Publications by authors named "Krzysztof Urbanowicz"

Article Synopsis
  • 5-Fluorouracil (5-FU) is a primary treatment for colorectal cancer and is often combined with leucovorin (LV) to enhance its effectiveness by targeting thymidylate synthase (TS).
  • The study compared Arfolitixorin (Arfo), an active form of folate, to LV in combination with 5-FU in patients with colorectal cancer liver metastases to see which produces better TS inhibition and folate levels.
  • Results showed that Arfo led to significantly higher levels of folate (MeTHF) and increased TS inhibition compared to LV, indicating that Arfo may be a more effective option, though the difference in TS inhibition wasn't statistically significant.
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Research indicates a role for EBI2 receptor in remyelination, demonstrating that its deficiency or antagonism inhibits this process. However, activation of EBI2 with its endogenous ligand, oxysterol 7α,25-dihydroxycholesterol (7α,25OHC), does not enhance remyelination beyond the levels observed in spontaneously remyelinating tissue. We hypothesized that the short half-life of the natural ligand might explain this lack of beneficial effects and tested a synthetic analogue, CF-7α,25OHC, in the cuprizone model.

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Article Synopsis
  • - Lesch-Nyhan Disease (LND) is a rare genetic disorder caused by mutations in a specific gene, resulting in neurological issues like abnormal movement and self-harm, which are hard to treat.
  • - A systematic review of 34 studies found that many had high bias, and there were significant differences in how treatments were applied and evaluated, leading to inconsistent results.
  • - The most researched treatments, such as S-Adenosylmethionine and Deep Brain Stimulation, need more investigation, and there is a pressing need for better study designs to improve the assessment of treatment effectiveness in LND.
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Objectives: Experimental models to test the effective protection against cardiac ischemia injury are still challenging in pre-clinical studies. The use of myocardial slices creates a special link between testing isolated cardiomyocytes and whole-heart research. In this work, we investigated the effects of oxygen deprivation in a hypoxic chamber and treatment with cobalt chloride (CoCl) on the nucleotide profile in isolated mouse myocardial slices.

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Molnupiravir, an orally administered prodrug of β-d-N4-hydroxycytidine (NHC), is incorporated into newly synthesized RNA by viral RNA-dependent RNA polymerase (RdRp). It is used for treatment of SARS-CoV-2 infections. Incorporation of NHC triphosphate into viral RNA inhibits replication of the virus, at least in part by introducing deleterious mutations.

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Background: In vivo solid-phase microextraction (SPME) is a minimally invasive, non-exhaustive sample-preparation technique that facilitates the direct isolation of low molecular weight compounds from biological matrices in living systems. This technique is especially useful for the analysis of phytocannabinoids (PCs) in plant material, both for forensic purposes and for monitoring the PC content in growing Cannabis spp. plants.

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Thymidylate synthase (TS) is an enzyme responsible for the conversion of deoxyuridine monophosphate (dUMP) to deoxythymidine monophosphate (dTMP), with the co-substrate 5,10-methylenetetrahydrofolate (5,10-CH-THF) as the methyl donor. TS is the only enzyme capable of de novo biosynthesis of dTMP in humans, a nucleotide crucial for DNA synthesis and therefore cell proliferation and survival. As such, TS is a major drug target in chemotherapy by compounds such as 5-fluorouracil.

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Article Synopsis
  • * Results showed an increased ADA1 to ADA2 ratio in MS patients, with significant increases in plasma ADA1 and a decrease in CSF ADA2, while also revealing that endothelial cells have higher ADA1 activity compared to astrocytes and pericytes.
  • * The research concludes that pro-inflammatory cytokines affect the activities of ADA1 and ADA2 differently in various brain cell types, reflecting the changes seen in MS patients' CSF, potentially influencing the neuroinflammatory
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The success of nonlinear noise reduction applied to a single channel recording of human voice is measured in terms of the recognition rate of a commercial speech recognition program in comparison to the optimal linear filter. The overall performance of the nonlinear method is shown to be superior. We hence demonstrate that an algorithm that has its roots in the theory of nonlinear deterministic dynamics possesses a large potential in a realistic application.

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We present a method of noise-level estimation that is valid even for high noise levels. The method makes use of the functional dependence of coarse-grained correlation entropy K2(epsilon ) on the threshold parameter epsilon. We show that the function K2(epsilon ) depends, in a characteristic way, on the noise standard deviation sigma.

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