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1.
Clin Cancer Res ; 30(20): 4743-4754, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39150543

RESUMO

PURPOSE: Large cell neuroendocrine carcinoma (LCNEC) is a high-grade neuroendocrine malignancy that, like small cell lung cancer (SCLC), is associated with the absence of druggable oncogenic drivers and dismal prognosis. In contrast to SCLC, however, there is little evidence to guide optimal treatment strategies, which are often adapted from SCLC and non-small cell lung cancer approaches. EXPERIMENTAL DESIGN: To better define the biology of LCNEC, we analyzed cell line and patient genomic data and performed IHC and single-cell RNA sequencing of core needle biopsies from patients with LCNEC and preclinical models. RESULTS: In this study, we demonstrate that the presence or absence of YAP1 distinguishes two subsets of LCNEC. The YAP1-high subset is mesenchymal and inflamed and is characterized, alongside TP53 mutations, by co-occurring alterations in CDKN2A/B and SMARCA4. Therapeutically, the YAP1-high subset demonstrates vulnerability to MEK- and AXL-targeting strategies, including a novel preclinical AXL chimeric antigen receptor-expressing T cell. Meanwhile, the YAP1-low subset is epithelial and immune-cold and more commonly features TP53 and RB1 co-mutations, similar to those observed in pure SCLC. Notably, the YAP1-low subset is also characterized by the expression of SCLC subtype-defining transcription factors, especially ASCL1 and NEUROD1, and as expected, given its transcriptional similarities to SCLC, exhibits putative vulnerabilities reminiscent of SCLC, including delta-like ligand 3 and CD56 targeting, as is with novel preclinical delta-like ligand 3 and CD56 chimeric antigen receptor-expressing T cells, and DNA damage repair inhibition. CONCLUSIONS: YAP1 defines distinct subsets of LCNEC with unique biology. These findings highlight the potential for YAP1 to guide personalized treatment strategies for LCNEC.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Carcinoma Neuroendócrino , Neoplasias Pulmonares , Fatores de Transcrição , Proteínas de Sinalização YAP , Humanos , Proteínas de Sinalização YAP/genética , Proteínas de Sinalização YAP/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/metabolismo , Linhagem Celular Tumoral , Carcinoma de Células Grandes/genética , Carcinoma de Células Grandes/patologia , Carcinoma de Células Grandes/metabolismo , Carcinoma de Células Grandes/terapia , Animais , Mutação , Biomarcadores Tumorais/genética , Camundongos , Regulação Neoplásica da Expressão Gênica , Prognóstico
2.
Knee ; 42: 28-36, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36863118

RESUMO

BACKGROUND: The aim of the present study is to describe the morphology and distribution of the nerve endings of the meniscotibial ligament (MTL) of the knee, in order to understand the interaction between the proprioceptive system and knee mechanics. METHODS: Twenty medial MTLs were obtained from deceased organ donors. The ligaments were measured, weighed and cut. Sections (10 mm) were prepared on hematoxylin and eosin-stained slides for analysis of tissue integrity, and 50 mm sections were submitted to immunofluorescence with the protein gene product (PGP) 9.5 as primary antibody and Alexa Fluor 488 as secondary antibody, followed by microscopic analysis. RESULTS: The medial MTL was identified in 100% of the dissections, with average length, width, thickness and weight of 7.07 ± 1.34 mm, 32.25 ± 3.09 mm, 3.53 ± 0.27 mm and 0.67 ± 0.13 g, respectively. The hematoxylin and eosin-stained histological sections exhibited typical ligament structure, with dense well-organized collagen fibers and vascular tissue. All the specimens analyzed contained type I (Ruffini) mechanoreceptors and free (type IV) nerve endings, varying from parallel to intertwined fibers. Nerve endings not classified with different irregular shapes were also found. Most type I mechanoreceptors were found close to the MTL insertions on the tibial plateau, while the free nerve endings were found adjacent to the capsule. CONCLUSION: The medial MTL showed a peripheral nerve structure, primarily type I and IV mechanoreceptors. These findings suggest that the medial MTL is important for proprioception and medial knee stabilization.


