Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
1.
Neonatology ; : 1-8, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38934161

RESUMO

INTRODUCTION: The SafeBoosC-III trial investigated the effect of cerebral oximetry-guided treatment in the first 72 h after birth on mortality and severe brain injury diagnosed by cranial ultrasound in extremely preterm infants (EPIs). This ancillary study evaluated the effect of cerebral oximetry on global brain injury as assessed by magnetic resonance imaging (MRI) at term equivalent age (TEA). METHODS: MRI scans were obtained between 36 and 44.9 weeks PMA. The Kidokoro score was independently evaluated by two blinded assessors. The intervention effect was assessed using the nonparametric Wilcoxon rank sum test for median difference and 95% Hodges-Lehmann (HL) confidence intervals (CIs). The intraclass correlation coefficient (ICC) was used to assess the agreement between the assessors. RESULTS: A total of 210 patients from 8 centers were included, of whom 121 underwent MRI at TEA (75.6% of alive patients): 57 in the cerebral oximetry group and 64 in the usual care group. There was an excellent correlation between the assessors for the Kidokoro score (ICC agreement: 0.93, 95% CI: 0.91-0.95). The results showed no significant differences between the cerebral oximetry group (median 2, interquartile range [IQR]: 1-4) and the usual care group (median 3, IQR: 1-4; median difference -1 to 0, 95% HLCI: -1 to 0; p value 0.1196). CONCLUSIONS: In EPI, the use of cerebral oximetry-guided treatment did not lead to significant alterations in brain injury, as determined by MRI at TEA. The strong correlation between the assessors highlights the potential of the Kidokoro score in multicenter trials.

2.
Nat Struct Mol Biol ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834912

RESUMO

XIST (X-inactive specific transcript) long noncoding RNA (lncRNA) is responsible for X chromosome inactivation (XCI) in placental mammals, yet it accumulates on both X chromosomes in human female preimplantation embryos without triggering X chromosome silencing. The XACT (X-active coating transcript) lncRNA coaccumulates with XIST on active X chromosomes and may antagonize XIST function. Here, we used human embryonic stem cells in a naive state of pluripotency to assess the function of XIST and XACT in shaping the X chromosome chromatin and transcriptional landscapes during preimplantation development. We show that XIST triggers the deposition of polycomb-mediated repressive histone modifications and dampens the transcription of most X-linked genes in a SPEN-dependent manner, while XACT deficiency does not significantly affect XIST activity or X-linked gene expression. Our study demonstrates that XIST is functional before XCI, confirms the existence of a transient process of X chromosome dosage compensation and reveals that XCI and dampening rely on the same set of factors.

3.
Int J Neonatal Screen ; 9(2)2023 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-37218889

RESUMO

Anti-Kell alloimmunisation is a potentially severe minor blood group type incompatibility, not only as a cause of haemolytic disease of the foetus and newborn, but also due to the destruction of red blood cells (RBC) and mature form in the bone marrow with the subsequent hyporegenerative anaemia. In severe cases and when the foetus shows signs of anaemia, an intrauterine transfusion (IUT) may be necessary. When repeated, this treatment can suppress erythropoiesis and worsen the anaemia. We report the case of a newborn who required four IUTs plus an additional RBC transfusion at one month of life due to late onset anaemia. The identification of an adult haemoglobin profile with a complete absence of foetal haemoglobin in the patient's newborn screening samples at 2 and 10 days of life warned us of a possible late anaemia. The newborn was successfully treated with transfusion, oral supplements and subcutaneous erythropoietin. A blood sample taken at 4 months of life showed the expected haemoglobin profile for that age with a foetal haemoglobin of 17.7%. This case illustrates the importance of a close follow-up of these patients, as well as the usefulness of the haemoglobin profile screening as a tool for anaemia assessment.

