Several COVID-19 convalescents suffer from the post-acute COVID-syndrome (PACS)/long COVID, with symptoms that include fatigue, dyspnea, pulmonary fibrosis, cognitive dysfunctions or even stroke. Given the scale of the worldwide infections, the long-term recovery and the integrative health-care in the nearest future, it is critical to understand the cellular and molecular mechanisms as well as possible predictors of the longitudinal post-COVID-19 responses in convalescent individuals. The immune system and T cell alterations are proposed as drivers of post-acute COVID syndrome. However, despite the number of studies on COVID-19, many of them addressed only the severe convalescents or the short-term responses. Here, we performed longitudinal studies of mild, moderate and severe COVID-19-convalescent patients, at two time points (3 and 6 months from the infection), to assess the dynamics of T cells immune landscape, integrated with patients-reported symptoms. We show that alterations among T cell subsets exhibit different, severity- and time-dependent dynamics, that in severe convalescents result in a polarization towards an exhausted/senescent state of CD4+ and CD8+ T cells and perturbances in CD4+ Tregs. In particular, CD8+ T cells exhibit a high proportion of CD57+ terminal effector cells, together with significant decrease of naïve cell population, augmented granzyme B and IFN-γ production and unresolved inflammation 6 months after infection. Mild convalescents showed increased naïve, and decreased central memory and effector memory CD4+ Treg subsets. Patients from all severity groups can be predisposed to the long COVID symptoms, and fatigue and cognitive dysfunctions are not necessarily related to exhausted/senescent state and T cell dysfunctions, as well as unresolved inflammation that was found only in severe convalescents. In conclusion, the post-COVID-19 functional remodeling of T cells could be seen as a two-step process, leading to distinct convalescent immune states at 6 months after infection. Our data imply that attenuation of the functional polarization together with blocking granzyme B and IFN-γ in CD8+ cells might influence post-COVID alterations in severe convalescents. However, either the search for long COVID predictors or any treatment to prevent PACS and further complications is mandatory in all patients with SARS-CoV-2 infection, and not only in those suffering from severe COVID-19.

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The aim of the present study is to reconstruct sedimentary conditions of Middle Jurassic rocks that contain siderites to identify the mineral composition of the inserbeds and to recognize the origin of the siderite. Thin inserbeds of siderite rocks occur most frequently within Bajocian siliciclastic deposits and, more rarely, Aalenian and Bathonian. The research material comes from 11 boreholes located in the north and northeastern margins of the Holy Cross Mountains. The research methods included sedimentological analyses, and studies in polarizing and scanning electron microscopes, staining of carbonates, cathodoluminescence, X-ray structural analysis, and stable carbon and oxygen isotopic determinations were used. Middle Jurassic sideritic rocks are most often represented by clayey siderites, which also include muddy and sandy varieties and siderite sandstones. There are also local occurrences of coquinas, claystones, mudstones, and siderite conglomerates. The main component of sideritic rocks is sideroplesite. Berthierine, pistomesite, calcite, and ankerite are important components, too. The action of diagenetic processes of cementation, compaction, replacement, and alteration within the Middle Jurassic deposits was most intense during the eo- and mesodiagenesis. The sedimentological analysis showed that most of the studied siderites were formed in a low-oxygenated marine environment, mainly in the transition zone between the normal and storm wave bases and in the lower and middle shoreface zones. The results of the petrographic, mineralogical, and geochemical studies indicated the origin of the sideritic rocks mainly in the marine environment, with the participation of meteoric water. There were slight differences in the chemical composition of sideroplesite depending on the environment it crystallized in. There was no correlation between the values of the carbon isotope determinations in the sideroplesite and the environmental conditions of its crystallization. Slight differences were visible in the case of the average values of δ18O in the sideroplesite.

Walka ze zjawiskiem antybiotykooporności drobnoustrojów stanowi wyzwanie dla współczesnej medycyny. Szczepy wielolekooporne (ang. multidrug resistant – MDR) są przyczyną przewlekłych, trudnych w terapii zakażeń związanych z opieką medyczną. Narastająca skala problemu wymusza poszukiwanie nowych rozwiązań, które pomogłyby ograniczyć rozprzestrzenianie niebezpiecznych patogenów. Dotychczasowe badania, wykorzystujące nanocząstki metali, przynoszą obiecujące wyniki. W tej grupie na szczególną uwagę zasługują nanocząstki miedzi, które wykazują działanie przeciwdrobnoustrojowe w stosunku do wielu bakterii, wirusów czy grzybów. Obecnie jako środek przeciwdrobnoustrojowy wykorzystuje się miedź. Liczne placówki medyczne zastąpiły dotychczasowe wyposażenie albo jego elementy przedmiotami wykonanymi z miedzi lub pokrytymi miedzianą powłoką (klamki, ramy łóżek, przełączniki światła). Takie działanie umożliwia redukcję liczby patogenów w środowiskach związanych z opieką medyczną, tym samym ograniczając szerzenie się infekcji. Istotnym aspektem jest również potencjalna cytotoksyczność miedzi oraz jej nanocząstek. Dotychczas uzyskane dane pokazują, że nanocząstki metali wykazują 7–50 razy mniejszą toksyczność niż formy jonowe. Wiedza na temat bezpiecznego stosowania nanocząstek w medycynie jest wciąż niewystarczająca, dlatego należy podejmować kolejne badania w tym zakresie.