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1.
Anal Bioanal Chem ; 413(3): 911-922, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33242117

RESUMO

Biofluids, such as blood plasma or serum, are currently being evaluated for cancer detection using vibrational spectroscopy. These fluids contain information of key biomolecules, such as proteins, lipids, carbohydrates and nucleic acids, that comprise spectrochemical patterns to differentiate samples. Raman is a water-free and practically non-destructive vibrational spectroscopy technique, capable of recording spectrochemical fingerprints of biofluids with minimum or no sample preparation. Herein, we compare the performance of these two common biofluids (blood plasma and serum) together with ascitic fluid, towards ovarian cancer detection using Raman microspectroscopy. Samples from thirty-eight patients were analysed (n = 18 ovarian cancer patients, n = 20 benign controls) through different spectral pre-processing and discriminant analysis techniques. Ascitic fluid provided the best class separation in both unsupervised and supervised discrimination approaches, where classification accuracies, sensitivities and specificities above 80% were obtained, in comparison to 60-73% with plasma or serum. Ascitic fluid appears to be rich in collagen information responsible for distinguishing ovarian cancer samples, where collagen-signalling bands at 1004 cm-1 (phenylalanine), 1334 cm-1 (CH3CH2 wagging vibration), 1448 cm-1 (CH2 deformation) and 1657 cm-1 (Amide I) exhibited high statistical significance for class differentiation (P < 0.001). The efficacy of vibrational spectroscopy, in particular Raman spectroscopy, combined with ascitic fluid analysis, suggests a potential diagnostic method for ovarian cancer. Raman microspectroscopy analysis of ascitic fluid allows for discrimination of patients with benign gynaecological conditions or ovarian cancer.


Assuntos
Líquido Ascítico/química , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/diagnóstico , Análise Espectral Raman/métodos , Adulto , Idoso , Algoritmos , Estudos de Casos e Controles , Análise Discriminante , Feminino , Humanos , Pessoa de Meia-Idade , Plasma , Análise de Componente Principal , Sensibilidade e Especificidade , Soro , Máquina de Vetores de Suporte
2.
Analyst ; 145(17): 5915-5924, 2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32687140

RESUMO

Raman hyperspectral imaging is a powerful technique that provides both chemical and spatial information of a sample matrix being studied. The generated data are composed of three-dimensional (3D) arrays containing the spatial information across the x- and y-axis, and the spectral information in the z-axis. Unfolding procedures are commonly employed to analyze this type of data in a multivariate fashion, where the spatial dimension is reshaped and the spectral data fits into a two-dimensional (2D) structure and, thereafter, common first-order chemometric algorithms are applied to process the data. There are only a few algorithms capable of working with the full 3D array. Herein, we propose new algorithms for 3D discriminant analysis of hyperspectral images based on a three-dimensional principal component analysis linear discriminant analysis (3D-PCA-LDA) and a three-dimensional discriminant analysis quadratic discriminant analysis (3D-PCA-QDA) approach. The analysis was performed in order to discriminate simulated and real-world data, comprising benign controls and ovarian cancer samples based on Raman hyperspectral imaging, in which 3D-PCA-LDA and 3D-PCA-QDA achieved far superior performance than classical algorithms using unfolding procedures (PCA-LDA, PCA-QDA, partial lest squares discriminant analysis [PLS-DA], and support vector machines [SVM]), where the classification accuracies improved from 66% to 83% (simulated data) and from 50% to 100% (real-world dataset) after employing the 3D techniques. 3D-PCA-LDA and 3D-PCA-QDA are new approaches for discriminant analysis of hyperspectral images multisets to provide faster and superior classification performance than traditional techniques.


