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1.
Sci Rep ; 13(1): 21082, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-38030664

RESUMO

The genetic material encoded on X and Y chromosomes provides the foundation by which biological sex differences are established. Epigenetic regulators expressed on these sex chromosomes, including Kdm6a (Utx), Kdm5c, and Ddx3x have far-reaching impacts on transcriptional control of phenotypic sex differences. Although the functionality of UTY (Kdm6c, the Y-linked homologue of UTX), has been supported by more recent studies, its role in developmental sex differences is not understood. Here we test the hypothesis that UTY is an important transcriptional regulator during development that could contribute to sex-specific phenotypes and disease risks across the lifespan. We generated a random insertion Uty transgenic mouse (Uty-Tg) to overexpress Uty. By comparing transcriptomic profiles in developmental tissues, placenta and hypothalamus, we assessed potential UTY functional activity, comparing Uty-expressing female mice (XX + Uty) with wild-type male (XY) and female (XX) mice. To determine if Uty expression altered physiological or behavioral outcomes, adult mice were phenotypically examined. Uty expression masculinized female gene expression patterns in both the placenta and hypothalamus. Gene ontology (GO) and gene set enrichment analysis (GSEA) consistently identified pathways including immune and synaptic signaling as biological processes associated with UTY. Interestingly, adult females expressing Uty gained less weight and had a greater glucose tolerance compared to wild-type male and female mice when provided a high-fat diet. Utilizing a Uty-overexpressing transgenic mouse, our results provide novel evidence as to a functional transcriptional role for UTY in developing tissues, and a foundation to build on its prospective capacity to influence sex-specific developmental and health outcomes.


Assuntos
Regulação da Expressão Gênica , Transcriptoma , Masculino , Feminino , Animais , Camundongos , Estudos Prospectivos , Perfilação da Expressão Gênica , Camundongos Transgênicos
2.
Elife ; 112022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36441651

RESUMO

Dysregulation of the imprinted H19/IGF2 locus can lead to Silver-Russell syndrome (SRS) in humans. However, the mechanism of how abnormal H19/IGF2 expression contributes to various SRS phenotypes remains unclear, largely due to incomplete understanding of the developmental functions of these two genes. We previously generated a mouse model with humanized H19/IGF2 imprinting control region (hIC1) on the paternal allele that exhibited H19/Igf2 dysregulation together with SRS-like growth restriction and perinatal lethality. Here, we dissect the role of H19 and Igf2 in cardiac and placental development utilizing multiple mouse models with varying levels of H19 and Igf2. We report severe cardiac defects such as ventricular septal defects and thinned myocardium, placental anomalies including thrombosis and vascular malformations, together with growth restriction in mouse embryos that correlated with the extent of H19/Igf2 dysregulation. Transcriptomic analysis using cardiac endothelial cells of these mouse models shows that H19/Igf2 dysregulation disrupts pathways related to extracellular matrix and proliferation of endothelial cells. Our work links the heart and placenta through regulation by H19 and Igf2, demonstrating that accurate dosage of both H19 and Igf2 is critical for normal embryonic development, especially related to the cardiac-placental axis.


Assuntos
Síndrome de Silver-Russell , Animais , Feminino , Camundongos , Gravidez , Modelos Animais de Doenças , Células Endoteliais , Fator de Crescimento Insulin-Like II/genética , Placenta , Placentação , Síndrome de Silver-Russell/genética , Histonas/metabolismo
3.
Diagnostics (Basel) ; 12(8)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36010302

RESUMO

(1) Introduction: The changes in the joint morphology inevitably lead to prosthesis, but the hip pathology is complex. The hip arthroplasty is a therapeutic solution and can be caused, most frequently, by primary and secondary coxarthrosis due to or followed by traumatic conditions. The main aim of this study was to find the method of revision hip prosthesis that preserves as much bone material as possible and has sufficiently good mechanical strength. (2) Materials and Methods: In this study, in a first step, the two revision prostheses were performed on bone components taken from an animal (cow), and then, they were tested on a mechanical testing machine until the prostheses physically failed, and the force causing their failure was determined. (3) Results: These prostheses were then modelled in a virtual environment and tested using the finite element method (FEM) in order to determine their behaviour under loading from normal human gait. Displacement, strain, and stress maps were obtained. (4) Discussion: Discussions on hip revision prostheses, method, and theory analysis are presented at the end of the paper. (5) Conclusions: Important conclusions are drawn based on comparative analyses. The main conclusion shows that the both orthopaedic prostheses provide a very good resistance.

