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1.
Iberoam. j. med ; 6(2): 60-68, 2024. tab, graf
Artigo em Inglês | IBECS | ID: ibc-232597

RESUMO

Introduction: The use of antibiotic-loaded cement is an intraoperative tool that has demonstrated potential benefits in hip arthroplasty. However, the global landscape of research on this topic remains unknown. The objective of this study was to analyze the scientific growth, characteristics, and metrics of global and historical research on the use of antibiotic-loaded cement in hip arthroplasty. Material and methods: A cross-sectional bibliometric study was conducted using Scopus as the data source. Results: A total of 523 documents published between 1973 and 2023 were selected. 89.9% (n=470) of the production consisted of original articles, with 11.85% being multi-center. 84.1% of the authors have published a single article, followed by 10.3% who have published two articles. Research has predominantly focused on adults or the elderly, with an emphasis on outcome evaluation (notably reoperation), assessing various antibiotic agents, and frequently employing retrospective designs. Conclusions: There has been a sustained increase in research on the use of antibiotic-loaded cement in hip arthroplasty over the last 50 years. The research trend has shifted towards the evaluation of adult or elderly patients, exploration of antimicrobial agents, techniques, and health outcomes, primarily using observational and retrospective designs. An emerging research-focus is the study of hip arthroplasty in rheumatoid arthritis patients. (AU)


Introducción: El uso de cemento cargado con antibiótico, es una herramienta intraoperatoria que ha demostrado potenciales beneficios en la artroplastia de cadera. Sin embargo, se desconoce el panorama global de la investigación sobre este tópico. El objetivo de este estudio fue analizar el crecimiento científico, características y métricas de la investigación global e histórica sobre el uso de cemento cargado con antibiótico en artroplastia de cadera. Material y métodos: Estudio bibliométrico de corte transversal, que utilizó como fuente de datos la base Scopus. Resultados: Se seleccionaron 523 documentos publicados entre 1973 y 2023. El 89,9% (n=470) de la producción consistió en artículos originales, siendo el 11,85% multicéntricos. El 84,1% de los autores han publicado un único artículo, seguido de un 10,3% que han publicado dos artículos. La investigación se ha centrado predominantemente en adultos o ancianos, con énfasis en la evaluación de resultados (especialmente la reoperación), evaluando diversos agentes antibióticos y empleando con frecuencia diseños retrospectivos. Conclusiones: En los últimos 50 años se ha producido un aumento sostenido de la investigación sobre el uso de cemento cargado con antibióticos en la artroplastia de cadera. La tendencia de la investigación se ha desplazado hacia la evaluación de pacientes adultos o ancianos, la exploración de los agentes antimicrobianos, las técnicas y los resultados sanitarios, utilizando principalmente diseños observacionales y retrospectivos. Un nuevo foco de investigación es el estudio de la artroplastia de cadera en pacientes con artritis reumatoide. (AU)


Assuntos
Humanos , Cimentos Ósseos/farmacologia , Cimentos Ósseos/uso terapêutico , Antibacterianos , Bibliometria , Artroplastia , Artroplastia de Quadril
2.
Nat Commun ; 13(1): 7951, 2022 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-36572684

RESUMO

Pancreatic islet transplantation efficacy for type 1 diabetes (T1D) management is limited by hypoxia-related graft attrition and need for systemic immunosuppression. To overcome these challenges, we developed the Neovascularized Implantable Cell Homing and Encapsulation (NICHE) device, which integrates direct vascularization for facile mass transfer and localized immunosuppressant delivery for islet rejection prophylaxis. Here, we investigated NICHE efficacy for allogeneic islet transplantation and long-term diabetes reversal in an immunocompetent, male rat model. We demonstrated that allogeneic islets transplanted within pre-vascularized NICHE were engrafted, revascularized, and functional, reverting diabetes in rats for over 150 days. Notably, we confirmed that localized immunosuppression prevented islet rejection without inducing toxicity or systemic immunosuppression. Moreover, for translatability efforts, we showed NICHE biocompatibility and feasibility of deployment as well as short-term allogeneic islet engraftment in an MHC-mismatched nonhuman primate model. In sum, the NICHE holds promise as a viable approach for safe and effective islet transplantation and long-term T1D management.


