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1.
Artigo em Inglês | MEDLINE | ID: mdl-38082865

RESUMO

This study focuses on the robustness of a generic Finite Element Model (FEM) of Percutaneous Transluminal Angioplasty (PTA) procedure with permanent set. The influence of three different parameters on simulation robustness were investigated: the stenosis percent, the stenosis offset and the arterial caliber. Five arterial calibers are modeled by adapting the ratio between the inner diameter and the wall thickness. Overall, forty configurations were tested with the same simulation settings and boundary conditions. Results shows convergence issues caused by excessive deformations of elements for stenosis above 65% blockage. Moreover, an increasing stenosis offset tends to decrease convergence. Simulation of PTA on small calibers and large calibers are less robust than intermediate e.g., iliac calibers.Clinical Relevance- PTA can benefit from numerical tools to improve the procedure outcomes. A FEM simulation of PTA without stent deployment can predict the permanent strain induced by this surgery for various configurations. However, robustness of the simulation is required to consider its transfer to clinics. This work aims to determine the robustness boundaries of an implicit solver for PTA simulation. It shows that an implicit solver is robust for all artery calibers with a stenosis below 50% blockage. Moreover medium-caliber arteries exhibit better robustness with converging solutions for stenosis reaching 60% blockage.


Assuntos
Angioplastia , Stents , Humanos , Resultado do Tratamento , Constrição Patológica , Angioplastia/métodos , Artérias
2.
NanoImpact ; 29: 100446, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36503111

RESUMO

This work investigates the aerosols emitted from carbon fibre-reinforced epoxy composites (CFC) incorporating nanomaterials (nanoclays and nanotubes), subjected to simultaneous fire and impact, representing an aeroplane or automotive crash. Simultaneous fire and impact tests were performed using a previously described bespoke testing methodology with the capability to collect particles released from the front/back faces of the impacted composites plus the effluents. In this work the methodology has been further developed by connecting the Dekati Low Pressure Impactor (DLPI) and Mini Particle Sampler (MPS) sampling system in the extraction chimney. The aerosols emitted have been characterized using various devices devoted to the analysis of aerosols. The influence of the nanoadditives in the matrix on the number concentration and the size distribution of airborne particles produced, was studied with a cascade impactor in the 5 nm-10 µm range. The morphology of the separated soot fractions was examined by SEM. The measurement of aerodynamic size of particles that can deposit in human respiratory tract indicate that 75% of the soot and particles released from CFC could deposit in the lungs reaching the bronchi region at a minimum. There was however, a minimal difference between the number particle concentrations or particle-size mass distribution of particles from CFC and CFC containing nanoadditives. Moreover, no fibres were found in the effluents.


Assuntos
Poluentes Ocupacionais do Ar , Nanoestruturas , Humanos , Poluentes Ocupacionais do Ar/análise , Partículas e Gotas Aerossolizadas , Fibra de Carbono/análise , Tamanho da Partícula , Fuligem/análise , Aerossóis/análise , Pulmão/química
3.
Eur Ann Otorhinolaryngol Head Neck Dis ; 139(1): 21-27, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34140263

RESUMO

OBJECTIVES: This document presents the fundamentals of speech audiometry in noise, general requirements for implementation and criteria for choice among the tests available in French according to the health-professional's needs. MATERIAL AND METHODS: The recommendations are based on a systematic analysis of the literature carried out by a multidisciplinary group of doctors, audiologists and audioprosthetists from all over France. They are graded A, B, C or expert opinion according to decreasing level of scientific evidence. RESULTS: Eight tests of speech audiometry in noise can be used in France. CONCLUSION: To be complete, evaluation of hearing status requires testing understanding of speech in noise. The examination must begin with a minimum of two measurements familiarizing the subject with the test procedure. For initial diagnosis, adaptive procedures establishing the 50% speech reception threshold (SRT50) in noise are to be preferred in order to obtain a rapid and standardized measurement of perception of speech in noise. When the aim is to measure real-life speech comprehension, tests based on sentences, cocktail-party noise and free-field stimulation are to be preferred. Prosthetic gain is evaluated exclusively in free field. This is the only way to evaluate the contribution of binaurality and to measure perception in noise in an environment as close as possible to real life. In order to avoid acoustic interference in free field, at least five loudspeakers should be used, in particular for evaluating the effectiveness of directional microphones, CROS devices enabling sounds picked up in the damaged ear to be rerouted to the functional ear, or bimodal fitting (i.e., when hearing is enabled by two modalities: for example, hearing aid for one ear, cochlear implant for the other).


