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1.
Asian J Androl ; 23(3): 240-248, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33533740

RESUMO

Spermatogonial stem cells (SSCs) have great applications in both reproductive and regenerative medicine. Primates including monkeys are very similar to humans with regard to physiology and pathology. Nevertheless, little is known about the isolation, the characteristics, and the culture of primate SSCs. This study was designed to identify, isolate, and culture monkey SSCs. Immunocytochemistry was used to identify markers for monkey SSCs. Glial cell line-derived neurotrophic factor family receptor alpha-1 (GFRA1)-enriched spermatogonia were isolated from monkeys, namely Macaca fascicularis (M. fascicularis), by two-step enzymatic digestion and magnetic-activated cell sorting, and they were cultured on precoated plates in the conditioned medium. Reverse transcription-polymerase chain reaction (RT-PCR), immunocytochemistry, and RNA sequencing were used to compare phenotype and transcriptomes in GFRA1-enriched spermatogonia between 0 day and 14 days of culture, and xenotransplantation was performed to evaluate the function of GFRA1-enriched spermatogonia. SSCs shared some phenotypes with rodent and human SSCs. GFRA1-enriched spermatogonia with high purity and viability were isolated from M. fascicularis testes. The freshly isolated cells expressed numerous markers for rodent SSCs, and they were cultured for 14 days. The expression of numerous SSC markers was maintained during the cultivation of GFRA1-enriched spermatogonia. RNA sequencing reflected a 97.3% similarity in global gene profiles between 0 day and 14 days of culture. The xenotransplantation assay indicated that the GFRA1-enriched spermatogonia formed colonies and proliferated in vivo in the recipient c-KitW/W (W) mutant mice. Collectively, GFRA1-enriched spermatogonia are monkey SSCs phenotypically both in vitro and in vivo. This study suggests that monkey might provide an alternative to human SSCs for basic research and application in human diseases.


Assuntos
Células-Tronco Germinativas Adultas/citologia , Separação Celular/métodos , Macaca fascicularis/classificação , Análise de Variância , Animais , Separação Celular/estatística & dados numéricos , Complicações do Diabetes , Modelos Animais de Doenças , Humanos , Ratos Sprague-Dawley
2.
Acta bioquím. clín. latinoam ; 50(4): 783-790, dic. 2016. ilus, graf, tab
Artigo em Espanhol | LILACS | ID: biblio-837651

RESUMO

Los exosomas son vesículas membranosas extracelulares esenciales en la comunicación intercelular a larga distancia, viajan en los fluidos corporales y entregan mensajes moleculares dirigidos a la mayoría de las células de todo el organismo. La liberación de mensajes vía exosomas ocurre en forma de ADN, ARN o proteínas; dicha liberación se ha asociado a diferentes condiciones fisiológicas normales y patológicas, como el cáncer. Por lo anterior, el aislamiento eficiente y caracterización celular de exosomas de plasma es clave para su uso como biomarcadores no invasivos de diversas enfermedades. En el presente estudio se purificaron exosomas a partir de muestras clínicas de plasmas de pacientes previamente diagnosticados con retinoblastoma y de individuos sanos como control. Los exosomas recuperados fueron caracterizados a nivel celular por microscopia electrónica de transmisión empleando una técnica de criogenia. Para demostrar la correcta purificación de exosomas se confirmó la presencia de las proteínas transmembranales CD63 y CD81 mediante immunoblot. Adicionalmente de los exosomas purificados, se identificaron ARNs pequeños no codificantes llamados microARNs. En general, se describe la purificación y caracterización celular de exosomas obtenidos de plasma humano para su potencial uso como biomarcadores.


Exosomes are small extracellular vesicles essential in intercellular communication; they act as vehicles of broad scope. They are travelling in body fluids and delivering molecular messages to cells in the organism. Messages released by exosomes like DNA, RNA and proteins are associated with different pathological conditions including cancer. Therefore, the efficient isolation and cellular characterization of exosomes from plasma is essential to use them as biomarkers in many diseases. Here, exosomes were purified from patients diagnosed with pediatric cancer and healthy individuals as control. The exosomes recovered were characterized using cryogenic transmission electron microscopy. Moreover, the presence of CD63 and CD81 transmembrane proteins was confirmed using Western blot. Besides, miRNAs presence was identified from exosomes. This work describes a complete technique to isolate and characterize exosomes from human plasma, recognizing their potential as biomarkers.


