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1.
Nat Commun ; 12(1): 2626, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976179

RESUMO

By conferring systemic protection and durable benefits, cancer immunotherapies are emerging as long-term solutions for cancer treatment. One such approach that is currently undergoing clinical testing is a therapeutic anti-cancer vaccine that uses two different viruses expressing the same tumor antigen to prime and boost anti-tumor immunity. By providing the additional advantage of directly killing cancer cells, oncolytic viruses (OVs) constitute ideal platforms for such treatment strategy. However, given that the targeted tumor antigen is encoded into the viral genomes, its production requires robust infection and therefore, the vaccination efficiency partially depends on the unpredictable and highly variable intrinsic sensitivity of each tumor to OV infection. In this study, we demonstrate that anti-cancer vaccination using OVs (Adenovirus (Ad), Maraba virus (MRB), Vesicular stomatitis virus (VSV) and Vaccinia virus (VV)) co-administered with antigenic peptides is as efficient as antigen-engineered OVs and does not depend on viral replication. Our strategy is particularly attractive for personalized anti-cancer vaccines targeting patient-specific mutations. We suggest that the use of OVs as adjuvant platforms for therapeutic anti-cancer vaccination warrants testing for cancer treatment.


Assuntos
Antígenos de Neoplasias/administração & dosagem , Vacinas Anticâncer/administração & dosagem , Neoplasias/terapia , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Neoplasias/imunologia , Vírus Oncolíticos/genética , Poli I-C/administração & dosagem , Poli I-C/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/genética , Vacinas de Subunidades Antigênicas/imunologia , Vaccinia virus , Vírus da Estomatite Vesicular Indiana , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Psychol Trauma ; 13(1): 104-113, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32378925

RESUMO

OBJECTIVE: Youth who receive services in residential programs have high rates of traumatic exposure and associated symptoms of Posttraumatic Stress Disorder (PTSD). Little information is available on specific social skills training that could be beneficial for youth in residential programs with PTSD. This study examined changes in behavioral incidents and psychopathology in youth receiving group home services based on training they received across three categories of social skills (i.e., self-advocacy, emotional regulation, problem-solving). METHOD: The sample included archival data on youth (N = 677) ages 10-18 years (M = 15.7 years, SD = 1.53). Hierarchical Linear Modeling was used to examine the frequency of disruptive and self-injurious behaviors over 12 months as it relates to reported traumatic symptoms at admission and the presence of the three types of social skills objectives. Analysis of Covariance was conducted to test whether the social skill objectives differentially predicted changes in youth psychopathology from intake to discharge for youth with low and high trauma symptoms. RESULTS: Youth with high trauma symptoms who received training on problem-solving skills had significantly greater decrease in emotional problems from intake to discharge compared to youth with high trauma symptoms who did not receive problem-solving training (d = -.54). CONCLUSION: Problem-solving training could be further developed and tested to maximize the support youth with trauma symptoms receive in trauma-informed residential programs. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Tratamento Domiciliar , Habilidades Sociais , Transtornos de Estresse Pós-Traumáticos/psicologia , Adolescente , Criança , Regulação Emocional , Feminino , Humanos , Modelos Lineares , Masculino , Resolução de Problemas , Psicopatologia , Autoimagem
3.
Eval Program Plann ; 83: 101854, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32818910

RESUMO

This project explored the reliability and utility of transcription in coding qualitative data across two studies in a program evaluation context. The first study tested the method of direct audio coding, or coding audio files without transcripts, using qualitative data software. The presence and frequency of codes applied in direct audio coding and traditional transcription coding were compared and the two methods produced similar results. Direct audio coding was then employed in an evaluation study to monitor implementation and the method was found to be reliable. Implications are discussed with considerations for both researchers and practitioners.