Assuntos
Mecanorreceptores , Terminações Nervosas , Humanos , Amarelo de Eosina-(YS)/metabolismo , Hematoxilina/metabolismo , Mecanorreceptores/metabolismo , Mecanorreceptores/patologia , Ligamentos Articulares
3.
Rev Bras Ortop (Sao Paulo) ; 56(4): 459-462, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34483389

RESUMO

Objective To evaluate the interobserver agreement of two classifications for floating knee: Fraser and Blake & McBryde. Method Thirty-two observers, subdivided according to the degree of titration (26 resident physicians and 6 orthopedic physicians specialized in orthopedic trauma), classified 15 fractures of the ipsilateral femur and tibia. Interobserver agreement was evaluated by using the Kappa coefficient . Result When evaluating the agreement between the 9 R1, a Kappa index of 0.58 was obtained for the Fraser classification and of 0.46 for the Blake & McBryde classification. Among the 7 R2, a rate of 0.59 was obtained for the Fraser rating and 0.51 for the Blake & McBryde rating. Among the 10 R3, the agreement index was higher for both classifications: 0.72 for the Fraser and 0.71 for the Blake & McBryde classification. Considering the 3 groups (R1, R2, R3) as one large group, the general Kappa index was calculated, which resulted in 0.63 for the Fraser classification and 0.56 for the Blake & McBryde classification. In the group of trauma and orthopedic knee specialists, in turn, an agreement of 0.597 was obtained for the Blake and McBryde classification and of 0.843 for the Fraser classification. Conclusion Comparatively, the two classifications presented a weak to moderate degree of agreement. Fraser classification had better agreement in both groups. The agreement was higher when evaluating orthopedic trauma physicians.

4.
Oecologia ; 192(2): 577-590, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31897723

RESUMO

Mutualistic interactions between plants and pollinators play an essential role in the organization and persistence of biodiversity. The structure of interaction networks mediates the resilience of local communities and ecosystem functioning to environmental changes. Hence, network structure conservation may be more critical for maintaining biodiversity and ecological services than the preservation of isolated species in changing landscapes. Here, we intensively surveyed seven 36 km2 landscapes to empirically investigate the effects of forest loss and landscape configuration on the structure of plant-pollinator networks in understory vegetation of Brazilian Atlantic Forest. Our results indicate that forest loss and isolation affect the structure of the plant-pollinator networks, which were smaller in deforested landscapes, and less specialized as patch isolation increased. Lower nestedness and degree of specialization (H'2) indicated that the remaining plant and bee species tend to be generalists, and many of the expected specialized interactions in the network were already lost. Because generalist species generate a cohesive interaction core in these networks, these simplified networks might be resistant to loss of peripheral species, but may be susceptible to the extinction of the most generalist species. We suggest that such a network pattern is an outcome of landscapes with a few remaining isolated patches of natural habitat. Our results add a new perspective to studies of plant-pollinator networks in fragmented landscapes, showing that those interaction networks might also be used to indicate how changes in natural habitat affect biodiversity and biotic interactions.


Assuntos
Ecossistema , Polinização , Animais , Abelhas , Brasil , Florestas , Plantas
5.
Rev Bras Ortop (Sao Paulo) ; 54(1): 73-77, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31363247

RESUMO

Humeral shaft fractures combined with elbow dislocation and fracture of the distal third of the bones of the forearm are uncommon. No description of this simultaneous association has been found in the same patient. Some studies report the association of these two lesions; however, no reports on the three ipsilateral lesions have been found at the PubMed, Lilacs and Bireme databases. The present report describes a case that occurred in a 13-year-old boy who suffered a fall from a height of approximately three meters and was admitted to a trauma hospital. Radiographs showed an ipsilateral humeral shaft fracture combined with elbow dislocation and a fracture of the distal-third of the bones of the forearm. Under general anesthesia, the injuries were readily reduced by closed manipulation, obtaining a satisfactory reduction of the injuries. Following this, an antebrachiopalmar splint and a commercial Velpeau shoulder immobilizer for the treatment of the humerus diaphyseal fracture were used. After 1 week, the patient presented non-alignment of the diaphyseal fracture of the humerus and was submitted to surgical treatment with flexible retrograde intramedullary nailing, antebrachiopalmar cast, and a commercial Velpeau shoulder immobilizer.

6.
Heart Lung Vessel ; 7(1): 47-53, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25861590

RESUMO

INTRODUCTION: Use of fibrinogen concentrate among cardiac anesthetists is growing especially for the benefits related to the reduction in the administration of bleeding and allogeneic blood components, which are exacerbated by cardiopulmonary bypass. Moreover, these products underwent complete viral inactivation, reducing the risks of contamination associated with transfusion. The purpose of this research was to review the literature looking for randomized controlled trials regarding fibrinogen concentrate and its benefits in cardiac surgery. METHOD: The papers used in this review were searched in BioMed Central, PubMed, Embase, and the Cochrane Central Register of Clinical Trial by two investigators. The full search strategy was performed to identify all randomized controlled trials in the last 10 years, comparing the use of fibrinogen in the adult treatment of perioperative bleeding to standard treatment or placebo. RESULTS: Only four articles matching the selection criteria for final analysis were identified and only 79 patients received therapy with fibrinogen concentrate in randomized trials performed in cardiac surgery. CONCLUSIONS: During the last 10 years, few randomized controlled trials were performed to confirm the real benefit of using lyophilized fibrinogen to reduce bleeding in cardiac surgery. However, when indicated, it may be a good option in order to reduce the consumption of blood products in the treatment of perioperative bleeding, following an algorithm based on point-of-care testing.

7.
Ambio ; 44(2): 154-62, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24973054

RESUMO

Ecological science contributes to solving a broad range of environmental problems. However, lack of ecological literacy in practice often limits application of this knowledge. In this paper, we highlight a critical but often overlooked demand on ecological literacy: to enable professionals of various careers to apply scientific knowledge when faced with environmental problems. Current university courses on ecology often fail to persuade students that ecological science provides important tools for environmental problem solving. We propose problem-based learning to improve the understanding of ecological science and its usefulness for real-world environmental issues that professionals in careers as diverse as engineering, public health, architecture, social sciences, or management will address. Courses should set clear learning objectives for cognitive skills they expect students to acquire. Thus, professionals in different fields will be enabled to improve environmental decision-making processes and to participate effectively in multidisciplinary work groups charged with tackling environmental issues.


Assuntos
Ecologia/educação , Ecologia/tendências , Resolução de Problemas , Aprendizagem Baseada em Problemas/tendências , Ecologia/normas , Humanos , Aprendizagem Baseada em Problemas/normas
8.
PLoS One ; 8(12): e82369, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24324776

RESUMO

Habitat loss is the main driver of the current biodiversity crisis, a landscape-scale process that affects the survival of spatially-structured populations. Although it is well-established that species responses to habitat loss can be abrupt, the existence of a biodiversity threshold is still the cause of much controversy in the literature and would require that most species respond similarly to the loss of native vegetation. Here we test the existence of a biodiversity threshold, i.e. an abrupt decline in species richness, with habitat loss. We draw on a spatially-replicated dataset on Atlantic forest small mammals, consisting of 16 sampling sites divided between forests and matrix habitats in each of five 3600-ha landscapes (varying from 5% to 45% forest cover), and on an a priori classification of species into habitat requirement categories (forest specialists, habitat generalists and open-area specialists). Forest specialists declined abruptly below 30% of forest cover, and spillover to the matrix occurred only in more forested landscapes. Generalists responded positively to landscape heterogeneity, peaking at intermediary levels of forest cover. Open area specialists dominated the matrix and did not spillover to forests. As a result of these distinct responses, we observed a biodiversity threshold for the small mammal community below 30% forest cover, and a peak in species richness just above this threshold. Our results highlight that cross habitat spillover may be asymmetrical and contingent on landscape context, occurring mainly from forests to the matrix and only in more forested landscapes. Moreover, they indicate the potential for biodiversity thresholds in human-modified landscapes, and the importance of landscape heterogeneity to biodiversity. Since forest loss affected not only the conservation value of forest patches, but also the potential for biodiversity-mediated services in anthropogenic habitats, our work indicates the importance of proactive measures to avoid human-modified landscapes to cross this threshold.


