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1.
BMC Ophthalmol ; 23(1): 438, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37904082

RESUMO

BACKGROUND: To investigate the efficacy and safety of 0.1% and 0.01% low-dose atropine eye drops in reducing myopia progression in Danish children. METHODS: Investigator-initiated, placebo-controlled, double-masked, randomized clinical trial. Ninety-seven six- to twelve-year old myopic participants were randomized to 0.1% loading dose for six months followed by 0.01% for six months (loading dose group, Number (N) = 33), 0.01% for twelve months (0.01% group, N = 32) or vehicle for twelve months (placebo, N = 32). Primary outcomes were axial length and spherical equivalent refraction. Secondary outcomes included adverse events and reactions, choroidal thickness and ocular biometry. Outcomes were measured at baseline and three-month intervals. Data was analyzed with linear-mixed model analysis according to intention-to-treat. RESULTS: Mean axial elongation was 0.10 mm less (95% confidence interval (CI): 0.17; 0.02, adjusted-p = 0.06) in the 0.1% loading dose and 0.07 mm less (95% CI: 0.15; 0.00, adjusted-p = 0.16) in the 0.01% group at twelve months compared to placebo. Mean spherical equivalent refraction progression was 0.24 D (95% CI: 0.05; 0.42) less in the loading dose and 0.19 D (95% CI: 0.00; 0.38) less in the 0.01% groups at twelve months, compared to placebo (adjusted-p = 0.06 and 0.14, respectively). A total of 108 adverse events were reported during the initial six-month loading dose period, primarily in the loading dose group, and 14 were reported in the six months following dose switching, all deemed mild except two serious adverse events, unrelated to the intervention. CONCLUSIONS: Low-dose atropine eye drops are safe over twelve months in otherwise healthy children. There may be a modest but clinically relevant reduction in myopia progression in Danish children after twelve months treatment, but the effect was statistically non-significant after multiple comparisons adjustment. After dose-switching at six months the loading dose group approached the 0.01% group, potentially indicating an early "rebound-effect". TRIAL REGISTRATION: this study was registered in the European Clinical Trials Database (EudraCT, number: 2018-001286-16) 05/11/2018 and first posted at www. CLINICALTRIALS: gov (NCT03911271) 11/04/2019, prior to initiation.


Assuntos
Atropina , Miopia , Criança , Humanos , Atropina/uso terapêutico , Soluções Oftálmicas , Miopia/tratamento farmacológico , Refração Ocular , Dinamarca , Progressão da Doença , Comprimento Axial do Olho
2.
Hum Genet ; 140(12): 1709-1731, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34652576

RESUMO

Microtubules are formed from heterodimers of alpha- and beta-tubulin, each of which has multiple isoforms encoded by separate genes. Pathogenic missense variants in multiple different tubulin isoforms cause brain malformations. Missense mutations in TUBB3, which encodes the neuron-specific beta-tubulin isotype, can cause congenital fibrosis of the extraocular muscles type 3 (CFEOM3) and/or malformations of cortical development, with distinct genotype-phenotype correlations. Here, we report fourteen individuals from thirteen unrelated families, each of whom harbors the identical NM_006086.4 (TUBB3):c.785G>A (p.Arg262His) variant resulting in a phenotype we refer to as the TUBB3 R262H syndrome. The affected individuals present at birth with ptosis, ophthalmoplegia, exotropia, facial weakness, facial dysmorphisms, and, in most cases, distal congenital joint contractures, and subsequently develop intellectual disabilities, gait disorders with proximal joint contractures, Kallmann syndrome (hypogonadotropic hypogonadism and anosmia), and a progressive peripheral neuropathy during the first decade of life. Subsets may also have vocal cord paralysis, auditory dysfunction, cyclic vomiting, and/or tachycardia at rest. All fourteen subjects share a recognizable set of brain malformations, including hypoplasia of the corpus callosum and anterior commissure, basal ganglia malformations, absent olfactory bulbs and sulci, and subtle cerebellar malformations. While similar, individuals with the TUBB3 R262H syndrome can be distinguished from individuals with the TUBB3 E410K syndrome by the presence of congenital and acquired joint contractures, an earlier onset peripheral neuropathy, impaired gait, and basal ganglia malformations.