Assuntos
Projetos de Pesquisa , Pesquisadores , Humanos , Avaliação de Programas e Projetos de Saúde , Reprodutibilidade dos Testes
4.
Clin Oncol (R Coll Radiol) ; 32(4): 250-258, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31607611

RESUMO

AIMS: Stereotactic ablative body radiotherapy doses for peripheral lung lesions caused high toxicity when used for central non-small cell lung cancer (NSCLC). To determine a safe stereotactic ablative body radiotherapy dose for central tumours, the phase I/II Radiation Therapy Oncology Group RTOG 0813 trial used 50 Gy/five fractions as a baseline. From 2013, 50 Gy/five fractions was adopted at the Beatson West of Scotland Cancer Centre for inoperable early stage central NSCLC. We report our prospectively collected toxicity and efficacy data. MATERIALS AND METHODS: Patient and treatment characteristics were obtained from electronic medical records. Tumours were classed as moderately central or ultra-central tumours using published definitions. Toxicity was assessed in a centralised follow-up clinic at 2 weeks, 6 weeks, 3 months, 6 months, 1 year and 2 years after treatment. RESULTS: Fifty patients (31 women, 19 men, median age 75.1 years) were identified with T1-2N0M0 moderately central NSCLC; one patient had both an ultra-central and a moderately central tumour. Eighty-four per cent were medically unfit for surgery. Forty per cent had biopsy-proven NSCLC and 60% were diagnosed radiologically using 18-fluorodeoxyglucose positron emission tomography/computed tomography imaging. Fifty-six per cent of patients were Eastern Cooperative Oncology Group (ECOG) performance status 2 or worse. All patients received 50 Gy/five fractions on alternate days on schedule. Two patients died within 90 days of treatment, one from a chest infection, the other cause of death was unknown. There was one episode of early grade 3 oesophagitis and one grade 3 late dyspnoea. There was no grade 4 toxicity. Over a median follow-up of 25.2 months (range 1-70 months), there were 34 deaths: 18 unrelated to cancer and 16 due to cancer recurrence. The median overall survival was 27.0 months (95% confidence interval 20.6-35.9) and cancer-specific survival was 39.8 months (95% confidence interval 28.6, not reached). CONCLUSION: This study has shown that 50 Gy/five fractions is a safe dose and fractionation for early stage inoperable moderately central NSCLC, with outcomes comparable with other series, even with patients with a poor performance status.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Radiocirurgia/métodos , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Fracionamento da Dose de Radiação , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
5.
Transl Psychiatry ; 6(9): e893, 2016 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-27648915

RESUMO

Assessing cognitive abilities in children is challenging for two primary reasons: lack of testing engagement can lead to low testing sensitivity and inherent performance variability. Here we sought to explore whether an engaging, adaptive digital cognitive platform built to look and feel like a video game would reliably measure attention-based abilities in children with and without neurodevelopmental disabilities related to a known genetic condition, 16p11.2 deletion. We assessed 20 children with 16p11.2 deletion, a genetic variation implicated in attention deficit/hyperactivity disorder and autism, as well as 16 siblings without the deletion and 75 neurotypical age-matched children. Deletion carriers showed significantly slower response times and greater response variability when compared with all non-carriers; by comparison, traditional non-adaptive selective attention assessments were unable to discriminate group differences. This phenotypic characterization highlights the potential power of administering tools that integrate adaptive psychophysical mechanics into video-game-style mechanics to achieve robust, reliable measurements.


Assuntos
Transtorno Autístico/psicologia , Transtornos Cromossômicos/psicologia , Cognição , Deficiência Intelectual/psicologia , Jogos de Vídeo , Adolescente , Atenção , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/psicologia , Estudos de Casos e Controles , Criança , Deleção Cromossômica , Cromossomos Humanos Par 16 , Feminino , Humanos , Deficiência Intelectual/genética , Masculino , Projetos Piloto , Irmãos
6.
Nature ; 533(7603): 385-9, 2016 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-27193684

RESUMO

Climate variations cause ice sheets to retreat and advance, raising or lowering sea level by metres to decametres. The basic relationship is unambiguous, but the timing, magnitude and sources of sea-level change remain unclear; in particular, the contribution of the East Antarctic Ice Sheet (EAIS) is ill defined, restricting our appreciation of potential future change. Several lines of evidence suggest possible collapse of the Totten Glacier into interior basins during past warm periods, most notably the Pliocene epoch, causing several metres of sea-level rise. However, the structure and long-term evolution of the ice sheet in this region have been understood insufficiently to constrain past ice-sheet extents. Here we show that deep ice-sheet erosion-enough to expose basement rocks-has occurred in two regions: the head of the Totten Glacier, within 150 kilometres of today's grounding line; and deep within the Sabrina Subglacial Basin, 350-550 kilometres from this grounding line. Our results, based on ICECAP aerogeophysical data, demarcate the marginal zones of two distinct quasi-stable EAIS configurations, corresponding to the 'modern-scale' ice sheet (with a marginal zone near the present ice-sheet margin) and the retreated ice sheet (with the marginal zone located far inland). The transitional region of 200-250 kilometres in width is less eroded, suggesting shorter-lived exposure to eroding conditions during repeated retreat-advance events, which are probably driven by ocean-forced instabilities. Representative ice-sheet models indicate that the global sea-level increase resulting from retreat in this sector can be up to 0.9 metres in the modern-scale configuration, and exceeds 2 metres in the retreated configuration.