Assuntos
Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Ratos , Animais , Masculino , Diabetes Mellitus Tipo 1/terapia , Terapia de Imunossupressão , Tolerância Imunológica , Imunossupressores/farmacologia , Sobrevivência de Enxerto
3.
Mater Today Bio ; 16: 100390, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36033374

RESUMO

Local immunomodulation has shown the potential to control the immune response in a site-specific manner for wound healing, cancer, allergy, and cell transplantation, thus abrogating adverse effects associated with systemic administration of immunotherapeutics. Localized immunomodulation requires confining the biodistribution of immunotherapeutics on-site for maximal immune control and minimal systemic drug exposure. To this end, we developed a 3D-printed subcutaneous implant termed 'NICHE', consisting of a bioengineered vascularized microenvironment enabled by sustained drug delivery on-site. The NICHE was designed as a platform technology for investigating local immunomodulation in the context of cell therapeutics and cancer vaccines. Here we studied the ability of the NICHE to localize the PK and biodistribution of different model immunomodulatory agents in vivo. For this, we first performed a mechanistic evaluation of the microenvironment generated within and surrounding the NICHE, with emphasis on the parameters related to molecular transport. Second, we longitudinally studied the biodistribution of ovalbumin, cytotoxic T lymphocyte-associated antigen-4-Ig (CTLA4Ig), and IgG delivered locally via NICHE over 30 days. Third, we used our findings to develop a physiologically-based pharmacokinetic (PBPK) model. Despite dense and mature vascularization within and surrounding the NICHE, we showed sustained orders of magnitude higher molecular drug concentrations within its microenvironment as compared to systemic circulation and major organs. Further, the PBPK model was able to recapitulate the biodistribution of the 3 molecules with high accuracy (r â€‹> â€‹0.98). Overall, the NICHE and the PBPK model represent an adaptable platform for the investigation of local immunomodulation strategies for a wide range of biomedical applications.

4.
Expert Opin Drug Deliv ; 19(5): 595-610, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35588058

RESUMO

INTRODUCTION: Cell transplantation is a promising curative therapeutic strategy whereby impaired organ function can be restored without the need for whole-organ transplantation. A key challenge in allotransplantation is the requirement for life-long systemic immunosuppression to prevent rejection, which is associated with serious adverse effects such as increased risk of opportunistic infections and the development of neoplasms. This challenge underscores the urgent need for novel strategies to prevent graft rejection while abrogating toxicity-associated adverse events. AREAS COVERED: We review recent advances in immunoengineering strategies for localized immunomodulation that aim to support allograft function and provide immune tolerance in a safe and effective manner. EXPERT OPINION: Immunoengineering strategies are tailored approaches for achieving immunomodulation of the transplant microenvironment. Biomaterials can be adapted for localized and controlled release of immunomodulatory agents, decreasing the effective dose threshold and frequency of administration. The future of transplant rejection management lies in the shift from systemic to local immunomodulation with suppression of effector and activation of regulatory T cells, to promote immune tolerance.


