81 research outputs found

    Fractures around the shoulder in the skeletally immature:A scoping review

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    Fractures around the shoulder girdle in children are mainly caused by sports accidents. The clavicle and the proximal humerus are most commonly involved. Both the clavicle and the proximal humerus have a remarkable potential for remodeling, which is why most of these fractures in children can be treated conservatively. However, the key is to understand when a child benefits from surgical management. Clear indications for surgery of these fractures are lacking. This review focuses on the available evidence on the management of clavicle and proximal humerus fractures in children. The only strict indications for surgery for diaphyseal clavicle fractures in children are open fractures, tenting of the skin with necrosis, associated neurovascular injury, or a floating shoulder. There is no evidence to argue for surgery of displaced clavicle fractures to prevent malunion since most malunions are asymptomatic. In the rare case of a symptomatic malunion of the clavicle in children, corrective osteosynthesis is a viable treatment option. For proximal humerus fractures in children, treatment is dictated by the patient's age (and thus remodeling potential) and the amount of fracture displacement. Under ten years of age, even severely displaced fractures can be treated conservatively. From the age of 13 and onwards, surgery has better outcomes for severely displaced (Neer types III and IV) fractures. Between 10 and 13 years of age, the indications for surgical treatment are less clear, with varying cut-off values of angulation (30-60 degrees) or displacement (1/3 – 2/3 shaft width) in the current literature.</p

    The role of small molecules and their effect on the molecular mechanisms of early retinal organoid development

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    Early in vivo embryonic retinal development is a well-documented and evolutionary conserved process. The specification towards eye development is temporally controlled by consecutive activation or inhibition of multiple key signaling pathways, such as the Wnt and hedgehog signaling pathways. Recently, with the use of retinal organoids, researchers aim to manipulate these pathways to achieve better human representative models for retinal development and disease. To achieve this, a plethora of different small molecules and signaling factors have been used at various time points and concentrations in retinal organoid differentiations, with varying success. Additions differ from protocol to protocol, but their usefulness or efficiency has not yet been systematically reviewed. Interestingly, many of these small molecules affect the same and/or multiple pathways, leading to reduced reproducibility and high variability between studies. In this review, we make an inventory of the key signaling pathways involved in early retinogenesis and their effect on the development of the early retina in vitro. Further, we provide a comprehensive overview of the small molecules and signaling factors that are added to retinal organoid differentiation protocols, documenting the molecular and functional effects of these additions. Lastly, we comparatively evaluate several of these factors using our established retinal organoid methodology.Ophthalmic researc

    The LRAT(-/-) rat: CRISPR/Cas9 construction and phenotyping of a new animal model for retinitis pigmentosa

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    Purpose: We developed and phenotyped a pigmented knockout rat model for lecithin retinol acyltransferase (LRAT) using CRISPR/Cas9. The introduced mutation (c.12delA) is based on a patient group harboring a homologous homozygous frameshift mutation in the LRAT gene (c.12delC), causing a dysfunctional visual (retinoid) cycle. Methods: The introduced mutation was confirmed by DNA and RNA sequencing. The expression of Lrat was determined on both the RNA and protein level in wildtype and knockout animals using RT-PCR and immunohistochemistry. The retinal structure and function, as well as the visual behavior of the Lrat(-/-) and control rats, were characterized using scanning laser ophthalmoscopy (SLO), optical coherence tomography (OCT), electroretinography (ERG) and vision-based behavioral assays. Results: Wildtype animals had high Lrat mRNA expression in multiple tissues, including the eye and liver. In contrast, hardly any expression was detected in Lrat(-/-) animals. LRAT protein was abundantly present in wildtype animals and absent in Lrat(-/-) animals. Lrat(-/-) animals showed progressively reduced ERG potentials compared to wildtype controls from two weeks of age onwards. Vison-based behavioral assays confirmed reduced vision. Structural abnormalities, such as overall retinal thinning, were observed in Lrat(-/-) animals. The retinal thickness in knockout rats was decreased to roughly 80% by four months of age. No functional or structural differences were observed between wildtype and heterozygote animals. Conclusions: Our Lrat(-/-) rat is a new animal model for retinal dystrophy, especially for the LRAT-subtype of early-onset retinal dystrophies. This model has advantages over the existing mouse models and the RCS rat strain and can be used for translational studies of retinal dystrophies.Ophthalmic researc

    The phenotypic spectrum of patients with PHARC syndrome due to variants in ABHD12: an ophthalmic perspective

