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1.
N Engl J Med ; 390(24): 2252-2263, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38924732

RESUMO

BACKGROUND: Benralizumab is an eosinophil-depleting anti-interleukin-5 receptor α monoclonal antibody. The efficacy and safety of benralizumab in patients with eosinophilic esophagitis are unclear. METHODS: In a phase 3, multicenter, double-blind, randomized, placebo-controlled trial, we assigned patients 12 to 65 years of age with symptomatic and histologically active eosinophilic esophagitis in a 1:1 ratio to receive subcutaneous benralizumab (30 mg) or placebo every 4 weeks. The two primary efficacy end points were histologic response (≤6 eosinophils per high-power field) and the change from baseline in the score on the Dysphagia Symptom Questionnaire (DSQ; range, 0 to 84, with higher scores indicating more frequent or severe dysphagia) at week 24. RESULTS: A total of 211 patients underwent randomization: 104 were assigned to receive benralizumab, and 107 were assigned to receive placebo. At week 24, more patients had a histologic response with benralizumab than with placebo (87.4% vs. 6.5%; difference, 80.8 percentage points; 95% confidence interval [CI], 72.9 to 88.8; P<0.001). However, the change from baseline in the DSQ score did not differ significantly between the two groups (difference in least-squares means, 3.0 points; 95% CI, -1.4 to 7.4; P = 0.18). There was no substantial between-group difference in the change from baseline in the Eosinophilic Esophagitis Endoscopic Reference Score, which reflects endoscopic abnormalities. Adverse events were reported in 64.1% of the patients in the benralizumab group and in 61.7% of those in the placebo group. No patients discontinued the trial because of adverse events. CONCLUSIONS: In this trial involving patients 12 to 65 years of age with eosinophilic esophagitis, a histologic response (≤6 eosinophils per high-power field) occurred in significantly more patients in the benralizumab group than in the placebo group. However, treatment with benralizumab did not result in fewer or less severe dysphagia symptoms than placebo. (Funded by AstraZeneca; MESSINA ClinicalTrials.gov number, NCT04543409.).


Assuntos
Anticorpos Monoclonais Humanizados , Esofagite Eosinofílica , Eosinófilos , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/tratamento farmacológico , Método Duplo-Cego , Esofagite Eosinofílica/tratamento farmacológico , Esofagite Eosinofílica/imunologia , Subunidade alfa de Receptor de Interleucina-5/antagonistas & inibidores , Contagem de Leucócitos
2.
Synapse ; 78(4): e22292, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38813758

RESUMO

N-methyl-d-aspartate receptors (NMDARs) at hippocampal excitatory synapses undergo a late postnatal shift in subunit composition, from an initial prevalence of GluN2B subunit incorporation to a later predominance of GluN2A. This GluN2B to GluN2A shift alters NMDAR calcium conductance dynamics and intracellular molecular signaling that are individually regulated by distinct GluN2 signaling domains and temporally align with developmental alterations in dendritic and synaptic plasticity. However, the impacts of individual GluN2B to GluN2A signaling domains on neuronal development remain unknown. Ionotropic and intracellular signaling domains of GluN2 subunits were separated by creating chimeric GluN2 subunits that were expressed in two transgenic mouse lines. Western blot and immunoprecipitation revealed that roughly one third of native synaptic NMDARs were replaced by transformed NMDARs without altering total synaptic NMDAR content. Schaffer collateral synaptic strength was transiently increased in acutely prepared hippocampal slices at just over 3 weeks of age in animals overexpressing the GluN2B carboxy terminus. Long-term potentiation (LTP) induction following lower frequency stimulation was regulated by GluN2 ionotropic signaling domains in an age-dependent manner and LTP maintenance was enhanced by overexpression of the GluN2B CTD in mature animals. After higher frequency stimulation, the induction and maintenance of LTP were increased in young adult animals overexpressing the GluN2B ionotropic signaling domains but reduced in juveniles just over 3 weeks of age. Confocal imaging of green fluorescent protein (GFP)- labeled CA1 pyramidal neurons revealed no alterations in dendritic morphology or spine density in mice expressing chimeric GluN2 subunits. These results illustrate how individual GluN2 subunit signaling domains do or do not control physiological and morphological development of hippocampal excitatory neurons and better clarify the neurobiological factors that govern hippocampal maturation. SIGNIFICANCE STATEMENT: A developmental reduction in the magnitude of hippocampal long-term synaptic potentiation (LTP) and a concomitant improvement in spatial maze performance coincide with greater incorporation of GluN2A subunits into synaptic NMDARs. Corroborating our prior discovery that overexpression of GluN2A-type ionotropic signaling domains enables context-based navigation in immature mice, GluN2A-type ionotropic signaling domain overexpression reduces LTP induction threshold and magnitude in immature mice. Also, we previously found that GluN2B carboxy terminal domain (CTD) overexpression enhances long-term spatial memory in mature mice and now report that the GluN2B CTD is associated with greater amplitude of LTP after induction in mature mice. Thus, the late postnatal maturation of context encoding likely relies on a shift toward GluN2A-type ionotropic signaling and a reduction in the threshold to induce LTP while memory consolidation and LTP maintenance are regulated by GluN2B subunit CTD signaling.


