38 research outputs found

    Helicobacter pylori cytotoxin-associated gene A virulence and its association with the epithelial-mesenchymal transition in gastric cancer

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    Gastric cancer is currently one of the most prevalent malignancies worldwide with a high mortality rate. Helicobacter pylori (H. pylori) infection significantly contributes to the onset and progression of gastric cancer mainly due to the induction of chronic inflammatory responses. The pathogenicity of H. pylori is associated with a vast number of virulence factors among which cytotoxin-associated gene A (CagA) plays a crucial role. We conducted a literature review of PubMed, Web of Science, and Scopus on September 1st, 2021. There were no limits regarding the year and the language of publication. Articles included in this review concerned human and animal studies. The following search string was applied during the search: (gastric cancer) AND (epithelial-mesenchymal transition) AND (Helicobacter pylori) AND (cytotoxin-associated gene A). The final analysis included 135 articles independently reviewed by the authors. H. pylori CagA-positive strains seem to be more virulent compared to the CagA-negative strains. CagA pathogenicity includes the increased secretion of pro-inflammatory cytokines, induction of cancer stem cell-like properties, apoptosis prevention, or overactivation of particular oncogenic pathways. H. pylori might induce epithelial-mesenchymal transition (EMT) via numerous pathways, among which CagA-related pathogenicity is considered to be of high significance. Mechanisms associated with CagA action are involved in the maintenance of chronic H. pylori infection, subsequent EMT induction, and further onset and progression of gastric cancer. Because of a huge number of H. pylori strains with different virulence mechanisms, the clinical outcome of patients is also associated with the particular type of strain that infected a patient

    LC-QTOF-MS Analysis and Activity Profiles of Popular Antioxidant Dietary Supplements in Terms of Quality Control

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    The dietary supplements with claimed antioxidant activity constitute a substantial part of the dietary supplement market. In this study, we performed the LC-QTOF-MS analysis and investigated the activity profiles of popular antioxidant dietary supplements from different chemical groups in terms of quality control. The commonly used antioxidant tests and statistical analysis revealed that substantial part of the results was comparable if 1 g sample was considered, but while comparing single and daily doses, significant differences in antioxidant values were noticed in all assays. The best antioxidant activity was obtained in ORAC assay (from 142 to 13814 μM of Trolox equivalents per 1 g of sample), and the strongest correlation occurred between TPC and ORAC. The LC-QTOF-MS analysis revealed that catechins were present in samples having the best antioxidant activity and that dietary supplements showing the weakest activity contained very small amount of any chemical constituents

    Insights into the Transposable Mobilome of Paracoccus spp. (Alphaproteobacteria)

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    Several trap plasmids (enabling positive selection of transposition events) were used to identify a pool of functional transposable elements (TEs) residing in bacteria of the genus Paracoccus (Alphaproteobacteria). Complex analysis of 25 strains representing 20 species of this genus led to the capture and characterization of (i) 37 insertion sequences (ISs) representing 9 IS families (IS3, IS5, IS6, IS21, IS66, IS256, IS1182, IS1380 and IS1634), (ii) a composite transposon Tn6097 generated by two copies of the ISPfe2 (IS1634 family) containing two predicted genetic modules, involved in the arginine deiminase pathway and daunorubicin/doxorubicin resistance, (iii) 3 non-composite transposons of the Tn3 family, including Tn5393 carrying streptomycin resistance and (iv) a transposable genomic island TnPpa1 (45 kb). Some of the elements (e.g. Tn5393, Tn6097 and ISs of the IS903 group of the IS5 family) were shown to contain strong promoters able to drive transcription of genes placed downstream of the target site of transposition. Through the application of trap plasmid pCM132TC, containing a promoterless tetracycline resistance reporter gene, we identified five ways in which transposition can supply promoters to transcriptionally silent genes. Besides highlighting the diversity and specific features of several TEs, the analyses performed in this study have provided novel and interesting information on (i) the dynamics of the process of transposition (e.g. the unusually high frequency of transposition of TnPpa1) and (ii) structural changes in DNA mediated by transposition (e.g. the generation of large deletions in the recipient molecule upon transposition of ISPve1 of the IS21 family). We also demonstrated the great potential of TEs and transposition in the generation of diverse phenotypes as well as in the natural amplification and dissemination of genetic information (of adaptative value) by horizontal gene transfer, which is considered the driving force of bacterial evolution

    Clove Essential Oil and Its Main Constituent, Eugenol, as Potential Natural Antifungals against Candida spp. Alone or in Combination with Other Antimycotics Due to Synergistic Interactions

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    The occurrence of candidiasis, including superficial infections, has recently increased dramatically, especially in immunocompromised patients. Their treatment is often ineffective due to the resistance of yeasts to antimycotics. Therefore, there is a need to search for new antifungals. The aim of this study was to determine the antifungal effect of clove essential oil (CEO) and eugenol (EUG) towards both reference and clinical Candida spp. strains isolated from the oral cavity of patients with hematological malignancies, and to investigate their mode of action and the interactions in combination with the selected antimycotics. These studies were performed using the broth microdilution method, tests with sorbitol and ergosterol, and a checkerboard technique, respectively. The CEO and EUG showed activity against all Candida strains with a minimal inhibitory concentration (MIC) in the range of 0.25–2 mg/mL. It was also found that both natural products bind to ergosterol in the yeast cell membrane. Moreover, the interactions between CEO and EUG with several antimycotics—cetylpyridinium chloride, chlorhexidine, silver nitrate and triclosan—showed synergistic or additive effects in combination, except nystatin. This study confirms that the studied compounds appear to be a very promising group of phytopharmaceuticals used topically in the treatment of superficial candidiasis. However, this requires further studies in vivo

