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1.
Science ; 368(6493): 897-901, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32381591

RESUMO

Cytotoxic T lymphocytes (CTLs) kill infected and cancerous cells. We detected transfer of cytotoxic multiprotein complexes, called supramolecular attack particles (SMAPs), from CTLs to target cells. SMAPs were rapidly released from CTLs and were autonomously cytotoxic. Mass spectrometry, immunochemical analysis, and CRISPR editing identified a carboxyl-terminal fragment of thrombospondin-1 as an unexpected SMAP component that contributed to target killing. Direct stochastic optical reconstruction microscopy resolved a cytotoxic core surrounded by a thrombospondin-1 shell of ~120 nanometer diameter. Cryo-soft x-ray tomography analysis revealed that SMAPs had a carbon-dense shell and were stored in multicore granules. We propose that SMAPs are autonomous extracellular killing entities that deliver cytotoxic cargo targeted by the specificity of shell components.


Assuntos
Citotoxicidade Imunológica , Granzimas/metabolismo , Complexos Multiproteicos/metabolismo , Perforina/metabolismo , Linfócitos T Citotóxicos/metabolismo , Trombospondina 1/metabolismo , Sistemas CRISPR-Cas , Exocitose , Edição de Genes , Humanos , Células K562 , Trombospondina 1/genética , Tomografia por Raios X
2.
Nat Biomed Eng ; 4(3): 257-258, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32165728
3.
Chin Med J (Engl) ; 133(9): 1015-1024, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32004165

RESUMO

BACKGROUND: Human infections with zoonotic coronaviruses (CoVs), including severe acute respiratory syndrome (SARS)-CoV and Middle East respiratory syndrome (MERS)-CoV, have raised great public health concern globally. Here, we report a novel bat-origin CoV causing severe and fatal pneumonia in humans. METHODS: We collected clinical data and bronchoalveolar lavage (BAL) specimens from five patients with severe pneumonia from Wuhan Jinyintan Hospital, Hubei province, China. Nucleic acids of the BAL were extracted and subjected to next-generation sequencing. Virus isolation was carried out, and maximum-likelihood phylogenetic trees were constructed. RESULTS: Five patients hospitalized from December 18 to December 29, 2019 presented with fever, cough, and dyspnea accompanied by complications of acute respiratory distress syndrome. Chest radiography revealed diffuse opacities and consolidation. One of these patients died. Sequence results revealed the presence of a previously unknown ß-CoV strain in all five patients, with 99.8% to 99.9% nucleotide identities among the isolates. These isolates showed 79.0% nucleotide identity with the sequence of SARS-CoV (GenBank NC_004718) and 51.8% identity with the sequence of MERS-CoV (GenBank NC_019843). The virus is phylogenetically closest to a bat SARS-like CoV (SL-ZC45, GenBank MG772933) with 87.6% to 87.7% nucleotide identity, but is in a separate clade. Moreover, these viruses have a single intact open reading frame gene 8, as a further indicator of bat-origin CoVs. However, the amino acid sequence of the tentative receptor-binding domain resembles that of SARS-CoV, indicating that these viruses might use the same receptor. CONCLUSION: A novel bat-borne CoV was identified that is associated with severe and fatal respiratory disease in humans.


Assuntos
Betacoronavirus , Infecções por Coronavirus/virologia , Pneumonia Viral/virologia , Adulto , Idoso , Betacoronavirus/genética , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/terapia , Tomografia por Raios X , Resultado do Tratamento
4.
PLoS One ; 15(1): e0227601, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31978064

RESUMO

The diversity of living cells, in both size and internal complexity, calls for imaging methods with adaptable spatial resolution. Soft x-ray tomography (SXT) is a three-dimensional imaging technique ideally suited to visualizing and quantifying the internal organization of single cells of varying sizes in a near-native state. The achievable resolution of the soft x-ray microscope is largely determined by the objective lens, but switching between objectives is extremely time-consuming and typically undertaken only during microscope maintenance procedures. Since the resolution of the optic is inversely proportional to the depth of focus, an optic capable of imaging the thickest cells is routinely selected. This unnecessarily limits the achievable resolution in smaller cells and eliminates the ability to obtain high-resolution images of regions of interest in larger cells. Here, we describe developments to overcome this shortfall and allow selection of microscope optics best suited to the specimen characteristics and data requirements. We demonstrate that switchable objective capability advances the flexibility of SXT to enable imaging cells ranging in size from bacteria to yeast and mammalian cells without physically modifying the microscope, and we demonstrate the use of this technology to image the same specimen with both optics.