Assuntos
Dendritos , Hipocampo , Camundongos Transgênicos , Plasticidade Neuronal , Receptores de N-Metil-D-Aspartato , Animais , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores de N-Metil-D-Aspartato/genética , Hipocampo/metabolismo , Hipocampo/crescimento & desenvolvimento , Hipocampo/fisiologia , Dendritos/fisiologia , Dendritos/metabolismo , Camundongos , Plasticidade Neuronal/fisiologia , Potenciação de Longa Duração/fisiologia , Transmissão Sináptica/fisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Transdução de Sinais/fisiologia , Camundongos Endogâmicos C57BL , Masculino
3.
Eur Respir J ; 58(6)2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34112734

RESUMO

BACKGROUND: Greater precision in asthma exacerbation risk prediction may improve outcomes. We sought to identify clinical characteristics and biomarkers associated with elevated exacerbation risk in patients with severe, uncontrolled asthma. METHODS: Data were pooled from seven similarly designed phase II and III randomised controlled clinical trials of biologic therapies for the treatment of severe, uncontrolled asthma that enrolled comparable patient populations. Annualised asthma exacerbation rates (AAERs) for patients randomised to placebo were assessed by baseline clinical characteristics, and by biomarker concentrations at baseline and over the study duration. RESULTS: The AAER for the 2016 patients in the combined placebo group was 0.91 (95% CI 0.84‒0.98). Baseline characteristics associated with greater AAER were frequent or severe exacerbations within the prior 12 months, nasal polyposis, maintenance oral corticosteroid use, Asian race and Asian or Western European region. AAER increased with baseline blood eosinophil counts and exhaled nitric oxide fraction (F ENO) concentration, with the greatest AAER occurring for patients with eosinophils ≥300 cells·µL-1 and F ENO ≥50 ppb. No relationship was observed between baseline serum IgE concentration and AAER. Combining type 2 inflammation criteria for eosinophils and F ENO had greater prognostic value than either biomarker alone. Persistent eosinophil and F ENO elevations throughout the study period were associated with greater AAER. CONCLUSIONS: Exacerbation history, maintenance corticosteroid use, nasal polyposis, Asian race, geographic region, and elevations in blood eosinophil counts and F ENO concentrations (particularly when combined and/or persistently achieving type 2 inflammation criteria) were associated with increased exacerbation risk in patients with severe, uncontrolled asthma.


Assuntos
Antiasmáticos , Asma , Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Biomarcadores , Método Duplo-Cego , Eosinófilos , Humanos
4.
Learn Mem ; 25(6): 264-272, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29764972

RESUMO

N-methyl-d-aspartate receptors (NMDARs) at excitatory synapses are central to activity-dependent synaptic plasticity and learning and memory. NMDARs act as ionotropic and metabotropic receptors by elevating postsynaptic calcium concentrations and by direct intracellular protein signaling. In the forebrain, these properties are controlled largely by the auxiliary GluN2 subunits, GluN2A and GluN2B. While calcium conductance through NMDAR channels and intracellular protein signaling make separate contributions to synaptic plasticity, it is not known if these properties individually influence learning and memory. To address this issue, we created chimeric GluN2 subunits containing the amino-terminal domain and transmembrane domains from GluN2A or GluN2B fused to the carboxy-terminal domain of GluN2B (termed ABc) or GluN2A ATD (termed BAc), respectively, and expressed these mutated GluN2 subunits in transgenic mice. Expression was confirmed at the mRNA level and protein subunit translation and translocation into dendrites were observed in forebrain neurons. In the spatial version of the Morris water maze, BAc mice displayed signs of a learning deficit. In contrast, ABc animals performed similarly to wild-types during training, but showed a more direct approach to the goal location during a long-term memory test. There was no effect of ABc or BAc expression in a nonspatial water escape task. Since background expression is predominantly GluN2A in mature animals, the results suggest that spatial learning is more sensitive to manipulations of the amino-terminal domain and transmembrane domains (calcium conductance) and long-term memory is regulated more by the carboxy-terminal domain (intracellular protein signaling).


