RESUMO
OBJECTIVES: To estimate the intra -and inter-rater consistency of radiologist and neurologist working in pairs attributing DWI-ASPECTS (Diffusion Alberta Stroke Program Early CT Score) in patients with acute middle cerebral artery ischemic stroke referred for mechanical thrombectomy, intravenous thrombolysis or bridging therapy. METHODS: Five neurologists and 5 radiologists working in pairs and in hour period scored independently and in two reading sessions anonymized DWI-ASPECTS of 80 patients presenting with acute anterior ischaemic stroke in our center. We measured agreement between pairs using intraclass correlation coefficients (ICCs). A Fleiss kappa was used for dichotomized (0-6;7-10) and trichotomized (0-3;4-6;7-10) ASPECTS. The interrater distribution of the score in the trichotomized (0-3;4-6;7-10) ASPECTS was calculated. We determined the interrater (Cohen kappa) and intrarater (Fleiss kappa) agreement on the ASPECTS regions. RESULTS: The average DWI-ASPECTS was 6.35 (SD±2.44) for the first reading, and 6.47 (SD±2.44) for the second one. The ICC was 0.853 (95%CI, 0.798-0.896) for the interrater, and 0.862 (95%CI, 0.834-0.885) for the intrarater evaluation. Kappa coefficients were high for dichotomized (k=0.75) and trichotomized (k=0.64) ASPECTS. Evaluators agreement on the ASPECTS category (0-3), (4-6) and (7-10) was 88, 76 and 93% respectively. The anatomic region infarcted was well identified (k=0.70-0.77), except for the internal capsula (k=0.57). Interrater agreement was fair for M5 (k=0.37), moderate for internal capsula (0.52) and substantial for the other regions (0.60-0.79). CONCLUSIONS: Reliability of DWI-ASPECTS is good when determined by radiologist and neurologist working in pairs, which corresponds to our current clinical practice. However, discrepancies are possible for cut-off determination, which may impact the indication of thrombectomy, and for the determination of the exact infarcted region. Agreement to propose category (4-6) is lower than for (0-3) and (8-10) ASPECTS categories.
Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/terapia , Humanos , Neurologistas , Radiologistas , Reprodutibilidade dos Testes , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapiaRESUMO
Currently, we are experiencing a true pandemic of a communicable disease by the virus SARS-CoV-2 holding the whole world firmly in its grasp. Amazingly and unfortunately, this virus uses a metabolic and endocrine pathway via ACE2 to enter our cells causing damage and disease. Our international research training programme funded by the German Research Foundation has a clear mission to train the best students wherever they may come from to learn to tackle the enormous challenges of diabetes and its complications for our society. A modern training programme in diabetes and metabolism does not only involve a thorough understanding of classical physiology, biology and clinical diabetology but has to bring together an interdisciplinary team. With the arrival of the coronavirus pandemic, this prestigious and unique metabolic training programme is facing new challenges but also new opportunities. The consortium of the training programme has recognized early on the need for a guidance and for practical recommendations to cope with the COVID-19 pandemic for the community of patients with metabolic disease, obesity and diabetes. This involves the optimal management from surgical obesity programmes to medications and insulin replacement. We also established a global registry analyzing the dimension and role of metabolic disease including new onset diabetes potentially triggered by the virus. We have involved experts of infectious disease and virology to our faculty with this metabolic training programme to offer the full breadth and scope of expertise needed to meet these scientific challenges. We have all learned that this pandemic does not respect or heed any national borders and that we have to work together as a global community. We believe that this transCampus metabolic training programme provides a prime example how an international team of established experts in the field of metabolism can work together with students from all over the world to address a new pandemic.
Assuntos
COVID-19 , Diabetes Mellitus , Educação Médica Continuada , Obesidade , Pandemias , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/terapia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Humanos , Obesidade/epidemiologia , Obesidade/terapiaRESUMO
BACKGROUND: In ambulant psychiatric care, intellectual disability (id) is often not recognised. Therefore, a Screener for Intelligence and Learning disabilities (scil) was recently introduced to assist recognition. However, because, current therapy is not adjusted for id-related problems, its effectiveness remains unknown.
AIM: To gain insight into adequate adaptation of interventions by professionals for patients with severe mental illness (smi) and id, to improve the quality of care without the need to develop a completely new program of therapy.
