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1.
Cytometry A ; 103(11): 857-867, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37565838

RESUMEN

Acute leukemia is usually diagnosed when a test of peripheral blood shows at least 20% of abnormal immature cells (blasts), a figure even lower in case of recurrent cytogenetic abnormalities. Blast identification is crucial for white blood cell (WBC) counting, which depends on both identifying the cell type and characterizing the cellular morphology, processes susceptible of inter- and intraobserver variability. The present work introduces an image combined-descriptor to detect blasts and determine their probable lineage. This strategy uses an intra-nucleus mosaic pattern (InMop) descriptor that captures subtle nuclei differences within WBCs, and Haralick's statistics which quantify the local structure of both nucleus and cytoplasm. The InMop captures WBC inner-nucleus structure by applying a multiscale Shearlet decomposition over a repetitive pattern (mosaic) of automatically-segmented nuclei. As a complement, Haralick's statistics characterize the local structure of the whole cell from an intensity co-occurrence matrix representation. Both InMoP and Haralick-based descriptors are calculated using the b-channel from Lab color-space. The combined-descriptor is assessed by differentiating blasts from nonleukemic cells with support vector machine (SVM) classifiers and different transformation kernels, in two public and independent databases. The first database-D1 (n = 260) is composed of healthy and acute lymphoid leukemia (ALL) single cell images, and second database-D2 contains acute myeloid leukemia (AML) blasts (n = 3294) and nonblast (n = 15,071) cell images. In a first experiment, blasts versus nonblast differentiation is performed by training with a subset of D2 (n = 6588) and testing in D1 (n = 260), obtaining a training AUC of 0.991 ± 0.002 and AUC = 0.782 for the independent validation. A second experiment automatically differentiates AML blasts (260 images from D2) from ALL blasts (260 images from D1), with an AUC of 0.93. In a third experiment, state-of-the-art strategies, VGG16 and RESNEXT convolutional neural networks (CNN), separate blast from nonblast cells in both databases. The VGG16 showed an AUC of 0.673 and the RESNEXT of 0.75. Reported metrics for all the experiments are area under the ROC curve (AUC), accuracy and F1-score.


Asunto(s)
Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucocitos , Recuento de Leucocitos , Citoplasma
2.
BMC Cancer ; 16: 591, 2016 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-27484900

RESUMEN

BACKGROUND: Experimental evidence and clinical studies in breast cancer suggest that some anti-tumor therapy regimens generate stimulation of the immune system that accounts for tumor clinical responses, however, demonstration of the immunostimulatory power of these therapies on cancer patients continues to be a formidable challenge. Here we present experimental evidence from a breast cancer patient with complete clinical response after 7 years, associated with responsiveness of tumor specific T cells. METHODS: T cells were obtained before and after anti-tumor therapy from peripheral blood of a 63-years old woman diagnosed with ductal breast cancer (HER2/neu+++, ER-, PR-, HLA-A*02:01) treated with surgery, followed by paclitaxel, trastuzumab (suspended due to cardiac toxicity), and radiotherapy. We obtained a leukapheresis before surgery and after 8 months of treatment. Using in vitro cell cultures stimulated with autologous monocyte-derived dendritic cells (DCs) that produce high levels of IL-12, we characterize by flow cytometry the phenotype of tumor associated antigens (TAAs) HER2/neu and NY-ESO 1 specific T cells. The ex vivo analysis of the TCR-Vß repertoire of TAA specific T cells in blood and Tumor Infiltrating Lymphocytes (TILs) were performed in order to correlate both repertoires prior and after therapy. RESULTS: We evidence a functional recovery of T cell responsiveness to polyclonal stimuli and expansion of TAAs specific CD8+ T cells using peptide pulsed DCs, with an increase of CTLA-4 and memory effector phenotype after anti-tumor therapy. The ex vivo analysis of the TCR-Vß repertoire of TAA specific T cells in blood and TILs showed that whereas the TCR-Vß04-02 clonotype is highly expressed in TILs the HER2/neu specific T cells are expressed mainly in blood after therapy, suggesting that this particular TCR was selectively enriched in blood after anti-tumor therapy. CONCLUSIONS: Our results show the benefits of anti-tumor therapy in a breast cancer patient with clinical complete response in two ways, by restoring the responsiveness of T cells by increasing the frequency and activation in peripheral blood of tumor specific T cells present in the tumor before therapy.


