Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 325
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
BMC Psychiatry ; 24(1): 481, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956493

RESUMO

BACKGROUND: Patients' online record access (ORA) enables patients to read and use their health data through online digital solutions. One such solution, patient-accessible electronic health records (PAEHRs) have been implemented in Estonia, Finland, Norway, and Sweden. While accumulated research has pointed to many potential benefits of ORA, its application in mental healthcare (MHC) continues to be contested. The present study aimed to describe MHC users' overall experiences with national PAEHR services. METHODS: The study analysed the MHC-part of the NORDeHEALTH 2022 Patient Survey, a large-scale multi-country survey. The survey consisted of 45 questions, including demographic variables and questions related to users' experiences with ORA. We focused on the questions concerning positive experiences (benefits), negative experiences (errors, omissions, offence), and breaches of security and privacy. Participants were included in this analysis if they reported receiving mental healthcare within the past two years. Descriptive statistics were used to summarise data, and percentages were calculated on available data. RESULTS: 6,157 respondents were included. In line with previous research, almost half (45%) reported very positive experiences with ORA. A majority in each country also reported improved trust (at least 69%) and communication (at least 71%) with healthcare providers. One-third (29.5%) reported very negative experiences with ORA. In total, half of the respondents (47.9%) found errors and a third (35.5%) found omissions in their medical documentation. One-third (34.8%) of all respondents also reported being offended by the content. When errors or omissions were identified, about half (46.5%) reported that they took no action. There seems to be differences in how patients experience errors, omissions, and missing information between the countries. A small proportion reported instances where family or others demanded access to their records (3.1%), and about one in ten (10.7%) noted that unauthorised individuals had seen their health information. CONCLUSIONS: Overall, MHC patients reported more positive experiences than negative, but a large portion of respondents reported problems with the content of the PAEHR. Further research on best practice in implementation of ORA in MHC is therefore needed, to ensure that all patients may reap the benefits while limiting potential negative consequences.


Assuntos
Registros Eletrônicos de Saúde , Serviços de Saúde Mental , Humanos , Registros Eletrônicos de Saúde/estatística & dados numéricos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Estônia , Noruega , Finlândia , Serviços de Saúde Mental/estatística & dados numéricos , Suécia , Inquéritos e Questionários , Adulto Jovem , Idoso , Acesso dos Pacientes aos Registros , Adolescente
2.
Prostate ; 82(5): 505-516, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35037287

RESUMO

INTRODUCTION: Castration-resistant prostate cancer (CRPC) remains dependent on androgen receptor (AR) signalling, which is largely driven by conversion of adrenal androgen precursors lasting after castration. Abiraterone, an inhibitor of the steroidogenic enzyme CYP17A1, has been demonstrated to reduce adrenal androgen synthesis and prolong CRPC patient survival. To study mechanisms of resistance to castration and abiraterone, we created coculture models using human prostate and adrenal tumours. MATERIALS AND METHODS: Castration-naïve and CRPC clones of VCaP were incubated with steroid substrates or cocultured with human adrenal cells (H295R) and treated with abiraterone or the antiandrogen enzalutamide. Male mice bearing VCaP xenografts with and without concurrent H295R xenografts were castrated and treated with placebo or abiraterone. Response was assessed by tumour growth and PSA release. Plasma and tumour steroid levels were assessed by LC/MS-MS. Quantitative polymerase chain reaction determined steroidogenic enzyme, nuclear receptor and AR target gene expression. RESULTS: In vitro, adrenal androgens induced castration-naïve and CRPC cell growth, while precursors steroids for de novo synthesis did not. In a coculture system, abiraterone blocked H295R-induced growth of VCaP cells. In vivo, H295R promoted castration-resistant VCaP growth. Abiraterone only inhibited VCaP growth or PSA production in the presence of H295R. Plasma steroid levels demonstrated CYP17A1 inhibition by abiraterone, whilst CRPC tumour tissue steroid levels showed no evidence of de novo intratumoural androgen production. Castration-resistant and abiraterone-resistant VCaP tumours had increased levels of AR, AR variants and glucocorticoid receptor (GR) resulting in equal AR target gene expression levels compared to noncastrate tumours. CONCLUSIONS: In our model, ligand-dependent AR-regulated regrowth of CRPC was predominantly supported via adrenal androgen precursor production while there was no evidence for intratumoural androgen synthesis. Abiraterone-resistant tumours relied on AR overexpression, expression of ligand-independent AR variants and GR signalling.


