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1.
Neuron ; 109(5): 788-804.e8, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33497602

RESUMO

Gene Ontology analyses of autism spectrum disorders (ASD) risk genes have repeatedly highlighted synaptic function and transcriptional regulation as key points of convergence. However, these analyses rely on incomplete knowledge of gene function across brain development. Here we leverage Xenopus tropicalis to study in vivo ten genes with the strongest statistical evidence for association with ASD. All genes are expressed in developing telencephalon at time points mapping to human mid-prenatal development, and mutations lead to an increase in the ratio of neural progenitor cells to maturing neurons, supporting previous in silico systems biological findings implicating cortical neurons in ASD vulnerability, but expanding the range of convergent functions to include neurogenesis. Systematic chemical screening identifies that estrogen, via Sonic hedgehog signaling, rescues this convergent phenotype in Xenopus and human models of brain development, suggesting a resilience factor that may mitigate a range of ASD genetic risks.


Assuntos
Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/fisiopatologia , Córtex Cerebral/crescimento & desenvolvimento , Estrogênios/fisiologia , Neurogênese , Animais , Transtorno do Espectro Autista/patologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/patologia , Avaliação Pré-Clínica de Medicamentos , Estrogênios/administração & dosagem , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Masculino , Fatores de Risco , Transdução de Sinais , Xenopus
2.
Int J Hyperthermia ; 37(2): 35-43, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32672118

RESUMO

The blood-brain and blood-tumor barriers represent highly specialized structures responsible for tight regulation of molecular transit into the central nervous system. Under normal circumstances, the relative impermeability of the blood-brain barrier (BBB) protects the brain from circulating toxins and contributes to a brain microenvironment necessary for optimal neuronal function. However, in the context of tumors and other diseases of central nervous system, the BBB and the more recently appreciated blood-tumor barrier (BTB) represent barriers that prevent effective drug delivery. Overcoming both barriers to optimize treatment of central nervous system diseases remains the subject of intense scientific investigation. Although many newer technologies have been developed to overcome these barriers, thermal therapy, which dates back to the 1890 s, has been known to disrupt the BBB since at least the early 1980s. Recently, as a result of several technological advances, laser interstitial thermal therapy (LITT), a method of delivering targeted thermal therapy, has gained widespread use as a surgical technique to ablate brain tumors. In addition, accumulating evidence indicates that laser ablation may also increase local BBB/BTB permeability after treatment. We herein review the structure and function of the BBB and BTB and the impact of thermal injury, including LITT, on barrier function.


Assuntos
Barreira Hematoencefálica , Neoplasias Encefálicas , Hipertermia Induzida , Transporte Biológico , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/terapia , Sistemas de Liberação de Medicamentos , Humanos , Microambiente Tumoral
3.
Adv Biosyst ; 4(3): e1900227, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32293153

RESUMO

One well-studied bacterial factor recognized by the host immune system is lipopolysaccharides (LPS) that stimulate host cells, resulting in cell inflammation. Although photobiomodulation (PBM) therapy demonstrates its potency on anti-inflammatory activity, the complete mechanism of action in the host-bacteria interaction model is still elusive. In addition, many studies were performed regarding a distance between the light source and biological sample (non-contact therapy) that may result in disparate reports on the efficacy of PBM therapy. Thus, it is critical to clearly understand the effect of this approach to maximize efficacy and minimize side effects. Here, a custom-built light-emitting diode (LED) platform that mimics near-contact therapy is developed. The effect and mechanism of PBM therapy on epithelial cells in response to LPS is systematically investigated under various conditions (wavelength, irradiation-time, pulse-frequency). The data show that the irradiation of near-infrared (NIR-LED) significantly improves the viability of inflamed cells. It reveals that NIR-LED inhibits the production of reactive oxygen species by regulating the Nox4-NF-κB pathway. Interestingly, however, high-pulse frequency stimulus causes the collapse of the mitochondrial membrane potential (ΔΨm) of cells, resulting in cell death. These results suggest that the optimized "PBM condition" is critical to assist the healthy immune system of the host against bacterial invasion.


