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1.
Int J Mol Sci ; 25(2)2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38256096

RESUMO

Photodynamic therapy (PDT) is a two-stage treatment that implies the use of light energy, oxygen, and light-activated compounds (photosensitizers) to elicit cancerous and precancerous cell death after light activation (phototoxicity). The biophysical, bioengineering aspects and its combinations with other strategies are highlighted in this review, both conceptually and as they are currently applied clinically. We further explore the recent advancements of PDT with the use of nanotechnology, including quantum dots as innovative photosensitizers or energy donors as well as the combination of PDT with radiotherapy and immunotherapy as future promising cancer treatments. Finally, we emphasize the potential significance of organoids as physiologically relevant models for PDT.


Assuntos
Neoplasias , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Imunoterapia , Bioengenharia , Engenharia Biomédica , Neoplasias/tratamento farmacológico
2.
Cells ; 12(8)2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-37190034

RESUMO

BACKGROUND: The high recurrence of glioblastoma (GB) that occurs adjacent to the resection cavity within two years of diagnosis urges an improvement of therapies oriented to GB local control. Photodynamic therapy (PDT) has been proposed to cleanse infiltrating tumor cells from parenchyma to ameliorate short long-term progression-free survival. We examined 5-aminolevulinic acid (5-ALA)-mediated PDT effects as therapeutical treatment and determined optimal conditions for PDT efficacy without causing phototoxic injury to the normal brain tissue. METHODS: We used a platform of Glioma Initiation Cells (GICs) infiltrating cerebral organoids with two different glioblastoma cells, GIC7 and PG88. We measured GICs-5-ALA uptake and PDT/5-ALA activity in dose-response curves and the efficacy of the treatment by measuring proliferative activity and apoptosis. RESULTS: 5-ALA (50 and 100 µg/mL) was applied, and the release of protoporphyrin IX (PpIX) fluorescence measures demonstrated that the emission of PpIX increases progressively until its stabilization at 24 h. Moreover, decreased proliferation and increased apoptosis corroborated the effect of 5-ALA/PDT on cancer cells without altering normal cells. CONCLUSIONS: We provide evidence about the effectiveness of PDT to treat high proliferative GB cells in a complex in vitro system, which combines normal and cancer cells and is a useful tool to standardize new strategic therapies.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Fotoquimioterapia , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Técnicas de Cocultura , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Ácido Aminolevulínico/farmacologia , Ácido Aminolevulínico/uso terapêutico , Glioma/patologia , Encéfalo/patologia , Organoides
3.
Clin Transl Med ; 12(10): e1063, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36281739

RESUMO

The limited availability of red cells with extremely rare blood group phenotypes is one of the global challenges in transfusion medicine that has prompted the search for alternative self-renewable pluripotent cell sources for the in vitro generation of red cells with rare blood group types. One such phenotype is the Rhnull , which lacks all the Rh antigens on the red cell membrane and represents one of the rarest blood types in the world with only a few active blood donors available worldwide. Rhnull red cells are critical for the transfusion of immunized patients carrying the same phenotype, besides its utility in the diagnosis of Rh alloimmunization when a high-prevalence Rh specificity is suspected in a patient or a pregnant woman. In both scenarios, the potential use of human-induced pluripotent stem cell (hiPSC)-derived Rhnull red cells is also dependent on ABO compatibility. Here, we present a CRISPR/Cas9-mediated ABO gene edition strategy for the conversion of blood type A to universal type O, which we have applied to an Rhnull donor-derived hiPSC line, originally carrying blood group A. This work provides a paradigmatic example of an approach potentially applicable to other hiPSC lines derived from rare blood donors not carrying blood type O.


Assuntos
Antígenos de Grupos Sanguíneos , Células-Tronco Pluripotentes Induzidas , Feminino , Humanos , Sistema do Grupo Sanguíneo Rh-Hr/genética , Edição de Genes , Doadores de Sangue
4.
Cells ; 11(17)2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-36078122

RESUMO

IPSC-based disease modelling and pluripotency studies have sparked widespread enthusiasm for more than 16 years of research [...].