Assuntos
Aprendizagem em Labirinto/fisiologia , Memória de Longo Prazo/fisiologia , Receptores de N-Metil-D-Aspartato/metabolismo , Sequência de Aminoácidos , Animais , Deficiências da Aprendizagem/metabolismo , Transtornos da Memória/metabolismo , Camundongos Transgênicos , Neurônios/metabolismo , Prosencéfalo/metabolismo , Domínios Proteicos , RNA Mensageiro/metabolismo , Receptores de N-Metil-D-Aspartato/genética , Comportamento Espacial/fisiologia
5.
Stem Cells ; 34(12): 2916-2929, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27501845

RESUMO

Histone deacetylase (HDAC) regulation is an essential process in myogenic differentiation. Inhibitors targeting the activity of specific HDAC family members have been shown to enhance the cardiogenic differentiation capacity of discrete progenitor cell types; a key property of donor cell populations contributing to their afforded benefits in cardiac cell therapy applications. The influence of HDAC inhibition on cardiac-derived mesenchymal stromal cell (CMC) transdifferentiation or the role of specific HDAC family members in dictating cardiovascular cell lineage specification has not been investigated. In the current study, the consequences of HDAC inhibition on patient-derived CMC proliferation, cardiogenic program activation, and cardiovascular differentiation/cell lineage specification were investigated using pharmacologic and genetic targeting approaches. Here, CMCs exposed to the pan-HDAC inhibitor sodium butyrate exhibited induction of a cardiogenic transcriptional program and heightened expression of myocyte and endothelial lineage-specific markers when coaxed to differentiate in vitro. Further, shRNA knockdown screens revealed CMCs depleted of HDAC1 to promote the induction of a cardiogenic transcriptional program characterized by enhanced expression of cardiomyogenic- and vasculogenic-specific markers, a finding which depended on and correlated with enhanced acetylation and stabilization of p53. Cardiogenic gene activation and elevated p53 expression levels observed in HDAC1-depleted CMCs were associated with improved aptitude to assume a cardiomyogenic/vasculogenic cell-like fate in vitro. These results suggest that HDAC1 depletion-induced p53 expression alters CMC cell fate decisions and identify HDAC1 as a potential exploitable target to facilitate CMC-mediated myocardial repair in ischemic cardiomyopathy. Stem Cells 2016;34:2916-2929.


Assuntos
Epigênese Genética , Histona Desacetilase 1/metabolismo , Células-Tronco Mesenquimais/metabolismo , Miócitos Cardíacos/metabolismo , Transcrição Gênica , Proteína Supressora de Tumor p53/metabolismo , Acetilação , Biomarcadores/metabolismo , Ácido Butírico/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem da Célula/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Células HEK293 , Inibidores de Histona Desacetilases/farmacologia , Histonas/metabolismo , Humanos , Imunofenotipagem , Células-Tronco Mesenquimais/citologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Transcrição Gênica/efeitos dos fármacos
6.
Circ Res ; 116(7): 1216-30, 2015 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-25814683

RESUMO

Although numerous preclinical investigations have consistently demonstrated salubrious effects of c-kit(pos) cardiac cells administered after myocardial infarction, the mechanism of action remains highly controversial. We and others have found little or no evidence that these cells differentiate into mature functional cardiomyocytes, suggesting paracrine effects. In this review, we propose a new paradigm predicated on a comprehensive analysis of the literature, including studies of cardiac development; we have (facetiously) dubbed this conceptual construct "string theory" of c-kit(pos) cardiac cells because it reconciles multifarious and sometimes apparently discrepant results. There is strong evidence that, during development, the c-kit receptor is expressed in different pools of cardiac progenitors (some capable of robust cardiomyogenesis and others with little or no contribution to myocytes). Accordingly, c-kit positivity, in itself, does not define the embryonic origins, lineage capabilities, or differentiation capacities of specific cardiac progenitors. C-kit(pos) cells derived from the first heart field exhibit cardiomyogenic potential during development, but these cells are likely depleted shortly before or after birth. The residual c-kit(pos) cells found in the adult heart are probably of proepicardial origin, possess a mesenchymal phenotype (resembling bone marrow mesenchymal stem/stromal cells), and are capable of contributing significantly only to nonmyocytic lineages (fibroblasts, smooth muscle cells, and endothelial cells). If these 2 populations (first heart field and proepicardium) express different levels of c-kit, the cardiomyogenic potential of first heart field progenitors might be reconciled with recent results of c-kit(pos) cell lineage tracing studies. The concept that c-kit expression in the adult heart identifies epicardium-derived, noncardiomyogenic precursors with a mesenchymal phenotype helps to explain the beneficial effects of c-kit(pos) cell administration to ischemically damaged hearts despite the observed paucity of cardiomyogenic differentiation of these cells.


