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1.
J Colloid Interface Sci ; 663: 73-81, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38394819

RESUMEN

Electroactive materials are increasingly being used in strategies to regenerate cardiac tissue. These materials, particularly those with electrical conductivity, are used to actively recreate the electromechanical nature of the cardiac tissue. In the present work, we describe a novel combination of poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)), a highly electroactive polymer, with graphene (G), exhibiting high electrical conductivity. G/P(VDF-TrFE) films have been characterized in terms of topographical, physico-chemical, mechanical, electrical, and thermal properties, and studied the response of cardiomyocytes adhering to them. The results indicate that the crystallinity and the wettability of the composites remain almost unaffected after G incorporation. In turn, surface roughness, Young modulus, and electric properties are higher in G/P(VDF-TrFE). Finally, the composites are highly biocompatible and able to support cardiomyocyte adhesion and proliferation, particularly surface treated ones, demonstrating the suitability of these materials for cardiac tissue engineering applications.


Asunto(s)
Polímeros de Fluorocarbono , Grafito , Hidrocarburos Fluorados , Polivinilos , Compuestos de Vinilo , Ingeniería de Tejidos , Corazón
2.
J Mater Chem B ; 10(34): 6472-6482, 2022 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-35968772

RESUMEN

Cardiac tissue regeneration strategies are increasingly taking advantage of electroactive scaffolds to actively recreate the tissue microenvironment. In this context, this work reports on advanced materials based on two different ionic liquids (ILs), 2-hydroxyethyl-trimethylammonium dihydrogen phosphate ([Ch][DHP]) and choline bis(trifluoromethylsulfonyl)imide ([Ch][TFSI]), combined with poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) for the development of ionic electroactive IL/polymer hybrid materials for cardiac tissue engineering (TE). The morphological, physico-chemical, thermal and electrical properties of the hybrid materials, as well as their potential use as scaffolds for cardiac TE applications, were evaluated. Besides inducing changes in surface topography, roughness and wettability of the composites, the incorporation of [Ch][DHP] and [Ch][TFSI] leads to the increase in surface (σsurface) and volume (σvolume) electrical conductivities. Furthermore, washing the hybrid samples with phosphate-buffered saline solution strongly decreases the σsurface, whereas σsurface and σvolume of the composites remain almost unaltered after exposure to ultraviolet sterilization treatment. Additionally, it is verified that the incorporation of IL influences the P(VDF-TrFE) microstructure and crystallization process, acting as a defect during its crystallization. Cytotoxicity assays revealed that hybrid films based on [Ch][DHP] alone are not cytotoxic. These films also support H9c2 myoblast cell adhesion and proliferation, demonstrating their suitability for cardiac TE strategies based on electroactive microenvironments.


Asunto(s)
Líquidos Iónicos , Ingeniería de Tejidos , Conductividad Eléctrica , Líquidos Iónicos/química , Fosfatos , Polímeros
3.
Eur J Hum Genet ; 27(5): 747-759, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30664714

RESUMEN

CYFIP2, encoding the evolutionary highly conserved cytoplasmic FMRP interacting protein 2, has previously been proposed as a candidate gene for intellectual disability and autism because of its important role linking FMRP-dependent transcription regulation and actin polymerization via the WAVE regulatory complex (WRC). Recently, de novo variants affecting the amino acid p.Arg87 of CYFIP2 were reported in four individuals with epileptic encephalopathy. We here report 12 independent patients harboring a variety of de novo variants in CYFIP2 broadening the molecular and clinical spectrum of a novel CYFIP2-related neurodevelopmental disorder. Using trio whole-exome or -genome sequencing, we identified 12 independent patients carrying a total of eight distinct de novo variants in CYFIP2 with a shared phenotype of intellectual disability, seizures, and muscular hypotonia. We detected seven different missense variants, of which two occurred recurrently (p.(Arg87Cys) and p.(Ile664Met)), and a splice donor variant in the last intron for which we showed exon skipping in the transcript. The latter is expected to escape nonsense-mediated mRNA decay resulting in a truncated protein. Despite the large spacing in the primary structure, the variants spatially cluster in the tertiary structure and are all predicted to weaken the interaction with WAVE1 or NCKAP1 of the actin polymerization regulating WRC-complex. Preliminary genotype-phenotype correlation indicates a profound phenotype in p.Arg87 substitutions and a more variable phenotype in other alterations. This study evidenced a variety of de novo variants in CYFIP2 as a novel cause of mostly severe intellectual disability with seizures and muscular hypotonia.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Citoplasma/metabolismo , Discapacidad Intelectual/genética , Mutación/genética , Convulsiones/genética , Niño , Preescolar , Facies , Femenino , Humanos , Lactante , Masculino , Modelos Moleculares
4.
Rev. bras. plantas med ; 16(2): 174-181, jun. 2014. graf, tab
Artículo en Portugués | LILACS | ID: lil-711773

