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1.
Exp Neurol ; 359: 114241, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36240881

RESUMO

Traumatic brain injury (TBI) acutely damages the brain; this injury can evolve into chronic neurodegeneration. While much is known about the chronic effects arising from multiple mild TBIs, far less is known about the long-term effects of a single moderate to severe TBI. We found that a single moderate closed head injury to mice induces diffuse axonal injury within 1-day post-injury (DPI). At 14 DPI, injured animals have atrophy of ipsilesional cortex, thalamus, and corpus callosum, with bilateral atrophy of the dorsal fornix. Atrophy of the ipsilesional corpus callosum is accompanied by decreased fractional anisotropy and increased mean and radial diffusivity that remains unchanged between 14 and 180 DPI. Injured animals show an increased density of phospho-tau immunoreactive (pTau+) cells in the ipsilesional cortex and thalamus, and bilaterally in corpus callosum. Between 14 and 180 DPI, atrophy occurs in the ipsilesional ventral fornix, contralesional corpus callosum, and bilateral internal capsule. Diffusion tensor MRI parameters remain unchanged in white matter regions with delayed atrophy. Between 14 and 180 DPI, pTau+ cell density increases bilaterally in corpus callosum, but decreases in cortex and thalamus. The location of pTau+ cells within the ipsilesional corpus callosum changes between 14 and 180 DPI; density of all cells increases including pTau+ or pTau- cells. >90% of the pTau+ cells are in the oligodendrocyte lineage in both gray and white matter. Density of thioflavin-S+ cells in thalamus increases by 180 DPI. These data suggest a single closed head impact produces multiple forms of chronic neurodegeneration. Gray and white matter regions proximal to the impact site undergo early atrophy. More distal white matter regions undergo chronic, progressive white matter atrophy with an increasing density of oligodendrocytes containing pTau. These data suggest a complex chronic neurodegenerative process arising from a single moderate closed head injury.


Assuntos
Lesões Encefálicas Traumáticas , Traumatismos Cranianos Fechados , Substância Branca , Animais , Camundongos , Masculino , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Imagem de Tensor de Difusão , Lesões Encefálicas Traumáticas/patologia , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/patologia , Oligodendroglia , Atrofia/patologia , Traumatismos Cranianos Fechados/patologia
2.
PLoS One ; 15(11): e0239780, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33253224

RESUMO

The cocaine vaccine dAd5GNE is comprised of a disrupted serotype 5 adenovirus gene therapy vector covalently conjugated to the cocaine analog GNE. The vaccine evokes a high titer of circulating anti-cocaine antibodies that prevent cocaine from reaching its cognate receptors in the central nervous system. Prior studies have demonstrated the efficacy of dAd5GNE in models of occasional, moderate cocaine use. However, previous studies have not sufficiently evaluated the efficacy of dAd5GNE in models of the repetitive and high-dose "binge" use patterns common in human addicts. In the present study, we evaluated the capacity of dAd5GNE vaccination to protect against "binge" cocaine use and circumstances where vaccinated addicts attempt to override the vaccine. We modeled repetitive daily cocaine use in vaccinated Balb/c mice and African green monkeys, and evaluated high-dose "binge" scenarios in Balb/c mice. In each model of daily use the dAd5GNE vaccine prevented cocaine from reaching the central nervous system. In the high-dose "binge" model, vaccination decreased cocaine-induced hyperactivity and reduced the number of cocaine-induced seizures. Based on this data and our prior data in rodents and nonhuman primates, we have initiated a clinical trial evaluating the dAd5GNE anti-cocaine vaccine as a potential therapy for cocaine addicts who wish to stop cocaine use. If dAd5GNE vaccination is safe and produces high anti-cocaine antibody titers in the clinic, we hypothesize that the vaccine will restrict the access of cocaine to the central nervous system and inhibit cocaine-induced "highs" even in the context of moderate daily and high-dose "binge" use that might otherwise cause a drug-induced overdose.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/prevenção & controle , Cocaína/análogos & derivados , Cocaína/imunologia , Adenoviridae/genética , Animais , Anticorpos/sangue , Anticorpos/imunologia , Chlorocebus aethiops , Cocaína/administração & dosagem , Cocaína/efeitos adversos , Cocaína/uso terapêutico , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Receptores de Droga/metabolismo , Vacinação , Vacinas/uso terapêutico
3.
Hum Gene Ther ; 31(1-2): 57-69, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31608704