Assuntos
Algoritmos , Máquina de Vetores de Suporte , Análise Discriminante , Análise de Componente Principal
3.
Stem Cells ; 34(6): 1664-78, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26866290

RESUMO

Hematopoietic stem/progenitor cells (HSPCs) reside in specialized bone marrow microenvironmental niches, with vascular elements (endothelial/mesenchymal stromal cells) and CXCR4-CXCL12 interactions playing particularly important roles for HSPC entry, retention, and maintenance. The functional effects of CXCL12 are dependent on its local concentration and rely on complex HSPC-niche interactions. Two Junctional Adhesion Molecule family proteins, Junctional Adhesion Molecule-B (JAM)-B and JAM-C, are reported to mediate HSPC-stromal cell interactions, which in turn regulate CXCL12 production by mesenchymal stromal cells (MSCs). Here, we demonstrate that another JAM family member, JAM-A, is most highly expressed on human hematopoietic stem cells with in vivo repopulating activity (p < .01 for JAM-A(high) compared to JAM-A(Int or Low) cord blood CD34(+) cells). JAM-A blockade, silencing, and overexpression show that JAM-A contributes significantly (p < .05) to the adhesion of human HSPCs to IL-1ß activated human bone marrow sinusoidal endothelium. Further studies highlight a novel association of JAM-A with CXCR4, with these molecules moving to the leading edge of the cell upon presentation with CXCL12 (p < .05 compared to no CXCL12). Therefore, we hypothesize that JAM family members differentially regulate CXCR4 function and CXCL12 secretion in the bone marrow niche. Stem Cells 2016;34:1664-1678.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Molécula A de Adesão Juncional/metabolismo , Receptores CXCR4/metabolismo , Antígeno AC133/metabolismo , Antígenos CD34/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Adesão Celular/efeitos dos fármacos , Quimiocina CXCL12/farmacologia , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Sangue Fetal/citologia , Técnicas de Silenciamento de Genes , Células HL-60 , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Células Jurkat , Ligação Proteica/efeitos dos fármacos , Nicho de Células-Tronco/efeitos dos fármacos
4.
Br J Haematol ; 169(4): 552-64, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25757087

RESUMO

Murine models of bone marrow transplantation show that pre-conditioning regimens affect the integrity of the bone marrow endothelium and that the repair of this vascular niche is an essential pre-requisite for successful haematopoietic stem and progenitor cell engraftment. Little is known about the angiogenic pathways that play a role in the repair of the human bone marrow vascular niche. We therefore established an in vitro humanized model, composed of bone marrow stromal and endothelial cells and have identified several pro-angiogenic factors, VEGFA, ANGPT1, CXCL8 and CXCL16, produced by the stromal component of this niche. We demonstrate for the first time that addition of CXCL8 or inhibition of its receptor, CXCR2, modulates blood vessel formation in our bone marrow endothelial niche model. Compared to wild type, Cxcr2(-/-) mice displayed a reduction in bone marrow cellularity and delayed platelet and leucocyte recovery following myeloablation and bone marrow transplantation. The delay in bone marrow recovery correlated with impaired bone marrow vascular repair. Taken together, our data demonstrate that CXCR2 regulates bone marrow blood vessel repair/regeneration and haematopoietic recovery, and clinically may be a therapeutic target for improving bone marrow transplantation.


Assuntos
Transplante de Medula Óssea , Medula Óssea/irrigação sanguínea , Hematopoese , Transplante de Células-Tronco Hematopoéticas , Neovascularização Fisiológica , Receptores de Interleucina-8B/metabolismo , Proteínas Angiogênicas/genética , Proteínas Angiogênicas/metabolismo , Animais , Linhagem Celular , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Knockout , Receptores de Interleucina-8B/genética , Condicionamento Pré-Transplante
5.
J Minim Invasive Gynecol ; 20(5): 672-85, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23850363

