47 research outputs found
Fragile X syndrome: intergenerational allele instability and associated phenotypes in families
Fragile X syndrome (FXS) is the most common hereditary form of intellectual disability with an estimated frequency of 1/4000 males and 1/8000 females. This disease is caused by a (CGG)n expansion in the 5’UTR of the FMR1 gene, which as a result is methylated and gene silenced. Four classes of alleles can be found based on CGG repeat length: normal (5-44), intermediate (45-54), premutation (55-200) and full mutation (>200). In premutation carriers, both FMR1-related primary ovarian insufficiency (FXPOI) and fragile-X associated tremor/ataxia syndrome (FXTAS) have been described. To gain insights into instability of FMR1 CGG repeats and associated phenotypes, we studied 541 individuals from 128 FXS Portuguese families.
DNA samples were genotyped by PCR and Southern blot analysis. Additional clinical evaluation was performed in premutation carriers.
Among FXS families, 5.3% intermediate, 29.9% premutation and 26.6% full mutation alleles were found. Normal and intermediate alleles were stable upon transmission. For 115 maternal premutation transmissions, 26 (23%) with alleles ranging 60-98 CGGs remained in premutation size with an average expansion of 17 repeat units, whereas 89 (77%) with alleles ranging from 66-199 CGGs expanded to full mutation. In 44 transmissions of maternal full mutation, the offspring inherited alleles in the full mutation range. For 10 paternal transmissions of premutations, ranging 56-120 CGGs, all daughters inherited a premutation allele, with an average expansion of 7 repeat units. After clinical evaluation of 7 premutation carriers, 1 male with FXTAS and 2 females with FXPOI were identified; however the remaining premutation individuals were not yet examined.
In Portuguese FXS families, allele instability upon transmission is in agreement with previous reports. The risk of premutation to full mutation expansion increases with maternal premutation size.FCT Fundação para a Ciência e a Tecnologi
Virgin and recycled polypropylene composites reinforced with sisal by-product
Foram estudadas as propriedades térmicas e mecânicas de compósitos de polipropileno, virgem e reciclado, reforçados com 30% em massa de fibras residuais de sisal, assim como o perfil de processamento e a morfologia da matriz polimérica. Para tanto, foram determinadas a resistência à tração, o módulo de Young, alongamento na ruptura, e energia de impacto. As amostras também foram caracterizadas por MEV, DMTA e TG. Para ambos os compósitos de polipropileno, virgem e reciclado, com a adição das fibras, o alongamento na ruptura mostrou uma queda significativa, enquanto que a resistência à tração não sofreu grandes variações. Houve um aumento significativo nos valores de tração na ruptura e de energia de impacto com a adição das fibras de sisal na matriz de polipropileno. As análises térmicas mostraram ligações secundárias, como as ligações polares, entre as fibras e a matriz, concordando com o comportamento mecânico dos compósitos. Constatou-se que a temperatura de transição vítrea não variou após a adição da fibra.The mechanical and thermal properties of virgin and recycled polypropylene composites reinforced with 30% by mass of residual sisal fibers were studied, in addition to an analysis of the extrusion process and morphology of the polymeric matrix. Tensile strength, Young's modulus, elongation at break, and impact energy were determined. The samples were also characterized by SEM, DMTA and TG analyses. Elongation at break of the composites presented a significant decrease, while the tensile strength was not affected significantly by addition of sisal fibers. A significant increase was observed in the tension of rupture and in the impact energy of the composite reinforced with sisal fiber. The thermal analyses indicated secondary interactions, such as polar interactions, between the fibers and the matrix, consistent with the mechanical behavior of the composites. The glass transition temperature has not changed after fiber addition.Universidade Federal de São Carlos - Departamento de Engenharia de MateriaisFinepCNP
FXTAS is rare among Portuguese patients with movement disorders: FMR1 premutations may be associated with a wider spectrum of phenotypes
The fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder caused by expansions of 55-200 CGG repeats in the 5'UTR of the FMR1 gene. These FMR1 premutation expansions have relatively high frequency in the general population. To estimate the frequency of FMR1 premutations among Portuguese males with non-familial, late-onset movement disorders of unknown etiology, we assessed CGG repeat size in males with disease onset after the age of 50 and negative or unknown family history for late-onset movement disorders, who were sent for SCA, HD, or PD genetic testing at a reference laboratory. The selected patients had a primary clinical diagnosis based on one of the following cardinal features of FXTAS: ataxia, tremor, or cognitive decline. A total of 86 subjects were genotyped for the CGG repeat in the FMR1 gene. We detected one patient with an expansion in the premutation range. The frequency of FMR1 premutations was 1.9% (1/54) in our group of patients with ataxia as the primary clinical feature, and 1.2% (1/86) in the larger movement disorders group. In the family of the FXTAS case, premutation-transmitting females presented a history of psychiatric symptoms, suggesting that, given the wide phenotypical expression of the premutation in females, neuropsychiatric surveillance is necessary. In conclusion, genetic testing for FXTAS should be made available to patients with adult-onset movement disorders to enable adequate genetic counseling to family members
O PAPEL DO MÉDICO VETERINÁRIO NOS PROJETOS DE CONSERVAÇÃO DE ANIMAIS SILVESTRES AMEAÇADOS DE EXTINÇÃO
Introdução: Animais silvestres são vítimas das ações antrópicas inconsequentes, por isso inúmeras espécies estão ameaçadas de extinção. Dentre essas ações estão as queimadas, o tráfico de animais silvestres e a introdução de animais exóticos. Por conseguinte, impactos são gerados, como a mudança desordenada no nicho ecológico que resulta na morte e gera traumas em diversos animais. Visto isso, projetos de conservação são necessários para minimizar esses danos, assim contam com o importante papel dos médicos veterinários, fundamentais para a realização da triagem, da reabilitação e da educação ambiental. Objetivos: Discutir sobre as principais causas e impactos da extinção de animais silvestres bem como a atuação do médico veterinário. Metodologia: O estudo foi realizado por meio de revisão literária de forma exploratória e qualitativa, buscando fontes em artigos científicos, teses e revistas, e site da internet como Scielo e Google acadêmico. Considerações Finais: Este trabalho possibilita o maior entendimento de questões relacionadas ao Médico Veterinário e seu importante papel na preservação de animais silvestres em risco de extinção. Em uma época em que cada vez menos se dá valor à vida animal, é de suma importância que tenhamos profissionais que saibam de fato lutar contra esse tipo de crime, e defendam a vida e os direitos dos animais. Como abordado no 1° capítulo, as queimadas são uma das principais causas de danos à fauna e flora, colocando em risco inúmeras espécies já ameaçadas. No 2° capítulo abordamos a existência de um órgão que destaca as espécies que estão em extinção, seja por caça, taxidermia, ou outras atividades ilegais. No 3° capítulo discutimos e abordamos o papel e os deveres do Médico Veterinário em relação a animais em extinção. Conclusão: Portanto conclui-se que, o médico veterinário é excepcional para que os animais não sejam extintos. Principalmente devido à educação ambiental que esse realiza, visto que os maiores causadores desse problema são as ações antrópicas. Então, o educar conscientizará a população e impedirá que mais espécies sejam extintas e todas continuarão com sua importância ecológica
Diagnóstico genético pré-implantacional (PGD) e a sua aplicação na reprodução humana / Preimplantational genetic diagnosis (PGD) and its application in human reproduction
Um dos grandes avanços da medicina reprodutiva dos últimos anos é o Diagnóstico Genético Pré-Implantacional (PGD), essa é uma técnica que nos permite conhecer aspectos da composição genética do embrião antes da sua implantação, usando tecnologias da reprodução humana assistida. Ela se divide em duas categorias que vão evidenciar objetivos e protocolos diversos: O PGD para doenças monogênicas (PGT-M), e o (PGT-A) para detectar as alterações cromossômicas no cariótipo. Diante da importância da técnica, objetiva-se apresentar os benefícios do PGD para a reprodução humana e seus aspectos éticos. Por meio dos conhecimentos disponíveis, fez-se uma revisão de literatura com intenção de explorar o diagnóstico genético pré-implantacional empregado na reprodução humana. Durante a escolha dos procedimentos de fertilização in vitro, primeiro é descoberto o que impossibilita o casal de gestar um filho, só então é estudado e analisado as melhores técnicas para tentar minimizar as chances de falhas no procedimento. Com o desenvolvimento de novas técnicas envolvidas no PGD, futuramente os avanços dos estudos irão permitir o diagnóstico de uma gama de alterações genéticas ainda na fase embrionária
Complete blood count parameters as biomarkers of retinopathy of prematurity: a Portuguese multicenter study
© The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.Purpose: To evaluate complete blood count (CBC) parameters in the first week of life as predictive biomarkers for the development of retinopathy of prematurity (ROP).
Methods: Multicenter, prospective, observational study of a cohort of preterm infants born with gestational age (GA) < 32 weeks or birth weight < 1500 g in eight Portuguese neonatal intensive care units. All demographic, clinical, and laboratory data from the first week of life were collected. Univariate logistic regression was used to assess risk factors for ROP and then multivariate regression was performed.
Results: A total of 455 infants were included in the study. The median GA was 29.6 weeks, and the median birth weight was 1295 g. One hundred and seventy-two infants (37.8%) developed ROP. Median values of erythrocytes (p < 0.001), hemoglobin (p < 0.001), hematocrit (p < 0.001), mean corpuscular hemoglobin concentration (p < 0.001), lymphocytes (p = 0.035), and platelets (p = 0.003) of the group of infants diagnosed with ROP any stage were lower than those without ROP. Mean corpuscular volume (MCV) (p = 0.044), red blood cell distribution width (RDW) (p < 0.001), erythroblasts (p < 0.001), neutrophils (p = 0.030), neutrophils-lymphocytes ratio (p = 0.028), and basophils (p = 0.003) were higher in the ROP group. Higher values of MCV, erythroblasts, and basophils remained significantly associated with ROP after multivariate regression.
Conclusion: In our cohort, the increase in erythroblasts, MCV, and basophils in the first week of life was significantly and independently associated with the development of ROP. These CBC parameters may be early predictive biomarkers for ROP.Open access funding provided by FCT|FCCN (b-on). This work was supported by the Laboratório de Genética and the Instituto de Saúde Ambiental (ISAMB) of the Faculdade de Medicina of Universidade de Lisboa and the Instituto de Investigação Científica Bento da Rocha Cabral. The writing of the manuscript was also supported by funds from Fundação para a Ciência e a Tecnologia to ISAMB (ref. UIDB/04295/2020 and UIDP/04295/2020). This work was also part of a doctoral project funding by the company CUF with a PhD grant in Medicine awarded in 2021 and by the Portuguese Society of Ophthalmology with a PhD grant awarded in 2019.info:eu-repo/semantics/publishedVersio
Complete blood count parameters as biomarkers of retinopathy of prematurity: a Portuguese multicenter study
Purpose: To evaluate complete blood count (CBC) parameters in the first week of life as predictive biomarkers for the development of retinopathy of prematurity (ROP).
Methods: Multicenter, prospective, observational study of a cohort of preterm infants born with gestational age (GA) < 32 weeks or birth weight < 1500 g in eight Portuguese neonatal intensive care units. All demographic, clinical, and laboratory data from the first week of life were collected. Univariate logistic regression was used to assess risk factors for ROP and then multivariate regression was performed.
Results: A total of 455 infants were included in the study. The median GA was 29.6 weeks, and the median birth weight was 1295 g. One hundred and seventy-two infants (37.8%) developed ROP. Median values of erythrocytes (p < 0.001), hemoglobin (p < 0.001), hematocrit (p < 0.001), mean corpuscular hemoglobin concentration (p < 0.001), lymphocytes (p = 0.035), and platelets (p = 0.003) of the group of infants diagnosed with ROP any stage were lower than those without ROP. Mean corpuscular volume (MCV) (p = 0.044), red blood cell distribution width (RDW) (p < 0.001), erythroblasts (p < 0.001), neutrophils (p = 0.030), neutrophils-lymphocytes ratio (p = 0.028), and basophils (p = 0.003) were higher in the ROP group. Higher values of MCV, erythroblasts, and basophils remained significantly associated with ROP after multivariate regression.
Conclusion: In our cohort, the increase in erythroblasts, MCV, and basophils in the first week of life was significantly and independently associated with the development of ROP. These CBC parameters may be early predictive biomarkers for ROP.info:eu-repo/semantics/publishedVersio