    Chemical composition and in vitro activity of Origanum vulgare L., Satureja hortensis L., Thymus serpyllum L. and Thymus vulgaris L. essential oils towards oral isolates of Candida albicans and Candida glabrata

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    The purpose of this research was to investigate the chemical composition of essential oils (EOs) from: Origanum vulgare L., Satureja hortensis L., Thymus serpyllum L. and Thymus vulgaris L. (Lamiaceae) cultivated in Poland, and to study their antifungal activity towards clinical isolates of oral Candida spp. The hydrodistilled essential oils were analyzed using the GC-MS method. The antifungal activity was evaluated in vitro against oral isolates and reference strains of Candida albicans and C. glabrata, using the broth microdilution method according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) and Clinical and Laboratory Standards Institute (CLSI) guidelines, allowing for estimation of minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC). GC-MS analysis revealed that carvacrol was the main EO compound in oregano and summer savory, while thymol and linalool were the major ingredients of thyme and wild thyme oils, respectively. The EOs possessed fungicidal activity against C. albicans and C. glabrata, including oral isolates, with MIC = 125 – 2000 mg/L, MFC = 250 – 4000 mg/L and MFC/MIC = 1 – 4, depending on the yeast and plant species. The most active was thyme oil – with MIC = 125 – 500 mg/L, MFC = 250 – 500 mg/L and MFC/MIC = 1 – 2

    Chemical composition and microbiological evaluation of essential oil from Hyssopus officinalis L. with white and pink flowers

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    Hyssopus officinalis L. is a common plant that is most usually found in three color forms - f. cyaneus (blue), f. ruber Mill. (purple/pink) and f. albus Alef (white). In the present work, we evaluated the chemical composition and antimicrobial activity of essential oils obtained from Polish-sourced white- and pink-flowered H. officinalis. Gas chromatography-mass spectrometry analysis of the essential oil has shown that both forms of color have a different content of main components. The principle essential oil component of white-flowered H. officinalis L. was pinocamphone (51%), while pink-flowered H. officinalis L. contained almost equal amounts of pinocamphone (28.8%) and isopinocamphone (21.9%). Of note, the essential oil of the pink form was more active against Grampositive bacteria, especially against Bacillus subtilis

    Estimation of Potential Availability of Essential Oil in Some Brands of Herbal Teas and Herbal Dietary Supplements.

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    The aim of the study was to estimate potential availability of essential oil in some brands of herbal products.A comparison was performed on the basis of the essential oil yield in the unprocessed raw materials such as leaves of peppermint and lemon balm and inflorescence of chamomile as well as herbal tea bags and in dietary supplements. The yield of essential oil was determined by distillation. Essential oil was analyzed by GC-FID and GC-MS.It was found that the average potential availability of essential oils in the products such as dietary supplements for the doses recommended by the producers is lower than in the corresponding tea infusions: for peppermint formulations approximately 6-fold lower, for the formulations with lemon balm about 4-fold lower, and for the chamomile preparations about 3-fold lower. It was found that essential oils extracted from herbal teas have a similar chemical profile with characteristic deviations in the amount of individual components, which arise from the origin of the raw material.In contrast to homogenous pharmaceutical herbal mixtures consistent with, the Pharmacopoeia requirements, herbal teas (available in grocery stores) and dietary supplements are often out of control in terms of the yield and composition of the essential oil, which is primarily responsible for the health benefits and aromatic qualities of these products. Analysis of the composition of the dietary supplements showed that they contain on average significantly lower amounts of plant material compared to the herbal teas

    The In Vitro Activity of Essential Oils against Helicobacter Pylori Growth and Urease Activity

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    The anti-H. pylori properties of 26 different commercial essential oils were examined in vitro by MIC (minimal inhibitory concentration) determination for the reference strain H. pylori ATCC 43504. We selected 9 essential oils with different anti-Helicobacter activities and established their phytochemical composition and urease inhibition activities. Phytochemical analysis of the selected essential oils by GC-MS method and antioxidant activity were performed. The phenol red method was used to screen the effect of essential oils on urease activity expressed as IC50 (the half of maximal inhibitory concentration). The most active essential oils, with MIC = 15.6 mg/L, were thyme, lemongrass, cedarwood and lemon balm oils; MIC = 31.3 mg/L—oregano oil; MIC = 62.5 mg/L—tea tree oil; MIC = 125 mg/L—pine needle, lemon and silver fir oils with bactericidal effect. Urease activity was inhibited by these oils with IC50 ranged from 5.3 to > 1049.9 mg/L. The most active was cedarwood oil (IC50 = 5.3 mg/L), inhibiting urease at sub-MIC concentrations (MIC = 15.6 mg/L). The statistical principal component analysis allowed for the division of the oils into three phytochemical groups differing in their anti-H. pylori activity. To summarize, the activity in vitro of the five essential oils silver fir, pine needle, tea tree, lemongrass, and cedarwood oils against H. pylori was found in this paper for the first time. The most active against clinical strains of H. pylori were cedar wood and oregano oils. Moreover, cedarwood oil inhibited the urease activity at subinhibitory concentrations. This essential oil can be regarded as a useful component of the plant preparations supporting the eradication H. pylori therapy

    The main components of essential oils obtained from unprocessed materials and lemon balm teas.

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    <p><sup>#</sup>Designation according to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0130714#pone.0130714.t001" target="_blank">Table 1</a>.</p><p>IR- retention indices (from temperature-programming, using definition of Van den Dool and Kratz [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0130714#pone.0130714.ref010" target="_blank">10</a>].</p><p>tr.—less than 0.1%.</p><p>The main components of essential oils obtained from unprocessed materials and lemon balm teas.</p
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