Os exossomos são vesículas membranosas extracelulares essenciais na comunicação intercelular de longa distância; eles viajam em fluidos corporais e entregam mensagens moleculares dirigidas à maioria das células de todo o organismo. A liberação de mensagens através dos exossomos ocorre em forma de DNA, RNA ou proteínas; essa liberação foi associada a diferentes condições fisiológicas normais e patológicas, tais como o câncer. Por tudo isso, o eficiente isolamento e caracterização celular de exossomos de plasma é chave para sua utilização como biomarcadores não invasivos de várias doenças. No presente estudo, exossomos foram purificados a partir de amostras clínicas de plasmas de pacientes que tinham sido diagnosticados previamente com retinoblastoma e de indivíduos saudáveis como controle. Os exossomos recuperados foram caracterizados a nível celular por microscopia eletrônica de transmissão usando uma técnica de criogenia. Para demonstrar a correta purificação dos exossomos, foi confirmada a presença de proteínas transmembranares CD63 e CD81 usando inmunoblot. Além dos exossomos purificados foram identificados ARNs não codificantes pequenos chamados microARNs. Em geral os métodos de purificação e caracterização celular de exossomos obtidos de plasma humano são descritos por seu potencial utilização como biomarcadores.


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Biomarcadores , Separação Celular/estatística & dados numéricos , Exossomos , Retinoblastoma/diagnóstico , Diagnóstico
3.
Rev. cuba. med. mil ; 44(4): 416-427, oct.-dic. 2015.
Artigo em Espanhol | LILACS, CUMED | ID: lil-777059

RESUMO

La leptospirosis humana es una enfermedad zoonótica de distribución mundial, con frecuencia subdiagnosticada por presentar un amplio espectro de manifestaciones clínicas. El objetivo es presentar una actualización sobre el diagnóstico de la leptospirosis humana. Se consultó la bibliografía disponible sobre el tema en las bases de datos de Scielo, HINARI, Pubmed-Medline y diferentes textos y artículos en los que se profundizaba en el diagnóstico. Las técnicas microbiológicas son la base de la confirmación de la enfermedad. La observación por microscopía de campo oscuro es poco sensible, ya que las leptospiras se pueden confundir con filamentos proteicos u otros artefactos. El aislamiento del agente etiológico constituye la prueba de oro, aunque ofrece un resultado retrospectivo. La reacción en cadena de la polimerasa es un método útil para el diagnóstico rápido de la infección. El diagnóstico serológico cobra vital importancia en esta entidad, pues supera en rapidez, sencillez y bajo costo al cultivo. La microaglutinación con antígenos vivos es la técnica de referencia. Las pruebas rápidas basadas en la inmunocromatografía de flujo lateral son una variante muy útil, ya que ofrecen el resultado entre 5 y 30 minutos.


The human leptospirosis is zoonotic disease with worldwide distribution, frequently present a difficult diagnosis because have a wide spectrum of clinical manifestations. The objective of this work is to present an upgrade on the diagnosis of the human leptospirosis; for it was consulted it the available bibliography on the topic in the databases of Scielo, HINARI, Pubmed-Medline and different texts and articles of the last five years to deepen in the diagnosis. The microbiologic diagnostic is the base of the confirmation of the illness; it depends on the taking of sample in the appropriate moment and the correct indication of the complementary one according to the clinical phase. The observation for microscopy of dark field is not very sensitive since the leptospiras can made a mistake with poetics filaments or other devices. The etiologic agent's isolation constitutes the gold standard test; although offers a retrospective result. The polymerase chain reaction is a method used for the quick diagnosis of the infection, the quantitative variant in real time shows substantial advantages, because it allows the immediate reading and avoids the electrophoresis step, these techniques are not available for its high cost. The serologic diagnostic charges vital importance in this entity, it overcomes in speed, simplicity and low cost to the cultivation; the microagglutinación with a live antigen is considered the reference technique. The detection of IgM for enzyme linked immunobsorbent assay has been broadly used. The rapid tests based on the lateral flow immunochromatography, are a very useful variant, since they offer the result between 5 and 30 minutes.


