264 research outputs found

    'New ordinary' of 'winners' : South Africa as part of BRICS

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    ASC – Publicaties niet-programma gebonde

    Reversed polarized delivery of an aquaporin-2 mutant causes dominant nephrogenic diabetes insipidus

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    Vasopressin regulates body water conservation by redistributing aquaporin-2 (AQP2) water channels from intracellular vesicles to the apical surface of renal collecting ducts, resulting in water reabsorption from urine. Mutations in AQP2 cause autosomal nephrogenic diabetes insipidus (NDI), a disease characterized by the inability to concentrate urine. Here, we report a frame-shift mutation in AQP2 causing dominant NDI. This AQP2 mutant is a functional water channel when expressed in Xenopus oocytes. However, expressed in polarized renal cells, it is misrouted to the basolateral instead of apical plasma membrane. Additionally, this mutant forms heterotetramers with wild-type AQP2 and redirects this complex to the basolateral surface. The frame shift induces a change in the COOH terminus of AQP2, creating both a leucine- and a tyrosine-based motif, which cause the reversed sorting of AQP2. Our data reveal a novel cellular phenotype in dominant NDI and show that dominance of basolateral sorting motifs in a mutant subunit can be the molecular basis for disease

    Износ кругов из СТМ при зубошлифовании

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    The problems of increasing the efficiency of grinding highly precision gearwheels of the 3–4 degree of precision using superhard material tools are discussed. The efficiency of cubic boron nitride dish grinding wheels in various bonds has been studied. Recommendations how to use cubic boron nitride wheels in gear grinding are given

    De Novo Mutations in PDE10A Cause Childhood-Onset Chorea with Bilateral Striatal Lesions.

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    Chorea is a hyperkinetic movement disorder resulting from dysfunction of striatal medium spiny neurons (MSNs), which form the main output projections from the basal ganglia. Here, we used whole-exome sequencing to unravel the underlying genetic cause in three unrelated individuals with a very similar and unique clinical presentation of childhood-onset chorea and characteristic brain MRI showing symmetrical bilateral striatal lesions. All individuals were identified to carry a de novo heterozygous mutation in PDE10A (c.898T>C [p.Phe300Leu] in two individuals and c.1000T>C [p.Phe334Leu] in one individual), encoding a phosphodiesterase highly and selectively present in MSNs. PDE10A contributes to the regulation of the intracellular levels of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). Both substitutions affect highly conserved amino acids located in the regulatory GAF-B domain, which, by binding to cAMP, stimulates the activity of the PDE10A catalytic domain. In silico modeling showed that the altered residues are located deep in the binding pocket, where they are likely to alter cAMP binding properties. In vitro functional studies showed that neither substitution affects the basal PDE10A activity, but they severely disrupt the stimulatory effect mediated by cAMP binding to the GAF-B domain. The identification of PDE10A mutations as a cause of chorea further motivates the study of cAMP signaling in MSNs and highlights the crucial role of striatal cAMP signaling in the regulation of basal ganglia circuitry. Pharmacological modulation of this pathway could offer promising etiologically targeted treatments for chorea and other hyperkinetic movement disorders

    Identification of Risk Factors for Dupilumab-associated OculaSurface Disease in Patients with Atopic Dermatitis

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    This study identified risk factors for the development of dupilumab-associated ocular surface disease in patients with moderate-to-severe atopic dermatitis in a large prospective daily practice cohort. Data from the Dutch BioDay Registry were used to assess the risk of developing dupilumab-associated ocular surface di-sease, by performing univariate and multivariate logistic regression analyses. A total of 469 patients were included, of which 152/469 (32.4%) developed dupi-lumab-associated ocular surface disease. Multivariate analysis showed a statistically significant association of the development of dupilumab-associated ocular surface disease with a history of any eye disease (his-tory of self-reported episodic acute allergic conjunctivitis excluded) combined with the use of ophthalmic medication at the start of dupilumab (odds ratio 5.16, 95% confidence interval 2.30–11.56, p < 0.001). In conclusion, a history of any eye disease (history of self-reported episodic acute allergic conjunctivitis ex-cluded) combined with the use of ophthalmic medication at baseline was associated with the development of dupilumab-associated ocular surface disease in patients with atopic dermatitis