Assuntos
Terapia com Luz de Baixa Intensidade , Modelos Biológicos , Células A549 , Morte Celular/efeitos da radiação , Desenho de Equipamento , Interações Hospedeiro-Patógeno/efeitos da radiação , Humanos , Inflamação/induzido quimicamente , Inflamação/metabolismo , Raios Infravermelhos , Lipopolissacarídeos/efeitos adversos , Impressão Tridimensional , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo
4.
Neurosurgery ; 84(4): 836-843, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30137606

RESUMO

BACKGROUND: Despite the multitude of available treatments, glioblastoma (GBM) remains an aggressive and uniformly fatal tumor. Laser interstitial thermal therapy (LITT) is a novel, minimally invasive treatment that holds promise for treating patients with GBM who are not candidates for traditional open craniotomy. However, due to the recent introduction of LITT into clinical practice, large series that evaluate safety and long-term outcomes after LITT are lacking. OBJECTIVE: To present our institution's series of over 50 GBM patients treated with LITT, with regard to safety, efficacy, and outcomes. METHODS: We performed a retrospective descriptive study of patients with histologically proven GBM who underwent LITT. Data collected included demographics, tumor location and volume, tumor genetic markers, treatment volume, perioperative complications, and long-term follow-up data. RESULTS: We performed 58 LITT treatments for GBM in 54 patients over 5.5 yr. Forty-one were recurrent tumors while 17 were frontline treatments. Forty GBMs were lobar in location, while 18 were in deep structures (thalamus, insula, corpus callosum). Average tumor volume was 12.5 ± 13.4 cm3. Average percentage of tumor treated with the yellow thermal damage threshold (TDT) line (dose equivalent of 43°C for 2 min) was 93.3% ± 10.6%, and with the blue TDT line (dose equivalent of 43°C for 10 min) was 88.0% ± 14.2%. There were 7 perioperative complications (12%) and 2 mortalities (3.4%). Median overall survival after LITT for the total cohort was 11.5 mo, and median progression-free survival 6.6 mo. CONCLUSION: LITT appears to be a safe and effective treatment for GBM in properly selected patients.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Hipertermia Induzida , Imageamento por Ressonância Magnética , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Feminino , Glioblastoma/diagnóstico por imagem , Glioblastoma/mortalidade , Glioblastoma/terapia , Humanos , Hipertermia Induzida/efeitos adversos , Hipertermia Induzida/métodos , Hipertermia Induzida/mortalidade , Hipertermia Induzida/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
5.
J Neurooncol ; 138(1): 105-111, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29374809

RESUMO

Disulfiram has shown promising activity including proteasome inhibitory properties and synergy with temozolomide in preclinical glioblastoma (GBM) models. In a phase I study for newly diagnosed GBM after chemoradiotherapy, we have previously reported our initial dose-escalation results combining disulfiram with adjuvant temozolomide and established the maximum tolerated dose (MTD) as 500 mg per day. Here we report the final results of the phase I study including an additional dose-expansion cohort of disulfiram with concurrent copper. The phase I study consisted of an initial dose-escalation phase of disulfiram 500-1000 mg daily during adjuvant temozolomide, followed by a dose-expansion phase of disulfiram 500 mg daily with copper 2 mg three times daily. Proteasome inhibition was assessed using fluorometric 20S proteasome assay on peripheral blood cell. A total of 18 patients were enrolled: 7 patients received 500 mg disulfiram, 5 patients received 1000 mg disulfiram, and 6 patients received 500 mg disulfiram with copper. Two dose-limiting toxicities occurred with 1000 mg disulfiram. At disulfiram 500 mg with or without copper, only 1 patient (7%) required dose-reduction during the first month of therapy. Addition of copper to disulfiram did not increase toxicity nor proteasome inhibition. The median progression-free survival was 4.5 months (95% CI 0.8-8.2). The median overall survival (OS) was 14.0 months (95% CI 8.3-19.6), and the 2-year OS was 24%. The MTD of disulfiram at 500 mg daily in combination with adjuvant temozolomide was well tolerated by GBM patients, but 1000 mg daily was not. Toxicity and pharmacodynamic effect of disulfiram were similar with or without concurrent copper. The clinical efficacy appeared to be comparable to historical data. Additional clinical trials to combine disulfiram and copper with chemoradiotherapy or to resensitize recurrent GBM to temozolomide are ongoing.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Cobre/uso terapêutico , Dissulfiram/uso terapêutico , Glioblastoma/tratamento farmacológico , Oligoelementos/uso terapêutico , Adjuvantes Imunológicos , Adulto , Idoso , Estudos de Coortes , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Análise de Sobrevida , Temozolomida/uso terapêutico , Adulto Jovem
6.
Eur J Heart Fail ; 18(5): 482-9, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27071916

