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1.
J Am Heart Assoc ; 13(9): e032577, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38639350

RESUMO

BACKGROUND: The goal was to determine the feasibility of mapping the injured-but-not-infarcted myocardium using 99mTc-duramycin in the postischemic heart, with spatial information for its characterization as a pathophysiologically intermediate tissue, which is neither normal nor infarcted. METHODS AND RESULTS: Coronary occlusion was conducted in Sprague Dawley rats with preconditioning and 30-minute ligation. In vivo single-photon emission computed tomography was acquired after 3 hours (n=6) using 99mTc-duramycin, a phosphatidylethanolamine-specific radiopharmaceutical. The 99mTc-duramycin+ areas were compared with infarct and area-at-risk (n=8). Cardiomyocytes and endothelial cells were isolated for gene expression profiling. Cardiac function was measured with echocardiography (n=6) at 4 weeks. In vivo imaging with 99mTc-duramycin identified the infarct (3.9±2.4% of the left ventricle and an extensive area 23.7±2.2% of the left ventricle) with diffuse signal outside the infarct, which is pathologically between normal and infarcted (apoptosis 1.8±1.6, 8.9±4.2, 13.6±3.8%; VCAM-1 [vascular cell adhesion molecule 1] 3.2±0.8, 9.8±4.1, 15.9±4.2/mm2; tyrosine hydroxylase 14.9±2.8, 8.6±4.4, 5.6±2.2/mm2), with heterogeneous changes including scattered micronecrosis, wavy myofibrils, hydropic change, and glycogen accumulation. The 99mTc-duramycin+ tissue is quantitatively smaller than the area-at-risk (26.7% versus 34.4% of the left ventricle, P=0.008). Compared with infarct, gene expression in the 99mTc-duramycin+-noninfarct tissue indicated a greater prosurvival ratio (BCL2/BAX [B-cell lymphoma 2/BCL2-associated X] 7.8 versus 5.7 [cardiomyocytes], 3.7 versus 3.2 [endothelial]), and an upregulation of ion channels in electrophysiology. There was decreased contractility at 4 weeks (regional fractional shortening -8.6%, P<0.05; circumferential strain -52.9%, P<0.05). CONCLUSIONS: The injured-but-not-infarcted tissue, being an intermediate zone between normal and infarct, is mapped in vivo using phosphatidylethanolamine-based imaging. The intermediate zone contributes significantly to cardiac dysfunction.


Assuntos
Modelos Animais de Doenças , Infarto do Miocárdio , Peptídeos , Compostos Radiofarmacêuticos , Ratos Sprague-Dawley , Tomografia Computadorizada de Emissão de Fóton Único , Animais , Infarto do Miocárdio/patologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/diagnóstico por imagem , Masculino , Miocárdio/patologia , Miocárdio/metabolismo , Miócitos Cardíacos/patologia , Miócitos Cardíacos/metabolismo , Bacteriocinas/metabolismo , Estudos de Viabilidade , Ratos , Perfilação da Expressão Gênica/métodos , Função Ventricular Esquerda , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Compostos de Organotecnécio
2.
Eur J Radiol ; 160: 110705, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36701824

RESUMO

PURPOSE: The biplane area-length method is commonly used in cardiac magnetic resonance (CMR) to assess left atrial (LA) volume (LAV) and function. Associations between left atrial emptying fraction (LAEF) and clinical outcomes have been reported. However, only limited data are available on the calculation of LAEF using the biplane method compared to 3D assessment. This study aimed to compare volumetric and functional LA parameters obtained from the biplane method with 3D assessment in a large, multiethnic cohort. METHOD: 158 participants of MESA (Multi-Ethnic Study of Atherosclerosis) underwent CMR that included standard two- and four-chamber steady-state free precession (SSFP) cine imaging for the biplane method. For 3D-based assessment, short-axis SSFP cine series covering the entire LA were obtained, followed by manual delineation of LA contours to create a time-resolved 3D LAV dataset. Paired t-tests and Bland-Altman plots were used to analyze the data. RESULTS: Standard volumetric assessment showed that LAVmin (bias: -8.35 mL, p < 0.001), LAVmax (bias: -9.38 mL, p < 0.001) and LAVpreA (bias: -10.27 mL, p < 0.001) were significantly smaller using the biplane method compared to 3D assessment. Additionally, the biplane method reported significantly higher LAEFtotal (bias: 7.22 %, p < 0.001), LAEFactive (bias: 6.08 %, p < 0.001), and LAEFpassive (bias: 4.51 %, p < 0.001) with wide limits of agreement. CONCLUSIONS: LA volumes were underestimated using the biplane method compared to 3D assessment, while LAEF parameters were overestimated. These findings demonstrate a lack of precision using the biplane method for LAEF assessment. Our results support the usage of 3D assessment in specific settings when LA volumetric and functional parameters are in focus.


