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1.
Int J Radiat Oncol Biol Phys ; 97(4): 786-796, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28244415

RESUMO

PURPOSE: Randomized trials have shown that honey is effective for the prevention of radiation-induced mucositis in head and neck cancer patients. Because there is no efficacious preventative for radiation esophagitis in lung cancer patients, this trial compared liquid honey, honey lozenges, and standard supportive care for radiation esophagitis. METHODS: The patients were stratified by percentage of esophagus receiving specific radiation dose (V60 Gy esophagus <30% or ≥30%) and were then randomized between supportive care, 10 mL of liquid manuka honey 4 times a day, and 2 lozenges (10 mL of dehydrated manuka honey) 4 times a day during concurrent chemotherapy and radiation therapy. The primary endpoint was patient-reported pain on swallowing, with the use of an 11-point (0-10) scale at 4 weeks (Numerical Rating Pain Scale, NRPS). The study was designed to detect a 15% relative reduction of change in NRPS score. The secondary endpoints were trend of pain over time, opioid use, clinically graded and patient-reported adverse events, weight loss, dysphagia, nutritional status, and quality of life. RESULTS: 53 patients were randomized to supportive care, 54 were randomized to liquid honey, and 56 were randomized to lozenge honey. There was no significant difference in the primary endpoint of change in the NRPS at 4 weeks between arms. There were no differences in any of the secondary endpoints except for opioid use at 4 weeks during treatment between the supportive care and liquid honey arms, which was found to be significant (P=.03), with more patients on the supportive care arm taking opioids. CONCLUSION: Honey as prescribed within this protocol was not superior to best supportive care in preventing radiation esophagitis. Further testing of other types of honey and research into the mechanisms of action are needed.


Assuntos
Quimiorradioterapia/efeitos adversos , Dietoterapia/métodos , Esofagite/prevenção & controle , Mel , Neoplasias Pulmonares/radioterapia , Lesões por Radiação/prevenção & controle , Idoso , Esofagite/etiologia , Feminino , Humanos , Leptospermum , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/etiologia , Resultado do Tratamento
2.
Radiat Oncol ; 12(1): 35, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28143558

RESUMO

OBJECTIVES: To report overall survival and local control for patients identified in the RSSearch® Patient Registry with metastatic cancer to the lung treated with SBRT. METHODS: Seven hundred two patients were identified with lung metastases in the RSSearch® Registry. Of these patients, 577 patients had SBRT dose and fractionation information available. Patients were excluded if they received prior surgery, radiation, or radiofrequency ablation to the SBRT treated area. Between April 2004-July 2015, 447 patients treated with SBRT at 30 academic and community-based centers were evaluable for overall survival (OS). Three hundred four patients with 327 lesions were evaluable for local control (LC). All doses were converted to Monte Carlo equivalents and subsequent BED Gy10 for dose response analysis. RESULTS: Median age was 69 years (range, 18-93 years). Median Karnofsky performance status (KPS) was 90 (range 25/75% 80-100). 49.2% of patients had prior systemic therapy. Median metastasis volume was 10.58 cc (range 25/75% 3.7-25.54 cc). Site of primary tumor included colorectal (25.7%), lung (16.6%), head and neck (11.4%), breast (9.2%), kidney (8.1%), skin (6.5%) and other (22.1%). Median dose was 50 Gy (range 25/75% 48-54) delivered in 3 fractions (range 25/75% 3-5) with a median BED of 100Gy10 (range 25/75% 81-136). Median OS for the entire group was 26 months, with actuarial 1-, 3-, and 5-year OS of 74.1%, 33.3, and 21.8%, respectively. Patients with head and neck and breast cancers had longer median OS of 37 and 32 months respectively, compared to colorectal (30 months) and lung (26 months) which corresponded to 3-year actuarial OS of 51.8 and 47.9% for head and neck and breast respectively, compared to 35.8% for colorectal and 31.2% for lung. The median LC for all patients was 53 months, with actuarial 1-, 3-, and 5-year LC rates of 80.4, 58.9, and 46.3%, respectively. There was no difference in LC by primary histologic type (p = 0.49). Improved LC was observed for lung metastases that received SBRT doses of BED ≥100Gy10 with 3-year LC rate of 77.1% compared to 45% for lung metastases treated with BED < 100Gy10 (p = 0.01). Smaller tumor volumes (<11 cc) had improved LC compared to tumor volumes > 11 cc. (p = 0.005) Two-year LC rates for tumor volumes < 11 cc, 11-27 cc and > 27 cc were 72.9, 64.2 and 45.6%, respectively. This correlated with improved OS with 2-year OS rates of 62.4, 60.9 and 46.2% for tumor volumes < 11 cc, 11-27 cc and > 27 cc, respectively (p = 0.0023). In a subset of patients who received BED ≥100Gy10, 2-year LC rates for tumor volumes < 11 cc, 11-27 cc and > 27 cc were 82.8, 58.9 and 68.6%, respectively (p = 0.0244), and 2-year OS rates were 66.0, 58.8 and 28.5%, respectively (p = 0.0081). CONCLUSION: Excellent OS and LC is achievable with SBRT utilizing BED ≥100Gy10 for lung metastases according to the RSSearch® Registry data. Patients with small lung metastases (volumes < 11 cc) had better LC and OS when using SBRT doses of BED ≥100Gy10. Further studies to evaluate a difference, if any, between various tumor types will require a larger number of patients.