Assuntos
Imageamento Tridimensional/métodos , Análise de Célula Única/métodos , Tomografia por Raios X/instrumentação , Tomografia por Raios X/métodos , Linfócitos B/citologia , Desenho de Equipamento , Escherichia coli/citologia , Humanos , Schizosaccharomyces/citologia , Análise de Célula Única/instrumentação
5.
Sci Total Environ ; 713: 136510, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31958721

RESUMO

French Vertical Flow (VF) treatment wetlands receive raw wastewater and provide simultaneous sludge and wastewater treatment. For proper sludge handling, the treatment wetland must be designed adequately and specific operational conditions must be maintained. When these conditions are not met, accumulation of biosolids may lead to clogging. Filtration in French VF Treatment wetlands is governed by mechanisms at the pore-scale. They must be better understood to predict reliably biosolid accumulation. X-ray Computed Tomography (Xray-CT) is a promising technique to characterize in detail the morphology of the filtering media in treatment wetlands. In order to set a solid basis for the use of Xray-CT, the spatial representativity of measurements must be assessed. This issue is addressed in this study by successively analyzing spatial properties at the filter scale using Frequency Domain Electromagnetic Measurements (FDEMs), and at the pore scale using Xray-CT. A map of the electric conductivity at the surface of a French VF Treatment wetland is obtained by FDEM that indicates a homogeneous distribution of biosolids to which electrical conductivity is highly correlated. Different morphological properties were computed from Xray-CT after phase segmentation: phase volume fraction profiles, Specific Surface Area profiles and pore size distributions. Samples show several similarities of pore scale properties obtained by Xray-CT independently of the sampling region and especially the same vertical gradients. FDEM measurements and Xray-CT analysis are in agreement to indicate a good influent distribution at the surface of a full-scale mature French VF Treatment wetland. A criterion to define the limits of the deposit layer and gravel layer is introduced. This division allows to compare layers independently. Finally, a 2D-REV analysis suggests that the selected sample diameter of 5 cm is large enough to be representative of the heterogeneous distribution of phases at the pore-scale as long as no Phragmites are present.


Assuntos
Áreas Alagadas , Tomografia por Raios X , Eliminação de Resíduos Líquidos , Águas Residuárias
6.
Nat Biomed Eng ; 4(3): 343-354, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31768001

RESUMO

Imaging techniques for quantifying changes in the hierarchical structure of deforming joints are constrained by destructive sample treatments, sample-size restrictions and lengthy scan times. Here, we report the use of fast low-dose pink-beam synchrotron X-ray tomography in combination with mechanical loading at nanometric precision for in situ imaging, at resolutions below 100 nm, of the mechanical strain in intact untreated joints under physiologically realistic conditions. We show that in young, older and osteoarthritic mice, hierarchical changes in tissue structure and mechanical behaviour can be simultaneously visualized, and that the tissue structure at the cellular level correlates with the mechanical performance of the whole joint. We also use the tomographic approach to study the colocalization of tissue strains to specific chondrocyte lacunar organizations within intact loaded joints and to explore the role of calcified-cartilage stiffness on the biomechanics of healthy and pathological joints.


Assuntos
Articulações/diagnóstico por imagem , Síncrotrons , Tomografia por Raios X/métodos , Animais , Condrócitos/ultraestrutura , Imageamento Tridimensional , Articulações/ultraestrutura , Masculino , Camundongos , Nanoestruturas , Osteoartrite/diagnóstico por imagem , Osteoartrite/patologia , Estresse Mecânico
7.
J Pediatr Orthop ; 40(1): 42-47, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31815861