RESUMO

STUDY OBJECTIVE: To predict the 1-step complete resection rate after transrectal ultrasound-guided hysteroscopic myomectomy and to determine the usefulness of intraoperative transrectal ultrasonography (TRUS) in monitoring hysteroscopic electroresection of submucosal myomas. DESIGN: Prospective cohort study (Canadian Task Force classification II-1). SETTING: University hospital. PATIENTS: One hundred twenty women with symptomatic (abnormal uterine bleeding or reproductive disorder), single, submucosal myomas underwent hysteroscopic electroresection. Groups 1 and 2 were monitored, respectively, with or without TRUS. Anatomical inclusion criteria were myoma ≤5 cm and myometrial free margin ≥3 mm above the myoma. INTERVENTIONS: Myomas were evaluated preoperatively via sonohysterograpy and were graded according to the guidelines outlined by the European Society of Hysteroscopy (ESH), including size and myometrial free margin, and according to the STEPW (size, topography, extension, penetration, and lateral wall) classification. On the basis of sonographic findings, patients with myomas >3 cm received gonadotropin-releasing hormone therapy for 1 to 3 months. Hysteroscopic myomectomy was performed with or without TRUS guidance. At 4 to 8 weeks after the initial procedure, postoperative transvaginal ultrasonography, sonohysterography, or second-look hysteroscopy was performed. MEASUREMENTS AND MAIN RESULTS: In the TRUS group, a significantly higher percentage of 1-step complete resections was observed than in the group without TRUS (91% vs 73%) (p = .02). This was associated with a statistically significant difference in the subgroups of myomas that were deeply penetrating into the myometrium (89% vs 55%) (p < .01). One-way logistic analysis of data for all treated patients indicated the use of TRUS, as well as the ESH and STEPW classifications, as significant factors influencing the 1-step complete resection. At multivariable logistic regression analysis, use of TRUS (odds ratio [OR], 2.74; p < .001), myomas graded 0 or 1 according to ESH (OR, 3.55; p < .001), and size <3 cm (OR, 2.35; p < .05) were significantly associated with 1-step complete resection (area under the curve, 0.80; p < .001). In the TRUS group there were two significant predictors: size <3 cm (OR = 5.21; p < .05) and myometrial free margin <5 mm (OR, 0.18; p < .05). CONCLUSION: Intraoperative use of TRUS during hysteroscopic myomectomy increases the chance of complete 1-step removal of submucosal myomas that deeply penetrate the myometrium.


Assuntos
Histeroscopia/métodos , Leiomioma/cirurgia , Miomectomia Uterina/métodos , Neoplasias Uterinas/cirurgia , Adulto , Feminino , Humanos , Leiomioma/diagnóstico por imagem , Leiomioma/patologia , Resultado do Tratamento , Ultrassonografia , Hemorragia Uterina/cirurgia , Neoplasias Uterinas/diagnóstico por imagem , Neoplasias Uterinas/patologia
6.
Stem Cells Dev ; 23(22): 2730-43, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24940843

RESUMO

Proangiogenic factors, vascular endothelial growth factor (VEGF), and fibroblast growth factor-2 (FGF-2) prime endothelial cells to respond to "hematopoietic" chemokines and cytokines by inducing/upregulating expression of the respective chemokine/cytokine receptors. Coculture of human endothelial colony forming cell (ECFC)-derived cells with human stromal cells in the presence of VEGF and FGF-2 for 14 days resulted in upregulation of the "hematopoietic" chemokine CXCL12 and its CXCR4 receptor by day 3 of coculture. Chronic exposure to the CXCR4 antagonist AMD3100 in this vasculo/angiogenesis assay significantly reduced vascular tubule formation, an observation recapitulated by delayed AMD3100 addition. While AMD3100 did not affect ECFC-derived cell proliferation, it did demonstrate a dual action. First, over the later stages of the 14-day cocultures, AMD3100 delayed tubule organization into maturing vessel networks, resulting in enhanced endothelial cell retraction and loss of complexity as defined by live cell imaging. Second, at earlier stages of cocultures, we observed that AMD3100 significantly inhibited the integration of exogenous ECFC-derived cells into established, but immature, vascular networks. Comparative proteome profiler array analyses of ECFC-derived cells treated with AMD3100 identified changes in expression of potential candidate molecules involved in adhesion and/or migration. Blocking antibodies to CD31, but not CD146 or CD166, reduced the ECFC-derived cell integration into these extant vascular networks. Thus, CXCL12 plays a key role not only in endothelial cell sensing and guidance, but also in promoting the integration of ECFC-derived cells into developing vascular networks.


Assuntos
Vasos Sanguíneos/fisiologia , Quimiocina CXCL12/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/fisiologia , Sistema Hematopoético/metabolismo , Sistema Hematopoético/fisiologia , Benzilaminas , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/metabolismo , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Células Cultivadas , Técnicas de Cocultura/métodos , Ciclamos , Células Endoteliais/efeitos dos fármacos , Sistema Hematopoético/efeitos dos fármacos , Compostos Heterocíclicos/farmacologia , Humanos , Receptores CXCR4/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
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