Assuntos
Linhagem da Célula , Modelos Cardiovasculares , Infarto do Miocárdio/terapia , Miócitos Cardíacos/transplante , Proteínas Proto-Oncogênicas c-kit , Túnica Adventícia/citologia , Vasos Sanguíneos/citologia , Vasos Sanguíneos/embriologia , Diferenciação Celular , Ensaios Clínicos Fase I como Assunto , Citocinas/fisiologia , Endocárdio/citologia , Endocárdio/embriologia , Transição Epitelial-Mesenquimal , Sobrevivência de Enxerto , Coração/embriologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Músculo Liso/citologia , Miócitos Cardíacos/química , Comunicação Parácrina , Pericárdio/citologia , Pericárdio/embriologia , Células-Tronco/química , Células-Tronco/classificação , Células-Tronco/citologia , Transplante Autólogo
7.
Basic Res Cardiol ; 110(5): 503, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26150250

RESUMO

It is commonly thought that the optimal method for intracoronary administration of cells is to stop coronary flow during cell infusion, in order to prolong cell/vascular wall contact, enhance adhesion, and promote extravasation of cells into the interstitial space. However, occlusion of a coronary artery with a balloon involves serious risks of vascular damage and/or dissection, particularly in non-stented segments such as those commonly found in patients with heart failure. It remains unknown whether the use of the stop-flow technique results in improved donor cell retention. Acute myocardial infarction was produced in 14 pigs. One to two months later, pigs received 10 million indium-111 oxyquinoline (oxine)-labeled c-kit(pos) human cardiac stem cells (hCSCs) via intracoronary infusion with (n = 7) or without (n = 7) balloon inflation. Pigs received cyclosporine to prevent acute graft rejection. Animals were euthanized 24 h later and hearts harvested for radioactivity measurements. With the stop-flow technique, the retention of hCSCs at 24 h was 5.41 ± 0.80 % of the injected dose (n = 7), compared with 4.87 ± 0.62 % without coronary occlusion (n = 7), (P = 0.60). When cells are delivered intracoronarily in a clinically relevant porcine model of chronic ischemic cardiomyopathy, the use of the stop-flow technique does not result in greater myocardial cell retention at 24 h compared with non-occlusive infusion. These results have practical implications for the design of cell therapy trials. Our observations suggest that the increased risk of complications secondary to coronary manipulation and occlusion is not warranted.


Assuntos
Isquemia Miocárdica/cirurgia , Miócitos Cardíacos/transplante , Transplante de Células-Tronco/métodos , Animais , Separação Celular , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Humanos , Proteínas Proto-Oncogênicas c-kit , Sus scrofa
8.
Environ Health Prev Med ; 20(5): 338-46, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26068785

RESUMO

OBJECTIVES: Mennonites reside in clusters, do not use modern sewage systems and consume water from non-municipal sources. The purpose of this study is to assess risk of Escherichia coli exposure via consumption of non-municipal waters in Mennonite versus non-Mennonite rural households. METHODS: Results were reviewed for non-municipal water samples collected by the local health department from Mennonite and non-Mennonite lifestyle households from 1998 through 2012. Water contamination was examined with the help of two study variables: water quality (potable, polluted) and gastrointestinal (GI) health risk (none, low, high). These variables were analyzed for association with lifestyle (Mennonite, non-Mennonite) and season (fall, winter, spring, summer) of sample collection. Data were split into two periods to adjust for the ceiling effect of laboratory instrument. RESULTS: From the entire cohort, 82 % samples were polluted and 46 % samples contained E. coli, which is consistent with high GI health risk. In recent years (2009 through 2012), the presence of total coliforms was higher in non-Mennonites (39 %, P = 0.018) and presence of E. coli was higher in Mennonites (P = 0.012). Most polluted samples were collected during summer (45 %, P = 0.019) and had high GI health risk (51 %, P = 0.008) as compared to other seasons. CONCLUSIONS: Majority of non-municipal waters in this region are polluted, consuming those poses a high GI health risk and contamination is prevalent in all households consuming these waters. An association of E. coli exposure with the Mennonite lifestyle was limited to recent years. Seasons with high heat index and increased surface runoffs were the riskiest to consume non-municipal waters.


Assuntos
Água Potável/microbiologia , Enterobacteriaceae/isolamento & purificação , Estilo de Vida , População Rural , Qualidade da Água , Humanos , Kentucky , Protestantismo , Estações do Ano
9.
Polymers (Basel) ; 16(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38931972

RESUMO

Today, 98% of all plastics are fossil-based and non-biodegradable, and globally, only 9% are recycled. Microplastic and nanoplastic pollution is just beginning to be understood. As the global demand for sustainable alternatives to conventional plastics continues to rise, biobased and biodegradable plastics have emerged as a promising solution. This review article delves into the pivotal concept of carbon recycling as a pathway towards achieving a zero-waste future through the production and utilization of high-value bioplastics. The review comprehensively explores the current state of bioplastics (biobased and/or biodegradable materials), emphasizing the importance of carbon-neutral and circular approaches in their lifecycle. Today, bioplastics are chiefly used in low-value applications, such as packaging and single-use items. This article sheds light on value-added applications, like longer-lasting components and products, and demanding properties, for which bioplastics are increasingly being deployed. Based on the waste hierarchy paradigm-reduce, reuse, recycle-different use cases and end-of-life scenarios for materials will be described, including technological options for recycling, from mechanical to chemical methods. A special emphasis on common bioplastics-TPS, PLA, PHAs-as well as a discussion of composites, is provided. While it is acknowledged that the current plastics (waste) crisis stems largely from mismanagement, it needs to be stated that a radical solution must come from the core material side, including the intrinsic properties of the polymers and their formulations. The manner in which the cascaded use of bioplastics, labeling, legislation, recycling technologies, and consumer awareness can contribute to a zero-waste future for plastics is the core topics of this article.

