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A case of a patient with an early and severe visual impairment is described. Due to the occurrence of skin papules a suspect of pseudoxanthoma elasticum (PXE) was posed. PXE is a rare autosomal recessive disease clinically characterized by skin, cardiovascular and ocular manifestations, these last being those that most severely affect patients’ quality of life. A whole exome sequencing approach focusing on 340 genes related to the calcification process and/or to inherited retinal diseases (IRDs) was performed. Rare monoallelic sequence variants in ABCA4, ABCC6, IMPG1, POC1B and RAX2 were found. The presence of calcified elastic fibers was assessed by ultrastructural analysis on a skin biopsy. Diagnosis of PXE was based on clinical, biomolecular and morphological results, although the additional involvement of several IRD genes is important to explain the unexpectedly severe ophthalmological phenotype of the patient also in prognostic and therapeutic perspectives. Data indicate that genetic screening using a wide-spectrum analysis approach is essential to assist ophthalmologists in improving patient counseling.

Background: Pseudoxanthoma elasticum (PXE), due to rare sequence variants in the ABCC6 gene, is characterized by calcification of elastic fibers in several tissues/organs, however, the pathomechanisms have not been completely clarified. Although it is a systemic disorder on a genetic basis, it is not known why not all elastic fibers are calcified in the same patient and even in the same tissue. At present, data on soft connective tissue mineralization derive from studies performed on vascular tissues and/or on clinically affected skin, but there is no information on patients’ clinically unaffected skin. Methods: Skin biopsies from clinically unaffected and affected areas of the same PXE patient (n = 6) and from healthy subjects were investigated by electron microscopy. Immunohistochemistry was performed to evaluate p-SMAD 1/5/8 and p-SMAD 2/3 expression and localization. Results: In clinically unaffected skin, fragmented elastic fibers were prevalent, whereas calcified fibers were only rarely observed at the ultrastructural level. p-SMAD1/5/8 and p-SMAD2/3 were activated in both affected and unaffected skin. Conclusion: These findings further support the concept that fragmentation/degradation is necessary but not sufficient to cause calcification of elastic fibers and that additional local factors (e.g., matrix composition, mechanical forces and mesenchymal cells) contribute to create the pro-osteogenic environment.

In patients infected by SARS‐CoV‐2 who experience an exaggerated inflammation leading to pneumonia, monocytes likely play a major role but have received poor attention. Thus, we analyzed peripheral blood monocytes from patients with COVID‐19 pneumonia and found that these cells show signs of altered bioenergetics and mitochondrial dysfunction, had a reduced basal and maximal respiration, reduced spare respiratory capacity, and decreased proton leak. Basal extracellular acidification rate was also diminished, suggesting reduced capability to perform aerobic glycolysis. Although COVID‐19 monocytes had a reduced ability to perform oxidative burst, they were still capable of producing TNF and IFN‐γ in vitro. A significantly high amount of monocytes had depolarized mitochondria and abnormal mitochondrial ultrastructure. A redistribution of monocyte subsets, with a significant expansion of intermediate/pro‐inflammatory cells, and high amounts of immature monocytes were found, along with a concomitant compression of classical monocytes, and an increased expression of inhibitory checkpoints like PD‐1/PD‐L1. High plasma levels of several inflammatory cytokines and chemokines, including GM‐CSF, IL‐18, CCL2, CXCL10, and osteopontin, finally confirm the importance of monocytes in COVID‐19 immunopathogenesis., Investigation of patients with COVID‐19 pneumonia revealed that SARS‐CoV‐2 infection affects innate immunity by reshaping peripheral blood monocyte subsets and altering their functionality, in terms of bioenergetics, membrane potential and expression of checkpoint inhibitors.

Pseudoxanthoma elasticum (PXE) is a genetic disease considered as a paradigm of ectopic mineralization disorders, being characterized by multisystem clinical manifestations due to progressive calcification of skin, eyes, and the cardiovascular system, resembling an age-related phenotype. Although fibroblasts do not express the pathogenic ABCC6 gene, nevertheless these cells are still under investigation because they regulate connective tissue homeostasis, generating the "arena" where cells and extracellular matrix components can promote pathologic calcification and where activation of pro-osteogenic factors can be associated to pathways involving mitochondrial metabolism. The aim of the present study was to integrate structural and bioenergenetic features to deeply investigate mitochondria from control and from PXE fibroblasts cultured in standard conditions and to explore the role of mitochondria in the development of the PXE fibroblasts' pathologic phenotype. Proteomic, biochemical, and morphological data provide new evidence that in basal culture conditions (1) the protein profile of PXE mitochondria reveals a number of differentially expressed proteins, suggesting changes in redox balance, oxidative phosphorylation, and calcium homeostasis in addition to modified structure and organization, (2) measure of oxygen consumption indicates that the PXE mitochondria have a low ability to cope with a sudden increased need for ATP via oxidative phosphorylation, (3) mitochondrial membranes are highly polarized in PXE fibroblasts, and this condition contributes to increased reactive oxygen species levels, (4) ultrastructural alterations in PXE mitochondria are associated with functional changes, and (5) PXE fibroblasts exhibit a more abundant, branched, and interconnected mitochondrial network compared to control cells, indicating that fusion prevail over fission events. In summary, the present study demonstrates that mitochondria are modified in PXE fibroblasts. Since mitochondria are key players in the development of the aging process, fibroblasts cultured from aged individuals or aged in vitro are more prone to calcify, and in PXE, calcified tissues remind features of premature aging syndromes; it can be hypothesized that mitochondria represent a common link contributing to the development of ectopic calcification in aging and in diseases. Therefore, ameliorating mitochondrial functions and cell metabolism could open new strategies to positively regulate a number of signaling pathways associated to pathologic calcification.

The possible prognostic value of the position of the breakpoint within the M-BCR in patients with Phl+ CML is still being debated. We analyzed the DNA rearrangements and the transcript types of 244 patients and tried to correlate the data obtained with prognostic features, defined according to Sokal's risk index, and with chronic phase and/or survival duration. The exact location of the breakpoint, either 5' or 3' to the Hind III restriction site within the M-BCR was identified. Moreover, the exact M-BCR subregion was also identified. As a whole, 150 pts were rearranged in the 5' part and 94 in the 3' part of the M-BCR. No correlation was observed between the site of rearrangement on the one hand and the Sokal's prognostic index and survival, on the other. Transcript analysis was performed in 130 patients; 59 carried an a2b2 and 69 an a2b3 pattern. Two patients carried both transcripts. Of the patients rearranged in the 5' area, according to Southern blotting, 29.2% showed an a2b3 transcript. Therefore, R...