Assuntos
Paralisia Facial/genética , Fibrose/genética , Mutação , Oftalmoplegia/genética , Doenças do Sistema Nervoso Periférico/genética , Tubulina (Proteína)/genética , Anormalidades Múltiplas/genética , Adolescente , Adulto , Substituição de Aminoácidos , Arginina , Criança , Pré-Escolar , Paralisia Facial/diagnóstico , Paralisia Facial/fisiopatologia , Feminino , Fibrose/diagnóstico , Fibrose/fisiopatologia , Histidina , Humanos , Lactente , Masculino , Oftalmoplegia/diagnóstico , Oftalmoplegia/fisiopatologia , Doenças do Sistema Nervoso Periférico/diagnóstico , Doenças do Sistema Nervoso Periférico/fisiopatologia , Síndrome , Adulto Jovem
3.
Ophthalmic Res ; 58(3): 142-149, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28683455

RESUMO

PURPOSE: Treatment of diabetic maculopathy with vascular endothelial growth factor inhibitors is in some patients ineffective, and, therefore, parameters predicting visual outcome after treatment should be identified. It has been shown that fixational saccades are increased in patients with reduced visual acuity secondary to diabetic maculopathy, but it is unknown to what extent these saccades in an eye affected by diabetic maculopathy are influenced by the other eye during binocular fixation. METHODS: In 57 eyes from 29 diabetic patients with clinically significant macular edema, fixational eye movements were recorded using the iView X™ video-based eye tracker, and quantitative measures of fixation with the worst eye obtained during monocular and binocular fixation were compared. RESULTS: Fixational saccades during monocular fixation had a significantly higher frequency (p = 0.005), a larger amplitude (p = 0.03), and involved a larger retinal area (p = 0.02) than during binocular fixation. There was a significant negative correlation (r2 = 0.18, p = 0.02) between visual acuity and the area of fixation during monocular but not during binocular fixation (r2 = 0.007, p = 0.68). CONCLUSION: Binocular fixation can reduce the area of fixation and the amplitude of fixational saccades in the worst eye of patients with diabetic maculopathy. Fixational saccades in diabetic maculopathy should be studied during monocular fixation.


Assuntos
Retinopatia Diabética/fisiopatologia , Movimentos Oculares/fisiologia , Fixação Ocular/fisiologia , Edema Macular/fisiopatologia , Visão Binocular/fisiologia , Acuidade Visual , Estudos Transversais , Retinopatia Diabética/complicações , Feminino , Seguimentos , Humanos , Edema Macular/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
4.
J Clin Nurs ; 26(9-10): 1363-1374, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27648554

RESUMO

AIMS AND OBJECTIVES: To explore and describe how young adults between 18-25 years of age experienced growing up with a parent with multiple sclerosis and how these experiences continue to influence their daily lives. BACKGROUND: Chronic parental illness is occurring in about 10% of families worldwide, but little is known about how the children experience growing up with a parent with multiple sclerosis during their childhood and into young adulthood. DESIGN: We chose a qualitative design using a phenomenological approach based on Giorgi. METHODS: Exploratory and open-ended interviews with 14 young adults were conducted. RESULTS: The essence of the phenomenon of having a parent with multiple sclerosis was synthesized into 'Striving for balance between caring and restraint' from two themes 'caring' and 'restraint' and eight subthemes. Participants' experiences of caring for parents with multiple sclerosis continued influencing their other close relationships, in which they tended to assume responsibility while concealing some of their feelings and desires. Most participants showed restraint among parents with and without multiple sclerosis, friends and partners. CONCLUSION: It seems that one of the greatest challenges of having a parent with multiple sclerosis is achieving a balance between caring for others and asserting one's own desires. RELEVANCE TO CLINICAL PRACTICE: Healthcare professionals can support the family by encouraging family members to participate in consultations and to assist the parents in providing information about multiple sclerosis and its symptoms to the children. Parents might need assistance in applying for help with domestic chores or referrals to support groups for their children or other family members.