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Células-Tronco Pluripotentes Induzidas , Transplante de Células-Tronco
5.
Front Cell Dev Biol ; 10: 820255, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35652095

RESUMO

Characterization of pluripotent states, in which cells can both self-renew or differentiate, with the irreversible loss of pluripotency, are important research areas in developmental biology. Although microRNAs (miRNAs) have been shown to play a relevant role in cellular differentiation, the role of miRNAs integrated into gene regulatory networks and its dynamic changes during these early stages of embryonic stem cell (ESC) differentiation remain elusive. Here we describe the dynamic transcriptional regulatory circuitry of stem cells that incorporate protein-coding and miRNA genes based on miRNA array expression and quantitative sequencing of short transcripts upon the downregulation of the Estrogen Related Receptor Beta (Esrrb). The data reveals how Esrrb, a key stem cell transcription factor, regulates a specific stem cell miRNA expression program and integrates dynamic changes of feed-forward loops contributing to the early stages of cell differentiation upon its downregulation. Together these findings provide new insights on the architecture of the combined transcriptional post-transcriptional regulatory network in embryonic stem cells.

6.
Methods Mol Biol ; 2454: 559-574, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33190185

RESUMO

The realization of the full potential of human pluripotent stem cells (hPSCs), including human induced PSCs (iPSC), relies on the ability to precisely edit their genome in a locus-specific and multiplex manner. Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) serve as a guide for the endonuclease Cas9 (CRISPR-associated protein 9) to recognize and cleave specific strands of DNA that are complementary to the CRISPR sequence. CRISPR/Cas9-mediated editing has become the gold standard for precise genome manipulation as it offers a unique, versatile, and limitless tool for fast, robust, and efficient genome editing. Here, we provide a protocol to successfully generate gene knockout and/or knockin iPSCs. We include detailed information on the design of guide RNAs (gRNAs), T7 endonuclease assay to detect on-target CRISPR/Cas9 editing events, DNA electroporation of the iPSCs with a ribonucleoprotein complex, and single-cell cloning steps for the selection of the genome-edited iPSC clones.


Assuntos
Sistemas CRISPR-Cas , Células-Tronco Pluripotentes Induzidas , Sistemas CRISPR-Cas/genética , DNA/metabolismo , Endonucleases/genética , Endonucleases/metabolismo , Técnicas de Inativação de Genes , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , RNA Guia de Cinetoplastídeos/genética , RNA Guia de Cinetoplastídeos/metabolismo
7.
J Aging Phys Act ; 30(2): 323-331, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34453023

RESUMO

The aim of this study was to examine, theoretically, how reallocating time between the intensity of mutually exclusive categories of physical activity and sedentary behavior time is associated with metabolic syndrome. Four hundred and six older adults (61.6% women) from the second wave of the EpiFloripa Aging Cohort Study were included in the study (mean age 71.7 ± 5.9 years). Isotemporal substitution analysis showed a decrease of 35% (odds ratio: 0.65; 95% confidence interval [0.45, 0.96]) in the risk for metabolic syndrome when replacing 30 min/day of sedentary behavior with an equivalent amount of moderate to vigorous physical activity. Furthermore, it has been observed that older adults classified as low sedentary behavior and physically active were 57% less likely to have metabolic syndrome than participants classified as high sedentary and physically inactive (odds ratio: 0.43; 95% confidence interval [0.19, 0.97]). This study highlights the importance of behavioral categories that may emerge concerning the interrelationships of physical activity and health in older adults, having important implications for future health intervention programs.


Assuntos
Síndrome Metabólica , Comportamento Sedentário , Acelerometria , Idoso , Estudos de Coortes , Estudos Transversais , Exercício Físico , Feminino , Humanos , Masculino , Síndrome Metabólica/epidemiologia
8.
Front Cell Dev Biol ; 9: 630067, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33816475

RESUMO

Cell fate decisions during development are governed by multi-factorial regulatory mechanisms including chromatin remodeling, DNA methylation, binding of transcription factors to specific loci, RNA transcription and protein synthesis. However, the mechanisms by which such regulatory "dimensions" coordinate cell fate decisions are currently poorly understood. Here we quantified the multi-dimensional molecular changes that occur in mouse embryonic stem cells (mESCs) upon depletion of Estrogen related receptor beta (Esrrb), a key pluripotency regulator. Comparative analyses of expression changes subsequent to depletion of Esrrb or Nanog, indicated that a system of interlocked feed-forward loops involving both factors, plays a central part in regulating the timing of mESC fate decisions. Taken together, our meta-analyses support a hierarchical model in which pluripotency is maintained by an Oct4-Sox2 regulatory module, while the timing of differentiation is regulated by a Nanog-Esrrb module.