Assuntos
Biodiversidade , Ecossistema , Árvores , Brasil , Conservação dos Recursos Naturais , Meio Ambiente , Geografia
9.
J Plant Physiol ; 169(4): 421-8, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22196800

RESUMO

An essential step in the biosynthesis of bioactive brassinosteroids (BRs) in plants is the hydroxylation at C-22, a reaction catalyzed by P450 enzymes of the CYP90B and CYP724B subfamilies. Genes for both types of enzymes are present in many species, and in rice (Oryza sativa) and tomato (Solanum lycopersicum) both CYP90B and CYP724B enzymes contribute to C-22 hydroxylation. In Arabidopsis (Arabidopsis thaliana), C-22 hydroxylation of BRs is catalyzed by CYP90B1 (encoded by DWF4) and null dwf4 mutants show severe symptoms of BR-deficiency. CYP724A1 (At5g14400), an Arabidopsis gene of unknown function and limited expression, encodes a P450 sharing less than 55% sequence identity to CYP724B proteins. We used transgenic plants of the null mutants dwf4-102 and a novel allele, bashful (bsf), ectopically expressing the CYP724A1 gene to investigate the potential activity of CYP724A1 as a C-22 hydroxylase of BRs. Defects associated with BR deficiency were reversed and a normal growth habit restored in transgenic dwf4-102 and bsf plants overexpressing CYP724A1. The vegetative phase was prolonged and the transgenic plants were on average larger than wild type plants with respect to several morphometric parameters. Fertility was restored in the transgenic plants but individual siliques yielded fewer and heavier seeds than those of wild type plants. The implications of these findings with regard to the functions of CYP724A1 and the activity of its encoded enzyme are discussed.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Sistema Enzimático do Citocromo P-450/genética , Regulação da Expressão Gênica de Plantas/genética , Sequência de Aminoácidos , Arabidopsis/enzimologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Mapeamento Cromossômico , Clonagem Molecular , Códon sem Sentido , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/metabolismo , Expressão Gênica/genética , Dados de Sequência Molecular , Fenótipo , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Mutação Puntual , Alinhamento de Sequência , Análise de Sequência de DNA
10.
FEBS Lett ; 579(3): 783-91, 2005 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-15670847

RESUMO

The transition metal Zn is essential for many physiological processes in plants, yet at elevated concentrations this, and the related non-essential metal Cd, can be toxic. Arabidopsis thaliana HMA4, belonging to the Type P1B subfamily of P-type ATPases, has recently been implicated in Zn nutrition, having a role in root to shoot Zn translocation. Using Arabidopsis insertional mutants, it is shown here that disruption of AtHMA4 function also results in increased sensitivity to elevated levels of Cd and Zn, suggesting that AtHMA4 serves an important role in metal detoxification at higher metal concentrations. AtHMA4 and a truncated form lacking the last 457 amino acids both confer Cd and Zn resistance to yeast but a mutant version of the full-length AtHMA4 (AtHMA4-C357G) does not; this demonstrates that the C-terminal region is not essential for this function. Evidence is presented that AtHMA4 functions as an efflux pump.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Cádmio/metabolismo , Zinco/metabolismo , Adenosina Trifosfatases/química , Adenosina Trifosfatases/genética , Sequência de Aminoácidos , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Sequência de Bases , Transporte Biológico , Primers do DNA , Dados de Sequência Molecular , Saccharomyces cerevisiae/metabolismo , Homologia de Sequência de Aminoácidos
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