SARS-CoV-2 viral load is linked to remdesivir efficacy in severe Covid-19 admitted to intensive care.

Remdesivir therapy has been declared as efficient in the early stages of Covid-19. Of the 339 patients (males 55.8%, age 71(59;77) years) with a detectable viral load, 140 were treated with remdesivir (of those 103 in the ICU and 57 immunosuppressed) and retrospectively compared with 199 patients (of those 82 in the ICU and 28 immunosuppressed) who were denied therapy due to advanced Covid-19. The viral load was estimated by detecting nucleocapsid antigen in serum (n = 155, median 217(28;1524)pg/ml), antigen in sputum (n = 18, COI 18(4.6;32)), nasopharyngeal antigen (n = 44, COI 17(8;35)) and the real-time PCR (n = 122, Ct 21(18;27)). After adjustment for confounders, patients on remdesivir had better 12-month survival (HR 0.66 (0.44;0.98), p = 0.039), particularly when admitted to the ICU (HR 0.49 (0.29;0.81), p = 0.006). For the immunocompromised patients, the difference did not reach statistical significance (HR 0.55 (0.18;1.69), p = 0.3). The other most significant confounders were age, ICU admission, mechanical ventilation, leukocyte/lymphocyte ratio, admission creatinine and immunosuppression. The impact of monoclonal antibodies or previous vaccinations was not significant. Despite frequent immune suppression including haemato-oncology diseases, lymphopenia, and higher inflammatory markers in the remdesivir group, the results support remdesivir administration with respect to widely available estimates of viral load in patients with high illness severity.

[Destruction of the Humeral Head in Sensory Deficit due to the Spinal Hemorhagia. Case Report]. / Destrukce hlavice humeru pri senzitivním deficitu po mísní hemoragii - kazuistika.

Degenerative changes of the shoulder are a common complication in patients after spinal cord injury. The main cause is chronic overload to the shoulder joint due to manual wheelchair propulsion and transfers. Reduced shoulder function has a significant impact on all aspects of daily life. Shoulder arthroplasty in this group of patients is a challenging procedure because of the unique demand on the shoulder. This report presents the case of a wheelchair user who additionally experienced a complete loss of sensation around her shoulder. As a result of a repetitive strain during transfers from the wheelchair to the ground, the humeral head was destroyed.

Flow cytometric method for estimation of 5-bromo-2´-deoxyuridine content in rat serum.

Labelling of DNA in replicating cells using 5-bromo-2´-deoxyuridine (BrdU) is widely used, however the rapid clearance and metabolisation of BrdU in the living organism is a critical issue. Although the pharmacokinetic of BrdU in experimental animals is empirically approximated, the exact time-curve remains unknown. Here we present novel method for estimation of the BrdU content in the blood serum. The application is based on the in vitro cocultivation of tumour cells with the examined serum and the subsequent quantification of the incorporated BrdU in the DNA using flow cytometry analysis. Our results demonstrate that this approach can quantify the BrdU concentration in serum at 1 micromol.dm(-3) and might represent an attractive alternative to conventional chromatographic analysis. The employment of tumour cells as "detectors" of the BrdU content in serum provides an advantage over high pressure liquid chromatography (HPLC), as this approach allows us to approximate not only the concentration of BrdU, but also to determine, whether BrdU is present in the blood serum in effective concentration to reliable label all cells undergoing the S-phase of the cell cycle. The presented application might be a helpful tool for studies on pharmacokinetics of BrdU or other thymidine analogues when testing various administration routes or protocols.

Lichen secondary metabolites are responsible for induction of apoptosis in HT-29 and A2780 human cancer cell lines.

Lichens are a known source of approximately 800 unique secondary metabolites, many of which play important ecological roles, including regulating the equilibrium between symbionts. However, only a few of these compounds have been assessed for their effectiveness against various in vitro cancer models. Moreover, the mechanisms of biological activity of lichen secondary metabolites on living cells (including cancer cells) are still almost entirely unknown. In the present study, we investigated the mechanisms of cytotoxicity of four lichen secondary metabolites (parietin, atranorin, usnic acid and gyrophoric acid) on A2780 and HT-29 cancer cell lines. We found that usnic acid and atranorin were more effective anti-cancer compounds when compared to parietin and gyrophoric acid. Usnic acid and atranorin were capable of inducing a massive loss in the mitochondrial membrane potential, along with caspase-3 activation (only in HT-29 cells) and phosphatidylserine externalization in both tested cell lines. Induction of both ROS and especially RNS may be responsible, at least in part, for the cytotoxic effects of the tested compounds. Based on the detection of protein expression (PARP, p53, Bcl-2/Bcl-xL, Bax, p38, pp38) we found that usnic acid and atranorin are activators of programmed cell death in A2780 and HT-29, probably through the mitochondrial pathway.

Variable responses of different human cancer cells to the lichen compounds parietin, atranorin, usnic acid and gyrophoric acid.

One of the ways for searching for potentially new anti-cancer drugs is the testing of various naturally synthesized compounds. Lichens are a source of unique chemical agents of which some have already been proved to be effective against various cancer in vitro models. Our study reports on the sensitivity of up to nine human cancer cell lines (A2780, HeLa, MCF-7, SK-BR-3, HT-29, HCT-116 p53(+/+), HCT-116 p53(-/-), HL-60 and Jurkat) to the anti-proliferative/cytotoxic effects of four typical secondary metabolites of lichens (parietin, atranorin, usnic acid and gyrophoric acid). Variations in the dynamics of tumour cell line populations were evaluated by the MTT, clonogenic and viability assays, cell proliferation and detachment, cell cycle transition and apoptotic nuclear morphology, thereby confirming their concentration- and time-dependent cytotoxicity. However, in comparison with parietin and gyrophoric acid, the suppression of viability and cell proliferation by usnic acid or atranorin was found to be more efficient at equitoxic doses and correlated more strongly with an increased number of floating cells or a higher apoptotic index. Moreover, the analysis of cell cycle distribution also revealed an accumulation of cells in S-phase. This study has confirmed a differential sensitivity of cancer cell lines to lichen secondary metabolites.

