Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
1.
Future Oncol ; 18(27): 2987-2997, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35950489

RESUMO

Myelofibrosis (MF) is a clonal myeloproliferative neoplasm, typically associated with disease-related symptoms, splenomegaly, cytopenias and bone marrow fibrosis. Patients experience a significant symptom burden and a reduced life expectancy. Patients with MF receive ruxolitinib as the current standard of care, but the depth and durability of responses and the percentage of patients achieving clinical outcome measures are limited; thus, a significant unmet medical need exists. Pelabresib is an investigational small-molecule bromodomain and extraterminal domain inhibitor currently in clinical development for MF. The aim of this article is to describe the design of the ongoing, global, phase III, double-blind, placebo-controlled MANIFEST-2 study evaluating the efficacy and safety of pelabresib and ruxolitinib versus placebo and ruxolitinib in patients with JAKi treatment-naive MF. Clinical Trial Registration: NCT04603495 (ClinicalTrials.gov).


Myelofibrosis (MF) is a rare type of blood cancer that interferes with the process of blood cell production by the bone marrow. In patients with MF, the bone marrow becomes overactive, leading to scarring and subsequently a lack of healthy blood cells being produced. The main symptoms of MF include anemia, fatigue, weakness and pain or discomfort in the abdomen. MF is associated with a shortened life expectancy. The current go-to treatment for MF is ruxolitinib. However, ruxolitinib has shown limited efficacy in improving clinical symptoms long term; so, new safe and effective treatments are needed. Pelabresib is a novel drug currently in clinical development for treating MF. The aim of this article is to describe the design of the ongoing, global phase III MANIFEST-2 study. MANIFEST-2 is evaluating the efficacy and safety of pelabresib and ruxolitinib versus placebo and ruxolitinib in patients with MF.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Mielofibrose Primária , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ensaios Clínicos Fase III como Assunto , Humanos , Inibidores de Janus Quinases/uso terapêutico , Nitrilas/uso terapêutico , Mielofibrose Primária/tratamento farmacológico , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
2.
BMJ Case Rep ; 12(11)2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31791993

RESUMO

Plasma cell neoplasms may exhibit variations in morphology and immunophenotype, which can mimic mature B-cell lymphoproliferative disorders and pose diagnostic challenges. This case illustrates a rare entity of plasma cell myeloma, where the entire plasma cell population exhibited lymphoid morphology, negativity for CD138, positivity for CD20 and cyclin D1, and positive fluorescence in situ hybridisation for t(11;14) and del(17 p), mimicking a mature B-cell lymphoproliferative disorder, in particular mantle cell lymphoma. In this case, a careful analysis of flow cytometry gating strategies and use of other ancillary tests were keys for correct diagnosis. In addition to the diagnostic implications due to its rarity, CD138-negative plasma cell myeloma may represent a unique entity, which is associated with 'stem cell'-like clonogenic properties, more aggressive clinical behaviour and resistance to chemotherapy.


Assuntos
Linfoma de Célula do Manto/diagnóstico , Mieloma Múltiplo/diagnóstico , Idoso , Antígenos CD20/sangue , Ciclina D1/sangue , Diagnóstico Diferencial , Feminino , Humanos , Sindecana-1/sangue
3.
Artigo em Inglês | MEDLINE | ID: mdl-32913992