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    This study investigated the phenotypic spectrum of PHARC (polyneuropathy, hearing loss, ataxia, retinitis pigmentosa and early-onset cataract) syndrome caused by biallelic variants in the ABHD12 gene. A total of 15 patients from 12 different families were included, with a mean age of 36.7 years (standard deviation [SD] +/- 11.0; range from 17.5 to 53.9) at the most recent examination. The presence and onset of neurological, audiological and ophthalmic symptoms were variable, with no evident order of symptom appearance. The mean best-corrected visual acuity was 1.1 logMAR (SD +/- 0.9; range from 0.1 to 2.8; equivalent to 20/250 Snellen) and showed a trend of progressive decline. Different types of cataract were observed in 13 out of 15 patients (87%), which also included congenital forms of cataract. Fundus examination revealed macular involvement in all patients, ranging from alterations of the retinal pigment epithelium to macular atrophy. Intraretinal spicular hyperpigmentation was observed in 7 out of 15 patients (47%). From an ophthalmic perspective, clinical manifestations in patients with PHARC demonstrate variability with regard to their onset and severity. Given the variable nature of PHARC, an early multidisciplinary assessment is recommended to assess disease severity.Ophthalmic researc

    Long-Acting Injectable ART and PrEP Among Women in Six Cities Across the United States: A Qualitative Analysis of Who Would Benefit the Most

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    Long-acting injectable (LAI) modalities have been developed for ART and PrEP. Women face unique barriers to LAI use yet little research has examined women’s perceptions of potential LAI HIV therapy candidates. We conducted 89 in-depth interviews at six Women’s Interagency HIV Study (WIHS) sites with women living with HIV (n = 59) and HIV-negative women (n = 30) from 2017 to 2018. Interviews were recorded, transcribed, and analyzed using thematic content analysis. Participants identified specific sub-populations who could most benefit from LAI over daily pills: (1) young people; (2) women with childcare responsibilities; (3) people with adherence-related psychological distress; (4) individuals with multiple sex partners; and (5) people facing structural insecurities such as homelessness. Women are underserved by current HIV care options and their perspectives are imperative to ensure a successful scale-up of LAI PrEP and LAI ART that prioritizes equitable access and benefit for all individuals

    Design of the FemCure study: Prospective multicentre study on the transmission of genital and extra-genital Chlamydia trachomatis infections in women receiving routine care

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    Background: In women, anorectal infections with Chlamydia trachomatis (CT) are about as common as genital CT, yet the anorectal site remains largely untested in routine care. Anorectal CT frequently co-occurs with genital CT and may thus often be treated co-incidentally. Nevertheless, post-treatment detection of CT at both anatomic sites has been demonstrated. It is unknown whether anorectal CT may play a role in post-treatment transmission. This study, called FemCure, in women who receive routine treatment (either azithromycin or doxycycline) aims to understand the post-treatment transmission of anorectal CT infections, i.e., from their male sexual partner(s) and from and to the genital region of the same woman. The secondary objective is to evaluate other reasons for CT detection by nucleic acid amplification techniques (NAAT) such as treatment failure, in order to inform guidelines to optimize CT control. Methods: A multicentre prospective cohort study (FemCure) is set up in which genital and/or anorectal CT positive women (n=400) will be recruited at three large Dutch STI clinics located in South Limburg, Amsterdam and Rotterdam. The women self-collect anorectal and vaginal swabs before treatment, and at the end of weeks 1, 2, 4, 6, 8, 10, and 12. Samples are tested for presence of CT-DNA (by NAAT), load (by quantitative polymerase chain reaction -PCR), viability (by culture and viability PCR) and CT type (by multilocus sequence typing). Sexual exposure is assessed by online self-administered questionnaires and by testing samples for Y chromosomal DNA. Using logistic regression models, the impact of two key factors (i.e., sexual exposure and alternate anatomic site of infection) on detection of anorectal and genital CT will be assessed. Discussion: The FemCure study will provide insight in the role of anorectal chlamydia infection in maintaining the CT burden in the context of treatment, and it will provide practical recommendations to reduce avoidable transmission. Implications will improve care strategies that take account of anorectal CT

    The TREAT-NMD DMD Global Database: Analysis of more than 7,000 Duchenne Muscular Dystrophy mutations

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    Analyzing the type and frequency of patient-specific mutations that give rise to Duchenne muscular dystrophy (DMD) is an invaluable tool for diagnostics, basic scientific research, trial planning, and improved clinical care. Locus-specific databases allow for the collection, organization, storage, and analysis of genetic variants of disease. Here, we describe the development and analysis of the TREAT-NMD DMD Global database (http://umd.be/TREAT_DMD/). We analyzed genetic data for 7,149 DMD mutations held within the database. A total of 5,682 large mutations were observed (80% of total mutations), of which 4,894 (86%) were deletions (1 exon or larger) and 784 (14%) were duplications (1 exon or larger). There were 1,445 small mutations (smaller than 1 exon, 20% of all mutations), of which 358 (25%) were small deletions and 132 (9%) small insertions and 199 (14%) affected the splice sites. Point mutations totalled 756 (52% of small mutations) with 726 (50%) nonsense mutations and 30 (2%) missense mutations. Finally, 22 (0.3%) mid-intronic mutations were observed. In addition, mutations were identified within the database that would potentially benefit from novel genetic therapies for DMD including stop codon read-through therapies (10% of total mutations) and exon skipping therapy (80% of deletions and 55% of total mutations)

    Analysis of shared heritability in common disorders of the brain

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    Paroxysmal Cerebral Disorder
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