RESUMO

BACKGROUND: Several authors mentioned surgical outcome for scoliosis associated with neurofibromatosis type 1 (NF-1). However, no studies have summarized long-term surgical outcomes after surgical treatment of early-onset scoliosis (EOS) with NF-1. The purpose of this study is to evaluate the long-term surgical outcome after early definitive spinal fusion for EOS in NF-1 patients. METHODS: We performed a retrospective review on a cohort of 11 patients diagnosed with EOS associated with NF-1 between 1990 and 2009 in our hospital. The study included 7 male and 4 female NF-1 patients with a mean age at fusion surgery of 8 years 4 months who underwent early definitive spinal fusion for EOS. We reviewed radiographs, computed tomography and magnetic resonance images for each patient. The data collected included type of NF-1, Cobb angles, kyphotic angle, spinal length (T1-S1), and pulmonary function. We also evaluated progression of the dystrophic change through radiographs and computed tomography during the follow-up period. RESULTS: The mean follow-up duration was 14 years (5 y 10 mo to 25 y). All patients underwent anterior and posterior fusion surgeries in either 1 or 2 stages. Seven cases had subtotal tumor resection from the concave side followed by rib strut grafting. The mean preoperative Cobb angle of the primary curve was corrected from 71.2 to 24.1 degrees and was maintained at the final follow-up at 23.5 degrees. Mean values for preoperative and final follow-up T1-S1 heights were 30.7 and 36.2 cm, respectively. Mean values for preoperative and final follow-up % forced vital capacity (the present/the predicted) were 75.0% and 74.4%, respectively. The dystrophic change progressed in all cases during the long-term follow-up. CONCLUSIONS: Our goals for NF-1 scoliosis are to obtain deformity correction, to achieve stable instrumentation by using longer fusion levels and to attain a solid fusion mass that can tolerate continual erosion during the long-term follow-up. We achieve this by using a circumferential approach for EOS associated with NF-1. LEVEL OF EVIDENCE: Level IV-case series.


Assuntos
Neurofibromatose 1/complicações , Escoliose/complicações , Escoliose/cirurgia , Fusão Vertebral , Adolescente , Adulto , Criança , Pré-Escolar , Progressão da Doença , Feminino , Seguimentos , Humanos , Cifose/diagnóstico por imagem , Cifose/cirurgia , Imagem por Ressonância Magnética , Masculino , Neurofibromatose 1/cirurgia , Estudos Retrospectivos , Escoliose/diagnóstico por imagem , Escoliose/fisiopatologia , Fusão Vertebral/métodos , Fatores de Tempo , Tomografia por Raios X , Resultado do Tratamento , Capacidade Vital , Adulto Jovem
8.
Radiologe ; 60(2): 162-168, 2020 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-31858158

RESUMO

BACKGROUND: Before performing a medical procedure, such as a computed tomography, an obligatory informed consent of the patient and its detailed documentation is necessary. METHODS: A total of 1424 informed consent forms for contrast-enhanced computed tomography from four clinics with different healthcare levels were analyzed. Informed consent forms were evaluated related to completeness, legibility and quality. RESULTS: In all, 1110 (77.9%) informed consent forms were sufficiently completed, 267 patients (18.8%) answered the form incompletely and 47 patients (3.3%) returned it without answering a question. Handwritten comments were found in 1391 (97.7%) cases. Thereof, 1329 (93.3%) were graded as detailed comments and 62 (4.4%) as less detailed comments. These comments were well legible in 675 (47.4%) cases, 558 (39.2%) informed consents showed limited legibility and in 158 (11.1%) more than 50% of the comments were unreadable. Signatures were complete in 1374 (96.5%) informed consent forms. CONCLUSION: The results show a better quality and documentation of informed consent forms for computed tomography obtained by radiology residents compared to radiological specialists. Compared to the radiologists, the non-radiologists performed significantly worse. The establishment of videos and use of digital informed consent forms could provide a possible solution.


Assuntos
Termos de Consentimento , Confiabilidade dos Dados , Tomografia por Raios X , Documentação , Humanos , Consentimento Livre e Esclarecido , Estudos Retrospectivos
9.
Medicina (B Aires) ; 79(6): 506-508, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31829954

RESUMO

The arteriovenous extracorporeal membrane is used in patients with hemodynamic and respiratory failure, unresponsive to conventional treatment. It provides transitory hemodynamic support, oxygenation and removal of CO2, allowing pulmonary rest. Moreover it offers the possibility of ultraprotective ventilation and avoids generation of VILI (Ventilation-Induced Lung Injury). It is not frequently used in patients with hemodynamic failure secondary to obstructive shock due to mediastinal compromise. We present the case of a patient with obstructive shock, mediastinal mass of lymphoproliferative origin that was treated with extracorporeal arteriovenous circulation membrane.