RESUMEN

Scutellaria agrestis é utilizada por comunidades ribeirinhas do Amazonas principalmente para o tratamento de otites por via tópica utilizando-se o extrato bruto obtido por maceração. O presente trabalho visou investigar preliminarmente o perfil fitoquímico, a segurança toxicológica e as ações analgésica, anti-inflamatória e antiedematogência do extrato aquoso das folhas de S. agrestis. Foram coletados 80 indivíduos da espécie no horto medicinal da Universidade Nilton Lins, Manaus, Brasil. O perfil fitoquímico foi obtido por meio de prospecção da droga vegetal para heterosídeos cianogênicos, terpenos, compostos fenólicos e alcaloides. A toxicologia foi avaliada pelo teste de toxicidade aguda. As atividades analgésicas/ anti-inflamatórias foram analisadas por meio dos testes de formalina em camundongos e a atividade antiedematogência, pelo teste de edema de pata em ratos. Os metabólitos detectados foram fenóis (taninos hidrolisáveis, cumarinas e várias classes de flavonoides) e terpenos (esteroides livres, saponinas). Não foi possível estabelecer DL50, haja visto que o extrato não provocou a morte de nenhum animal durante o teste de toxicidade aguda, provavelmente devido à ausência de heterosídeos cianogênicos na sua composição. Apesar de não provocar morte, considerou-se que o extrato apresenta uma discreta toxicidade, uma vez que foi observada a ocorrência de espasmos na primeira hora de observação dos animais. O extrato apresentou ainda efeito analgésico e anti-inflamatório significativo nas doses de 30, 100 e 300 mg/kg pelo teste da formalina, sendo o resultado na maior dose equivalente ao obtido com a droga padrão (fentanil). No entanto, não observamos efeito antiedematogênico nas doses testadas durante as 5 horas de registro do edema de pata. Os resultados obtidos nesta pesquisa conferem base científica preliminar quanto à segurança e ao efeito analgésico e antiinflamatório da droga vegetal, o que indica que tal espécie é promissora e expressamente recomendada para maiores estudos farmacológicos in vitro e in vivo.


The Scutellaria agrestis is used by Amazonas riverine communities, especially for otitis externa topical treatment, by using the crude extract obtained by maceration. This study aimed to investigate the preliminary phytochemical profile, the safety/toxicity and the analgesic, anti-inflammatory and antiedematogenic activities of the aqueous extract of the S. agrestis leaves. Eighty individuals were collected at the Nilton Lins University medicinal garden, Manaus, Brazil. The phytochemical profile was obtained through a plant drug survey for cyanogenic heterosides, terpenes, alkaloids and phenolic compounds. The extract safety was evaluated by acute toxicity test. Analgesic and anti-inflammatory activities were accessed using formalin test in mice and the antiedematogenic activity, using paw edema test in mice. We detected phenolic (hydrolysable tannins, coumarins and several classes of flavonoids) and terpenoid (free steroids, saponins) metabolites. We could not establish LD50 because no animals died during the acute toxicity test, probably because of the absence of cyanogenic glycosides on the composition of the extract. However, we found that the extract is slightly toxic as animal spasms were observed in the first hour of the test. The extract showed significant analgesic and anti-inflammatory activity on the formalin test (30, 100 and 300 mg/kg p.o.), and the highest dose result was equivalent to the standard drug (Fentanyl). However, no significant antiedematogenic effect was observed during the paw edema test. The results obtained in this study provide preliminary scientific basis about the safety and analgesic/anti-inflammatory actions of the aqueous extract of S. agrestis, which indicates that this species is a promising option for further in vitro and in vivo pharmacological studies.