4.
N Engl J Med ; 388(16): 1501-1511, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37075142

RESUMO

BACKGROUND: The use of cerebral oximetry monitoring in the care of extremely preterm infants is increasing. However, evidence that its use improves clinical outcomes is lacking. METHODS: In this randomized, phase 3 trial conducted at 70 sites in 17 countries, we assigned extremely preterm infants (gestational age, <28 weeks), within 6 hours after birth, to receive treatment guided by cerebral oximetry monitoring for the first 72 hours after birth or to receive usual care. The primary outcome was a composite of death or severe brain injury on cerebral ultrasonography at 36 weeks' postmenstrual age. Serious adverse events that were assessed were death, severe brain injury, bronchopulmonary dysplasia, retinopathy of prematurity, necrotizing enterocolitis, and late-onset sepsis. RESULTS: A total of 1601 infants underwent randomization and 1579 (98.6%) were evaluated for the primary outcome. At 36 weeks' postmenstrual age, death or severe brain injury had occurred in 272 of 772 infants (35.2%) in the cerebral oximetry group, as compared with 274 of 807 infants (34.0%) in the usual-care group (relative risk with cerebral oximetry, 1.03; 95% confidence interval, 0.90 to 1.18; P = 0.64). The incidence of serious adverse events did not differ between the two groups. CONCLUSIONS: In extremely preterm infants, treatment guided by cerebral oximetry monitoring for the first 72 hours after birth was not associated with a lower incidence of death or severe brain injury at 36 weeks' postmenstrual age than usual care. (Funded by the Elsass Foundation and others; SafeBoosC-III ClinicalTrials.gov number, NCT03770741.).


Assuntos
Lactente Extremamente Prematuro , Doenças do Prematuro , Oximetria , Humanos , Lactente , Recém-Nascido , Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/etiologia , Displasia Broncopulmonar/etiologia , Circulação Cerebrovascular , Doenças do Prematuro/diagnóstico , Doenças do Prematuro/mortalidade , Doenças do Prematuro/terapia , Oximetria/métodos , Cérebro , Ultrassonografia , Retinopatia da Prematuridade/etiologia , Enterocolite Necrosante/etiologia , Sepse Neonatal/etiologia
5.
Nucleic Acids Res ; 51(5): 2177-2194, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36727460

RESUMO

X chromosome inactivation (XCI) is an essential process, yet it initiates with remarkable diversity in various mammalian species. XIST, the main trigger of XCI, is controlled in the mouse by an interplay of lncRNA genes (LRGs), some of which evolved concomitantly to XIST and have orthologues across all placental mammals. Here, we addressed the functional conservation of human orthologues of two such LRGs, FTX and JPX. By combining analysis of single-cell RNA-seq data from early human embryogenesis with various functional assays in matched human and mouse pluripotent stem- or differentiated post-XCI cells, we demonstrate major functional differences for these orthologues between species, independently of primary sequence conservation. While the function of FTX is not conserved in humans, JPX stands as a major regulator of XIST expression in both species. However, we show that different entities of JPX control the production of XIST at various steps depending on the species. Altogether, our study highlights the functional versatility of LRGs across evolution, and reveals that functional conservation of orthologous LRGs may involve diversified mechanisms of action. These findings represent a striking example of how the evolvability of LRGs can provide adaptative flexibility to constrained gene regulatory networks.


Assuntos
Placenta , RNA Longo não Codificante , Gravidez , Humanos , Feminino , Camundongos , Animais , Placenta/metabolismo , Inativação do Cromossomo X/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Mamíferos/genética , Embrião de Mamíferos/metabolismo
7.
Biochem Soc Trans ; 49(6): 2549-2560, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34882219

RESUMO

X-inactive-specific transcript (Xist) is a long non-coding RNA (lncRNA) essential for X-chromosome inactivation (XCI) in female placental mammals. Thirty years after its discovery, it is still puzzling how this lncRNA triggers major structural and transcriptional changes leading to the stable silencing of an entire chromosome. Recently, a series of studies in mouse cells have uncovered domains of functional specialization within Xist mapping to conserved tandem repeat regions, known as Repeats A-to-F. These functional domains interact with various RNA binding proteins (RBPs) and fold into distinct RNA structures to execute specific tasks in a synergistic and coordinated manner during the inactivation process. This modular organization of Xist is mostly conserved in humans, but recent data point towards differences regarding functional specialization of the tandem repeats between the two species. In this review, we summarize the recent progress on understanding the role of Xist repetitive blocks and their involvement in the molecular mechanisms underlying XCI. We also discuss these findings in the light of the similarities and differences between mouse and human Xist.


