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1.
An. Facultad Med. (Univ. Repúb. Urug., En línea) ; 6(2): 25-34, dic. 2019. ilus, graf
Artículo en Español | LILACS, UY-BNMED, BNUY | ID: biblio-1291263

RESUMEN

El estudio de la megacariopoyesis humana se ha visto obstaculizado por la relativa escasez de megacariocitos en la médula ósea (0,05-0,2 % de las células medulares), lo que ha llevado a la optimización de protocolos de expansión in vitro a partir de precursores de diversos orígenes (cordón umbilical, médula ósea y sangre periférica con o sin movilización previa). Los cultivos celulares a partir de precursores han permitido la producción y el estudio tanto de megacariocitos así como de proplaquetas y plaquetas Sin embargo, la producción in vitro óptima de megacariocitos que culminen todos los estadios de diferenciación es un reto aún no resuelto. En este trabajo reportamos los hallazgos concernientes a la determinación de las condiciones y concentraciones de trombopoyetina para lograr una óptima relación entre la cantidad de trombopoyetina empleada y el porcentaje y grado de diferenciación megacariocítica en muestras obtenidas de cinco donantes alogénicos aceptados para trasplante de médula ósea.


The study of human megakaryocytopoiesis has been hampered by the relative scarcity of megakaryocytes in bone marrow (0.05-0.2 % of medullary cells), which has led to the optimization of protocols of in vitro expansion of precursors from diverse sources (umbilical cord, bone marrow and peripheral blood with or without previous mobilization). Cell cultures from different precursors have allowed the production and study of megakaryocytes as well as proplatelets and platelets. However, the in vitro production of megakaryocytes that culminate all stages of differentiation is a challenge that has not yet been resolved. In this work we report the findings related to the determination of thrombopoietin treatment conditions and concentrations to achieve an optimal relationship between the amount of thrombopoietin and the percentage and degree of megakaryocytic differentiation in five allogeneic donors that were accepted for bone marrow transplantation.


O estudo da megacariopoiese humana tem sido dificultado pela relativa escassez de megacariócitos na medula óssea (0,05-0,2 % das células medulares), o que levou à otimização dos protocolos de expansão in vitro a partir de precursores de diversas origens (cordão umbilical, medula óssea e sangue periférico com ou sem mobilização prévia). Culturas de células a partir de precursores permitiram a produção e o estudo tanto de megacariócitos e de proplaquetas e plaquetas. No entanto, a produção ótima in vitro de megacariócitos que culminam em todas as fases de diferenciação é um desafio ainda não resolvido. Neste trabalho, relatamos as descobertas relativas à determinação das condições e concentrações de trombopoietina para obter uma relação ótima entre a quantidade de trombopoietina usada e a taxa e o grau de diferenciação megacariocítica em amostras obtidas de cinco doadores alogênicos aceitos para transplante de medula óssea.


Asunto(s)
Humanos , Trombopoyetina/análisis , Megacariocitos/citología , Antígenos CD34/análisis , Células Cultivadas/citología , Leucaféresis , Glicoproteína IIb de Membrana Plaquetaria/análisis , Integrina beta3/análisis , Técnicas de Cultivo/métodos
2.
JBRA Assist Reprod ; 21(3): 196-202, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28837027

RESUMEN

OBJECTIVE: Alterations in endometrial receptivity may be involved in the etiopathogenesis of endometriosis-related infertility. The literature has suggested that patients with endometriosis present progestin resistance, which could affect embryo implantation. We question the presence of alterations in the expression of the progesterone receptor gene (PGR) and the genes related to endometrium-embryo interaction regulated by progesterone. This pilot study compared the expression of PGR, HBEGF, ITGAV, ITGB3, and SPP1 genes in eutopic endometrium during the implantation window (IW) in infertile women with endometriosis with that observed in the endometrium of fertile and infertile controls. METHODS: In this prospective case-control study, endometrial biopsies were performed during the IW in patients aged between 18 and 45 years old, with regular cycles and without endocrine/systemic dysfunctions, divided into endometriosis (END), infertile control (IC) and fertile control (FC) groups. Total RNA extraction, cDNA synthesis, and gene expression analysis by Real-Time PCR were performed. We assessed the size of the difference that our series was powered to detect. RESULTS: From the 687 patients who underwent diagnostic videolaparoscopy or tubal ligation at the University Hospital, 130 were eligible. Of these, 32 had endometrial samples collected, with 17 confirmed in the IW. Fifteen samples (5 END, 5 IC and 5 FC) were analyzed. There was no significant difference in the expression of any studied gene. Our sample size allowed us to identify or discard large differences (two standard deviations) among the groups. CONCLUSION: Endometriosis doesn't cause large changes in the endometrial expression of PGR, HBEGF, ITGAV, ITGB3 and SPP1 during the IW.