Asunto(s)
Animales , Masculino , Femenino , Ratones , Extractos Vegetales/análisis , Analgésicos/clasificación , Antiinflamatorios/clasificación , Bioensayo/instrumentación , Hojas de la Planta/anatomía & histología , Pruebas de Toxicidad Aguda , Scutellaria/metabolismo , Fitoquímicos/análisis
5.
Eur Arch Paediatr Dent ; 14(6): 405-10, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23549991

RESUMEN

INTRODUCTION: The majority of tooth agenesis cases are mild (hypodontia) and typically not associated with the gene mutations linked to oligodontia. From this, we hypothesise that most cases of tooth agenesis fit a polygenic mode of inheritance, where several genes with small effects cause a variety of varying phenotypes. MATERIALS AND METHODS: In this study, we looked at 18 not typically studied genes in this condition, to ascertain their contribution to hypodontia. Our study subjects consisted of 167 patients with hypodontia and their parents from two cohorts (one from Brazil and one from Turkey). An additional 465 DNA samples (93 cases with hypodontia and 372 controls without family history for tooth agenesis or oral clefts) from Brazil were also available for this study. Ninety-three single nucleotide polymorphisms that maximally represent the linkage disequilibrium structure of the genes for the 18 genes were selected and genotyped using Taqman chemistry. Chi square was used to test if genotype distributions were in Hardy-Weinberg equilibrium, and 24 markers that were in Hardy-Weinberg equilibrium and had allele frequencies higher than 5 % in a panel of 50 CEPH samples were further tested. Association between hypodontia and genetic variants was tested with the transmission disequilibrium test within the programme Family-Based Association Test (FBAT) and by using Chi square and Fisher's exact tests. Alpha at a level of 0.05 was used to report results. RESULTS: Results suggest possible associations between several genes and hypodontia in the three populations. In the Turkish cohort (n = 51 parent-affected child trios) the most significant results were as follows: FGF3 rs1893047, p = 0.08; GLI3 rs929387, p = 0.03; GLI3 haplotype rs929387-rs846266, p = 0.002; and PAX9 rs2073242, p = 0.03. In the Brazilian cohort (n = 116 parent-affected child trios), the results were as follows: DLX1 rs788173, p = 0.07; FGF3 rs12574452, p = 0.03; GLI2 rs1992901, p = 0.03; and PITX2 rs2595110, p = 0.01. The second Brazilian cohort also suggested that FGF3 (rs12574452, p = 0.01) is associated with hypodontia and added EDAR (rs17269487, p = 0.04), LHX6 (rs989798, p = 0.02), and MSX1 (rs12532, p = 0.003). CONCLUSION: Our results suggest that several genes are potentially associated with hypodontia and their individual contributions may be modest. Hence, these cases may not be explained by inactivating mutations such as many oligodontia cases segregating in a Mendelian fashion but rather are influenced by one or more susceptibility alleles in multiple small effect genes.


Asunto(s)
Anodoncia , Frecuencia de los Genes , Anodoncia/genética , Estudios de Casos y Controles , Genotipo , Humanos , Fenotipo , Polimorfismo de Nucleótido Simple
6.
J Med Genet ; 48(11): 767-75, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21940737

RESUMEN

BACKGROUND: Recessive mutant alleles of MYO7A, USH1C, CDH23, and PCDH15 cause non-syndromic deafness or type 1 Usher syndrome (USH1) characterised by deafness, vestibular areflexia, and vision loss due to retinitis pigmentosa. For CDH23, encoding cadherin 23, non-syndromic DFNB12 deafness is associated primarily with missense mutations hypothesised to have residual function. In contrast, homozygous nonsense, frame shift, splice site, and some missense mutations of CDH23, all of which are presumably functional null alleles, cause USH1D. The phenotype of a CDH23 compound heterozygote for a DFNB12 allele in trans configuration to an USH1D allele is not known and cannot be predicted from current understanding of cadherin 23 function in the retina and vestibular labyrinth. METHODS AND RESULTS: To address this issue, this study sought CDH23 compound heterozygotes by sequencing this gene in USH1 probands, and families segregating USH1D or DFNB12. Five non-syndromic deaf individuals were identified with normal retinal and vestibular phenotypes that segregate compound heterozygous mutations of CDH23, where one mutation is a known or predicted USH1 allele. CONCLUSIONS: One DFNB12 allele in trans configuration to an USH1D allele of CDH23 preserves vision and balance in deaf individuals, indicating that the DFNB12 allele is phenotypically dominant to an USH1D allele. This finding has implications for genetic counselling and the development of therapies for retinitis pigmentosa in Usher syndrome. ACCESSION NUMBERS: The cDNA and protein Genbank accession numbers for CDH23 and cadherin 23 used in this paper are AY010111.2 and AAG27034.2, respectively.