Assuntos
Fibrilação Atrial , Humanos , Função do Átrio Esquerdo , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/patologia , Imageamento por Ressonância Magnética , Valor Preditivo dos Testes
3.
Nucleic Acids Res ; 50(22): 12979-12996, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36533443

RESUMO

Aggregation of the microtubule-associated protein tau characterizes tauopathies, including Alzheimer's disease and frontotemporal lobar degeneration (FTLD-Tau). Gene expression regulation of tau is complex and incompletely understood. Here we report that the human tau gene (MAPT) generates two circular RNAs (circRNAs) through backsplicing of exon 12 to either exon 7 (12→7 circRNA) or exon 10 (12→10 circRNA). Both circRNAs lack stop codons. The 12→7 circRNA contains one start codon and is translated in a rolling circle, generating a protein consisting of multimers of the microtubule-binding repeats R1-R4. For the 12→10 circRNA, a start codon can be introduced by two FTLD-Tau mutations, generating a protein consisting of multimers of the microtubule-binding repeats R2-R4, suggesting that mutations causing FTLD may act in part through tau circRNAs. Adenosine to inosine RNA editing dramatically increases translation of circRNAs and, in the 12→10 circRNA, RNA editing generates a translational start codon by changing AUA to AUI. Circular tau proteins self-aggregate and promote aggregation of linear tau proteins. Our data indicate that adenosine to inosine RNA editing initiates translation of human circular tau RNAs, which may contribute to tauopathies.


Assuntos
Tauopatias , Proteínas tau , Humanos , Adenosina/metabolismo , Códon de Iniciação , Inosina/metabolismo , RNA/genética , RNA/metabolismo , Edição de RNA , RNA Circular/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo , Tauopatias/genética , Tauopatias/metabolismo
4.
Geroscience ; 44(1): 173-194, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34410588

RESUMO

C-terminal cleaved tau at D421 (∆D421-tau) accumulates in the brains of Alzheimer's disease (AD) patients. However, it is unclear how tau truncation, an understudied tau post-translational modification, contributes to AD pathology and progression. Utilizing an adeno-associated virus (AAV) gene delivery-based approach, we overexpressed full-length tau (FL-tau) and ∆D421-tau in 4- and 12-month-old mice for 4 months to study the neuropathological impact of accumulation in young adult (8-month) and middle-aged (16-month) mice. Overall, we show that independent of the tau species, age was an important factor facilitating tau phosphorylation, oligomer formation, and deposition into silver-positive tangles. However, mice overexpressing ∆D421-tau exhibited a distinct phosphorylation profile to those overexpressing FL-tau and increased tau oligomerization in the middle-age group. Importantly, overexpression of ∆D421-tau, but not FL-tau in middle-aged mice, resulted in pronounced cognitive impairments and hippocampal long-term potentiation deficits. While both FL-tau and ∆D421-tau induced neuronal loss in mice with age, ∆D421-tau led to significant neuronal loss in the CA3 area of the hippocampus and medial entorhinal cortex compared to FL-tau. Based on our data, we conclude that age increases the susceptibility to neuronal degeneration associated with ΔD421-tau accumulation. Our findings suggest that ΔD421-tau accumulation contributes to synaptic plasticity and cognitive deficits, thus representing a potential target for tau-associated pathologies.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/genética , Animais , Cognição , Disfunção Cognitiva/patologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Plasticidade Neuronal
5.
Front Immunol ; 12: 628156, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34046031

RESUMO

Brain myeloid cells, include infiltrating macrophages and resident microglia, play an essential role in responding to and inducing neurodegenerative diseases, such as Alzheimer's disease (AD). Genome-wide association studies (GWAS) implicate many AD casual and risk genes enriched in brain myeloid cells. Coordinated arginine metabolism through arginase 1 (Arg1) is critical for brain myeloid cells to perform biological functions, whereas dysregulated arginine metabolism disrupts them. Altered arginine metabolism is proposed as a new biomarker pathway for AD. We previously reported Arg1 deficiency in myeloid biased cells using lysozyme M (LysM) promoter-driven deletion worsened amyloidosis-related neuropathology and behavioral impairment. However, it remains unclear how Arg1 deficiency in these cells impacts the whole brain to promote amyloidosis. Herein, we aim to determine how Arg1 deficiency driven by LysM restriction during amyloidosis affects fundamental neurodegenerative pathways at the transcriptome level. By applying several bioinformatic tools and analyses, we found that amyloid-ß (Aß) stimulated transcriptomic signatures in autophagy-related pathways and myeloid cells' inflammatory response. At the same time, myeloid Arg1 deficiency during amyloidosis promoted gene signatures of lipid metabolism, myelination, and migration of myeloid cells. Focusing on Aß associated glial transcriptomic signatures, we found myeloid Arg1 deficiency up-regulated glial gene transcripts that positively correlated with Aß plaque burden. We also observed that Aß preferentially activated disease-associated microglial signatures to increase phagocytic response, whereas myeloid Arg1 deficiency selectively promoted homeostatic microglial signature that is non-phagocytic. These transcriptomic findings suggest a critical role for proper Arg1 function during normal and pathological challenges associated with amyloidosis. Furthermore, understanding pathways that govern Arg1 metabolism may provide new therapeutic opportunities to rebalance immune function and improve microglia/macrophage fitness.