Assuntos
RNA Longo não Codificante/genética , Sequências de Repetição em Tandem , Animais , Inativação Gênica , Humanos , Camundongos , Proteínas do Grupo Polycomb/metabolismo , Transcrição Gênica , Inativação do Cromossomo X
8.
Blood Transfus ; 19(6): 510-517, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33370228

RESUMO

BACKGROUND: Preterm infants born earlier than 32 weeks of gestational age (GA) often need red blood cell (RBC) transfusions, which have been associated with an increased incidence of complications of prematurity, due to changes in tissue oxygenation. Transfusion of umbilical cord blood (UCB) could be beneficial for this group. The aims of this study were: (i) to determine the RBC transfusion needs in infants <32 weeks in Hospital Clinic of Barcelona; (ii) to identify the target GA group that would benefit most from UCB transfusion; and (iii) to assess the current availability of UCB as a potential source of RBC transfusion for these premature infants in our tertiary referral blood bank. MATERIAL AND METHODS: A retrospective observational study was performed on infants born at <32 weeks GA, divided into two groups: (i) extremely low gestational age neonates (ELGAN) (from 230 to 276 weeks) and (ii) very preterm neonates (VPN) (from 280 to 316 weeks). Their complications and transfusion rates were compared. Processing and availability of UCB samples in the reference blood bank were assessed. RESULTS: Overall, 1,651 infants <32 weeks GA were admitted in the study period. While 12.5% of VPN received at least one RBC transfusion, the percentage increased to 60% among the ELGAN. Retinopathy of prematurity and bronchopulmonary dysplasia were diagnosed more frequently in the ELGAN group (p<0.001) than in the VPN group. The annual average volume of RBC transfusion in our study group was 1.35 L (95% CI: 1.07-1.64). The reference blood bank was able to produce 16 L (95% CI: 14-18) of UCB-RBC per year. CONCLUSION: Considering the data obtained about RBC transfusion needs and morbidities, the ELGAN group has been identified as the target group that would benefit most from UCB-RBC transfusions. We have demonstrated that our blood bank is able to produce enough RBC from UCB. Randomised control trials are warranted to study the potential benefits of UCB compared to adult blood for RBC transfusions.


Assuntos
Transfusão de Eritrócitos , Sangue Fetal , Estudos de Viabilidade , Humanos , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro
9.
Nat Commun ; 10(1): 5652, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31827084

RESUMO

Transposable elements (TEs) have been proposed to play an important role in driving the expansion of gene regulatory networks during mammalian evolution, notably by contributing to the evolution and function of long non-coding RNAs (lncRNAs). XACT is a primate-specific TE-derived lncRNA that coats active X chromosomes in pluripotent cells and may contribute to species-specific regulation of X-chromosome inactivation. Here we explore how different families of TEs have contributed to shaping the XACT locus and coupling its expression to pluripotency. Through a combination of sequence analysis across primates, transcriptional interference, and genome editing, we identify a critical enhancer for the regulation of the XACT locus that evolved from an ancestral group of mammalian endogenous retroviruses (ERVs), prior to the emergence of XACT. This ERV was hijacked by younger hominoid-specific ERVs that gave rise to the promoter of XACT, thus wiring its expression to the pluripotency network. This work illustrates how retroviral-derived sequences may intervene in species-specific regulatory pathways.