Assuntos
Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/cirurgia , Radiocirurgia , Sistema de Registros/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Dosagem Radioterapêutica , Taxa de Sobrevida , Adulto Jovem
3.
Radiat Oncol ; 10: 113, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25975848

RESUMO

BACKGROUND: The purpose of this study was to evaluate treatment patterns and outcomes of stereotactic body radiotherapy (SBRT) for centrally located primary non-small cell lung cancer (NSCLC) or lung metastases from the RSSearch(®) Patient Registry, an international, multi-center patient registry dedicated to radiosurgery and SBRT. METHODS: Eligible patients included those with centrally located lung tumors clinically staged T1-T2 N0, M0, biopsy-confirmed NSCLC or lung metastases treated with SBRT between November 2004 and January 2014. Descriptive analysis was used to report patient demographics and treatment patterns. Overall survival (OS) and local control (LC) were determined using Kaplan-Meier method. Toxicity was reported using the Common Terminology Criteria for Adverse Events version 3.0. RESULTS: In total, 111 patients with 114 centrally located lung tumors (48 T1-T2,N0,M0 NSCLC and 66 lung metastases) were treated with SBRT at 19 academic and community-based radiotherapy centers in the US and Germany. Median follow-up was 17 months (range, 1-72). Median age was 74 years for primary NSCLC patients and 65 years for lung metastases patients (p < 0.001). SBRT dose varied from 16 - 60 Gy (median 48 Gy) delivered in 1-5 fractions (median 4 fractions). Median dose to centrally located primary NSCLC was 48 Gy compared to 37.5 Gy for lung metastases (p = 0.0001) and median BED10 was 105.6 Gy for primary NSCLC and 93.6 Gy for lung metastases (p = 0.0005). Two-year OS for T1N0M0 and T2N0M0 NSCLC was 79 and 32.1 %, respectively (p = 0.009) and 2-year OS for lung metastases was 49.6 %. Two-year LC was 76.4 and 69.8 % for primary NSCLC and lung metastases, respectively. Toxicity was low with no Grade 3 or higher acute or late toxicities. CONCLUSION: Overall, patients with centrally located primary NSCLC were older and received higher doses of SBRT than those with lung metastases. Despite these differences, LC and OS was favorable for patients with central lung tumors treated with SBRT. Reported toxicity was low, although low grade toxicities were observed in patients where dose tolerances approached or exceeded published guidelines. Prospective studies are needed to further define the optimal SBRT dose for this cohort of patients. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT01885299.