Assuntos
Cuidadores/psicologia , Filho de Pais com Deficiência/psicologia , Esclerose Múltipla/psicologia , Autoimagem , Atividades Cotidianas , Adaptação Psicológica , Adulto , Emoções , Empatia , Feminino , Humanos , Masculino , Relações Pais-Filho , Adulto Jovem
5.
Appl Microbiol Biotechnol ; 99(10): 4245-53, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25434812

RESUMO

Enzymatic conversion of pectinaceous biomasses such as potato and sugar beet pulp at high temperatures is advantageous as it gives rise to lower substrate viscosity, easier mixing, and increased substrate solubility and lowers the risk of contamination. Such high-temperature processing requires development of thermostable enzymes. Talaromyces stipitatus was found to secrete endo-1,4-ß-galactanase when grown on sugar beet pectin as sole carbon source. The mature protein contained 353 AA and the MW was estimated to 36.5 kDa. It was subjected to codon optimization and produced in Pichia pastoris in 2 l scale yielding 5.3 g. The optimal reaction condition for the endo-1,4-ß-galactanase was determined to be 46 °C at pH 4.5 at which the specific activity was estimated to be 6.93 µmol/min/mg enzyme with half-lives of 13 and 2 min at 55 and 60 °C, respectively. For enhancement of the half-life of TSGAL, nine single amino acid residues were selected for site-directed mutagenesis on the basis of semi-rational design. Of these nine mutants, G305A showed half-lives of 114 min at 55 °C and 15 min at 60 °C, respectively. This is 8.6-fold higher than that of the TSGAL at 55 °C, whereas the other mutants displayed moderate positive to negative changes in their half-lives.


Assuntos
Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/genética , Talaromyces/enzimologia , Sequência de Aminoácidos , Clonagem Molecular , Estabilidade Enzimática , Proteínas Fúngicas/metabolismo , Glicosídeo Hidrolases/metabolismo , Temperatura Alta , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Pichia/genética , Pichia/metabolismo , Engenharia de Proteínas , Especificidade por Substrato , Talaromyces/química , Talaromyces/genética
6.
Appl Microbiol Biotechnol ; 98(10): 4521-31, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24419797

RESUMO

Rhamnogalacturonan I lyases (RGI lyases) (EC 4.2.2.-) catalyze cleavage of α-1,4 bonds between rhamnose and galacturonic acid in the backbone of pectins by ß-elimination. In the present study, targeted improvement of the thermostability of a PL family 11 RGI lyase from Bacillus licheniformis (DSM 13/ATCC14580) was examined by using a combinatorial protein engineering approach exploring additive effects of single amino acid substitutions. These were selected by using a consensus approach together with assessing protein stability changes (PoPMuSiC) and B-factor iterative test (B-FIT). The second-generation mutants involved combinations of two to seven individually favorable single mutations. Thermal stability was examined as half-life at 60 °C and by recording of thermal transitions by circular dichroism. Surprisingly, the biggest increment in thermal stability was achieved by producing the wild-type RGI lyase in Bacillus subtilis as opposed to in Pichia pastoris; this effect is suggested to be a negative result of glycosylation of the P. pastoris expressed enzyme. A ~ twofold improvement in thermal stability at 60 °C, accompanied by less significant increases in T m of the enzyme mutants, were obtained due to additive stabilizing effects of single amino acid mutations (E434L, G55V, and G326E) compared to the wild type. The crystal structure of the B. licheniformis wild-type RGI lyase was also determined; the structural analysis corroborated that especially mutation of charged amino acids to hydrophobic ones in surface-exposed loops produced favorable thermal stability effects.