Assuntos
Clima , Congelamento , Sedimentos Geológicos/análise , Camada de Gelo , Modelos Teóricos , Regiões Antárticas , Aquecimento Global/estatística & dados numéricos , Gravitação , Tecnologia de Sensoriamento Remoto , Água do Mar/análise , Fatores de Tempo
7.
Med Phys ; 41(1): 012302, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24387523

RESUMO

PURPOSE: Ultrashort echo time (UTE) MRI has been proposed as a way to produce segmented attenuation maps for PET, as it provides contrast between bone, air, and soft tissue. However, UTE sequences require samples to be acquired during rapidly changing gradient fields, which makes the resulting images prone to eddy current artifacts. In this work it is demonstrated that this can lead to misclassification of tissues in segmented attenuation maps (AC maps) and that these effects can be corrected for by measuring the true k-space trajectories using a magnetic field camera. METHODS: The k-space trajectories during a dual echo UTE sequence were measured using a dynamic magnetic field camera. UTE images were reconstructed using nominal trajectories and again using the measured trajectories. A numerical phantom was used to demonstrate the effect of reconstructing with incorrect trajectories. Images of an ovine leg phantom were reconstructed and segmented and the resulting attenuation maps were compared to a segmented map derived from a CT scan of the same phantom, using the Dice similarity measure. The feasibility of the proposed method was demonstrated in in vivo cranial imaging in five healthy volunteers. Simulated PET data were generated for one volunteer to show the impact of misclassifications on the PET reconstruction. RESULTS: Images of the numerical phantom exhibited blurring and edge artifacts on the bone-tissue and air-tissue interfaces when nominal k-space trajectories were used, leading to misclassification of soft tissue as bone and misclassification of bone as air. Images of the tissue phantom and the in vivo cranial images exhibited the same artifacts. The artifacts were greatly reduced when the measured trajectories were used. For the tissue phantom, the Dice coefficient for bone in MR relative to CT was 0.616 using the nominal trajectories and 0.814 using the measured trajectories. The Dice coefficients for soft tissue were 0.933 and 0.934 for the nominal and measured cases, respectively. For air the corresponding figures were 0.991 and 0.993. Compared to an unattenuated reference image, the mean error in simulated PET uptake in the brain was 9.16% when AC maps derived from nominal trajectories was used, with errors in the SUV max for simulated lesions in the range of 7.17%-12.19%. Corresponding figures when AC maps derived from measured trajectories were used were 0.34% (mean error) and -0.21% to +1.81% (lesions). CONCLUSIONS: Eddy current artifacts in UTE imaging can be corrected for by measuring the true k-space trajectories during a calibration scan and using them in subsequent image reconstructions. This improves the accuracy of segmented PET attenuation maps derived from UTE sequences and subsequent PET reconstruction.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Campos Magnéticos , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Crânio/diagnóstico por imagem , Humanos , Modelos Teóricos , Imagens de Fantasmas , Fatores de Tempo
8.
Clin Oncol (R Coll Radiol) ; 25(1): 66-73, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22795232

RESUMO

AIMS: To compare the accuracy of fractionated cranial radiotherapy in a standard three-point thermoplastic shell using daily online correction with accuracy in a Gill-Thomas-Cosman relocatable stereotactic frame. MATERIALS AND METHODS: All patients undergoing fractionated radiotherapy for benign intracranial tumours between March 2009 and August 2010 were included. Patients were immobilised in the frame with those unable to tolerate it immobilised in the shell. The ExacTrac imaging system was used for verification/correction. Daily online imaging before and after correction was carried out for shell patients and systematic and random population set-up errors calculated. These were compared with frame patients who underwent standard departmental imaging/correction with fractions 1-3 and weekly thereafter. Set-up margins were calculated from population errors. RESULTS: Systematic and random errors were 0.3-0.7 mm/° before correction and 0.1-0.2 mm/° after correction in all axes in the frame, and 0.6-1.5 mm/° before correction and 0.1-0.4 mm/° after correction in the shell. Isotropic margins required for patient set-up could be reduced from 2 mm to <1 mm in the frame and from 5 mm to <1 mm in the shell. CONCLUSION: Similar set-up accuracy can be achieved in the standard thermoplastic shell as in a relocatable frame despite less precise immobilisation. The use of daily online correction precludes the need for larger set-up margins.