Assuntos
Tolerância Imunológica , Terapia de Imunossupressão , Transplante de Células , Rejeição de Enxerto/prevenção & controle , Imunomodulação , Imunossupressores/uso terapêutico
5.
Trends Pharmacol Sci ; 43(3): 221-233, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34887129

RESUMO

Beta cell replacement has emerged as an attractive therapeutic alternative to traditional exogenous insulin administration for management of type 1 diabetes (T1D). Beta cells deliver insulin dynamically based on individual glycometabolic requirements, providing glycemic control while significantly reducing patient burden. Although transplantation into the portal circulation is clinically available, poor engraftment, low cell survival, and immune rejection have sparked investigation of alternative strategies for beta cell transplantation. In this review, we focus on current micro- and macroencapsulation technologies for beta cell transplantation and evaluate their advantages and challenges. Specifically, we comment on recent methods to ameliorate graft hypoxia including enhanced vascularization, reduction of pericapsular fibrotic overgrowth (PFO), and oxygen supplementation. We also discuss emerging beta cell-sourcing strategies to overcome donor shortage and provide insight into potential approaches to address outstanding challenges in the field.


Assuntos
Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Diabetes Mellitus Tipo 1/cirurgia , Humanos , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Transplante das Ilhotas Pancreáticas/métodos
7.
Int J Radiat Oncol Biol Phys ; 110(2): 492-506, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32768562

RESUMO

PURPOSE: Mounting evidence demonstrates that combining radiation therapy (RT) with immunotherapy can reduce tumor burden in a subset of patients. However, conventional systemic delivery of immunotherapeutics is often associated with significant adverse effects, which force treatment cessation. The aim of this study was to investigate a minimally invasive therapeutics delivery approach to improve clinical response while attenuating toxicity. METHODS AND MATERIALS: We used a nanofluidic drug-eluting seed (NDES) for sustained intratumoral delivery of combinational antibodies CD40 and PDL1. To enhance immune and tumor response, we combined the NDES intratumoral platform with RT to treat the 4T1 murine model of advanced triple negative breast cancer. We compared the efficacy of NDES against intraperitoneal administration, which mimics conventional systemic treatment. Tumor growth was recorded, and local and systemic immune responses were assessed via imaging mass cytometry and flow cytometry. Livers and lungs were histologically analyzed for evaluation of toxicity and metastasis, respectively. RESULTS: The combination of RT and sustained intratumoral immunotherapy delivery of CD40 and PDL1 via NDES (NDES CD40/PDL1) showed an increase in both local and systemic immune response. In combination with RT, NDES CD40/PDL1 achieved significant tumor burden reduction and liver inflammation mitigation compared with systemic treatment. Importantly, our treatment strategy boosted the abscopal effect toward attenuating lung metastatic burden. CONCLUSIONS: Overall, our study demonstrated superior efficacy of combination treatment with RT and sustained intratumoral immunotherapy via NDES, offering promise for improving therapeutic index and clinical response.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Antineoplásicos/administração & dosagem , Antígenos CD40/imunologia , Imunoterapia/métodos , Nanomedicina Teranóstica/métodos , Neoplasias de Mama Triplo Negativas/terapia , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos/efeitos adversos , Antígeno B7-H1/administração & dosagem , Antígeno B7-H1/imunologia , Antígenos CD40/administração & dosagem , Linfócitos T CD8-Positivos , Linhagem Celular Tumoral , Terapia Combinada/métodos , Implantes de Medicamento , Feminino , Liofilização , Imunoterapia/efeitos adversos , Injeções Intralesionais/métodos , Injeções Intraperitoneais , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Intervalo Livre de Progressão , Hipofracionamento da Dose de Radiação , Distribuição Aleatória , Critérios de Avaliação de Resposta em Tumores Sólidos , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/patologia , Carga Tumoral
8.
Front Cardiovasc Med ; 7: 542485, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33304925