METHOD: A qualitative design (n=15) including 8 interviews and one focus group, among psychiatric practitioners and id experts.
RESULTS: Five main themes were identified to adjust therapy: treatment, communication, inclusion of the network, estimation of support needs and self-management. CONCLUSIONS To align therapy with the requirements of patients with smi and id, a patient-oriented approach to care is necessary. Simple but effective modifications, summarised in a toolkit, appear to contribute to this. To offer appropriate care to patients with smi and id, attention is needed for both a support-oriented and a recovery-oriented approach.
Assuntos
Atitude do Pessoal de Saúde , Deficiência Intelectual/terapia , Transtornos Mentais/terapia , Assistência Centrada no Paciente , Comunicação , Grupos Focais , Humanos , Deficiência Intelectual/epidemiologia , Deficiência Intelectual/psicologia , Programas de Rastreamento , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia , Assistência Centrada no Paciente/organização & administração , Pesquisa Qualitativa , Índice de Gravidade de DoençaRESUMO
The revised classification of the periprosthetic membrane (synovial-like interface membrane SLIM) encompasses all pathological alterations which can occur as a result of endoprosthetic replacement of major joints and lead to a reduction in durability of prostheses. This also includes the established consensus classification of SLIM by which aseptic and septic prosthetic loosening can be subdivided into four histological types and histopathological criteria for additional pathologies: endoprosthesis-associated arthrofibrosis, immunological/allergic alterations and osseous pathologies. This revision represents the foundation for the histopathological diagnostics of the total spectrum of diseases associated with joint prostheses, is a suitable basis for a standardized diagnostic procedure and etiological clarification of endoprosthesis failure and also as a data standard for endprosthesis registers, in particular for registers based on routine data (e.g. German endoprosthesis register).
Assuntos
Artropatias/classificação , Artropatias/diagnóstico , Prótese Articular/efeitos adversos , Guias de Prática Clínica como Assunto , Terminologia como Assunto , Alemanha , Humanos , Artropatias/etiologiaRESUMO
To understand how the nucleosome remodeling and deacetylase (NuRD) complex regulates enhancers and enhancer-promoter interactions, we have developed an approach to segment and extract key biophysical parameters from live-cell three-dimensional single-molecule trajectories. Unexpectedly, this has revealed that NuRD binds to chromatin for minutes, decompacts chromatin structure and increases enhancer dynamics. We also uncovered a rare fast-diffusing state of enhancers and found that NuRD restricts the time spent in this state. Hi-C and Cut&Run experiments revealed that NuRD modulates enhancer-promoter interactions in active chromatin, allowing them to contact each other over longer distances. Furthermore, NuRD leads to a marked redistribution of CTCF and, in particular, cohesin. We propose that NuRD promotes a decondensed chromatin environment, where enhancers and promoters can contact each other over longer distances, and where the resetting of enhancer-promoter interactions brought about by the fast decondensed chromatin motions is reduced, leading to more stable, long-lived enhancer-promoter relationships.
Assuntos
Cromatina , Nucleossomos , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Regiões Promotoras Genéticas , Elementos Facilitadores GenéticosRESUMO
INTRODUCTION: Recent evidence suggests that patients with malignant pleural mesothelioma (MPM) undergoing extended pleurectomy/decortication (eP/D) with metastasis to the posterior intercostal lymph nodes (PILN) have a worse prognosis. In this study, we determine if MPM PILN metastasis can be reliably detected on computed tomography (CT). MATERIALS AND METHODS: Preoperative staging CT exams were reviewed for the presence of PILN in MPM patients undergoing eP/D between 2007-2013 with surgical sampling of their PILN. CT images were reviewed by two thoracic radiologists blinded to clinical records, including operative pathology reports. The number and short axis size of PILN were recorded and correlated with surgical pathology. Statistical analysis examined the value of preoperative CT to detect metastatic PILN. RESULTS: Of 36 patients that underwent eP/D with PILN sampling had preoperative CT images for review. At surgery, 22 of these patients had metastatic PILN and 14 had benign PILN. The positive and negative predictive values for one or more nodes seen on preoperative CT were 60 % and 38 % respectively. The number of PILN on preoperative CT did not predict metastasis (pâ¯=â¯0.40) with an average of 2 PILN seen, regardless of PILN pathology. The average nodal short axis size was 4.6â¯mm and 4.8â¯mm for benign and malignant PILN, respectively, and PILN short axis size did not predict metastasis (pâ¯=â¯0.39). There was little inter-observer variability between the size and number of nodes detected by each radiologist. CONCLUSIONS: CT does not reliably identify metastatic PILN on preoperative CT for patients with MPM undergoing extended pleurectomy/decortication.
