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1.
Acta Orthop ; 92(1): 102-108, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33103536

RESUMO

Background and purpose - Classification of ankle fractures is crucial for guiding treatment but advanced classifications such as the AO Foundation/Orthopedic Trauma Association (AO/OTA) are often too complex for human observers to learn and use. We have therefore investigated whether an automated algorithm that uses deep learning can learn to classify radiographs according to the new AO/OTA 2018 standards.Method - We trained a neural network based on the ResNet architecture on 4,941 radiographic ankle examinations. All images were classified according to the AO/OTA 2018 classification. A senior orthopedic surgeon (MG) then re-evaluated all images with fractures. We evaluated the network against a test set of 400 patients reviewed by 2 expert observers (MG, AS) independently.Results - In the training dataset, about half of the examinations contained fractures. The majority of the fractures were malleolar, of which the type B injuries represented almost 60% of the cases. Average area under the area under the receiver operating characteristic curve (AUC) was 0.90 (95% CI 0.82-0.94) for correctly classifying AO/OTA class where the most common major fractures, the malleolar type B fractures, reached an AUC of 0.93 (CI 0.90-0.95). The poorest performing type was malleolar A fractures, which included avulsions of the fibular tip.Interpretation - We found that a neural network could attain the required performance to aid with a detailed ankle fracture classification. This approach could be scaled up to other body parts. As the type of fracture is an important part of orthopedic decision-making, this is an important step toward computer-assisted decision-making.


Assuntos
Fraturas do Tornozelo/classificação , Fraturas do Tornozelo/diagnóstico por imagem , Aprendizado Profundo , Algoritmos , Humanos , Radiografia , Suécia
2.
Sci Technol Adv Mater ; 21(1): 205-218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32341720

RESUMO

The aim of this work is to investigate quench induced precipitation during continuous cooling in aluminium wrought alloys EN AW-7150 and EN AW-6082 using in situ synchrotron wide-angle X-ray scattering (WAXS). While X-ray diffraction is usually an ex situ method, a variety of diffraction patterns were recorded during the cooling process, allowing in situ analysis of the precipitation process. The high beam energy of about 100 keV allows the beam to penetrate a bulk sample with a 4 mm diameter in a quenching dilatometer. Additionally, the high intensity of a synchrotron source enables sufficiently high time resolution for fast in situ cooling experiments. Reaction peaks could be detected and compared with results from differential scanning calorimetry (DSC) by this method. A methodology is presented in this paper to evaluate WAXS data in a way that is directly comparable to DSC-experiments. The results show a high correlation between both techniques, DSC and WAXS, and can significantly improve continuous cooling precipitation diagrams.

3.
Oecologia ; 174(4): 1387-400, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24394862

RESUMO

Biodiversity experiments have shown that plant diversity has largely positive effects on insect diversity and abundance. However, such relationships have rarely been studied in undisturbed and more complex ecosystems such as forests. Flies (Diptera) are among the most dominant taxa in temperate ecosystems, influencing many ecosystem processes. As it is unknown how Diptera respond to changes in forest biodiversity, we examined how community characteristics of Diptera respond to varying levels of tree and herb diversity and vegetation structure. The study was conducted in the Hainich National Park (Central Germany) on 84 plots along a gradient of tree (from two to nine species) and herb (from two to 28 species) diversity. We found that herb and canopy cover as well as spatial effects were the best predictors of Diptera community composition, consisting of 62 families, including 99 Empidoidea and 78 Phoridae species. Abundance of Empidoidea was positively influenced by herb diversity, indicating bottom-up control. A complex causal pathway influenced Dipteran species richness: species-rich forest stands, with low beech cover, had lower canopy cover, resulting in higher Dipteran species richness. In addition, Diptera benefited from a more dense and diverse herb community. Individual species responded differentially to herb layer diversity, indicating that effects of plant diversity on higher trophic levels depend on species identity. We conclude that tree and herb canopy cover as well as herb diversity predominately shape Dipteran communities in temperate deciduous forests, which is in contrast to expectations from grassland studies exhibiting much closer relationships between plant and insect diversity.


Assuntos
Biodiversidade , Dípteros , Árvores , Animais , Ecossistema , Alemanha , Modelos Teóricos
4.
Nat Commun ; 15(1): 3081, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38594279

RESUMO

Tactile sensation and vision are often both utilized for the exploration of objects that are within reach though it is not known whether or how these two distinct sensory systems combine such information. Here in mice, we used a combination of stereo photogrammetry for 3D reconstruction of the whisker array, brain-wide anatomical tracing and functional connectivity analysis to explore the possibility of tacto-visual convergence in sensory space and within the circuitry of the primary visual cortex (VISp). Strikingly, we find that stimulation of the contralateral whisker array suppresses visually evoked activity in a tacto-visual sub-region of VISp whose visual space representation closely overlaps with the whisker search space. This suppression is mediated by local fast-spiking interneurons that receive a direct cortico-cortical input predominantly from layer 6 neurons located in the posterior primary somatosensory barrel cortex (SSp-bfd). These data demonstrate functional convergence within and between two primary sensory cortical areas for multisensory object detection and recognition.


Assuntos
Neurônios , Tato , Camundongos , Animais , Neurônios/fisiologia , Tato/fisiologia , Interneurônios , Reconhecimento Psicológico , Córtex Somatossensorial/fisiologia , Vibrissas/fisiologia
5.
Insects ; 13(11)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36354836

RESUMO

Seven species in the genus Medetera (Diptera: Dolichopodidae) are described here: Medetera aglaops sp. nov., Medetera corsicana sp. nov., Medetera gibbosipyga sp. nov., Medetera hispanica sp. nov., Medetera lusitana sp. nov., Medetera parva sp. nov., and Medetera rectipyga sp. nov. They all originate from the wider Mediterranean region in southwestern Europe (Iberian Peninsula, southern France, Corsica, Sardinia). The most striking feature in most of the species is the bi- or multicolour pattern of the eyes, most conspicuous in Medetera aglaops sp. nov. and Medetera lusitana sp. nov. This character is shared by the male and female sex and is thus not regarded as Male Secondary Sexual Character. All species belong to the Medetera apicalis species group sensu Bickel and are closely related based on shared characters in the hypandrium and cercus. Interestingly, three species with and four species without the basal pair of anterodorsal and posterodorsal bristles on the mid tibia are represented. This suggests that this diagnostic character has less phylogenetic relevance than previously anticipated. Unlike most Palaearctic Medetera, at least five of the new species are mostly found on rocky substrates in dry biotopes with a sclerophyllous vegetation. This further supports their relationship with species of the Medetera muralis subclade sensu Pollet, Germann and Bernasconi.

6.
Biol Lett ; 7(1): 11-4, 2011 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-20861035

RESUMO

A new dance fly (Empididae: Empidinae) with hugely modified male fore tarsus, either on the right, left, both or neither sides, is described from Japan. Such massive polymorphic asymmetry occurring with so high an incidence in a population is previously unreported. In view of the courtship behaviour of other Empidinae, we hypothesize that the oversized tarsus is a secondary sexual character employed by males for attracting females. Alternative hypotheses are also discussed. We suggest that this extraordinary new species is a potential model for the study of mating biology in Empidinae and the evolution of mating systems in general.


Assuntos
Dípteros/anatomia & histologia , Dípteros/classificação , Extremidades/anatomia & histologia , Animais , Feminino , Masculino , Comportamento Sexual Animal , Especificidade da Espécie
7.
Acta Orthop ; 82(1): 35-41, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21281259

