis of H/K-ATPase-rich tubulovesicles (TVs) toward apical membranes in response to histamine stimulation via cyclic AMP elevation. Here, we found that TRPML1 (ML1), a protein that is mutated in type IV mucolipidosis (ML-IV), is a tubulovesicular channel essential for TV exocytosis and acid secretion. Whereas ML-IV patients are reportedly achlorhydric, transgenic overexpression of ML1 in mouse parietal cells induced constitutive acid secretion. Gastric acid secretion was blocked and stimulated by ML1 inhibitors and agonists, respectively. Organelle-targeted Ca2+ imaging and direct patch-clamping of apical vacuolar membranes revealed that ML1 mediates a PKA-activated conductance on TV membranes that is required for histamine-induced Ca2+ release from TV stores. Hence, we demonstrated that ML1, acting as a Ca2+ channel in TVs, links transmitter-initiated cyclic nucleotide signaling with Ca2+-dependent TV exocytosis in parietal cells, providing a regulatory mechanism that could be targeted to manage acid-related gastric diseases.


Assuntos
Cálcio/metabolismo , Membrana Celular/metabolismo , Exocitose/fisiologia , Ácido Gástrico/metabolismo , Células Parietais Gástricas/metabolismo , Animais , Transporte Biológico/fisiologia , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Histamina/metabolismo , Camundongos , Transdução de Sinais/fisiologia
20.
Comput Biol Med ; 87: 179-186, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28601027

RESUMO

INTRODUCTION: The introduction of omics data and advances in technologies involved in clinical treatment has led to a broad range of approaches to represent clinical information. Within this context, patient stratification across health institutions due to omic profiling presents a complex scenario to carry out multi-center clinical trials. METHODS: This paper presents a standards-based approach to ensure semantic integration required to facilitate the analysis of clinico-genomic clinical trials. To ensure interoperability across different institutions, we have developed a Semantic Interoperability Layer (SIL) to facilitate homogeneous access to clinical and genetic information, based on different well-established biomedical standards and following International Health (IHE) recommendations. RESULTS: The SIL has shown suitability for integrating biomedical knowledge and technologies to match the latest clinical advances in healthcare and the use of genomic information. This genomic data integration in the SIL has been tested with a diagnostic classifier tool that takes advantage of harmonized multi-center clinico-genomic data for training statistical predictive models. CONCLUSIONS: The SIL has been adopted in national and international research initiatives, such as the EURECA-EU research project and the CIMED collaborative Spanish project, where the proposed solution has been applied and evaluated by clinical experts focused on clinico-genomic studies.


Assuntos
Neoplasias da Mama/genética , Expressão Gênica , Semântica , Feminino , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA