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1.
Am J Hum Genet ; 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39226897

RESUMO

Retinitis pigmentosa (RP) is a Mendelian disease characterized by gradual loss of vision, due to the progressive degeneration of retinal cells. Genetically, it is highly heterogeneous, with pathogenic variants identified in more than 100 genes so far. Following a large-scale sequencing screening, we identified five individuals (four families) with recessive and non-syndromic RP, carrying as well bi-allelic DNA changes in COQ8B, a gene involved in the biosynthesis of coenzyme Q10. Specifically, we detected compound heterozygous assortments of five disease-causing variants (c.187C>T [p.Arg63Trp], c.566G>A [p.Trp189Ter], c.1156G>A [p.Asp386Asn], c.1324G>A [p.Val442Met], and c.1560G>A [p.Trp520Ter]), all segregating with disease according to a recessive pattern of inheritance. Cell-based analysis of recombinant proteins deriving from these genotypes, performed by target engagement assays, showed in all cases a significant decrease in ligand-protein interaction compared to the wild type. Our results indicate that variants in COQ8B lead to recessive non-syndromic RP, possibly by impairing the biosynthesis of coenzyme Q10, a key component of oxidative phosphorylation in the mitochondria.

2.
Am J Hum Genet ; 111(4): 701-713, 2024 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-38531366

RESUMO

Copy-number variants (CNVs) play a substantial role in the molecular pathogenesis of hereditary disease and cancer, as well as in normal human interindividual variation. However, they are still rather difficult to identify in mainstream sequencing projects, especially involving exome sequencing, because they often occur in DNA regions that are not targeted for analysis. To overcome this problem, we developed OFF-PEAK, a user-friendly CNV detection tool that builds on a denoising approach and the use of "off-target" DNA reads, which are usually discarded by sequencing pipelines. We benchmarked OFF-PEAK on data from targeted sequencing of 96 cancer samples, as well as 130 exomes of individuals with inherited retinal disease from three different populations. For both sets of data, OFF-PEAK demonstrated excellent performance (>95% sensitivity and >80% specificity vs. experimental validation) in detecting CNVs from in silico data alone, indicating its immediate applicability to molecular diagnosis and genetic research.


Assuntos
Algoritmos , Neoplasias , Humanos , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA , Exoma , Variações do Número de Cópias de DNA/genética , Neoplasias/genética
3.
Am J Hum Genet ; 111(9): 2012-2030, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39191256

RESUMO

Genome analysis of individuals affected by retinitis pigmentosa (RP) identified two rare nucleotide substitutions at the same genomic location on chromosome 11 (g.61392563 [GRCh38]), 69 base pairs upstream of the start codon of the ciliopathy gene TMEM216 (c.-69G>A, c.-69G>T [GenBank: NM_001173991.3]), in individuals of South Asian and African ancestry, respectively. Genotypes included 71 homozygotes and 3 mixed heterozygotes in trans with a predicted loss-of-function allele. Haplotype analysis showed single-nucleotide variants (SNVs) common across families, suggesting ancestral alleles within the two distinct ethnic populations. Clinical phenotype analysis of 62 available individuals from 49 families indicated a similar clinical presentation with night blindness in the first decade and progressive peripheral field loss thereafter. No evident systemic ciliopathy features were noted. Functional characterization of these variants by luciferase reporter gene assay showed reduced promotor activity. Nanopore sequencing confirmed the lower transcription of the TMEM216 c.-69G>T allele in blood-derived RNA from a heterozygous carrier, and reduced expression was further recapitulated by qPCR, using both leukocytes-derived RNA of c.-69G>T homozygotes and total RNA from genome-edited hTERT-RPE1 cells carrying homozygous TMEM216 c.-69G>A. In conclusion, these variants explain a significant proportion of unsolved cases, specifically in individuals of African ancestry, suggesting that reduced TMEM216 expression might lead to abnormal ciliogenesis and photoreceptor degeneration.


