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1.
J Assist Reprod Genet ; 39(4): 801-816, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35301622

RESUMO

Epigenetics is the branch of genetics that studies the different mechanisms that influence gene expression without direct modification of the DNA sequence. An ever-increasing amount of evidence suggests that such regulatory processes may play a pivotal role both in the initiation of pregnancy and in the later processes of embryonic and fetal development, thus determining long-term effects even in adult life. In this narrative review, we summarize the current knowledge on the role of epigenetics in pregnancy, from its most studied and well-known mechanisms to the new frontiers of epigenetic regulation, such as the role of ncRNAs and the effects of the gestational environment on fetal brain development. Epigenetic mechanisms in pregnancy are a dynamic phenomenon that responds both to maternal-fetal and environmental factors, which can influence and modify the embryo-fetal development during the various gestational phases. Therefore, we also recapitulate the effects of the most notable environmental factors that can affect pregnancy and prenatal development, such as maternal nutrition, stress hormones, microbiome, and teratogens, focusing on their ability to cause epigenetic modifications in the gestational environment and ultimately in the fetus. Despite the promising advancements in the knowledge of epigenetics in pregnancy, more experience and data on this topic are still needed. A better understanding of epigenetic regulation in pregnancy could in fact prove valuable towards a better management of both physiological pregnancies and assisted reproduction treatments, other than allowing to better comprehend the origin of multifactorial pathological conditions such as neurodevelopmental disorders.


Assuntos
Epigênese Genética , Desenvolvimento Fetal , Adulto , DNA/metabolismo , Epigênese Genética/genética , Feminino , Desenvolvimento Fetal/genética , Feto/metabolismo , Humanos , Gravidez
4.
J Neurogenet ; 28(1-2): 86-97, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24564792

RESUMO

The molecular mechanisms of action of antipsychotic drugs (APDs) are not fully understood. Here, we characterize phenotypes of missense and knockout mutations in the Caenorhabditis elegans transient receptor potential melastatin (TRPM) channel ortholog gtl-2, a candidate APD target identified in a genome-wide RNAi (RNA interference) screen for Suppressors of Clozapine-induced Larval Arrest (scla genes). We then employ the developmental phenotypes of gtl-2(lf) mutants to validate our previous gtl-2(RNAi) result. GTL-2 acts in the excretory canal cell to regulate Mg(2+) homeostasis. Using exc (excretory canal abnormal) gene mutants, we demonstrate that excretory canal cell function is necessary for clozapine-induced developmental delay and lethality. Moreover, cell-specific promoter-driven expression studies reveal that GTL-2 function in the excretory canal cell is important for its role in the SCLA phenotype. We then investigate the mechanism by which GTL-2 function in the excretory canal cell impacts clozapine-induced phenotypes. gtl-2(lf) mutations cause hypermagnesemia, and we show that exposure of the wild-type strain to high Mg(2+) phenocopies gtl-2(lf) with respect to suppression of clozapine-induced developmental delay and lethality. Our results suggest that GTL-2 TRPM channel function in the excretory canal cell is important for clozapine's developmental effects. TRP channels are expressed in mammalian brain and are implicated in the pathogenesis of mental illnesses but have not been previously implicated in APD action.


Assuntos
Antipsicóticos/farmacologia , Proteínas de Caenorhabditis elegans/genética , Clozapina/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Fenótipo , Canais de Cátion TRPM/genética , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/metabolismo , Relação Dose-Resposta a Droga , Ovos , Regulação da Expressão Gênica no Desenvolvimento/genética , Larva/citologia , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Magnésio/metabolismo , Sulfato de Magnésio/farmacologia , Mutação/genética , Neurônios/efeitos dos fármacos , Músculos Faríngeos/efeitos dos fármacos , Músculos Faríngeos/fisiologia , Interferência de RNA/fisiologia , Canais de Cátion TRPM/deficiência
5.
J Chem Phys ; 138(12): 12A527, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23556778

RESUMO

The dramatic slowdown of the structural relaxation at the glass transition is one of the most puzzling features of glass dynamics. Single molecule orientational correlation times show this strong Vogel-Fulcher-Tammann temperature dependence typical for glasses. Through statistical analysis of single molecule trajectories, we can identify individual glass rearrangement events in the vicinity of a probe molecule in the glass former poly(vinyl acetate) from 8 K below to 6 K above the glass transition temperature. We find that changes in the distribution of waiting times between individual glass rearrangement events are much less dramatic with temperature, the main difference being a small, but decisive number of increasingly long waiting times at lower temperatures. We notice similar individual, local relaxation events in molecular dynamics trajectories for a variety of glassy systems further from the glass transition, leading to waiting time distributions with similar features as those observed in the single molecule experiments. We show that these rare long waiting times are responsible for the dramatic increase in correlation time upon cooling.

6.
Open Res Eur ; 2: 60, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37645336

RESUMO

Background: This paper presents part of a wider research project called TRESCA[1] which aims to develop trust in science through the innovation of communication practices. Connected with the topic of trust in sciences, in terms of the credibility and reliability of scientific information, a part of the project was dedicated to the assessment of the explanatory power of two main elements of communication: audio and video. Particular attention was given to how these two elements relate to the perception of citizens, mediating with the latent imaginaries, emotional charges and value judgements that are the basis of the framing of relevant news, and thus with the ability of people to distinguish between correct and false communication. Methods: To investigate these aspects, an ad hoc workshop was designed and implemented in three European countries with the aim of understanding how people interpret the content of a scientific communication video with particular attention to the role of images and audio. Some probe questions were carefully selected to explore content and latent imaginaries, emotional and critical aspects also related with the trust of the communication. Results: By involving citizens in discussions and innovation efforts, many suggestions and recommendations have been collected. In today's everyday life, where the visual is very widespread, thanks to the ever-growing presence of social media, the power of images can exceed that of audio. Conclusions: Since watching a video without sound can mislead the real content of the message, especially when the source or the speaker aren't recognisable. This can have many repercussions on people's ability to evaluate the truthfulness of a news and, consequently, on the choice to grant trust - or distrust.

7.
Audiol Res ; 11(4): 582-593, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34698053

RESUMO

Since the early 2000s, an ever-increasing subset of missense pathogenic variants in the ACTG1 gene has been associated with an autosomal-dominant, progressive, typically post-lingual non-syndromic hearing loss (NSHL) condition designed as DFNA20/26. ACTG1 gene encodes gamma actin, the predominant actin protein in the cytoskeleton of auditory hair cells; its normal expression and function are essential for the stereocilia maintenance. Different gain-of-function pathogenic variants of ACTG1 have been associated with two major phenotypes: DFNA20/26 and Baraitser-Winter syndrome, a multiple congenital anomaly disorder. Here, we report a novel ACTG1 variant [c.625G>A (p. Val209Met)] in an adult patient with moderate-severe NSHL characterized by a downsloping audiogram. The patient, who had a clinical history of slowly progressive NSHL and tinnitus, was referred to our laboratory for the analysis of a large panel of NSHL-associated genes by next generation sequencing. An extensive review of previously reported ACTG1 variants and their associated phenotypes was also performed.

8.
PLoS One ; 15(4): e0231334, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32275736

RESUMO

Subthreshold stochastic vestibular stimulation (SVS) is thought to enhance vestibular sensitivity and improve balance. However, it is unclear how SVS affects standing and walking when balance is challenged, particularly when the eyes are open. It is also unclear how different methods to determine stimulation intensity influence the effects. We aimed to determine (1) whether SVS affects stability when balance is challenged during eyes-open standing and overground walking tasks, and (2) how the effects differ based on whether optimal stimulation amplitude is derived from sinusoidal or cutaneous threshold techniques. Thirteen healthy adults performed balance-unchallenged and balance-challenged standing and walking tasks with SVS (0-30 Hz zero-mean, white noise electrical stimulus) or sham stimulation. For the balance-challenged condition, participants had inflatable rubber hemispheres attached to the bottom of their shoes to reduce the control provided by moving the center of pressure under their base of support. In different blocks of trials, we set SVS intensity to either 50% of participants' sinusoidal (motion) threshold or 80% of participants' cutaneous threshold. SVS reduced medial-lateral trunk velocity root mean square in the balance-challenged (p < 0.05) but not in the balance-unchallenged condition during standing. Regardless of condition, SVS decreased step-width variability and marginally increased gait speed when walking with the eyes open (p < 0.05). SVS intensity had minimal effect on the standing and walking measures. Taken together, our results provide insight into the effectiveness of SVS at improving balance-challenged, eyes-open standing and walking performance in healthy adults.