4.
Sci Rep ; 12(1): 240, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997149

RESUMO

Regional optimisation of malaria vector control approaches requires detailed understanding both of the species composition of Anopheles mosquito communities, and how they vary over spatial and temporal scales. Knowledge of vector community dynamics is particularly important in settings where ecohydrological conditions fluctuate seasonally and inter-annually, such as the Barotse floodplain of the upper Zambezi river. DNA barcoding of anopheline larvae sampled in the 2019 wet season revealed the predominance of secondary vector species, with An. coustani comprising > 80% of sampled larvae and distributed ubiquitously across all ecological zones. Extensive larval sampling, plus a smaller survey of adult mosquitoes, identified geographic clusters of primary vectors, but represented only 2% of anopheline larvae. Comparisons with larval surveys in 2017/2018 and a contemporaneous independent 5-year dataset from adult trapping corroborated this paucity of primary vectors across years, and the consistent numerical dominance of An. coustani and other secondary vectors in both dry and wet seasons, despite substantial inter-annual variation in hydrological conditions. This marked temporal consistency of spatial distribution and anopheline community composition presents an opportunity to target predominant secondary vectors outdoors. Larval source management should be considered, alongside prevalent indoor-based approaches, amongst a diversification of vector control approaches to more effectively combat residual malaria transmission.


Assuntos
Anopheles/genética , Mosquitos Vetores/genética , Distribuição Animal , Animais , Anopheles/classificação , Anopheles/crescimento & desenvolvimento , Anopheles/fisiologia , Feminino , Inundações , Larva/genética , Larva/crescimento & desenvolvimento , Larva/fisiologia , Malária , Masculino , Controle de Mosquitos , Mosquitos Vetores/classificação , Mosquitos Vetores/crescimento & desenvolvimento , Mosquitos Vetores/fisiologia , Filogenia , Estações do Ano , Zâmbia
5.
PLoS One ; 14(4): e0214932, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31017924

RESUMO

Most of the Paleolithic art and ornaments discovered in Romania come from the site of Poiana Cireșului. Four Paleolithic layers have been studied at this site-the oldest one belongs to the Early Gravettian period between 30 ka and 31 ka BP. The ornaments discovered in this layer include perforated shells from three species of mollusks: freshwater Lithoglyphus naticoide and Lithoglyphus apertus as well as Homalopoma sanguineum (an exclusively Mediterranean species). Poiana Cireșului is one of the very few Gravettian sites where perforated Homalopoma sanguineum shells were found, and the importance of this discovery is stressed even more by the very long distance between the site and the nearest source located over 900 km away. This find suggests the connection of communities here with the Mediterranean area as well as a possible movement of populations from the south of the continent to the east of the Carpathians with significant implications in understanding human group mobility and the origin of the Early Gravettian in this area. Furthermore, Poiana Cireșului is the only Gravettian settlement where Lithoglyphus naticoides shells were used. The unique association of perforated shells-not found in any other Gravettian settlement-contributes to the identity of the Paleolithic community of Poiana Cireșului through their ornaments.


Assuntos
Arqueologia , Cultura , Identificação Social , História Antiga , Humanos , Romênia
6.
Elife ; 62017 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-29244021

RESUMO

ß- and γ-cytoplasmic actin are nearly indistinguishable in their amino acid sequence, but are encoded by different genes that play non-redundant biological roles. The key determinants that drive their functional distinction are unknown. Here, we tested the hypothesis that ß- and γ-actin functions are defined by their nucleotide, rather than their amino acid sequence, using targeted editing of the mouse genome. Although previous studies have shown that disruption of ß-actin gene critically impacts cell migration and mouse embryogenesis, we demonstrate here that generation of a mouse lacking ß-actin protein by editing ß-actin gene to encode γ-actin protein, and vice versa, does not affect cell migration and/or organism survival. Our data suggest that the essential in vivo function of ß-actin is provided by the gene sequence independent of the encoded protein isoform. We propose that this regulation constitutes a global 'silent code' mechanism that controls the functional diversity of protein isoforms.