Assuntos
Adenocarcinoma/cirurgia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Pulmonares/cirurgia , Recidiva Local de Neoplasia/cirurgia , Radiocirurgia/mortalidade , Sistema de Registros , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/secundário , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Dosagem Radioterapêutica , Estudos Retrospectivos , Taxa de Sobrevida
4.
J Radiat Oncol ; 4(1): 55-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25774243

RESUMO

OBJECTIVES: Stereotactic body radiotherapy (SBRT) is a definitive local treatment option for patients with stage I non-small cell lung cancer (NSCLC) who are not surgical candidates and patients who refuse surgery. The purpose of this study was to assess the impact of SBRT on T1-T2 NSCLC from a national registry, reflecting practices and outcomes in a real-world setting. METHODS: The RSSearch® Patient Registry was screened for T1-T2N0M0 NSCLC patients treated from May 2004 to May 2013 with SBRT. Descriptive analyses were used for patient, tumor, and treatment characteristics. Overall survival (OS) and local control (LC) were calculated using the Kaplan-Meier method. RESULTS: In total, 723 patients with 517 T1 and 224 T2 lesions were treated with SBRT. Median follow-up was 12 months (1-87 months) with a median age of 76 years. Median SBRT dose was 54 Gy (range 10-80 Gy) delivered in a median of 3 fractions (range 1-5), and median biological equivalent dose (BED10) was 151.2 Gy (range 20-240 Gy). Median OS was 30 and 26 months for T1 and T2 tumors, respectively (p = 0.019). LC was associated with higher BED10 for T2 tumors, but not in T1 tumors at a median follow-up of 17 months. Seventeen-month LC for T2 tumors treated with BED10 < 105 Gy, BED10 105-149, and BED10 ≥ 150 Gy was 43, 74, and 95 %, respectively (p = 0.011). Local failure rates for T2 tumors treated with BED10 < 105 Gy, 105-149 Gy, and ≥150 Gy were 32, 21, and 8 % (p = 0.029), respectively. Median OS for patients with T2 tumors treated with BED10 < 105 Gy was 17 vs. 32 months for T2 tumors treated with BED10 105-149 Gy (p = 0.062). CONCLUSION: SBRT for T1-T2 NSCLC is feasible and effective in the community setting. OS was greater for patients with T1 lesions compared to T2 lesions. An improvement in LC was observed in patients with T2 lesions treated with BED10 > 105 Gy.

5.
Mar Drugs ; 10(2): 509-520, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22412816

RESUMO

Sharks are among the most threatened groups of marine species. Populations are declining globally to support the growing demand for shark fin soup. Sharks are known to bioaccumulate toxins that may pose health risks to consumers of shark products. The feeding habits of sharks are varied, including fish, mammals, crustaceans and plankton. The cyanobacterial neurotoxin ß-N-methylamino-L-alanine (BMAA) has been detected in species of free-living marine cyanobacteria and may bioaccumulate in the marine food web. In this study, we sampled fin clips from seven different species of sharks in South Florida to survey the occurrence of BMAA using HPLC-FD and Triple Quadrupole LC/MS/MS methods. BMAA was detected in the fins of all species examined with concentrations ranging from 144 to 1836 ng/mg wet weight. Since BMAA has been linked to neurodegenerative diseases, these results may have important relevance to human health. We suggest that consumption of shark fins may increase the risk for human exposure to the cyanobacterial neurotoxin BMAA.


Assuntos
Diamino Aminoácidos/análise , Nadadeiras de Animais/química , Organismos Aquáticos/metabolismo , Toxinas Bacterianas/metabolismo , Cianobactérias/metabolismo , Neurotoxinas/metabolismo , Tubarões/crescimento & desenvolvimento , Animais , Oceano Atlântico , Toxinas de Cianobactérias , Espécies em Perigo de Extinção , Florida , Contaminação de Alimentos , Proliferação Nociva de Algas , Especificidade de Órgãos , Alimentos Marinhos/análise , Estações do Ano , Especificidade da Espécie
6.
Harmful Algae ; 9(6): 620-635, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21057660

RESUMO

Recent studies demonstrate that most cyanobacteria produce the neurotoxin beta-N-methylamino-L-alanine (BMAA) and that it can biomagnify in at least one terrestrial food chain. BMAA has been implicated as a significant environmental risk in the development of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and Amyotrophic Lateral Sclerosis (ALS). We examined several blooms of cyanobacteria in South Florida, and the BMAA content of resident animals, including species used as human food. A wide range of BMAA concentrations were found, ranging from below assay detection limits to approximately 7000 µg/g, a concentration associated with a potential long-term human health hazard.