RESUMO

Previously, we reported that post-translational modifications (PTMs) of MAGI1, including S741 phosphorylation and K931 de-SUMOylation, both of which are regulated by p90RSK activation, lead to endothelial cell (EC) activation. However, roles for p90RSK and MAGI1-PTMs in regulating EC permeability remain unclear despite MAGI1 being a junctional molecule. Here, we show that thrombin (Thb)-induced EC permeability, detected by the electric cell-substrate impedance sensing (ECIS) based system, was decreased by overexpression of dominant negative p90RSK or a MAGI1-S741A phosphorylation mutant, but was accelerated by overexpression of p90RSK, siRNA-mediated knockdown of magi1, or the MAGI1-K931R SUMOylation mutant. MAGI1 depletion also increased the mRNA and protein expression of the large tumor suppressor kinases 1 and 2 (LATS1/2), which inhibited YAP/TAZ activity and increased EC permeability. Because the endothelial barrier is a critical mediator of tumor hypoxia, we also evaluated the role of p90RSK activation in tumor vessel leakiness by using a relatively low dose of the p90RSK specific inhibitor, FMK-MEA. FMK-MEA significantly inhibited tumor vessel leakiness at a dose that does not affect morphology and growth of tumor vessels in vivo. These results provide novel insights into crucial roles for p90RSK-mediated MAGI1 PTMs and the Hippo pathway in EC permeability, as well as p90RSK activation in tumor vessel leakiness.

10.
Adv Healthc Mater ; 9(19): e2000670, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32864893

RESUMO

The current standard for cell encapsulation platforms is enveloping cells in semipermeable membranes that physically isolate transplanted cells from the host while allowing for oxygen and nutrient diffusion. However, long-term viability and function of encapsulated cells are compromised by insufficient oxygen and nutrient supply to the graft. To address this need, a strategy to achieve enhanced vascularization of a 3D-printed, polymeric cell encapsulation platform using platelet-rich plasma (PRP) and mesenchymal stem cells (MSCs) is investigated. The study is conducted in rats and, for clinical translation relevance, in nonhuman primates (NHP). Devices filled with PRP, MSCs, or vehicle hydrogel are subcutaneously implanted in rats and NHP and the amount and maturity of penetrating blood vessels assessed via histopathological analysis. In rats, MSCs drive the strongest angiogenic response at early time points, with the highest vessel density and endothelial nitric oxide synthase (eNOS) expression. In NHP, PRP and MSCs result in similar vessel densities but incorporation of PRP ensues higher levels of eNOS expression. Overall, enrichment with PRP and MSCs yields extensive, mature vascularization of subcutaneous cell encapsulation devices. It is postulated that the individual properties of PRP and MSCs can be leveraged in a synergistic approach for maximal vascularization of cell encapsulation platforms.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Plasma Rico em Plaquetas , Animais , Encapsulamento de Células , Hidrogéis , Impressão Tridimensional , Ratos
11.
Biomaterials ; 257: 120232, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32768727

RESUMO

Cell encapsulation is an attractive transplantation strategy to treat endocrine disorders. Transplanted cells offer a dynamic and stimulus-responsive system that secretes therapeutics based on patient need. Despite significant advancements, a challenge in allogeneic cell encapsulation is maintaining sufficient oxygen and nutrient exchange, while providing protection from the host immune system. To this end, we developed a subcutaneously implantable dual-reservoir encapsulation system integrating in situ prevascularization and local immunosuppressant delivery, termed NICHE. NICHE structure is 3D-printed in biocompatible polyamide 2200 and comprises of independent cell and drug reservoirs separated by a nanoporous membrane for sustained local release of immunosuppressant. Here we present the development and characterization of NICHE, as well as efficacy validation for allogeneic cell transplantation in an immunocompetent rat model. We established biocompatibility and mechanical stability of NICHE. Further, NICHE vascularization was achieved with the aid of mesenchymal stem cells. Our study demonstrated sustained local elution of immunosuppressant (CTLA4Ig) into the cell reservoir protected transcutaneously-transplanted allogeneic Leydig cells from host immune destruction during a 31-day study, and reduced systemic drug exposure by 12-fold. In summary, NICHE is the first encapsulation platform achieving both in situ vascularization and immunosuppressant delivery, presenting a viable strategy for allogeneic cell transplantation.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Preparações Farmacêuticas , Animais , Encapsulamento de Células , Imunossupressores , Masculino , Ratos , Transplante Homólogo
12.
JCI Insight ; 4(9)2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31045573