Assuntos
Actinas/genética , Actinas/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Edição de Genes , Camundongos
7.
Oxid Med Cell Longev ; 2017: 5213186, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29098061

RESUMO

A number of xenobiotic-inducible cytochrome P450s (CYPs) are now known to be localized in the mitochondrial compartment, though their pharmacological or toxicological roles remain unclear. Here, we show that BNF treatment markedly inhibits liver mitochondrial O2 consumption rate (OCR), ADP-dependent OCR, and also reserve OCR, in wild-type mice but not in Cyp1a1/1a2(-/-) double knockout mice. BNF treatment markedly affected mitochondrial complex I and complex IV activities and also attenuated mitochondrial gene expression. Furthermore, under in vitro conditions, BNF treatment induced cellular ROS production, which was inhibited by mitochondria-targeted antioxidant Mito-CP and CYP inhibitor proadefin, suggesting that most of the ROS production was intramitochondrial and probably involved the catalytic activity of mitochondrial CYP1 enzymes. Interestingly, our results also show that the AHR antagonist resveratrol, markedly attenuated BNF-induced liver mitochondrial defects in wild-type mice, confirming the role of AHR and AHR-regulated CYP1 genes in eliciting mitochondrial dysfunction. These results are consistent with reduced BNF-induced mitochondrial toxicity in Cyp1a1/1a2(-/-) mice and elevated ROS production in COS cells stably expressing CYP1A1. We propose that increased mitochondrial ROS production and respiratory dysfunction are part of xenobiotic toxicity. Resveratrol, a chemopreventive agent, renders protection against BNF-induced toxicity.


Assuntos
Citocromo P-450 CYP1A1/genética , Mitocôndrias/metabolismo , Estilbenos/uso terapêutico , beta-Naftoflavona/metabolismo , Animais , Técnicas de Cultura de Células , Masculino , Camundongos , Camundongos Knockout , Resveratrol , Estilbenos/farmacologia
8.
PLoS One ; 12(9): e0185196, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28934364

RESUMO

A stem cell's epigenome directs cell fate during development, homeostasis, and regeneration. Epigenetic dysregulation can lead to inappropriate cell fate decisions, aberrant cell function, and even cancer. The histone variant macroH2A has been shown to influence gene expression, guide cell fate, and safeguard against genotoxic stress. Interestingly, mice lacking functional macroH2A histones (hereafter referred to as macroH2A DKO) are viable and fertile; yet suffer from increased perinatal death and reduced weight and size compared to wildtype (WT). Here, we ask whether the ostensible reduced vigor of macroH2A DKO mice extends to intestinal stem cell (ISC) function during homeostasis, regeneration, and oncogenesis. Lgr5-eGFP-IRES-CreERT2 or Hopx-CreERT2::Rosa26-LSL-tdTomato ISC reporter mice or the C57BL/6J-Apcmin/J murine intestinal adenoma model were bred into a macroH2A DKO or strain-matched WT background and assessed for ISC functionality, regeneration and tumorigenesis. High-dose (12Gy) whole-body γ-irradiation was used as an injury model. We show that macroH2A is dispensable for intestinal homeostasis and macroH2A DKO mice have similar numbers of active crypt-base columnar ISCs (CBCs). MacroH2A DKO intestine exhibits impaired regeneration following injury, despite having significantly more putative reserve ISCs. DKO reserve ISCs disproportionately undergo apoptosis compared to WT after DNA damage infliction. Interestingly, a macroH2A DKO background does not significantly increase tumorigenesis in the Apcmin model of intestinal adenoma. We conclude that macroH2A influences reserve ISC number and function during homeostasis and regeneration. These data suggest macroH2A enhances reserve ISC survival after DNA damage and thus confers functional robustness to the intestinal epithelium.


Assuntos
Histonas/metabolismo , Intestinos/citologia , Células-Tronco/citologia , Animais , Carcinogênese , Dano ao DNA , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Células HCT116 , Histonas/deficiência , Histonas/genética , Homeostase , Humanos , Mucosa Intestinal/metabolismo , Neoplasias Intestinais/genética , Neoplasias Intestinais/metabolismo , Neoplasias Intestinais/patologia , Intestinos/patologia , Intestinos/fisiologia , Camundongos , Regeneração , Células-Tronco/patologia
9.
Sci Rep ; 7(1): 11323, 2017 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-28900170

RESUMO

Alpha synuclein (α-syn) is a central player in neurodegeneration, but the mechanisms triggering its pathology are not fully understood. Here we found that α-syn is a highly efficient substrate for arginyltransferase ATE1 and is arginylated in vivo by a novel mid-chain mechanism that targets the acidic side chains of E46 and E83. Lack of arginylation leads to increased α-syn aggregation and causes the formation of larger pathological aggregates in neurons, accompanied by impairments in its ability to be cleared via normal degradation pathways. In the mouse brain, lack of arginylation leads to an increase in α-syn's insoluble fraction, accompanied by behavioral changes characteristic for neurodegenerative pathology. Our data show that lack of arginylation in the brain leads to neurodegeneration, and suggests that α-syn arginylation can be a previously unknown factor that facilitates normal α-syn folding and function in vivo.