Assuntos
Neoplasias Encefálicas/cirurgia , Radiocirurgia , Adulto , Idoso , Fracionamento da Dose de Radiação , Feminino , Humanos , Imobilização , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Dement Geriatr Cogn Dis Extra ; 3(1): 446-58, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24516412

RESUMO

BACKGROUND: Sensitive cognitive global scores are beneficial in screening and monitoring for prodromal Alzheimer's disease (AD). Early cortical changes provide a novel opportunity for validating established cognitive total scores against the biological disease markers. METHODS: We examined how two different total scores of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) battery and the Mini-Mental State Examination (MMSE) are associated with cortical thickness (CTH) in mild cognitive impairment (MCI) and prodromal AD. Cognitive and magnetic resonance imaging (MRI) data of 22 progressive MCI, 78 stable MCI, and 98 control subjects, and MRI data of 103 AD patients of the prospective multicenter study were analyzed. RESULTS: CERAD total scores correlated with mean CTH more strongly (r = 0.34-0.38, p < 0.001) than did MMSE (r = 0.19, p = 0.01). Of those vertex clusters that showed thinning in progressive MCI, 60-75% related to the CERAD total scores and 3% to the MMSE. CONCLUSION: CERAD total scores are sensitive to the CTH signature of prodromal AD, which supports their biological validity in detecting early disease-related cognitive changes.

10.
Genet Mol Res ; 11(3): 2801-13, 2012 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-23007975

RESUMO

Extracts of mistletoe (Viscum album) are intensively used in complementary medicine, but their mechanisms are not fully understood in most cases, and the effects on metabolism have not been investigated in detail. However, some biologically active natural products are well known to provoke unexpected cellular responses. They reduce overexpression of heat shock proteins (Hsps) in cancer cells. The aim of the current study was to determine whether methanolic extract of V. album, which possesses antioxidant activity, has an effect on expression levels of Hsp27 and 14-3-3 proteins in a C6 glioma cell line. For the first time, the apoptosis-inducing effect of this extract was also determined via caspase-3 activation in the cells. Overexpression of Hsps was induced by heat shock at 42°C for 1 h. Expression levels of Hsp27 and 14-3-3 proteins were determined using Western blot analysis. The apoptosis-inducing effect was also evaluated via caspase-3 activation in C6 glioma cells. Pretreatment of the cells with a nontoxic dose (100 µg/mL) of V. album extract before heat shock significantly reduced expression levels of Hsp27 (73%) and 14-3-3ß (124%), 14-3-3γ (23%), and 14-3-3ζ (84%) proteins. Pretreatment with the extract before heat shock increased apoptosis via caspase-3 activation (60%) in C6 glioma cells. This result suggested that the methanolic extract of V. album downregulates expression of Hsp27 and 14-3-3 chaperone proteins and induces apoptosis, which warrants further exploration as a potential bioactive compound for cancer therapy.


Assuntos
Proteínas 14-3-3/metabolismo , Apoptose/efeitos dos fármacos , Glioma/metabolismo , Glioma/patologia , Proteínas de Choque Térmico HSP27/metabolismo , Erva-de-Passarinho/química , Extratos Vegetais/farmacologia , Animais , Western Blotting , Linhagem Celular Tumoral , Glioma/tratamento farmacológico , Glioma/enzimologia , Metanol , Fitoterapia , Extratos Vegetais/uso terapêutico , Ratos
11.
J Gen Virol ; 86(Pt 8): 2393-2399, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16033987