Assuntos
Linhagem , Polimorfismo de Nucleotídeo Único , Retinose Pigmentar , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Adulto Jovem , Alelos , Haplótipos , Heterozigoto , Homozigoto , Proteínas de Membrana/genética , Fenótipo , Retinose Pigmentar/genética , Retinose Pigmentar/patologia
4.
Hum Mol Genet ; 32(4): 595-607, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36084042

RESUMO

The purpose of this paper is to identify likely pathogenic non-coding variants in inherited retinal dystrophy (IRD) genes, using genome sequencing (GS). Patients with IRD were recruited to the study and underwent comprehensive ophthalmological evaluation and GS. The results of GS were investigated through virtual gene panel analysis, and plausible pathogenic variants and clinical phenotype evaluated by the multidisciplinary team (MDT) discussion. For unsolved patients in whom a specific gene was suspected to harbor a missed pathogenic variant, targeted re-analysis of non-coding regions was performed on GS data. Candidate variants were functionally tested by messenger RNA analysis, minigene or luciferase reporter assays. Previously unreported, likely pathogenic, non-coding variants in 7 genes (PRPF31, NDP, IFT140, CRB1, USH2A, BBS10 and GUCY2D), were identified in 11 patients. These were shown to lead to mis-splicing (PRPF31, IFT140, CRB1 and USH2A) or altered transcription levels (BBS10 and GUCY2D). MDT-led, phenotype-driven, non-coding variant re-analysis of GS is effective in identifying the missing causative alleles.


Assuntos
Distrofias Retinianas , Humanos , Mutação , Linhagem , Distrofias Retinianas/diagnóstico , Distrofias Retinianas/genética , Sequenciamento Completo do Genoma , Equipe de Assistência ao Paciente , Análise Mutacional de DNA/métodos , Proteínas do Olho/genética , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética
5.
Genet Med ; 26(6): 101106, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38420906

RESUMO

PURPOSE: Inherited retinal diseases (IRDs) are a group of monogenic conditions that can lead to progressive blindness. Their missing heritability is still considerable, due in part to the presence of disease genes that await molecular identification. The purpose of this work was to identify novel genetic associations with IRDs. METHODS: Patients underwent a comprehensive ophthalmological evaluation using standard-of-care tests, such as detailed retinal imaging (macular optical coherence tomography and short-wavelength fundus autofluorescence) and electrophysiological testing. Exome and genome sequencing, as well as computer-assisted data analysis were used for genotyping and detection of DNA variants. A minigene-driven splicing assay was performed to validate the deleterious effects of 1 of such variants. RESULTS: We identified 8 unrelated families from Hungary, the United States, Israel, and The Netherlands with members presenting with a form of autosomal recessive and nonsyndromic retinal degeneration, predominantly described as rod-cone dystrophy but also including cases of cone/cone-rod dystrophy. Age of disease onset was very variable, with some patients experiencing first symptoms during their fourth decade of life or later. Myopia greater than 5 diopters was present in 5 of 7 cases with available refractive data, and retinal detachment was reported in 2 cases. All ascertained patients carried biallelic loss-of-function variants in UBAP1L (HGNC: 40028), a gene with unknown function and with homologies to UBAP1, encoding a protein involved in ubiquitin metabolism. One of these pathogenic variants, the intronic NM_001163692.2:c.910-7G>A substitution, was identified in 5 unrelated families. Minigene-driven splicing assays in HEK293T cells confirmed that this DNA change is responsible for the creation of a new acceptor splice site, resulting in aberrant splicing. CONCLUSION: We identified UBAP1L as a novel IRD gene. Although its function is currently unknown, UBAP1L is almost exclusively expressed in photoreceptors and the retinal pigment epithelium, hence possibly explaining the link between pathogenic variants in this gene and an ocular phenotype.


Assuntos
Linhagem , Degeneração Retiniana , Humanos , Masculino , Feminino , Adulto , Degeneração Retiniana/genética , Pessoa de Meia-Idade , Mutação com Perda de Função , Genes Recessivos , Criança , Adolescente , Distrofias de Cones e Bastonetes/genética , Hungria , Adulto Jovem , Predisposição Genética para Doença
6.
Graefes Arch Clin Exp Ophthalmol ; 262(6): 1883-1897, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38189974