RESUMO

Chronic traumatic encephalopathy (CTE) is a progressive neurodegenerative disorder caused by repetitive trauma to the central nervous system (CNS) suffered by soldiers, contact sport athletes, and civilians following accident-related trauma. CTE is a CNS tauopathy, with trauma-induced inflammation leading to accumulation of hyperphosphorylated forms of the microtubule-binding protein Tau (pTau), resulting in neurofibrillary tangles and progressive loss of neurons. At present, there are no therapies to treat CTE. We hypothesized that direct CNS administration of an adeno-associated virus (AAV) vector coding for an anti-pTau antibody would generate sufficient levels of anti-pTau in the CNS to suppress pTau accumulation thus interrupting the pathogenic process. Using a serotype AAVrh.10 gene transfer vector coding for a monoclonal antibody directed against pTau, we demonstrate the feasibility of this strategy in a murine CTE model in which pTau accumulation was elicited by repeated traumatic brain injury (TBI) using a closed cortical impact procedure over 5 days. Direct delivery of AAVrh.10 expression vectors coding for either of the two different anti-pTau antibodies to the hippocampus of these TBI mice significantly reduced pTau levels across the CNS. Using doses that can be safely scaled to humans, the data demonstrate that CNS administration of AAVrh.10anti-pTau is effective, providing a new strategy to interrupt the CTE consequences of TBI.


Assuntos
Encefalopatia Traumática Crônica/genética , Encefalopatia Traumática Crônica/terapia , Terapia Genética , Proteínas tau/genética , Animais , Anticorpos Monoclonais/farmacologia , Encéfalo/metabolismo , Encéfalo/patologia , Dependovirus/genética , Gerenciamento Clínico , Modelos Animais de Doenças , Suscetibilidade a Doenças , Terapia Genética/efeitos adversos , Terapia Genética/métodos , Vetores Genéticos/genética , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Transgênicos , Neurônios/metabolismo , Ligação Proteica , Proteínas tau/antagonistas & inibidores , Proteínas tau/metabolismo
4.
Environ Sci Pollut Res Int ; 25(30): 30488-30496, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30168111

