A New Mouse Model for Marfan Syndrome Presents Phenotypic Variability Associated with the Genetic Background and Overall Levels of Fbn1 Expression

Marfan syndrome is an autosomal dominant disease of connective tissue caused by mutations in the fibrillin-1 encoding gene FBN1. Patients present cardiovascular, ocular and skeletal manifestations, and although being fully penetrant, MFS is characterized by a wide clinical variability both within and between families. Here we describe a new mouse model of MFS that recapitulates the clinical heterogeneity of the syndrome in humans. Heterozygotes for the mutant Fbn1 allele mgΔloxPneo, carrying the same internal deletion of exons 19–24 as the mgΔ mouse model, present defective microfibrillar deposition, emphysema, deterioration of aortic wall and kyphosis. However, the onset of a clinical phenotypes is earlier in the 129/Sv than in C57BL/6 background, indicating the existence of genetic modifiers of MFS between these two mouse strains. In addition, we characterized a wide clinical variability within the 129/Sv congenic heterozygotes, suggesting involvement of epigenetic factors in disease severity. Finally, we show a strong negative correlation between overall levels of Fbn1 expression and the severity of the phenotypes, corroborating the suggested protective role of normal fibrillin-1 in MFS pathogenesis, and supporting the development of therapies based on increasing Fbn1 expression

Sperm Oxidative Stress Is Detrimental to Embryo Development: A Dose-Dependent Study Model and a New and More Sensitive Oxidative Status Evaluation

Our study aimed to assess the impact of sperm oxidative stress on embryo development by means of a dose-dependent model. In experiment 1, straws from five bulls were subjected to incubation with increasing H2O2 doses (0, 12.5, 25, and 50 μM). Motility parameters were evaluated by Computed Assisted System Analysis (CASA). Experiment 2 was designed to study a high (50 μM) and low dose (12.5 μM) of H2O2 compared to a control (0 μM). Samples were incubated and further used for in vitro fertilization. Analyses of motility (CASA), oxidative status (CellROX green and 2’-7’ dichlorofluorescein diacetate), mitochondrial potential (JC-1), chromatin integrity (AO), and sperm capacitation status (chlortetracycline) were performed. Embryos were evaluated based on fast cleavage (30 h.p.i.), cleavage (D=3), development (D=5), and blastocyst rates (D=8). We observed a dose-dependent deleterious effect of H2O2 on motility and increase on the percentages of positive cells for CellROX green, capacitated sperm, and AO. A decrease on cleavage and blastocyst rates was observed as H2O2 increased. Also, we detected a blockage on embryo development. We concluded that sperm when exposed to oxidative environment presents impaired motility traits, prooxidative status, and premature capacitation; such alterations resulting in embryo development fail

Sperm Oxidative Stress Is Detrimental to Embryo Development: A Dose-Dependent Study Model and a New and More Sensitive Oxidative Status Evaluation

Our study aimed to assess the impact of sperm oxidative stress on embryo development by means of a dose-dependent model. In experiment 1, straws from five bulls were subjected to incubation with increasing H 2 O 2 doses (0, 12.5, 25, and 50 M). Motility parameters were evaluated by Computed Assisted System Analysis (CASA). Experiment 2 was designed to study a high (50 M) and low dose (12.5 M) of H 2 O 2 compared to a control (0 M). Samples were incubated and further used for in vitro fertilization. Analyses of motility (CASA), oxidative status (CellROX green and 2'-7' dichlorofluorescein diacetate), mitochondrial potential (JC-1), chromatin integrity (AO), and sperm capacitation status (chlortetracycline) were performed. Embryos were evaluated based on fast cleavage (30 h.p.i.), cleavage ( = 3), development ( = 5), and blastocyst rates ( = 8). We observed a dose-dependent deleterious effect of H 2 O 2 on motility and increase on the percentages of positive cells for CellROX green, capacitated sperm, and AO. A decrease on cleavage and blastocyst rates was observed as H 2 O 2 increased. Also, we detected a blockage on embryo development. We concluded that sperm when exposed to oxidative environment presents impaired motility traits, prooxidative status, and premature capacitation; such alterations resulting in embryo development fail

Bovine gene polymorphisms related to fat deposition and meat tenderness

Leptin, thyroglobulin and diacylglycerol O-acyltransferase play important roles in fat metabolism. Fat deposition has an influence on meat quality and consumers' choice. The aim of this study was to determine allele and genotype frequencies of polymorphisms of the bovine genes, which encode leptin (LEP), thyroglobulin (TG) and diacylglycerol O-acyltransferase (DGAT1). A further objective was to establish the effects of these polymorphisms on meat characteristics. We genotyped 147 animals belonging to the Nelore (Bos indicus), Canchim (5/8 Bos taurus + 3/8 Bos indicus), Rubia Gallega X Nelore (1/2 Bos taurus + 1/2 Bos indicus), Brangus Three-way cross (9/16 Bos taurus + 7/16 Bos indicus) and Braunvieh Three-way cross (3/4 Bos taurus + 1/4 Bos indicus) breeds. Backfat thickness, total lipids, marbling score, ribeye area and shear force were fitted, using the General Linear Model (GLM) procedure of the SAS software. The least square means of genotypes and genetic groups were compared using Tukey's test. Allele frequencies vary among the genetic groups, depending on Bos indicus versus Bos taurus influence. The LEP polymorphism segregates in pure Bos indicus Nelore animals, which is a new finding. The T allele of TG is fixed in Nelore, and DGAT1 segregates in all groups, but the frequency of allele A is lower in Nelore animals. The results showed no association between the genotypes and traits studied, but a genetic group effect on these traits was found. So, the genetic background remains relevant for fat deposition and meat tenderness, but the gene markers developed for Bos taurus may be insufficient for Bos indicus

Triagem realizada por enfermeiros no serviço de urgência pediátrica : fatores que influenciam a satisfação dos pais

Contexto: A triagem nos serviços de urgência (SU) é uma função essencial e complexa, tratando-se de um processo baseado na tomada de decisão clínica do enfermeiro. A perceção e satisfação associada aos cuidados ali prestados representam um importante indicador de qualidade. A investigação acerca da satisfação relacionada com triagem realizada por enfermeiros num serviço de urgência pediátrica ainda tem espaço para exploração e discussão de outros dados, em realidades diferentes. Objetivos: Identificar os conhecimentos referidos pelos pais sobre o processo de triagem da criança no SU pediátrica; descrever as competências que os pais reconhecem como importantes no enfermeiro que executa o processo de triagem no SU pediátrico; reconhecer os fatores que interferem na satisfação dos pais enquanto utilizadores do SU pediátrica, relativamente à triagem realizada pelo enfermeiro; refletir sobre a influência do processo de triagem realizado pelo enfermeiro na satisfação dos pais utilizadores do SU pediátrica. Métodos: Trata-se de um estudo não experimental, tipo exploratório-descritivo, com colheita de dados através de entrevistas semiestruturadas e gravação em áudio. Resultados: Os pais demonstraram ter um défice de conhecimentos em aspetos relacionados com o processo de triagem. Os pais reconhecem várias capacidades, incluídas nas competências clínicas, psicossociais e pessoais, ao enfermeiro que executa a triagem. Os fatores influenciadores referidos foram, de forma positiva, a segurança/confiança transmitida, a atitude afetiva/acolhedora, rapidez no atendimento e a presença constante do enfermeiro; e de forma negativa, a atitude de indiferença para com a situação, o tempo despendido com a triagem, a prioridade considerada injusta e a interrupção da triagem por motivos não relacionados com o caso. Não se verificou concertação relativamente à satisfação com a triagem como fator influenciador da satisfação com o SU. Conclusões: Os resultados evidenciam aspetos fundamentais que afetam a satisfação dos pais e mostram que as competências reconhecidos pelos pais, estão de acordo com as competências do enfermeiro da triagem e interligadas com o perfil de competências específicas do enfermeiro especialista em enfermagem de saúde infantil e pediatria.ABSTRACT Context: Triage in the emergency department (ED) is an essential and complex function; a process based on the clinical decision-making of the nurse. The perception and satisfaction associated with the care provided, represent an important quality indicator. The satisfaction related to the role of the triage nurse in a pediatric ED is a research field that can be further explored using data generated in different contexts. Objectives: To identify the parent’s knowledge about the triage process, the competences that they recognize in the triage nurse and the factors that affect their satisfaction as users of the pediatric ED. To assess the parent’s satisfaction with the triage role and how it influences the satisfaction with the ED. Methods: It is a non-experimental, exploratory-descriptive study, with data collected using semi-structured interviews and audio recording. Results: Parents have shown a lack of knowledge in aspects related to the triage role. Parents recognize several skills, including clinical, psychosocial and personal skills, to the triage nurse. The affecting factors referred were, in a positive way, the security/confidence transmitted, the affective/welcoming attitude, speed in the admission process and the constant presence of the nurse; and in a negative way, the attitude of indifference towards the situation, the time spent with the triage, the priority considered to be unfair and the interruption of the triage role for reasons unrelated to the case. There was no consensus regarding satisfaction with triage as an influencing factor for satisfaction with the ED. Conclusions: The results highlight fundamental aspects that affect parent’s satisfaction and show that, the skills and the factors recognized by the parents are related to the skills of the triage nurse and interconnected with the skills profile of the specialist nurse in child health and pediatrics