RESUMO

Composite endpoints are commonly used as the primary measure of efficacy in heart failure clinical trials to assess the overall treatment effect and to increase the efficiency of trials. Clinical trials still must enrol large numbers of patients to accrue a sufficient number of outcome events and have adequate power to draw conclusions about the efficacy and safety of new treatments for heart failure. Additionally, the societal and health system perspectives on heart failure have raised interest in ascertaining the effects of therapy on outcomes such as repeat hospitalization and the patient's burden of disease. Thus, novel methods for using composite endpoints in clinical trials (e.g. clinical status composite endpoints, recurrent event analyses) are being applied in current and planned trials. Endpoints that measure functional status or reflect the patient experience are important but used cautiously because heart failure treatments may improve function yet have adverse effects on mortality. This paper discusses the use of traditional and new composite endpoints, identifies qualities of robust composites, and outlines opportunities for future research.


Assuntos
Insuficiência Cardíaca/terapia , Hospitalização , Mortalidade , Atividades Cotidianas , Causas de Morte , Ensaios Clínicos como Assunto , Humanos , Avaliação de Resultados em Cuidados de Saúde , Qualidade de Vida , Resultado do Tratamento
7.
PLoS One ; 11(2): e0148613, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26910903

RESUMO

BACKGROUND: Poor central nervous system penetration of cytotoxic drugs due to the blood brain barrier (BBB) is a major limiting factor in the treatment of brain tumors. Most recurrent glioblastomas (GBM) occur within the peritumoral region. In this study, we describe a hyperthemic method to induce temporary disruption of the peritumoral BBB that can potentially be used to enhance drug delivery. METHODS: Twenty patients with probable recurrent GBM were enrolled in this study. Fourteen patients were evaluable. MRI-guided laser interstitial thermal therapy was applied to achieve both tumor cytoreduction and disruption of the peritumoral BBB. To determine the degree and timing of peritumoral BBB disruption, dynamic contrast-enhancement brain MRI was used to calculate the vascular transfer constant (Ktrans) in the peritumoral region as direct measures of BBB permeability before and after laser ablation. Serum levels of brain-specific enolase, also known as neuron-specific enolase, were also measured and used as an independent quantification of BBB disruption. RESULTS: In all 14 evaluable patients, Ktrans levels peaked immediately post laser ablation, followed by a gradual decline over the following 4 weeks. Serum BSE concentrations increased shortly after laser ablation and peaked in 1-3 weeks before decreasing to baseline by 6 weeks. CONCLUSIONS: The data from our pilot research support that disruption of the peritumoral BBB was induced by hyperthemia with the peak of high permeability occurring within 1-2 weeks after laser ablation and resolving by 4-6 weeks. This provides a therapeutic window of opportunity during which delivery of BBB-impermeant therapeutic agents may be enhanced. TRIAL REGISTRATION: ClinicalTrials.gov NCT01851733.


