Current management of locally advanced rectal cancer achieves high cure rates, distant metastatic spread being the main cause of patients' death. Total neoadjuvant therapy (TNT) employs (chemo)radiotherapy and combined chemotherapy prior to surgery to improve the treatment outcomes. TNT has been shown to reduce significantly distant metastases, increase disease-free survival by 5 - 10% in 3 years, and finally also overall survival (≈ 5% in 7 years). It proved to double the rate of pathologic complete responses, making it an attractive strategy for non-operative management to avoid permanent colostomy in patients with distal tumors. In addition, it endorses adherence to the therapy due to better tolerance and, potentially, shortens its overall duration. A number of questions related to TNT remain currently unresolved including the indications, preferred radiotherapy and chemotherapy regimens, their sequence, timing of surgery, and role of adjuvant therapy. A stratified approach may be the optimal way to go.
- MeSH
- chemoradioterapie MeSH
- kombinovaná terapie MeSH
- lidé MeSH
- motivace MeSH
- nádory rekta * terapie patologie MeSH
- neoadjuvantní terapie * MeSH
- protokoly protinádorové kombinované chemoterapie terapeutické užití MeSH
- staging nádorů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- MeSH
- filatelie * MeSH
- houby * MeSH
- lidé MeSH
- peniciliny MeSH
- významné osobnosti MeSH
- Check Tag
- lidé MeSH
- O autorovi
- Fleming, Alexander, 1881-1955 Autorita
- MeSH
- dějiny 20. století MeSH
- lidé MeSH
- objevování léků dějiny MeSH
- peniciliny * dějiny MeSH
- Check Tag
- dějiny 20. století MeSH
- lidé MeSH
Setting of maximum limits for a number of plant alkaloids is under discussion in the EU. The novel method developed and optimized in this study enables simultaneous determination of 21 tropane alkaloids (TAs) and 33 pyrrolizidine (PAs) together with their N-oxides (PANOs). For analysis of aqueous-methanolic extract, reversed phase ultra-high-performance liquid chromatography and tandem mass spectrometry (RP-U-HPLC-MS/MS) was employed. The method was validated for frequently contaminated matrices (i) sorghum, (ii) oregano, and (iii) mixed herbal tea. The recoveries at two spiking levels were in the range of 82-115%, 80-106%, and 78-117%, respectively, and repeatabilities were less than 19% for all analyte/matrix combinations. As regards the achieved limits of quantification (LOQ), their values were in the range of 0.5-10 μg kg-1. The crucial problem encountered during method development, co-elution of multiple groups of isomeric alkaloids, was overcome by subsequent sample separation in the second chromatographic system, hydrophilic interaction liquid chromatography (HILIC), providing different separation selectivity. Lycopsamine, echinatine, and indicine (co-elution group 1) and N-oxides of indicine and intermedine (co-elution group 2), which could not be resolved on the commonly used RP column, were possible to separate fully by using the HILIC system.
- MeSH
- alkaloidy analýza MeSH
- isomerie MeSH
- kontaminace potravin analýza MeSH
- limita detekce MeSH
- pyrrolizidinové alkaloidy analýza MeSH
- reprodukovatelnost výsledků MeSH
- rostliny chemie MeSH
- tandemová hmotnostní spektrometrie metody MeSH
- tropany analýza MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Publikační typ
- časopisecké články MeSH
Silymarin, milk thistle (Silybum marianum) extract, contains a mixture of mostly isomeric bioactive flavonoids and flavonolignans that are extensively studied, especially for their possible liver-protective and anticancer effects. Because of the differing bioactivities of individual isomeric compounds, characterization of their proportion in a mixture is highly important for predicting its effect on health. However, because of silymarin's complexity, this is hardly feasible by common analytical techniques. In this work, ultraperformance liquid chromatography coupled with drift tube ion mobility spectrometry and quadrupole time-of-flight mass spectrometry was used. Eleven target silymarin compounds (taxifolin, isosilychristin, silychristins A and B, silydianin, silybins A and B, 2,3-cis-silybin B, isosilybins A and B and 2,3-dehydrosilybin) and five unknown flavonolignan isomers detected in the milk thistle extract were fully separated in a 14.5-min analysis run. All the compounds were characterized on the basis of their accurate mass, retention time, drift time, collision cross section and fragmentation spectra. The quantitative approach based on evaluation of the ion mobility data demonstrated lower detection limits, an extended linear range and total separation of interferences from the compounds of interest compared with the traditional approach based on evaluation of liquid chromatography-quadrupole time-of-flight mass spectrometry data. The following analysis of a batch of milk thistle-based food supplements revealed significant variability in the silymarin pattern, especially in the content of silychristin A and silybins A and B. This newly developed method might have high application potential, especially for the characterization of materials intended for bioactivity studies in which information on the exact silymarin composition plays a crucial role. Graphical Abstract.