9.
Int J Cardiovasc Imaging ; 37(2): 509-515, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32959097

RESUMO

Regadenoson Stress Echocardiography (RSE) can detect myocardial ischemia, and its diagnostic accuracy should be evaluated. We sought to investigate the agreement between RSE and gated-SPECT myocardial perfusion imaging (MPI) and appraise its diagnostic accuracy. Consecutive patients (n = 202) referred for non-invasive evaluation of myocardial ischemia, with (38.6%) or without a previous coronary artery disease (CAD) diagnosis, were enrolled. Both tests were performed simultaneously. Invasive coronary angiography (CA) is considered the gold standard. The mean age was 70.9 (9.8) years, and 59.9% were male. The prevalence of cardiovascular risk factors (arterial hypertension [81.7%], diabetes mellitus [37.6%], hypercholesterolemia [71.8%], and smoking [18.8%]) was high. Forty-four patients (21.8%) had a non-interpretable electrocardiogram, 15 (34.1%) of them were a result of ventricular paced-rhythm, while 29 (65.9%) were a result of advanced left ventricular branch block. The overall agreement between both diagnostic techniques was good: Gwet's AC1 0.66 (CI95% 0.55 to 0.76), and it was higher in patients without a previous CAD diagnosis: 0.76 (CI95% 0.65 to 0.87). In the biased sample (those who underwent CA), RSE and nuclear study sensitivity was 0.50 and 0.78 and specificity was 0.75 and 0.75, respectively. We noted a dramatic reduction in sensitivity for RSE after debiasing (debiased sensitivity of 0.16), and the negative predictive value was similar to the biased and debiased samples. RSE is in strong agreement with gated-SPECT MPI. However, its low sensitivity and negative predictive value preclude its use as a bedside test to detect myocardial ischemia.


Assuntos
Ecocardiografia sob Estresse , Isquemia Miocárdica/diagnóstico por imagem , Imagem de Perfusão do Miocárdio , Purinas , Pirazóis , Tomografia Computadorizada de Emissão de Fóton Único , Vasodilatadores , Idoso , Técnicas de Imagem de Sincronização Cardíaca , Comorbidade , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/fisiopatologia , Compostos Organofosforados , Compostos de Organotecnécio , Valor Preditivo dos Testes , Prevalência , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Fumar/efeitos adversos , Fumar/epidemiologia , Tecnécio Tc 99m Sestamibi
11.
Psicooncología (Pozuelo de Alarcón) ; 17(2): 335-355, jul.-dic. 2020. tab
Artigo em Espanhol | IBECS | ID: ibc-199119

RESUMO

OBJETIVO: Identificar la eficacia de los tratamientos musicoterapéuticos que aborden la sintomatología en pacientes con cáncer y que constaten algún tipo de beneficio psicológico, fisiológico, espiritual, social o intelectual. MÉTODO: Se realizó un análisis documental que supuso un estudio comparativo de evidencias científicas. RESULTADOS: La musicoterapia minimiza los efectos fisiológicos de tratamientos específicos oncológicos como la quimioterapia, se usa como complemento de la morfina o el sufentanilo disminuyendo el dolor e influye en la vida emocional del paciente. CONCLUSIONES: Es una disciplina que demuestra evidencias positivas en situaciones de tipo emocional reduciendo la depresión, la ansiedad y el estrés, ayudando en la relajación y mejorando el umbral del dolor, postulándose como una opción no-farmacológica que debiera conducir a una implantación cada vez más normalizada en los centros hospitalarios


OBJECTIVE: To identify the efficacy of music therapy treatments that address symptoms in cancer patients and show some type of psychological, physiological, spiritual, social or intellectual benefit. METHOD: A documentary analysis was carried out that involved a comparative study of scientific evidence. RESULTS: Music therapy minimizes the physiological effects of specific oncological treatments such as chemotherapy, it is used as a complement to morphine or sufentanil, reducing pain and influencing the emotional life of the patient. CONCLUSIONS: It is a discipline that shows positive evidence in emotional situations reducing depression, anxiety and stress, helping in relaxation and improving the pain threshold, postulating itself as a non-pharmacological option that should lead to an implantation every time. more standardized in hospital centers