Assuntos
Bacillus/enzimologia , Pectinas/metabolismo , Mutação Puntual , Polissacarídeo-Liases/química , Polissacarídeo-Liases/metabolismo , Substituição de Aminoácidos , Bacillus/genética , Dicroísmo Circular , Estabilidade Enzimática/efeitos da radiação , Temperatura Alta , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Pichia/enzimologia , Pichia/genética , Polissacarídeo-Liases/genética , Conformação Proteica , Engenharia de Proteínas , Estabilidade Proteica/efeitos da radiação
7.
Acta Ophthalmol ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39132692

RESUMO

PURPOSE: Treatment with glucocorticoids following paediatric cataract surgery is crucial to prevent inflammation, but may lead to secondary glaucoma, and hypothalamic-pituitary-adrenal axis suppression. We wish to compare glaucoma outcomes following high-dose and low-dose glucocorticoid treatment after paediatric cataract surgery. METHODS: This cohort study included Danish children undergoing cataract surgery before 10 years of age, receiving either a low-dose or high-dose postoperative glucocorticoid treatment. Case identification and collection of a standardized dataset were retrospective, from 1 January 2010 to 31 December 2016, and prospective thereafter, until 31 December 2021. High-dose treatment included 0.5-1.0 mg subconjunctival depot dexamethasone or methylprednisolone, followed by 6-8 drops of dexamethasone for 1 week, tapered by one drop weekly. Low-dose treatment included 6 drops for 3 days, followed by 3 drops for 18 days. Sustained (>3 months) ocular hypertension or glaucoma was compared between the two groups. RESULTS: Overall, 267 children (388 eyes) were included in the study. Ninety-five children (133 eyes) had received high-dose treatment and had a median follow-up time of 89 months (IQR: 57.2-107.4), while 173 children (255 eyes) had received the low-dose treatment and had a median follow-up time of 40.5 months (IQR: 22.9-60.4). Survival curves showed a lower risk of glaucoma in the low-dose group for children with axial lengths ≥18 mm. CONCLUSION: Low-dose glucocorticoid treatment was associated with a lower risk of glaucoma in children with axial lengths ≥18 mm. The same effect was not observed in children with shorter eyes. High-dose glucocorticoid should be limited in children undergoing cataract surgery.

8.
J Pers Med ; 14(2)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38392608

RESUMO

We investigated the two-year safety and efficacy of 0.1% loading dose and 0.01% low-dose atropine eye drops in Danish children for reduction in myopia progression in an investigator-initiated, placebo-controlled, double-masked, randomized clinical trial. Ninety-seven six- to twelve-year old myopic participants were randomized to 0.1% loading dose for six months and then 0.01% for eighteen months (loading dose group, N = 33), 0.01% for two years (0.01% group, N = 32) or placebo for two years (placebo, N = 32). Axial length (AL) and spherical equivalent refraction (SER) were primary outcomes. Secondary outcomes included adverse events and reactions, choroidal thickness, and other ocular biometrical measures. Outcomes were measured from baseline and at six-month intervals. Individual eyes nested by participant ID were analyzed with linear-mixed model analysis. Data were analyzed with intention-to-treat. Mean AL was 0.08 mm less (95% confidence interval (CI): -0.01; 0.17, p-value = 0.08) in the 0.1% loading dose and 0.10 mm less (95% CI: 0.01; 0.19, p-value = 0.02) in the 0.01% group after two years of treatment compared to placebo. Mean SER progression was 0.12 D (95% CI: -0.10; 0.33) less in the loading dose and 0.26 D (95% CI: 0.04; 0.48) less in the 0.01% groups after two years of treatment compared to placebo (p-value = 0.30 and 0.02, respectively). In total, 17 adverse events were reported in the second-year follow-up, and all were rated as mild. Adjusting for iris color did not affect treatment effect estimates. Intra-ocular pressure increased over two years comparably between all groups but remained within normal limits. Two-year treatment with 0.01% low-dose atropine eye drops is a safe and moderately efficacious intervention in Danish children for reducing myopia progression.

