Publications by authors named "Petr Vitek"

The structure, function, and molecular mechanisms of lichen survival in harsh habitats like Antarctica and Alpine localities, where environmental extremes change frequently, are highly interesting yet largely underexplored. We used high resolution microscopy, Raman spectroscopy, and chlorophyll a fluorescence to investigate the basic structure and function, i.e.

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Microorganisms inhabiting gypsum have been observed in environments that differ greatly in water availability. Gypsum colonized by microorganisms, including cyanobacteria, eukaryotic algae, and diverse heterotrophic communities, occurs in hot, arid or even hyperarid environments, in cold environments of the Antarctic and Arctic zones, and in saline and hypersaline lakes and ponds where gypsum precipitates. Fossilized microbial remnants preserved in gypsum were also reported.

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Background: Anorectal hemangioma is a rare and frequently misdiagnosed cause of lower gastrointestinal (GI) bleeding. Here, we present a minimally invasive therapy with selective embolization.

Case Summary: A 21-year-old male patient experienced painless rectal bleeding since childhood and was treated for ulcerative colitis.

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Background And Aims: Lumen-apposing metal stents (LAMSs) have proven to be effective for drainage of pancreatic walled-off necrosis (WON), although associated adverse events (AEs) have been reported. Anchoring coaxial double-pigtail plastic stents (DPSs) within LAMSs have been proposed to prevent LAMS-related AEs but have not been assessed in prospective studies. We aimed to evaluate the utility of such measures with a randomized controlled trial.

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Background: Heterotopic pancreas is defined as pancreatic tissue located outside the pancreatic parenchyma that lacks an anatomic or vascular connection to the normal pancreas. Symptomatic gastric heterotopic pancreas is a rare condition that can manifest as acute or chronic pancreatitis. Asymptomatic heterotopic pancreas does not require treatment, while symptomatic lesions should be resected.

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The interaction of ultrahigh-performance concrete (UHPC) and normal-strength concrete (NSC) is one of the main issues for strengthening conventional concrete structures or other applications where NSC and UHPC are interrelated. UHPC stands out for its strength and durability, while NSC is significantly inexpensive and easier to work with. Efficiently designed structures can exploit the advantages of both mixtures.

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Objective: Spiritual Care is a well established part of palliative medicine. Are religiosity / spirituality also ressources of patients during the early phases of a head neck cancer (HNC) disease?

Material And Methods: We included 113 HNC patients (27 women, 84 men, 2 divers) to a prospective study using questionnaires focused on actual burden (NRS), spirituality as ressource (SpREUK-15, spiritual needs (SpNQ-20), interpretation of illness (IIQ), and life satisfaction of patients (BMLSS-10, BMLSS-Support, WHO-5). 39 patients were still under therapy, 74 participants were cancer-survivors.

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Background And Aims: Colonoscopy with polypectomy are associated with a reduction in the incidence of colorectal cancer (CRC), as well as mortality, secondary to CRC. Because of the variation in physicians' performance and the risk of interval CRC after a colonoscopy, several quality indicators have been established. ADR (adenoma detection rate) is a generally accepted quality indicator.

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Objective: COVID-19 pandemic has impact on the oncology service system for tumor patients. What is the view of head and neck cancer patients (HNC) on this situation and which coping strategies were developed?

Material & Methods: In study 1 PRIO asked 433 tumor patients regarding their impressions/fears during the lockdown between April 15 and May 15, 2020 (online, standardized questionnaire). In 2 study 292 tumor patients reported their pandemic-induced perceived changes and coping strategies by established questionnaires (WHO-5, MLQ, GrAw-7).

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Article Synopsis
  • Two selected plant species are tested for their ability to stabilize contaminated soils, showing resistance to pollutants and retaining high contaminant levels at the roots.
  • Nanoscale zero-valent iron (nZVI) is evaluated for its impact on seed germination and seedling growth in contaminated soils, showing no harmful effects and even promoting shoot growth and root development.
  • Higher concentrations of nZVI increased the uptake of nutrients like Mg and Fe while decreasing the iron translocation factor, indicating its low toxicity and potential benefits for plant growth in contaminated soils.
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Background: Currently, the diagnosis and treatment of neuroblastomas-the most frequent solid tumors in children-exploit the norepinephrine transporter (hNET) via radiolabeled norepinephrine analogs. We aim to develop a nanomedicine-based strategy towards precision therapy by targeting hNET cell-surface protein with hNET-derived homing peptides.

Results: The peptides (seq.