Assuntos
Oxigenação por Membrana Extracorpórea/métodos , Linfoma Difuso de Grandes Células B/complicações , Insuficiência Respiratória/terapia , Choque Cardiogênico/etiologia , Choque Cardiogênico/terapia , Adulto , Angiografia por Tomografia Computadorizada/métodos , Feminino , Hemodinâmica , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/patologia , Choque Cardiogênico/diagnóstico por imagem , Tomografia por Raios X/métodos , Resultado do Tratamento
10.
Monaldi Arch Chest Dis ; 89(3)2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31558004

RESUMO

Pleural effusion is easily diagnosed often managed optimally with standard protocols. It at times, is a diagnostic dilemma as it comes with big list of differential diagnosis. Pleural effusion due to pancreaticopleural fistula (PPF) is a rare and on right side is even rarer. Detailed history along with high index of suspicion in required to diagnose PPF, which is confirmed by increased level of pleural fluid amylase and lipase along with magnetic resonance cholangiopancreatography (MRCP) or endoscopic retrograde cholangiopancreatography (ERCP) demonstrating fistula tract. Here we report the case of a young patient who presented with respiratory distress and was wrongly diagnosed as right sided tubercular effusion which later turned out to be pancreatic effusion. Management in our case was multi-disciplinary involving pulmonologist, gastroenterologist, radiologist and thoracic surgeon.


Assuntos
Fístula Pancreática/complicações , Pancreatite Crônica/patologia , Derrame Pleural/etiologia , Adulto , Calcinose , Colangiopancreatografia Retrógrada Endoscópica/métodos , Diagnóstico Diferencial , Humanos , Imagem por Ressonância Magnética , Masculino , Pâncreas/patologia , Fístula Pancreática/diagnóstico por imagem , Pancreatite Crônica/diagnóstico por imagem , Pancreatite Crônica/enzimologia , Derrame Pleural/diagnóstico por imagem , Derrame Pleural/patologia , Cirurgia Torácica Vídeoassistida/métodos , Tomografia por Raios X , Resultado do Tratamento
11.
Methods Mol Biol ; 1998: 129-148, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31250299

RESUMO

The ESCRT machinery mediates scission of the intercellular bridge that connects two daughter cells at the end of cytokinesis. Structured illumination microscopy (SIM) and cryo-soft-X-ray tomography (cryo-SXT) have been used in recent years to study the topology of ESCRT-driven cytokinetic abscission. These studies revealed that the intercellular bridge is occupied by cortical rings and spiral-like filaments and that ESCRTs form ring-like structures in this region during abscission. In this chapter, we provide two protocols: a protocol for determining the spatial organization of specific ESCRT components at the intercellular bridge using SIM and a protocol for resolving the ultrastructural organization of cortical filaments at the intercellular bridge using cryo-SXT.


Assuntos
Microscopia Crioeletrônica/métodos , Citocinese , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Microscopia Intravital/métodos , Tomografia por Raios X/métodos , Animais , Cães , Genes Reporter/genética , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Células HeLa , Humanos , Substâncias Luminescentes/química , Células Madin Darby de Rim Canino , Imagem Óptica/métodos
12.
Environ Pollut ; 252(Pt A): 155-162, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31146230