Assuntos
Doença de Alzheimer/enzimologia , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Arginase/metabolismo , Encéfalo/enzimologia , Perfilação da Expressão Gênica , Microglia/enzimologia , Células Mieloides/enzimologia , Degeneração Neural , Transcriptoma , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Animais , Arginase/genética , Encéfalo/patologia , Modelos Animais de Doenças , Feminino , Redes Reguladoras de Genes , Haploinsuficiência , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/patologia , Mutação , Células Mieloides/patologia
6.
Bone Marrow Transplant ; 56(1): 50-59, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32612255

RESUMO

We compared three fludarabine-based regimens for systemic sclerosis patients with a high-risk cardiac phenotype that according to EBMT criteria would be a contraindication for a high-dose cyclophosphamide (200 mg/kg) transplant regimen. All three regimens included fludarabine, ATG, and cyclophosphamide (60 mg/kg), while two regimens also included rituximab with or without IVIG. Treatment related mortality (TRM) was 2.4%. The mean number of days of neutropenia (ANC < 500) was 5.2, the mean number of platelet and red blood cell transfusions was 0.3 and 1.85, respectively. Skin score, forced vital capacity (FVC), and total lung capacity (TLC) improved with all three regimens. For patients whose regimen did not include rituximab versus those that included rituximab, 1-year overall relapse rate was higher 36% (5/14) versus 3.6% (1 of 28) (p = 0.01), secondary autoimmune diseases were higher 21% (3/14) versus 0% (0/28) (p = 0.03), and upper respiratory tract infections were higher 28% (4/14) versus 3.6% (1/28) (p = 0.04). In this safety study, a fludarabine-based regimen was relatively safe with a TRM of 2.4% and a neutropenic interval of only 5.2 days in systemic sclerosis patients with a high-risk cardiac phenotype. The addition of rituximab decreased 1-year relapse rate, risk of late secondary autoimmune diseases, and upper-respiratory tract infections.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Escleroderma Sistêmico , Ciclofosfamida , Humanos , Recidiva Local de Neoplasia , Condicionamento Pré-Transplante , Vidarabina
7.
J Vasc Surg Cases Innov Tech ; 6(4): 490-492, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33134626

RESUMO

Penetrating subdiaphragmatic aortic trauma is associated with high morbidity and mortality with studies having reported a 50%-70% associated mortality. We describe a case of a patient with a subdiaphragmatic aortic injury caused by a 7.4-cm common nail that traversed through his L1 vertebral body into the aorta. His aortic injury was managed jointly with vascular surgery and neurosurgery teams.

8.
Front Immunol ; 11: 997, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508844

RESUMO

Innate immune activation is a major contributor to Alzheimer's Disease (AD) pathophysiology, although the mechanisms involved are poorly understood. Chemokine C-C motif ligand (CCL) 2 is produced by neurons and glial cells and is upregulated in the AD brain. Transgene expression of CCL2 in mouse models of amyloidosis produces microglia-induced amyloid ß oligomerization, a strong indication of the role of these activation pathways in the amyloidogenic processes of AD. We have previously shown that CCL2 polarizes microglia in wild type mice. However, how CCL2 signaling contributes to tau pathogenesis remains unknown. To address this question, CCL2 was delivered via recombinant adeno-associated virus serotype 9 into both cortex and hippocampus of a mouse model with tau pathology (rTg4510). We report that CCL2 overexpression aggravated tau pathology in rTg4510 as shown by the increase in Gallyas stained neurofibrillary tangles as well as phosphorylated tau-positive inclusions. In addition, biochemical analysis showed a reduction in the levels of detergent-soluble tau species followed by increase in the insoluble fraction, indicating a shift toward larger tau aggregates. Indeed, increased levels of high molecular weight species of phosphorylated tau were found in the mice injected with CCL2. We also report that worsening of tau pathology following CCL2 overexpression was accompanied by a distinct inflammatory response. We report an increase in leukocyte common antigen (CD45) and Cluster of differentiation 68 (CD68) expression in the brain of rTg4510 mice without altering the expression levels of a cell-surface protein Transmembrane Protein 119 (Tmem119) and ionized calcium-binding adaptor molecule 1 (Iba-1) in resident microglia. Furthermore, the analysis of cytokines in brain extract showed a significant increase in interleukin (IL)-6 and CCL3, while CCL5 levels were decreased in CCL2 mice. No changes were observed in IL-1α, IL-1ß, TNF-α. IL-4, Vascular endothelial growth factor-VEGF, IL-13 and CCL11. Taken together our data report for the first time that overexpression of CCL2 promotes the increase of pathogenic tau species and is associated with glial neuroinflammatory changes that are deleterious. We propose that these events may contribute to the pathogenesis of Alzheimer's disease and other tauopathies.


