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1.
Data, v. 6, n. 3, 29, mar. 2021
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3651

RESUMEN

The development of studies, projects, and technologies that contribute to the understanding and preservation of plant biodiversity is becoming highly necessary, as well as tools and software platforms that enable the storage and classification of information resulting from studies on biodiversity. This work presents LeafLive-DB, a software platform that helps map and characterize species from the Brazilian plant biodiversity, offering the possibility of worldwide distribution. Developed by Brazilian and Peruvians researchers, this platform, which is available in its first version, features some functions for consulting and registering plant species and their taxonomy, among other information, through intuitive interfaces and an environment that promotes collaboration and data and research sharing. The platform innovates in data processing, functionality, and development architecture. It has ten thousand registers, and it should start to be distributed in partnership with schools and higher education institutions.

2.
PLoS One ; 10(11): e0140999, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26540511

RESUMEN

Aneuploid embryos diagnosed by FISH-based preimplantation genetic screening (PGS) have been shown to yield euploid lines of human embryonic stem cells (hESCs) with a relatively high frequency. Given that the diagnostic procedure is usually based on the analysis of 1-2 blastomeres of 5 to 10-cell cleavage-stage embryos, mosaicism has been a likely explanation for the phenomena. However, FISH-based PGS can have a significant rate of misdiagnosis, and therefore some of those lines may have been derived from euploid embryos misdiagnosed as aneuploid. More recently, coupling of trophectoderm (TE) biopsy at the blastocyst stage and array-CGH lead to a more informative form of PGS. Here we describe the establishment of a new line of hESCs from an embryo with a 43,XX,dup(9q),+12,-14,-15,-18,-21 chromosomal content based on array-CGH of TE biopsy. We show that, despite the complex chromosomal abnormality, the corresponding hESC line BR-6 is euploid (46,XX). Single nucleotide polymorphism analysis showed that the embryo's missing chromosomes were not duplicated in BR-6, suggesting the existence of extensive mosaicism in the TE lineage.


Asunto(s)
Células Madre Embrionarias/fisiología , Ploidias , Línea Celular , Análisis Citogenético , Embrión de Mamíferos/citología , Citometría de Flujo , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Polimorfismo de Nucleótido Simple/genética
3.
World J Stem Cells ; 7(3): 649-56, 2015 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-25914771

RESUMEN

Normal mouse pluripotent stem cells were originally derived from the inner cell mass (ICM) of blastocysts and shown to be the in vitro equivalent of those pre-implantation embryonic cells, and thus were called embryonic stem cells (ESCs). More than a decade later, pluripotent cells were isolated from the ICM of human blastocysts. Despite being called human ESCs, these cells differ significantly from mouse ESCs, including different morphology and mechanisms of control of pluripotency, suggesting distinct embryonic origins of ESCs from the two species. Subsequently, mouse pluripotent stem cells were established from the ICM-derived epiblast of post-implantation embryos. These mouse epiblast stem cells (EpiSCs) are morphological and epigenetically more similar to human ESCs. This raised the question of whether cells from the human ICM are in a more advanced differentiation stage than their murine counterpart, or whether the available culture conditions were not adequate to maintain those human cells in their in vivo state, leading to a transition into EpiSC-like cells in vitro. More recently, novel culture conditions allowed the conversion of human ESCs into mouse ESC-like cells called naïve (or ground state) human ESCs, and the derivation of naïve human ESCs from blastocysts. Here we will review the characteristics of each type of pluripotent stem cells, how (and whether) these relate to different stages of embryonic development, and discuss the potential implications of naïve human ESCs in research and therapy.