Assuntos
Humanos , Literatura de Revisão como Assunto , Separação Celular/estatística & dados numéricos , Reação em Cadeia da Polimerase/métodos , Leptospirose/diagnóstico
4.
J Clin Apher ; 30(6): 321-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25619791

RESUMO

It has been shown that it is possible to predict the CD 34+ hematopoietic progenitor cell dose from collection procedures on TerumoBCT COBE Spectra® cell separator platform using simple variables available at the start of the procedure. In this article, we demonstrate that this can be done simply and reliably using TerumoBCT Spectra Optia® ("Optia") cell separator platform with a very close correlation between predicted and actual results (correlation coefficient 0.956). This knowledge can be used to optimize apheresis sessions and to minimize harmful effects and costs. In addition, we have shown differences in collection efficiency between healthy donors and cancer patients undergoing autologous donation. Finally, we have shown a small but significant improvement in collection efficiency for the Optia platform compared with the COBE Spectra platform.


Assuntos
Remoção de Componentes Sanguíneos/instrumentação , Separação Celular/instrumentação , Células-Tronco Hematopoéticas/citologia , Adolescente , Adulto , Idoso , Antígenos CD34/metabolismo , Benchmarking , Remoção de Componentes Sanguíneos/normas , Remoção de Componentes Sanguíneos/estatística & dados numéricos , Contagem de Células , Separação Celular/normas , Separação Celular/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/imunologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Controle de Qualidade , Estudos Retrospectivos
5.
PLoS One ; 8(4): e61774, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23658615

RESUMO

Filtration can achieve circulating tumor cell (CTC) enrichment from blood. Key parameters such as flow-rate, applied pressure, and fixation, vary largely between assays and their influence is not well understood. Here, we used a filtration system, to monitor these parameters and determine their relationships. Whole blood, or its components, with and without spiked tumor cells were filtered through track-etched filters. We characterize cells passing through filter pores by their apparent viscosity; the viscosity of a fluid that would pass with the same flow. We measured a ratio of 5·10(4)∶10(2)∶1 for the apparent viscosities of 15 µm diameter MDA-231 cells, 10 µm white cells and 90 fl red cells passing through a 5 µm pore. Fixation increases the pressure needed to pass cells through 8 µm pores 25-fold and halves the recovery of spiked tumor cells. Filtration should be performed on unfixed samples at a pressure of ∼10 mbar for a 1 cm(2) track-etched filter with 5 µm pores. At this pressure MDA-231 cells move through the filter in 1 hour. If fixation is needed for sample preservation, a gentle fixative should be selected. The difference in apparent viscosity between CTC and blood cells is key in optimizing recovery of CTC.


Assuntos
Separação Celular/estatística & dados numéricos , Filtração/estatística & dados numéricos , Hemorreologia , Células Neoplásicas Circulantes/patologia , Adulto , Linhagem Celular Tumoral , Separação Celular/métodos , Eritrócitos/citologia , Filtração/métodos , Fixadores , Humanos , Leucócitos/citologia , Pessoa de Meia-Idade , Pressão , Viscosidade
6.
Pathol Biol (Paris) ; 60(2): 143-8, 2012 Apr.
Artigo em Francês | MEDLINE | ID: mdl-21123007

RESUMO

Haematopoietic stem cells transplantation, widely used these last decades, represent the ultimate treatment resource for patients with haematological malignancies. Long range success of this treatment is particularly affected by relapse of the initial disease, graft rejection or graft versus host disease. Chimerism analysis after transplantation had been used since several years to document engraftment, to determine the risk of relapse and to adapt therapy promptly when necessary. Usefulness of this analysis for the outcome of transplanted patients, as well as the impact of using high sensitive techniques coupled with specific cell populations sorted have been demonstrated by retrospective studies. Follow-up of chimerism would allow to operate efficiently before the onset of clinical signs in leukaemic patients with high risk of relapse and to control the expression of minimal residual disease when specific molecular markers could not be monitored.


Assuntos
Separação Celular/estatística & dados numéricos , Citometria de Fluxo/estatística & dados numéricos , Transplante de Células-Tronco Hematopoéticas , Quimeras de Transplante , Separação Celular/métodos , Quimerismo , Citometria de Fluxo/métodos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Modelos Biológicos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/estatística & dados numéricos , Quimeras de Transplante/genética , Quimeras de Transplante/fisiologia , Transplante Homólogo
7.
Transfus Med ; 18(5): 296-301, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18937737