Assuntos
Encéfalo/metabolismo , Quimiocina CCL2/metabolismo , Neuroglia/metabolismo , Tauopatias/metabolismo , Proteínas tau/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Encéfalo/imunologia , Encéfalo/patologia , Quimiocina CCL2/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Feminino , Mediadores da Inflamação/metabolismo , Masculino , Camundongos Transgênicos , Mutação , Neuroglia/imunologia , Neuroglia/patologia , Presenilina-1/genética , Presenilina-1/metabolismo , Transdução de Sinais , Tauopatias/genética , Tauopatias/imunologia , Tauopatias/patologia , Regulação para Cima , Proteínas tau/genética
9.
Soft Matter ; 16(15): 3762-3768, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32239011

RESUMO

Cell therapy for spinal cord injuries offers the possibility of replacing lost cells after trauma to the central nervous system (CNS). In preclinical studies, synthetic hydrogels are often co-delivered to the injury site to support survival and integration of the transplanted cells. These hydrogels ideally mimic the mechanical and biochemical features of a healthy CNS extracellular matrix while also providing the possibility of localized drug delivery to promote healing. In this work, we synthesize peptide-functionalized polymers that contain both a peptide sequence for incorporation into self-assembled peptide hydrogels along with bioactive peptides that inhibit scar formation. We demonstrate that peptide hydrogels formulated with the peptide-functionalized polymers possess similar mechanical properties (soft and shear-thinning) as peptide-only hydrogels. Small angle neutron scattering analysis reveals that polymer-containing hydrogels possess larger inhomogeneous domains but small-scale features such as mesh size remain the same as peptide-only hydrogels. We further confirm that the integrated hydrogels containing bioactive peptides exhibit thrombin inhibition activity, which has previously shown to reduce scar formation in vivo. Finally, while the survival of encapsulated cells was poor, cells cultured on the hydrogels exhibited good viability. Overall, the described composite hydrogels formed from self-assembling peptides and peptide-modified polymers are promising, user-friendly materials for CNS applications in regeneration.


Assuntos
Células Imobilizadas/metabolismo , Hidrogéis/química , Peptídeos/química , Células-Tronco/metabolismo , Trombina/química , Animais , Células Imobilizadas/citologia , Humanos , Camundongos , Células-Tronco/citologia
10.
Front Immunol ; 11: 582998, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33519806

RESUMO

Alzheimer's disease (AD) includes several hallmarks comprised of amyloid-ß (Aß) deposition, tau neuropathology, inflammation, and memory impairment. Brain metabolism becomes uncoupled due to aging and other AD risk factors, which ultimately lead to impaired protein clearance and aggregation. Increasing evidence indicates a role of arginine metabolism in AD, where arginases are key enzymes in neurons and glia capable of depleting arginine and producing ornithine and polyamines. However, currently, it remains unknown if the reduction of arginase 1 (Arg1) in myeloid cell impacts amyloidosis. Herein, we produced haploinsufficiency of Arg1 by the hemizygous deletion in myeloid cells using Arg1fl/fl and LysMcreTg/+ mice crossed with APP Tg2576 mice. Our data indicated that Arg1 haploinsufficiency promoted Aß deposition, exacerbated some behavioral impairment, and decreased components of Ragulator-Rag complex involved in mechanistic target of rapamycin complex 1 (mTORC1) signaling and autophagy. Additionally, Arg1 repression and arginine supplementation both impaired microglial phagocytosis in vitro. These data suggest that proper function of Arg1 and arginine metabolism in myeloid cells remains essential to restrict amyloidosis.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Amiloidose/metabolismo , Arginase/metabolismo , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/metabolismo , Células Mieloides/fisiologia , Animais , Arginase/genética , Autofagia , Comportamento Animal , Modelos Animais de Doenças , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Camundongos Transgênicos , Inflamação Neurogênica , Transdução de Sinais
11.
Forensic Sci Med Pathol ; 16(1): 171-176, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31773473

RESUMO

Acanthamoeba spp. and Balamuthia mandrillaris are free-living amebae known to cause disseminated and fatal central nervous system dysfunction which manifests as granulomatous amebic encephalitis (GAE) with exceedingly rare frequency. We report two lethal cases of infection with free-living amebae: an acute case of Acanthamoeba spp. infection in an immunocompromised female and a subacute case of B. mandrillaris in a Hispanic male. The Acanthamoeba spp. infection presented with an atypical lesion in the thalamus that caused rapid deterioration of the patient while the case of B. mandrillaris had a prolonged clinical course with multifocal lesions beginning in the frontal lobe. Cerebrospinal fluid results were non-specific in both cases, however, post-mortem histology demonstrated the presence of trophozoites along a perivascular distribution of necrosis and infiltrate composed primarily of neutrophils. In addition to detailing the clinical presentations of these infrequent amebic infections, we offer insight into the difficulties surrounding their diagnoses in order to aid the clinician in accurate and timely identification.