RESUMO

The interplay among signaling events for endothelial cell (EC) senescence, apoptosis, and activation and how these pathological conditions promote atherosclerosis in the area exposed to disturbed flow (d-flow) in concert remain unclear. The aim of this study was to determine whether telomeric repeat-binding factor 2-interacting protein (TERF2IP), a member of the shelterin complex at the telomere, can regulate EC senescence, apoptosis, and activation simultaneously, and if so, by what molecular mechanisms. We found that d-flow induced p90RSK and TERF2IP interaction in a p90RSK kinase activity-dependent manner. An in vitro kinase assay revealed that p90RSK directly phosphorylated TERF2IP at the serine 205 (S205) residue, and d-flow increased TERF2IP S205 phosphorylation as well as EC senescence, apoptosis, and activation by activating p90RSK. TERF2IP phosphorylation was crucial for nuclear export of the TERF2IP-TRF2 complex, which led to EC activation by cytosolic TERF2IP-mediated NF-κB activation and also to senescence and apoptosis of ECs by depleting TRF2 from the nucleus. Lastly, using EC-specific TERF2IP-knockout (TERF2IP-KO) mice, we found that the depletion of TERF2IP inhibited d-flow-induced EC senescence, apoptosis, and activation, as well as atherosclerotic plaque formation. These findings demonstrate that TERF2IP is an important molecular switch that simultaneously accelerates EC senescence, apoptosis, and activation by S205 phosphorylation.


Assuntos
Transporte Ativo do Núcleo Celular/fisiologia , Aterosclerose/metabolismo , Senescência Celular/fisiologia , Células Endoteliais/metabolismo , Proteínas de Ligação a Telômeros/genética , Proteínas de Ligação a Telômeros/metabolismo , Animais , Apoptose , Senescência Celular/efeitos dos fármacos , Dano ao DNA , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Placa Aterosclerótica/metabolismo , Complexo Shelterina , Transdução de Sinais , Telômero , Proteína 2 de Ligação a Repetições Teloméricas/genética , Proteína 2 de Ligação a Repetições Teloméricas/metabolismo , Transcriptoma
13.
J Control Release ; 306: 89-96, 2019 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-31136811

RESUMO

Preexposure prophylaxis (PrEP) with antiretrovirals (ARV) can prevent human immunodeficiency virus (HIV) transmission, but its efficacy is highly dependent on strict patient adherence to daily dosing regimen. Long-acting (LA) ARV formulations or delivery systems that reduce dosing frequency may increase adherence and thus PrEP efficacy. While cabotegravir (CAB) long-acting injectable (CAB LA), an integrase strand transfer inhibitor (INSTI), reduces dosing frequency to bimonthly injections, variable pharmacokinetics (PK) between patients and various adverse reactions necessitate improvement in delivery methods. Here we developed a subcutaneously implantable nanofluidic device for the sustained delivery of CAB formulated with 2-hydroxypropyl-ß-cyclodextrin (ßCAB) and examined the pharmacokinetics (PK) in Sprague-Dawley rats for 3 months in comparison to CAB. Our study demonstrated ßCAB treatment group maintained clinically-relevant plasma CAB concentrations 2 times above the protein-adjusted concentration that inhibits viral replication by 90% (2 × PA-IC90) and drug penetration into tissues relevant to HIV-1 transmission. Further, we successfully fitted plasma CAB concentrations into a PK model (R2 = 0.9999) and determined CAB apparent elimination half-life of 47 days. Overall, our data shows the potential of sustained release of ßCAB via a nanofluidic implant for long-term PrEP delivery, warranting further investigation for efficacy against HIV infections.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina/administração & dosagem , Fármacos Anti-HIV/farmacocinética , Sistemas de Liberação de Medicamentos/instrumentação , Infecções por HIV/prevenção & controle , Profilaxia Pré-Exposição , Piridonas/farmacocinética , Animais , Sistemas de Liberação de Medicamentos/efeitos adversos , Masculino , Piridonas/administração & dosagem , Ratos , Ratos Sprague-Dawley
14.
JCI Insight ; 4(7)2019 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-30944250