RESUMO

The aim of this study was to describe current blood conservation practice during revision hip surgery in Scotland and document practice variation. Revision hip surgery is associated with a high likelihood of blood transfusion. A decrease in the proportion of patients requiring blood transfusion has been documented, but the reasons for this are unclear. Various blood conservation practices are available to clinicians, but the extent to which these are used in Scottish hospitals is not known. A cross-sectional postal survey was sent to all consultant orthopaedic surgeons and consultant anaesthetists participating in revision hip surgery in Scottish hospitals. Responses were received from 92 of 120 (77%) surgeons, and 174 of 216 (81%) anaesthetists (62/92). A total of 62 of 92 (67%) surgeons and 78 of 174 (45%) anaesthetists surveyed participated in revision hip surgery. Blood conservation practice varied widely: 34 of 78 (44%) anaesthetists routinely assessed revision hip patients >or=1 week prior to surgery; 10 of 62 (16%) surgeons and 24 of 78 (31%) anaesthetists routinely used cell salvage; 7 of 78 (9%) anaesthetists and 2 of 62 (3%) surgeons routinely used tranexamic acid; and 45 of 62 (73%) surgeons use a transfusion protocol. A wide variation in the use of blood conservation strategies exists during revision hip surgery in Scotland.


Assuntos
Artroplastia de Quadril/estatística & dados numéricos , Transfusão de Sangue/estatística & dados numéricos , Anestesia/métodos , Anestesiologia/estatística & dados numéricos , Antifibrinolíticos/administração & dosagem , Perda Sanguínea Cirúrgica/prevenção & controle , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Separação Celular/estatística & dados numéricos , Estudos Transversais , Uso de Medicamentos/estatística & dados numéricos , Inquéritos Epidemiológicos , Hemoglobinometria/estatística & dados numéricos , Humanos , Ferro/administração & dosagem , Ortopedia/estatística & dados numéricos , Cuidados Pós-Operatórios , Padrões de Prática Médica/estatística & dados numéricos , Cuidados Pré-Operatórios , Reoperação/métodos , Reoperação/estatística & dados numéricos , Escócia , Inquéritos e Questionários , Ácido Tranexâmico/administração & dosagem
8.
Cuad. Hosp. Clín ; 50(2): 49-54, 2005. tab, graf
Artigo em Espanhol | LILACS, LIBOCS | ID: lil-429033

RESUMO

INTRODUCCIÓN: las células endoteliales pueden proveer información valiosa con respecto a muchos procesos patológicos como la aterosclerosis, inflamación, neoplasia y angiogénesis. Este trabajo describe la primera experiencia boliviana en el aislamiento y cultivo de células endoteliales humanas derivadas de la vena umbilical (HUVEC). MÉTODOS: Un segmento largo de cordón umbilical se utilizó para el aislamiento y fue tratado por digestión con colagenasa. Las células endoteliales fueron desprendidas de la íntima y posteriormente cultivadas en medio de cultivo M199 y suero fetal bovino. Técnicas morfológicas, inmunohistoquímicas y de citometría de flujo fueron utilizadas para identificar estas células. RESULTADOS: Se examinaron las células endoteliales obtenidas por análisis morfológico e inmunohistoquímico. El marcaje con CD34 fue positivo para más del 90% de las células obtenidas por digestión con colagenasa analizado por citometría de flujo. CONCLUSIÓN Se logró aislar y cultivar HUVEC de manera exitosa. Una gran variedad de experimentos y aplicaciones en ciencias biomédicas pueden ser potencialmente factibles.


INTRODUCTION: endothelial cell study yields valuable information concerning many pathologic processes such as atherosclerosis, inflammation, neoplasia and angiogenesis. This paper describes the first Bolivian experience in isolation and culture of human umbilical vein endothelial cells (HUVEC). METHODS: a long segment of the umbilical cord was processed by collagenase digestion. Endothelial cells were detached from intima and further cultured using M199 culture media. Morphologic, immunochemistry and flow cytometry approaches were used to identify these cells. RESULTS: morphologic and immunochemistry analysis of the pool of obtained cells were positive for HUVEC. CD34 staining was positive in more than 90% of the cells obtained by collagenase digestion as assessed by flow cytometry. CONCLUSION: HUVEC were successfully isolated for the first time in Bolivia. A great deal of further experiments and applications in biomedical sciences is possible


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Células/metabolismo , Células/patologia , Separação Celular/classificação , Separação Celular/estatística & dados numéricos , Separação Celular/instrumentação , Separação Celular/métodos , Separação Celular/normas , Citometria de Fluxo/classificação , Citometria de Fluxo/estatística & dados numéricos , Citometria de Fluxo/instrumentação , Citometria de Fluxo/métodos , Técnicas de Cultura de Células/classificação , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos
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