Assuntos
Acanthamoeba , Balamuthia mandrillaris , Infecções Protozoárias do Sistema Nervoso Central/diagnóstico , Granuloma/parasitologia , Encefalite Infecciosa/parasitologia , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Evolução Fatal , Feminino , Humanos , Hospedeiro Imunocomprometido , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tálamo/diagnóstico por imagem , Tomografia Computadorizada por Raios X
12.
Pacing Clin Electrophysiol ; 43(2): 159-166, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31797387

RESUMO

INTRODUCTION: A recent study reported that diffuse left ventricular (LV) fibrosis is a predictor of atrial fibrillation (AF) recurrence following catheter ablation, by measuring postcontrast cardiac T1 (an error prone metric as per the 2017 Society for Cardiovascular Magnetic Resonance consensus statement) using an inversion-recovery pulse sequence (an error prone method in arrhythmia) in AF ablation candidates. The purpose of this study was to verify the prior study, by measuring extracellular volume (ECV) fraction (an accurate metric) using a saturation-recovery pulse sequence (accurate method in arrhythmia). METHODS AND RESULTS: This study examined 100 AF patients (mean age = 62 ± 11 years, 69 males and 31 females, 67 paroxysmal [pAF] and 33 persistent [peAF]) who underwent a preablation cardiovascular magnetic resonance (CMR) exam. LV ECV and left atrial (LA) and LV functional parameters were quantified using standard analysis methods. During an average follow-up period of 457 ± 261 days with 4 ± 3 rhythm checks per patient, 72 patients maintained sinus rhythm. Between those who maintained sinus rhythm (n = 72) and those who reverted to AF (n = 28), the only clinical characteristic that was significantly different was age (60 ± 12 years vs 66 ± 9 years); for CMR metrics, neither mean LV ECV (25.1 ± 3.3% vs 24.7 ± 3.7%), native LV T1 (1093.8 ± 73.5 ms vs 1070.2 ± 115.9 ms), left ventricular ejection fraction (54.1 ± 11.2% vs 55.7 ± 7.1%), nor LA end diastolic volume/body surface area (42.4 ± 14.8 mL/m2 vs 43.4 ± 19.6 mL/m2 ) were significantly different (P ≥ .23). According to Cox regression tests, none of the clinical and imaging variables predict AF recurrence. CONCLUSION: Neither LV ECV nor other CMR metrics predict recurrence of AF following catheter ablation.


Assuntos
Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Ablação por Cateter , Imageamento por Ressonância Magnética/métodos , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/diagnóstico por imagem , Idoso , Meios de Contraste , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Recidiva
13.
Mol Cell Neurosci ; 102: 103418, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31705957

RESUMO

AIMS: The current study utilizes the adeno-associated viral gene transfer system in the CAMKIIα-tTA mouse model to overexpress human wild type TDP-43 (wtTDP-43) and α-synuclein (α-Syn) proteins. The co-existence of these proteins is evident in the pathology of neurodegenerative disorders such as frontotemporal lobar degeneration (FTLD), Parkinson disease (PD), and dementia with Lewy bodies (DLB). METHODS: The novel bicistronic recombinant adeno-associated virus (rAAV) serotype 9 drives wtTDP-43 and α-Syn expression in the hippocampus via "TetO" CMV promoter. Behavior, electrophysiology, and biochemical and histological assays were used to validate neuropathology. RESULTS: We report that overexpression of wtTDP-43 but not α-Syn contributes to hippocampal CA2-specific pyramidal neuronal loss and overall hippocampal atrophy. Further, we report a reduction of hippocampal long-term potentiation and decline in learning and memory performance of wtTDP-43 expressing mice. Elevated wtTDP-43 levels induced selective degeneration of Purkinje cell protein 4 (PCP-4) positive neurons while both wtTDP-43 and α-Syn expression reduced subsets of the glutamate receptor expression in the hippocampus. CONCLUSIONS: Overall, our findings suggest the significant vulnerability of hippocampal neurons toward elevated wtTDP-43 levels possibly via PCP-4 and GluR-dependent calcium signaling pathways. Further, we report that wtTDP-43 expression induced selective CA2 subfield degeneration, contributing to the deterioration of the hippocampal-dependent cognitive phenotype.


Assuntos
Região CA2 Hipocampal/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Potenciação de Longa Duração , Memória , Animais , Região CA2 Hipocampal/fisiologia , Proteínas de Ligação a DNA/genética , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Aprendizagem em Labirinto , Camundongos , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Células Piramidais/metabolismo , Células Piramidais/fisiologia , Receptores de Glutamato/genética , Receptores de Glutamato/metabolismo , alfa-Sinucleína/metabolismo
14.
J Hand Microsurg ; 11(Suppl 1): S31-S35, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31616124