10.
bioRxiv ; 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37873200

RESUMO

Glioblastomas (GBMs) are highly aggressive, infiltrative, and heterogeneous brain tumors driven by complex driver mutations and glioma stem cells (GSCs). The neurodevelopmental transcription factors ASCL1 and OLIG2 are co-expressed in GBMs, but their role in regulating the heterogeneity and hierarchy of GBM tumor cells is unclear. Here, we show that oncogenic driver mutations lead to dysregulation of ASCL1 and OLIG2, which function redundantly to initiate brain tumor formation in a mouse model of GBM. Subsequently, the dynamic levels and reciprocal binding of ASCL1 and OLIG2 to each other and to downstream target genes then determine the cell types and degree of migration of tumor cells. Single-cell RNA sequencing (scRNA-seq) reveals that a high level of ASCL1 is key in defining GSCs by upregulating a collection of ribosomal protein, mitochondrial, neural stem cell (NSC), and cancer metastasis genes - all essential for sustaining the high proliferation, migration, and therapeutic resistance of GSCs.

12.
Heart Rhythm O2 ; 2(1): 73-79, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34113907

RESUMO

BACKGROUND: Studies have demonstrated magnetic resonance imaging (MRI) safety in the presence of MRI-conditional permanent pacemakers (PPM). However, since patients' care may require serial MRIs, it is necessary to evaluate device safety and performance after multiple scans. OBJECTIVES: We evaluated safety and performance of MRI-conditional PPMs after serial MRIs over various anatomic regions performed during a multicenter, prospective, single-arm study (ProMRI). METHODS: ProMRI was a multiphase observational study designed to evaluate PPM performance after MRI scans. Our study evaluated PPM function in a cohort of patients who underwent multiple 1.5-T MRI scans. Selected patients underwent separate head, chest, and lumbar spine MRIs. Pacing capture threshold (PCT), lead impedance (LI), sensing amplitude, and battery capacity were collected before and after scanning. Freedom from serious adverse device effects (SADE) through 1 month post MRI served as a primary endpoint. Changes in PPM function parameters, including threshold success rate and sensing attenuation, were analyzed for statistical significance and clinical relevance. RESULTS: In 81 patients no adverse events or SADE occurred. Statistically significant changes in ventricular PCT (0.034 ± 0.15 V) immediately after, ventricular LI immediately after (-18.7 ± 44.2 Ω) and 1 month post phase B (-19.8 ± 44.9 Ω), and atrial sensing attenuation immediately after (-0.27 ± 0.92 mV) and 1 month post phase B (-0.22 ± 0.92 mV) were noted. However, these changes were not clinically relevant in degree. CONCLUSION: These results demonstrate the safety and performance of the ProMRI PPM in patients undergoing 3 serial MRIs over various anatomic regions.

13.
Neuroscience ; 396: 138-153, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30471357

RESUMO

N-methyl-d-aspartate receptors (NMDARs) are glutamatergic receptors that take part in excitatory synaptic transmission and drive functional and structural neuronal plasticity, including activity-dependent changes in dendritic morphology. Forebrain NMDARs contribute to neuronal plasticity in at least two ways: through calcium-mediated processes or via direct intracellular postsynaptic signaling. Both properties are regulated by the GluN2 subunits. However, the separate contributions of these properties to the regulation of dendritic morphology are unknown. We created transgenic mice that express chimeric GluN2 subunits and examined the impact on pyramidal cell dendritic morphology in hippocampal region CA1. Golgi-Cox impregnation and transgenic expression of green fluorescent protein were employed to visualize dendritic arbors. In adult mice with a predominantly native GluN2A background, overexpression of the GluN2B carboxy terminus increased the total path of the dendritic arbor without affecting branch number or tortuosity. Overexpressing the amino terminus and transmembrane domains of GluN2B had little effect. It may be inferred from these results that NMDAR-dependent intracellular signaling regulates dendritic morphology of hippocampal pyramidal cells more so than calcium conductance dynamics. The findings add to the understanding of NMDAR-mediated signaling in hippocampal neurons and support re-investigation of the molecular underpinnings of NMDAR involvement in postnatal dendrite maturation.