9.
Appl Microbiol Biotechnol ; 97(22): 9727-35, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23995225

RESUMO

Rhamnogalacturonan I lyase (RGI lyase) (EC 4.2.2.-) catalyzes the cleavage of rhamnogalacturonan I in pectins by ß-elimination. In this study the thermal stability of a RGI lyase (PL 11) originating from Bacillus licheniformis DSM 13/ATCC14580 was increased by a targeted protein engineering approach involving single amino acid substitution. Nine individual amino acids were selected as targets for site-saturated mutagenesis by the use of a predictive consensus approach in combination with prediction of protein mutant stability changes and B-factor iteration testing. After extensive experimental verification of the thermal stability of the designed mutants versus the original wild-type RGI lyase, several promising single point mutations were obtained, particularly in position Glu434 on the surface of the enzyme protein. The best mutant, Glu434Leu, produced a half-life of 31 min at 60 °C, corresponding to a 1.6-fold improvement of the thermal stability compared to the original RGI lyase. Gly55Val was the second best mutation with a thermostability half-life increase of 27 min at 60 °C, and the best mutations following were Glu434Trp, Glu434Phe, and Glu434Tyr, respectively. The data verify the applicability of a combinatorial predictive approach for designing a small site saturation library for improving enzyme thermostability. In addition, new thermostable RGI lyases suitable for enzymatic upgrading of pectinaceous plant biomass materials at elevated temperatures were produced.


Assuntos
Bacillus/enzimologia , Pectinas/metabolismo , Polissacarídeo-Liases/genética , Polissacarídeo-Liases/metabolismo , Bacillus/genética , Análise Mutacional de DNA , DNA Bacteriano/química , DNA Bacteriano/genética , Estabilidade Enzimática , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutação Puntual , Polissacarídeo-Liases/química , Estabilidade Proteica , Análise de Sequência de DNA , Temperatura
10.
Acta Ophthalmol ; 101(2): 229-235, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36165330

RESUMO

PURPOSE: To examine the prevalence and risk factors for hypothalamus-pituitary-adrenal axis suppression (HPA axis suppression) in infants receiving glucocorticoid (GC) eye drops after ocular surgery. METHODS: This was a clinical observational cohort study. Children under the age of two receiving GC eye drops after cataract or glaucoma surgery between 1 January 2017 and 31 December 2021 were included at one centre. Medical history and results of the adrenocorticotropic hormone (ACTH) stimulation tests were obtained through patient charts. RESULTS: Forty-nine infants were included in the study. Ten out of 22 patients (45.5%) tested during treatment and two out of 27 patients (7.4%) tested after treatment cessation were diagnosed with HPA axis suppression. The duration of HPA axis suppression extended beyond 3 months in 8 out of 12 patients. Logistic regression showed that infants with HPA axis suppression had received a higher GC dose/body weight/day before the first ACTH test (p < 0.001). There was a 79% (95% CI:1.28;2.50) increase in the odds of having HPA axis suppression for a 0.01 mg GC increase/kg/day corresponding to an additional daily eye drop for an infant weighing 5 kg. There was an association between HPA axis suppression and number of days from surgery to test (p = 0.003), age at surgery (p = 0.035) and cumulated GC dose (p = 0.005). Three infants with HPA axis suppression had affected growth and one had Cushing-like features, but there were no cases of Addisonian crisis. CONCLUSION: Infants are at risk of having hypothalamus-pituitary-adrenal axis suppression if they receive a high daily glucocorticoid dose per weight by topical ocular administration. Infants receiving glucocorticoids after ocular surgery should be monitored clinically or by ACTH testing.


Assuntos
Glucocorticoides , Sistema Hipotálamo-Hipofisário , Sistema Hipófise-Suprarrenal , Criança , Humanos , Lactente , Hormônio Adrenocorticotrópico , Glucocorticoides/efeitos adversos , Glucocorticoides/farmacologia , Glucocorticoides/uso terapêutico , Hidrocortisona , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipotálamo-Hipofisário/patologia , Soluções Oftálmicas , Oftalmologia , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/metabolismo , Sistema Hipófise-Suprarrenal/patologia , Prevalência , Fatores de Risco , Oftalmopatias/cirurgia
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