RESUMO

The possible association between the membrane-associated guanylate kinase with inverted domain structure-1 (MAGI1) and inflammation has been suggested, but the molecular mechanisms underlying this link, especially during atherogenesis, remain unclear. In endothelial cells (ECs) exposed to disturbed flow (d-flow), p90 ribosomal S6 kinase (p90RSK) bound to MAGI1, causing MAGI1-S741 phosphorylation and sentrin/SUMO-specific protease 2 T368 phosphorylation-mediated MAGI1-K931 deSUMOylation. MAGI1-S741 phosphorylation upregulated EC activation via activating Rap1. MAGI1-K931 deSUMOylation induced both nuclear translocation of p90RSK-MAGI1 and ATF-6-MAGI1 complexes, which accelerated EC activation and apoptosis, respectively. Microarray screening revealed key roles for MAGI1 in the endoplasmic reticulum (ER) stress response. In this context, MAGI1 associated with activating transcription factor 6 (ATF-6). MAGI1 expression was upregulated in ECs and macrophages found in atherosclerotic-prone regions of mouse aortas as well as in the colonic epithelia and ECs of patients with inflammatory bowel disease. Further, reduced MAGI1 expression in Magi1-/+ mice inhibited d-flow-induced atherogenesis. In sum, EC activation and ER stress-mediated apoptosis are regulated in concert by two different types of MAGI1 posttranslational modifications, elucidating attractive drug targets for chronic inflammatory disease, particularly atherosclerosis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Aterosclerose/patologia , Moléculas de Adesão Celular/metabolismo , Estresse do Retículo Endoplasmático , Guanilato Quinases/metabolismo , Doenças Inflamatórias Intestinais/patologia , Fator 6 Ativador da Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Adulto , Animais , Aorta/citologia , Aorta/patologia , Apoptose , Moléculas de Adesão Celular/genética , Células Cultivadas , Colo/citologia , Colo/patologia , Cisteína Endopeptidases/metabolismo , Modelos Animais de Doenças , Células Endoteliais/patologia , Endotélio Vascular/citologia , Endotélio Vascular/patologia , Feminino , Guanilato Quinases/genética , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Fosforilação , Cultura Primária de Células , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Transdução de Sinais , Sumoilação
15.
Adv Healthc Mater ; 8(7): e1701504, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29737043

RESUMO

The advances in biotechnology, biomechanics, and biomaterials can be used to develop organ models that aim to accurately emulate their natural counterparts. Heart disease, one of the leading causes of death in modern society, has attracted particular attention in the field of tissue engineering. To avoid incorrect prognosis of patients suffering from heart disease, or from adverse consequences of classical therapeutic approaches, as well as to address the shortage of heart donors, new solutions are urgently needed. Biotechnological advances in cardiac tissue engineering from a bioreactor perspective, in which recapitulation of functional, biochemical, and physiological characteristics of the cardiac tissue can be used to recreate its natural microenvironment, are reviewed. Detailed examples of functional and preclinical applications of engineered cardiac constructs and the state-of-the-art systems from a bioreactor perspective are provided. Finally, the current trends and future directions of the field for its translation to clinical settings are discussed.