7.
Forensic Sci Int ; 190(1-3): e13-9, 2009 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-19541436

RESUMO

Excited delirium (ED) syndrome is a serious medical condition associated with acute onset of agitated violent behavior that often culminates in a sudden unexplained death. While the contribution of restraint, struggle and the use of conductive energy devices (CED) to the cause and manner of death raise controversy, a CNS dysfunction of dopamine signaling may underlie the delirium and fatal autonomic dysfunction. We conducted a mortality review for a case series of ninety excited delirium deaths and present results on the association of a 2-protein biomarker signature. We conducted quantitative analyses of the dopamine transporter and heat shock protein 70 validated for specificity and degree of interindividual variation. Incident circumstances, force measures, autopsy and toxicology results were determined for all subjects. A majority of the victims in this case series tested positive for cocaine in blood and brain, although four had no licit or illicit drugs or alcohol measured at autopsy. Mean core body temperature where recorded was 40.7 degrees C. The expression of the heat shock protein HSPA1B transcript was elevated 1.8-4-fold in postmortem brain. The elevation of Hsp70 in autopsy brain specimens confirms that hyperthermia is an associated symptom and often a harbinger of death in these cases. Dopamine transporter levels were below the range of values measured in age-matched controls, providing pathologic evidence for increased risk of chaotic dopamine signaling in excited delirium. When combined with descriptions of the decedents' behavior prior to death, a 2-protein biomarker signature can serve as a reliable forensic tool for identifying the excited delirium syndrome at autopsy.


Assuntos
Encéfalo/metabolismo , Morte Súbita/etiologia , Delírio/diagnóstico , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Adulto , Anfetaminas/análise , Biomarcadores/metabolismo , Western Blotting , Química Encefálica , Estudos de Casos e Controles , Cocaína/análogos & derivados , Cocaína/análise , Delírio/metabolismo , Delírio/psicologia , Inibidores da Captação de Dopamina/análise , Feminino , Genética Forense , Patologia Legal , Proteínas de Choque Térmico HSP70/genética , Humanos , Masculino , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Transcrição Gênica , Violência/psicologia
8.
Drug Alcohol Depend ; 94(1-3): 246-50, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18055133

RESUMO

Alpha synuclein is increased in dopamine neurons of cocaine abusers and in rats whose alcohol preference is inbred. Recent studies have shown increased alpha synuclein protein expression in serum of alcoholic patients that is linked with severity of alcohol craving. The aim of this study was to analyze the serum levels of alpha synuclein in healthy subjects and in recently abstinent cocaine abusers. Alpha synuclein protein expression was measured by enzyme-linked immunosorbent assay in serum specimens obtained from 38 recently abstinent cocaine dependent patients and 14 control subjects. The presence of cocaine dependence disorder was based on the Structured Clinical Interview (DSM-IV). Drug severity was assessed by the Addiction Severity Index ratings and composite measures. Scores of the intensity and frequency of cocaine craving episodes were obtained from the Minnesota Cocaine Craving Questionnaire. The serum concentrations of alpha synuclein in cocaine dependent patients were significantly higher as compared with age-matched drug-free controls (p<0.001). Alpha synuclein levels in blood were significantly correlated with the intensity (r=0.60, p<0.001) and frequency (r=0.64, p<0.001) of cocaine craving and with 30 days of cocaine use in the prior month before entry to treatment (r=0.56, p<0.005). However, there was no correlation between the serum protein levels of alpha synuclein and age in either group. This report is the first demonstration of altered alpha synuclein levels in peripheral blood from cocaine abusers. These data agree with previous reports in postmortem brain of cocaine abusers and provide support for an association between alpha synuclein and cocaine dependence.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/sangue , alfa-Sinucleína/sangue , Adulto , Transtornos Disruptivos, de Controle do Impulso e da Conduta/diagnóstico , Transtornos Disruptivos, de Controle do Impulso e da Conduta/epidemiologia , Dopamina/metabolismo , Feminino , Humanos , Entrevista Psicológica , Masculino , Programas de Rastreamento/métodos , Inquéritos e Questionários , alfa-Sinucleína/metabolismo
9.
PLoS One ; 2(11): e1187, 2007 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-18000554