4.
Stem Cell Rev Rep ; 10(4): 472-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24633531

RESUMEN

One of the differences between murine and human embryonic stem cells (ESCs) is the epigenetic state of the X chromosomes in female lines. Murine ESCs (mESCs) present two transcriptionally active Xs that will undergo the dosage compensation process of XCI upon differentiation, whereas most human ESCs (hESCs) spontaneously inactivate one X while keeping their pluripotency. Whether this reflects differences in embryonic development of mice and humans, or distinct culture requirements for the two kinds of pluripotent cells is not known. Recently it has been shown that hESCs established in physiological oxygen levels are in a stable pre-XCI state equivalent to that of mESCs, suggesting that culture in low oxygen concentration is enough to preserve that epigenetic state of the X chromosomes. Here we describe the establishment of two new lines of hESCs under physiological oxygen level and the characterization of the XCI state in the 46,XX line BR-5. We show that a fraction of undifferentiated cells present XIST RNA accumulation and single H3K27me foci, characteristic of the inactive X. Moreover, analysis of allele specific gene expression suggests that pluripotent BR-5 cells present completely skewed XCI. Our data indicate that physiological levels of oxygen are not sufficient for the stabilization of the pre-XCI state in hESCs.


Asunto(s)
Cromosomas Humanos X , Células Madre Embrionarias/metabolismo , Oxígeno/metabolismo , Células Madre Pluripotentes/metabolismo , Inactivación del Cromosoma X , Animales , Diferenciación Celular , Células Cultivadas , Análisis Citogenético , Células Madre Embrionarias/citología , Femenino , Histonas/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones SCID , Células Madre Pluripotentes/citología , ARN Largo no Codificante/metabolismo , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Teratoma/metabolismo , Teratoma/patología
5.
Arq. ciências saúde UNIPAR ; 14(3)set.-dez. 2010. ilus
Artículo en Portugués | LILACS | ID: lil-621329

RESUMEN

A Síndrome do Impacto é uma das doenças do manguito rotador que mais frequentemente provoca dor e disfunção no ombro. Sua etiologia varia desde a impactação dos tecidos moles com estruturas rígidas do ombro durante elevação do braço, microtraumas repetidos, anormalidades anatômicas do acrômio, à degeneração de tendões do manguito rotador. Questiona-se também a possibilidade de desequilíbrios de força entre os músculos rotadores internos e externos ser uma possível causa. Desse modo, o objetivo deste estudo foi verificar a presença de desequilíbrios musculares do manguito rotador, em sujeitos portadores de síndrome do impacto. Com o uso de uma célula de carga foram feitos testes de força muscular isométrica dos músculos do manguito rotador nos ombros lesados, nos contralaterais e em sujeitos controle. Posteriormente, os dados foram submetidos à análise estatística por meio da Análise de Variância (ANOVA) e teste de Tukey. Observou-se diferença estatística significativa ao se comparar o membro lesado com o não lesado, respectivamente em rotação externa nas posições neutra e à 30º (p<0,001). Conclui-se então que os indivíduos com Síndrome do Impacto possuem desequilíbrio de força muscular em rotação externa ao comparar com o lado contralateral.


Impingement Syndrome is one of the diseases of the rotator cuff that frequently provoke pain and dysfunction in the shoulder. Several can be its etiologies from the impingement of the soft tissues with rigid structures of the shoulder during elevation of the arm, repeated microtraumas, acromial anatomical abnormalities to the degeneration of rotator cuff tendons. The possibility of unbalances of force is questioned among the muscles internal and external rotator of being another possible cause. The objective of this study was to verify the presence of muscular unbalances of the rotator cuff in individuals with shoulder impingement. With the use of a load cell were made tests of isometric muscular force of the rotator cuff muscles in the injured shoulders, in the contralateral ones and in individual control. Later the data were submitted to the analysis statistical through the Analysis of Variance (ANOVA) and Tukey test. It was observed significant statistics differences when comparing the member harmed with the no harmed, respectively in rotation it expresses in the neutral positions and at 30º (p <0,001). It is possible to conclude that the individuals with Syndrome of the Impact possess unbalance of muscular force in rotation it is expressed when comparing with the contralateral side.


Asunto(s)
Humanos , Masculino , Femenino , Manguito de los Rotadores/fisiología , Manguito de los Rotadores/lesiones
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