Assuntos
Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/cirurgia , Glioblastoma/metabolismo , Glioblastoma/cirurgia , Hipertermia Induzida , Terapia a Laser/métodos , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/enzimologia , Meios de Contraste/metabolismo , Glioblastoma/diagnóstico , Glioblastoma/enzimologia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Fosfopiruvato Hidratase/sangue , Cirurgia Assistida por Computador
8.
Oncotarget ; 6(21): 18282-92, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26286961

RESUMO

Tumor growth is not solely a consequence of autonomous tumor cell properties. Rather, tumor cells act upon and are acted upon by their microenvironment. It is tumor tissue biology that ultimately determines tumor growth. Thus, we developed a compound library screen for agents that could block essential tumor-promoting effects of the glioblastoma (GBM) perivascular stem cell niche (PVN). We modeled the PVN with three-dimensional primary cultures of human brain microvascular endothelial cells in Matrigel. We previously demonstrated stimulated growth of GBM cells in this PVN model and used this to assay PVN function. We screened the Microsource Spectrum Collection library for drugs that specifically blocked PVN function, without any direct effect on GBM cells themselves. Three candidate PVN-disrupting agents, Iridin, Tigogenin and Triacetylresveratrol (TAR), were identified and evaluated in secondary in vitro screens against a panel of primary GBM isolates as well as in two different in vivo intracranial models. Iridin and TAR significantly inhibited intracranial tumor growth and prolonged survival in these mouse models. Together these data identify Iridin and TAR as drugs with novel GBM tissue disrupting effects and validate the importance of preclinical screens designed to address tumor tissue function rather than the mechanisms of autonomous tumor cell growth.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Comunicação Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Extratos Vegetais/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Células Cultivadas , Técnicas de Cocultura , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Feminino , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Camundongos Nus , Fitoterapia , Protaminas/isolamento & purificação , Protaminas/farmacologia , Resveratrol , Bibliotecas de Moléculas Pequenas/isolamento & purificação , Espirostanos/isolamento & purificação , Espirostanos/farmacologia , Estilbenos/química , Estilbenos/isolamento & purificação , Estilbenos/farmacologia , Análise de Sobrevida , Carga Tumoral/efeitos dos fármacos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Cardiovasc Electrophysiol ; 24(3): 297-304, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23110306

RESUMO

INTRODUCTION: Fascicular tachycardia (FT) is an uncommon cause of monomorphic sustained ventricular tachycardia (VT). We describe 6 cases of FT with multiform QRS morphologies. METHODS AND RESULTS: Six of 823 consecutive VT cases were retrospectively analyzed and found attributable to FT with multiform QRS patterns, with 3 cases exhibiting narrow QRS VT as well. All underwent electrophysiology study including fascicular potential mapping, entrainment pacing, and electroanatomic mapping. The first 3 cases describe similar multiform VT patterns with successful ablation in the upper mid septum. Initially, a right bundle branch block (RBBB) VT with superior axis was induced. Radiofrequency catheter ablation (RFCA) targeting the left posterior fascicle (LPF) resulted in a second VT with RBBB inferior axis. RFCA in the upper septum just apical to the LBB potential abolished VT in all cases. Cases 4 and 5 showed RBBB VT with alternating fascicular block compatible with upper septal dependent VT, resulting in bundle branch reentrant VT (BBRT) after ablation of LPF and left anterior fascicle (LAF). Finally, Cases 5 and 6 demonstrated spontaneous shift in QRS morphology during VT, implicating participation of a third fascicle. In Case 6, successful ablation was achieved over the proximal LAF, likely representing insertion of the auxiliary fascicle near the proximal LAF. CONCLUSIONS: Multiform FTs show a reentrant mechanism using multiple fascicular branches. We hypothesize that retrograde conduction over the septal fascicle produces alternate fascicular patterns as well as narrow VT forms. Ablation of the respective fascicle was successful in abolishing FT but does not preclude development of BBRT unless septal fascicle is targeted and ablated.


Assuntos
Fascículo Atrioventricular/cirurgia , Bloqueio de Ramo/diagnóstico , Bloqueio de Ramo/cirurgia , Ablação por Cateter , Técnicas Eletrofisiológicas Cardíacas , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/cirurgia , Adolescente , Adulto , Idoso , Boston , Fascículo Atrioventricular/fisiopatologia , Bloqueio de Ramo/fisiopatologia , Estimulação Cardíaca Artificial , Ablação por Cateter/efeitos adversos , Criança , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , São Francisco , Taquicardia Ventricular/fisiopatologia , Resultado do Tratamento , Adulto Jovem
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