RESUMO

PURPOSE: Retinitis pigmentosa (RP) comprises a genetically and clinically heterogeneous group of inherited retinal degenerations, where 20-30% of patients exhibit extra-ocular manifestations (syndromic RP). Understanding the genetic profile of RP has important implications for disease prognosis and genetic counseling. This study aimed to characterize the genetic profile of syndromic RP in Portugal. METHODS: Multicenter, retrospective cohort study. Six Portuguese healthcare providers identified patients with a clinical diagnosis of syndromic RP and available genetic testing results. All patients had been previously subjected to a detailed ophthalmologic examination and clinically oriented genetic testing. Genetic variants were classified according to the American College of Medical Genetics and Genomics; only likely pathogenic or pathogenic variants were considered relevant for disease etiology. RESULTS: One hundred and twenty-two patients (53.3% males) from 100 families were included. Usher syndrome was the most frequent diagnosis (62.0%), followed by Bardet-Biedl (19.0%) and Senior-Løken syndromes (7.0%). Deleterious variants were identified in 86/100 families for a diagnostic yield of 86.0% (87.1% for Usher and 94.7% for Bardet-Biedl). A total of 81 genetic variants were identified in 25 different genes, 22 of which are novel. USH2A and MYO7A were responsible for most type II and type I Usher syndrome cases, respectively. BBS1 variants were the cause of Bardet-Biedl syndrome in 52.6% of families. Best-corrected visual acuity (BCVA) records were available at baseline and last visit for 99 patients (198 eyes), with a median follow-up of 62.0 months. The mean BCVA was 56.5 ETDRS letters at baseline (Snellen equivalent ~ 20/80), declining to 44.9 ETDRS letters (Snellen equivalent ~ 20/125) at the last available follow-up (p < 0.001). CONCLUSION: This is the first multicenter study depicting the genetic profile of syndromic RP in Portugal, thus contributing toward a better understanding of this heterogeneous disease group. Usher and Bardet-Biedl syndromes were found to be the most common types of syndromic RP in this large Portuguese cohort. A high diagnostic yield was obtained, highlighting current genetic testing capabilities in providing a molecular diagnosis to most affected individuals. This has major implications in determining disease-related prognosis and providing targeted genetic counseling for syndromic RP patients in Portugal.


Assuntos
Testes Genéticos , Mutação , Retinose Pigmentar , Humanos , Retinose Pigmentar/genética , Retinose Pigmentar/diagnóstico , Retinose Pigmentar/epidemiologia , Portugal/epidemiologia , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Adulto , Adolescente , Adulto Jovem , Criança , Idoso , Linhagem , Síndromes de Usher/genética , Síndromes de Usher/diagnóstico , Síndromes de Usher/epidemiologia , Pré-Escolar , Análise Mutacional de DNA , Seguimentos , DNA/genética , Proteínas do Olho/genética
7.
Artigo em Inglês | MEDLINE | ID: mdl-39251413

RESUMO

PURPOSE: The influence of rurality on the duration of untreated psychosis (DUP) in first-episode psychosis (FEP) is poorly understood. We investigated factors associated with FEP in rural/urban settings and whether there are rural/urban differences in DUP and the mode (speed) of onset of psychosis. METHODS: We used the Cambridgeshire and Peterborough NHS Foundation Trust Research Database (CPFTRD) to identify all persons presenting to an early intervention for psychosis service with FEP between 2013 and 2015. We performed descriptive statistics and multivariable linear and multinomial regression to assess the relationships between the study outcomes and the independent variables. RESULTS: One hundred and fifty-five FEP patients were identified, with a mean age of 23.4 (SD, 5.3) years. The median DUP was 129.0 (IQR: 27.5-524.0) days. In rural areas, FEP patients were more likely to be employed and live with family than those in urban areas. A longer DUP was observed among patients with an insidious onset of psychosis compared with an acute onset (619.5 (IQR: 333.5-945.0)) vs. (17.0 (IQR: 8.0-30.5)) days respectively, p < 0.0001. We found evidence that the mode of onset of psychosis differed by employment status and living circumstances. There was insufficient evidence of rural/urban differences in DUP and mode of onset of psychosis. CONCLUSIONS: Our results suggest that the mode of onset of psychosis is an important indicator of treatment delay and could provide vital information for service planning and delivery. Sociodemographic variations in FEP exist in rural populations, and our findings are similar to those observed in urban settings.