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Lichens survive harsh weather of Antarctica as well as of other hostile environments worldwide. Therefore, this investigation is important to understand the evolution of life on Earth in relation to their stress tolerance strategy. We have used chlorophyll a fluorescence (ChlF) and Raman spectroscopy, respectively, to monitor the activation/deactivation of photosynthesis and carotenoids in three diverse Antarctic lichens, Dermatocarpon polyphyllizum (DP), Umbilicaria antarctica (UA), and Leptogium puberulum (LP).

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The current epidemic of antibiotic-resistant infections urges to develop alternatives to less-effective antibiotics. To assess anti-bacterial potential, a novel coordinate compound (RU-S4) was synthesized using ruthenium-Schiff base-benzimidazole ligand, where ruthenium chloride was used as the central atom. RU-S4 was characterized by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), and Raman spectroscopy.

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Raman imaging allows one to obtain spatially resolved chemical information in a nondestructive manner. Herein, we present analytical aspects of effective in situ and in vivo Raman imaging of algae and cyanobacteria from within their native rock habitats. Specifically, gypsum and halite inhabited by endolithic communities from the hyperarid Atacama Desert were analyzed.

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The use of photosystem II (PSII) inhibitors allows simulating cascade of defense and damage responses, including the oxidative stress. In our study, PSII inhibiting herbicide metribuzin was applied to the leaf of the model plant species . The temporally and spatially resolved cascade of defense responses was studied noninvasively at the leaf level by combining three imaging approaches: Raman spectroscopy as a principal method, corroborated by chlorophyll fluorescence (ChlF) and infrared thermal imaging.

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Lichens are successful colonizers in extreme environments worldwide, and they are considered to have played an important role during the evolution of life. Here, we have used a correlative approach, combining three optical signals (chlorophyll a fluorescence (ChlF), reflectance, and Raman spectra), to monitor hydration induced changes in photosynthetic properties of an Antarctic chlorolichen Dermatocarpon polyphyllizum. We measured these three signals from this lichen at different stages (after 4 h, 24 h, and 48 h) of hydration, and compared the data obtained from this lichen in "dry state" as well as in different "hydrated state".

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The biochemical responses of rock-inhabiting cyanobacteria towards native environmental stresses were observed in vivo in one of the Earth's most challenging extreme climatic environments. The cryptoendolithic cyanobacterial colonization, dominated by Chroococcidiopsis sp., was studied in an ignimbrite at a high altitude volcanic area in the Atacama Desert, Chile.

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Background: Data are limited on the effectiveness of anti-TNF and other biologics on psoriatric arthritis (PsA) in Central and Eastern Europe (CEE). The objective of this analysis was to evaluate the efficacy of etanercept (ETN) in PsA patients from CEE.

Methods: In PRESTA, patients were randomized to receive ETN 50 mg BIW or 50 mg QW for 12 weeks (double-blind phase) and ETN 50 mg QW for 12 additional weeks (open label).

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Nanobiosynthesis belongs to the most recent methods for synthesis of nanoparticles. This type of synthesis provides many advantages including the uniformity in particle shape and size. The biosynthesis has also a significant advantage regarding chemical properties of the obtained particles.

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The effects of herbicides from three mode-of-action groups - inhibitors of protoporphyrinogen oxidase (carfentrazone-ethyl), inhibitors of carotenoid biosynthesis (mesotrione, clomazone, and diflufenican), and inhibitors of acetolactate synthase (amidosulfuron) - were studied in sunflower plants (Helianthus annuus). Raman spectroscopy, chlorophyll fluorescence (ChlF) imaging, and UV screening of ChlF were combined to evaluate changes in pigment composition, photosystem II (PSII) photochemistry, and non-photochemical quenching in plant leaves 6d after herbicide application. The Raman signals of phenolic compounds, carotenoids, and chlorophyll were evaluated and differences in their intensity ratios were observed.

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Objectives: Piecemeal endoscopic mucosal resection (EMR) is frequently used for the treatment of non-poly-poid colorectal lesions larger than 20 mm. Nevertheless, local residual neoplasia occurs (LRN) in as much as 15 % of cases. The aim of our prospective interventional study was to evaluate the efficacy of treatment of LRN under standardized conditions.

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There are one-step and two-steps programs for colorectal cancer screening. The aim of all screening examinations is to detect early stage of the disease in asymptomatic patient. The aim of this article is actual review of current screening modalities such as fecal occult blood test, flexible sigmoideoscopy, colonoscopy, CT colonography, capsule endoscopy, blood-based tests and stool DNA tests.

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The Raman imaging method was successfully applied for mapping the distribution of biomolecules (e.g., pigments) associated with cryptoendolithic and hypoendolithic microorganisms, as well as the inorganic host mineral matrix that forms the habitat for the biota.

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