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Simultaneous determination of lopinavir, saquinavir and ritonavirin in human plasma using liquid chromatography – ion trap mass spectrometry

100%
Lipiński M., Bielawski K. P., Słomińska E. M., Smoleński R. T.
European Journal of Translational and Clinical Medicine
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2021
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vol. 4
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issue 2
60-67
EN
Background: Lopinavir, saquinavir, and ritonavir are viral protease inhibitors (PIs) developed for and widely used in the therapy of human immunodeficiency virus (HIV)-related disease. These compounds are also active in vitro against the pathogens causing tuberculosis, malaria and coronavirus infections. PIs have been regarded as a platform for the design of inhibitors targeting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-encoded proteases. This study aimed to develop a liquid chromatography/mass spectrometry (LC/MS) procedure for accurate simultaneous determination of concentrations of these three PIs in the plasma. Methods: Samples of human plasma were protein precipitated with 0.3 M zinc sulfate in a water/methanol solution (30:70, v/v). The extracts were analyzed with reversed-phase chromatography coupled with the electrospray ionization (ESI) source of the ion trap mass detector operating in mEass spectrometry (MS) and tandem mass spectrometry (MS/MS) modes. Results: Calibration curves demonstrated good linearity from 0.01 to 10 µg/mL and acceptable reproducibilities and recoveries. Conclusions: The described procedure proves that a very basic ion-trap LC/MS system could be applied for selective, rapid, and precise determination of antiviral protease inhibitors.
2
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Photodynamic effect of lanthanide derivatives of meso-tetra(N-methyl-4-pyridyl)porphine against Staphylococcus aureus

88%
Jurczak A., Szramka B., Grinholc M., Legendziewicz J., Bielawski K. P.
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2008
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vol. 55
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issue 3
581-585
EN
Photodynamic therapy (PDT), used for cancer treatment, is also an alternative method for eradication of drug-resistant bacteria. This method utilizes a nontoxic light-activated dye, called a photosensitizer, and visible light to produce reactive oxygen species that lead to bacterial cell death. The purpose of this study was to investigate the bactericidal effect of PDT using lanthanide derivatives of meso-tetra(N-methyl-4-pyridyl)porphine against Staphylococcus aureus strains. The new photosensitizers appeared to be photodynamically ineffective. No enhancement of antistaphylococcal activity of TMPyP was observed after the conjugation of the porphyrin with lanthanide ions. Additionally, a significant difference in the susceptibility of two bacterial strains to unmodified TMPyP was observed.
3
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Photodynamic effect of protoporphyrin diarginate (PPArg2) on methicillin-resistant Staphylococcus aureus and human dermal fibroblasts

88%
Grinholc M., Kawiak A., Kurlenda J., Graczyk A., Bielawski K. P.
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2008
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vol. 55
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issue 1
85-90
EN
The worldwide rise in the antibiotic resistance of bacteria forces the development of alternative antimicrobial treatments. A potential approach is photodynamic inactivation (PDI). The aim of the present study was to determine the phototoxicity of protoporphyrin diarginate (PPArg2) against methicillin-resistant Staphylococcus aureus and human dermal fibroblasts. Different concentrations (0 to 20 µM) of PPArg2 and light dose of 6 J cm-2 were tested. Cell viability was evaluated using the methylthiazoletetrazolium (MTT) assay. Incubation with 10 µM followed by illumination yielded a 3.6 log10-unit reduction in the viable count for Staphylococcus aureus. At the same experimental conditions, only 22.5% of the fibroblasts were photoinactivated. Protoporphyrin diarginate at concentrations up to 20 µM demonstrated no toxicity towards S. aureus or fibroblasts when not irradiated. These results suggest that the protoporphyrin diarginate exerts a high bactericidal effect against methicillin-resistant S. aureus strain without harming eukaryotic cells.
4
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The profile of ErbB/Her family genes copy number assessed by real-time PCR in parathyroid adenoma and hyperplasia associated with sporadic primary hyperparathyroidism

88%
Bednarz N., Błaut K., Sworczak K., Osęka T., Bielawski K. P.
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issue 1
83-88
EN
Hyperparathyroidism (pHPT) is a relatively frequent endocrinopathy, however, the molecular mechanisms of its etiology remain poorly understood. This disorder is mainly associated with benign tumours (adenoma) and hyperplasia of the parathyroid, hence, the focus is directed also to genes that are likely to be involved in carcinogenesis. Among such genes are ErbB/Her family genes already used in diagnosis of other tumours (e.g., breast carcinoma) and reported also to play a role in development of endocrine lesions. So far, ErbB-1/Her-1/EGFR expression has been detected in pHPT-associated adenomas and hyperplasia as opposed to no expression in normal parathyroid tissue. Moreover, losses or gains of the fragments of chromosomes where ErbB/Her genes are located have been reported. In this study, the gene dosage of ErbB/Her family genes were determined for the first time in parathyroid adenomas, hyperplasia and morphologically unchanged tissue in order to establish their putative role in the development of the disease. Genomic DNA was isolated from 33 patients with sporadic hyperparathyroidism and the gene copy numbers were assessed using real-time PCR. The ErbB/Her genes' profile was unaltered in most of the examined samples. Two low-level amplifications of ErbB-1/Her-1/EGFR gene, two deletions of ErbB-2/Her-2, and six deletions of ErbB-4/Her-4 were found. The ErbB-3/Her-3 gene remained unaffected. No correlation with clinical parameters was found for any gene. Both the low number of alterations and a lack of their associations with clinical parameters exclude the prognostic value of the ErbB/Her genes family in parathyroid tumourigenesis. Nevertheless, the ErbB-4/Her-4 deletions seem to be interesting for further investigations, especially in the context of PTH secretion.
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