RESUMO

PURPOSE: Dabrafenib and trametinib are approved for the management of advanced non-small-cell lung cancers (NSCLCs) that harbor BRAF V600E mutations. Small series and pan-cancer analyses have identified non-V600 alterations as therapeutic targets. We sought to examine a large genomic data set to comprehensively characterize non-V600 BRAF alterations in lung cancer. PATIENTS AND METHODS: A total of 23,396 patients with lung cancer provided data to assay with comprehensive genomic profiling. Data were reviewed for predicted pathogenic BRAF base substitutions, short insertions and deletions, copy number changes, and rearrangements. RESULTS: Adenocarcinomas represented 65% of the occurrences; NSCLC not otherwise specified (NOS), 15%; squamous cell carcinoma, 12%; and small-cell lung carcinoma, 5%. BRAF was altered in 4.5% (1,048 of 23,396) of all tumors; 37.4% (n = 397) were BRAF V600E, 38% were BRAF non-V600E activating mutations, and 18% were BRAF inactivating. Rearrangements were observed at a frequency of 4.3% and consisted of N-terminal deletions (NTDs; 0.75%), kinase domain duplications (KDDs; 0.75%), and BRAF fusions (2.8%). The fusions involved three recurrent fusion partners: ARMC10, DOCK4, and TRIM24. BRAF V600E was associated with co-occurrence of SETD2 alterations, but other BRAF alterations were not and were instead associated with CDKN2A, TP53, and STK11 alterations (P < .05). Potential mechanisms of acquired resistance to BRAF V600E inhibition are demonstrated. CONCLUSION: This series characterized the frequent occurrence (4.4%) of BRAF alterations in lung cancers. Recurrent BRAF alterations in NSCLC adenocarcinoma are comparable to the frequency of other NSCLC oncogenic drivers, such as ALK, and exceed that of ROS1 or RET. This work supports a broad profiling approach in lung cancers and suggests that non-V600E BRAF alterations represent a subgroup of lung cancers in which targeted therapy should be considered.

4.
J Clin Oncol ; 35(9): 929-933, 2017 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-28297627

RESUMO

The emergence of precision medicine has been predicated on significant recent advances in diagnostic technology, particularly the advent of next-generation sequencing (NGS). Although the chemical technology underlying NGS is complex, and the computational biology expertise required to build systems to facilely interpret the results is highly specialized, the variables involved in designing and deploying a genomic testing program for cancer can be readily understood and applied by understanding several basic considerations. In this review, we present key strategic decisions required to optimize a genomic testing program and summarize the technical aspects of different technologies that render those methods more or less suitable for different types of programs.


Assuntos
Genômica/métodos , Neoplasias/diagnóstico , Neoplasias/genética , Medicina de Precisão/métodos , Testes Genéticos/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos
5.
Med Image Anal ; 38: 104-116, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28327449

RESUMO

This paper proposes a texture analysis technique that can effectively classify different types of human breast tissue imaged by Optical Coherence Microscopy (OCM). OCM is an emerging imaging modality for rapid tissue screening and has the potential to provide high resolution microscopic images that approach those of histology. OCM images, acquired without tissue staining, however, pose unique challenges to image analysis and pattern classification. We examined multiple types of texture features and found Local Binary Pattern (LBP) features to perform better in classifying tissues imaged by OCM. In order to improve classification accuracy, we propose novel variants of LBP features, namely average LBP (ALBP) and block based LBP (BLBP). Compared with the classic LBP feature, ALBP and BLBP features provide an enhanced encoding of the texture structure in a local neighborhood by looking at intensity differences among neighboring pixels and among certain blocks of pixels in the neighborhood. Fourty-six freshly excised human breast tissue samples, including 27 benign (e.g. fibroadenoma, fibrocystic disease and usual ductal hyperplasia) and 19 breast carcinoma (e.g. invasive ductal carcinoma, ductal carcinoma in situ and lobular carcinoma in situ) were imaged with large field OCM with an imaging area of 10 × 10 mm2 (10, 000 × 10, 000 pixels) for each sample. Corresponding H&E histology was obtained for each sample and used to provide ground truth diagnosis. 4310 small OCM image blocks (500 × 500 pixels) each paired with corresponding H&E histology was extracted from large-field OCM images and labeled with one of the five different classes: adipose tissue (n = 347), fibrous stroma (n = 2,065), breast lobules (n = 199), carcinomas (pooled from all sub-types, n = 1,127), and background (regions outside of the specimens, n = 572). Our experiments show that by integrating a selected set of LBP and the two new variant (ALBP and BLBP) features at multiple scales, the classification accuracy increased from 81.7% (using LBP features alone) to 93.8% using a neural network classifier. The integrated feature was also used to classify large-field OCM images for tumor detection. A receiver operating characteristic (ROC) curve was obtained with an area under the curve value of 0.959. A sensitivity level of 100% and specificity level of 85.2% was achieved to differentiate benign from malignant samples. Several other experiments also demonstrate the complementary nature of LBP and the two variants (ALBP and BLBP features) and the significance of integrating these texture features for classification. Using features from multiple scales and performing feature selection are also effective mechanisms to improve accuracy while maintaining computational efficiency.