Asunto(s)
Neoplasias de la Mama/inmunología , Carcinoma Ductal de Mama/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos T/inmunología , Antígenos de Neoplasias/inmunología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/terapia , Carcinoma Ductal de Mama/terapia , Quimioradioterapia , Femenino , Citometría de Flujo , Humanos , Activación de Linfocitos/inmunología , Persona de Mediana Edad , Paclitaxel/uso terapéutico , Trastuzumab/uso terapéutico
3.
Nat Med ; 8(8): 841-9, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12091880

RESUMEN

The mechanism by which angiogenic factors recruit bone marrow (BM)-derived quiescent endothelial and hematopoietic stem cells (HSCs) is not known. Here, we report that functional vascular endothelial growth factor receptor-1 (VEGFR1) is expressed on human CD34(+) and mouse Lin(-)Sca-1(+)c-Kit(+) BM-repopulating stem cells, conveying signals for recruitment of HSCs and reconstitution of hematopoiesis. Inhibition of VEGFR1, but not VEGFR2, blocked HSC cell cycling, differentiation and hematopoietic recovery after BM suppression, resulting in the demise of the treated mice. Placental growth factor (PlGF), which signals through VEGFR1, restored early and late phases of hematopoiesis following BM suppression. PlGF enhanced early phases of BM recovery directly through rapid chemotaxis of VEGFR1(+) BM-repopulating and progenitor cells. The late phase of hematopoietic recovery was driven by PlGF-induced upregulation of matrix metalloproteinase-9, mediating the release of soluble Kit ligand. Thus, PlGF promotes recruitment of VEGFR1(+) HSCs from a quiescent to a proliferative BM microenvironment, favoring differentiation, mobilization and reconstitution of hematopoiesis.


Asunto(s)
Hematopoyesis/fisiología , Células Madre Hematopoyéticas/metabolismo , Proteínas Gestacionales/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Animales , Antimetabolitos Antineoplásicos/farmacología , Separación Celular , Trasplante de Células , Quimiotaxis , Femenino , Fluorouracilo/farmacología , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Masculino , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones , Ratones Endogámicos , Factor de Crecimiento Placentario , Receptores de Factores de Crecimiento/metabolismo , Receptores de Factores de Crecimiento Endotelial Vascular , Quimera por Trasplante , Trasplante Heterólogo , Receptor 1 de Factores de Crecimiento Endotelial Vascular
4.
Nat Med ; 10(1): 64-71, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14702636

RESUMEN

The molecular pathways involved in the differentiation of hematopoietic progenitors are unknown. Here we report that chemokine-mediated interactions of megakaryocyte progenitors with sinusoidal bone marrow endothelial cells (BMECs) promote thrombopoietin (TPO)-independent platelet production. Megakaryocyte-active cytokines, including interleukin-6 (IL-6) and IL-11, did not induce platelet production in thrombocytopenic, TPO-deficient (Thpo(-/-)) or TPO receptor-deficient (Mpl(-/-)) mice. In contrast, megakaryocyte-active chemokines, including stromal-derived factor-1 (SDF-1) and fibroblast growth factor-4 (FGF-4), restored thrombopoiesis in Thpo(-/-) and Mpl(-/-) mice. FGF-4 and SDF-1 enhanced vascular cell adhesion molecule-1 (VCAM-1)- and very late antigen-4 (VLA-4)-mediated localization of CXCR4(+) megakaryocyte progenitors to the vascular niche, promoting survival, maturation and platelet release. Disruption of the vascular niche or interference with megakaryocyte motility inhibited thrombopoiesis under physiological conditions and after myelosuppression. SDF-1 and FGF-4 diminished thrombocytopenia after myelosuppression. These data suggest that TPO supports progenitor cell expansion, whereas chemokine-mediated interaction of progenitors with the bone marrow vascular niche allows the progenitors to relocate to a microenvironment that is permissive and instructive for megakaryocyte maturation and thrombopoiesis. Progenitor-active chemokines offer a new strategy to restore hematopoiesis in a clinical setting.


Asunto(s)
Médula Ósea/irrigación sanguínea , Quimiocinas/fisiología , Células Madre Hematopoyéticas/citología , Trombopoyesis/fisiología , Animales , Antígenos CD , Cadherinas/fisiología , Adhesión Celular/fisiología , Movimiento Celular/fisiología , Megacariocitos/citología , Ratones , Proteínas Oncogénicas/genética , Proteínas Oncogénicas/fisiología , Receptores CXCR4/fisiología , Receptores de Citocinas/genética , Receptores de Citocinas/fisiología , Receptores de Trombopoyetina , Trombopoyetina/genética , Trombopoyetina/fisiología
5.
Circulation ; 112(23): 3644-53, 2005 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-16330706

RESUMEN

BACKGROUND: Accumulation of macrophages and smooth muscle cells in the vascular wall is critical for the development of atherosclerotic lesions. Although much is known about the factors that regulate macrophage recruitment to the vascular wall, the ability of growth factors to regulate smooth muscle cell recruitment in lesion development in vivo is unclear. Our previous studies demonstrated that neurotrophins and their receptors, the Trk receptor tyrosine kinases, are potent chemotactic factors for smooth muscle cells, and the expression of brain-derived neurotrophic factor (BDNF) and its cognate receptor, TrkB, is upregulated in human atherosclerotic lesions. METHODS AND RESULTS: TrkB(+/-) mice on a 129/B6 background were backcrossed to apolipoprotein E (ApoE)-null (ApoE(-/-)) mice on the C57Bl/6 background for 6 to 8 generations. Immunohistochemical analysis demonstrated BDNF immunoreactivity in areas of macrophage and smooth muscle cell infiltration, whereas TrkB immunoreactivity was predominant in areas of neointimal smooth muscle cells. Moreover, haplodeficient expression of TrkB in ApoE(-/-) mice was associated with a 30% to 40% reduction in lesion size compared with ApoE(-/-) mice with normal expression of TrkB and a 45% decrease in smooth muscle cell accumulation in the lesions. Finally, reconstitution with bone marrow from ApoE(-/-) mice with normal TrkB expression did not restore lesion development in TrKB(+/-)/ApoE(-/-) mice. CONCLUSIONS: These results suggest that TrkB expression on smooth muscle cells contributes to lesion development in the cholesterol-fed ApoE-null mutant mouse. These data demonstrate, for the first time, a role for the neurotrophin TrkB receptor in atherosclerotic lesion development.


