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1.
J Med Genet ; 61(3): 250-261, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38050128

RESUMO

BACKGROUND: Classic aniridia is a highly penetrant autosomal dominant disorder characterised by congenital absence of the iris, foveal hypoplasia, optic disc anomalies and progressive opacification of the cornea. >90% of cases of classic aniridia are caused by heterozygous, loss-of-function variants affecting the PAX6 locus. METHODS: Short-read whole genome sequencing was performed on 51 (39 affected) individuals from 37 different families who had screened negative for mutations in the PAX6 coding region. RESULTS: Likely causative mutations were identified in 22 out of 37 (59%) families. In 19 out of 22 families, the causative genomic changes have an interpretable deleterious impact on the PAX6 locus. Of these 19 families, 1 has a novel heterozygous PAX6 frameshift variant missed on previous screens, 4 have single nucleotide variants (SNVs) (one novel) affecting essential splice sites of PAX6 5' non-coding exons and 2 have deep intronic SNV (one novel) resulting in gain of a donor splice site. In 12 out of 19, the causative variants are large-scale structural variants; 5 have partial or whole gene deletions of PAX6, 3 have deletions encompassing critical PAX6 cis-regulatory elements, 2 have balanced inversions with disruptive breakpoints within the PAX6 locus and 2 have complex rearrangements disrupting PAX6. The remaining 3 of 22 families have deletions encompassing FOXC1 (a known cause of atypical aniridia). Seven of the causative variants occurred de novo and one cosegregated with familial aniridia. We were unable to establish inheritance status in the remaining probands. No plausibly causative SNVs were identified in PAX6 cis-regulatory elements. CONCLUSION: Whole genome sequencing proves to be an effective diagnostic test in most individuals with previously unexplained aniridia.


Assuntos
Aniridia , Anormalidades do Olho , Humanos , Fator de Transcrição PAX6/genética , Aniridia/genética , Mutação/genética , Anormalidades do Olho/genética , Éxons , Proteínas de Homeodomínio/genética , Proteínas do Olho/genética , Linhagem
2.
Nurse Educ ; 46(6): E189-E192, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669670

RESUMO

BACKGROUND: The advancement of technological tools fosters constant change in nursing education. Institutional help desk reports classify data sets based on topic and source. These aggregate data may be useful in supporting nursing faculty adaptation to technological change. PURPOSE: In an endeavor to identify and address persistent barriers to technological adaptation by nursing faculty, help desk data were reviewed to identify trends and implications of such trends. METHODS: Within the context of a single-purpose, private nursing college, the findings of help desk reports were assessed to identify the source of technological barriers and potential paths toward addressing these barriers. RESULTS: The help desk reports identify pronounce areas in which faculty frequently seek assistance. In addition, the reports disclose unique tendencies in nursing faculty to collaborate with peers for assistance. CONCLUSIONS: The trends identified within the records provide an evidence-based foundation for efforts to support effective faculty development interventions.


Assuntos
Educação em Enfermagem , Docentes de Enfermagem , Humanos , Pesquisa em Educação em Enfermagem , Universidades
3.
Nurs Adm Q ; 45(2): 159-168, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33570884

RESUMO

The impact of the global coronavirus disease-2019 (COVID-19) pandemic has triggered changes in nursing education at a pace not previously experienced in academia. Academic nursing leaders have been faced with challenges of balancing the impact of the pandemic responses in the face-to-face classroom, laboratory, and clinical learning, ensuring the safety of the college community, and supporting alternative educational delivery formats with assurance that desired learning outcomes and demanded professional competencies are attained. The challenge faced by these leaders is unprecedented. However, there is opportunity in crisis for leaders. This article details how the leadership at one institution leveraged transformational change theory to support faculty, staff, and students during this time of rapid change. Additionally, the article discusses the use of transformational change theory and the ongoing institutional commitment to meeting curricular goals and objectives while maintaining a commitment to being student focused.