Assuntos
Audiologia , Implantes Cocleares , Auxiliares de Audição , Otolaringologia , Percepção da Fala , Adulto , Humanos , Fala
5.
Moulineaux; European Annals of Otorhinolaryngology, Head and Neck Diseases; Jun. 14, 2021.
Não convencional em Inglês | BIGG - guias GRADE | ID: biblio-1291637

RESUMO

This document presents the fundamentals of speech audiometry in noise, general requirements for implementation and criteria for choice among the tests available in French according to the health-professional's needs. The recommendations are based on a systematic analysis of the literature carried out by a multidisciplinary group of doctors, audiologists and audioprosthetists from all over France. They are graded A, B, C or expert opinion according to decreasing level of scientific evidence. Eight tests of speech audiometry in noise can be used in France. To be complete, evaluation of hearing status requires testing understanding of speech in noise. The examination must begin with a minimum of two measurements familiarizing the subject with the test procedure. For initial diagnosis, adaptive procedures establishing the 50% speech reception threshold (SRT50) in noise are to be preferred in order to obtain a rapid and standardized measurement of perception of speech in noise. When the aim is to measure real-life speech comprehension, tests based on sentences, cocktail-party noise and free-field stimulation are to be preferred. Prosthetic gain is evaluated exclusively in free field. This is the only way to evaluate the contribution of binaurality and to measure perception in noise in an environment as close as possible to real life. In order to avoid acoustic interference in free field, at least five loudspeakers should be used, in particular for evaluating the effectiveness of directional microphones, CROS devices enabling sounds picked up in the damaged ear to be rerouted to the functional ear, or bimodal fitting (i.e., when hearing is enabled by two modalities: for example, hearing aid for one ear, cochlear implant for the other).


Assuntos
Humanos , Audiometria da Fala/métodos , Perda Auditiva/diagnóstico , França
6.
Int J Pediatr Otorhinolaryngol ; 141: 110557, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33341717

RESUMO

Enlarged vestibular aqueduct (EVA) is a common finding in tomodensitometry. When cranial MRI is performed, enlarged endolymphatic sac (EES) can also be found. Profound hearing loss is a common finding in these patients but a few studies have investigated vestibular function after cochlear implantation (CI) in EVA and EES patients. Our main objective was to find out whether in EVA children candidates to CI, a higher endolymphatic sac (ES) volume was predictive for higher rates of postsurgical vestibular complications. METHODS: We retrospectively included EVA children who benefited from CI, during the last 2 years. Two groups were constituted according to the presence or not of a vestibular impairment (decrease in the VOR gain on the VHIT test on one of the semicircular canals and/or a loss of cVEMPs) 6 months after CI. Endolymphatic volume of both VA and ES was measured for each patient. RESULTS: Fifteen patients were included. The mean endolymph volume was significantly higher in the impaired group (0.40 cm3 ± 0.23, range 0.08-0.70) than in the non-impaired group (0.11 cm3 ± 0.07, range 0.04-0.29; p = 0.029). Four children of the impaired group were followed during one year. At the end of vestibular rehabilitation, all children recovered a lateral canal function and a saccular function. CONCLUSION: In EVA children, a combined EES appears to increase the risk of severe post CI vestibular impairment. To minimize this risk prior CI surgery, besides tomodensitometry, MRI measurement of the ES volume should be systematically performed.