RESUMO

High concentrations of airborne asbestos in the ambient air are still a serious problem of air quality in numerous localities around the world. Since 2002, elevated concentrations of asbestos minerals of unknown origin have been detected in the ambient air of Pilsen, Czech Republic. To determine the asbestos fibre sources in this urban air, a systematic study was conducted. First, 14 bulk dust samples were collected in Pilsen at nine localities, and 6 bulk samples of construction aggregates for gravel production were collected in a quarry in the Pilsen-Litice district. The quarry is the largest quarry in the Pilsen region and the closest quarry to the built-up urban area. X-ray diffraction of the asbestos minerals revealed that monoclinic amphibole (MA, namely actinolite based on subsequent SEM-EDX analysis) in the bulk samples accounted for < 1-33% of the mass and that the highest values were found in the bulk dust samples from the railway platform of the Pilsen main railway station. Simultaneously, 24-h samples of airborne particulate matter (PM) at three localities in Pilsen were collected. Actinolite was identified in 40% of the PM samples. The relationship between the meteorology and presence of actinolite in the 24 PM10 samples was not proven, probably due to the long sampling integration time. Therefore, highly time-and-size-resolved PM sampling was performed. Second, sampling of size-segregated aerosols and measurements of the wind speed (WS), wind direction (WD), precipitation (P) and hourly PM10, PM2.5 and PM1 were conducted in a suburban locality near the quarry in two monthly highly time-resolved periods (30, 60, 120 min). Three/eight PM size fractions were sampled by a Davis Rotating-drum Uniform-size-cut Monitor (3/8DRUM) and analysed for the presences of asbestos fibres by scanning electron microscopy with energy dispersive x-ray spectroscopy (SEM-EDX). Asbestos fibre detection in highly time-resolved PM samples and current WD and WS determination allows the apportionment directionality of asbestos fibre sources. The number of critical actinolite asbestos fibres (length ≥ 5 µm and width < 3 µm, 3:1) increased with the PM1-10/PM10 and PM2.5-10/PM10 ratios, WS > 2 m s-1 and precipitation < 1 mm. Additionally, the number of critical actinolite asbestos fibres was not related to a specific WD. Therefore, we conclude that the sources of airborne critical actinolite asbestos fibres in Pilsen's urban area are omnipresent. Frequent use of construction aggregates and gravel from the metamorphic spilite quarries in the Pilsen region and in many localities around the urban area is a plausible explanation for the omnipresence of the critical actinolite asbestos fibres concentration in Pilsen's ambient air. Mitigation strategies to reduce the concentrations of critical actinolite asbestos fibres must be developed. Continuous monitoring and performing SEM-EDX analysis of highly time-and-size-resolved PM samples, correlated with fast changing WS and WD, seems to be a strong tool for efficiently controlling the mitigation strategies of critical actinolite asbestos fibres.


Assuntos
Poluentes Atmosféricos/análise , Amianto/química , Monitoramento Ambiental/métodos , Material Particulado/química , Aerossóis/análise , Poluição do Ar , República Tcheca , Poeira/análise , Microscopia Eletrônica de Varredura , Tamanho da Partícula
5.
PLoS One ; 11(10): e0162978, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27711187

RESUMO

Glioblastoma multiforme (GBM) is the most common and aggressive primary intracranial brain tumor in adults with a mean survival of 14 to 15 months. Aberrant activation of the epidermal growth factor receptor (EGFR) plays a significant role in GBM progression, with amplification or overexpression of EGFR in 60% of GBM tumors. To target EGFR expressed by GBM, we have developed a strategy to deliver the coding sequence for cetuximab, an anti-EGFR antibody, directly to the CNS using an adeno-associated virus serotype rh.10 gene transfer vector. The data demonstrates that single, local delivery of an anti-EGFR antibody by an AAVrh.10 vector coding for cetuximab (AAVrh.10Cetmab) reduces GBM tumor growth and increases survival in xenograft mouse models of a human GBM EGFR-expressing cell line and patient-derived GBM. AAVrh10.CetMab-treated mice displayed a reduction in cachexia, a significant decrease in tumor volume and a prolonged survival following therapy. Adeno-associated-directed delivery of a gene encoding a therapeutic anti-EGFR monoclonal antibody may be an effective strategy to treat GBM.


Assuntos
Cetuximab/genética , Cetuximab/imunologia , Receptores ErbB/imunologia , Terapia Genética/métodos , Glioblastoma/genética , Glioblastoma/terapia , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Transformação Celular Neoplásica , Cetuximab/uso terapêutico , Dependovirus/genética , Regulação Neoplásica da Expressão Gênica/genética , Vetores Genéticos/genética , Glioblastoma/patologia , Humanos , Masculino , Camundongos , Análise de Sobrevida
6.
Cancer Gene Ther ; 22(1): 1-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25501993