Assuntos
Região CA1 Hipocampal/citologia , Forma Celular , Dendritos/ultraestrutura , Células Piramidais/citologia , Receptores de N-Metil-D-Aspartato/genética , Animais , Feminino , Genótipo , Masculino , Camundongos , Camundongos Transgênicos , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores de N-Metil-D-Aspartato/fisiologia , Regulação para Cima
14.
Tex Heart Inst J ; 45(4): 260-263, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30374242

RESUMO

Proteasome inhibitors such as bortezomib and carfilzomib have been used effectively to treat patients who have certain hematologic malignancies. Proteasome activity is elevated in the heart, and potent inhibition results in accumulation of misfolded intracellular protein aggregates and apoptosis. Heart failure, conduction disturbances, and premature atherosclerosis have been associated with bortezomib therapy. We describe the case of a 49-year-old man who was taking bortezomib for graft-versus-host disease, when he developed cardiac tamponade and needed emergency pericardiocentesis. At that time, there was no evidence of graft-versus-host disease. To our knowledge, this is the first time that a pericardial effusion without underlying cardiac dysfunction has been reported in relation to bortezomib therapy. The diagnosis of pericardial effusion during bortezomib therapy, the absence of other causative agents-including graft-versus-host disease-and no recurrence of pericardial effusion after discontinuing bortezomib therapy suggest that bortezomib caused our patient's tamponade.


Assuntos
Bortezomib/efeitos adversos , Tamponamento Cardíaco/induzido quimicamente , Doença Enxerto-Hospedeiro/tratamento farmacológico , Pericardiocentese/métodos , Cirurgia Assistida por Computador/métodos , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Bortezomib/uso terapêutico , Tamponamento Cardíaco/diagnóstico , Tamponamento Cardíaco/cirurgia , Ecocardiografia Doppler , Fluoroscopia , Seguimentos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Masculino , Pessoa de Meia-Idade
15.
J Am Heart Assoc ; 6(7)2017 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-28679560

RESUMO

BACKGROUND: Cardiac mesenchymal cell (CMC) administration improves cardiac function in animal models of heart failure. Although the precise mechanisms remain unclear, transdifferentiation and paracrine signaling are suggested to underlie their cardiac reparative effects. We have shown that histone deacetylase 1 (HDAC1) inhibition enhances CMC cardiomyogenic lineage commitment. Here, we investigated the impact of HDAC1 on CMC cytokine secretion and associated paracrine-mediated activities on endothelial cell function. METHODS AND RESULTS: CMCs were transduced with shRNA constructs targeting HDAC1 (shHDAC1) or nontarget (shNT) control. Cytokine arrays were used to assess the expression of secreted proteins in conditioned medium (CM) from shHDAC1 or shNT-transduced CMCs. In vitro functional assays for cell proliferation, protection from oxidative stress, cell migration, and tube formation were performed on human endothelial cells incubated with CM from the various treatment conditions. CM from shHDAC1-transduced CMCs contained more cytokines involved in cell growth/differentiation and more efficiently promoted endothelial cell proliferation and tube formation compared with CM from shNT. After evaluating key cytokines previously implicated in cell-therapy-mediated cardiac repair, we found that basic fibroblast growth factor was significantly upregulated in shHDAC1-transduced CMCs. Furthermore, shRNA-mediated knockdown of basic fibroblast growth factor in HDAC1-depleted CMCs inhibited the effects of shHDAC1 CM in promoting endothelial proliferation and tube formation-indicating that HDAC1 depletion activates CMC proangiogenic paracrine signaling in a basic fibroblast growth factor-dependent manner. CONCLUSIONS: These results reveal a hitherto unknown role for HDAC1 in the modulation of CMC cytokine secretion and implicate the targeted inhibition of HDAC1 in CMCs as a means to enhance paracrine-mediated neovascularization in cardiac cell therapy applications.


Assuntos
Proteínas Angiogênicas/biossíntese , Fator 2 de Crescimento de Fibroblastos/biossíntese , Coração , Histona Desacetilase 1/deficiência , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células-Tronco Mesenquimais/enzimologia , Miócitos Cardíacos/enzimologia , Neovascularização Fisiológica , Comunicação Parácrina , Proteínas Angiogênicas/metabolismo , Diferenciação Celular , Linhagem da Célula , Movimento Celular , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados/metabolismo , Citocinas/metabolismo , Repressão Enzimática , Fator 2 de Crescimento de Fibroblastos/metabolismo , Coração/metabolismo , Histona Desacetilase 1/genética , Humanos , Células-Tronco Mesenquimais/metabolismo , Miócitos Cardíacos/metabolismo , Estresse Oxidativo , Transdução de Sinais , Fatores de Tempo , Transdução Genética , Transfecção
16.
Int J Cardiol Heart Vasc ; 13: 6-13, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28616553