Asunto(s)
Cadherinas/genética , Pérdida Auditiva Sensorineural/genética , Mutación , Retina/metabolismo , Retinitis Pigmentosa/genética , Síndromes de Usher/genética , Vestíbulo del Laberinto/metabolismo , Adolescente , Adulto , Alelos , Pueblo Asiatico/genética , Enfermedades Asintomáticas , Proteínas Relacionadas con las Cadherinas , Niño , Estudios de Cohortes , Análisis Mutacional de ADN , Exones , Femenino , Estudios de Asociación Genética , Genotipo , Pérdida Auditiva Sensorineural/patología , Heterocigoto , Humanos , Masculino , Linaje , Fenotipo , Retina/patología , Retinitis Pigmentosa/patología , Estados Unidos , Síndromes de Usher/patología , Vestíbulo del Laberinto/patología , Población Blanca/genética
7.
Braz J Biol ; 69(1): 129-36, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19347155

RESUMEN

This work aimed to evaluate the effects of simulated drift of glyphosate on the morphoanatomy of three eucalypt clones and to correlate the intoxication symptoms on a microscopic scale with those observed in this visual analysis. The effects of glyphosate drift were proportional to the five doses tested, with Eucalyptus urophylla being more tolerant to the herbicide than E. grandis and urograndis hybrid. The symptoms of intoxication which were similar for the different clones at 7 and 15 days after application were characterized by leaf wilting, chlorosis and curling and, at the highest rates, by necrosis, leaf senescence and death. Anatomically glyphosate doses higher than 86.4 g.ha-1 caused cellular plasmolysis, hypertrophy and hyperplasia, formation of the cicatrization tissue and dead cells on the adaxial epidermis. The spongy parenchyma had a decrease, and the palisade parenchyma and leaf blade thickness had an increase. The increased thickness in leaf blade and palisade parenchyma may be related to the plant response to glyphosate action, as a form of recovering the photosynthetically active area reduced by necroses and leaf senescence caused by the herbicide.


Asunto(s)
Eucalyptus/efectos de los fármacos , Glicina/análogos & derivados , Herbicidas/toxicidad , Hojas de la Planta/efectos de los fármacos , Clonación de Organismos , Relación Dosis-Respuesta a Droga , Eucalyptus/anatomía & histología , Eucalyptus/citología , Eucalyptus/genética , Glicina/toxicidad , Hojas de la Planta/anatomía & histología , Hojas de la Planta/citología , Glifosato
8.
Braz. j. biol ; 69(1): 129-136, Feb. 2009. ilus, tab
Artículo en Inglés | LILACS | ID: lil-510132

RESUMEN

This work aimed to evaluate the effects of simulated drift of glyphosate on the morphoanatomy of three eucalypt clones and to correlate the intoxication symptoms on a microscopic scale with those observed in this visual analysis. The effects of glyphosate drift were proportional to the five doses tested, with Eucalyptus urophylla being more tolerant to the herbicide than E. grandis and urograndis hybrid. The symptoms of intoxication which were similar for the different clones at 7 and 15 days after application were characterized by leaf wilting, chlorosis and curling and, at the highest rates, by necrosis, leaf senescence and death. Anatomically glyphosate doses higher than 86.4 g.ha-1 caused cellular plasmolysis, hypertrophy and hyperplasia, formation of the cicatrization tissue and dead cells on the adaxial epidermis. The spongy parenchyma had a decrease, and the palisade parenchyma and leaf blade thickness had an increase. The increased thickness in leaf blade and palisade parenchyma may be related to the plant response to glyphosate action, as a form of recovering the photosynthetically active area reduced by necroses and leaf senescence caused by the herbicide.


Este trabalho teve como objetivo avaliar os efeitos da deriva simulada de glyphosate na morfoanatomia de três clones de eucalipto e correlacionar os sintomas de intoxicação em escala microscópica com aqueles observados à vista desarmada. Os efeitos da deriva do glyphosate foram proporcionais às doses testadas, sendo Eucalyptus urophylla mais tolerante ao herbicida que E. grandis e o híbrido urograndis. Os sintomas de intoxicação foram semelhantes para os diferentes clones testados, tanto aos 7 quanto aos 15 dias após a aplicação, sendo caracterizados, morfologicamente, por murcha, clorose e enrolamento foliar e, no caso das maiores doses, por necrose, senescência foliar e morte das plantas de eucalipto. Anatomicamente, doses de glyphosate superiores a 86,4 g.ha-1 provocaram plasmólise, hipertrofia e hiperplasia celular, formação de tecido de cicatrização e morte das células da face adaxial da epiderme. Observou-se diminuição na espessura do parênquima lacunoso e aumento na espessura do parênquima paliçádico e da lâmina foliar. O aumento na espessura da folha e do parênquima paliçádico podem estar relacionados à resposta das plantas ao glyphosate, como forma de compensar a área fotossinteticamente reduzida pelas necroses e senescência causadas pelo herbicida.