The influence of heavy metals on the production of extracellular polymer substances in the processes of heavy metal ions elimination.

Wastewaters from a chemical industry polluted by heavy metal ions represent a hazard for all living organisms. It can mean danger for ecosystems and human health. New methods are sought alternative to traditional chemical and physical processes. Active elimination process of heavy metals ions provided by living cells, their components and extracellular products represents a potential way of separating toxic heavy metals from industrial wastewaters. While the abilities of bacteria to remove metal ions in solution are extensively used, fungi have been recognized as a promising kind of low-cost adsorbents for removal of heavy-metal ions from aqueous waste sources. Yeasts and fungi differ from each other in their constitution and in their abilities to produce variety of extracellular polymeric substances (EPS) with different mechanisms of metal interactions. The accumulation of Cd(2+), Cr(6+), Pb(2+), Ni(2+) and Zn(2+) by yeasts and their EPS was screened at twelve different yeast species in microcultivation system Bioscreen C and in the shaking Erlenmayer's flasks. This results were compared with the production of yeast EPS and the composition of yeast cell walls. The EPS production was measured during the yeast growth and cell wall composition was studied during the cultivations in the shaking flasks. At the end of the process extracellular polymers and their chemical composition were isolated and amount of bound heavy metals was characterized. The variable composition and the amount of the EPS were found at various yeast strains. It was influenced by various compositions of growth medium and also by various concentrations of heavy metals. It is evident, that the amount of bound heavy metals was different. The work reviews the possibilities of usage of various yeast EPS and components of cell walls in the elimination processes of heavy metal ions. Further the structure and properties of yeasts cell wall and EPS were discussed. The finding of mechanisms mentioned above is necessary to identify the functional groups entered in the metals elimination processes.

[DNA image cytometry in urothelial carcinomas. A pilot study of a new application module of the Lucia G DNA analysis system]. / Obrazová DNA cytometrie uroteliálních karcinomu. Pilotní studie v novém aplikacním modulu DNA analýzy systému LUCIA G.

OBJECTIVE: To introduce and test a standardized measurement protocol for DNA image cytometry into a newly developed LUCIA G system application program. Contribution to a discussion concerning the possibility of using the histology sections for DNA image cytometry. STUDY DESIGN: Routine biopsy material from 18 urinary bladder cancer cases was analyzed (Grade 1: n = 6, Grade 2: n = 6, Grade 3: n = 6), both in histological and in cytoseparated preparations. More than one hundred diagnostic and more than 30 reference cells were measured. DNA features (mean DNA value, 2cDI, Böcking's grade of malignancy) and histogram types in Auer's classification (AI-IV) were compared. RESULTS: Most carcinomas measured were aneuploid (two thirds G1, all G2, G3). The most common histogram type was A IV. Malignancy grade was mostly slightly higher in cytoseparated material, the shape of the histogram was analogous. Two carcinomas looking euploid in histology sections were proven aneuploid in cytoseparation. CONCLUSION: More convenient tissue section measurement provided useful DNA profile information in most cases. Those without proven aneuploidy should be additionally measured in cytoseparations. An experienced pathologist meeting strictly measurement protocol demands is an important part of the measurement system.

Image analysis of transparent particle systems by mathematical morphology methods.

The particle images are often distorted by apparent holes due to undeflected transmitted light. These apparent holes must be disregarded for a consequent image analysis. The reconstruction of the real particles by methods of mathematical morphology was used. The problems associated with touching particles were also dealt with. The method is illustrated on an ion-exchanger system.

The diagnosis of dioxin-associated illness.

The clinical recognition of dioxin-associated illness can be extremely difficult for the physician. After analyzing the relative sensitivity and specificity of reported manifestations of exposure to 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD), we suggest criteria for the diagnosis of dioxin toxicity. Exposure to higher doses of 2,3,7,8-TCDD may lead to the appearance of chloracne and the increased excretion of porphyrins and porphyria cutanea tarda. Liver function abnormalities, peripheral neuropathy, hyperlipidemia, and evidence of weakness and depression may occur following exposure; however, these findings are less specific since diseases such as diabetes or alcoholism could cause several of these problems. The long-term effects of exposure to low-dose TCDD are currently uncertain.

Is 2,3,7,8-TCDD (dioxin) a carcinogen for humans?

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has suddenly become the focal point of controversy over the relationship of chemical waste to human health. Specific concern exists regarding its potential association with human malignancy. Subcellular, cellular, and whole-animal experiments suggest that TCDD exerts much of its activity by inducing enzymes that protect the intact organism from the assault of environmental contamination. TCDD is a potent inducer of aryl hydrocarbon hydroxylase, although wide variations between species do exist. Conventional tests for mutagenicity have produced conflicting results. Animal experiments have shown the development of tumors following chronic low level ingestion of TCDD. The human evidence regarding the potential carcinogenicity of TCDD comes from occupational, military and environmental exposures. Several studies have come out of Sweden suggesting an association between sarcoma and exposure to herbicides. Although there is little solid evidence that 2,3,7,8-TCDD produces substantial chronic disability or premature death in man, a significant body of experimental evidence for its carcinogenicity makes it likely that a small number of human malignancies may be due to its action. Since 2,3,7,8-TCDD is an unwanted contaminant it could be eliminated with little measurable consequence.