RESUMO

Purpose Primary cutaneous T-cell lymphoma (CTCL) is a rare diagnosis, and the subset primary cutaneous peripheral T-cell lymphoma (pcPTL) is even more uncommon. Both CTCLs and pcPTLs typically occur in the head and neck. The authors aim to evaluate the literature for reports of presentation in the hand. Materials and Methods A case report of a 77-year-old man with pcPTL of the hand is presented. Oncologic workup revealed an independent diagnosis of medullary thyroid carcinoma. A review of the literature was performed using the following search terms in the PubMed database: primary, cutaneous, T-cell lymphoma, peripheral presentation, and hand. One case of pcPTL in the hand was identified and included in this study. Results One case report in the literature was identified describing a 78-year-old man with a 1-year history of a progressive hand lesion. Biopsy revealed pcPTL. Conclusion This report presents a rare presentation of pcPTL in the hand, reviews the current literature, and provides insight into management. Prompt biopsy of any unresolving lesion of the hand is crucial to expedite diagnosis and treatment of otherwise difficult to diagnose pathologies. Increased awareness of rare malignancies is important to avoid delay in patient care and to improve outcomes.

15.
Circ Res ; 121(8): 930-940, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-28851810

RESUMO

RATIONALE: Clinical benefits of reperfusion after myocardial infarction are offset by maladaptive innate immune cell function, and therapeutic interventions are lacking. OBJECTIVE: We sought to test the significance of phagocytic clearance by resident and recruited phagocytes after myocardial ischemia reperfusion. METHODS AND RESULTS: In humans, we discovered that clinical reperfusion after myocardial infarction led to significant elevation of the soluble form of MerTK (myeloid-epithelial-reproductive tyrosine kinase; ie, soluble MER), a critical biomarker of compromised phagocytosis by innate macrophages. In reperfused mice, macrophage Mertk deficiency led to decreased cardiac wound debridement, increased infarct size, and depressed cardiac function, newly implicating MerTK in cardiac repair after myocardial ischemia reperfusion. More notably, Mertk(CR) mice, which are resistant to cleavage, showed significantly reduced infarct sizes and improved systolic function. In contrast to other cardiac phagocyte subsets, resident cardiac MHCIILOCCR2- (major histocompatibility complex II/C-C motif chemokine receptor type 2) macrophages expressed higher levels of MerTK and, when exposed to apoptotic cells, secreted proreparative cytokines, including transforming growth factor-ß. Mertk deficiency compromised the accumulation of MHCIILO phagocytes, and this was rescued in Mertk(CR) mice. Interestingly, blockade of CCR2-dependent monocyte infiltration into the heart reduced soluble MER levels post-ischemia reperfusion. CONCLUSIONS: Our data implicate monocyte-induced MerTK cleavage on proreparative MHCIILO cardiac macrophages as a novel contributor and therapeutic target of reperfusion injury.


Assuntos
Macrófagos/enzimologia , Traumatismo por Reperfusão Miocárdica/enzimologia , Miocárdio/enzimologia , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Infarto do Miocárdio com Supradesnível do Segmento ST/enzimologia , Animais , Apoptose , Citocinas/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Predisposição Genética para Doença , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Imunidade Inata , Macrófagos/imunologia , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Monócitos/enzimologia , Monócitos/imunologia , Traumatismo por Reperfusão Miocárdica/imunologia , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/imunologia , Miocárdio/patologia , Fagocitose , Fenótipo , Proteólise , Proteínas Proto-Oncogênicas/deficiência , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/imunologia , Receptores Proteína Tirosina Quinases/deficiência , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/imunologia , Receptores CCR2/genética , Receptores CCR2/imunologia , Receptores CCR2/metabolismo , Infarto do Miocárdio com Supradesnível do Segmento ST/imunologia , Infarto do Miocárdio com Supradesnível do Segmento ST/patologia , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Transdução de Sinais , Fatores de Tempo , c-Mer Tirosina Quinase
16.
Neuromolecular Med ; 19(2-3): 322-344, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28620826

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder characterized by alpha-synuclein accumulation and loss of dopaminergic neurons in the substantia nigra (SN) region of the brain. Increased levels of alpha-synuclein have been shown to result in loss of mitochondrial electron transport chain complex I activity leading to increased reactive oxygen species (ROS) production. WT alpha-synuclein was stably overexpressed in human BE(2)-M17 neuroblastoma cells resulting in increased levels of an alpha-synuclein multimer, but no increase in alpha-synuclein monomer levels. Oxygen consumption was decreased by alpha-synuclein overexpression, but ATP levels did not decrease and ROS levels did not increase. Treatment with ferrous sulfate, a ROS generator, resulted in decreased oxygen consumption in both control and alpha-synuclein overexpressing cells. However, this treatment only decreased ATP levels and increased ROS production in the cells overexpressing alpha-synuclein. Similarly, paraquat, another ROS generator, decreased ATP levels in the alpha-synuclein overexpressing cells, but not in the control cells, further demonstrating how alpha-synuclein sensitized the cells to oxidative insult. Proteomic analysis yielded molecular insights into the cellular adaptations to alpha-synuclein overexpression, such as the increased abundance of many mitochondrial proteins. Many amino acids and citric acid cycle intermediates and their ester forms were individually supplemented to the cells with L-serine, L-proline, L-aspartate, or L-glutamine decreasing ROS production in oxidatively stressed alpha-synuclein overexpressing cells, while diethyl oxaloacetate or L-valine supplementation increased ATP levels. These results suggest that dietary supplementation with individual metabolites could yield bioenergetic improvements in PD patients to delay loss of dopaminergic neurons.