RESUMO

The chronic effects of cocaine abuse on brain structure and function are blamed for the inability of most addicts to remain abstinent. Part of the difficulty in preventing relapse is the persisting memory of the intense euphoria or cocaine "rush". Most abused drugs and alcohol induce neuroplastic changes in brain pathways subserving emotion and cognition. Such changes may account for the consolidation and structural reconfiguration of synaptic connections with exposure to cocaine. Adaptive hippocampal plasticity could be related to specific patterns of gene expression with chronic cocaine abuse. Here, we compare gene expression profiles in the human hippocampus from cocaine addicts and age-matched drug-free control subjects. Cocaine abusers had 151 gene transcripts upregulated, while 91 gene transcripts were downregulated. Topping the list of cocaine-regulated transcripts was RECK in the human hippocampus (FC = 2.0; p<0.05). RECK is a membrane-anchored MMP inhibitor that is implicated in the coordinated regulation of extracellular matrix integrity and angiogenesis. In keeping with elevated RECK expression, active MMP9 protein levels were decreased in the hippocampus from cocaine abusers. Pathway analysis identified other genes regulated by cocaine that code for proteins involved in the remodeling of the cytomatrix and synaptic connections and the inhibition of blood vessel proliferation (PCDH8, LAMB1, ITGB6, CTGF and EphB4). The observed microarray phenotype in the human hippocampus identified RECK and other region-specific genes that may promote long-lasting structural changes with repeated cocaine abuse. Extracellular matrix remodeling in the hippocampus may be a persisting effect of chronic abuse that contributes to the compulsive and relapsing nature of cocaine addiction.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/genética , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica , Hipocampo/metabolismo , Adulto , Regulação para Baixo , Feminino , Humanos , Masculino , Metaloproteinase 9 da Matriz/genética , Análise de Sequência com Séries de Oligonucleotídeos
10.
Gene Expr ; 13(3): 205-15, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17193926

RESUMO

Combining large-scale gene expression approaches and bioinformatics may provide insights into the molecular variability of biological processes underlying neurodegeneration. To identify novel candidate genes and mechanisms, we conducted a multiregional gene expression analysis in postmortem brain. Gene arrays were performed utilizing Affymetrix HG U133 Plus 2.0 gene chips. Brain specimens from 21 different brain regions were taken from Parkinson's disease (PD) (n = 22) and normal aged (n = 23) brain donors. The rationale for conducting a multiregional survey of gene expression changes was based on the assumption that if a gene is changed in more than one brain region, it may be a higher probability candidate gene compared to genes that are changed in a single region. Although no gene was significantly changed in all of the 21 brain regions surveyed, we identified 11 candidate genes whose pattern of expression was regulated in at least 18 out of 21 regions. The expression of a gene encoding the mitochondria ribosomal protein S6 (MRPS6) had the highest combined mean fold change and topped the list of regulated genes. The analysis revealed other genes related to apoptosis, cell signaling, and cell cycle that may be of importance to disease pathophysiology. High throughput gene expression is an emerging technology for molecular target discovery in neurological and psychiatric disorders. The top gene reported here is the nuclear encoded MRPS6, a building block of the human mitoribosome of the oxidative phosphorylation system (OXPHOS). Impairments in mitochondrial OXPHOS have been linked to the pathogenesis of PD.


