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Background: Nephronophthisis (NPH) comprises a heterogeneous group of inherited renal ciliopathies clinically characterized by progressive kidney failure. So far, definite diagnosis is based on molecular testing only. Here, we studied the feasibility of NPHP1 and NPHP4 immunostaining of nasal epithelial cells to secure and accelerate the diagnosis of NPH. Methods: Samples of 86 individuals with genetically determined renal ciliopathies were analyzed for NPHP1 localization using immunofluorescence microscopy (IF). A sub-cohort of 35 individuals was also analyzed for NPHP4 localization. Western blotting was performed to confirm IF results. Results: NPHP1 and NPHP4 were both absent in all individuals with disease-causing NPHP1 variants including one with a homozygous missense variant (c.1027G > A; p.Gly343Arg) formerly classified as a "variant of unknown significance." In individuals with an NPHP4 genotype, we observed a complete absence of NPHP4 while NPHP1 was severely reduced. IF results were confirmed by immunoblotting. Variants in other genes related to renal ciliopathies did not show any impact on NPHP1/NPHP4 expression. Aberrant immunostaining in two genetically unsolved individuals gave rise for a further genetic workup resulting in a genetic diagnosis for both with disease-causing variants in NPHP1 and NPHP4, respectively. Conclusions: IF of patient-derived respiratory epithelial cells may help to secure and accelerate the diagnosis of nephronophthisis—both by verifying inconclusive genetic results and by stratifying genetic diagnostic approaches. Furthermore, we provide in vivo evidence for the interaction of NPHP1 and NPHP4 in a functional module. [ABSTRACT FROM AUTHOR]

This article, published in the journal Neuropediatrics, discusses the use of therapeutic apheresis (TA) in pediatric patients with acute neurological disorders. The study, conducted at the Hannover Medical School, analyzed data on the clinical course of 31 patients who received TA between 2016 and 2023. The patients had various diagnoses, including autoimmune encephalitis, transverse myelitis, ADEM, Guillain-Barré syndrome, myasthenia gravis, and others. The study found that both plasmapheresis and immunoadsorption were effective and safe in improving the patients' conditions. However, further controlled studies are needed to determine the potential superiority of either method. [Extracted from the article]

G protein-coupled receptors (GPCRs) activate G proteins and undergo a complex regulation by interaction with GPCR kinases (GRKs) and the formation of receptor–arrestin complexes. However, the impact of individual GRKs on arrestin binding is not clear. We report the creation of eleven combinatorial HEK293 knockout cell clones lacking GRK2/3/5/6, including single, double, triple and the quadruple GRK knockout. Analysis of β-arrestin1/2 interactions for twelve GPCRs in our GRK knockout cells enables the differentiation of two main receptor subsets: GRK2/3-regulated and GRK2/3/5/6-regulated receptors. Furthermore, we identify GPCRs that interact with β-arrestins via the overexpression of specific GRKs even in the absence of agonists. Finally, using GRK knockout cells, PKC inhibitors and β-arrestin mutants, we present evidence for differential receptor–β-arrestin1/2 complex configurations mediated by selective engagement of kinases. We anticipate our GRK knockout platform to facilitate the elucidation of previously unappreciated details of GRK-specific GPCR regulation and β-arrestin complex formation. GPCR kinases (GRKs) regulate GPCR interactions and thus functions. Here, the authors report a comprehensive panel of GRK knockout cells, used to assess the GRK-specific β-arrestin recruitment. Selective engagement of GRKs induces distinct GPCR–β-arrestin complexes. [ABSTRACT FROM AUTHOR]

Copyright of Der Internist is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Der Urologe A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Kanzelmeyer NK, Ahlenstiel T, Drube J, Froede K, Kreuzer M, Broecker V, Ehrich JHH, Melk A, Pape L. Protocol biopsy-driven interventions after pediatric renal transplantation. Pediatr Transplantation 2010: 14:1012-1018 © 2010 John Wiley & Sons A/S. The therapeutic value of protocol biopsies (PBs) in renal transplant recipients remains unclear. We performed protocol biopsies in 57 children six months after transplantation. We increased the CNI dose in patients with borderline findings. In cases of Banff grade Ia, six prednisolone IV-pulses were given and the CNI dose was increased. CNI toxicity and polyomavirus nephropathy led to a reduction in the CNI dose. GFR was compared with a control group of 51 children with no PBs transplanted in the same period. Forty-two percent of PBs had no pathological changes, 24% IF/TA. Borderline findings were detected in 11%, Banff grade Ia in 15% (CNI), toxicity in 8%, and one case showed polyomavirus nephropathy. GFR after 1.5 and 2.5 yr was similar in both groups. GFR 3.5 yr after transplantation was significantly higher in the intervention group (57 ± 17 vs. 46 ± 20). Patients treated with low-dose CNI and everolimus had a significantly lower number of pathological findings in PBs. The performance of protocol biopsies followed by a standardized treatment algorithm led to better graft function 3.5 yr after transplantation. Prospective randomized studies to confirm our findings are needed. [ABSTRACT FROM AUTHOR]