Asunto(s)
Arteriosclerosis/etiología , Receptor trkB/genética , Receptor trkB/fisiología , Animales , Apolipoproteínas E/deficiencia , Arteriosclerosis/patología , Factor Neurotrófico Derivado del Encéfalo/análisis , Quimiotaxis , Colesterol/administración & dosificación , Regulación de la Expresión Génica/fisiología , Macrófagos/química , Macrófagos/fisiología , Ratones , Ratones Noqueados , Miocitos del Músculo Liso/química , Miocitos del Músculo Liso/fisiología
6.
Ann N Y Acad Sci ; 996: 49-60, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12799282

RESUMEN

The mechanism by which angiogenic factors recruit bone marrow (BM)-derived quiescent endothelial and hematopoietic stem cells (HSCs) is not known. Here, we report that functional vascular endothelial growth factor receptor-1 (VEGFR1, Flt-1) is expressed on a subpopulation of human CD34(+) and mouse Lin-Sca-1(+)c-Kit(+) BM-repopulating stem cells, conveying signals for recruitment of HSCs and reconstitution of hematopoiesis. Inhibition of VEGFR1 signaling, but not VEGFR2 (Flk-1, KDR), blocked HSC cell cycling, differentiation and hematopoietic recovery after BM suppression, resulting in the demise of the treated mice. Plasma elevation of placental growth factor (PlGF), which signals through VEGFR1, but not VEGFR2, restored hematopoiesis during the early and late phases following BM suppression. The mechanism whereby PlGF enhanced early phases of BM recovery was mediated directly through rapid chemotaxis of readily available VEGFR1(+) BM-repopulating and progenitor cells. The late phase of hematopoietic recovery was driven by PlGF-induced upregulation of matrix metalloproteinase-9 (MMP-9) in the BM, mediating the release of soluble Kit-ligand (sKitL). sKitL increased proliferation and motility of HSCs and progenitor cells, thereby augmenting hematopoietic recovery. PlGF promotes recruitment of VEGFR1(+) HSCs from a quiescent to a proliferative microenvironment within the BM, favoring differentiation, mobilization, and reconstitution of hematopoiesis.


Asunto(s)
Médula Ósea/metabolismo , Hematopoyesis , Células Madre Hematopoyéticas/citología , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Animales , Movimiento Celular , Factores de Crecimiento Endotelial/metabolismo , Humanos , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones , Neovascularización Fisiológica , Factor A de Crecimiento Endotelial Vascular , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
7.
Bogota, D.C; s.n; ene. 1994. 47 p. tab, graf.
Tesis en Español | LILACS | ID: lil-190155

RESUMEN

El presente estudio se realizó durante los meses de Septiembre de 1990 a Agosto de 1991. Se incluyeron 30 pacientes que cumplieron con los requisitos Heridas comprendidas en la región lumbar, producidas por arma cortapunzante, que llegaron al servicio de urgencias al HRBS durante las primeras 24 horas de producida la lesión, en pacientes con signos vitales estables sin signos abdominales de irritación peritoneal y sin otras lesiones asociadas.A estos pacientes se les realizó el lavado peritoneal para determinar si había o no compromiso intraperitoneal y de ser este positivo llevar a cirugía en forma temprana.Encontramos que todos los pacientes fueron de sexo masculino, con edades comprendidas entre los 17 y 44 años con un promedio de 26 años, en 5 pacientes de los treinta encontramos el lavado peritoneal positivo por lo cual se llevaron a cirugía: 2 de estos pacientes presentaron heridas de bazo y diafragma; 2 pacientes con herida de colon y el restante con herida de mesocolon y hemoperitoneal. Cuatro de los cinco pacientes llegaron dentro de las primeras tres horas de ocurrida la lesión y la realización del lavado y un quinto en las primeras seis horas. Se tomaron a todos los pacientes cuadro hemático y parcial de orina los cuales no tuvieron ningún significado diagnóstico y/o pronóstico. En conclusión el lavado peritoneal fue positivo en el 17 por ciento de nuestros pacientes permitiendo un manejo quirúrgico temprano, en el restante 83 por ciento de los pacientes con examen físico negativo y lavado peritoneal negativo tambien fue importante ayudar este último en cortar la estancia y costos


Asunto(s)
Región Lumbosacra , Lavado Peritoneal , Heridas y Lesiones
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