RESUMO

Sewage sludge contains Ag2S-NPs causing NP exposure of soil fauna when sludge is applied as soil amendment. Earthworm bioturbation is an important process affecting many soil functions. Bioturbation may be affected by the presence of Ag2S-NPs, but the earthworm activity itself may also influence the displacement of these NPs that otherwise show little transport in the soil. The aim of this study was to determine effects of Ag2S-NPs on earthworm bioturbation and effect of this bioturbation on the vertical distribution of Ag2S-NPs. Columns (12 cm) of a sandy loamy soil with and without Lumbricus rubellus were prepared with and without 10 mg Ag kg-1, applied as Ag2S-NPs in the top 2 cm of the soil, while artificial rainwater was applied at ∼1.2 mm day-1. The soil columns were sampled at three depths weekly for 28 days and leachate collected from the bottom. Total Ag measurements showed more displacement of Ag to deeper soil layers in the columns with earthworms. The application of rain only did not significantly affect Ag transport in the soil. No Ag was detected in column leachates. X-ray tomography showed that changes in macro porosity and pore size distribution as a result of bioturbation were not different between columns with and without Ag2S-NPs. Earthworm activity was therefore not affected by Ag2S-NPs at the used exposure concentration. Ag concentrations along the columns and the earthworm density allowed the calculation of the bioturbation rate. The effect on the Ag transport in the soil shows that earthworm burrowing activity is a relevant process that must be taken into account when studying the fate of nanoparticles in soils.


Assuntos
Nanopartículas Metálicas/química , Oligoquetos/metabolismo , Prata/análise , Poluentes do Solo/análise , Solo/química , Animais , Esgotos/química , Tomografia por Raios X
13.
Biochem Soc Trans ; 47(2): 489-508, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30952801

RESUMO

Morphometric measurements, such as quantifying cell shape, characterizing sub-cellular organization, and probing cell-cell interactions, are fundamental in cell biology and clinical medicine. Until quite recently, the main source of morphometric data on cells has been light- and electron-based microscope images. However, many technological advances have propelled X-ray microscopy into becoming another source of high-quality morphometric information. Here, we review the status of X-ray microscopy as a quantitative biological imaging modality. We also describe the combination of X-ray microscopy data with information from other modalities to generate polychromatic views of biological systems. For example, the amalgamation of molecular localization data, from fluorescence microscopy or spectromicroscopy, with structural information from X-ray tomography. This combination of data from the same specimen generates a more complete picture of the system than that can be obtained by a single microscopy method. Such multimodal combinations greatly enhance our understanding of biology by combining physiological and morphological data to create models that more accurately reflect the complexities of life.


Assuntos
Tomografia por Raios X/métodos , Humanos , Microscopia Eletrônica , Microscopia de Fluorescência/métodos , Imagem Multimodal/métodos
14.
Ultramicroscopy ; 201: 58-67, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30928781

RESUMO

Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) can provide unrivalled high-resolution images of specific features and volumes of interest. However, the regions interrogated are typically very small, and sample preparation is both time-consuming and destructive. Here we consider how prior X-ray micro-computed tomography (microCT) presents an opportunity to increase the efficiency of electron microscopy in biology. We demonstrate how it can be used to; select the most promising samples and target site-specific locations; provide a wider context of the location being interrogated (multiscale correlative imaging); guide sample preparation and 3D imaging schemes; as well as quantify the effects of destructive sample preparation and staining procedures. We present a workflow utilising open source software in which microCT can be used either broadly, or precisely, to experimentally steer and inform subsequent electron microscopy studies. As automated sample registration procedures are developed to enable correlative microscopy, experimental steering by prior CT could be beneficially routinely incorporated into many experimental workflows.


Assuntos
Tomografia com Microscopia Eletrônica/métodos , Microscopia Eletrônica de Transmissão/métodos , Tomografia por Raios X/métodos , Imageamento Tridimensional/métodos , Microscopia Eletrônica de Varredura/métodos , Software , Microtomografia por Raio-X/métodos
15.
Facial Plast Surg ; 35(1): 3-8, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30759455

RESUMO

Successful functional surgery on the nasal framework requires reliable and comprehensive diagnosis. In this regard, the authors introduce a new methodology: Digital Analysis of Nasal Airflow (diANA). It is based on computational fluid dynamics, a statistical shape model of the healthy nasal cavity and rhinologic expertise. diANA necessitates an anonymized tomographic dataset of the paranasal sinuses including the complete nasal cavity and, when available, clinical information. The principle of diANA is to compare the morphology and the respective airflow of an individual nose with those of a reference. This enables morphometric aberrations and consecutive flow field anomalies to localize and quantify within a patient's nasal cavity. Finally, an elaborated expert opinion with instructive visualizations is provided. Using diANA might support surgeons in decision-making, avoiding unnecessary surgery, gaining more precision, and target-orientation for indicated operations.