8.
Ophthalmic Res ; 67(1): 448-457, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39079514

RESUMO

INTRODUCTION: The purpose of this project was to explore the current standards of clinical care genetic testing and counseling for patients with inherited retinal diseases (IRDs) from the perspective of leading experts in selected European countries. Also, to gather opinions on current bottlenecks and future solutions to improve patient care. METHODS: On the initiative of the European Vision Institute, a survey questionnaire with 41 questions was designed and sent to experts in the field from ten European countries. Each participant was asked to answer with reference to the situation in their own country. RESULTS: Sixteen questionnaires were collected by November 2023. IRD genetic tests are performed in clinical care settings for 80% or more of tested patients in 9 countries, and the costs of genetic tests in clinical care are covered by the public health service to the extent of 90% or more in 8 countries. The median proportion of patients who are genetically tested, the median rate of genetically solved patients among those who are tested, and the median proportion of patients receiving counseling are 51-70%, 61-80%, and 61-80%, respectively. Improving the education of healthcare professionals who facilitate patient referrals to specialized centers, improving access of patients to more thorough genotyping, and increasing the number of available counselors were the most advocated solutions. CONCLUSION: There is a significant proportion of IRD patients who are not genetically tested, whose genetic testing is inconclusive, or who do not receive counseling. Educational programs, greater availability of state-of-the-art genotyping and genetic counselors could improve healthcare for IRD patients.


Assuntos
Testes Genéticos , Doenças Retinianas , Humanos , Testes Genéticos/métodos , Europa (Continente) , Doenças Retinianas/genética , Doenças Retinianas/diagnóstico , Inquéritos e Questionários , Aconselhamento Genético
9.
Mar Drugs ; 22(5)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38786585

RESUMO

The process of crosslinking improves the physicochemical properties of biopolymer-based composites, making them valuable for biomedical applications. EDC/NHS-crosslinked collagen materials have a significant potential for tissue engineering applications, due to their enhanced properties and biocompatibility. Chemical crosslinking of samples can be carried out in several ways, which is crucial and has a direct effect on the final properties of the obtained material. In this study, the effect of crosslinking conditions on the properties of collagen films using EDC and NHS was investigated. Studies included FTIR spectroscopy, AFM, swelling and degradation tests, mechanical testing and contact angle measurements. Evaluation of prepared collagen films indicated that both crosslinking agents and crosslinking conditions influenced film properties. Notable alternations were observed in the infrared spectrum of the sample, to which EDC was added directly to the fish collagen solution. The same sample indicated the lowest Young modulus, tensile strength and breaking force parameters and the highest elongation at break. All samples reached the maximum swelling degree two hours after immersion in PBS solution; however, the immersion-crosslinked samples exhibited a significantly lower degree of swelling and were highly durable. The highest roughness was observed for the collagen film crosslinked with EDC, whereas the lowest was observed for the specimen crosslinked with EDC with NHS addition. The crosslinking agents increased the surface roughness of the collagen film, except for the sample modified with the addition of EDC and NHS mixture. All films were characterized by hydrophilic character. The films' modification resulted in a decrease in their hydrophilicity and wettability. Our research allows for a comparison of proposed EDC/NHS crosslinking conditions and their influence on the physicochemical properties of fish collagen thin films. EDC and NHS are promising crosslinking agents for the modification of fish collagen used in biomedical applications.


Assuntos
Materiais Biocompatíveis , Colágeno , Reagentes de Ligações Cruzadas , Peixes , Animais , Reagentes de Ligações Cruzadas/química , Colágeno/química , Materiais Biocompatíveis/química , Resistência à Tração , Engenharia Tecidual/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Teste de Materiais , Carbodi-Imidas/química
10.
J Occup Rehabil ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664361

RESUMO

PURPOSE: Return-to-work (RTW) after absence due to a mental illness is a largely understudied area, especially in industries already struggling with retention like those posing unique and high risks for public or personal safety (i.e., pilots, police officers, and health professionals), otherwise known as safety-sensitive sectors. The goal of this paper is to examine how RTW coordinators work with individuals who took a leave of absence for mental illness in safety-sensitive occupations and navigate the RTW process. METHODS: Qualitative methodology was utilized to explore the experiences of 47 RTW coordinators who had worked with individuals employed in safety-sensitive industries. The participants were recruited across Canada using convenience sampling to participate in semi-structured interviews. The interviews were transcribed, anonymized, uploaded to NVIVO 11, and coded using inductive thematic analysis. RESULTS: Our analysis shows that despite the presumed rigidity of occupational health and safety standards for safety-sensitive positions, the notion of "safety" becomes ambiguous in navigating RTW processes, and concerns about safety are often interpreted as the potential risk workers may pose to themselves, other individuals, or the workplace image. Institutional constraints of safety-sensitive jobs shape the ability of RTW coordinators to advocate on behalf of the workers, ultimately placing the workers at a disadvantage by prioritizing safety concerns for organizations over employees' needs. CONCLUSION: It is important to consider how to protect workers in safety-sensitive occupations during the RTW process after absence due to a mental illness to ensure effective integration to the workplace.