Assuntos
Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurais , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Linfonodos/cirurgia , Mesotelioma/diagnóstico por imagem , Mesotelioma/cirurgia , Estadiamento de Neoplasias , Neoplasias Pleurais/diagnóstico por imagem , Neoplasias Pleurais/patologia , Tomografia Computadorizada por Raios XRESUMO
Measles causes a profound immune suppression which is responsible for the high morbidity and mortality induced by secondary infections. Dendritic cells (DC) are professional antigen-presenting cells required for initiation of primary immune responses. To determine whether infection of DC by measles virus (MV) may play a role in virus-induced suppression of cell-mediated immunity, we examined the ability of CD1a+ DC derived from cord blood CD34+ progenitors and Langerhans cells isolated from human epidermis to support MV replication. Here we show that both cultured CD1a+ DC and epidermal Langerhans cells can be infected in vitro by both vaccine and wild type strains of MV. DC infection with MV resulted within 24-48 h in cell-cell fusion, cell surface expression of hemagglutinin, and virus budding associated with production of infectious virus. MV infection of DC completely abrogated the ability of the cells to stimulate the proliferation of naive allogeneic CD4+ T cell as early as day 2 of mixed leukocyte reaction (MLR) (i.e., on day 4 of DC infection). Mannose receptor-mediated endocytosis and viability studies indicated that the loss of DC stimulatory function could not be attributed to the death or apoptosis of DC. This total loss of DC stimulatory function required viral replication in the DC since ultraviolet (UV)-inactivated MV or UV-treated supernatant from MV-infected DC did not alter the allostimulatory capacity of DC. As few as 10 MV- infected DC could block the stimulatory function of 10(4) uninfected DC. More importantly, MV-infected DC, in which production of infectious virus was blocked by UV treatment or paraformaldehyde fixation, actively suppressed allogeneic MLR upon transfer to uninfected DC-T-cultures. Thus, the mechanisms which contribute to the loss of the allostimulatory function of DC include both virus release and active suppression mediated by MV-infected DC, independent of virus production. These data suggest that carriage of MV by DC may facilitate virus spreading to secondary lymphoid organs and that MV replication in DC may play a central role in the general immune suppression observed during measles.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/imunologia , Células Dendríticas/virologia , Vírus do Sarampo/imunologia , Vírus do Sarampo/patogenicidade , Comunicação Celular/imunologia , Sobrevivência Celular , Células Cultivadas , Efeito Citopatogênico Viral , Células Dendríticas/patologia , Hemaglutininas Virais/metabolismo , Humanos , Tolerância Imunológica , Isoantígenos , Células de Langerhans/imunologia , Células de Langerhans/virologia , Ativação Linfocitária , Teste de Cultura Mista de Linfócitos , Sarampo/imunologia , Sarampo/patologia , Sarampo/virologia , Vírus do Sarampo/fisiologia , Microscopia Eletrônica , Replicação ViralRESUMO
BACKGROUND: Hashimoto encephalopathy (HE) is a rare autoimmune disorder. It is defined as a 'corticosteroid-responsive encephalopathy associated with thyroiditis'. CLINICAL OBSERVATION: We describe a boy who suffered from HE, responded only to intravenous immunoglobulin therapy. This is the first case report of immunoglobulin therapy in paediatric HE. CONCLUSION: After review of the literature, we recommend that unexplained encephalopathy in children should lead to evaluation of thyroid autoantibody titres. Immunoglobulins should be considered.
Assuntos
Encefalite/terapia , Doença de Hashimoto/terapia , Imunização Passiva , Criança , Encefalite/complicações , Epilepsia/etiologia , Doença de Hashimoto/complicações , Humanos , Imunoglobulinas Intravenosas , Masculino , Resultado do TratamentoRESUMO
The translational regulator protein regA is encoded by the T4 bacteriophage and binds to a region of messenger RNA (mRNA) that includes the initiator codon. RegA is unusual in that it represses the translation of about 35 early T4 mRNAs but does not affect nearly 200 other mRNAs. The crystal structure of regA was determined at 1.9 A resolution; the protein was shown to have an alpha-helical core and two regions with antiparallel beta sheets. One of these beta sheets has four antiparallel strands and has some sequence homology to RNP-1 and RNP-2, which are believed to be RNA-binding motifs and are found in a number of known RNA-binding proteins. Structurally guided mutants may help to uncover the basis for this variety of RNA interaction.