Assuntos
Bacharelado em Enfermagem/organização & administração , Docentes de Enfermagem/organização & administração , Liderança , COVID-19/epidemiologia , Currículo , Bacharelado em Enfermagem/tendências , Humanos , Pandemias , SARS-CoV-2
4.
J Clin Endocrinol Metab ; 105(5)2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32034419

RESUMO

CONTEXT: The reproductive axis is controlled by a network of gonadotropin-releasing hormone (GnRH) neurons born in the primitive nose that migrate to the hypothalamus alongside axons of the olfactory system. The observation that congenital anosmia (inability to smell) is often associated with GnRH deficiency in humans led to the prevailing view that GnRH neurons depend on olfactory structures to reach the brain, but this hypothesis has not been confirmed. OBJECTIVE: The objective of this work is to determine the potential for normal reproductive function in the setting of completely absent internal and external olfactory structures. METHODS: We conducted comprehensive phenotyping studies in 11 patients with congenital arhinia. These studies were augmented by review of medical records and study questionnaires in another 40 international patients. RESULTS: All male patients demonstrated clinical and/or biochemical signs of GnRH deficiency, and the 5 men studied in person had no luteinizing hormone (LH) pulses, suggesting absent GnRH activity. The 6 women studied in person also had apulsatile LH profiles, yet 3 had spontaneous breast development and 2 women (studied from afar) had normal breast development and menstrual cycles, suggesting a fully intact reproductive axis. Administration of pulsatile GnRH to 2 GnRH-deficient patients revealed normal pituitary responsiveness but gonadal failure in the male patient. CONCLUSIONS: Patients with arhinia teach us that the GnRH neuron, a key gatekeeper of the reproductive axis, is associated with but may not depend on olfactory structures for normal migration and function, and more broadly, illustrate the power of extreme human phenotypes in answering fundamental questions about human embryology.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Neurônios/fisiologia , Nariz/anormalidades , Transtornos do Olfato/congênito , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/metabolismo , Anormalidades Múltiplas/patologia , Anormalidades Múltiplas/fisiopatologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/deficiência , Gônadas/anormalidades , Gônadas/patologia , Humanos , Hipogonadismo/genética , Hipogonadismo/metabolismo , Hipogonadismo/patologia , Hipogonadismo/fisiopatologia , Lactente , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Neurogênese/fisiologia , Neurônios/metabolismo , Transtornos do Olfato/genética , Transtornos do Olfato/metabolismo , Transtornos do Olfato/fisiopatologia , Condutos Olfatórios/metabolismo , Condutos Olfatórios/patologia , Tamanho do Órgão , Adulto Jovem
5.
Genet Med ; 22(3): 598-609, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31700164

RESUMO

PURPOSE: Most classical aniridia is caused by PAX6 haploinsufficiency. PAX6 missense variants can be hypomorphic or mimic haploinsufficiency. We hypothesized that missense variants also cause previously undescribed disease by altering the affinity and/or specificity of PAX6 genomic interactions. METHODS: We screened PAX6 in 372 individuals with bilateral microphthalmia, anophthalmia, or coloboma (MAC) from the Medical Research Council Human Genetics Unit eye malformation cohort (HGUeye) and reviewed data from the Deciphering Developmental Disorders study. We performed cluster analysis on PAX6-associated ocular phenotypes by variant type and molecular modeling of the structural impact of 86 different PAX6 causative missense variants. RESULTS: Eight different PAX6 missense variants were identified in 17 individuals (15 families) with MAC, accounting for 4% (15/372) of our cohort. Seven altered the paired domain (p.[Arg26Gln]x1, p.[Gly36Val]x1, p.[Arg38Trp]x2, p.[Arg38Gln]x1, p.[Gly51Arg]x2, p.[Ser54Arg]x2, p.[Asn124Lys]x5) and one the homeodomain (p.[Asn260Tyr]x1). p.Ser54Arg and p.Asn124Lys were exclusively associated with severe bilateral microphthalmia. MAC-associated variants were predicted to alter but not ablate DNA interaction, consistent with the electrophoretic mobility shifts observed using mutant paired domains with well-characterized PAX6-binding sites. We found no strong evidence for novel PAX6-associated extraocular disease. CONCLUSION: Altering the affinity and specificity of PAX6-binding genome-wide provides a plausible mechanism for the worse-than-null effects of MAC-associated missense variants.