Assuntos
Simulação por Computador , Cavidade Nasal/diagnóstico por imagem , Obstrução Nasal/cirurgia , Seios Paranasais/diagnóstico por imagem , Adulto , Tomada de Decisão Clínica , Técnicas de Apoio para a Decisão , Feminino , Humanos , Hidrodinâmica , Modelos Anatômicos , Modelos Estatísticos , Obstrução Nasal/fisiopatologia , Respiração , Tomografia por Raios X
16.
Microsc Res Tech ; 82(6): 812-848, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30786098

RESUMO

X-ray computed tomography is a strong tool that finds many applications both in medical applications and in the investigation of biological and nonbiological samples. In the clinics, X-ray tomography is widely used for diagnostic purposes whose three-dimensional imaging in high resolution helps physicians to obtain detailed image of investigated regions. Researchers in biological sciences and engineering use X-ray tomography because it is a nondestructive method to assess the structure of their samples. In both medical and biological applications, visualization of soft tissues and structures requires special treatment, in which special contrast agents are used. In this detailed report, molecule-based and nanoparticle-based contrast agents used in biological applications to enhance the image quality were compiled and reported. Special contrast agent applications and protocols to enhance the contrast for the biological applications and works to develop nanoparticle contrast agents to enhance the contrast for targeted drug delivery and general imaging applications were also assessed and listed.


Assuntos
Meios de Contraste/administração & dosagem , Meios de Contraste/farmacologia , Tomografia por Raios X/métodos , Animais , Humanos
17.
Mater Sci Eng C Mater Biol Appl ; 97: 336-346, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30678919

RESUMO

Scaffolds for bone tissue engineering require a combination of bioactivity and bioresorption at the sample surface and high mechanical properties in the bulk. This work presents a novel calcium phosphate (CaP)/polycaprolactone (PCL) scaffold with graded composition and porosity fraction. The scaffold is made of (i) a dense hydroxyapatite (HA)/ß-tricalcium phosphate (ß-TCP) core, (ii) a macroporous HA/ß-TCP transition layer and (iii) a macroporous PCL/(HA/ß-TCP) external layer. The ceramic layers were fabricated by gel-casting whereas the outer composite layer was obtained by a solvent casting/particle leaching process. The microstructure, phase composition and biodegradation of the scaffolds were characterized. The gradient of porosity was clearly obtained whereas the gradation of phase composition was less pronounced. An in vitro dissolution test was performed by immersing the scaffolds in a TRIS solution. The results showed a dissolution phenomenon with possible differentiated mechanisms in the different layers, in relation with the targeted multi-functionality.


Assuntos
Fosfatos de Cálcio/química , Poliésteres/química , Tecidos Suporte , Materiais Biocompatíveis/química , Cerâmica/química , Microscopia Eletrônica de Varredura , Porosidade , Pós/química , Termogravimetria , Tomografia por Raios X , Difração de Raios X
18.
Int J Clin Oncol ; 24(4): 385-393, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30374687

RESUMO

BACKGROUND: For thymic epithelial tumors (TETs), the National Comprehensive Cancer Network guideline has suggested that complete excision of the tumor should be performed without a preoperative biopsy when resectable. However, little evidence has been provided to support this strategy. The purpose of this study was to review our diagnostic process and to evaluate the validity of radical resection of anterior mediastinal masses (AMMs) without pathological confirmation. METHODS: A total of 254 patients underwent surgical resection for AMMs between 2004 and 2015. This study included 181 patients with likely TETs according to clinical features, serum levels of tumor markers and autoimmune-antibodies, and radiological findings. In addition, AMMs likely TETs were classified into resectable or unresectable tumors. We retrospectively reviewed the diagnostic process of those patients and validated surgical resection of AMMs without a definitive diagnosis. RESULTS: Among 254 patients, 181 were suspected of having a TET based on the serum levels of tumor markers and autoimmune-antibodies and the radiological findings. Of them, 157 patients were deemed resectable and underwent surgical resection without histological confirmation, and 144 (92%) were diagnosed with TETs in the final pathological examinations. In 13 patients with non-TETs, the tumors were difficult to differentiate from TETs by imaging and clinical findings alone. CONCLUSIONS: A total of 92% of patients suspected of having a TET and who underwent complete resection without pathological confirmation were accurately diagnosed and properly treated. Surgical resection without a definitive diagnosis was feasible in patients suspected of having a TET when they were considered resectable.