Assuntos
Reatores Biológicos , Engenharia Tecidual , Animais , Doenças Cardiovasculares , Estimulação Elétrica , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Humanos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/transplante , Nanotubos de Carbono/química , Alicerces Teciduais/química
16.
Front Cardiovasc Med ; 5: 125, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30238007

RESUMO

Ponatinib is a multi-targeted third generation tyrosine kinase inhibitor (TKI) used in the treatment of chronic myeloid leukemia (CML) patients harboring the Abelson (Abl)-breakpoint cluster region (Bcr) T315I mutation. In spite of having superb clinical efficacy, ponatinib triggers severe vascular adverse events (VAEs) that significantly limit its therapeutic potential. On vascular endothelial cells (ECs), ponatinib promotes EC dysfunction and apoptosis, and inhibits angiogenesis. Furthermore, ponatinib-mediated anti-angiogenic effect has been suggested to play a partial role in systemic and pulmonary hypertension via inhibition of vascular endothelial growth factor receptor 2 (VEGFR2). Even though ponatinib-associated VAEs are well documented, their etiology remains largely unknown, making it difficult to efficiently counteract treatment-related adversities. Therefore, a better understanding of the mechanisms by which ponatinib mediates VAEs is critical. In cultured human aortic ECs (HAECs) treated with ponatinib, we found an increase in nuclear factor NF-kB/p65 phosphorylation and NF-kB activity, inflammatory gene expression, cell permeability, and cell apoptosis. Mechanistically, ponatinib abolished extracellular signal-regulated kinase 5 (ERK5) transcriptional activity even under activation by its upstream kinase mitogen-activated protein kinase kinase 5α (CA-MEK5α). Ponatinib also diminished expression of ERK5 responsive genes such as Krüppel-like Factor 2/4 (klf2/4) and eNOS. Because ERK5 SUMOylation counteracts its transcriptional activity, we examined the effect of ponatinib on ERK5 SUMOylation, and found that ERK5 SUMOylation is increased by ponatinib. We also found that ponatibib-mediated increased inflammatory gene expression and decreased anti-inflammatory gene expression were reversed when ERK5 SUMOylation was inhibited endogenously or exogenously. Overall, we propose a novel mechanism by which ponatinib up-regulates endothelial ERK5 SUMOylation and shifts ECs to an inflammatory phenotype, disrupting vascular homeostasis.

17.
mBio ; 7(3)2016 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-27247229

RESUMO

UNLABELLED: For over a century, a fundamental objective in infection biology research has been to understand the molecular processes contributing to the origin and perpetuation of epidemics. Divergent hypotheses have emerged concerning the extent to which environmental events or pathogen evolution dominates in these processes. Remarkably few studies bear on this important issue. Based on population pathogenomic analysis of 1,200 Streptococcus pyogenes type emm89 infection isolates, we report that a series of horizontal gene transfer events produced a new pathogenic genotype with increased ability to cause infection, leading to an epidemic wave of disease on at least two continents. In the aggregate, these and other genetic changes substantially remodeled the transcriptomes of the evolved progeny, causing extensive differential expression of virulence genes and altered pathogen-host interaction, including enhanced immune evasion. Our findings delineate the precise molecular genetic changes that occurred and enhance our understanding of the evolutionary processes that contribute to the emergence and persistence of epidemically successful pathogen clones. The data have significant implications for understanding bacterial epidemics and for translational research efforts to blunt their detrimental effects. IMPORTANCE: The confluence of studies of molecular events underlying pathogen strain emergence, evolutionary genetic processes mediating altered virulence, and epidemics is in its infancy. Although understanding these events is necessary to develop new or improved strategies to protect health, surprisingly few studies have addressed this issue, in particular, at the comprehensive population genomic level. Herein we establish that substantial remodeling of the transcriptome of the human-specific pathogen Streptococcus pyogenes by horizontal gene flow and other evolutionary genetic changes is a central factor in precipitating and perpetuating epidemic disease. The data unambiguously show that the key outcome of these molecular events is evolution of a new, more virulent pathogenic genotype. Our findings provide new understanding of epidemic disease.