Assuntos
Retrovirus Endógenos/genética , Elementos Facilitadores Genéticos , Primatas/virologia , RNA Longo não Codificante/genética , Retroviridae/genética , Animais , Elementos de DNA Transponíveis , Retrovirus Endógenos/metabolismo , Evolução Molecular , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Interações Hospedeiro-Patógeno , Humanos , Filogenia , Primatas/classificação , Primatas/genética , RNA Longo não Codificante/metabolismo , Retroviridae/metabolismo , Especificidade da Espécie
11.
Nutrients ; 11(3)2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30845641

RESUMO

Vegetarian and vegan diets have increased worldwide in the last decades, according to the knowledge that they might prevent coronary heart disease, cancer, and type 2 diabetes. Althought plant-based diets are at risk of nutritional deficiencies such as proteins, iron, vitamin D, calcium, iodine, omega-3, and vitamin B12, the available evidence shows that well planned vegetarian and vegan diets may be considered safe during pregnancy and lactation, but they require a strong awareness for a balanced intake of key nutrients. A review of the scientific literature in this field was performed, focusing specifically on observational studies in humans, in order to investigate protective effects elicited by maternal diets enriched in plant-derived foods and possible unfavorable outcomes related to micronutrients deficiencies and their impact on fetal development. A design of pregestational nutrition intervention is required in order to avoid maternal undernutrition and consequent impaired fetal growth.


Assuntos
Dieta Vegana/efeitos adversos , Dieta Vegetariana/efeitos adversos , Doenças do Recém-Nascido/etiologia , Desnutrição/etiologia , Complicações na Gravidez/etiologia , Feminino , Retardo do Crescimento Fetal/etiologia , Humanos , Recém-Nascido , Lactação , Fenômenos Fisiológicos da Nutrição Materna , Micronutrientes/deficiência , Necessidades Nutricionais , Gravidez
12.
Nanoethics ; 12(3): 269-281, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30546499

RESUMO

There is a growing recognition within cognitive enhancement and neuroethics debates of the need for greater emphasis on cognitive artefacts. This paper aims to contribute to this broadening and expansion of the cognitive-enhancement and neuroethics debates by focusing on a particular form of relation or coupling between humans and cognitive artefacts: interaction-dominance. We argue that interaction-dominance as an emergent property of some human-cognitive artefact relations has important implications for understanding the attribution and distribution of causal and other forms of responsibility as well as agency relating to the actions of human-cognitive artefact couplings. Interaction-dominance is both indicated and constituted by the phenomenon of "pink noise". Understanding the role of noise in this regard will establish a necessary theoretical groundwork for approaching the ethical and political dimensions of relations between human cognition and digital cognitive artefacts. We argue that pink noise in this context plays a salient role in the practical, ethical, and political evaluation of coupling relations between humans and cognitive artefacts, and subsequently in the responsible innovation of cognitive artefacts and human-artefact interfaces.

13.
Nutrients ; 10(8)2018 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-30072661

RESUMO

The consumption of alcohol and drugs of abuse among pregnant women has experienced a significant increase in the last decades. Suitable maternal nutritional status is crucial to maintain the optimal environment for fetal development but if consumption of alcohol or drugs of abuse disrupt the intake of nutrients, the potential teratogenic effects of these substances increase. Despite evidence of the importance of nutrition in addicted pregnant women, there is a lack of information on the effects of alcohol and drugs of abuse on maternal nutritional status; so, the focus of this review was to provide an overview on the nutritional status of addicted mothers and fetuses. Alcohol and drugs consumption can interfere with the absorption of nutrients, impairing the quality and quantity of proper nutrient and energy intake, resulting in malnutrition especially of micronutrients (vitamins, omega⁻3, folic acid, zinc, choline, iron, copper, selenium). When maternal nutritional status is compromised by alcohol and drugs of abuse the supply of essential nutrients are not available for the fetus; this can result in fetal abnormalities like Intrauterine Growth Restriction (IUGR) or Fetal Alcohol Spectrum Disorder (FASD). It is critical to find a strategy to reduce fetal physical and neurological impairment as a result of prenatal alcohol and drugs of abuse exposure combined with poor maternal nutrition. Prenatal nutrition interventions and target therapy are required that may reverse the development of such abnormalities.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Alcoolismo/fisiopatologia , Fenômenos Fisiológicos da Nutrição Materna , Estado Nutricional , Complicações na Gravidez/fisiopatologia , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/fisiopatologia , Alcoolismo/sangue , Alcoolismo/epidemiologia , Alcoolismo/terapia , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Humanos , Exposição Materna/efeitos adversos , Troca Materno-Fetal , Apoio Nutricional , Gravidez , Complicações na Gravidez/sangue , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/terapia , Fatores de Risco , Transtornos Relacionados ao Uso de Substâncias/sangue , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/terapia
14.
Nat Commun ; 9(1): 360, 2018 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-29367672