RESUMO

It has now been established that transmissible spongiform encephalopathy (TSE) infectivity, which is highly resistant to conventional methods of deactivation, can be transmitted iatrogenically by contaminated stainless steel. It is important that new methods are evaluated for effective removal of protein residues from surgical instruments. Here, radio-frequency (RF) gas-plasma treatment was investigated as a method of removing both the protein debris and TSE infectivity. Stainless-steel spheres contaminated with the 263K strain of scrapie and a variety of used surgical instruments, which had been cleaned by a hospital sterile-services department, were examined both before and after treatment by RF gas plasma, using scanning electron microscopy and energy-dispersive X-ray spectroscopic analysis. Transmission of scrapie from the contaminated spheres was examined in hamsters by the peripheral route of infection. RF gas-plasma treatment effectively removed residual organic residues on reprocessed surgical instruments and gross contamination both from orthopaedic blades and from the experimentally contaminated spheres. In vivo testing showed that RF gas-plasma treatment of scrapie-infected spheres eliminated transmission of infectivity. The infectivity of the TSE agent adsorbed on metal spheres could be removed effectively by gas-plasma cleaning with argon/oxygen mixtures. This treatment can effectively remove 'stubborn' residual contamination on surgical instruments.


Assuntos
Desinfecção/métodos , Doenças Priônicas/prevenção & controle , Príons , Instrumentos Cirúrgicos , Animais , Argônio , Cricetinae , Modelos Animais de Doenças , Feminino , Gases , Oxigênio , Ondas de Rádio , Aço Inoxidável
12.
J Hosp Infect ; 56(1): 37-41, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14706269

RESUMO

The theoretical risk of prion transmission via surgical instruments is of current public and professional concern. These concerns are further heightened by reports of the strong surface affinity of the prion protein, and that the removal of organic material by conventional sterilization is often inadequate. Recent reports of contamination on sterilized endodontic files are of particular relevance given the close contact that these instruments may make with peripheral nerve tissue. In this paper, we report the effective use of a commercial gas plasma etcher in the cleaning of endodontic files. A representative sample of cleaned, sterilized, files was screened, using scanning electron microscopy and energy-dispersive X-ray analysis, to determine the level of contamination before plasma cleaning. The files were then exposed for a short-term to a low-pressure oxygen-argon plasma, before being re-examined. In all cases, the amount of organic material (in particular that which may have comprised protein) was reduced to a level below the detection limit of the instrument. This work suggests that plasma cleaning offers a safe and effective method for decontamination of dental instruments, thus reducing the risk of iatrogenic transmission of disease during dental procedures. Furthermore, whilst this study focuses on dental files, the findings indicate that the method may be readily extended to the decontamination of general surgical instruments.


Assuntos
Argônio , Descontaminação/métodos , Equipamentos Odontológicos/virologia , Gases , Oxigênio , Esterilização/métodos , Contaminação de Equipamentos , Humanos , Microscopia Eletrônica de Varredura , Doenças Priônicas/prevenção & controle , Doenças Priônicas/transmissão
13.
Br J Dermatol ; 149(6): 1227-31, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14674901

RESUMO

BACKGROUND: Optimization of ultraviolet (UV) phototherapy for treatment of psoriasis and other skin conditions requires accurate dosimetry. One factor involved in whole body treatments is the correction that needs to be applied to radiometer measurements of irradiance made remotely without a person in the phototherapy cabin. OBJECTIVES: To evaluate the correction factor for cabins of different design and to consider whether different factors should be used for different phototherapy cabins and radiometers. METHODS: An automated UV dosimetry system capable of recording irradiances at positions around the circumference of a circle equating to a human trunk has been developed. The system has been combined with a phantom to derive values for the ratio between irradiance measurements made by the direct method with a person in a cabin, and indirect measurements recorded remotely. In addition, values for the ratio in UVA cabins have been derived from comparisons between measurements made directly by persons in a cabin and indirect measurements. RESULTS: Variations in direct to indirect ratio (DIR) with cabin type were less than between individual sets of measurements. The mean DIR obtained for cabins with TL01 lamps was 0.85 +/- 0.02, while that for UVA cabins was 0.80 +/- 0.05. The DIR for dual lamp (TL01/UVA) cabins, when TL01 lamps were illuminated, was higher (0.92). CONCLUSIONS: The DIR should be applied to any measurements made using radiometers without a person or equivalent phantom in a cabin. It is proposed that standard values are appropriate for groups of cabins with a single type of lamp and similar reflectors.