Assuntos
Algoritmos , Neoplasias da Mama/diagnóstico por imagem , Mama/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Microscopia Confocal/métodos , Reconhecimento Automatizado de Padrão/métodos , Tomografia de Coerência Óptica/métodos , Feminino , Humanos , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Clin Lung Cancer ; 17(6): 483-492, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27381270

RESUMO

Expert consensus guidelines have defined minimum requirements for routine testing and identification of classical epidermal growth factor (EGFR) mutations (ie, exon 19 deletions and exon 21 L858R substitution) and anaplastic lymphoma kinase (ALK) rearrangements in advanced non-small-cell lung cancers of adenocarcinoma histology, with the intent of permitting use of these predictive biomarkers to select patients who will derive maximal benefit from approved oral tyrosine kinase inhibitors (TKIs) directed against EGFR and ALK, respectively. However, the practice of precision medicine is incumbent upon optimal tumor sampling, accurate tumor testing, and informed application of results to patient care. We report on a brief review of EGFR testing methodologies (Sanger sequencing, allele-specific polymerase chain reaction, and targeted next-generation sequencing) to identify classical and other (ie, exon 18 G719X, exon 19 insertions, exon 20 insertions, exon 21 L861Q) EGFR mutations; practical considerations (type of tissue/biopsies with different success rates of DNA isolation, and timeliness of result-reporting to facilitate therapeutic decision-making); role of rebiopsy (to identify mechanisms of acquired resistance to first- and second-generation EGFR TKIs, most importantly EGFR-T790M); and clinical vignettes highlighting the nuances of testing in day-to-day practice.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Receptores ErbB/genética , Neoplasias Pulmonares/tratamento farmacológico , Mutação/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Humanos , Neoplasias Pulmonares/genética , Terapia de Alvo Molecular , Medicina de Precisão , Valor Preditivo dos Testes
7.
Biomed Opt Express ; 6(11): 4317-25, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26600997

RESUMO

Two photon fluorescent lifetime imaging is a modality that enables depth-sectioned, molecularly-specific imaging of cells and tissue using intrinsic contrast. However, clinical applications have not been well explored due to low imaging speed and limited field of view, which make evaluating large pathology samples extremely challenging. To address these limitations, we have developed direct temporal sampling two photon fluorescent lifetime imaging (DTS-FLIM), a method which enables a several order of magnitude increase in imaging speed by capturing an entire lifetime decay in a single fluorescent excitation. We use this greatly increased speed to perform a preliminary study using gigapixel-scale imaging of human breast pathology surgical specimens.

9.
Pediatr Nephrol ; 30(7): 1197-202, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25911531

RESUMO

BACKGROUND: Immunodysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) disorder is an autoimmune disease caused by loss-of-function mutations in the gene encoding the forkhead box P3 (FOXP3) transcription factor. These mutations affect the normal function of circulating regulatory T cells. IPEX is characterized by profound immune dysregulation leading to dermatitis, enteropathy, multiple endocrinopathies and failure to thrive. Different forms of renal injury have also been noted in these patients but these have been described to a very limited extent. CASE-DIAGNOSIS: Three patients with IPEX with characteristic renal findings and mutations in FOXP3, including one novel mutation, are described. Case presentations are followed by a review of the renal manifestations noted in IPEX and the range of therapeutic options for this disorder. CONCLUSIONS: We recommend that IPEX be considered in the differential diagnosis of young children who present with signs of immune dysregulation with a concomitant renal biopsy demonstrating immune complex deposition in a membranous-like pattern and/or interstitial nephritis.