RESUMO

Induced pluripotent stem cells (iPSCs) have considerably impacted human developmental biology and regenerative medicine, notably because they circumvent the use of cells of embryonic origin and offer the potential to generate patient-specific pluripotent stem cells. However, conventional reprogramming protocols produce developmentally advanced, or primed, human iPSCs (hiPSCs), restricting their use to post-implantation human development modeling. Hence, there is a need for hiPSCs resembling preimplantation naive epiblast. Here, we develop a method to generate naive hiPSCs directly from somatic cells, using OKMS overexpression and specific culture conditions, further enabling parallel generation of their isogenic primed counterparts. We benchmark naive hiPSCs against human preimplantation epiblast and reveal remarkable concordance in their transcriptome, dependency on mitochondrial respiration and X-chromosome status. Collectively, our results are essential for the understanding of pluripotency regulation throughout preimplantation development and generate new opportunities for disease modeling and regenerative medicine.


Assuntos
Blastocisto/citologia , Células-Tronco Embrionárias/citologia , Camadas Germinativas/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Animais , Blastocisto/metabolismo , Células Cultivadas , Reprogramação Celular/genética , Técnicas de Reprogramação Celular , Desenvolvimento Embrionário/genética , Células-Tronco Embrionárias/metabolismo , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Camadas Germinativas/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Camundongos , Transcriptoma
15.
Hum Mutat ; 38(6): 615-620, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28256047

RESUMO

Alveolar capillary dysplasia with misalignment of pulmonary veins (ACDMPV) is a rare cause of pulmonary hypertension in newborns. Maternally inherited point mutations in Forkhead Box F1 gene (FOXF1), deletions of the gene, or its long-range enhancers on the maternal allele are responsible for this neonatal lethal disorder. Here, we describe monozygotic twins and one full-term newborn with ACD and gastrointestinal malformations caused by de novo mutations of FOXF1 on the maternal-inherited alleles. Since this parental transmission is consistent with genomic imprinting, the parent-of-origin specific monoallelic expression of genes, we have undertaken a detailed analysis of both allelic expression and DNA methylation. FOXF1 and its neighboring gene FENDRR were both biallelically expressed in a wide range of fetal tissues, including lung and intestine. Furthermore, detailed methylation screening within the 16q24.1 regions failed to identify regions of allelic methylation, suggesting that disrupted imprinting is not responsible for ACDMPV.


Assuntos
Fatores de Transcrição Forkhead/genética , Impressão Genômica , Síndrome da Persistência do Padrão de Circulação Fetal/genética , Alvéolos Pulmonares/anormalidades , Hibridização Genômica Comparativa , Metilação de DNA/genética , Feminino , Humanos , Hipertensão Pulmonar , Recém-Nascido , Herança Materna/genética , Mutação , Síndrome da Persistência do Padrão de Circulação Fetal/complicações , Síndrome da Persistência do Padrão de Circulação Fetal/patologia , Gravidez , Alvéolos Pulmonares/patologia , Gêmeos Monozigóticos
16.
Cell Stem Cell ; 20(1): 102-111, 2017 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-27989768