Assuntos
Implante Coclear , Saco Endolinfático , Perda Auditiva Neurossensorial , Aqueduto Vestibular , Criança , Saco Endolinfático/diagnóstico por imagem , Saco Endolinfático/cirurgia , Humanos , Estudos Retrospectivos , Aqueduto Vestibular/anormalidades , Aqueduto Vestibular/diagnóstico por imagem , Aqueduto Vestibular/cirurgia
7.
J Hazard Mater ; 371: 415-422, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-30875568

RESUMO

At the end of their life cycle, it is expected that many industrial silicone components end up in incineration waste plants. Hence, the issue concerning the risks resulting from the generation of fumes (combustion gas and aerosol) has to be addressed. The aim of our work was to investigate the behavior and fate of nanosilicas from filled polydimethylsiloxane nanocomposites burnt under two different scenarios of incineration. Combustion tests have been performed at lab-scale using a particular tubular furnace and a specific cone calorimeter. The collected fumes (particulate matter and gas phase) have been characterized using various techniques. The results show persistent nanosilica particles, newly produced nanosilica particles in the fumes and in the residues, as well as silicon oxycarbide SixOyCz particles which seem to originate from polysiloxane matrix decomposition.

8.
J Hazard Mater ; 365: 405-412, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30448553

RESUMO

The number of products containing nanomaterials is increasing this last ten years. Information and literature about the end-of-life of nanocomposites often remains partial and does not address the overall fate and transformations of nanoparticles that may affect biological responses. This paper underlines that the physico-chemical features of nanoparticles can be modified by the incineration process and the available toxicological data on pristine nanofillers might not be relevant to assess the modified nanoparticles included in soot. Combustion tests have been performed at lab-scale using a cone calorimeter modified to collect fumes (particulate matter and gas phase) and have been characterized using various techniques. Nanocomposites selected were poly(ethylene vinyl acetate) containing Al-based nanoparticles, i.e. boehmites or alumina. Evaluations of in vitro cytotoxicity responses on pristine nanofillers, soot and residual ash, show that safe boehmite nanoparticles, become toxic due to a chemical modification after incineration process.


Assuntos
Hidróxido de Alumínio , Óxido de Alumínio , Nanoestruturas , Polivinil , Alumínio , Hidróxido de Alumínio/química , Hidróxido de Alumínio/toxicidade , Óxido de Alumínio/química , Óxido de Alumínio/toxicidade , Animais , Incineração , Camundongos , Nanoestruturas/química , Nanoestruturas/toxicidade , Polivinil/química , Polivinil/toxicidade , Células RAW 264.7 , Fuligem/análise
9.
J Hazard Mater ; 301: 153-62, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26348148

RESUMO

This work investigates the aerosols emitted during combustion of aircraft and naval structural composite materials (epoxy resin/carbon fibers and vinyl ester/glass fibers and carbon nanotubes). Combustion tests were performed at lab-scale using a modified cone calorimeter. The aerosols emitted have been characterized using various metrological devices devoted to the analysis of aerosols. The influence of the nature of polymer matrices, the incorporation of fibers and carbon nanotubes as well as glass reinforcements on the number concentration and the size distribution of airborne particles produced, was studied in the 5 nm-10 µm range. Incorporation of carbon fibers into epoxy resin significantly reduced the total particle number concentration. In addition, the interlaced orientation of carbon fibers limited the particles production compared to the composites with unidirectional one. The carbon nanotubes loading in vinyl ester resin composites influenced the total particles production during the flaming combustion with changes during kinetics emission. Predominant populations of airborne particles generated during combustion of all tested composites were characterized by a PN50 following by PN(100-500).