Assuntos
Anormalidades do Olho/genética , Predisposição Genética para Doença , Microftalmia/genética , Fator de Transcrição PAX6/genética , Adolescente , Adulto , Sítios de Ligação/genética , Criança , Pré-Escolar , Estudos de Coortes , Proteínas de Ligação a DNA/genética , Anormalidades do Olho/patologia , Feminino , Heterozigoto , Humanos , Lactente , Masculino , Microftalmia/patologia , Mutação de Sentido Incorreto/genética , Linhagem , Adulto Jovem
6.
J Med Genet ; 56(7): 444-452, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30842225

RESUMO

BACKGROUND: A single variant in NAA10 (c.471+2T>A), the gene encoding N-acetyltransferase 10, has been associated with Lenz microphthalmia syndrome. In this study, we aimed to identify causative variants in families with syndromic X-linked microphthalmia. METHODS: Three families, including 15 affected individuals with syndromic X-linked microphthalmia, underwent analyses including linkage analysis, exome sequencing and targeted gene sequencing. The consequences of two identified variants in NAA10 were evaluated using quantitative PCR and RNAseq. RESULTS: Genetic linkage analysis in family 1 supported a candidate region on Xq27-q28, which included NAA10. Exome sequencing identified a hemizygous NAA10 polyadenylation signal (PAS) variant, chrX:153,195,397T>C, c.*43A>G, which segregated with the disease. Targeted sequencing of affected males from families 2 and 3 identified distinct NAA10 PAS variants, chrX:g.153,195,401T>C, c.*39A>G and chrX:g.153,195,400T>C, c.*40A>G. All three variants were absent from gnomAD. Quantitative PCR and RNAseq showed reduced NAA10 mRNA levels and abnormal 3' UTRs in affected individuals. Targeted sequencing of NAA10 in 376 additional affected individuals failed to identify variants in the PAS. CONCLUSION: These data show that PAS variants are the most common variant type in NAA10-associated syndromic microphthalmia, suggesting reduced RNA is the molecular mechanism by which these alterations cause microphthalmia/anophthalmia. We reviewed recognised variants in PAS associated with Mendelian disorders and identified only 23 others, indicating that NAA10 harbours more than 10% of all known PAS variants. We hypothesise that PAS in other genes harbour unrecognised pathogenic variants associated with Mendelian disorders. The systematic interrogation of PAS could improve genetic testing yields.


Assuntos
Regiões 3' não Traduzidas , Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Acetiltransferase N-Terminal A/genética , Acetiltransferase N-Terminal E/genética , Poli A , Alelos , Anoftalmia , Feminino , Genes Ligados ao Cromossomo X , Genótipo , Humanos , Escore Lod , Masculino , Microftalmia , Linhagem , Análise de Sequência de DNA , Inativação do Cromossomo X
7.
Retina ; 39(5): 948-955, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-29346240

RESUMO

PURPOSE: To determine the treatment effect of oral acetazolamide on refractory inflammatory macular edema. METHODS: A retrospective review of identified patients with uveitic or pseudophakic macular edema treated using acetazolamide between 2007 and 2014. Visual acuity and central macular subfield thickness was determined at baseline and at first follow-up. Baseline optical coherence tomography features were analyzed as predictors of acetazolamide response. RESULTS: Sixteen patients (19 eyes) of 61 screened met all criteria. Mean age was 57.9 years (19.7-81.1). The most common diagnosis was idiopathic uveitis (n = 6, 31.6%). Mean uveitis duration was 4.4 years (0.2-27.5). Average central macular subfield thickness decreased significantly (from 471.8 ± 110.6 µm to 358.3 ± 50.4 µm) (P < 0.0001). Average visual acuity (logarithm of the minimum angle of resolution) improved significantly from 20/54 (0.43 ± 0.25) to 20/37 (0.27 ± 0.16) (P = 0.003). Pretreatment optical coherence tomographies demonstrated intraretinal fluid (n = 19, 100%), subretinal fluid (n = 8, 42.1%), epiretinal membrane (n = 13, 68.3%), and vitreomacular traction (n = 1, 5.2%). No optical coherence tomography characteristic was predictive of a response to therapy. CONCLUSION: There is a significant benefit to vision and central macular subfield thickness after acetazolamide treatment in patients with inflammatory macular edema. In patients with refractory inflammatory macular edema, treatment using acetazolamide can provide anatomical and visual benefit without corticosteroid-related adverse effects.