Assuntos
Processamento Eletrônico de Dados , Radiometria/métodos , Raios Ultravioleta , Terapia Ultravioleta/métodos , Humanos , Imagens de Fantasmas , Psoríase/terapia , Dosagem Radioterapêutica , Terapia Ultravioleta/instrumentação
14.
Biochem Soc Trans ; 30(4): 351-60, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12196094

RESUMO

Proteins that interact with 14-3-3 isoforms are involved in regulation of the cell cycle, intracellular trafficking/targeting, signal transduction, cytoskeletal structure and transcription. Recent novel roles for 14-3-3 isoforms include nuclear trafficking the direct interaction with cruciform DNA and with a number of receptors, small G-proteins and their regulators. Recent findings also show that the mechanism of interaction is also more complex than the initial finding of the novel phosphoserine/threonine motif. Non-phosphorylated binding motifs that can also be of high affinity may show a more isoform-dependent interaction and binding of a protein through two distinct binding motifs to a dimeric 14-3-3 may also be essential for full interaction. Phosphorylation of specific 14-3-3 isoforms can also regulate interactions. In many cases, they show a distinct preference for a particular isoform(s) of 14-3-3. A specific repertoire of dimer formation may influence which of the 14-3-3-interacting proteins could be brought together. Mammalian and yeast 14-3-3 isoforms show a preference for dimerization with specific partners in vivo.


Assuntos
Encéfalo/fisiologia , Fenômenos Fisiológicos Celulares , Tirosina 3-Mono-Oxigenase/química , Tirosina 3-Mono-Oxigenase/metabolismo , Proteínas 14-3-3 , Sequência de Aminoácidos , Animais , Sítios de Ligação , Ciclo Celular/fisiologia , Dimerização , Humanos , Dados de Sequência Molecular , Fosforilação , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo
15.
Biochem Soc Trans ; 30(4): 387-91, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12196100

RESUMO

14-3-3 proteins are involved in signalling processes in neuronal cells. Using isoform-specific antibodies we have examined the variation in 14-3-3 isoform neurolocation in normal and scrapie-infected murine brain and show that in defined areas of the brain there are significant changes associated with the pathology of the disease process. The appearance of 14-3-3 proteins in the cerebrospinal fluid (CSF) is a consequence of neuronal disease and the detection of specific isoforms of the 14-3-3 proteins in the CSF is characteristic of some neurodegenerative diseases. In this study, monitoring specifically for the gamma 14-3-3 isoform in the CSF by both Western-blot analysis and ELISA we can show a level of correlation between the assays.


Assuntos
Doenças Priônicas/diagnóstico , Tirosina 3-Mono-Oxigenase/análise , Proteínas 14-3-3 , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Imuno-Histoquímica/métodos , Doenças Neurodegenerativas/líquido cefalorraquidiano , Doenças Neurodegenerativas/diagnóstico , Neurônios/enzimologia , Doenças Priônicas/líquido cefalorraquidiano , Transdução de Sinais , Tirosina 3-Mono-Oxigenase/líquido cefalorraquidiano
16.
Neuroscience ; 109(1): 5-14, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11784696

RESUMO

The appearance of 14-3-3 proteins in the cerebrospinal fluid is characteristic of some neurodegenerative conditions which include sporadic Creutzfeldt-Jakob disease. Although 14-3-3 proteins are physiochemically well characterised and are known to be present in neuronal cells little is known of the neuroanatomical localisation of the individual isoforms. Using 14-3-3 isoform specific antibodies we have examined the distribution of the isoforms in normal murine brain and the changes observed during neurodegeneration as a result of ME7 scrapie infection. In normal brain there are two major patterns of immunolabelling. The beta, gamma, eta and zeta isoforms which exhibit a similar distribution pattern showing labelling of neuronal cell bodies often in particular anatomical nuclei. However the individual isoforms exhibit variation revealing subtle differences in location. The tau isoform was found only in the hippocampus and medulla, and the epsilon isoform was found throughout grey matter of the CNS. In the scrapie-infected murine brain, where severe pathological changes occur during the course of the disease, significant differences in the 14-3-3 isoform distribution were observed in the hippocampus and in the thalamus. Importantly, both the 14-3-3 eta isoform and prion protein were seen in the same neurones in both the cerebellar roof nuclei and in the lateral hypothalamic nuclei. Our study of 14-3-3 isoform distribution in adult murine brain clearly demonstrates a heterogeneous pattern of neurolocation for specific 14-3-3 isoforms. The fact that isoform labelling in terminal scrapie CNS is lost in some brain areas, but increases in others, suggests that the processing of these proteins during neurodegeneration may be much more complex than previously recognised.