10.
Environ Sci Technol ; 49(9): 5450-7, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25760854

RESUMO

Nanoclay-based nanocomposites have been widely studied and produced since the late 1990s, and frequently end up in waste disposal plants. This work investigates the behavior of PA6/HNTs nanocomposites (nylon-6 incorporating halloysite nanotubes) during incineration. Incineration tests were performed at lab-scale using a specific tubular furnace modified in order to control the key incineration parameters within both the combustion and postcombustion zones. The combustion residues and combustion aerosol (particulate matter and gas phase) collected downstream of the incinerator furnace were characterized using various aerosol analysis techniques. Time tracking of the gas and particle-number concentrations revealed two-step char formation during combustion. HNTs transformed into other mineral structures which were found in both the aerosol and the residues. During combustion of the polymer, it appears that HNTs contribute to the formation of a cohesive char layer that protects the residual material.


Assuntos
Silicatos de Alumínio/química , Incineração , Nanotubos/química , Caprolactama/análogos & derivados , Caprolactama/química , Argila , Nanocompostos/química , Polímeros/química
12.
J Physiol Pharmacol ; 65(5): 623-31, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25371521

RESUMO

The use of glutathione (GSH) and sulfate for the detoxification of paracetamol (acetaminophen, APAP) could occur at the expense of the physiological uses of cysteine (Cys). Indeed GSH and sulfate both originate from Cys. Significant APAP-induced Cys loss could generate alterations in GSH and protein metabolisms leading to muscle wasting. The study aimed to investigate the effects of chronic treatment with APAP on whole-body and tissue homeostasis (mass, GSH, proteins, and nitrogen balance) in relation to sulfur losses through APAP-detoxification pathways. Adult male Wistar rats were fed 0% APAP, 0.5% APAP or 1% APAP diets for 17 days. APAP doses were respectively around and largely above the threshold of sulfation saturation for rats. During the last days, the rats were placed in metabolic cages in order to quantify N balance and urinary APAP metabolites. Gastrocnemius muscle mass, protein and GSH contents, N balance and plasma free cyst(e)ine were 8% (P=0.02), 7% (P=0.03), 26% (P=0.01), 37% (P=0.01), and 33% (P=0.003) lower in the 1% APAP group than in the 0% APAP group, respectively. There was no significant difference in these parameters between the 0.5% APAP group and the 0% APAP group. Muscle wasting occurred when the detoxification of APAP through the GSH-dependent pathway was highly activated. Muscle protein synthesis could have been reduced due to a shortage in Cys and/or an increase in protein degradation in response to intra-muscular oxidative stress. Hence, without dietary sulphur amino acid increase, peripheral bioavailability of Cys and muscle GSH are potential players in the control of muscle mass under chronic treatment with APAP, an analgesic medication of widespread use, especially in the elderly.


Assuntos
Acetaminofen/efeitos adversos , Analgésicos não Narcóticos/efeitos adversos , Glutationa/metabolismo , Músculo Esquelético/efeitos dos fármacos , Atrofia Muscular/induzido quimicamente , Acetaminofen/farmacocinética , Acetaminofen/urina , Alanina Transaminase/sangue , Analgésicos não Narcóticos/farmacocinética , Analgésicos não Narcóticos/urina , Animais , Aspartato Aminotransferases/sangue , Cisteína/sangue , Fezes/química , Masculino , Proteínas Musculares/metabolismo , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Nitrogênio/metabolismo , Ratos Wistar
13.
J Dairy Sci ; 97(9): 5497-507, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24997663

RESUMO

We analyzed embryo culture medium (CM) and recipient blood plasma using Fourier transform infrared (FTIR) metabolomics to predict pregnancy outcome. Individually cultured, in vitro-produced (IVP) blastocysts were transferred to recipients as fresh and vitrified-warmed. Spent CM and plasma samples were evaluated using FTIR. The discrimination capability of the classifiers was assessed for accuracy, sensitivity (pregnancy), specificity (nonpregnancy), and area under the receiver operator characteristic curve (AUC). Within all IVP fresh embryos (birth rate=52%), high AUC were obtained at birth, especially with expanded blastocysts (CM: 0.80±0.053; plasma: 0.89±0.034). The AUC of vitrified IVP embryos (birth rate = 31%) were 0.607±0.038 (CM, expanded blastocysts) and 0.672±0.023 (plasma, all stages). Recipient plasma generally predicted pregnancy outcome better than did embryo CM. Embryos and recipients with improved pregnancy viability were identified, which could increase the economic benefit to the breeding industry.