Assuntos
Aminoácidos/farmacologia , Metabolismo Energético/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , alfa-Sinucleína/metabolismo , Trifosfato de Adenosina/metabolismo , Linhagem Celular Tumoral , Meios de Cultura/farmacologia , Avaliação Pré-Clínica de Medicamentos , Compostos Ferrosos/farmacologia , Humanos , Mitocôndrias/metabolismo , Neuroblastoma/patologia , Neurônios/metabolismo , Estresse Oxidativo , Consumo de Oxigênio/efeitos dos fármacos , Paraquat/farmacologia , Proteínas Recombinantes/metabolismo , alfa-Sinucleína/genética
17.
Alzheimers Res Ther ; 8(1): 43, 2016 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-27756387

RESUMO

BACKGROUND: There is a need to investigate biomarkers that are indicative of the progression of dementia in ethnic patient populations. The disparity of information in these populations has been the focus of many clinical and academic centers, including ours, to contribute to a higher success rate in clinical trials. In this study, we have investigated plasma biomarkers in amnestic mild cognitively impaired (aMCI) female patient cohorts in the context of ethnicity and cognitive status. METHOD: A panel of 12 biomarkers involved in the progression of brain pathology, inflammation, and cardiovascular disorders were investigated in female cohorts of African American, Hispanic, and White aMCI patients. Both biochemical and algorithmic analyses were applied to correlate biomarker levels measured during the early stages of the disease for each ethnicity. RESULTS: We report elevated plasma Aß40, Aß42, YKL-40, and cystatin C levels in the Hispanic cohort at early aMCI status. In addition, elevated plasma Aß40 levels were associated with the aMCI status in both White and African American patient cohorts by the decision tree algorithm. Eotaxin-1 levels, as determined by the decision tree algorithm and biochemically measured total tau levels, were associated with the aMCI status in the African American cohort. CONCLUSIONS: Overall, our data displayed novel differences in the plasma biomarkers of the aMCI female cohorts where the plasma levels of several biomarkers distinguished between each ethnicity at an early aMCI stage. Identification of these plasma biomarkers encourages new areas of investigation among aMCI ethnic populations, including larger patient cohorts and longitudinal study designs.


Assuntos
Biomarcadores/sangue , Demência , Negro ou Afro-Americano , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Peptídeos beta-Amiloides/sangue , Proteína 1 Semelhante à Quitinase-3/sangue , Estudos de Coortes , Cistatina C/sangue , Árvores de Decisões , Demência/sangue , Demência/epidemiologia , Demência/etnologia , Ensaio de Imunoadsorção Enzimática , Feminino , Hispânico ou Latino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Progranulinas , População Branca
18.
NMR Biomed ; 29(10): 1454-63, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27593977

RESUMO

This study was conducted to improve the precision of arrhythmia-insensitive rapid (AIR) cardiac T1 mapping through pulse sequence optimization and then evaluate the intra-scan repeatability in patients at 3T against investigational modified Look-Locker inversion recovery (MOLLI) T1 mapping. In the first development phase (five human subjects), we implemented and tested centric-pair k-space ordering to suppress image artifacts associated with eddy currents. In the second development phase (15 human subjects), we determined optimal flip angles to reduce the measurement variation in T1 maps. In the validation phase (35 patients), we compared the intra-scan repeatability between investigational MOLLI and optimized AIR. In 23 cardiac planes, conventional centric k-space ordering (3.7%) produced significantly (p < 0.05) more outliers as a fraction of left ventricular cavity area than optimal centric k-space ordering (1.4%). In 15 human subjects, for each of four types of measurement (native myocardial T1 , native blood T1 , post-contrast myocardial T1 , post-contrast blood T1 ), flip angles of 55-65° produced lower measurement variation while producing results that are not significantly different from those produced with the previously used flip angle of 35° (p > 0.89, intra-class correlation coefficient ≥ 0.95 for all four measurement types). Compared with investigational MOLLI (coefficient of repeatability, CR = 40.0, 77.2, 26.5, and 25.9 ms for native myocardial, native blood, post-contrast myocardial, and post-contrast blood T1 , and 2.0% for extracellular volume (ECV) measurements, respectively), optimized AIR (CR = 54.3, 89.7, 30.5, and 14.7 ms for native myocardial, native blood, post-contrast myocardial, and post-contrast blood T1 , and 1.6% for ECV measurements, respectively) produced similar absolute intra-scan repeatability in all 35 patients in the validation phase. High repeatability is critically important for longitudinal studies, where the goal is to monitor physiologic/pathologic changes, not measurement variation. Optimized AIR cardiac T1 mapping is likely to yield high scan-retest repeatability for pre-clinical and clinical applications.