Targetting of <i>Fbn1</i>.

<p>(A) Scheme of <i>Fbn1</i> targeting. From top to bottom, fibrillin1 protein with the internally deleted region (residues 770–1042); schematic representation of the corresponding <i>Fbn1</i> gene region with the probes (I and III) used in the Southern-blot analysis, and the sizes of BamHI (b) and HindIII (h) fragments; and targeted <i>Fbn1</i>^mgΔloxPneo allele with the neoR flanked by lox-P sequences (triangles). (B) Southern blot of genomic DNA from correctly targeted ES clone digested with BamHI, and hybridized to probe I. (C) sequence of the cDNA from the <i>Fbn1</i>^mgΔloxPneo allele showing the junction of exons 18 and 25; (D) Heredogram of founder heterozygotes in a mixed 129/Sv/CD-1 background. Hetreozygotes were phenotypically normal until the F3, where one severely affected heterozygote was found (arrow), whose X-ray is shown. (E) Relative quantification of total <i>Fbn1</i> mRNA levels in wild-type (WT), heterozygous (HE) and homozygous (HO) fetal fibroblasts by Real Time RT-PCR analysis (P<0.05).</p

Phenotypic variability within the 129/Sv strain.

<p>(A) Comparison of histological slides and radiography of 129/Sv heterozygotes at 3 months of age show phenotypic variation in this strain. Wild-type (+/+), asymptomatic (AS) and severely affected (SE) heterozygous mice. (B) Average mean linear intercept at 3 and 6 months of age (*P<0.42, **P<0.0006, ***P<0.006). (C) Average thickness of thoracic aortic media at 3 and 6 months of age (*P<0.33, **P<0.04, †P<0.8, ††P<0.01). (D) Average KR at 3 and 6 months (*P<0.03, **P<0.04). (MI) Mildly affected animals. The number of animals analyzed in each group (n) and the ages (3 m and 6 m represent 3 months and 6 months, respectively) are shown.</p

Immunofluorescence of cultured fetal fibroblasts.

<p>(A) Wild-type, (B) heterozygous and (C) homozygous fibroblasts immune-stained for fibrillin-1 (scale bars 50 µm). In contrast to the elaborate network of immunoreactive fibrillin-1 seen in control lines, heterozygous and homozygous cell cultures show a diffuse pattern of immunoreactive material. (D) Representative field at higher magnification to show intracellular deposition of mutant protein (scale bar 25 µm).</p