Assuntos
Acetazolamida/administração & dosagem , Macula Lutea/patologia , Edema Macular/tratamento farmacológico , Acuidade Visual , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Anidrase Carbônica/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Angiofluoresceinografia , Fundo de Olho , Humanos , Edema Macular/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia de Coerência Óptica , Resultado do Tratamento , Adulto Jovem
8.
Hum Genet ; 138(8-9): 881-898, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30242502

RESUMO

Absence of part or all of the iris, aniridia, is a feature of several genetically distinct conditions. This review focuses on iris development and then the clinical features and molecular genetics of these iris malformations. Classical aniridia, a panocular eye malformation including foveal hypoplasia, is the archetypal phenotype associated with heterozygous PAX6 loss-of-function mutations. Since this was identified in 1991, many genetic mechanisms of PAX6 inactivation have been elucidated, the commonest alleles being intragenic mutations causing premature stop codons, followed by those causing C-terminal extensions. Rarely, aniridia cases are associated with FOXC1, PITX2 and/or their regulatory regions. Aniridia can also occur as a component of many severe global eye malformations. Gillespie syndrome-a triad of partial aniridia, non-progressive cerebellar ataxia and intellectual disability-is phenotypically and genotypically distinct from classical aniridia. The causative gene has recently been identified as ITPR1. The same characteristic Gillespie syndrome-like iris, with aplasia of the pupillary sphincter and a scalloped margin, is seen in ACTA2-related multisystemic smooth muscle dysfunction syndrome. WAGR syndrome (Wilms tumour, aniridia, genitourinary anomalies and mental retardation/intellectual disability), is caused by contiguous deletion of PAX6 and WT1 on chromosome 11p. Deletions encompassing BDNF have been causally implicated in the obesity and intellectual disability associated with the condition. Lastly, we outline a genetic investigation strategy for aniridia in light of recent developments, suggesting an approach based principally on chromosomal array and gene panel testing. This strategy aims to test all known aniridia loci-including the rarer, life-limiting causes-whilst remaining simple and practical.


Assuntos
Aniridia/genética , Ataxia Cerebelar/genética , Deficiência Intelectual/genética , Animais , Proteínas do Olho/genética , Humanos , Iris/patologia , Mutação/genética
9.
BMC Pediatr ; 18(1): 308, 2018 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-30249237

RESUMO

BACKGROUND: Gillespie syndrome is a rare, congenital, neurological disorder characterized by the association of partial bilateral aniridia, non-progressive cerebellar ataxia and intellectual disability. Homozygous and heterozygous pathogenic variants of the ITPR1 gene encoding an inositol 1, 4, 5- triphosphate- responsive calcium channel have been identified in 13 patients recently. There have been 22 cases reported in the literature by 2016, mostly from the western hemisphere with none reported from Sri Lanka. CASE PRESENTATION: A 10-year-old girl born to healthy non-consanguineous parents with delayed development is described. She started walking unaided by 9 years with a significantly unsteady gait and her speech was similarly delayed. Physical examination revealed multiple cerebellar signs. Slit lamp examination of eyes revealed bilateral partial aniridia. Magnetic resonance imaging of brain at the age of 10 years revealed cerebellar (mainly vermian) hypoplasia. Genetic testing confirmed the clinical suspicion and demonstrated a heterozygous pathogenic variant c.7786_7788delAAG p.(Lys2596del) in the ITPR1 gene. CONCLUSION: The report of this child with molecular confirmation of Gillespie syndrome highlights the need for careful evaluation of ophthalmological and neurological features in patients that enables correct clinical diagnosis. The availability of genetic testing enables more accurate counseling of the parents and patients regarding recurrence risks to other family members.