Assuntos
Androgênios , Neoplasias de Próstata Resistentes à Castração , Androgênios/metabolismo , Androstenos/farmacologia , Androstenos/uso terapêutico , Animais , Linhagem Celular Tumoral , Humanos , Ligantes , Masculino , Camundongos , Nitrilas/uso terapêutico , Orquiectomia , Antígeno Prostático Específico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Receptores de Glucocorticoides
3.
Neuroimage ; 194: 283-290, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30898654

RESUMO

Recent findings have been challenging current understanding of how fast the human brain change its structural and functional connections in response to training. One powerful way to deepen the inner workings of human brain plasticity is using neurofeedback (NFB) by fMRI, a technique that allows self-induced brain plasticity by means of modulating brain activity in real time. In the present randomized, double-blind and sham-controlled study, we use NFB to train healthy individuals to reinforce brain patterns related to motor execution while performing a motor imagery task, with no overt movement. After 1 h of NFB training, participants displayed increased fractional anisotropy (FA) in the sensorimotor segment of corpus callosum and increased functional connectivity of the sensorimotor resting state network. Increased functional connectivity was also observed in the default mode network. These results were not observed in the control group, which was trained with sham feedback. To our knowledge, this is the first demonstration of white matter FA changes following a very short training schedule (<1 h). Our results suggest that NFB by fMRI can be an interesting tool to explore dynamic aspects of brain plasticity and open new venues for investigating brain plasticity in healthy individuals and in neurological conditions.


Assuntos
Encéfalo/fisiologia , Imaginação/fisiologia , Vias Neurais/fisiologia , Neurorretroalimentação/métodos , Plasticidade Neuronal/fisiologia , Adulto , Método Duplo-Cego , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Atividade Motora
4.
Psychol Med ; 47(4): 597-607, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27821193

RESUMO

BACKGROUND: A high proportion of patients with remitted major depressive disorder (MDD) will experience recurring episodes, whilst some develop resilience and remain in recovery. The neural basis of resilience to recurrence is elusive. Abnormal resting-state connectivity of the subgenual cingulate cortex (sgACC) was previously found in cross-sectional studies of MDD, suggesting its potential pathophysiological importance. The current study aimed to investigate whether resting-state connectivity to a left sgACC seed region distinguishes resilient patients from those developing recurring episodes. METHOD: A total of 47 medication-free remitted MDD patients and 38 healthy controls underwent resting-state functional magnetic resonance imaging (fMRI) at baseline. Over 14 months, 30 patients remained resilient whilst 17 experienced a recurring episode. RESULTS: Attenuated interhemispheric left-to-right sgACC connectivity distinguished the resilient from the recurring-episode and control groups and was not correlated with residual depressive symptoms. CONCLUSIONS: The current study revealed a neural signature of resilience to recurrence in MDD and thereby elucidates the role of compensatory adaptation in sgACC networks.


Assuntos
Conectoma/métodos , Transtorno Depressivo Maior/fisiopatologia , Suscetibilidade a Doenças , Giro do Cíngulo/fisiopatologia , Adulto , Transtorno Depressivo Maior/diagnóstico por imagem , Feminino , Seguimentos , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva , Indução de Remissão , Adulto Jovem
5.
Neth Heart J ; 25(2): 91-99, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27966187

RESUMO

INTRODUCTION: Three-dimensional rotational angiography (3DRA) has been used in the guidance of various transcatheter therapies including percutaneous pulmonary valve implantation (PPVI). The most recently available 3D image fusion software (VesselNavigator, Philips) extends this technology to use pre-registered computed tomography or magnetic resonance imaging datasets, promising reductions in contrast and radiation exposure along with shorter procedural times. METHODS: In this retrospective review, patients were assigned to three groups according to the mode of imaging guidance: two-dimensional angiography (2DA), 3DRA and VesselNavigator (VN) assisted valve implantation. Patient characteristics and catheterisation data were reviewed with a focus on contrast and radiation exposure, fluoroscopy, and procedural times. RESULTS: Between July 2012 and June 2016, 21 patients underwent PPVI: 8 with 2D guidance, 6 patients with 3DRA and most recently 7 patients with VN assistance. Patents in the VN group received significantly less absolute and weight indexed contrast when compared with those with 2DA or 3DRA guided PPVI. Patients in the 2DA group received a significantly higher total dose area product radiation dose and air kerma in comparison with patients with 3DRA and VN guided intervention. Application of VN resulted in the shortest fluoroscopy time, although not statistically significant, and a significantly shorter study time when compared with 2DA. CONCLUSIONS: Utilisation of pre-intervention image manipulation with VesselNavigator for 3D guidance of PPVI results in a reduction in contrast and radiation exposure and study time as compared with traditional 2D guidance, and contrast usage as compared with 3DRA.

6.
Sci Rep ; 14(1): 7951, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575721

RESUMO

Mangrove forests reduce wave attack along tropical and sub-tropical coastlines, decreasing the wave loads acting on coastal protection structures. Mangrove belts seaward of embankments can therefore lower their required height and decrease their slope protection thickness. Wave reduction by mangroves depends on tree frontal surface area and stability against storms, but both aspects are often oversimplified or neglected in coastal protection designs. Here we present a framework to evaluate how mangrove belts influence embankment designs, including mangrove growth over time and failure by overturning and trunk breakage. This methodology is applied to Sonneratia apetala mangroves seaward of embankments in Bangladesh, considering forest widths between 10 and 1000 m (cross-shore). For water depths of 5 m, wave reduction by mangrove forests narrower than 1 km mostly affects the slope protection and the bank erodibility, whereas the required embankment height is less influenced by mangroves. Sonneratia apetala trees experience a relative maximum in wave attenuation capacity at 10 years age, due to their large submerged canopy area. Once trees are more than 20 years old, their canopy is emergent, and most wave attenuation is caused by trunk and roots. Canopy emergence exposes mangroves to wind loads, which are much larger than wave loads, and can cause tree failure during cyclones. These results stress the importance of including tree surface area and stability models when predicting coastal protection by mangroves.

7.
J Steroid Biochem Mol Biol ; 236: 106446, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38104728

RESUMO

Prostate cancer (PC) is dependent on androgen receptor (AR) activation by testosterone and 5α-dihydrotestosterone (DHT). Intratumoral androgen accumulation and activation despite systemic androgen deprivation therapy underlies the development of castration-resistant PC (CRPC), but the precise pathways involved remain controversial. Here we investigated the differential contributions of de novo androgen biosynthesis and androgen precursor conversion to androgen accumulation. Steroid flux analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was performed on (CR)PC cell lines and fresh patient PC tissue slices after incubation with classic and alternative biosynthesis intermediates, alongside quantitative PCR analysis for steroidogenic enzyme expression. Activity of CYP17A1 was undetectable in all PC cell lines and patient PC tissue slices. Instead, steroid flux analysis confirmed the generation of testosterone and DHT from adrenal precursors and reactivation of androgen metabolites. Precursor steroids upstream of DHEA were converted down the first steps of the alternative DHT biosynthesis pathway, but did not proceed through to active androgen generation. Comprehensive steroid flux analysis of (CR)PC cells provides strong evidence against intratumoral de novo androgen biosynthesis and demonstrates that androgen precursor steroids downstream of CYP17A1 activities constitute the major source of intracrine androgen generation.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Androgênios/metabolismo , Antagonistas de Androgênios , Cromatografia Líquida , Espectrometria de Massas em Tandem , Testosterona/metabolismo , Di-Hidrotestosterona/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Esteroides/metabolismo , Linhagem Celular Tumoral , Esteroide 17-alfa-Hidroxilase/genética , Esteroide 17-alfa-Hidroxilase/metabolismo
8.
NPJ Precis Oncol ; 7(1): 44, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37202469

RESUMO

Zebrafish xenotransplantation models are increasingly applied for phenotypic drug screening to identify small compounds for precision oncology. Larval zebrafish xenografts offer the opportunity to perform drug screens at high-throughput in a complex in vivo environment. However, the full potential of the larval zebrafish xenograft model has not yet been realized and several steps of the drug screening workflow still await automation to increase throughput. Here, we present a robust workflow for drug screening in zebrafish xenografts using high-content imaging. We established embedding methods for high-content imaging of xenografts in 96-well format over consecutive days. In addition, we provide strategies for automated imaging and analysis of zebrafish xenografts including automated tumor cell detection and tumor size analysis over time. We also compared commonly used injection sites and cell labeling dyes and show specific site requirements for tumor cells from different entities. We demonstrate that our setup allows us to investigate proliferation and response to small compounds in several zebrafish xenografts ranging from pediatric sarcomas and neuroblastoma to glioblastoma and leukemia. This fast and cost-efficient assay enables the quantification of anti-tumor efficacy of small compounds in large cohorts of a vertebrate model system in vivo. Our assay may aid in prioritizing compounds or compound combinations for further preclinical and clinical investigations.

9.
Biomed Phys Eng Express ; 8(5)2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35835081

RESUMO

Microwave imaging (MWI) systems are being investigated for breast cancer diagnostics as an alternative to conventional x-ray mammography and breast ultrasound. This work aims at a next generation of tissue-mimicking phantoms modelling the temperature-dependent dielectric properties of breast tissue over a large frequency bandwidth. Such phantoms can be used to develop a novel kind of MWI systems that exploit the temperature-dependent permittivity of tissue as a natural contrast agent. Due to the higher water content in tumor tissue, a temperature increase leads to a different change in the complex permittivity compared to surrounding tissue. This will generate a tumor dominated scattering response when the overall tissue temperature increases by a few degrees, e.g. through the use of microwave hyperthermia systems. In that case a differential diagnostic image can be calculated between microwave measurements at reference (around 37 °C) and elevated temperature conditions. This work proposes the design and characterization of agar-oil-glycerin phantoms for fatty, glandular, skin and tumor tissue. The characterization includes measurements with an open-ended coaxial probe and a network analyzer for the frequency range from 50 MHz to 20 GHz in a temperature-controlled environment covering the temperature range from 25 °C to 46 °C. The phantoms show an unique temperature response over the considered frequency bandwidth leading to significant changes in the real and imaginary part of the complex permittivity. Comparative studies with porcine skin and fat tissue show a qualitative agreement.


Assuntos
Micro-Ondas , Pele , Animais , Imagens de Fantasmas , Compostos Radiofarmacêuticos , Suínos , Temperatura , Água
10.
Postgrad Med ; 134(3): 277-287, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34895019

RESUMO

OBJECTIVES: Treating chronic pain patients with multimodal pain therapy (MMPT) alters perception, awareness, and processing of pain at multiple therapeutic levels. Several clinical observations suggest that the effects of therapy may go beyond the possible sum of each level of therapy and may be due to a central descending inhibitory effect measurable by conditioned pain modulation (CPM). Thus, we investigated whether CPM is able to identify a group of patients that benefit particularly from MMPT. METHODS: This was an observational prospective cohort study. Patients were hospitalized on a special pain medicine ward with specially trained staff for 10 days. The patients were questioned and had investigations before and shortly after MMPT and were followed-up on 3 months post discharge. Before and after treatment, subjects were investigated via CPM and quantitative sensory testing (QST) as well as completing questionnaires. The study was registered in the German Clinical Trials Register (DRKS00006850). RESULTS: During the study period of 24 months, 224 chronic pain patients were recruited. 51 percent of patients completed the study period. There was an improvement in overall groups regarding all domains assessed, lasting beyond the end of the intervention. Patients with a sufficient CPM effect, defined as a reduction in pain during the conditioning stimulus, at baseline did show a more pronounced reduction in mean pain ratings than those without. This was not the case 3 months after therapy. Furthermore, sufficient CPM was identified as a predictor for pain reduction using a linear regression model. CONCLUSION: In conclusion, this study shows that while a heterogeneous group of patients with chronic pain disorders does sustainably benefit from MMPT in general, patients with a sufficient CPM effect do show a more pronounced decrease in pain ratings directly after therapy in comparison to those without.


Pain at one body site can be reduced, when another painful stimulus occurs at the same time. This mechanism is referred to as conditioned pain modulation (CPM).Some patients with chronic pain are treated using different methods such as medication, physiotherapy, and patient education in an in-patient setting, referred to as multimodal pain therapy (MMST). To improve pain therapy, it is vital to identify whether patients who respond especially well to a certain treatment show specific characteristics (i.e. mechanism-based therapy). We investigated whether the prospect of success of MMST is related to how well CPM works in patients. We assessed the CPM effect and sensory function of 224 patients with chronic pain before and after therapy to answer this question. Additionally, patients completed questionnaires about their pain, mood, quality of life, and sleep directly after therapy and three months later. All patients showed improvement after therapy, but in those in which CPM worked well, pain was reduced stronger than in those in which CPM did not. Three months after treatment, the difference disappeared.


Assuntos
Dor Crônica , Assistência ao Convalescente , Dor Crônica/tratamento farmacológico , Humanos , Limiar da Dor , Alta do Paciente , Estudos Prospectivos
11.
J Cell Biol ; 135(4): 1139-50, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8922392

RESUMO

Cell contact with the extracellular matrix component hyaluronic acid (HA) plays an important role in many developmental, physiological, and pathological processes, although the regulation of this contact is poorly understood. CD44 proteins carry an amino acid motif that mediates affinity to HA. Artificial clustering of the smallest 85-kD isoform of CD44 (CD44s) has previously been shown to promote binding of the protein to soluble HA (Lesley, J., R. Hyman, and P.W. Kincade. 1993. Adv. Immunol. 54:271-335; Persche, A., J. Lesley, N. English, I. Trowbridge, and R. Hyman. 1995. Eur. J. Immunol. 25:495-501). Here we show that in rat pancreatic carcinoma cells, splice variants of CD44 (CD44v), but not CD44s, form molecular aggregates in the plasma membrane. We demonstrate that reduction-sensitive dimerization of CD44v occurs, and also that larger aggregations of the protein can be stabilized by chemical cross-linking. Different CD44v proteins present on the same cell exclusively form homoaggregates. Molecular clustering does not require an intact cytoplasmic domain of the protein. The ability of cells to bind to soluble HA is upregulated more than one magnitude by the ectopic expression of CD44v4-v7, but only when the CD44v4-v7 protein forms intermolecular aggregates. Tunicamycin treatment inhibits HA binding by CD44v and at the same time destroys oligomerization. We propose that the regulation of clustering of CD44, mediated by factors including the presence of variant exons and glycosylation, allows cells in turn to regulate their HA binding properties.


Assuntos
Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/metabolismo , Processamento Alternativo/fisiologia , Animais , Membrana Celular/química , Membrana Celular/metabolismo , Reagentes de Ligações Cruzadas/farmacologia , Citoplasma/química , Dimerização , Eletroforese em Gel Bidimensional , Glicosilação , Receptores de Hialuronatos/química , Ácido Hialurônico/farmacologia , Oligopeptídeos/metabolismo , Neoplasias Pancreáticas , Ligação Proteica/fisiologia , Estrutura Terciária de Proteína , Ratos , Solubilidade , Células Tumorais Cultivadas/química , Células Tumorais Cultivadas/metabolismo
12.
J Clin Invest ; 102(5): 1024-34, 1998 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9727071

RESUMO

CD44 is important during myelopoiesis, although the contributions of variant CD44 proteins are unclear. We show here that in human long-term bone marrow culture antibodies recognizing a CD44 NH2-terminal epitope (mab 25-32) or a CD44v6 epitope (mab VFF18) inhibit myelopoiesis. However, mab 25-32 but not mab VFF18 affects myeloid colony formation. These data suggest that an early precursor cell compartment is the target for the 25-32 antibody, whereas the mab VFF18 targets later stages in myelopoiesis. Since the bulk of hemopoietic precursor cells are negative for the v6 epitope and only a minor subset of myeloid cells express the v6 epitope, we have used several human myeloid progenitor cell lines to unravel the function of different CD44 proteins. These cell lines produce variant CD44 proteins, predominantly a new variant CD44v4-v10, when stimulated towards myeloid differentiation. Features that can be acquired by the expression of CD44v4-v10 are an increased hyaluronate (HA) and a de novo chondroitin sulphate A (CS-A) binding. Although, the expression of CD44v4-v10 per se is necessary for HA and CS-A binding, the protein backbone seems to require appropriate glycosylation. HA binding results in CD44-mediated cellular self-aggregation and adhesion to the stromal cell line MS-5. In summary, our data suggest that different CD44 proteins are important for at least two different steps in myelopoiesis.


Assuntos
Células da Medula Óssea/metabolismo , Receptores de Hialuronatos/fisiologia , Leucopoese/fisiologia , Anticorpos/farmacologia , Adesão Celular/fisiologia , Diferenciação Celular/fisiologia , Linhagem Celular , Sulfatos de Condroitina/metabolismo , Células Clonais/metabolismo , Epitopos/imunologia , Citometria de Fluxo , Regulação da Expressão Gênica no Desenvolvimento/genética , Glicosilação , Humanos , Receptores de Hialuronatos/imunologia , Ácido Hialurônico/metabolismo , Ligação Proteica/fisiologia , RNA Mensageiro/metabolismo , Células-Tronco/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
13.
Mol Cell Biol ; 20(3): 912-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10629048

RESUMO

Extracellular matrix (ECM) formation and remodeling are critical processes for proper morphogenesis, organogenesis, and tissue repair. The proinflammatory cytokine tumor necrosis factor alpha (TNF-alpha) inhibits ECM accumulation by stimulating the expression of matrix proteolytic enzymes and by downregulating the deposition of structural macromolecules such as type I collagen. Stimulation of ECM degradation has been linked to prolonged activation of jun gene expression by the cytokine. Here we demonstrate that TNF-alpha inhibits transcription of the gene coding for the alpha2 chain of type I collagen [alpha2(I) collagen] in cultured fibroblasts by stimulating the synthesis and binding of repressive CCAAT/enhancer proteins (C/EBPs) to a previously identified TNF-alpha-responsive element. This conclusion was based on the concomitant identification of C/EBPbeta and C/EBPdelta as TNF-alpha-induced factors by biochemical purification and expression library screening. It was further supported by the ability of the C/EBP-specific dominant-negative (DN) protein to block TNF-alpha inhibition of alpha2(I) collagen but not TNF-alpha stimulation of the MMP-13 protease. The DN protein also blocked TNF-alpha downregulation of the gene coding for the alpha1 chain of type I collagen. The study therefore implicates repressive C/EBPs in the TNF-alpha-induced signaling pathway that controls ECM formation and remodeling.


Assuntos
Colágeno/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Nucleares/metabolismo , Transcrição Gênica/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Proteínas Estimuladoras de Ligação a CCAAT , Células Cultivadas , Colágeno/biossíntese , Colágeno Tipo I , Elementos Facilitadores Genéticos , Matriz Extracelular/fisiologia , Fibroblastos/fisiologia , Regulação da Expressão Gênica/fisiologia , Humanos , Cinética , Dados de Sequência Molecular , RNA Mensageiro/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/farmacologia , Fatores de Transcrição/metabolismo , Transfecção
14.
Reumatismo ; 59 Suppl 1: 13-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17828341

RESUMO

In the 1960s, Professor Verna Wright became increasingly interested in possible relationships between certain seronegative "variants of rheumatoid arthritis", as they were then generally known. At the Rheumatism Research Unit, a department within the division of medicine at Leeds University, he gathered around him a succession of research workers, whom he inspired to study aspects of these relationships. The focus was on family studies, as it was thought that genetic factors could be important. The striking association previously noted between sacroiliitis or full-blown ankylosing spondylitis and several of these disorders to be studied - e.g., psoriatic arthritis, ulcerative colitis, and the arthritis associated with Crohn's disease - was to be central for each of these studies. As a provisional collective name for these possibly related conditions, the term "Spondarthritides" was chosen. These were the days before HLA B27, and so the research tools were simply clinical, radiological (for sacroiliitis) and serological (for rheumatoid factor). The research programme confirmed not only links between the primary disorders with ankylosing spondylitis, but also links between the disorders themselves. Over subsequent years, the spondarthritis concept (dubbed by some "The Leeds Idea") has gained further strength from HLA studies internationally. And membership of the group of conditions fulfilling spondarthritis criteria has grown substantially. It is hoped that this now consolidated framework of spondylitis-related entities will pave the way for further research, with exciting prospects of gene-based prevention and/or cure through the increasing sophistication of molecular biology.


Assuntos
Sacroileíte/história , Espondilartrite/história , Artrite Psoriásica/história , Artrite Reumatoide/história , Biomarcadores , Colite Ulcerativa/história , Doença de Crohn/história , Antígeno HLA-B27/história , Teste de Histocompatibilidade/história , História do Século XX , História do Século XXI , Humanos , Fatores Imunológicos/história , Fator Reumatoide/história , Sacroileíte/imunologia , Espondilartrite/imunologia , Espondilite Anquilosante/história , Reino Unido
15.
Eur Psychiatry ; 45: 59-64, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28728096

RESUMO

BACKGROUND: There is contradictory evidence regarding negative memory biases in major depressive disorder (MDD) and whether these persist into remission, which would suggest their role as vulnerability traits rather than correlates of mood state. Early life stress (ELS), common in patients with psychiatric disorders, has independently been associated with memory biases, and confounds MDD versus control group comparisons. Furthermore, in most studies negative biases could have resulted from executive impairments rather than memory difficulties per se. METHODS: To investigate whether memory biases are relevant to MDD vulnerability and how they are influenced by ELS, we developed an associative recognition memory task for temporo-spatial contexts of social actions with low executive demands, which were matched across conditions (self-blame, other-blame, self-praise, other-praise). We included fifty-three medication-free remitted MDD (25 with ELS, 28 without) and 24 healthy control (HC) participants without ELS. RESULTS: Only MDD patients with ELS showed a reduced bias (accuracy/speed ratio) towards memory for positive vs. negative materials when compared with MDD without ELS and with HC participants; attenuated positive biases correlated with number of past major depressive episodes, but not current symptoms. There were no biases towards self-blaming or self-praising memories. CONCLUSIONS: This demonstrates that reduced positive biases in associative memory were specific to MDD patients with ELS rather than a general feature of MDD, and were associated with lifetime recurrence risk which may reflect a scarring effect. If replicated, our results would call for stratifying MDD patients by history of ELS when assessing and treating emotional memories.


Assuntos
Transtorno Depressivo Maior/psicologia , Controle Interno-Externo , Memória , Retenção Psicológica , Estresse Psicológico/psicologia , Adulto , Atenção , Estudos de Casos e Controles , Cognição , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autoimagem
16.
Cancer Res ; 56(13): 3134-41, 1996 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8674073

RESUMO

Several studies have demonstrated a correlation between the expression of CD44 variant isoforms and the ability of tumor cells to metastasize. The CD44 proteins carry amino acid sequence motifs that confer the ability to bind to the extracellular matrix component hyaluronate (HA). In this study, we investigated whether a CD44 variant previously shown to stimulate metastasis in a rat pancreatic carcinoma model (BSp73AS) is capable of binding to HA, and whether such binding is critical for metastasis. We show that transfection of this CD44 variant into BSp73AS cells increases the HA-binding capacity of the cells in a dose-dependent manner. Transfection of the same CD44 variant isoform into BDX2 cells also conferred strong HA-binding properties on these cells, but was insufficient to cause them to metastasize. Transfection of a surface-bound hyaluronidase into metastasizing BSp73AS cells bearing variant CD44 efficiently ablated the ability of these cells to bind to HA. However, in metastasis assays, these hyaluronidase-transfected cells showed patterns of metastasis similar to those of the parental cell line. We also show that the HA-binding capacity of a variety of tumor cells is not correlated with their metastatic proclivity, and that an antibody previously shown to block metastasis of the pancreatic carcinoma cells does not interfere with their ability to bind to HA. We conclude that although CD44 variant expression does promote metastasis formation, HA binding by tumor cells is not rate limiting for metastasis in the BSp73AS system and probably also in other metastasizing tumors. Furthermore, for metastasis by CD44 variant-expressing BSp73AS cells to occur, contact of the CD44 variant protein with a ligand other than HA Is required.


Assuntos
Receptores de Hialuronatos/biossíntese , Ácido Hialurônico/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Sequência de Aminoácidos , Animais , Anticorpos/farmacologia , Éxons , Receptores de Hialuronatos/genética , Isomerismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Metástase Neoplásica , Ratos , Ratos Endogâmicos , Células Tumorais Cultivadas
17.
Oncogene ; 6(5): 863-6, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1905006

RESUMO

A 886 bp cDNA encoding the murine rac1 protein has been isolated. The abundance of rac1 mRNA was determined in fourteen tissues from both mouse and pig. The mRNA 5' non-coding sequence is very rich in G + C, and has the potential to form several stable secondary structures. In addition, this region contains a putative open reading frame of 57 amino acids. Disruption of the actin microfilament network by cytochalasin B in LLC-PK1 cells results in down regulation of rac1 mRNA. In agreement with the proposed role of rac1 in exocytosis, these results could explain the inhibitory effect of cytochalasin B on secretory processes.


Assuntos
Citoesqueleto de Actina/fisiologia , Actinas/fisiologia , DNA/genética , Proteínas de Ligação ao GTP/genética , Regulação da Expressão Gênica , Citoesqueleto de Actina/ultraestrutura , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Colchicina/farmacologia , Citocalasina B/farmacologia , Citoesqueleto/efeitos dos fármacos , DNA/isolamento & purificação , Regulação da Expressão Gênica/efeitos dos fármacos , Biblioteca Gênica , Camundongos , Dados de Sequência Molecular , Nocodazol/farmacologia , Conformação de Ácido Nucleico , Sondas de Oligonucleotídeos , Especificidade de Órgãos , RNA Mensageiro/análise , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , Suínos , Proteínas rac de Ligação ao GTP
18.
Oncogene ; 7(11): 2175-87, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1279498

RESUMO

Transgenes encoding simian virus 40 (SV40) T antigen (Tag) can cause hyperplastic or tumorigenic lesions of desired but also of unforeseen cellular origin. Unexpectedly the human growth hormone-releasing factor (GRF) gene promoter directs expression of SV40 Tag specifically in thymic epithelial (TE) cells. Expression starts in the neonate, in which GRF-Tag+ cells display strict numerical and spatial constraints. Tag supersedes mechanisms that constrain these features and GRF-Tag mice develop thymic hyperplasia. To characterize GRF-Tag+ TE cells and their putative normal counterparts we compared phenotypic and functional effects caused by transgenes encoding mutant large T antigens. This strategy is applicable to any situation in which T antigen is used to alter development. One large Tag mutant (K1 + 5080) does not cause thymic hyperplasia. GRF-Tag (K1 + 5080)+ TE cells display strict temporal and spatial constraints throughout life. TE cells expressing other mutant large T antigens that cause thymic hyperplasia do not obey these rules and reveal that phenotypically distinct GRF-Tag+ TE-cell stages exist in vivo. Analysis of conditional immortal GRF-Tag(tsA58)+ TE cells expressing a temperature-sensitive large Tag shows that large Tag blocks differentiation in these cells. Phenotype and functions in these cells are regulated by cellular differentiation and interleukin 4 (IL-4).


Assuntos
Antígenos Transformantes de Poliomavirus/genética , Vírus 40 dos Símios/imunologia , Timo/citologia , Animais , Antígenos Transformantes de Poliomavirus/análise , Diferenciação Celular , Células Epiteliais , Hormônio Liberador de Hormônio do Crescimento/genética , Interleucina-4/farmacologia , Fator Estimulador de Colônias de Macrófagos/genética , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Fenótipo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-kit , Receptores de Interleucina-4 , Receptores Mitogênicos/genética , Temperatura
19.
Eur Psychiatry ; 30(4): 448-53, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25752724

RESUMO

BACKGROUND: One influential view is that vulnerability to major depressive disorder (MDD) is associated with a proneness to experience negative emotions in general. In contrast, blame attribution theories emphasise the importance of blaming oneself rather than others for negative events. Our previous exploratory study provided support for the attributional hypothesis that patients with remitted MDD show no overall bias towards negative emotions, but a selective bias towards emotions entailing self-blame relative to emotions that entail blaming others. More specifically, we found a decreased proneness for contempt/disgust towards others relative to oneself (i.e. self-contempt bias). Here, we report a definitive test of the competing general negative versus specific attributional bias theories of MDD. METHODS: We compared a medication-free remitted MDD (n=101) and a control group (n=70) with no family or personal history of MDD on a previously validated experimental test of moral emotions. The task measures proneness to specific emotions associated with different types of self-blame (guilt, shame, self-contempt/disgust, self-indignation/anger) and blame of others (other-indignation/anger, other-contempt/disgust) whilst controlling for the intensity of unpleasantness. RESULTS: We confirmed the hypothesis that patients with MDD exhibit an increased self-contempt bias with a reduction in contempt/disgust towards others. Furthermore, they also showed a decreased proneness for indignation/anger towards others. CONCLUSIONS: This corroborates the prediction that vulnerability to MDD is associated with an imbalance of specific self- and other-blaming emotions rather than a general increase in negative emotions. This has important implications for neurocognitive models and calls for novel focussed interventions to rebalance blame in MDD.


Assuntos
Ira , Transtorno Depressivo Maior/psicologia , Culpa , Autoimagem , Percepção Social , Adulto , Emoções , Feminino , Humanos , Controle Interno-Externo , Masculino , Pessoa de Meia-Idade , Inventário de Personalidade , Indução de Remissão , Adulto Jovem
20.
Protein Sci ; 10(3): 649-55, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11344333

RESUMO

We have designed a heterodimerizing leucine zipper system to target a radionuclide to prelocalized noninternalizing tumor-specific antibodies. The modular nature of the leucine zipper allows us to iteratively use design rules to achieve specific homodimer and heterodimer affinities. We present circular-dichroism thermal denaturation measurements on four pairs of heterodimerizing leucine zippers. These peptides are 47 amino acids long and contain four or five pairs of electrostatically attractive g <--> e' (i, i' +5) interhelical heterodimeric interactions. The most stable heterodimer consists of an acidic leucine zipper and a basic leucine zipper that melt as homodimers in the micro (T(m) = 28 degrees C) or nanomolar (T(m) = 40 degrees C) range, respectively, but heterodimerize with a T(m) >90 degrees C, calculated to represent femtamolar affinities. Modifications to this pair of acidic and basic zippers, designed to destabilize homodimerization, resulted in peptides that are unstructured monomers at 4 microM and 6 degrees C but that heterodimerize with a T(m) = 74 degrees C or K(d(37)) = 1.1 x 10(-11) M. A third heterodimerizing pair was designed to have a more neutral isoelectric focusing point (pI) and formed a heterodimer with T(m) = 73 degrees C. We can tailor this heterodimerizing system to achieve pharmacokinetics aimed at optimizing targeted killing of cancer cells.


Assuntos
Zíper de Leucina/genética , Peptídeos/genética , Sequência de Aminoácidos , Antineoplásicos/química , Dicroísmo Circular , Dimerização , Desenho de Fármacos , Estabilidade de Medicamentos , Ponto Isoelétrico , Dados de Sequência Molecular , Peptídeos/metabolismo , Desnaturação Proteica , Processamento de Proteína/genética , Quimera por Radiação/metabolismo , Radioimunoterapia , Eletricidade Estática , Termodinâmica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA