Congenital deficiency reveals critical role of ISG15 in skin homeostasis

Ulcerating skin lesions are manifestations of human ISG15 deficiency, a type I interferonopathy. However, chronic inflammation may not be their exclusive cause. We describe two siblings with recurrent skin ulcers that healed with scar formation upon corticosteroid treatment. Both had a homozygous nonsense mutation in the ISG15 gene, leading to unstable ISG15 protein lacking the functional domain. We characterized ISG15(-/-) dermal fibroblasts, HaCaT keratinocytes, and human induced pluripotent stem cell-derived vascular endothelial cells. ISG15-deficient cells exhibited the expected hyperinflammatory phenotype, but also dysregulated expression of molecules critical for connective tissue and epidermis integrity, including reduced collagens and adhesion molecules, but increased matrix metalloproteinases. ISG15(-/-) fibroblasts exhibited elevated ROS levels and reduced ROS scavenger expression. As opposed to hyperinflammation, defective collagen and integrin synthesis was not rescued by conjugation-deficient ISG15. Cell migration was retarded in ISG15(-/-) fibroblasts and HaCaT keratinocytes, but normalized under ruxolitinib treatment. Desmosome density was reduced in an ISG15(-/-) 3D epidermis model. Additionally, there were loose architecture and reduced collagen and desmoglein expression, which could be reversed by treatment with ruxolitinib/doxycycline/TGF-beta 1. These results reveal critical roles of ISG15 in maintaining cell migration and epidermis and connective tissue homeostasis, whereby the latter likely requires its conjugation to yet unidentified targets

Analog-sensitive cell line identifies cellular substrates of CDK9.

Transcriptional cyclin-dependent kinases regulate all phases of transcription. Cyclin-dependent kinase 9 (CDK9) has been implicated in the regulation of promoter-proximal pausing of RNA polymerase II and more recently in transcription termination. Study of the substrates of CDK9 has mostly been limited to in vitro approaches that lack a quantitative assessment of CDK9 activity. Here we analyzed the cellular phosphoproteome upon inhibition of CDK9 by combining analog-sensitive kinase technology with quantitative phosphoproteomics in Raji B-cells. Our analysis revealed the activity of CDK9 on 1102 phosphosites quantitatively, and we identified 120 potential cellular substrates. Furthermore, a substantial number of CDK9 substrates were described as splicing factors, highlighting the role of CDK9 in transcription-coupled splicing events. Based on comparison to in vitro data, our findings suggest that cellular context fundamentally impacts the activity of CDK9 and specific selection of its substrates

(59.5-x) P2O5-30Na(2)O-10Al(2)O(3)-0.5CoO-xNd(2)O(3)glassy system: an experimental investigation on structural and gamma-ray shielding properties

In this study, five different glasses encoded ND1, ND2, ND3, ND4 and ND5 based on (59.5-x) P2O5-30Na(2)O-10Al(2)O(3)-0.5CoO-xNd(2)O(3)(x = 1, 2, 3, 4 and 5 mol%) glass system were fabricated. Using two gamma- ray energies emitted from point sources, 356 keV (Ba-133) and 662 keV (Cs-137), gamma-ray attenuation coefficients were measured as a function of the Nd(2)O(3)concentration. The theoretical values of the mass attenuation coefficient were calculated using the XCOM program at 0.015-15-MeV photon energies. As it is underlined in the results section, the mass attenuation coefficient increases as the Nd(2)O(3)concentration increases. X-ray diffraction (XRD) was characterized for fabricated glasses. Moreover, different shielding parameters such as half-value layer (HVL), mean free path (MFP), effective atomic numbers (Z(eff)), basic gamma-ray attenuation properties such as exposure buildup factors (EBF) and energy absorption buildup factors (EABF) at different penetration depths were calculated. With increasing Nd(2)O(3)additive in glass samples, half-value layer (HVL), average free path (MFP), exposure and energy absorption buildup factor (EBF and EABF) values decrease. On the other hand,Z(eff)values increase with increasing Nd(2)O(3)additive in glass samples at the photon energy 0.015-15 MeV. The results highlighted that ND5 sample with highest value of Nd2O3(5 mol%) showed excellent nuclear radiation shielding properties

Amyloid arthropathy associated with multiple myeloma: polyarthritis without synovial infiltration of CD20+ or CD38+ cells.

To describe histological, immunohistochemical and ultrastructural features of synovial biopsies of amyloid arthropathy associated with multiple myeloma (MM)