Assuntos
Aniridia/genética , Ataxia Cerebelar/genética , Heterozigoto , Receptores de Inositol 1,4,5-Trifosfato/genética , Deficiência Intelectual/genética , Mutação , Aniridia/diagnóstico , Aniridia/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Ataxia Cerebelar/diagnóstico , Ataxia Cerebelar/diagnóstico por imagem , Criança , Feminino , Humanos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/diagnóstico por imagem , Imageamento por Ressonância Magnética , Sri Lanka
10.
Comput Inform Nurs ; 36(2): 70-76, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29084028

RESUMO

Technology is an integral part of a nurse's practice; therefore, it is necessary for technology to be integrated into the nursing curriculum for students. Nursing schools are shifting paradigms by integrating technology into the teaching environment to foster active and meaningful learning experiences. Factors related to external influences on individual beliefs, attitudes, and intention to use need to be studied so nurse educators can support the integration of technology into pedagogy. The Technology Acceptance Model was used to evaluate student perceptions of usefulness and ease of use of technology, while matriculated in a baccalaureate level nursing program. Quantitative and qualitative data were collected to uncover how nursing students (N = 375) perceived the usefulness and ease of use of technology while in nursing school. Almost every student (99.7%) owned a smartphone, and 95% were reasonably comfortable using various technologies. Selecting and incorporating technological tools to successfully support learning is essential to overcome challenges and support the innovative delivery of content and use of technology by students.


Assuntos
Bacharelado em Enfermagem/organização & administração , Estudantes de Enfermagem/psicologia , Tecnologia , Adolescente , Adulto , Currículo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa em Educação em Enfermagem , Estudantes de Enfermagem/estatística & dados numéricos , Adulto Jovem
11.
Hum Mutat ; 38(8): 942-946, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28493397

RESUMO

Ocular coloboma (OC) is a defect in optic fissure closure and is a common cause of severe congenital visual impairment. Bilateral OC is primarily genetically determined and shows marked locus heterogeneity. Whole-exome sequencing (WES) was used to analyze 12 trios (child affected with OC and both unaffected parents). This identified de novo mutations in 10 different genes in eight probands. Three of these genes encoded proteins associated with actin cytoskeleton dynamics: ACTG1, TWF1, and LCP1. Proband-only WES identified a second unrelated individual with isolated OC carrying the same ACTG1 allele, encoding p.(Pro70Leu). Both individuals have normal neurodevelopment with no extra-ocular signs of Baraitser-Winter syndrome. We found this mutant protein to be incapable of incorporation into F-actin. The LCP1 and TWF1 variants each resulted in only minor disturbance of actin interactions, and no further plausibly causative variants were identified in these genes on resequencing 380 unrelated individuals with OC.


Assuntos
Actinas/genética , Coloboma/etiologia , Coloboma/genética , Animais , Feminino , Humanos , Masculino , Camundongos , Proteínas dos Microfilamentos/genética , Mutação/genética , Proteínas Tirosina Quinases/genética
13.
Nat Genet ; 49(2): 238-248, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28067909

RESUMO

Arhinia, or absence of the nose, is a rare malformation of unknown etiology that is often accompanied by ocular and reproductive defects. Sequencing of 40 people with arhinia revealed that 84% of probands harbor a missense mutation localized to a constrained region of SMCHD1 encompassing the ATPase domain. SMCHD1 mutations cause facioscapulohumeral muscular dystrophy type 2 (FSHD2) via a trans-acting loss-of-function epigenetic mechanism. We discovered shared mutations and comparable DNA hypomethylation patterning between these distinct disorders. CRISPR/Cas9-mediated alteration of smchd1 in zebrafish yielded arhinia-relevant phenotypes. Transcriptome and protein analyses in arhinia probands and controls showed no differences in SMCHD1 mRNA or protein abundance but revealed regulatory changes in genes and pathways associated with craniofacial patterning. Mutations in SMCHD1 thus contribute to distinct phenotypic spectra, from craniofacial malformation and reproductive disorders to muscular dystrophy, which we speculate to be consistent with oligogenic mechanisms resulting in pleiotropic outcomes.