Assuntos
Neoplasias do Mediastino/diagnóstico , Neoplasias Epiteliais e Glandulares/diagnóstico , Neoplasias do Timo/diagnóstico , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/sangue , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Neoplasias do Mediastino/patologia , Neoplasias do Mediastino/cirurgia , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Epiteliais e Glandulares/cirurgia , Estudos Retrospectivos , Neoplasias do Timo/patologia , Neoplasias do Timo/cirurgia , Tomografia por Raios X
19.
Laryngoscope ; 129(11): 2603-2609, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30431646

RESUMO

OBJECTIVE: Pleomorphic adenoma is the most common benign salivary gland neoplasm in children. Recurrence and malignant transformation are concerns necessitating proper treatment. The goal of this research was to discuss the presentation, evaluation, and management of pediatric pleomorphic adenoma of the head and neck. METHODS: Retrospective chart review of patients under 20 years of age treated for pleomorphic adenoma of the head and neck between 1998 and 2017. Data assessed included demographics, clinical presentation, imaging, treatment, complications, recurrence, and follow-up. RESULTS: Forty-one patients with pleomorphic adenoma were identified. Major salivary gland lesions were most common (n = 32, 78.0%); 78.1% (25 of 32) arising in the parotid and 21.9% (7 of 32) in the submandibular glands. Minor salivary gland lesions were removed from the palate (5 of 9, 55.6%), buccal mucosa (2 of 9, 22.2%), parapharyngeal space (1 of 9, 11.1%), and upper lip (1 of 9, 11.1%). Preoperative imaging was reviewed in 32 patients and consisted of nine ultrasound exams, 15 computerized tomography (CT) exams, and 23 magnetic resonance imaging (MRI) exams. Multimodality imaging was performed in 14 of 32 patients. Surgical excision was performed in all patients. Postoperative complications included transient facial paresis (n = 9), Frey syndrome (n = 1), and bacterial pharyngitis (n = 1). Average length of follow-up was 25.5 months; confirmed recurrence occurred in two patients (4.9%). CONCLUSION: Evaluation of pleomorphic adenoma in children should include preoperative imaging. The goal of surgery should be complete surgical excision with negative margins. Rate of recurrence is low; however, prolonged monitoring is recommended. LEVEL OF EVIDENCE: 4. Laryngoscope, 129:2603-2609, 2019.


Assuntos
Adenoma Pleomorfo/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Neoplasias das Glândulas Salivares/diagnóstico por imagem , Tomografia por Raios X/métodos , Ultrassonografia/métodos , Adenoma Pleomorfo/cirurgia , Adolescente , Criança , Gerenciamento Clínico , Feminino , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Imagem Multimodal , Período Pré-Operatório , Estudos Retrospectivos , Neoplasias das Glândulas Salivares/cirurgia
20.
Histochem Cell Biol ; 150(6): 677-691, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30390117

RESUMO

During the last 10 + years biologically and clinically significant questions about postnatal lung development could be answered due to the application of modern cutting-edge microscopic and quantitative histological techniques. These are in particular synchrotron radiation based X-ray tomographic microscopy (SRXTM), but also 3Helium Magnetic Resonance Imaging, as well as the stereological estimation of the number of alveoli and the length of the free septal edge. First, the most important new finding may be the following: alveolarization of the lung does not cease after the maturation of the alveolar microvasculature but continues until young adulthood and, even more important, maybe reactivated lifelong if needed to rescue structural damages of the lungs. Second, the pulmonary acinus represents the functional unit of the lung. Because the borders of the acini could not be detected in classical histological sections, any investigation of the acini requires 3-dimensional (imaging) methods. Based on SRXTM it was shown that in rat lungs the number of acini stays constant, meaning that their volume increases by a factor of ~ 11 after birth. The latter is very important for acinar ventilation and particle deposition.


Assuntos
Imageamento Tridimensional , Pulmão/diagnóstico por imagem , Animais , Humanos , Tomografia por Raios X
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