11.
Org Biomol Chem ; 21(46): 9182-9191, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37955209

RESUMO

Reaction of L-cysteine with carbonyl compounds leads to thiazolidine derivatives which undergo a stereoselective conversion to two types of chiral bicyclic products bearing two or three stereogenic centers, including the first fused oxathiane-γ-lactam system.

12.
Molecules ; 26(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34500600

RESUMO

Carbon-carbon bond forming reactions, such as aldol reaction and condensation, belong to extremely desired transformations as manifested by >25,000 entries in SciFinder. Their stereoselective variant requires the use of an appropriate catalyst with a strictly defined structure. Hence, chiral 2-azabicycloalkane-based catalysts were designed, synthesized and tested in a stereoselective aldol reaction between cyclic/acyclic ketone and p-nitrobenzaldehyde both in organic and aqueous media. Among catalysts containing a chiral bicyclic backbone, amide based on 2-azabicyclo[3.2.1]octane and pyrrolidine units showed the best catalytic activity and afforded aldol product in excellent chemical yields (up to 95%) and good diastereo- and enantioselectivity (dr 22:78, ee up to 63%).


Assuntos
Aminoácidos/química , Cicloparafinas/química , Poliaminas/química , Amidas/química , Carbono/química , Catálise , Cetonas/química , Pirrolidinas/química , Estereoisomerismo
13.
Molecules ; 25(10)2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32443610

RESUMO

A series of chiral sulfonamides containing the 2-azabicycloalkane scaffold were prepared from aza-Diels-Alder cycloadducts through their conversion to amines based on 2-azanorbornane or the bridged azepane skeleton, followed by the reaction with sulfonyl chlorides. The cytotoxic activity of the obtained bicyclic derivatives was evaluated using human hepatocellular carcinoma (HCC), medulloblastoma (MB), and glioblastoma (GBM) cell lines. Chosen compounds were shown to notably reduce cell viability as compared to nonmalignant cells.


Assuntos
Alcanos/química , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Sulfonamidas/química , Alcanos/síntese química , Alcanos/farmacologia , Aminas/síntese química , Aminas/química , Aminas/farmacologia , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/patologia , Estrutura Molecular , Estereoisomerismo , Sulfonamidas/síntese química , Sulfonamidas/farmacologia
14.
Australas J Dermatol ; 60(4): e267-e271, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30941744

RESUMO

Peptides stimulating synthesis of extracellular matrix are now commonly used in the production of anti-ageing cosmetics. However, much uncertainty still exists about the methodology of their clinical assessment. The aim of the study was to review the literature for clinical study designs assessing the efficacy of these peptides. The authors searched systematically publications indexed in PubMed, Scope and Web of Science, according to the PRISMA protocol. Altogether 12 scientific papers, reporting results of 15 independent studies were identified. Out of these 15 studies, only six used a placebo control. Double-blinding was applied in five out of 15 studies. Nine studies were based on female-only populations. For the product performance evaluation, most of the studies (10 out of the 15) used image-based methods. The literature on the topic is sparse. The studies carried out so far have many methodological limitations. Most of the clinical experiments hitherto conducted were non-double-blind and used no placebo control. There is a need for better planned and controlled clinical trials in this area.


Assuntos
Cosméticos , Matriz Extracelular/metabolismo , Biossíntese Peptídica , Envelhecimento da Pele/fisiologia , Administração Tópica , Proteínas da Matriz Extracelular/metabolismo , Humanos , Peptídeos/metabolismo
15.
Histochem Cell Biol ; 149(3): 245-260, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29164337