Asunto(s)
Eucalyptus/efectos de los fármacos , Glicina/análogos & derivados , Herbicidas/toxicidad , Hojas de la Planta/efectos de los fármacos , Clonación de Organismos , Relación Dosis-Respuesta a Droga , Eucalyptus/anatomía & histología , Eucalyptus/citología , Eucalyptus/genética , Glicina/toxicidad , Hojas de la Planta/anatomía & histología , Hojas de la Planta/citología
9.
Arch Oral Biol ; 54(1): 45-9, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18790474

RESUMEN

Tooth agenesis is a common congenital disorder that affects almost 20% of the world's population. A number of different genes have been shown to be associated with cases of tooth agenesis including AXIN2, IRF6, FGFR1, MSX1, PAX9, and TGFA. Of particular interest is AXIN2, which was linked to two families segregating oligodontia and colorectal cancer. We studied two collections of families affected with tooth agenesis and tested them for association with AXIN2. Significant association between tooth agenesis and AXIN2 was found (p=0.02) in cases with at least one missing incisor. Our work further supports a role of AXIN2 in human tooth agenesis and for the first time suggests AXIN2 is involved in sporadic forms of common incisor agenesis. Future studies should identify which specific tooth agenesis sub-phenotypes are consequence of AXIN2 genetic variations. A sub-set of these cases could have an increased susceptibility for colon cancer or other types of tumours and this knowledge would have significant clinical implications.


Asunto(s)
Anodoncia/genética , Proteínas del Citoesqueleto/genética , Mutación de Línea Germinal/genética , Polimorfismo Genético , Proteína Axina , Estudios de Casos y Controles , Neoplasias del Colon/genética , Femenino , Predisposición Genética a la Enfermedad , Humanos , Incisivo/anomalías , Masculino , Saliva/metabolismo
10.
Retin Cases Brief Rep ; 1(4): 232-5, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-25390987

RESUMEN

PURPOSE: To report variations in the inheritance pattern and clinical presentation of crystalline retinopathies. METHODS: Two different families with crystalline retinopathy were studied with a complete family history and ophthalmologic examination including Goldmann kinetic perimetry and electroretinography. Genetic studies were performed in one of the families. RESULTS: One of the families had a clearly autosomal dominant mode of inheritance while the other family most likely follows an autosomal recessive pattern. Several members in each family had significant retinal pigment epithelial atrophy, intraretinal crystals, relatively pink optic nerves, and paracentral visual field defects, all of which are clinical features resembling those of Bietti crystalline retinopathy. Examination of peripheral leukocytes using transmission electron microscopy in selected affected members showed no evidence of classical lysosomal crystals that are characteristics for Bietti crystalline retinopathy. No pathogenic mutations were identified in the CYP4V2 gene. CONCLUSIONS: Not all crystalline retinopathies are Bietti's. Further genetic, biochemical, and pathologic studies are required to better differentiate between these retinopathies.

11.
J Dent Res ; 83(9): 723-7, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15329380

RESUMEN

In this study, we sought to determine the association between tooth agenesis and DNA sequence variation in the genes MSX1 and PAX9 in an ethnically diverse human population. Since cleft lip/palate is also associated with both tooth agenesis and the gene TGFA, we included TGFA in the analysis as well. Cheek swab samples were obtained for DNA analysis from 116 case/parent trios. Probands had at least one developmentally missing tooth, excluding third molars. Genotyping was performed by single-strand conformational polymorphism or kinetic polymerase chain-reaction assays. Transmission distortion of the marker alleles and DNA sequence analysis was performed. Results showed that tooth agenesis is associated with markers of the genes MSX1 and TGFA. No mutations were found in MSX1 or PAX9 coding regions. There were statistically significant data suggesting that MSX1 interacts with PAX9. These findings suggest that MSX1, PAX9, and TGFA play a role in isolated dental agenesis.


Asunto(s)
Anodoncia/genética , Proteínas de Unión al ADN/genética , Proteínas de Homeodominio/genética , Factores de Transcripción/genética , Factor de Crecimiento Transformador alfa/genética , Adolescente , Adulto , Alelos , Emparejamiento Base/genética , Niño , Exones/genética , Femenino , Marcadores Genéticos/genética , Genotipo , Haplotipos , Humanos , Intrones/genética , Factor de Transcripción MSX1 , Masculino , Persona de Mediana Edad , Factor de Transcripción PAX9 , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Análisis de Secuencia de ADN
12.
Folha méd ; 88(3): 64-70, 1984.
Artículo en Portugués | LILACS | ID: lil-20686

Asunto(s)
Humanos , Anciano , Hipertensión
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