Assuntos
Bacteriófago T4/química , Proteínas de Ligação a RNA/química , Proteínas Virais/química , Sequência de Aminoácidos , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Relação Estrutura-AtividadeRESUMO
At times clinicians and pathologists underestimate the value and significance of histopathological diagnostics for synovial tissue. However, the most common diseases of the synovium show specific morphological hallmarks that allow an exact diagnosis. Using the synovitis score allows one to distinguish between degenerative (low-grade synovitis) and inflammatory rheumatic (high-grade synovitis) diseases. Synovial biopsies are not only especially indicated when there are atypical patterns of arthritis, clinical options have been exhausted or monarthritis of unknown origin occurs, but also in patients with known rheumatoid arthritis. Joint infections, crystal-induced arthritis or pigmented villonodular synovitis can also be diagnosed as secondary synovial diseases. Providing clinical information when submitting biopsies/tissue specimens is essential to classify even unspecific morphological changes. Immunohistochemical staining, polarization microscopy or molecular biology techniques (PCR) may be used to ensure diagnoses.
Assuntos
Biópsia/métodos , Doenças Reumáticas/patologia , Membrana Sinovial/patologia , Sinovite/patologia , HumanosRESUMO
BACKGROUND: Prostate-specific membrane antigen (PSMA) positron emission tomography (PET) can be used to locate lesions based on PSMA avidity, however guidelines on its use are limited by its infancy. We aimed to compare multiparametric magnetic resonance imaging (mpMRI) and PSMA PET/CT to prostatectomy histopathology. METHODS: We conducted a chart review from February 2015 to January 2017 of 50 male patients staged for prostate cancer using PSMA PET/CT and mpMRI who then underwent radical prostatectomy. Pre-operative PSMA PET/CT and mpMRI were paired with corresponding histopathology. Correlations, sensitivity, and specificity were used for comparisons. RESULTS: A total of 81 lesions were confirmed by histopathology. Fifty index lesions were detected by histopathology, all of which were detected by PSMA PET/CT (100% detection), and 47 by mpMRI (94% detection). Thirty-one histologically confirmed secondary lesions were detected, 29 of which were detected by PSMA PET/CT (93.5% detection), and 16 by mpMRI (51.6% detection). PSMA had better sensitivity for index lesion localization than mpMRI (81.1 vs. 64.8%). Specificity was similar for PSMA PET/CT and mpMRI (84.6 vs. 82.7%). SUVmax of index lesions ranged from 2.9 to 39.6 (M = 9.27 ± 6.41). Index lesion SUVmax was positively correlated with PSA (rho = 0.48, p < 0.001) and ISUP grade (rho = 0.51, p < 0.001). CONCLUSIONS: PSMA-PET/CT provided superior detection of prostate cancer lesions with better sensitivity than mpMRI. PSMA-PET/CT can be used to enhance locoregional mpMRI to provide improved detection and characterization of lesions.
Assuntos
Ácido Edético/análogos & derivados , Imageamento por Ressonância Magnética/métodos , Oligopeptídeos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias da Próstata/patologia , Compostos Radiofarmacêuticos , Idoso , Seguimentos , Isótopos de Gálio , Radioisótopos de Gálio , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Prostatectomia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgiaRESUMO
An 83-base-pair-long hepatitis B virus DNA fragment efficiently activates the transcription of the heterologous globin gene promoter. This fragment contains binding sites for at least four distinct cellular factors termed E, TGT3, EP, and NF-I. E is a positively acting factor, responsive to phorbol ester. EP is apparently identical to the factor EF-C that binds to the polyomavirus enhancer. The conservation of the binding site sequences for most of these factors in the genomes of other members of the hepadnavirus family suggests that these viruses share common enhancer elements.