RESUMO

During the growth period, in surface habitats, spiders catch enough prey to feed normally. In contrast, in the cave entrance zone, prey may be relatively scarce. Meta menardi inhabits this cave section, resulting in temporary starvation. We studied structural changes in the midgut epithelial cells of M. menardi during a short-term and a medium-term controlled starvation to mimic the occasional starvation in caves, during spring and autumn. Digestive cells, secretory cells and adipocytes were examined before the experimental starvation, in the middle and at the end of starvation. We used light microscopy, transmission electron microscopy and specific histochemical methods for the detection of lipids, polysaccharides and proteins. Detection of lysosomes, autolysosomes and apoptosis was also carried out. The general structures of the cells did not change during the experimental starvation in either season, while some specific differences in the ultrastructure were observed. In both sexes, in both seasons, the amounts of lipids, glycogen and proteins decreased during starvation. Larger amounts of lipids were found in autumn, while there were no significant differences in the amounts of glycogen and proteins. In both sexes, in both seasons, autophagy and apoptosis intensified with starvation in progress, but more intensively in females. Thus, autumn individuals, in contrast to spring ones, compile energy-supplying stores to confront the subsequent winter deficiency of prey in caves, while the cellular ultrastructures undergo the same starvation-dependant changes at any time during the growth period.


Assuntos
Células Epiteliais/química , Células Epiteliais/metabolismo , Estações do Ano , Aranhas/citologia , Animais , Feminino , Lipídeos/análise , Masculino , Polissacarídeos/análise , Proteínas/análise
16.
Case Rep Ophthalmol ; 15(1): 230-237, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500542

RESUMO

Introduction: The GNB1 (guanine nucleotide-binding protein, ß1) gene encodes for the ubiquitous ß1 subunit of heterotrimeric G proteins, which are associated with G-protein-coupled receptors (GPCRs). GNB1 mutations cause a neurodevelopmental disorder characterized by a broad clinical spectrum. A novel variant has recently been confirmed in a case of rod-cone dystrophy. Case Presentation: We describe the second confirmed case of a classical rod-cone dystrophy associated with a mutation located in exon 6 of GNB1 [NM_002074.5:c.217G>C, p.(Ala73Pro)] in a 56-year-old patient also presenting mild intellectual disability, attention deficit/hyperactivity disorder, and truncal obesity. Conclusion: This paper confirms the role of GNB1 in the pathogenesis of a classic rod-cone dystrophy and highlights the importance of including this gene in the genetic analysis panel for inherited retinal diseases.

17.
Soc Sci Med ; 341: 116554, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38160608

RESUMO

The literature on professional socialization focuses on how students adopt and internalize professional identities and values, and assumes that boundary work is essential to learning how best to practice their profession. However, a focus on boundary work in the context of midwifery training - which is embedded in the gendered and hierarchical landscape of maternity care - is lacking. Thus, this article examines how Canadian student-midwives learn to navigate and negotiate interprofessional boundaries. Grounded in a symbolic interactionist approach, it draws on 31 semi-structured qualitative interviews from a mixed-methods national study on midwifery retention, explores how midwifery students make sense of the tensions among midwives, physicians, and nurses, and describes what strategies they utilize when navigating boundaries. Our analysis, based in constructivist grounded theory, revealed that participants learned about interprofessional tensions in clinical placement encounters via direct or indirect interactions with other healthcare professionals, and that strategies to navigate these tensions included educating others about midwifery training and adopting a learner identity. This article proposes that the process of professional socialization enables to reshape professional boundaries and that students are not only learners but also agents of change. These findings may yield practical applications in health education by highlighting opportunities for improving interprofessional collaborations.


Assuntos
Serviços de Saúde Materna , Tocologia , Humanos , Feminino , Gravidez , Canadá , Pesquisa Qualitativa , Estudantes , Relações Interprofissionais
18.
Materials (Basel) ; 17(7)2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38611990

RESUMO

The aim of this research was the modification of fish collagen films with various amounts of dialdehyde starch (DAS). Film properties were examined before and after the cross-linking process by DAS. Prepared biopolymer materials were characterized by Fourier Transform Infrared Spectroscopy and Atomic Force Microscopy. Moreover, the mechanical, thermal and swelling properties of the films were evaluated and the contact angle was measured. Research has shown that dialdehyde starch applied as a cross-linking agent influences collagen film properties. Mechanical testing indicated a decrease in Young's Modulus and an increase in breaking force, elongation at break, and tensile strength parameters. Results for contact angle were significantly higher for collagen films cross-linked with DAS; thus, the hydrophilicity of samples decreased. Modified samples presented a lower swelling degree in PBS than native collagen films. However, the highest values for the degree of swelling among the modified specimens were obtained from the 1% DAS samples, which were 717% and 702% for 1% and 2% collagen, respectively. Based on AFM images and roughness values, it was noticed that DAS influenced collagen film surface morphology. The lowest value of Rq was observed for 2%Coll_2%DAS and was approximately 10 nm. Analyzing thermograms for collagen samples, it was observed that pure collagen samples were less thermally stable than cross-linked ones. Dialdehyde starch is a promising cross-linking agent for collagen extracted from fish skin and may increase its applicability.