RESUMO

BACKGROUND: We evaluated the accuracy and repeatability of a 3D method for polyethylene acetabular cup wear measurements using computed tomography (CT). We propose that the method be used for clinical in vivo assessment of wear in acetabular cups. MATERIAL AND METHODS: Ultra-high molecular weight polyethylene cups with a titanium mesh molded on the outside were subjected to wear using a hip simulator. Before and after wear, they were (1) imaged with a CT scanner using a phantom model device, (2) measured using a coordinate measurement machine (CMM), and (3) weighed. CMM was used as the reference method for measurement of femoral head penetration into the cup and for comparison with CT, and gravimetric measurements were used as a reference for both CT and CMM. Femoral head penetration and wear vector angle were studied. The head diameters were also measured with both CMM and CT. The repeatability of the method proposed was evaluated with two repeated measurements using different positions of the phantom in the CT scanner. RESULTS: The accuracy of the 3D CT method for evaluation of linear wear was 0.51 mm and the repeatability was 0.39 mm. Repeatability for wear vector angle was 17°. INTERPRETATION: This study of metal-meshed hip-simulated acetabular cups shows that CT has the capacity for reliable measurement of linear wear of acetabular cups at a clinically relevant level of accuracy.


Assuntos
Acetábulo , Prótese de Quadril , Teste de Materiais/métodos , Falha de Prótese , Materiais Biocompatíveis , Fenômenos Biomecânicos , Análise de Falha de Equipamento , Prótese de Quadril/efeitos adversos , Imageamento Tridimensional , Modelos Biológicos , Polietileno , Desenho de Prótese , Reprodutibilidade dos Testes , Estresse Mecânico , Propriedades de Superfície , Titânio , Tomografia Computadorizada por Raios X
8.
Materials (Basel) ; 14(4)2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33557276

RESUMO

Intermetallic γ-TiAl-based alloys are lightweight materials for high-temperature applications, e.g., in the aerospace and automotive industries. They can replace much heavier Ni-based alloys at operating temperatures up to 750 °C. Advanced variants of this alloy class enable processing routes that include hot forming. These alloys consist of three relevant crystallographic phases (γ-TiAl, α2-Ti3Al, ßo-TiAl) that transform into each other at different temperatures. For thermo-mechanical treatments as well as for adjusting alloy properties required under service conditions, the knowledge of the thermal expansion behavior of these phases is important. Therefore, thermal expansion coefficients were determined for the relevant phases in a Ti-Al-Nb-Mo alloy for temperatures up to 1100 °C using high-energy X-ray diffraction.

9.
Adv Mater ; 33(52): e2105096, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34632625

RESUMO

The grain size is a determinant microstructural feature to enable the activation of deformation twinning in hexagonal close-packed (hcp) metals. Although deformation twinning is one of the most effective mechanisms for improving the strength-ductility trade-off of structural alloys, its activation is reduced with decreasing grain size. This work reports the discovery of the activation of deformation twinning in a fine-grained hcp microstructure by introducing ductile body-centered cubic (bcc) nano-layer interfaces. The fast solidification and cooling conditions of laser-based additive manufacturing are exploited to obtain a fine microstructure that, coupled with an intensified intrinsic heat treatment, permits to generate the bcc nano-layers. In situ high-energy synchrotron X-ray diffraction allows tracking the activation and evolution of mechanical twinning in real-time. The findings obtained show the potential of ductile nano-layering for the novel design of hcp damage tolerant materials with improved life spans.

10.
Materials (Basel) ; 14(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34300775

RESUMO

Precipitation hardened and tempered martensitic-ferritic steels (TMFSs) are used in many areas of our daily lives as tools, components in power generation industries, or in the oil and gas (O&G) industry for creep and corrosion resistance. In addition to the metallurgical and forging processes, the unique properties of the materials in service are determined by the quality heat treatment (HT). By performing a quenching and partitioning HT during an in situ high energy synchrotron radiation experiment in a dilatometer, the evolution of retained austenite, martensite laths, dislocations, and carbides was characterized in detail. Atomic-scale studies on a specimen with the same HT subjected to a laser scanning confocal microscope show how dislocations facilitate cloud formation around carbides. These clouds have a discrete build-up, and thermodynamic calculations and density functional theory explain their stability.