Assuntos
Elementos Facilitadores Genéticos , Vírus da Hepatite B/genética , Sequência de Bases , Sítios de Ligação , Mapeamento Cromossômico , DNA Viral/genética , DNA Viral/metabolismo , Proteínas de Ligação a DNA/metabolismo , Genes Virais , Dados de Sequência Molecular , Fatores de Transcrição/metabolismoRESUMO
Transgenic chloroplasts offer unique advantages in plant biotechnology, including high-level foreign protein expression, absence of epigenetic effects, and gene containment due to the lack of transgene transmission through pollen. However, broad application of plastid genome engineering in biotechnology has been largely hampered by both the lack of chloroplast transformation systems for major crop plants and the usually low plastid gene expression levels in nongreen tissues such as fruits, tubers, and other storage organs. Here we describe the development of a plastid transformation system for tomato, Lycopersicon esculentum. This is the first report on the generation of fertile transplastomic plants in a food crop with an edible fruit. We show that chromoplasts in the tomato fruit express the transgene to approximately 50% of the expression levels in leaf chloroplasts. Given the generally very high foreign protein accumulation rates that can be achieved in transgenic chloroplasts (>40% of the total soluble protein), this system paves the way to efficient production of edible vaccines, pharmaceuticals, and antibodies in tomato.
Assuntos
Biotecnologia/métodos , Plantas Geneticamente Modificadas , Plastídeos/genética , Solanum lycopersicum/genética , Transformação Genética , Transgenes , Cloroplastos/metabolismo , Immunoblotting , Modelos Genéticos , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Fatores de TempoRESUMO
The transcription factor hypoxia-inducible factor (HIF)-1 is an important mediator of hypoxic adaptation of tumor cells and controls several genes that have been implicated in tumor growth. Oxygen-dependent degradation of HIF-1alpha, the regulatory subunit, requires binding to the von Hippel Lindau (VHL) protein. Because functional inactivation of the VHL tumor suppressor gene occurs in up to 70% of clear cell renal carcinomas, we investigated whether this results in overexpression of HIF-1alpha and its target genes. Immunoblotting revealed increased expression of HIF-1alpha in 24 of 32 (75%) clear cell renal carcinomas but only 3 of 8 non-clear cell renal tumors. Somatic mutations of the VHL gene were detected only in clear cell renal carcinomas that overexpressed HIF-1alpha. None of the HIF-1alpha-negative tumors displayed a VHL mutation. The level of HIF-1alpha mRNA was not different between tumors and adjacent kidney tissue. Immunohistochemistry revealed distinct patterns of nuclear staining for HIF-1alpha, depending on histological type and overall abundance of HIF-1alpha. In those clear cell renal carcinomas that showed increased expression on immunoblots, HIF-1alpha was expressed in almost all cells. In the remaining clear cell and in non-clear cell tumors, staining was focal; these different patterns thus were compatible with genetic stabilization in contrast to microenvironmental stimulation of HIF-1alpha as the primary mechanism. The mRNA expression of two known target genes of HIF-1alpha, vascular endothelial growth factor and glucose transporter 1, increased progressively with increasing amounts of HIF-1alpha in tumor extracts. In addition, glucose transporter 1 protein levels correlated with HIF-1alpha abundance. In conclusion, the data provide in vivo evidence for a constitutive up-regulation of HIF-1alpha in the majority of clear cell renal carcinomas, which leads to more widespread accumulation of this transcription factor than hypoxic stimulation. These observations are most likely linked to functional inactivation of the VHL gene product. Increased expression of HIF-1alpha is associated with alterations in gene expression patterns that are likely to contribute to tumor phenotype and progression.