Assuntos
Biomarcadores/metabolismo , Regulação da Expressão Gênica , Proteínas Mitocondriais/genética , Doença de Parkinson/genética , Proteína S6 Ribossômica/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Mitocondriais/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação Oxidativa , RNA Mensageiro/metabolismo , Proteína S6 Ribossômica/metabolismo , Substância Negra/metabolismo
11.
Neuroreport ; 16(13): 1489-93, 2005 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-16110277

RESUMO

Direct protein interactions between the dopamine transporter and alpha-synuclein demonstrate that dopamine uptake function is modulated by alpha-synuclein. We report here that chronic cocaine abuse results in an increase in alpha-synuclein expression in the human striatum. Immunoblot analysis in the ventral putamen showed that alpha-synuclein protein was increased in striatal synaptosomes from cocaine users compared with age-matched drug-free controls. [H]-Dopamine transporter uptake was increased in parallel with 2beta-carbomethoxy-3beta-(4-fluorophenyl)tropane binding to the dopamine transporter. The increase in alpha-synuclein protein was more marked in the ventromedial sectors of the striatum than in the dorsal caudate nucleus. These results demonstrate concomitant regulation of alpha-synuclein and dopamine transporter binding and function in human striatal synaptic terminals isolated from cocaine abusers. Overexpression of alpha-synuclein may play a role in cocaine-induced plasticity and regulation of dopamine synaptic tone.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/metabolismo , Corpo Estriado/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Doença Crônica , Dopamina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina , Homeostase/efeitos dos fármacos , Humanos , Terminações Pré-Sinápticas/metabolismo , Sinucleínas , alfa-Sinucleína
12.
J Neurosci Methods ; 143(1): 79-85, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15763139

RESUMO

The norepinephrine transporter (NET) is a membrane protein responsible for transporting extracellular norepinephrine. The cocaine and tricyclic antidepressant-sensitive NET belongs to a family of sodium and chloride coupled transporters that include the monoamines dopamine and serotonin and the amino acids GABA and glycine. The regional distribution of the NET has been defined by synaptosomal uptake of norepinephrine and by autoradiographic approaches in rodent and primate brain. However, the NET has not been well characterized in the human brain due to the overall low abundance of protein expressed in axon terminals. Recently, immunolocalization studies have been used to identify the regional distribution of the cytoplasmic NET epitope in rodent brain. We report here on the characteristics of drug interactions with the native NET protein in human postmortem brain. Antisera raised against a 17-amino acid peptide from the N-terminus of the hNET recognized an 80 kDa species in human cerebral cortex. Chronic exposure to cocaine upregulated NET protein expression and [3H]nisoxetine binding sites in the insular cortex from brains of cocaine addicts. These results demonstrate that immunologic and radioligand binding approaches afford specific labeling of the native transport protein in postmortem human brain.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/metabolismo , Cocaína/farmacologia , Fluoxetina/análogos & derivados , Immunoblotting/métodos , Ensaio Radioligante/métodos , Simportadores/análise , Simportadores/efeitos dos fármacos , Anticorpos/química , Anticorpos/imunologia , Especificidade de Anticorpos/imunologia , Sítios de Ligação/efeitos dos fármacos , Sítios de Ligação/fisiologia , Ligação Competitiva/efeitos dos fármacos , Ligação Competitiva/fisiologia , Química Encefálica/efeitos dos fármacos , Química Encefálica/fisiologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Inibidores da Captação de Dopamina/farmacologia , Fluoxetina/metabolismo , Fluoxetina/farmacocinética , Humanos , Norepinefrina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Norepinefrina , Simportadores/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia
13.
J Neurosci ; 23(7): 2564-71, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12684441