Assuntos
Atresia das Cóanas/genética , Proteínas Cromossômicas não Histona/genética , Predisposição Genética para Doença/genética , Microftalmia/genética , Distrofias Musculares/genética , Mutação/genética , Nariz/anormalidades , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Fenótipo
15.
PLoS One ; 11(4): e0153757, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27124303

RESUMO

We report molecular genetic analysis of 42 affected individuals referred with a diagnosis of aniridia who previously screened as negative for intragenic PAX6 mutations. Of these 42, the diagnoses were 31 individuals with aniridia and 11 individuals referred with a diagnosis of Gillespie syndrome (iris hypoplasia, ataxia and mild to moderate developmental delay). Array-based comparative genomic hybridization identified six whole gene deletions: four encompassing PAX6 and two encompassing FOXC1. Six deletions with plausible cis-regulatory effects were identified: five that were 3' (telomeric) to PAX6 and one within a gene desert 5' (telomeric) to PITX2. Sequence analysis of the FOXC1 and PITX2 coding regions identified two plausibly pathogenic de novo FOXC1 missense mutations (p.Pro79Thr and p.Leu101Pro). No intragenic mutations were detected in PITX2. FISH mapping in an individual with Gillespie-like syndrome with an apparently balanced X;11 reciprocal translocation revealed disruption of a gene at each breakpoint: ARHGAP6 on the X chromosome and PHF21A on chromosome 11. In the other individuals with Gillespie syndrome no mutations were identified in either of these genes, or in HCCS which lies close to the Xp breakpoint. Disruption of PHF21A has previously been implicated in the causation of intellectual disability (but not aniridia). Plausibly causative mutations were identified in 15 out of 42 individuals (12/32 aniridia; 3/11 Gillespie syndrome). Fourteen of these mutations presented in the known aniridia genes; PAX6, FOXC1 and PITX2. The large number of individuals in the cohort with no mutation identified suggests greater locus heterogeneity may exist in both isolated and syndromic aniridia than was previously appreciated.


Assuntos
Aniridia/genética , Ataxia Cerebelar/genética , Deficiência Intelectual/genética , Fator de Transcrição PAX6/genética , Cromossomos Humanos Par 11/genética , Cromossomos Humanos X/genética , Hibridização Genômica Comparativa/métodos , Feminino , Fatores de Transcrição Forkhead/genética , Proteínas Ativadoras de GTPase/genética , Testes Genéticos/métodos , Histona Desacetilases/genética , Proteínas de Homeodomínio/genética , Humanos , Masculino , Mutação/genética , Fatores de Transcrição/genética , Proteína Homeobox PITX2
16.
Am J Hum Genet ; 98(5): 981-992, 2016 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-27108798

RESUMO

Gillespie syndrome (GS) is characterized by bilateral iris hypoplasia, congenital hypotonia, non-progressive ataxia, and progressive cerebellar atrophy. Trio-based exome sequencing identified de novo mutations in ITPR1 in three unrelated individuals with GS recruited to the Deciphering Developmental Disorders study. Whole-exome or targeted sequence analysis identified plausible disease-causing ITPR1 mutations in 10/10 additional GS-affected individuals. These ultra-rare protein-altering variants affected only three residues in ITPR1: Glu2094 missense (one de novo, one co-segregating), Gly2539 missense (five de novo, one inheritance uncertain), and Lys2596 in-frame deletion (four de novo). No clinical or radiological differences were evident between individuals with different mutations. ITPR1 encodes an inositol 1,4,5-triphosphate-responsive calcium channel. The homo-tetrameric structure has been solved by cryoelectron microscopy. Using estimations of the degree of structural change induced by known recessive- and dominant-negative mutations in other disease-associated multimeric channels, we developed a generalizable computational approach to indicate the likely mutational mechanism. This analysis supports a dominant-negative mechanism for GS variants in ITPR1. In GS-derived lymphoblastoid cell lines (LCLs), the proportion of ITPR1-positive cells using immunofluorescence was significantly higher in mutant than control LCLs, consistent with an abnormality of nuclear calcium signaling feedback control. Super-resolution imaging supports the existence of an ITPR1-lined nucleoplasmic reticulum. Mice with Itpr1 heterozygous null mutations showed no major iris defects. Purkinje cells of the cerebellum appear to be the most sensitive to impaired ITPR1 function in humans. Iris hypoplasia is likely to result from either complete loss of ITPR1 activity or structure-specific disruption of multimeric interactions.