11.
Zootaxa ; 4816(4): zootaxa.4816.4.5, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-33055686

RESUMO

Eucoryphus Mik is a Palaearctic genus of Dolichopodidae, previously with two described species confined to the montane and alpine zones of the European Alps. This paper describes a third species, Eucoryphus piscariviverus sp. nov., discovered in the mountains of southern Corsica. The systematic position of the genus Eucoryphus and the ecology of its species are discussed in detail and a key to males of the three species is provided.


Assuntos
Dípteros , Animais , França , Ilhas , Masculino
12.
Materials (Basel) ; 13(10)2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32455688

RESUMO

In situ dilatometry experiments using high energy synchrotron X-ray diffraction in transmission mode were carried out at the high energy material science beamline P07@PETRAIII at DESY (Deutsches Elektronen Synchrotron) for the tempering steel AISI 4140 at defined mechanical loading. The focus of this study was on the initial tempering state ( f e r r i t e ) and the hardened state ( m a r t e n s i t e ). Lattice strains were calculated from the 2D diffraction data for different h k l planes and from those temperature-dependent lattice plane specific diffraction elastic constants ( D E C s ) were determined. The resulting coupling terms allow for precise stress analysis for typical hypoeutectoid steels using diffraction data during heat treatment processes, that is, for in situ diffraction studies during thermal exposure. In addition, by averaging h k l specific Y o u n g ' s m o d u l i and P o i s s o n r a t i o s macroscopic temperature-dependent elastic constants were determined. In conclusion a novel approach for the determination of phase-specific temperature-dependent DECs was suggested using diffraction based dilatometry that provides more reliable data in comparison to conventional experimental procedures. Moreover, the averaging of lattice plane specific results from in situ diffraction analysis supply robust temperature-dependent macroscopic elastic constants for martensite and ferrite as input data for heat treatment process simulations.

13.
Int J Orthop Trauma Nurs ; 38: 100779, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32439319

RESUMO

INTRODUCTION: Hip fracture is common in the elderly and is associated with high comorbidity, mortality and complication rates. There has been an increase in the investigation of healthcare-related adverse events (AEs) in some patient groups but there is limited knowledge about hip fracture patients. The aim was to explore the incidence, preventability and nature of AEs in hip fracture patients. METHODS: One hundred and sixty three hip fracture patients participated. A record review was conducted of prospectively collected data using Global Trigger Tool methodology to identify AEs up to 90 days after surgery. RESULTS: Sixty two (38.0%) of 163 patients had at least one AE (range 1-7). One hundred and two AEs were identified and 62 (60.8%) were deemed preventable. Healthcare-associated infections e.g. pneumonia, urinary tract infections and pressure ulcers were common. AEs were more common in older patients and those with pre-existing health conditions. Fifty eight (56.9%) AEs caused temporary harm and 4 (3.9%) contributed to patient death. CONCLUSION: AEs are common in hip fracture patients and most are preventable. If the focus is on improving healthcare for these patients, we should be concentrating our efforts on reducing the number of these preventable AEs, with a particular emphasis on improving the care of older patients with pre-existing health conditions.


Assuntos
Fraturas do Quadril , Humanos , Incidência , Segurança do Paciente , Estudos Prospectivos
15.
Neurol Res ; 31(8): 873-7, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19215667

RESUMO

Gliosarcomas represent about 2% of glioblastoma multiforme (WHO grade IV). They have mixed features of glial and sarcomatous components. The clinical presentation and prognosis are similar to glioblastoma. Between 1997 and 2006, 16 patients with intracranial gliosarcoma were treated in the Department of Neurosurgery in Kiel, Germany. Median age was 63 years (52-79 years). Eleven patients were men and five were women. Six tumors were in the frontal lobe, four in the temporal lobe, three parietal, two in the thalamic area and one in the occipital lobe. Pre-operatively, in two patients, we could perform magnetic resonance (MR) spectroscopy. There was lactate peak, which is a sign of local necrosis and hypoxia. Median survival time in our patient group was 7 months (2-11 months). On histological examination, we found glial fibrillary acid protein positive cells surrounded by sarcomatous tissue and reticular fibers. The proliferation index MIB-1 was between 20 and 70%. The prognosis in this patient group is still poor. MR spectroscopy and location of the tumor adjacent to the dura with inhomogeneous contrast enhancement might give hints pre-operatively for the differential diagnosis of gliosarcoma. Further works with adjuvant chemotherapy are necessary.