Assuntos
Doenças Genéticas Ligadas ao Cromossomo X/patologia , Rim/patologia , Adolescente , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Biópsia , Criança , Pré-Escolar , Evolução Fatal , Fatores de Transcrição Forkhead/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/imunologia , Testes Genéticos , Humanos , Lactente , Masculino , Mutação/genética , Pele/patologia , Transplante de Células-Tronco , Síndrome , Linfócitos T Reguladores/imunologia
10.
Pediatr Dermatol ; 32(3): e98-101, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25739384

RESUMO

Hypertrophic lichen planus (HLP) is a T-cell-mediated process typically presenting with hypertrophic or verrucous plaques on the lower limbs. We report the case of a 24-year-old woman with a history of HLP since age 3 years presenting with rapid malignant transformation of one lesion into a large squamous cell carcinoma (SCC). Subsequent examination revealed progressive, widespread metastatic involvement, and the patient ultimately died from her disease. SCC associated with HLP is rare, with a review of the literature revealing fewer than 50 cases. This case highlights the need to be aware of suspicious changes in HLP and to educate patients as to when to be reevaluated.


Assuntos
Carcinoma de Células Escamosas/patologia , Transformação Celular Neoplásica/patologia , Líquen Plano/patologia , Neoplasias Cutâneas/patologia , Diagnóstico Diferencial , Evolução Fatal , Feminino , Humanos , Adulto Jovem
11.
Proc Natl Acad Sci U S A ; 111(43): 15304-9, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25313045

RESUMO

Rapid intraoperative assessment of breast excision specimens is clinically important because up to 40% of patients undergoing breast-conserving cancer surgery require reexcision for positive or close margins. We demonstrate nonlinear microscopy (NLM) for the assessment of benign and malignant breast pathologies in fresh surgical specimens. A total of 179 specimens from 50 patients was imaged with NLM using rapid extrinsic nuclear staining with acridine orange and intrinsic second harmonic contrast generation from collagen. Imaging was performed on fresh, intact specimens without the need for fixation, embedding, and sectioning required for conventional histopathology. A visualization method to aid pathological interpretation is presented that maps NLM contrast from two-photon fluorescence and second harmonic signals to features closely resembling histopathology using hematoxylin and eosin staining. Mosaicking is used to overcome trade-offs between resolution and field of view, enabling imaging of subcellular features over square-centimeter specimens. After NLM examination, specimens were processed for standard paraffin-embedded histology using a protocol that coregistered histological sections to NLM images for paired assessment. Blinded NLM reading by three pathologists achieved 95.4% sensitivity and 93.3% specificity, compared with paraffin-embedded histology, for identifying invasive cancer and ductal carcinoma in situ versus benign breast tissue. Interobserver agreement was κ = 0.88 for NLM and κ = 0.89 for histology. These results show that NLM achieves high diagnostic accuracy, can be rapidly performed on unfixed specimens, and is a promising method for intraoperative margin assessment.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Microscopia/métodos , Dinâmica não Linear , Neoplasias da Mama/diagnóstico , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Feminino , Humanos , Invasividade Neoplásica , Sensibilidade e Especificidade
12.
Mol Med ; 20: 456-65, 2014 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25032953

RESUMO

Atherosclerosis is an inflammatory disease and the main cause of cardiovascular disease. Inflammation promotes plaque instability and clinical disease, such as myocardial infarction, stroke and peripheral vascular disease. Subclinical atherosclerosis begins with thickening of the arterial intimal layer, and increased intima-media thickness (IMT) in the carotid artery is a widely used measurement of subclinical atherosclerosis. Activation of CD137 (tumor necrosis factor receptor super family 9) promotes inflammation and disease development in murine atherosclerosis. CD137 is expressed in human atherosclerosis, but its role is largely unknown. This study uses a genetic approach to investigate CD137 in human atherosclerotic disease. In publicly available data on genotype and gene expression from the HapMap project, the minor T allele of rs2453021, a single nucleotide polymorphism in CD137, was significantly associated with CD137 gene expression. In the PROCARDIS and Wellcome Trust Case Control Consortium (WTCCC) cohorts of 13,029 cases and controls, no significant association was detected between the minor T allele of rs2453021 and risk for coronary artery disease or myocardial infarction. However, in the IMPROVE multicenter study of 3,418 individuals, the minor T allele of rs2453021 was associated with increased IMT of the common carotid artery (CCA), as measured by ultrasonography, with presence of plaque in CCA and with increased incidence of adverse noncardiac vascular events. Taken together, this study shows that the minor T allele of rs2453021 is associated with increased IMT in the CCA and increased risk of incident noncardiac vascular events, thus providing the first human genetic evidence for involvement of CD137 in atherosclerosis.