Assuntos
Transferência Embrionária/veterinária , Fertilização In Vitro/veterinária , Resultado da Gravidez/veterinária , Prenhez , Espectroscopia de Infravermelho com Transformada de Fourier , Animais , Blastocisto/citologia , Blastocisto/metabolismo , Bovinos , Criopreservação/métodos , Meios de Cultura , Feminino , Metabolômica , Modelos Biológicos , Plasma , Gravidez
14.
Rev Med Suisse ; 10(423): 691-2, 694-5, 2014 Mar 26.
Artigo em Francês | MEDLINE | ID: mdl-24783735

RESUMO

In the word obesity, a clinical concept of chronic systemic disease pairs up with pejorative individual or social representations. Being obese is also facing situations of disability, organ failure, uncertainty of the fate and stigmatization. A care concept inspired by rehabilitation and therapeutic patient education could offer a new way and other purposes to the treatment of obesity. Restoring functions, learning how to adapt and change their environment, obese people may live better today, out of their isolation and develop partners in their projects of life and health. Rehabilitation of an obese patient is much more than weight loss!


Assuntos
Obesidade/reabilitação , Educação de Pacientes como Assunto , Redução de Peso , Índice de Massa Corporal , Doença Crônica , Humanos , Obesidade/psicologia , Estereotipagem
16.
Physiol Genomics ; 46(2): 39-56, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24220328

RESUMO

We analyzed the change in gene expression related to dam physiological status in day (D)18 embryos from growing heifers (GH), early lactating cows (ELC), and late lactating cows (LLC). Dam energy metabolism was characterized by measurement of circulating concentrations of insulin, glucose, IGF-1, nonesterified fatty acids, ß-hydroxybutyrate, and urea before embryo flush. The metabolic parameters were related to differential gene expression in the extraembryonic tissues by correlation analysis. Embryo development estimated by measuring the length of the conceptuses and the proportion of expected D18 gastrulating stages was not different between the three groups of females. However, embryo metabolism was greatly affected by dam physiological status when we compared GH with ELC and GH with LLC but to a lesser extent when ELC was compared with LLC. Genes involved in glucose, pyruvate, and acetate utilization were upregulated in GH vs. ELC conceptuses (e.g., SLC2A1, PC, ACSS2, ACSS3). This was also true for the pentose pathway ( PGD, TKT), which is involved in synthesis of ribose precursors of RNA and DNA. The pathways involved in lipid synthesis were also upregulated in GH vs. ELC. Despite similar morphological development, the molecular characteristics of the heifers' embryos were consistently different from those of the cows. Most of these differences were strongly related to metabolic/hormone patterns before insemination and during conceptus free-life. Many biosynthetic pathways appeared to be more active in heifer embryos than in cow embryos, and consequently they seemed to be healthier, and this may be more conducive to continue development.


Assuntos
Embrião de Mamíferos/metabolismo , Metabolismo Energético/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Metabolismo dos Lipídeos/fisiologia , Fenômenos Reprodutivos Fisiológicos , Ácido 3-Hidroxibutírico/sangue , Animais , Glicemia/metabolismo , Peso Corporal/fisiologia , Bovinos , Análise por Conglomerados , Embrião de Mamíferos/embriologia , Ácidos Graxos não Esterificados/sangue , Feminino , Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Lactação/fisiologia , Masculino , Leite/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Ureia/sangue
17.
Reprod Fertil Dev ; 26(1): 12-21, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24305173