Assuntos
Neoplasias Encefálicas/patologia , Encéfalo/patologia , Gliossarcoma/patologia , Idoso , Encéfalo/metabolismo , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/terapia , Proliferação de Células , Diagnóstico Diferencial , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Gliossarcoma/diagnóstico , Gliossarcoma/metabolismo , Gliossarcoma/terapia , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
16.
Cancer Res ; 67(9): 4190-8, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17483330

RESUMO

Retrospective studies of breast cancer patients suggest that primary tumor Her-2 overexpression or trastuzumab therapy is associated with a devastating complication: the development of central nervous system (brain) metastases. Herein, we present Her-2 expression trends from resected human brain metastases and data from an experimental brain metastasis assay, both indicative of a functional contribution of Her-2 to brain metastatic colonization. Of 124 archival resected brain metastases from breast cancer patients, 36.2% overexpressed Her-2, indicating an enrichment in the frequency of tumor Her-2 overexpression at this metastatic site. Using quantitative real-time PCR of laser capture microdissected epithelial cells, Her-2 and epidermal growth factor receptor (EGFR) mRNA levels in a cohort of 12 frozen brain metastases were increased up to 5- and 9-fold, respectively, over those of Her-2-amplified primary tumors. Co-overexpression of Her-2 and EGFR was also observed in a subset of brain metastases. We then tested the hypothesis that overexpression of Her-2 increases the colonization of breast cancer cells in the brain in vivo. A subclone of MDA-MB-231 human breast carcinoma cells that selectively metastasizes to brain (231-BR) overexpressed EGFR; 231-BR cells were transfected with low (4- to 8-fold) or high (22- to 28-fold) levels of Her-2. In vivo, in a model of brain metastasis, low or high Her-2-overexpressing 231-BR clones produced comparable numbers of micrometastases in the brain as control transfectants; however, the Her-2 transfectants yielded 3-fold greater large metastases (>50 microm(2); P < 0.001). Our data indicate that Her-2 overexpression increases the outgrowth of metastatic tumor cells in the brain in this model system.


Assuntos
Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/secundário , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Receptor ErbB-2/biossíntese , Animais , Neoplasias Encefálicas/genética , Neoplasias da Mama/genética , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptor ErbB-2/genética , Transfecção , Transplante Heterólogo
17.
Materials (Basel) ; 12(23)2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31795073

RESUMO

In situ synchrotron radiation diffraction was performed during the compression of as-cast Mg-3Nd-Zn alloys with different amounts (0, 0.5, 1, and 2 wt %) of Zn addition at room temperature. During the tests, the acoustic emission signals of the samples were recorded. The results show that the addition of Zn decreased the strength of the alloys but, at the same time, increased their ductility. In the earlier stages of deformation, twin formation and basal slip were the dominant deformation mechanisms. The twins tended to grow during the entire compression stage; however, the formation of new twins dominated only at the beginning of the plastic deformation. In order to accommodate the strain levels, the alloys containing Zn underwent nonbasal slip in the later stages of deformation. This can be attributed to the presence of precipitates containing Zn in the microstructure, inhibiting twin growth.