Assuntos
Marcha , Equilíbrio Postural , Vestíbulo do Labirinto/fisiologia , Adulto , Feminino , Humanos , Masculino , Modelos Neurológicos , Postura , Limiar Sensorial , Processos Estocásticos , Potenciais Evocados Miogênicos Vestibulares
9.
Public Underst Sci ; 25(6): 737-53, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-25904600

RESUMO

Public engagement is considered a crucial process in the transition towards sustainable energy systems. However, less space has been devoted to understand how policy makers and stakeholders view citizens and their relationship with energy issues. Nonetheless, together with technological advancements, policies and political debates on energy affect public engagement as well as individual practices. This article aims at tackling this issue by exploring how policy makers and stakeholders have socially constructed sustainable energy in Italian parliamentary debates and consultations during recent years (2009-2012). Results show that societal discourses on sustainable energy are oriented in a manner that precludes public engagement. The political debate is characterised by argumentative 'short-circuits' that constrain individual and community actions to the acceptance or the refusal of top-down decisions and that leave little room for community empowerment and bottom-up innovation.


Assuntos
Participação da Comunidade , Política Ambiental/legislação & jurisprudência , Governo Federal , Energia Renovável/legislação & jurisprudência , Itália , Política
10.
Acta Biomed ; 87(3): 282-285, 2016 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-28112695

RESUMO

In order to increase knowledge on the morphology and structure of the articular disc of the TMJ for a better understanding of the functional role of the same, it proceeded with an investigation on histological samples in the block of 'TMJ and periarticular tissues of adult rabbits and human fetuses at different stage of development.


Assuntos
Articulação Temporomandibular/anatomia & histologia , Animais , Idade Gestacional , Humanos , Coelhos , Articulação Temporomandibular/embriologia
11.
Ann N Y Acad Sci ; 1161: 554-61, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19426348

RESUMO

Fluids with a unique surface tension behavior, the so-called "self-rewetting fluids," are considered to be promising working fluids not only in reduced-gravity environments but also in terrestrial applications. Ultralightweight polyimide-based wickless heat pipe panels with flexible, inflatable, and deployable functions were fabricated using self-rewetting fluids. Fundamental operation tests of these panels were conducted under conditions of reduced gravity during parabolic flight. We obtained promising experimental results on the thermal performance of the panels in reduced gravity, although the experimental conditions were not entirely satisfactory.

12.
Psicol. pesq ; 8(2): 179-188, dez. 2014. ilus, tab
Artigo em Português | LILACS | ID: lil-781294

RESUMO

As representações sociais do envelhecimento podem ser diferentes de acordo com a cultura. O objetivo deste estudo foi comparar as representações do envelhecimento no Brasil e na Itália. Participaram 360 sujeitos distribuídos igualmente entre as nacionalidades, sexo e grupo etário. O questionário apresentou questões fechadas e abertas. Os resultados indicam associação das variáveis sociais (sexo, grupo etário e contexto cultural) com duas representações de envelhecimento: uma, na qual as relações sociais e a atividade completam a ideia de um momento exitoso, em que experiência de vida produziu sabedoria diante da vida, e outra como um processo que, embora traga experiência e sabedoria, resulta em declínio, doenças, inatividade e incapacidades, indicando o fim da vida.


The social representations of aging may differ according to culture. The aim of this study was to compare the representations of aging in Brazil and in Italy. The participants were 360 subjects equally distributed between nationalities, sex and age group. The questionnaire presented closed and open ended questions. The results indicate the association of social variables (sex, age group and cultural context) with two representations of aging: one, where social relations and activity complete the idea of a successful moment in which life experience produced wisdom toward life, and another as a process that, although bring experience and wisdom, results in decline, illness, inactivity and incapacity, indicating the end of life.


Assuntos
Humanos , Masculino , Feminino , Idoso , Envelhecimento
13.
Psicol. pesq ; 8(2): 179-188, dez. 2014. ilus, tab
Artigo em Português | Index Psi (psicologia) | ID: psi-67449

RESUMO

As representações sociais do envelhecimento podem ser diferentes de acordo com a cultura. O objetivo deste estudo foi comparar as representações do envelhecimento no Brasil e na Itália. Participaram 360 sujeitos distribuídos igualmente entre as nacionalidades, sexo e grupo etário. O questionário apresentou questões fechadas e abertas. Os resultados indicam associação das variáveis sociais (sexo, grupo etário e contexto cultural) com duas representações de envelhecimento: uma, na qual as relações sociais e a atividade completam a ideia de um momento exitoso, em que experiência de vida produziu sabedoria diante da vida, e outra como um processo que, embora traga experiência e sabedoria, resulta em declínio, doenças, inatividade e incapacidades, indicando o fim da vida.(AU).


The social representations of aging may differ according to culture. The aim of this study was to compare the representations of aging in Brazil and in Italy. The participants were 360 subjects equally distributed between nationalities, sex and age group. The questionnaire presented closed and open ended questions. The results indicate the association of social variables (sex, age group and cultural context) with two representations of aging: one, where social relations and activity complete the idea of a successful moment in which life experience produced wisdom toward life, and another as a process that, although bring experience and wisdom, results in decline, illness, inactivity and incapacity, indicating the end of life.(AU)


Assuntos
Humanos , Masculino , Feminino , Idoso , Envelhecimento
14.
Acta Crystallogr D Biol Crystallogr ; 58(Pt 10 Pt 1): 1628-32, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12351875

RESUMO

This paper reports experimental results and modelling on the crystallisation processes induced by counter diffusion method of a precipitant agent in a lysozyme protein solution. Comparison between experimental observations and numerical simulations in the presence of convection and sedimentation and without them (suppressed using gel) provides a validation of the model. Different values of the initial protein concentration are used, in order to investigate the effects of supersaturation conditions on the process, and in particular on nucleation. The model and the experimental approach may represent a useful methodology for the determination of the parameters and conditions that may lead to protein crystallisation. A Mach-Zehnder interferometer is used to monitor the transport dynamics in situ in the fluid phase by observing the compositional field. The effect of the solute transport gives rise to a "nucleation front" that propagates inside the protein solution. The crystal formation, caused by progressing of the front, results in a modulation in time and in space (similar to Liesegang patterns), due to the non-linear interplay among transport, crystal nucleation and growth. Both experimental observation and numerical modelling show spatial and size distributions of crystals that demonstrate comparable evidences of the phenomena.


Assuntos
Cristalização/métodos , Animais , Precipitação Química , Cristalização/estatística & dados numéricos , Difusão , Interferometria , Modelos Químicos , Muramidase/química , Soluções
15.
Acta Crystallogr D Biol Crystallogr ; 59(Pt 4): 773-6, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12657808

RESUMO

(PPG)(10) crystallization experiments onboard the ISS using the Advanced Protein Crystallization Facility have shown parallel and coherent crystal motions. The residual acceleration profiles and the History of the ISS Increment 3 mission allow a quantitative interpretation of these motions. Two events determine the observed crystal motions: the undocking of the Space Shuttle and a change in the ISS attitude required for power generation. No correlation between these motions and the crystal quality is apparent.


Assuntos
Colágeno/química , Peptídeos/química , Voo Espacial , Ausência de Peso , Cristalização , Sefarose
16.
Acta Crystallogr D Biol Crystallogr ; 58(Pt 10 Pt 1): 1690-4, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12351887

RESUMO

Single chains of the collagen model polypeptide with sequence (Pro-Pro-Gly)(10), hereafter referred to as (PPG)(10), aggregate to form rod-shaped triple helices. Crystals of (PPG)(10) were grown in the Advanced Protein Crystallization Facility (APCF) both onboard the International Space Station (ISS) and on Earth. The experiments allow the direct comparison of four different crystallization environments for the first time: solution in microgravity ((g), agarose gel in (g, solution on earth, and gel on earth. Both on board and on ground, the crystal growth was monitored by a CCD video camera. The image analysis provided information on the spatial distribution of the crystals, their movement and their growth rate. The analysis of the distribution of crystals reveals that the crystallization process occurs as it does in batch conditions. Slow motions have been observed onboard the ISS. Different to Space-Shuttle experiment, the crystals onboard the ISS moved coherently and followed parallel trajectories. Growth rate and induction time are very similar both in gel and in solution, suggesting that the crystal growth rate is controlled by the kinetics at the interface under the used experimental conditions. These results provide the first data in the crystallogenesis of (PPG)(10), which is a representative member of non-globular, rod-like proteins.


Assuntos
Colágeno/química , Cristalização/métodos , Peptídeos/química , Géis , Sefarose , Soluções , Voo Espacial , Fatores de Tempo , Gravação em Vídeo , Ausência de Peso
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