RESUMO

Genomic tools are now available for most livestock species and are used routinely for genomic selection (GS) in cattle. One of the most important developments resulting from the introduction of genomic testing for dairy cattle is the application of reasonably priced low-density single nucleotide polymorphism technology in the selection of females. In this context, combining genome testing and reproductive biotechnologies in young heifers enables new strategies to generate replacement and elite females in a given period of time. Moreover, multiple markers have been detected in biopsies of preimplantation stage embryos, thus paving the way to develop new strategies based on preimplantation diagnosis and the genetic screening of embryos. Based on recent advances in GS, the present review focuses on new possibilities inherent in reproductive technologies used for commercial purposes and in genetic schemes, possible side effects and beneficial impacts on reproductive efficiency. A particular focus is on the different steps allowing embryo genotyping, including embryo micromanipulation, DNA production and quality assessment.


Assuntos
Cruzamento , Indústria de Laticínios , Fertilidade/genética , Genômica , Reprodução/genética , Técnicas de Reprodução Assistida/veterinária , Animais , Bovinos , Técnicas de Cultura Embrionária/veterinária , Feminino , Genótipo , Hereditariedade , Masculino , Linhagem , Fenótipo , Gravidez , Diagnóstico Pré-Implantação/veterinária
18.
Rev Med Suisse ; 9(373): 369-70, 372-3, 2013 Feb 13.
Artigo em Francês | MEDLINE | ID: mdl-23477070

RESUMO

Androgen deprivation is a therapeutic option for patients with prostate cancer, however with a range of side effects that negatively affects their physical and psychological condition. A multidisciplinary care program, ADAPP ("Androgenic deprivation in prostate cancer patients"), has been created with a special focus on managing these side effects. This article describes the intervention of the liaison psychiatry within this program, with care options ranging from psychological support to intensive psychotherapy to address patients' intrapsychic dynamics throughout this care program. Clinical cases are reported to illustrate the relevance and the necessity of this specialized counselling.


Assuntos
Antagonistas de Androgênios/administração & dosagem , Aconselhamento , Equipe de Assistência ao Paciente , Neoplasias da Próstata/terapia , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Androgênios/efeitos adversos , Aconselhamento/métodos , Depressão/induzido quimicamente , Depressão/prevenção & controle , Disfunção Erétil/induzido quimicamente , Disfunção Erétil/prevenção & controle , Fadiga/induzido quimicamente , Fadiga/prevenção & controle , Humanos , Comunicação Interdisciplinar , Libido/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Osteoporose/induzido quimicamente , Osteoporose/prevenção & controle , Neoplasias da Próstata/tratamento farmacológico , Psicoterapia , Distúrbios do Início e da Manutenção do Sono/induzido quimicamente , Distúrbios do Início e da Manutenção do Sono/prevenção & controle , Resultado do Tratamento
19.
Hum Reprod ; 28(2): 430-41, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23202989

RESUMO

STUDY QUESTION: Does BCAR4 have a role in mammalian embryo development? SUMMARY ANSWER: Expression, localization and functional data support that BCAR4 is a maternal-effect protein in non-rodent mammals. WHAT IS KNOWN ALREADY: BCAR4 was previously identified as an oocyte-specific gene in cattle, and as a marker of certain breast tumors in humans. STUDY DESIGN, SIZE, DURATION: Human oocytes were obtained from patients undergoing IVF, but had failed to mature after ovarian stimulation. Dog oocytes were obtained from ovariectomized bitches. Pig, horse and bovine ovaries were obtained from commercial slaughterhouses for extraction of immature oocyte-cumulus complexes. In vivo matured bovine matured oocytes were obtained after ovulation induction and ovulation inducing treatment of Montbeliard heifers. MATERIALS, SETTING AND METHODS: Expression at the RNA level was analyzed by reverse transcription coupled to polymerase chain reaction. Western blot and immunolabeling coupled to confocal or electronic microscopy were used to analyze bovine protein expression and intracellular localization. For the functional approach, short-interfering RNA were microinjected into mature bovine oocytes, followed by IVF; cleavage and embryo development were recorded. MAIN RESULTS AND THE ROLE OF CHANCE: The BCAR4 gene is conserved in mammalian species from various orders and has been lost in rodents after divergence with lagomorphs. The transcript is expressed in the oocytes of humans and domestic species. We bring the first experimental evidence of the BCAR4 protein in mammals. In cattle, the protein is not detected in immature oocytes but starts to be synthesized during maturation, increases in the zygote and persists until the morula stage. The protein is detected throughout the cytoplasm in mature oocytes, concentrates in and around the pronuclei in the zygote, and appears to shuttle in and out of the nuclei starting in the 2-cell embryo; BCAR4 is also present at the junctions between blastomeres from 2-cell to morula. In our functional approach, targeting the BCAR4 transcript by small-interfering RNA significantly compromised development to the morula or/and blastocyst stages (P < 0.05, logistic regression). LIMITATIONS, REASONS FOR CAUTION: As indicated above, protein expression and function were investigated in cattle and mostly in vitro matured oocytes were used. WIDER IMPLICATIONS OF THE FINDINGS: This study provides a novel candidate gene whose mutation or deregulation may underlie certain cases of unexplained female infertility.