Assuntos
Encéfalo/metabolismo , Neurônios/metabolismo , Scrapie/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Proteínas 14-3-3 , Animais , Encéfalo/patologia , Encéfalo/fisiopatologia , Membrana Celular/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/patologia , Proteínas PrPSc/metabolismo , Isoformas de Proteínas/metabolismo , Scrapie/patologia , Scrapie/fisiopatologia , Serina Endopeptidases/metabolismo
17.
Biochem J ; 359(Pt 1): 55-64, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11563969

RESUMO

Mammalian chloride intracellular channel (CLIC) (p64-related) proteins are widely expressed, with an unusual dual localization as both soluble and integral membrane proteins. The molecular basis for their cellular localization and ion channel activity remains unclear. To help in addressing these problems, we identified novel rat brain CLIC4 (p64H1) binding partners by affinity chromatography, mass spectrometric analysis and microsequencing. Brain CLIC4 binds dynamin I, alpha-tubulin, beta-actin, creatine kinase and two 14-3-3 isoforms; the interactions are confirmed in vivo by immunoprecipitation. Gel overlay and reverse pull-down assays indicate that the binding of CLIC4 to dynamin I and 14-3-3zeta is direct. In HEK-293 cells, biochemical and immunofluorescence analyses show partial co-localization of recombinant CLIC4 with caveolin and with functional caveolae, which is consistent with a dynamin-associated role for CLIC4 in caveolar endocytosis. We speculate that brain CLIC4 might be involved in the dynamics of neuronal plasma membrane microdomains (micropatches) containing caveolin-like proteins and might also have other cellular roles related to membrane trafficking. Our results provide the basis for new hypotheses concerning novel ways in which CLIC proteins might be associated with cell membrane remodelling, the control of cell shape, and anion channel activity.


Assuntos
Actinas/metabolismo , Encéfalo/metabolismo , Canais de Cloreto/metabolismo , Dinamina I/metabolismo , Tubulina (Proteína)/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Proteínas 14-3-3 , Sequência de Aminoácidos , Animais , Cavéolas/metabolismo , Caveolina 1 , Caveolinas/metabolismo , Membrana Celular , Células Cultivadas/citologia , Células Cultivadas/metabolismo , Cromatografia de Afinidade , Primers do DNA/química , Endocitose , Glutationa Transferase/metabolismo , Humanos , Canais Iônicos/fisiologia , Espectrometria de Massas , Dados de Sequência Molecular , Neurônios/metabolismo , Fragmentos de Peptídeos/química , Reação em Cadeia da Polimerase , Testes de Precipitina , Ratos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
18.
Arch Biochem Biophys ; 393(2): 329-38, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11556821

RESUMO

Cytochrome P4504A4 (CYP4A4) is a hormonally induced pulmonary cytochrome P450 which metabolizes prostaglandins and arachidonic acid (AA) to their omega-hydroxylated products. Although the physiological function of this enzyme is unknown, prostaglandins play an important role in the regulation of reproductive, vascular, intestinal, and inflammatory systems and 20-hydroxyeicosatetraenoic acid, the omega-hydroxylated product of arachidonate, is a potent vasoconstrictor. Therefore, it is important to obtain sufficient quantities of the protein for kinetic and biophysical characterization. A CYP4A4 construct was prepared and expressed in Escherichia coli. The enzyme was purified, and its activity with substrates prostaglandin E(1) (PGE(1)) and AA was examined in the presence and absence of cytochrome b(5) (cyt b(5)) and with a heme-depleted form of cyt b(5) (apo b(5)). The stimulatory role played by cyt b(5) in this system is not dependent on electron transfer from cyt b(5) to the CYP4A4 as similar stimulation was observed with apo b(5). Rapid kinetic measurement of CYP4A4 electron transfer rates confirmed this result. Both flavin and heme reduction rates were constant in the absence and presence of cyt b(5) or apo b(5). CD spectroscopy demonstrated that a conformational change occurred in CYP4A4 protein upon binding of cyt b(5) or apo b(5). Finally, acetylenic fatty acid inhibitors 17-octadecynoic acid, 12-hydroxy-16-heptadecynoic acid, 15-hexadecynoic acid, and 10-undecynoic acid (10-UDYA) were used to probe the substrate-binding pocket of CYP4A4. The short-chain fatty acid inhibitor 10-UDYA was unable to inhibit either PGE(1) or AA metabolism. All but 10-UDYA were effective inhibitors of CYP4A4.