RESUMO

OBJECTIVE: This was a prospective, single-center study evaluating the efficacy and cost-effectiveness of early ambulation (within 30 min) following femoral artery closure with the ProGlide® suture-mediated vascular closure device (PD) in patients undergoing diagnostic cardiac catheterization compared with manual compression. BACKGROUND: It is unclear whether early ambulation with ProGlide is safe or is associated with patient satisfaction and cost savings as compared with manual compression (MC). METHODS AND RESULTS: Inclusion criteria were met in 170 patients (85 PD and 85 MC patients). Patients ambulated 20 ft. within 30 min (PD) or after the requisite 4 h recumbent time (MC) if feasible. Primary endpoint was time-to-ambulation (TTA) following device closure. We also directly compared the safety of closure, times-to-hemostasis (TTH), -ambulation (TTA) and -discharge (TTD) with MC and, using a fully allocated cost model, performed cost analysis for both strategies. Multivariate analysis was used to determine predictors of patient satisfaction. The primary endpoint of safe, early ambulation was achieved following closure (mean of 27.1 ± 14.9 min; 95% confidence interval [CI] 25.2-30.2). Predictors of patient satisfaction in the PD group were absence of pain during closure, decreased TTA, and drastic reductions in TTD; the latter contributed indirectly to significant cost savings in the PD group (1250.3 ± 146.4 vs. 2248.1 ± 910.2 dollars, respectively; P < 0.001) and incremental cost savings by strategy also favored closure over MC ($84,807). CONCLUSIONS: ProGlide is safe and effective for femoral artery closure in patients who ambulate within 30 min after cardiac catheterization; translating into improved patient satisfaction and substantial cost savings.

17.
PLoS One ; 10(10): e0140798, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26474484

RESUMO

A recent phase I clinical trial (SCIPIO) has shown that autologous c-kit+ cardiac progenitor cells (CPCs) improve cardiac function and quality of life when transplanted into patients with ischemic heart disease. Although c-kit is widely used as a marker of resident CPCs, its role in the regulation of the cellular characteristics of CPCs remains unknown. We hypothesized that c-kit plays a role in the survival, growth, and migration of CPCs. To test this hypothesis, human CPCs were grown under stress conditions in the presence or absence of SCF, and the effects of SCF-mediated activation of c-kit on CPC survival/growth and migration were measured. SCF treatment led to a significant increase in cell survival and a reduction in cell death under serum depletion conditions. In addition, SCF significantly promoted CPC migration in vitro. Furthermore, the pro-survival and pro-migratory effects of SCF were augmented by c-kit overexpression and abrogated by c-kit inhibition with imatinib. Mechanistically, c-kit activation in CPCs led to activation of the PI3K and the MAPK pathways. With the use of specific inhibitors, we confirmed that the SCF/c-kit-dependent survival and chemotaxis of CPCs are dependent on both pathways. Taken together, our findings suggest that c-kit promotes the survival/growth and migration of human CPCs cultured ex vivo via the activation of PI3K and MAPK pathways. These results imply that the efficiency of CPC homing to the injury site as well as their survival after transplantation may be improved by modulating the activity of c-kit.


Assuntos
Quimiotaxia , Sistema de Sinalização das MAP Quinases , Miocárdio/citologia , Proteínas Proto-Oncogênicas c-kit/metabolismo , Células-Tronco/citologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quimiotaxia/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Células-Tronco/farmacologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
18.
Circ Heart Fail ; 8(4): 757-65, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25995227

RESUMO

BACKGROUND: Although c-kit(pos) cardiac stem cells (CSCs) preserve left ventricular (LV) function and structure after myocardial infarction, CSC doses have been chosen arbitrarily, and the dose-effect relationship is unknown. METHODS AND RESULTS: Rats underwent a 90-minute coronary occlusion followed by 35 days of reperfusion. Vehicle or CSCs at 5 escalating doses (0.3×10(6), 0.75×10(6), 1.5×10(6), 3.0×10(6), and 6.0×10(6) cells/heart) were given intracoronarily 4 h after reperfusion. The lowest dose (0.3×10(6)) had no effect on LV function and morphology, whereas 0.75, 1.5, and 3.0×10(6) significantly improved regional and global LV function (echocardiography and hemodynamic studies). These 3 doses had similar effects on echocardiographic parameters (infarct wall thickening fraction, LV end-systolic and end-diastolic volumes, LV ejection fraction) and hemodynamic variables (LV end-diastolic pressure, LV dP/dtmax, preload adjusted maximal power, end-systolic elastance, preload recruitable stroke work) and produced similar reductions in apoptosis, scar size, infarct wall thinning, and LV expansion index and similar increases in viable myocardium in the risk region (morphometry). Infusion of 6.0×10(6) CSCs markedly increased postprocedural mortality. Green fluorescent protein and 5-bromo-2'-deoxyuridine staining indicated that persistence of donor cells and formation of new myocytes were negligible with all doses. CONCLUSIONS: Surprisingly, in this rat model of acute myocardial infarction, the dose-response relationship for intracoronary CSCs is flat. A minimal dose between 0.3 and 0.75×10(6) is necessary for efficacy; above this threshold, a 4-fold increase in cell number does not produce greater improvement in LV function or structure. Further increases in cell dose are harmful.