Assuntos
Aniridia/etiologia , Aniridia/patologia , Ataxia Cerebelar/etiologia , Ataxia Cerebelar/patologia , Genes Dominantes/genética , Receptores de Inositol 1,4,5-Trifosfato/genética , Deficiência Intelectual/etiologia , Deficiência Intelectual/patologia , Mutação/genética , Adolescente , Adulto , Animais , Células Cultivadas , Criança , Feminino , Humanos , Receptores de Inositol 1,4,5-Trifosfato/química , Linfócitos/metabolismo , Linfócitos/patologia , Masculino , Camundongos , Microscopia Confocal , Pessoa de Meia-Idade , Linhagem , Conformação Proteica
17.
Hum Mol Genet ; 25(7): 1382-91, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26908622

RESUMO

Ocular coloboma is a common eye malformation resulting from incomplete fusion of the optic fissure during development. Coloboma is often associated with microphthalmia and/or contralateral anophthalmia. Coloboma shows extensive locus heterogeneity associated with causative mutations identified in genes encoding developmental transcription factors or components of signaling pathways. We report an ultra-rare, heterozygous frameshift mutation in FZD5 (p.Ala219Glufs*49) that was identified independently in two branches of a large family with autosomal dominant non-syndromic coloboma. FZD5 has a single-coding exon and consequently a transcript with this frameshift variant is not a canonical substrate for nonsense-mediated decay. FZD5 encodes a transmembrane receptor with a conserved extracellular cysteine rich domain for ligand binding. The frameshift mutation results in the production of a truncated protein, which retains the Wingless-type MMTV integration site family member-ligand-binding domain, but lacks the transmembrane domain. The truncated protein was secreted from cells, and behaved as a dominant-negative FZD5 receptor, antagonizing both canonical and non-canonical WNT signaling. Expression of the resultant mutant protein caused coloboma and microphthalmia in zebrafish, and disruption of the apical junction of the retinal neural epithelium in mouse, mimicking the phenotype of Fz5/Fz8 compound conditional knockout mutants. Our studies have revealed a conserved role of Wnt-Frizzled (FZD) signaling in ocular development and directly implicate WNT-FZD signaling both in normal closure of the human optic fissure and pathogenesis of coloboma.


Assuntos
Mutação da Fase de Leitura , Receptores Frizzled/genética , Via de Sinalização Wnt , Animais , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Camundongos , Microftalmia/genética , Microftalmia/metabolismo , Linhagem , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
18.
BMC Pulm Med ; 16: 25, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26846438

RESUMO

BACKGROUND: Oxygen desaturation during exercise is common in people with chronic obstructive pulmonary disease (COPD). The aim of the study is to determine, in people with COPD who desaturate during exercise, whether supplemental oxygen during an eight-week exercise training program is more effective than medical air (sham intervention) in improving exercise capacity and health-related quality of life both at the completion of training and at six-month follow up. METHODS/DESIGN: This is a multi-centre randomised controlled trial with concealed allocation, blinding of participants, exercise trainers and assessors, and intention-to-treat analysis. 110 people with chronic obstructive pulmonary disease who demonstrate oxygen desaturation lower than 90 % during the six-minute walk test will be recruited from pulmonary rehabilitation programs in seven teaching hospitals in Australia. People with chronic obstructive pulmonary disease on long term oxygen therapy will be excluded. After confirmation of eligibility and baseline assessment, participants will be randomised to receive either supplemental oxygen or medical air during an eight-week supervised treadmill and cycle exercise training program, three times per week for eight weeks, in hospital outpatient settings. Primary outcome measures will be endurance walking capacity assessed by the endurance shuttle walk test and health-related quality of life assessed by the Chronic Respiratory Disease Questionnaire. Secondary outcomes will include peak walking capacity measured by the incremental shuttle walk test, dyspnoea via the Dyspnoea-12 questionnaire and physical activity levels measured over seven days using an activity monitor. All outcomes will be measured at baseline, completion of training and at six-month follow up. DISCUSSION: Exercise training is an essential component of pulmonary rehabilitation for people with COPD. This study will determine whether supplemental oxygen during exercise training is more effective than medical air in improving exercise capacity and health-related quality of life in people with COPD who desaturate during exercise. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12612000395831, 5th Jan,2012.