Assuntos
Desenvolvimento Embrionário/genética , Oócitos/metabolismo , RNA Longo não Codificante/metabolismo , Sequência de Aminoácidos , Animais , Bovinos , Sequência Conservada , Cães , Cavalos , Humanos , Modelos Logísticos , Dados de Sequência Molecular , RNA Longo não Codificante/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Coelhos , Alinhamento de Sequência , Análise de Sequência , Suínos
20.
Theriogenology ; 78(6): 1294-302, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22898026

RESUMO

This study evaluates a new synthetic substitute (CRYO3, Ref. 5617, Stem Alpha, France) for animal-based products in bovine embryo cryopreservation solutions. During the experiment, fetal calf serum (FCS) and bovine serum albumin (BSA) were used as references. A combination of a thermodynamic approach using differential scanning calorimetry and a biological approach using in vitro-produced bovine embryo slow-freezing was used to characterize cryopreservation solutions containing CRYO3, FCS and BSA. The CRYO3 and fetal calf serum (FCS) slow-freezing solutions were made from Dulbecco's phosphate-buffered saline containing 1.5 m ethylene glycol, 0.1 m sucrose and 20% (v.v(-1)) of CRYO3 or FCS. The bovine serum albumin (BSA) solution was made by adding 0.1 m sucrose to a commercial solution containing 1.5 m ethylene glycol and 4 g L(-1) BSA. These solutions were evaluated using three characteristics: the end of melting temperature, the enthalpy of crystallization (thermodynamic approach) and the embryo survival and hatching rates after in vitro culture (biological approach). The CRYO3 and FCS solutions had similar thermodynamic properties. In contrast, the thermodynamic characteristics of the BSA solution were different from those of the FCS and CRYO3 solutions. Nevertheless, the embryo survival and hatching rates obtained with the BSA and FCS solutions were not different. Similar biological properties can thus be obtained with slow freezing solutions that have different physical properties within a defined range. The embryo survival rate after 48 h of in vitro culture obtained with the CRYO3 solution (81.5%) was higher than that obtained with the BSA (42.2%, P = 0.000 12) and FCS solutions (58%, P = 0.016). Similarly, the embryo hatching rate after 72 h of in vitro culture was higher with the CRYO3 solution (61.1%) than with the BSA (31.1%, P = 0.0055) and FCS solutions (36%, P = 0.018). We conclude that CRYO3 can be used as a chemically defined substitute for animal-based products in in vitro-produced bovine embryo cryopreservation solutions.


Assuntos
Bovinos/embriologia , Criopreservação/veterinária , Crioprotetores , Fertilização In Vitro/veterinária , Soluções , Animais , Blastocisto/fisiologia , Varredura Diferencial de Calorimetria/veterinária , Criopreservação/métodos , Técnicas de Cultura Embrionária/veterinária , Sangue Fetal , Soroalbumina Bovina , Termodinâmica
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