- MeSH
- flavonolignany analýza izolace a purifikace MeSH
- hmotnostní spektrometrie metody MeSH
- iontová mobilní spektrometrie metody MeSH
- isomerie MeSH
- ostropestřec mariánský chemie MeSH
- silymarin analýza izolace a purifikace MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Publikační typ
- časopisecké články MeSH
Pro všední den, ISSN 2464-6245 90.
Vydání 1. 23 stran : barevné ilustrace, faksimile ; 21 cm
Publikace z Mikrobiologického ústavu AV ČR, v. v. i., přináší přehled dosud vydaných známek s tematikou mikroskpických hub.; Přehled dosud vydaných poštovních známek s tematikou mikroskopických hub.
- Konspekt
- Poštovní služby a správa
- NLK Obory
- humanitní vědy a umění
- NLK Publikační typ
- brožury
Herbal-based dietary supplements have become increasingly popular. The extract from milk thistle (Silybum marianum), is often used for the treatment of liver diseases. However, serious concerns exist regarding the efficacy, composition, as well as the safety of these over-the-counter preparations. Therefore, the aim of the present study was to investigate the composition as well as chemical and biological safety of 26 milk thistle-based dietary supplements purchased from both the U.S. and Czech markets between 2016 and 2017. The study was focused on a determination of the composition of active ingredients, as well as analyses of possible contaminants including: mycotoxins, plant alkaloids, and pesticide residues, as well as the microbial purity. High-throughput analyses were performed using advanced U-HPLC-HRMS techniques. Large differences in the silymarin content were observed among individual milk thistle preparations, often in contrast with the information provided by the manufacturers. In addition, substantial inter-batch differences in silymarin content were also demonstrated. In all milk thistle preparations tested, large numbers and high concentrations of mycotoxins and several pesticides, as well as the substantial presence of microbiological contamination were detected, pointing to serious safety issues. In conclusion, our results strongly indicate the need for strict controls of the composition, chemical contaminants, as well as the microbiological purity of commercial milk thistle extracts used for the treatment of liver diseases. Poor definition of these preparations together with contamination by biologically active substances may not only account for the inconsistency of clinical observations, but also be responsible for possible herbal-based dietary supplements-induced liver injury.
- MeSH
- antioxidancia chemie fyziologie MeSH
- biologické přípravky chemie farmakologie MeSH
- fytoterapie metody MeSH
- lidé MeSH
- mykotoxiny chemie MeSH
- nemoci jater farmakoterapie MeSH
- ostropestřec mariánský chemie mikrobiologie MeSH
- pesticidy chemie MeSH
- potravní doplňky mikrobiologie MeSH
- rostlinné extrakty chemie farmakologie MeSH
- silymarin chemie farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Movile Cave, a unique groundwater ecosystem in southern Romania, was discovered in 1986. This chemoautotrophic cave contains an abundant and diverse fauna with terrestrial and aquatic invertebrate communities, including 33 endemic species. Since its discovery, studies have focused mainly on cave chemoautotrophic bacteria, while the microfungal community has been largely neglected. In this study, we determined the microfungal species living on various substrates in Movile Cave and compared this spectrum with the mycobiota detected outside the cave (outside air-borne and soil-borne microfungi). To investigate all of the niches, we collected samples for two consecutive years from the dry part of the cave (cave air and sediment, corroded limestone walls, isopod feces, and isopod and spider cadavers) and from the post-siphon part of the cave, i.e., Airbell II (sediment and floating microbial mat). A total of 123 microfungal species were identified from among several hundred isolates. Of these, 96 species were only detected in the cave environment and not outside of the cave, while 90 species were from the dry part of the cave and 28 were from Airbell II. The most diverse genera were Penicillium (at least 18 species) and Aspergillus (14 species), followed by Cladosporium (9 species). Surprisingly, high CFU counts of air-borne microfungi were found inside the cave; they were even higher than outside the cave during the first year of investigation.