Assuntos
Terapia por Exercício/métodos , Oxigenoterapia/métodos , Doença Pulmonar Obstrutiva Crônica/reabilitação , Austrália , Método Duplo-Cego , Dispneia/fisiopatologia , Teste de Esforço , Tolerância ao Exercício/fisiologia , Volume Expiratório Forçado , Nível de Saúde , Humanos , Análise de Intenção de Tratamento , Oximetria , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Qualidade de Vida , Resultado do Tratamento , Capacidade Vital
19.
J Nurses Prof Dev ; 31(2): 73-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25790357

RESUMO

This collaborative study explored nurses' knowledge, attitudes, and skills related to the evidence-based practice (EBP) process. It also explored the nurses' perceptions of the barriers and facilitators that they face related to fully using EBP in the workplace. Findings will afford the healthcare system the information to develop, plan, and restructure the educational services to meet the demand of enhancing EBP strategies and utilization.


Assuntos
Prática Clínica Baseada em Evidências , Conhecimentos, Atitudes e Prática em Saúde , Recursos Humanos de Enfermagem Hospitalar , Desenvolvimento de Programas , Difusão de Inovações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros , Desenvolvimento de Pessoal , Inquéritos e Questionários
20.
Nurse Educ Today ; 35(1): 80-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25027871

RESUMO

BACKGROUND: Competency in evidence-based practice (EBP) is a requirement for graduate nurses. Despite a growing body of research exploring the EBP profiles of students, little research has explored the EBP profiles of nurse educators. OBJECTIVES: To explore: the differences/similarities in the EBP profiles of US and UK clinical and academic faculty; the barriers nurse educators experience when teaching EBP; the impact of postgraduate education on EBP profile and; what nurse educators perceive "success" in implementing and teaching EBP to be. DESIGN: A cross-sectional online survey design was employed. SETTINGS: Two Universities delivering undergraduate nursing education in the US and UK, in partnership with large hospital systems, small community hospitals, community settings, and independent sector health organisations. PARTICIPANTS: Eighty-one nurse educators working in academic and clinical contexts in the US and UK (US academic=12, US clinical=17, UK academic=9, UK clinical=43) were recruited opportunistically. METHODS: Participants were emailed a weblink to an online survey, comprising demographic questions, the Evidence-Based Practice Questionnaire and open-ended questions about EBP barriers, facilitators and successes. RESULTS: Quantitative results indicated that academic faculty scored significantly higher on knowledge and skills of EBP, than clinical faculty, but revealed no other significant differences on EBP use or attitudes, or between US and UK professionals. Participants with postgraduate training scored significantly higher on EBP knowledge/skills, but not EBP attitudes or use. Qualitative findings identified key themes relating to EBP barriers and facilitators, including: Evidence-, organisational-, and teaching-related issues. Perceptions of successes in EBP were also described. CONCLUSIONS: Nurse educators working in the UK and US face similar EBP barriers to teaching and implementation, but view it positively and use it frequently. Clinical staff may require extra support to maintain their EBP knowledge and skills in comparison to staff working in academic contexts.


Assuntos
Educação de Pós-Graduação em Enfermagem , Enfermagem Baseada em Evidências/educação , Docentes de Enfermagem , Estudantes de Enfermagem , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Ensino/métodos , Reino Unido , Estados Unidos
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