Assuntos
Alprostadil/metabolismo , Ácido Araquidônico/metabolismo , Hidrocarboneto de Aril Hidroxilases , Sistema Enzimático do Citocromo P-450/metabolismo , Oxigenases de Função Mista/metabolismo , Sítios de Ligação , Dicroísmo Circular , Inibidores das Enzimas do Citocromo P-450 , Sistema Enzimático do Citocromo P-450/química , Família 4 do Citocromo P450 , Inibidores Enzimáticos/farmacologia , Escherichia coli , Ácidos Graxos Monoinsaturados/farmacologia , Cinética , Oxigenases de Função Mista/antagonistas & inibidores , Oxigenases de Função Mista/química , Conformação Proteica , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/metabolismo
19.
Neuroreport ; 12(3): 495-500, 2001 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-11234752

RESUMO

Sensory neurones co-express voltage-gated sodium channels that mediate TTX-sensitive (TTX-S) and TTX-resistant (TTX-R) currents, which may contribute to chronic pain after nerve injury. We previously demonstrated that TTX-R channels were decreased acutely in human sensory cell bodies after central axotomy, but accumulated in nerve terminals after peripheral axotomy. We have now studied the TTX-S channels PN1 and Brain III, using specific antibodies for immunohistochemistry, in dorsal root ganglia (DRG) from 10 patients with traumatic central axotomy, nerves from 16 patients with peripheral axotomy, and controls. PN1 showed temporal changes similar to the TTX-R channels in sensory cell bodies of injured DRG. In contrast, Brain III was found only in injured nerves (not control nerves, or control/central axotomy DRG). PNI and Brain III are distinct targets for novel analgesics.


Assuntos
Gânglios Espinais/lesões , Gânglios Espinais/metabolismo , Plasticidade Neuronal/fisiologia , Neuropeptídeos/metabolismo , Canais de Sódio/metabolismo , Tetrodotoxina/farmacologia , Adulto , Idoso , Especificidade de Anticorpos , Plexo Braquial/citologia , Plexo Braquial/lesões , Plexo Braquial/metabolismo , Linhagem Celular , Feminino , Gânglios Espinais/citologia , Humanos , Rim/citologia , Masculino , Pessoa de Meia-Idade , Canal de Sódio Disparado por Voltagem NAV1.7 , Neurônios Aferentes/química , Neurônios Aferentes/metabolismo , Neuropeptídeos/análise , Neuropeptídeos/imunologia , Canais de Sódio/análise , Canais de Sódio/imunologia , Transfecção
20.
J Biol Chem ; 276(22): 18757-64, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11278595

RESUMO

Mammalian casein kinases I (CKI) belong to a family of serine/threonine protein kinases involved in diverse cellular processes including cell cycle progression, membrane trafficking, circadian rhythms, and Wnt signaling. Here we show that CKIalpha co-purifies with centaurin-alpha(1) in brain and that they interact in vitro and form a complex in cells. In addition, we show that the association is direct and occurs through the kinase domain of CKI within a loop comprising residues 217-233. These residues are well conserved in all members of the CKI family, and we show that centaurin-alpha(1) associates in vitro with all mammalian CKI isoforms. To date, CKIalpha represents the first protein partner identified for centaurin-alpha(1). However, our data suggest that centaurin-alpha(1) is not a substrate for CKIalpha and has no effect on CKIalpha activity. Centaurin-alpha(1) has been identified as a phosphatidylinositol 3,4,5-trisphosphate-binding protein. Centaurin-alpha(1) contains a cysteine-rich domain that is shared by members of a newly identified family of ADP-ribosylation factor guanosine trisphosphatase-activating proteins. These proteins are involved in membrane trafficking and actin cytoskeleton rearrangement, thus supporting a role for CKIalpha in these biological events.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Proteínas Quinases/metabolismo , Proteínas de Peixe-Zebra , Actinas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Animais , Encéfalo/metabolismo , Caseína Quinases , Ciclo Celular , Membrana Celular/metabolismo , Cisteína/química , Citoesqueleto/metabolismo , DNA Complementar/metabolismo , Proteínas Ativadoras de GTPase , Glutationa Transferase/metabolismo , Espectrometria de Massas , Modelos Genéticos , Dados de Sequência Molecular , Peptídeos/metabolismo , Fosforilação , Testes de Precipitina , Ligação Proteica , Biossíntese de Proteínas , Isoformas de Proteínas , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas/metabolismo , Ratos , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Transcrição Gênica , Proteínas Wnt
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