Assuntos
Humanos , Terapias Complementares , Musicoterapia/métodos , Qualidade de Vida/psicologia , Neoplasias/psicologia , Neoplasias/terapia , Medicina Baseada em Evidências
12.
Front Cell Neurosci ; 14: 209, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32848613

RESUMO

Neuroinflammation constitutes a fundamental cellular process to signal the loss of brain homeostasis. Glial cells play a central role in orchestrating these neuroinflammation processes in both deleterious and beneficial ways. These cellular responses depend on their intercellular interactions with neurons, astrocytes, the blood-brain barrier (BBB), and infiltrated T cells in the central nervous system (CNS). However, this intercellular crosstalk seems to be activated by specific stimuli for each different neurological scenario. This review summarizes key studies linking neuroinflammation with certain neurodegenerative diseases such as Alzheimer disease (AD), Parkinson disease (PD), and amyotrophic lateral sclerosis (ALS) and for the development of better therapeutic strategies based on immunomodulation.

13.
Sci Context ; 33(4): 423-440, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-35086592

RESUMO

This article examines the medical and political discussions regarding a controversial medicinal bark from Ecuador - cundurango - that was actively sponsored by the Ecuadorian government as a new botanical cure for cancer in the late nineteenth century United States and elsewhere. The article focuses on the commercial and diplomatic interests behind the public discussion and advertising techniques of this drug. It argues that diverse elements - including the struggle for positioning scientific societies and the disapproval of the capacities of Ecuadorian doctors, US abolitionist history, regional and local political struggles - played a role in the quackery accusations against cundurango and its promoters. The development and international trade of this remedy offer interesting insights into the global history of drugs, particularly how medical knowledge was challenged during a period when scientific medicine was struggling for hegemony. It explores how newspapers expanded "the public interest" in a possible cancer cure.


Assuntos
Médicos , Charlatanismo , Comércio , História do Século XIX , História do Século XX , Humanos , Internacionalidade , Conhecimento , Médicos/história , Charlatanismo/história , Estados Unidos
15.
Nat Commun ; 10(1): 4155, 2019 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-31519912

RESUMO

Zika virus (ZIKV) infection results in an increased risk of spontaneous abortion and poor intrauterine growth although the underlying mechanisms remain undetermined. Little is known about the impact of ZIKV infection during the earliest stages of pregnancy, at pre- and peri-implantation, because most current ZIKV pregnancy studies have focused on post-implantation stages. Here, we demonstrate that trophectoderm cells of pre-implantation human and mouse embryos can be infected with ZIKV, and propagate virus causing neural progenitor cell death. These findings are corroborated by the dose-dependent nature of ZIKV susceptibility of hESC-derived trophectoderm cells. Single blastocyst RNA-seq reveals key transcriptional changes upon ZIKV infection, including nervous system development, prior to commitment to the neural lineage. The pregnancy rate of mice is >50% lower in pre-implantation infection than infection at E4.5, demonstrating that pre-implantation ZIKV infection leads to miscarriage. Cumulatively, these data elucidate a previously unappreciated association of pre- and peri-implantation ZIKV infection and microcephaly.


Assuntos
Complicações Infecciosas na Gravidez/metabolismo , Infecção por Zika virus/complicações , Infecção por Zika virus/metabolismo , Zika virus/patogenicidade , Aborto Espontâneo/metabolismo , Aborto Espontâneo/fisiopatologia , Animais , Blastocisto/citologia , Blastocisto/metabolismo , Implantação do Embrião/fisiologia , Feminino , Desenvolvimento Fetal/genética , Desenvolvimento Fetal/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , RNA Viral/genética , Pesquisa Translacional Biomédica/métodos , Trofoblastos/citologia , Trofoblastos/metabolismo
16.
Biochim Biophys Acta Gene Regul Mech ; 1862(3): 240-252, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30593929