RESUMO

Sex chromosome dosage compensation is essential in most metazoans, but the developmental timing and underlying mechanisms vary significantly, even among placental mammals. Here we identify human-specific mechanisms regulating X chromosome activity in early embryonic development. Single-cell RNA sequencing and imaging revealed co-activation and accumulation of the long noncoding RNAs (lncRNAs) XACT and XIST on active X chromosomes in both early human pre-implantation embryos and naive human embryonic stem cells. In these contexts, the XIST RNA adopts an unusual, highly dispersed organization, which may explain why it does not trigger X chromosome inactivation at this stage. Functional studies in transgenic mouse cells show that XACT influences XIST accumulation in cis. Our findings therefore suggest a mechanism involving antagonistic activity of XIST and XACT in controlling X chromosome activity in early human embryos, and they highlight the contribution of rapidly evolving lncRNAs to species-specific developmental mechanisms.


Assuntos
Cromossomos Humanos X/genética , Desenvolvimento Embrionário/genética , RNA Longo não Codificante/genética , RNA não Traduzido/genética , Animais , Blastocisto/metabolismo , Bases de Dados como Assunto , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Camundongos , Células-Tronco Pluripotentes/metabolismo , RNA Longo não Codificante/metabolismo , RNA não Traduzido/metabolismo , Análise de Sequência de RNA , Análise de Célula Única , Transgenes
17.
Semin Cell Dev Biol ; 56: 48-57, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27174438

RESUMO

X-chromosome inactivation (XCI) in mammals represents an exceptional example of transcriptional co-regulation occurring at the level of an entire chromosome. XCI is considered as a means to compensate for gene dosage imbalance between sexes, yet the largest part of the chromosome is composed of repeated elements of different nature and origins. Here we consider XCI from a repeat point of view, interrogating the mechanisms for inactivating X chromosome-derived repeated sequences and discussing the contribution of repetitive elements to the silencing process itself and to its evolution.


Assuntos
Mamíferos/genética , Inativação do Cromossomo X/genética , Animais , Evolução Molecular , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Sequências Repetitivas de Ácido Nucleico/genética , Cromossomo X/genética
18.
Eur Heart J Cardiovasc Imaging ; 17(7): 804-11, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26392516

RESUMO

AIMS: The aim of this article was to determine whether lateral and septal early diastolic mitral annular velocities (LW-e' and IS-e', respectively) accuracy to reflect left ventricular (LV) relaxation is truly compromised by a limitation of mitral annular motion due to mitral annulus calcification (MAC) and to search for e' surrogates to circumvent this limitation. METHODS AND RESULTS: LW-e', IS-e', and peak early diastolic velocities at the basal-lateral and basal-septal LV segments 2 cm distal to the annulus (LW-e'2 and IS-e'2, respectively) were measured using tissue Doppler imaging (TDI) in 206 consecutive patients referred for echocardiography. Significant MAC (assessed by two-dimensional echocardiography) was present in 57 (28%) subjects. There was a significant reduction in LW-Δe' (LW-e' minus LW-e'2) in subjects with posterior MAC (0.15 ± 1.35 vs. 1.30 ± 1.24 cm/s, P < 0.0001) and a small but not significant reduction in IS-Δe' (IS-e' minus IS-e'2) in subjects with anterior MAC (-0.15 ± 1.04 vs. 0.42 ± 1.56 cm/s, P = 0.07), compared with age-matched no MAC subjects. Potential confusion factors were analysed on multiple regression. The basal segments in which e'2 were measured were free of calcification regardless of MAC. In search for e'2-based surrogates for e', the regression equation [Formula: see text] (R(2) = 0.86, P < 0.0001) was obtained from the first 100 consecutive subjects and validated in the next 49 no MAC subjects (intraclass correlation coefficient 0.96, P < 0.0001). In the septal side, no difference was found between IS-e' and IS-e'2 in the 149 subjects with no MAC (8.5 ± 3.1 vs. 8.5 ± 2.9 cm/s, P = 0.55). CONCLUSION: MAC significantly affected LW-e' (and not significantly IS-e') accuracy to reflect LV relaxation. [Formula: see text] and IS-e'2 as surrogates for LW-e' and IS-e', respectively, may correct this inaccuracy.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Calcinose/diagnóstico por imagem , Ecocardiografia Doppler de Pulso , Valva Mitral/diagnóstico por imagem , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Diástole/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/fisiopatologia , Contração Miocárdica/fisiologia , Prognóstico , Valores de Referência , Índice de Gravidade de Doença
19.
Cell Rep ; 4(6): 1156-67, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-24055057