Assuntos
Técnicas de Imagem Cardíaca/métodos , Cardiopatias/diagnóstico por imagem , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Processamento de Sinais Assistido por Computador , Adulto , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
19.
Medicine (Baltimore) ; 95(18): e3466, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27149446

RESUMO

In experimental myocardial infarction (MI), a rise in cell counts of circulating monocyte subsets contributes to impaired myocardial healing and to atherosclerotic plaque destabilization. In humans, the prognostic role of monocyte subsets in patients suffering ST-elevation MI (STEMI) is still unclear. In the present study, we aimed to determine the kinetics of the 3 monocyte subsets (classical CD14++CD16-, intermediate CD14++CD16+, and nonclassical CD14+CD16++ monocytes), as well as the subset-specific monocyte-platelet aggregates (MPA), in acute STEMI followed by primary percutaneous coronary intervention (PCI), and their relationships with cardiovascular outcomes during a 2-year follow-up.Monocyte subsets and MPA were measured in 100 STEMI patients receiving primary PCI on days 1, 2, 3, 5, and 7 of symptom onset, which were compared with 60 stable coronary heart disease patients and 35 healthy volunteers. From day 1 to day 7, significant increases in the counts of CD14++CD16+ monocytes and CD14++CD16+ MPA were observed, with peak levels on day 2. During a median follow-up of 2.0 years, 28 first cardiovascular events (defined as cardiovascular death, nonfatal ischemic stroke, recurrent MI, need for emergency or repeat revascularization, and rehospitalization for heart failure) were recorded. After adjustment for confounders, CD14++CD16+ monocytosis (day 1 [HR: 3.428; 95% CI: 1.597-7.358; P = 0.002], day 2 [HR: 4.835; 95% CI: 1.106-21.13; P = 0.04], day 3 [HR: 2.734; 95% CI: 1.138-6.564; P = 0.02], and day 7 [HR: 2.647; 95% CI: 1.196-5.861; P = 0.02]), as well as increased levels of CD14++CD16+ MPA measured on all time points (days 1, 2, 3, 5, and 7), had predictive values for adverse cardiovascular events.In conclusion, our data show the expansion of the CD14++CD16+ monocyte subset during acute phase of STEMI has predictive values for 2-year adverse cardiovascular outcomes in patients treated with primary PCI. Future studies will be warranted to elucidate whether CD14++CD16+ monocytes may become a target cell population for new therapeutic strategies after STEMI.


Assuntos
Antígenos CD/análise , Plaquetas/metabolismo , Monócitos , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Idoso , Agregação Celular , China , Angiografia Coronária/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/classificação , Monócitos/metabolismo , Readmissão do Paciente/estatística & dados numéricos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Período Pós-Operatório , Valor Preditivo dos Testes , Recidiva , Reoperação/estatística & dados numéricos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia
20.
J Clin Monit Comput ; 30(5): 519-26, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26873749

RESUMO

To compare the performance of a bioreactance cardiac output (CO) monitor (NICOM) and transcutaneous Doppler (USCOM) during head up tilting (HUT). Healthy young adult subjects, age 22 ± 1 years, 7 male and 7 female, were tilted over 3-5 s from supine to 70° HUT, 30° HUT and back to supine. Positions were held for 3 min. Simultaneous readings of NICOM and USCOM were performed 30 s into each new position. Mean blood pressure (MBP), heart rate (HR), CO and stroke volume (SV), and thoracic fluid content (TFC) were recorded. Bland-Altman, percentage changes and analysis of variance for repeated measures were used for statistical analysis. Pre-tilt NICOM CO and SV readings (6.1 ± 1.0 L/min and 113 ± 25 ml) were higher than those from USCOM (4.1 ± 0.6 L/min and 77 ± 9 ml) (P < 0.001). Bland-Altman limits of agreement for CO were wide with a percentage error of 38 %. HUT increased MBP and HR (P < 0.001). CO and SV readings decreased with HUT. However, the percentage changes in USCOM and NICOM readings did not concur (P < 0.001). Whereas USCOM provided gravitational effect proportional changes in SV readings of 23 ± 15 % (30° half tilt) and 44 ± 11 % (70° near full tilt), NICOM changes did not being 28 ± 10 and 33 ± 11 %. TFC decreased linearly with HUT. The NICOM does not provide linear changes in SV as predicted by physiology when patients are tilted. Furthermore there is a lack of agreement with USCOM measurements at baseline and during tilting.


Assuntos
Débito Cardíaco/fisiologia , Ecocardiografia Doppler/métodos , Posicionamento do Paciente , Volume Sistólico/fisiologia , Termodiluição/métodos , Cateterismo , Feminino , Voluntários Saudáveis , Frequência Cardíaca/fisiologia , Hemodinâmica , Humanos , Modelos Lineares , Masculino , Monitorização Fisiológica , Artéria Pulmonar/patologia , Adulto Jovem
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