RESUMO

The recent advent of high-throughput sequencing technologies coupled with RNA modifications detection methods has allowed the detection of RNA modifications at single nucleotide resolution giving a more comprehensive landscape of post-transcriptional gene regulation pathways. In this review, we focus on the occurrence of 5-methylcytosine (m5C) in the transcriptome. We summarise the main findings of the molecular role in post-transcriptional regulation that governs m5C deposition in RNAs. Functionally, m5C deposition can regulate several cellular and physiological processes including development, differentiation and survival to stress stimuli. Despite many aspects concerning m5C deposition in RNA, such as position or sequence context and the fact that many readers and erasers still remain elusive, the overall recent findings indicate that RNA cytosine methylation is a powerful mechanism to post-transcriptionally regulate physiological processes. In addition, mutations in RNA cytosine-5 methyltransferases are associated to pathological processes ranging from neurological syndromes to cancer.


Assuntos
5-Metilcitosina/metabolismo , Processamento Pós-Transcricional do RNA , RNA Mensageiro/metabolismo , RNA não Traduzido/metabolismo , Animais , Humanos , Metiltransferases/genética , Metiltransferases/metabolismo , RNA Mensageiro/genética , RNA não Traduzido/genética
17.
Stem Cell Res ; 29: 197-201, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29730569

RESUMO

The human embryonic stem cell line NYSCFe002-A was derived from a day 6 blastocyst in feeder-free and antibiotic free conditions. The blastocyst was voluntarily donated for research as surplus after in vitro fertilization treatment following informed consent. The NYSCFe002-A line expresses all the pluripotency markers and has the potential to differentiate into all three germ layers in vitro. The line presents normal karyotype and is mycoplasma free. This line is registered as NYSCF101 on the NIH Registry.


Assuntos
Antígenos de Diferenciação/biossíntese , Células-Tronco Embrionárias Humanas , National Institutes of Health (U.S.) , Sistema de Registros , Linhagem Celular , Feminino , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Estados Unidos
18.
Stem Cell Res ; 29: 99-102, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29631040

RESUMO

The human embryonic stem cell line NYSCFe001-A was derived from a day 6 blastocyst in feeder-free and antibiotic free conditions. The blastocyst was voluntarily donated for research as surplus after in vitro fertilization treatment following informed consent. The NYSCFe001-A line, registered as NYSCF100 on the NIH registry, presents normal karyotype, is mycoplasma free, expresses all the pluripotency markers and has the potential to differentiate into all three germ layers in vitro.


Assuntos
Células-Tronco Embrionárias Humanas/metabolismo , Linhagem Celular , Humanos , National Institutes of Health (U.S.) , Sistema de Registros , Estados Unidos
19.
Stem Cell Res ; 25: 217-220, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29161648

RESUMO

The human embryonic stem cell line NYSCFe003-A was derived from a day 5 to day 6 blastocyst in feeder-free and antibiotic free conditions. The blastocyst was voluntarily donated for research as surplus after in vitro fertilization treatment following informed consent. The NYSCFe003-A line expresses all the pluripotency markers and has the potential to differentiate into all three germ layers in vitro. The line presents normal karyotype and is mycoplasma free.


Assuntos
Células-Tronco Embrionárias Humanas/citologia , Blastocisto/citologia , Linhagem Celular , Células Cultivadas , Genótipo , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Cariótipo , Masculino , Microscopia de Fluorescência
20.
Stem Cell Investig ; 3: 86, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28066788

RESUMO

Induced pluripotent stem cells (iPSCs) are being generated using various reprogramming methods and from different cell sources. Hence, a lot of effort has been devoted to evaluating the differences among iPSC lines, in particular with respect to their differentiation capacity. While line-to-line variability should mainly reflect the genetic diversity within the human population, here we review some studies that have brought attention to additional variation caused by genomic and epigenomic alterations. We discuss strategies to evaluate aberrant changes and to minimize technical and culture-induced noise, in order to generate safe cells for clinical applications. We focus on the findings from a recent study, which compared the differentiation capacity of several iPSC lines committed to the hematopoietic lineage and correlated the differential maturation capacity with aberrant DNA methylations. Although iPSC variation represents a challenge for the field, we embrace the authors' perspective that iPSC variations should be used to our advantage for predicting and selecting the best performing iPSC lines, depending on the desired application.

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