18.
Materials (Basel) ; 12(4)2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30791527

RESUMO

In this study, new multilayer TiAl-based composites were developed and characterized. The materials were produced by spark plasma sintering (SPS) of elemental Ti and Al foils and ceramic particles (TiB2 and TiC) at 1250 °C. The matrix of the composites consisted of α2-TiAl and γ-TiAl lamellas and reinforcing ceramic layers. Formation of the α2 + γ structure, which occurred via a number of solid⁻liquid and solid⁻solid reactions and intermediate phases, was characterized by in situ synchrotron X-ray diffraction analysis. The combination of X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) analysis revealed that an interaction of TiC with Ti and Al led to the formation of a Ti2AlC Mn+1AXn (MAX) phase. No chemical reactions between TiB2 and the matrix elements were observed. The microhardness, compressive strength, and creep behavior of the composites were measured to estimate their mechanical properties. The orientation of the layers with respect to the direction of the load affected the compressive strength and creep behavior of TiC-reinforced composites. The compressive strength of samples loaded in the perpendicular direction to layers was higher; however, the creep resistance was better for composites loaded in the longitudinal direction. The microhardness of the composites correlated with the microhardness of reinforcing components.

19.
Nanoscale ; 11(16): 7986-7995, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30969286

RESUMO

Nature uses self-assembly of a fairly limited selection of components to build hard and tough protective tissues like nacre and enamel. The resulting hierarchical micro/nanostructures provide decisive toughening mechanisms while preserving strength. However, to mimic microstructural and mechanical characteristics of natural materials in application-relevant synthetic nanostructures has proven to be difficult. Here, we demonstrate a biomimetic synthesis strategy, based on chemical vapour deposition technology, employed to fabricate a protective high-temperature resistant nanostructured ceramic TiAlN thin film with six levels of hierarchy. By using just two variants of gaseous precursors and through bottom-up self-assembly, an irregularly arranged hard and tough multilayer stack was formed, consisting of hard sublayers with herringbone micrograins, separated by tough interlayers with spherical nanograins, respectively composed of lamellar nanostructures of alternating coherent/incoherent, hard/tough, single-/poly-crystalline platelets. Micro- and nanomechanical testing, performed in situ in scanning and transmission electron microscopes, manifests intrinsic toughening mechanisms mediated by five types of interfaces resulting in intergranular, transgranular and cleavage fracture modes with zigzag-like crack patterns at multiple length-scales. The hierarchical 2.7 µm thick film self-assembled during ∼15 minutes of deposition time shows hardness, fracture stress and toughness of ∼31 GPa, ∼7.9 GPa and ∼4.7 MPa m0.5, respectively, as well as phase/microstructural thermal stability up to ∼950/900 °C. The film's microstructural and mechanical characteristics represent a milestone in the production of protective and wear-resistant thin films.

20.
Clin Exp Metastasis ; 25(7): 799-810, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18649117

RESUMO

Interactions between tumor cells and the microenvironment are crucial to tumor formation and metastasis. The central nervous system serves as a "sanctuary" site for metastasis, resulting in poor prognosis in diagnosed patients. The incidence of brain metastasis is increasing; however, little is known about interactions between the brain and metastatic cells. Brain pathology was examined in an experimental model system of brain metastasis, using a subline of MDA-MB-231 human breast cancer cells. The results were compared with an analysis of sixteen resected human brain metastases of breast cancer. Experimental metastases formed preferentially in specific brain regions, with a distribution similar to clinical cases. In both the 231-BR model, and in human specimens, Ki67 expression indicated that metastases were highly proliferative (approximately 50%). Little apoptosis was observed in either set of tumors. In the model system, metastases elicited a brain inflammatory response, with extensive reactive gliosis surrounding metastases. Similarly, large numbers of glial cells were found within the inner tumor mass of human brain metastases. In vitro co-cultures demonstrated that glia induced a approximately 5-fold increase in metastatic cell proliferation (P<0.001), suggesting that brain tissue secretes factors conducive to tumor cell growth. Molecules used to signal between tumor cells and the surrounding glia could provide a new avenue of therapeutic targets for brain metastases.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias da Mama/patologia , Neuroglia/fisiologia , Adulto , Idoso , Animais , Apoptose , Antígeno CD11b/análise , Movimento Celular , Proliferação de Células , Feminino , Humanos , Antígenos Comuns de Leucócito/análise , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade
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