Subpopulation composition of peripheral blood lymphocytes in COVID-19

The pathogenesis of severe coronavirus infection COVID-19 is associated with activation of immune system, cytokine storm, impaired blood clotting, microvascular thrombosis, organ ischemia and multiple organ dysfunction syndrome. The role of various lymphocyte subpopulations in COVID-19 is still debated. The aim of our study was to analyze the subpopulational profile of peripheral blood lymphocytes in COVID-19 patients as compared with healthy donors.The study included 20 COVID-19 patients (11 males and 9 females,) and 26 healthy donors. Average age of the patients was 52 and 56 years, respectively. Clinical examinations were performed by standard laboratory methods. Peripheral blood lymphocytes were isolated in the Ficoll gradient. The cells were stained with antibodies to specific antigens of main lymphocyte populations, endothelial cells, and apoptotic cell markers. The analysis was performed by flow cytometry. The results showed that all patients had elevated C-reactive protein (14- to 35-fold), ferritin (1.2- to 13-fold), D-dimers (1.2- to 90-fold). 55% of men had a decrease in the absolute number of lymphocytes, in women this index was at the low normal limit. Cytometric analysis showed that, among peripheral blood lymphocytes, the proportion of functional cells expressing the CD45 marker ranged from 2 to 12% in 70% of patients, as compared with 80-99% among the donors. The proportion of CD45+ lymphocytes significantly correlated with the level of hemoglobin, but not with the levels of inflammatory biochemical markers. Among the functional lymphocytes of patients, there was a decrease in the proportion of CD3+, CD4+, CD8+T cells, increased proportion of natural killer CD56+ and the apoptotic (AnnexinV+) cell contents, but the proportion of CD19 and HLA-DR+B cells was not changed. Analysis of the lymphocyte (LC) subpopulations that did not express CD45 marker showed that this fraction contained different lymphocyte subsets with reduced expression of CD4, CD8, CD19, CD56 etc. in the blood of patients and donors. Higher percentage of endothelial cells expressing CD62P marker made the difference between patients and donors.Laboratory determination of lymphocyte subsets in blood samples of COVID-19 patients does not reflect the real severity pattern of the disease, thus requiring studies of the CD45-expressing functional cell populations

A Systematic Study of Gene Mutations in Urothelial Carcinoma; Inactivating Mutations in TSC2 and PIK3R1

Abstract BACKGROUND: Urothelial carcinoma (UC) is characterized by frequent gene mutations of which activating mutations in FGFR3 are the most frequent. Several downstream targets of FGFR3 are also mutated in UC, e.g., PIK3CA, AKT1, and RAS. Most mutation studies of UCs have been focused on single or a few genes at the time or been performed on small sample series. This has limited the possibility to investigate co-occurrence of mutations. METHODOLOGY/PRINCIPAL FINDINGS: We performed mutation analyses of 16 genes, FGFR3, PIK3CA, PIK3R1 PTEN, AKT1, KRAS, HRAS, NRAS, BRAF, ARAF, RAF1, TSC1, TSC2, APC, CTNNB1, and TP53, in 145 cases of UC. We show that FGFR3 and PIK3CA mutations are positively associated. In addition, we identified PIK3R1 as a target for mutations. We demonstrate a negative association at borderline significance between FGFR3 and RAS mutations, and show that these mutations are not strictly mutually exclusive. We show that mutations in BRAF, ARAF, RAF1 rarely occurs in UC. Our data emphasize the possible importance of APC signaling as 6% of the investigated tumors either showed inactivating APC or activating CTNNB1 mutations. TSC1, as well as TSC2, that constitute the mTOR regulatory tuberous sclerosis complex were found to be mutated at a combined frequency of 15%. CONCLUSIONS/SIGNIFICANCE: Our data demonstrate a significant association between FGFR3 and PIK3CA mutations in UC. Moreover, the identification of mutations in PIK3R1 further emphasizes the importance of the PI3-kinase pathway in UC. The presence of TSC2 mutations, in addition to TSC1 mutations, underlines the involvement of mTOR signaling in UC

The role of complement in the susceptibility to invasive aspergillosis

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Synthesis of New Sulfur-Containing Derivatives of Furanoallocolchicinoids

Reaction of hydroxyl-containing heterocyclic colchicinoids with S-nucleophiles led to the formation of furanoallocolchicinoid sulfides in a high yield