    Dupilumab Drug Survival and Associated Predictors in Patients With Moderate to Severe Atopic Dermatitis Long-term Results From the Daily Practice BioDay Registry

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    IMPORTANCE Long-term data on dupilumab drug survival in patients with atopic dermatitis (AD) are scarce. Furthermore, little is known about the factors associated with drug survival of dupilumab in AD.OBJECTIVE To describe the drug survival of dupilumab in patients with AD and to identify associated predictors.DESIGN, SETTING, AND PARTICIPANTS This cohort studywas based on data from the multicenter prospective daily practice BioDay registry, in which 4 university and 10 nonuniversity hospitals in the Netherlands participated. Analysis included patients (age &gt;= 18 years) participating in the BioDay registry with a follow-up of at least 4 weeks. The first patient treated with dupilumab was recorded in the BioDay registry in October 2017; data lock took place in December 2020, and data analysis was performed from October 2017 to December 2020.MAIN OUTCOMES AND MEASURES Drug survivalwas analyzed by Kaplan-Meier survival curves and associated characteristics by using univariate and multivariate Cox regression analysis.RESULTS A total of 715 adult patients with AD (mean [SD] age, 41.8 [16.0] years; 418 [58.5%] were male) were included with a 1-year, 2-year, and 3-year overall dupilumab drug survival of 90.3%, 85.9%, and 78.6%, respectively. Characteristics associated with shorter drug survival owing to ineffectiveness were the use of immunosuppressant drugs at baseline (hazard ratio [HR], 2.64; 95% CI, 1.10-6.37) and being a nonresponder at 4 weeks (HR, 8.68; 95% CI, 2.97-25.35). Characteristics associated with shorter drug survival owing to adverse effects were the use of immunosuppressant drugs at baseline (HR, 2.69; 95% CI, 1.32-5.48), age 65 years or older (HR, 2.94; 95% CI, 1.10-7.87), and Investigator Global Assessment score of very severe AD (HR, 3.51; 95% CI, 1.20-10.28).CONCLUSIONS AND RELEVANCE This cohort study demonstrated a good overall 1-year, 2-year, and 3-year dupilumab drug survival. Patients using immunosuppressive therapy at baseline and those with an absence of treatment effect at week 4 tended to discontinue treatment owing to ineffectiveness more frequently. Using immunosuppressant drugs at baseline, older age, and Investigator Global Assessment score of very severe AD were characteristics associated with an increased risk for discontinuation owing to adverse effects. These data provide more insight and new perspectives regarding dupilumab treatment in AD and can contribute to the optimization of patient outcomes.</p

    Monoubiquitination of syntaxin 3 leads to retrieval from the basolateral plasma membrane and facilitates cargo recruitment to exosomes

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    Syntaxin 3 (Stx3), a SNARE protein located and functioning at the apical plasma membrane of epithelial cells, is required for epithelial polarity. A fraction of Stx3 is localized to late endosomes/lysosomes, although how it traffics there and its function in these organelles is unknown. Here we report that Stx3 undergoes monoubiquitination in a conserved polybasic domain. Stx3 present at the basolateral—but not the apical—plasma membrane is rapidly endocytosed, targeted to endosomes, internalized into intraluminal vesicles (ILVs), and excreted in exosomes. A nonubiquitinatable mutant of Stx3 (Stx3-5R) fails to enter this pathway and leads to the inability of the apical exosomal cargo protein GPRC5B to enter the ILV/exosomal pathway. This suggests that ubiquitination of Stx3 leads to removal from the basolateral membrane to achieve apical polarity, that Stx3 plays a role in the recruitment of cargo to exosomes, and that the Stx3-5R mutant acts as a dominant-negative inhibitor. Human cytomegalovirus (HCMV) acquires its membrane in an intracellular compartment and we show that Stx3-5R strongly reduces the number of excreted infectious viral particles. Altogether these results suggest that Stx3 functions in the transport of specific proteins to apical exosomes and that HCMV exploits this pathway for virion excretion
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