Assuntos
Proteínas de Bactérias/genética , Epidemias , Interações Hospedeiro-Patógeno , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia , Streptococcus pyogenes/genética , Transcriptoma , Epidemias/prevenção & controle , Evolução Molecular , Transferência Genética Horizontal , Genoma Bacteriano , Genótipo , Humanos , Evasão da Resposta Imune , Polimorfismo de Nucleotídeo Único , Recombinação Genética , Streptococcus pyogenes/imunologia , Streptococcus pyogenes/patogenicidade , Virulência/genética , Fatores de Virulência/genética
18.
Eur J Heart Fail ; 18(2): 169-78, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26749465

RESUMO

AIMS: Ongoing inflammation and endothelial dysfunction occurs within the local microenvironment of heart failure, creating an appropriate scenario for successful use and delivery of nanovectors. This study sought to investigate whether cardiovascular cells associate, internalize, and traffic a nanoplatform called mesoporous silicon vector (MSV), and determine its intravenous accumulation in cardiac tissue in a murine model of heart failure. METHODS AND RESULTS: In vitro cellular uptake and intracellular trafficking of MSVs was examined by scanning electron microscopy, confocal microscopy, time-lapse microscopy, and flow cytometry in cardiac myocytes, fibroblasts, smooth muscle cells, and endothelial cells. The MSVs were internalized within the first hours, and trafficked to perinuclear regions in all the cell lines. Cytotoxicity was investigated by annexin V and cell cycle assays. No significant evidence of toxicity was found. In vivo intravenous cardiac accumulation of MSVs was examined by high content fluorescence and confocal microscopy, with results showing increased accumulation of particles in failing hearts compared with normal hearts. Similar to observations in vitro, MSVs were able to associate, internalize, and traffic to the perinuclear region of cardiomyocytes in vivo. CONCLUSIONS: Results show that MSVs associate, internalize, and traffic in cardiovascular cells without any significant toxicity. Furthermore, MSVs accumulate in failing myocardium after intravenous administration, reaching intracellular regions of the cardiomyocytes. These findings represent a novel avenue to develop nanotechnology-based therapeutics and diagnostics in heart failure.


Assuntos
Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Coração/fisiologia , Coração/fisiopatologia , Miócitos Cardíacos/fisiologia , Nanoestruturas/uso terapêutico , Animais , Materiais Biocompatíveis , Modelos Animais de Doenças , Insuficiência Cardíaca/fisiopatologia , Humanos , Injeções Intravenosas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio , Polímeros , Silício
19.
J Dermatolog Treat ; 26(1): 49-53, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24552591

RESUMO

OBJECTIVE: To assess the efficacy and safety of adalimumab in biologic naïve versus non-biologic naïve psoriasis patients. METHODS: A retrospective multicenter study of patients with moderate-to-severe psoriasis treated uninterruptedly with adalimumab between 6 and 36 months. RESULTS: A total of 100 patients (52 men, 48 women; mean age 45.5 years; 90% plaque-type psoriasis) were included. Previous treatments included biologics in 53 and non-biologic modalities in 47. The mean (SD) start Psoriasis Area and Severity Index (PASI) score was 15.9 (11.1) (range 2-55). The median follow-up was 18 months (interquartile range 10-24 months). Sixteen weeks after the start of treatment, 94% of the patients presented PASI 75 response, 76% PASI 90, and 39% were in complete remission (PASI 100). Similar findings were obtained in the groups of biologic naïve and non-biologic naive patients. At the final visit, around 37% in all groups were in complete remission. At the end of the study, 74 patients continued treatment with adalimumab (43 [91.5%] in the biologic naïve group and 31 [58.5%] in the non-biologic naïve group, p<0.001). CONCLUSION: This study confirms the efficacy and safety of adalimumab for moderate-to-severe psoriasis without differences between biologic naïve and non-naïve patients.


Assuntos
Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Psoríase/tratamento farmacológico , Adalimumab , Adulto , Anti-Inflamatórios/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/patologia , Indução de Remissão , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
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