Assuntos
Aterosclerose/genética , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética , Idoso , Alelos , Aterosclerose/diagnóstico por imagem , Aterosclerose/patologia , Artéria Carótida Primitiva/diagnóstico por imagem , Artéria Carótida Primitiva/patologia , Espessura Intima-Media Carotídea , Linhagem Celular , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , RNA Mensageiro/metabolismo
13.
Arterioscler Thromb Vasc Biol ; 34(7): 1374-81, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24812325

RESUMO

OBJECTIVE: Obesity associates with increased numbers of inflammatory cells in adipose tissue (AT), including T cells, but the mechanism of T-cell recruitment remains unknown. This study tested the hypothesis that the chemokine (C-X-C motif) receptor 3 (CXCR3) participates in T-cell accumulation in AT of obese mice and thus in the regulation of local inflammation and systemic metabolism. APPROACH AND RESULTS: Obese wild-type mice exhibited higher mRNA expression of CXCR3 in periepididymal AT-derived stromal vascular cells compared with lean mice. We evaluated the function of CXCR3 in AT inflammation in vivo using CXCR3-deficient and wild-type control mice that consumed a high-fat diet. Periepididymal AT from obese CXCR3-deficient mice contained fewer T cells than obese controls after 8 and 16 weeks on high-fat diet, as assessed by flow cytometry. Obese CXCR3-deficient mice had greater glucose tolerance than obese controls after 8 weeks, but not after 16 weeks. CXCR3-deficient mice fed high-fat diet had reduced mRNA expression of proinflammatory mediators, such as monocyte chemoattractant protein-1 and regulated on activation, normal T cell expressed and secreted, and anti-inflammatory genes, such as Foxp3, IL-10, and arginase-1 in periepididymal AT, compared with obese controls. CONCLUSIONS: These results demonstrate that CXCR3 contributes to T-cell accumulation in periepididymal AT of obese mice. Our results also suggest that CXCR3 regulates the accumulation of distinct subsets of T cells and that the ratio between these functional subsets across time likely modulates local inflammation and systemic metabolism.


Assuntos
Tecido Adiposo/imunologia , Quimiotaxia de Leucócito , Obesidade/imunologia , Paniculite/imunologia , Receptores CXCR3/metabolismo , Subpopulações de Linfócitos T/imunologia , Tecido Adiposo/metabolismo , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/genética , Obesidade/metabolismo , Paniculite/genética , Paniculite/metabolismo , Receptores CXCR3/deficiência , Receptores CXCR3/genética , Transdução de Sinais , Subpopulações de Linfócitos T/metabolismo , Fatores de Tempo
14.
Lancet Oncol ; 15(5): 489-538, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24731404

RESUMO

Cancer is one of the major non-communicable diseases posing a threat to world health. Unfortunately, improvements in socioeconomic conditions are usually associated with increased cancer incidence. In this Commission, we focus on China, India, and Russia, which share rapidly rising cancer incidence and have cancer mortality rates that are nearly twice as high as in the UK or the USA, vast geographies, growing economies, ageing populations, increasingly westernised lifestyles, relatively disenfranchised subpopulations, serious contamination of the environment, and uncontrolled cancer-causing communicable infections. We describe the overall state of health and cancer control in each country and additional specific issues for consideration: for China, access to care, contamination of the environment, and cancer fatalism and traditional medicine; for India, affordability of care, provision of adequate health personnel, and sociocultural barriers to cancer control; and for Russia, monitoring of the burden of cancer, societal attitudes towards cancer prevention, effects of inequitable treatment and access to medicine, and a need for improved international engagement.