RESUMO

Alpha-synuclein is a presynaptic protein that has been implicated as a possible causative agent in the pathogenesis of Parkinson's disease. The native protein is a major component of nigral Lewy bodies in Parkinson's disease, and full-length alpha-synuclein accumulates in Lewy neurites. Here we present evidence that alpha-synuclein levels are elevated in midbrain dopamine (DA) neurons of chronic cocaine abusers. Western blot and immunoautoradiographic studies were conducted on postmortem neuropathological specimens from cocaine users and age-matched drug-free control subjects. The results demonstrated that alpha-synuclein levels in the DA cell groups of the substantia nigra/ventral tegmental complex were elevated threefold in chronic cocaine users compared with normal age-matched subjects. The increased protein levels in chronic cocaine users were accompanied by changes in the expression of alpha-synuclein mRNA in the substantia nigra and ventral tegmental area. Although alpha-synuclein expression is prominent in the hippocampus, there was no increase in protein expression in this brain region. The levels of beta-synuclein, a possible negative regulator of alpha-synuclein, also were not affected by cocaine exposure. Alpha-synuclein protein levels were increased in the ventral tegmental area, but not the substantia nigra, in victims of excited cocaine delirium who experienced paranoia, marked agitation, and hyperthermia before death. The overexpression of alpha-synuclein may occur as a protective response to changes in DA turnover and increased oxidative stress resulting from cocaine abuse. However, the accumulation of alpha-synuclein protein with long-term cocaine abuse may put addicts at increased risk for developing the motor abnormalities of Parkinson's disease.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/metabolismo , Dopamina/análise , Proteínas do Tecido Nervoso/biossíntese , Neurônios/metabolismo , Western Blotting , Transtornos Relacionados ao Uso de Cocaína/genética , Regulação da Expressão Gênica , Humanos , Mesencéfalo/citologia , Mesencéfalo/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/imunologia , Neurônios/química , RNA Mensageiro/biossíntese , Sinucleínas , Transcrição Gênica , alfa-Sinucleína , beta-Sinucleína
14.
J Neurochem ; 81(2): 292-300, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12064476

RESUMO

Dopaminergic transmission has been suggested to be a primary mechanism mediating reinforcement, withdrawal and craving associated with psychostimulant addiction. Pyscho-stimulants attenuate dopamine transporter (DAT) clearance efficiency, resulting in a net increase in synaptic dopamine levels. Re-uptake rate is determined by the number of functional DAT molecules at the membrane surface. Previous in vivo imaging studies in humans and in vitro studies in post-mortem human brain have demonstrated that chronic cocaine abuse results in a neuroadaptive increase in DAT-binding site density in the limbic striatum. Whether this increase in DAT availability represents an increase in the functional activity of the transporter is unknown. Here, we present evidence that DAT function is elevated by chronic cocaine abuse. The effect of increasing post-mortem interval on the functional viability of synaptosomes was modeled in the baboon brain. Baboon brains sampled under conditions similar to human brain autopsies yielded synaptosomal preparations that were viable up to 24 h post-mortem. Dopamine (DA) uptake was elevated twofold in the ventral striatum from cocaine users as compared to age-matched drug-free control subjects. The levels of [3H]DA uptake were not elevated in victims of excited cocaine delirium, who experienced paranoia and marked agitation prior to death. In keeping with the increase in DAT function, [3H]WIN 35,428 binding was increased in the cocaine users, but not in the victims of excited delirium. These results demonstrate that DA uptake function assayed in cryopreserved human brain synaptosomes is a suitable approach for testing hypotheses of the mechanisms underlying human brain disorders and for studying the actions of addictive drugs in man.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/metabolismo , Cocaína/análogos & derivados , Glicoproteínas de Membrana , Proteínas de Membrana Transportadoras/metabolismo , Proteínas do Tecido Nervoso , Adulto , Animais , Ligação Competitiva , Encéfalo/metabolismo , Química Encefálica , Núcleo Caudado/metabolismo , Doença Crônica , Cocaína/efeitos adversos , Cocaína/sangue , Cocaína/farmacologia , Cocaína/urina , Transtornos Relacionados ao Uso de Cocaína/complicações , Corpo Estriado/metabolismo , Criopreservação , Delírio/etiologia , Delírio/metabolismo , Dopamina/farmacocinética , Proteínas da Membrana Plasmática de Transporte de Dopamina , Feminino , Humanos , Masculino , Papio , Mudanças Depois da Morte , Sinaptossomos/química , Sinaptossomos/metabolismo , Fatores de Tempo
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