RESUMO

The median survival of glioblastoma multiforme (GBM) is approximately 1 year. Following surgical removal, systemic therapies are limited by the blood-brain barrier. To circumvent this, we developed a method to modify neurons with the genetic sequence for therapeutic monoclonal antibodies using adeno-associated virus (AAV) gene transfer vectors, directing persistent, local expression in the tumor milieu. The human U87MG GBM cell line or patient-derived early passage GBM cells were administered to the striatum of NOD/SCID immunodeficient mice. AAVrh.10BevMab, an AAVrh.10-based vector coding for bevacizumab (Avastin), an anti-human vascular endothelial growth factor (VEGF) monoclonal antibody, was delivered to the area of the GBM xenograft. Localized expression of bevacizumab was demonstrated by quantitative PCR, ELISA and western blotting. Immunohistochemistry showed that bevacizumab was expressed in neurons. Concurrent administration of AAVrh.10BevMab with the U87MG tumor reduced tumor blood vessel density and tumor volume, and increased survival. Administration of AAVrh.10BevMab 1 week after U87MG xenograft reduced growth and increased survival. Studies with patient-derived early passage GBM primary cells showed a reduction in primary tumor burden with an increased survival. These data support the strategy of AAV-mediated central nervous system gene therapy to treat GBM, overcoming the blood-brain barrier through local, persistent delivery of an anti-angiogenesis monoclonal antibody.


Assuntos
Anticorpos Monoclonais Humanizados/genética , Expressão Gênica , Glioblastoma/genética , Glioblastoma/terapia , Neovascularização Patológica/terapia , Neurônios/metabolismo , Animais , Bevacizumab , Encéfalo/metabolismo , Encéfalo/patologia , Dependovirus/genética , Modelos Animais de Doenças , Feminino , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Glioblastoma/mortalidade , Glioblastoma/patologia , Humanos , Imageamento por Ressonância Magnética , Camundongos , Transdução Genética , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Chemphyschem ; 15(6): 1056-61, 2014 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-24616264

RESUMO

Compact, thin TiO2 films are grown on F-doped SnO2 (FTO) by dip-coating from precursor solutions containing poly(hexafluorobutyl methacrylate) or hexafluorobutyl methacrylate as the structure-directing agents. The films are quasi-amorphous, but crystallize to TiO2 (anatase) upon heat treatment at 500 °C in air. Cyclic voltammetry experiments performed using Fe(CN)6(3-/4-) or spiro-OMeTAD as model redox probes selectively indicate the pinholes, if any, in the layer. The pinhole-free films on FTO represent an excellent rectifying interface at which no anodic faradaic reactions occur in the depletion state. The flat-band potentials of the as-grown films are upshifted by 0.2-0.4 V against the values predicted for a perfect anatase single-crystal surface, but they still follow the Nernstian pH dependence. The optimized buffer layer is characterized by a combination of quasi-amorphous morphology (which is responsible for the blocking function) and calcination-induced crystallinity (which leads to fast electron injection and electron transport in the conduction band). The latter manifests itself by a reversible charging of the chemical capacitance of TiO2 in its accumulation state. The capacitive-charging capability and pinhole formation significantly depend on the post-deposition heat treatment.

8.
Acta Crystallogr C ; 68(Pt 2): o57-60, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22307254

RESUMO

The triclinic structure of the title compound, C(6)H(8)N(+)·H(2)PO(4)(-), with three symmetry-independent structural units (Z' = 3), is formed of separate organic and inorganic layers alternating along the b axis. The building blocks of the inorganic layer are deformed H(2)PO(4) tetrahedra assembled into infinite ladders by short and hence strong hydrogen bonds. The anilinium cations forming the organic layer are not hydrogen bonded to one another, but they are anchored by four N-H···O crosslinks between the dihydrogen phosphate chains of adjacent ladders. Two H atoms of each -NH(3) group then form one normal and one bifurcated N-H···O hydrogen bond to the P=O oxygens of two tetrahedra of one chain, while the third H atom is hydrogen bonded to the nearest O atom of an adjacent chain belonging to another dihydrogen phosphate ladder.


Assuntos
Compostos de Anilina/química , Cátions/química , Fosfatos/química , Cristalografia por Raios X , Ligação de Hidrogênio , Estrutura Molecular
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