Assuntos
Neoplasias/terapia , Idoso , Idoso de 80 Anos ou mais , Alcoolismo/epidemiologia , Neoplasias da Mama/diagnóstico , China , Neoplasias Colorretais/diagnóstico , Características Culturais , Detecção Precoce de Câncer/tendências , Desenvolvimento Econômico/tendências , Poluição Ambiental/efeitos adversos , Etnicidade , Feminino , Serviços de Saúde/economia , Acessibilidade aos Serviços de Saúde/tendências , Mão de Obra em Saúde/tendências , Disparidades em Assistência à Saúde/tendências , Humanos , Índia , Masculino , Medicina Tradicional Chinesa , Pessoa de Meia-Idade , Neoplasias/prevenção & controle , Serviços de Saúde Rural/tendências , Federação Russa/epidemiologia , Sexismo , Fumar , Estigma Social , Serviços Urbanos de Saúde/tendências
15.
Biomed Opt Express ; 4(8): 1236-54, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24009989

RESUMO

We demonstrate a compact, ultrahigh speed spectral-domain optical coherence microscopy (SD-OCM) system for multiscale imaging of specimens at 840 nm. Using a high speed 512-pixel line scan camera, an imaging speed of 210,000 A-scans per second was demonstrated. Interchangeable water immersion objectives with magnifications of 10×, 20×, and 40× provided co-registered en face cellular-resolution imaging over several size scales. Volumetric OCM data sets and en face OCM images were demonstrated on both normal and pathological human colon and kidney specimens ex vivo with an axial resolution of ~4.2 µm, and transverse resolutions of ~2.9 µm (10×), ~1.7 µm (20×), and ~1.1 µm (40×) in tissue. In addition, en face OCM images acquired with high numerical aperture over an extended field-of-view (FOV) were demonstrated using image mosaicking. Comparison between en face OCM images among different transverse and axial resolutions was demonstrated, which promises to help the design and evaluation of imaging performance of Fourier domain OCM systems at different resolution regimes.

16.
Opt Express ; 21(15): 18021-33, 2013 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-23938673

RESUMO

We demonstrate high speed, swept source optical coherence microscopy (OCM) using a MEMS tunable vertical cavity surface-emitting laser (VCSEL) light source. The light source had a sweep rate of 280 kHz, providing a bidirectional axial scan rate of 560 kHz. The sweep bandwidth was 117 nm centered at 1310 nm, corresponding to an axial resolution of 13.1 µm in air, corresponding to 8.1 µm (9.6 µm spectrally shaped) in tissue. Dispersion mismatch from different objectives was compensated numerically, enabling magnification and field of view to be easily changed. OCM images were acquired with transverse resolutions between 0.86 µm - 3.42 µm using interchangeable 40X, 20X and 10X objectives with ~600 µm x 600 µm, ~1 mm x 1 mm and ~2 mm x 2 mm field-of-view (FOV), respectively. Parasitic variations in path length with beam scanning were corrected numerically. These features enable swept source OCM to be integrated with a wide range of existing scanning microscopes. Large FOV mosaics were generated by serially acquiring adjacent overlapping microscopic fields and combining them in post-processing. Fresh human colon, thyroid and kidney specimens were imaged ex vivo and compared to matching histology sections, demonstrating the ability of OCM to image tissue specimens.


Assuntos
Aumento da Imagem/instrumentação , Lasers , Iluminação/instrumentação , Microscopia/instrumentação , Tomografia de Coerência Óptica/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos
18.
Am J Cancer Res ; 2(2): 153-67, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22432056

RESUMO

Testicular germ cell tumors (TGCT) are the most common malignancy in young men. While most TGCT are potentially curable, approximately 5% of patients with TGCT may develop chemoresistance and die from the disease. This review article summarizes current knowledge in genetics underlying the development, progression and chemoresistance of TGCT. Most post-pubertal TGCT originate from intratubular germ cell neoplasia unclassified (IGCNU), which are transformed fetal gonocytes. Development of IGCNU may involve aberrantly activated KITLG/KIT pathway and overexpression of embryonic transcription factors such as NANOG and POU5F1, which leads to suppression of apoptosis, increased proliferation, and accumulation of mutations in gonocytes. Invasive TGCT consistently show gain of chromosome 12p, typically isochromosome 12p. Single gene mutations are uncommon in TGCT. KIT, TP53, KRAS/NRAS, and BRAF are genes most commonly mutated in TGCT and implicated in their pathogenesis. Different histologic subtypes of TGCT possess different gene expression profiles that reflect different directions of differentiation. Their distinct gene expression profiles are likely caused by epigenetic regulation, in particular DNA methylation, but not by gene copy number alterations. Resistance of TGCT to chemotherapy has been linked to karyotypic aberrations, single-gene mutations, and epigenetic regulation of gene expression in small-scale studies. The study of TGCT genetics could ultimately translate into development of new molecular diagnostic and therapeutic modalities for these tumors and improve the care of patients with these malignancies.