Assuntos
Infarto do Miocárdio/cirurgia , Miocárdio/patologia , Miócitos Cardíacos/transplante , Regeneração , Transplante de Células-Tronco , Função Ventricular Esquerda , Animais , Apoptose , Biomarcadores/metabolismo , Capilares/fisiopatologia , Débito Cardíaco , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Masculino , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Neovascularização Fisiológica , Proteínas Proto-Oncogênicas c-kit/metabolismo , Ratos Endogâmicos F344 , Recuperação de Função Fisiológica , Transplante de Células-Tronco/efeitos adversos , Células-Tronco/metabolismo , Fatores de Tempo , Sobrevivência de Tecidos , Ultrassonografia , Pressão Ventricular
19.
PLoS One ; 10(4): e0124227, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25905721

RESUMO

BACKGROUND: There is mounting interest in using c-kit positive human cardiac stem cells (c-kit(pos) hCSCs) to repair infarcted myocardium in patients with ischemic cardiomyopathy. A recent phase I clinical trial (SCIPIO) has shown that intracoronary infusion of 1 million hCSCs is safe. Higher doses of CSCs may provide superior reparative ability; however, it is unknown if doses >1 million cells are safe. To address this issue, we examined the effects of 20 million hCSCs in pigs. METHODS: Right atrial appendage samples were obtained from patients undergoing cardiac surgery. The tissue was processed by an established protocol with eventual immunomagnetic sorting to obtain in vitro expanded hCSCs. A cumulative dose of 20 million cells was given intracoronarily to pigs without stop flow. Safety was assessed by measurement of serial biomarkers (cardiac: troponin I and CK-MB, renal: creatinine and BUN, and hepatic: AST, ALT, and alkaline phosphatase) and echocardiography pre- and post-infusion. hCSC retention 30 days after infusion was quantified by PCR for human genomic DNA. All personnel were blinded as to group assignment. RESULTS: Compared with vehicle-treated controls (n=5), pigs that received 20 million hCSCs (n=9) showed no significant change in cardiac function or end organ damage (assessed by organ specific biomarkers) that could be attributed to hCSCs (P>0.05 in all cases). No hCSCs could be detected in left ventricular samples 30 days after infusion. CONCLUSIONS: Intracoronary infusion of 20 million c-kit positive hCSCs in pigs (equivalent to ~40 million hCSCs in humans) does not cause acute cardiac injury, impairment of cardiac function, or liver and renal injury. These results have immediate translational value and lay the groundwork for using doses of CSCs >1 million in future clinical trials. Further studies are needed to ascertain whether administration of >1 million hCSCs is associated with greater efficacy in patients with ischemic cardiomyopathy.


Assuntos
Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo , Transplante de Células-Tronco , Animais , Feminino , Humanos , Separação Imunomagnética , Miócitos Cardíacos/citologia , Suínos
20.
Am J Health Syst Pharm ; 59(11): 1097-104, 2002 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12063896

RESUMO

The development and implementation of a departmental performance evaluation system for a correctional managed care pharmacy are described. Health care services for approximately 150,000 offenders within the Texas Department of Criminal Justice are provided through an arrangement with two university systems, the University of Texas Medical Branch (UTMB) and Texas Tech University Health Sciences Center. UTMB provides all distributive pharmacy services through a central pharmacy located in Huntsville, Texas. The pharmacy department distributes 9,000-15,000 medication orders daily to over 140 facilities. Each department within UTMB Correctional Managed Care is evaluated against predetermined quality indicators. This evaluation system is collectively called the operational performance evaluation system (OPES) and is used, in part, to determine pay-for-performance eligibility. Before fiscal year 2001, pharmacy distributive services were provided under a third university system. Joining the UTMB system required the pharmacy department to not only participate in OPES but to develop quality indicators and measurement systems to evaluate departmental performance. Indicators were chosen to reflect a commitment to quality while assuring appropriate productivity in the provision of pharmaceutical care. Seven pharmaceutical care quality indicators were chosen and weighted by perceived importance. A system for data collection, measurement, and reporting was also developed. Implementation of a departmental performance evaluation system provides a means to measure service quality, identify areas of weakness, track performance over time, and lower costs. By setting concrete goals, this system raises awareness and promotes interdependence among department personnel.


Assuntos
Serviços Comunitários de Farmácia/organização & administração , Pesquisa sobre Serviços de Saúde/métodos , Programas de Assistência Gerenciada/organização & administração , Prisões/organização & administração , Serviços Comunitários de Farmácia/estatística & dados numéricos , Pesquisa sobre Serviços de Saúde/estatística & dados numéricos , Humanos , Programas de Assistência Gerenciada/estatística & dados numéricos , Prisões/métodos , Prisões/estatística & dados numéricos
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