19.
Genes (Basel) ; 15(8)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39202371

RESUMO

We present the results of the first study of a large cohort of patients with inherited retinal dystrophies (IRD) performed for the Polish population using whole-exome sequencing (WES) in the years 2016-2019. Moreover, to facilitate such diagnostic analyses and enable future application of gene therapy and genome editing for IRD patients, a Polish genomic reference database (POLGENOM) was created based on whole-genome sequences of healthy Polish Caucasian nonagenarians and centenarians. The newly constructed database served as a control, providing a comparison for variant frequencies in the Polish population. The diagnostic yield for the selected group of IRD patients reached 64.9%. The study uncovered the most common pathogenic variants in ABCA4 and USH2A in the European population, along with several novel causative variants. A significant frequency of the ABCA4 complex haplotype p.(Leu541Pro; Ala1038Val) was observed, as well as that of the p.Gly1961Glu variant. The first VCAN causative variant NM_004385.5:c.4004-2A>G in Poland was found and described. Moreover, one of the first patients with the RPE65 causative variants was identified, and, in consequence, could receive the dedicated gene therapy. The availability of the reference POLGENOM database enabled comprehensive variant characterisation during the NGS data analysis, confirming the utility of a population-specific genomic database for enhancing diagnostic accuracy. Study findings suggest the significance of genetic testing in elder patients with unclear aetiology of eye diseases. The combined approach of NGS and the reference genomic database can improve the diagnosis, management, and future treatment of IRDs.


Assuntos
Sequenciamento do Exoma , Distrofias Retinianas , População Branca , Humanos , Distrofias Retinianas/genética , Polônia , Masculino , População Branca/genética , Feminino , Sequenciamento do Exoma/métodos , Proteínas da Matriz Extracelular/genética , Bases de Dados Genéticas , Transportadores de Cassetes de Ligação de ATP/genética , Idoso de 80 Anos ou mais , cis-trans-Isomerases/genética , Idoso , Pessoa de Meia-Idade , Adulto , Mutação
20.
Skin Res Technol ; 19(1): e200-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22671986

RESUMO

BACKGROUND/PURPOSE: The knowledge how surfactants and hydrolyzed proteins influence the elastic properties of living epidermal keratinocytes is sparse. We demonstrate that the stiffness of cells measured by atomic force microscope (AFM) can be correlated with viability test. METHODS AND MATERIALS: The effects of sodium lauryl sulphate (SLS) and hydrolyzed collagen (HK) of molecular weight 9 kDa were examined with respect to human keratinocytes viability and elasticity. MTT assay was applied to determine the survival fraction of keratinocytes treated with SLS and HK solutions of various molar ratios. The AFM measurements of the keratinocytes stiffness were carried out immediately after the exposure of cells to the SLS and HK, respectively. RESULTS: The increase of the SLS concentration resulted in the decrease of cells proliferation and this effect was inhibited by addition of HK. The strongest inhibition was observed for the SLS:HK molar ratio equals to 2:1. AFM study shows decrease in the cell stiffness for cells treated with SLS. Fluorescence microscopy reveals remodeling of actin filaments of SLS-treated cells. SLS:HK mixture treatment results in mechanical stiffness close to untreated cells. CONCLUSION: These results provide possible correlations between mechanical properties and viability of keratinocytes when the chemical stress occurs.


Assuntos
Colágeno/toxicidade , Elasticidade/efeitos dos fármacos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Modelos Biológicos , Tensoativos/toxicidade , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/fisiologia , Antígenos de Superfície/efeitos dos fármacos , Antígenos de Superfície/fisiologia , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/fisiologia , Elasticidade/fisiologia , Humanos , Hidrólise , Queratinócitos/fisiologia , Microscopia de Força Atômica , Dodecilsulfato de Sódio/toxicidade
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