RESUMO

The equalization of pericentric heterochromatin from distinct parental origins following fertilization is essential for genome function and development. The recent implication of noncoding transcripts in this process raises questions regarding the connection between RNA and the nuclear organization of distinct chromatin environments. Our study addresses the interrelationship between replication and transcription of the two parental pericentric heterochromatin (PHC) domains and their reorganization during early embryonic development. We demonstrate that the replication of PHC is dispensable for its clustering at the late two-cell stage. In contrast, using parthenogenetic embryos, we show that pericentric transcripts are essential for this reorganization independent of the chromatin marks associated with the PHC domains. Finally, our discovery that only reverse pericentric transcripts are required for both the nuclear reorganization of PHC and development beyond the two-cell stage challenges current views on heterochromatin organization.


Assuntos
Desenvolvimento Embrionário/genética , Heterocromatina/genética , Animais , Modelos Animais de Doenças , Feminino , Genoma , Humanos , Masculino , Camundongos
20.
Pediatr. catalan ; 71(4): 149-152, oct.-dic. 2011. ilus
Artigo em Espanhol | IBECS | ID: ibc-99703

RESUMO

Introducción. Son bien conocidos los efectos deletéreos directamente asociados a la intoxicación etílica aguda, así como su asociación con factores comórbidos como son el consumo simultáneo de otras sustancias tóxicas o los traumatismos graves. Observación clínica. Adolescente de 17 años traída a urgencias por intoxicación etílica aguda que es dada de alta tras recuperación íntegra. Reconsulta a las 24 horas del alta por cefalea intensa que, junto con el hallazgo de un hemotímpano izquierdo en la exploración física, hace sospechar la presencia de una lesión intracraneal que se confirma mediante neuroimagen. Comentarios. La dificultad que supone realizar una adecuada anamnesis por el estado del paciente con una intoxicación etílica aguda y la amnesia que ocasiona el etanol a partir de determinadas concentraciones en sangre facilitan que pasen desapercibidas lesiones internas en una primera valoración. El caso presentado trata de poner de manifiesto como la exploración física sistemática es uno de los pilares básicos en el examen clínico del paciente intoxicado por etanol, permitiendo dirigir la petición de pruebas complementarias que habitualmente son poco necesarias en el manejo de la mayoría de los casos (AU)


Introduction. The deleterious effects directly associated with acute ethylic intoxication are well-known, as well as their association with comorbid factors such us simultaneous consumption of other toxic substances or to serious traumatism. Clinical observation. 17-year-old teenager who presented with acute ethylic intoxication to Emergency Department was discharged after complete recovery. She re-consulted 12 hours later with severe headache. In her physical exploration was detected a left hemotympanum. A traumatic brain injury was suspected and it was confirmed by neuroimage. Comments. The physical conditions of patients with acute ethylic intoxication and the amnesia caused by certain blood ethanol concentrations make anamnesis difficult and it’s easy that some internal injuries been unnoticed in the first evaluation. The case presented tries to reveal that a physical systematic exploration is one of the basis in the clinical examination of the patient intoxicated by ethanol, allowing to assess if there are complementary tests required, which does not happen in most of the cases (AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Intoxicação Alcoólica/complicações , Intoxicação Alcoólica/epidemiologia , Ferimentos e Lesões/complicações , Cefaleia/complicações , Neuroimagem/métodos , Traumatismos Cranianos Penetrantes/complicações , Emergências/epidemiologia , Intoxicação Alcoólica/prevenção & controle , Hemorragias Intracranianas/complicações , Neuroimagem/tendências , Neuroimagem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...