19.
J Urol ; 187(2): 691-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22177199

RESUMO

PURPOSE: We evaluated the feasibility of using optical coherence tomography and optical coherence microscopy technology to assess human kidney morphology. MATERIALS AND METHODS: A total of 35 renal specimens from 19 patients, consisting of 12 normal tissues and 23 tumors (16 clear cell renal cell carcinomas, 5 papillary renal cell carcinomas and 2 oncocytomas) were imaged ex vivo after surgical resection. Optical coherence tomography and optical coherence microscopy images were compared to corresponding hematoxylin and eosin histology to identify characteristic features of normal and pathological renal tissues. Three pathologists blinded to histology evaluated the sensitivity and specificity of optical coherence microscopy images to differentiate normal from neoplastic renal tissues. RESULTS: Optical coherence tomography and optical coherence microscopy images of normal kidney revealed architectural features, including glomeruli, convoluted tubules, collecting tubules and loops of Henle. Each method of imaging renal tumors clearly demonstrated morphological changes and decreased imaging depth. Optical coherence tomography and microscopy features matched well with the corresponding histology. Three observers achieved 88%, 100% and 100% sensitivity, and 100%, 88% and 100% specificity, respectively, when evaluating normal vs neoplastic specimens using optical coherence microscopy images with substantial interobserver agreement (κ = 0.82, p <0.01). CONCLUSIONS: Integrated optical coherence tomography and optical coherence microscopy imaging provides coregistered, multiscale images of renal pathology in real time without exogenous contrast medium or histological processing. High sensitivity and specificity were achieved using optical coherence microscopy to differentiate normal from neoplastic renal tissues, suggesting possible applications for guiding renal mass biopsy or evaluating surgical margins.


Assuntos
Adenoma Oxífilo/patologia , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Tomografia de Coerência Óptica/métodos , Adulto , Idoso , Humanos , Pessoa de Meia-Idade
20.
J Am Coll Cardiol ; 58(6): 603-14, 2011 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-21798423

RESUMO

OBJECTIVES: This study investigated the regulation of glucose uptake in cells that participate in atherogenesis by stimuli relevant to this process, to gain mechanistic insight into the origin of the (18)fluorine-labeled 2-deoxy-D-glucose (FdG) uptake signals observed clinically. BACKGROUND: Patient studies suggest that positron emission tomography (PET) using FdG can detect "active" atherosclerotic plaques, yet the mechanism giving rise to FdG signals remains unknown. METHODS: We exposed cells to conditions thought to operate in atheroma and determined rates of glucose uptake. RESULTS: Hypoxia, but not pro-inflammatory cytokines, potently stimulated glucose uptake in human macrophages and foam cells. Statins attenuated this process in vitro, suggesting that these agents have a direct effect on human macrophages. Immunohistochemical study of human plaques revealed abundant expression of proteins regulating glucose utilization, predominantly in macrophage-rich regions of the plaques-regions previously proved hypoxic. Smooth-muscle cells and endothelial cells markedly increased rates of glucose uptake when exposed to pro-inflammatory cytokines. CONCLUSIONS: Glucose uptake and, probably, FdG uptake signals in atheroma may reflect hypoxia-stimulated macrophages rather than mere inflammatory burden. Cytokine-activated smooth-muscle cells also may contribute to the FdG signal.


Assuntos
Aterosclerose/diagnóstico por imagem , Aterosclerose/terapia , Glucose/farmacocinética , Hipóxia , Inflamação , Macrófagos/efeitos dos fármacos , Aorta/patologia , Aterosclerose/patologia , Citocinas/metabolismo , Células Endoteliais/citologia , Fluordesoxiglucose F18/farmacologia , Células Espumosas/metabolismo , Glucose/metabolismo , Humanos , Hidrólise , Macrófagos/metabolismo , Monócitos/citologia , Miócitos de Músculo Liso/metabolismo , Tomografia por Emissão de Pósitrons/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...