Assuntos
Arginina/metabolismo , Encéfalo/fisiologia , Doenças Neurodegenerativas/metabolismo , alfa-Sinucleína/metabolismo , Sequência de Aminoácidos , Aminoaciltransferases/genética , Aminoaciltransferases/metabolismo , Animais , Células Cultivadas , Modelos Animais de Doenças , Humanos , Espectrometria de Massas , Camundongos , Camundongos Knockout , Modelos Biológicos , Doenças Neurodegenerativas/patologia , Doenças Neurodegenerativas/prevenção & controle , Neurônios/metabolismo , Neurônios/patologia , Peptídeos/química , Peptídeos/metabolismo , Agregados Proteicos , Agregação Patológica de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Proteólise , Proteínas Recombinantes , Especificidade por Substrato , alfa-Sinucleína/química
10.
Biomed Opt Express ; 2(8): 2372-82, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21833374

RESUMO

We demonstrate for the first time that optical coherence tomography (OCT) imaging can reliably distinguish between morphologic features of low risk pancreatic cysts (i.e., pseudocysts and serous cystadenomas) and high risk pancreatic cysts (i.e., mucinous cystic neoplasms and intraductal papillary mucinous neoplasms). In our study fresh pancreatectomy specimens (66) from patients with cystic lesions undergoing surgery were acquired and examined with OCT. A training set of 20 pathology-OCT correlated tissue specimens were used to develop criteria for differentiating between low and high risk cystic lesions. A separate (validation) set of 46 specimens were used to test the OCT criteria by three clinicians, blinded to histopathology findings. Histology was finally used as a 'gold' standard for testing OCT findings. OCT was able to reveal specific morphologic features of pancreatic cysts and thus to differentiate between low-risk and high-risk cysts with over 95% sensitivity and specificity. This pilot study suggests that OCT could be used by clinicians in the future to more reliably differentiate between benign and potentially malignant pancreatic cysts. However, in vivo use of OCT requires a probe that has to fit the bore of the pancreas biopsy needle. Therefore, we have developed such probes and planned to start an in vivo pilot study within the very near future.

11.
PLoS One ; 4(11): e7734, 2009 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-19890395

RESUMO

Posttranslational protein arginylation mediated by Ate1 is essential for cardiovascular development, actin cytoskeleton functioning, and cell migration. Ate1 plays a role in the regulation of cytoskeleton and is essential for cardiovascular development and angiogenesis--capillary remodeling driven by in-tissue migration of endothelial cells. To address the role of Ate1 in cytoskeleton-dependent processes and endothelial cell function during development, we produced a conditional mouse knockout with Ate1 deletion driven by Tek endothelial receptor tyrosine kinase promoter expressed in the endothelium and in the germ line. Contrary to expectations, Tek-Ate1 mice were viable and had no visible angiogenesis-related phenotypes; however, these mice showed reproductive defects, with high rates of embryonic lethality in the second generation, at stages much earlier than the complete Ate1 knockout strain. While some of the early lethality originated from the subpopulation of embryos with homozygous Tek-Cre transgene--a problem that has not previously been reported for this commercial mouse strain--a distinct subpopulation of embryos had lethality at early post-implantation stages that could be explained only by a previously unknown defect in gametogenesis originating from Tek-driven Ate1 deletion in premeiotic germs cells. These results demonstrate a novel role of Ate1 in germ cell development.


Assuntos
Aminoaciltransferases/genética , Gametogênese/genética , Deleção de Genes , Regiões Promotoras Genéticas , Receptores Proteína Tirosina Quinases/genética , Actinas/metabolismo , Animais , Movimento Celular , Citoesqueleto/metabolismo , Implantação do Embrião , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas , Masculino , Camundongos , Camundongos Knockout , Receptor TIE-2
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