Asunto(s)
Implantación del Embrión , Endometriosis/epidemiología , Endometrio/metabolismo , Infertilidad Femenina/epidemiología , Adulto , Endometriosis/metabolismo , Endometriosis/terapia , Femenino , Factor de Crecimiento Similar a EGF de Unión a Heparina/análisis , Factor de Crecimiento Similar a EGF de Unión a Heparina/genética , Factor de Crecimiento Similar a EGF de Unión a Heparina/metabolismo , Humanos , Infertilidad Femenina/metabolismo , Infertilidad Femenina/terapia , Integrina beta3/análisis , Integrina beta3/genética , Integrina beta3/metabolismo , Osteopontina/análisis , Osteopontina/genética , Osteopontina/metabolismo , Proyectos Piloto , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Progesterona/análisis , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo
3.
Int J Exp Pathol ; 88(3): 191-8, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17504449

RESUMEN

Pleomorphic adenoma (PA) and adenoid cystic carcinoma (ACC) are the commonest benign and malignant salivary gland tumours respectively. Interactions between cells and extracellular matrix of PA and ACC, partially mediated by integrins, are important in their biology. The expression of integrins is regulated by numerous factors, amongst them, transforming growth factor beta1 (TGFbeta1). Our study investigated the effects of TGFbeta1 on the expression of integrin beta subunits in vitro and on the expression of cytoskeletal proteins of cells derived from PA and ACC. The expression of cytoskeletal differentiation markers and integrins was assessed using immunofluorescence. ELISA assays were employed to quantitate the expression integrins and MTT assays evaluated the mitochondrial activity of cells stimulated with TGFbeta1. PA cells showed increased expression of integrins and de novo expression of differentiation markers upon TGFbeta1 stimulation. ACC cells were less responsive to such stimulation. This may reflect important differences in the biological behaviour of benign and malignant cells.


Asunto(s)
Adenoma Pleomórfico/metabolismo , Carcinoma Adenoide Quístico/metabolismo , Integrinas/metabolismo , Neoplasias de la Parótida/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Adulto , Antígenos de Diferenciación/análisis , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Citoesqueleto/metabolismo , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Integrina beta1/análisis , Integrina beta1/metabolismo , Integrina beta3/análisis , Integrina beta3/metabolismo , Integrina beta4/análisis , Integrina beta4/metabolismo , Integrinas/análisis , Persona de Mediana Edad , Estimulación Química , Células Tumorales Cultivadas
4.
Oral Dis ; 10(5): 277-82, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15315644

RESUMEN

OBJECTIVE: To analyze integrin expression and distribution in different histological types of ameloblastoma, compared with dental germ, dental lamina and adult lining epithelium. MATERIALS AND METHODS: Three-micrometer sections from paraffin-embedded specimens were evaluated employing a streptavidin-biotin immunohistochemical method and anti-integrin alpha2, alpha3, alpha5, alphav, beta1, beta3 and beta4 antibodies. RESULTS: All integrins were present in all specimens, exhibiting different patterns. In follicular ameloblastoma, the integrin staining was stronger in the periphery while integrin alpha2 was not present in the central cells. Acanthomatous ameloblastoma showed a similar pattern, with positive staining for integrins alpha3, alpha5, alphav, beta1 and beta4 in the metaplastic cells. In the unicystic, integrin staining was uniform except for integrins alpha5 and beta3 which showed weaker staining in the upper layers. In the plexiform ameloblastoma, dental germ and lamina integrin staining was uniform. In the adult lining epithelium, staining for integrins alpha2, alpha5 and beta4 was confined to the basal layer, while integrins alphav and beta3 were present in the basal and parabasal, with integrins alpha3 and beta1 in the upper layers. CONCLUSION: Acanthomatous, follicular and unicystic ameloblastomas showed integrin staining patterns similar to the adult lining epithelium while the plexiform ameloblastoma was similar to the dental germ and lamina.


Asunto(s)
Ameloblastoma/patología , Cadenas alfa de Integrinas/análisis , Cadenas beta de Integrinas/análisis , Mucosa Bucal/patología , Germen Dentario/patología , Adulto , Ameloblastoma/clasificación , Anticuerpos , Membrana Basal/patología , Colorantes , Epitelio/patología , Humanos , Inmunohistoquímica , Integrina alfa2/análisis , Integrina alfa3/análisis , Integrina alfa5/análisis , Integrina alfaV/análisis , Integrina beta1/análisis , Integrina beta3/análisis , Integrina beta4/análisis , Metaplasia
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