Assuntos
Carcinoma de Células Renais/genética , Proteínas de Ligação a DNA/genética , Fatores de Crescimento Endotelial/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/genética , Ligases , Linfocinas/genética , Proteínas de Transporte de Monossacarídeos/genética , Proteínas Nucleares/genética , Fatores de Transcrição , Proteínas Supressoras de Tumor , Ubiquitina-Proteína Ligases , Adenocarcinoma de Células Claras/genética , Adenocarcinoma de Células Claras/metabolismo , Carcinoma de Células Renais/metabolismo , Hipóxia Celular/genética , Análise Mutacional de DNA , Proteínas de Ligação a DNA/biossíntese , Fatores de Crescimento Endotelial/biossíntese , Transportador de Glucose Tipo 1 , Humanos , Fator 1 Induzível por Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia , Imuno-Histoquímica , Neoplasias Renais/metabolismo , Linfocinas/biossíntese , Proteínas de Transporte de Monossacarídeos/biossíntese , Proteínas Nucleares/biossíntese , Proteínas/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , Proteína Supressora de Tumor Von Hippel-LindauAssuntos
Pâncreas , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Pâncreas/diagnóstico por imagem , Pâncreas/cirurgiaRESUMO
The nucleosome remodeling deacetylase (NuRD) complex is a highly conserved regulator of chromatin structure and transcription. Structural studies have shed light on this and other chromatin modifying machines, but much less is known about how they assemble and whether stable and functional sub-modules exist that retain enzymatic activity. Purification of the endogenous Drosophila NuRD complex shows that it consists of a stable core of subunits, while others, in particular the chromatin remodeler CHD4, associate transiently. To dissect the assembly and activity of NuRD, we systematically produced all possible combinations of different components using the MultiBac system, and determined their activity and biophysical properties. We carried out single-molecule imaging of CHD4 in live mouse embryonic stem cells, in the presence and absence of one of core components (MBD3), to show how the core deacetylase and chromatin-remodeling sub-modules associate in vivo. Our experiments suggest a pathway for the assembly of NuRD via preformed and active sub-modules. These retain enzymatic activity and are present in both the nucleus and the cytosol, an outcome with important implications for understanding NuRD function.
Assuntos
Histona Desacetilases/metabolismo , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Nucleossomos/metabolismo , Animais , Núcleo Celular/metabolismo , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina/fisiologia , Citosol/metabolismo , Drosophila/metabolismo , Camundongos , Subunidades Proteicas/metabolismo , Células-Tronco/metabolismoRESUMO
A jun related cDNA and its corresponding genomic fragment were cloned from human cells and sequenced. Polymerase chain reaction analysis showed that this gene is the human homologue of the mouse jun-D gene despite the fact that the degree of amino acid sequence conservation between the two is much poorer (77.3%) than that found between the homologues of c-jun and jun-B (95-98%). The product of this gene binds an AP-1 site and upon cotransfection stimulates the activity of a promoter that bears an AP-1 site. The level of activation is comparable to that of v-jun and the activity of both is further stimulated by v-fos. Deletion mutants of the gene that lack the best conserved region in the activating domain are poorly active. However, our data suggest that the activating domain is not confined exclusively to the conserved regions. Interestingly, at high concentrations human jun-D displays decreased activity which cannot be explained by a simple self squelching model.
Assuntos
Proteínas de Ligação a DNA/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Southern Blotting , Deleção Cromossômica , Mapeamento Cromossômico , Clonagem Molecular , Proteínas de Ligação a DNA/fisiologia , Humanos , Camundongos , Dados de Sequência Molecular , Plasmídeos , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas/genética , Regiões Promotoras Genéticas/fisiologia , Proteínas Proto-Oncogênicas c-jun , Homologia de Sequência do Ácido Nucleico , Fatores de Transcrição/fisiologia , Transcrição Gênica , Ativação Transcricional/fisiologiaRESUMO
OBJECTIVE: Pigmented villonodular synovitis (PVNS) is a proliferative lesion originating from synovial tissue with a locally aggressive behaviour. We analysed the pathogenetic role of apoptosis resistance for sustained cell proliferation in PVNS. METHODS: The expression of bcl-2, p53 and Ki-67 was examined in 80 cases of PVNS using immunohistochemistry. In 43 of these cases, DNA content and distribution of cell-cycle phases were investigated by flow cytometry. Additionally, 10 cases of PVNS were analysed by multi-parametric flow cytometry for expression of p53, caspase3, and bcl-2 and by TUNEL to detect DNA fragmentation. RESULTS: No apoptotic cell fractions were detected in any investigated cases. Expression of bcl-2 was found in 84% of cases (up to 6.5% of cells) and was significantly associated with DNA-fragmentation observed by TUNEL (p=0.037). Orthologous p53 expression was observed in 37% of cases. The level of p53 expression correlated with the proliferative activity and the expression of both caspase3 (p=0.017) and bcl-2 (p=0.0013). (No statistically significant correlations between expression of bcl-2, p53, caspase3, DNA fragmentation or proliferative index and age, sex of patients, disease recurrence, growth pattern or size of lesion were found). CONCLUSION: Apoptosis resistance is a critical event in the progression of PVNS and may contribute to the survival of the proliferating synovial cells in PVNS and to the permanent slow progression of these lesions.