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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. METHODS: We randomly assigned consecutive patients with WON indications for drainage to EUS-guided transluminal drainage using LAMSs with (group A) or without (group B) DPSs. All LAMSs were to be removed after 3 weeks had elapsed from the index procedure with a preceding CT to decide whether additional steps needed to be taken (eg, transluminal necrosectomy or placing transluminal plastic stents in patients with incomplete resolution of WON). The main outcomes were failure of the index method, defined as necessity of reintervention (endoscopic, percutaneous, or surgical) before LAMS removal because of LAMS-related AEs and/or clinical deterioration; AE rates; and mortality with the LAMS in place. Variables were evaluated using the Mann-Whitney U test, χ2 test, or Fisher exact test as appropriate. P < .05 was considered significant. RESULTS: Sixty-seven patients (37.3% women; mean age, 54 ± 14.4 years) underwent LAMS placement with (n = 34) or without (n = 33) DPS placement in 2 tertiary centers. Baseline characteristics including demographics, etiology, comorbidity, and clinical presentation (sterile vs infected necrosis) were comparable between both groups. The technical success rate in placing LAMSs and DPSs was 100%. The global rate of AEs was significantly lower in group A versus group B (20.7% vs 51.5%, respectively; P = .008). Stent occlusion was the most frequently observed AE (14.7% vs 36.3%, P = .042). Failure of the index method was lower in group A versus group B (29.4% vs 48.5%, respectively; P = .109); however, the difference did not achieve statistical significance. The same applied to the mortality rate with LAMSs in place (2.9% vs 12.1%, P = .197). CONCLUSIONS: The addition of a coaxial DPS within a LAMS was associated with a significantly lower global rate of AEs and stent occlusion rate in EUS-guided drainage of WON. (Clinical trial registration number: NCT03923686.).
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Pancreatitis Aguda Necrotizante , Stents , Humanos , Femenino , Adulto , Persona de Mediana Edad , Anciano , Masculino , Estudios Prospectivos , Resultado del Tratamiento , Estudios Retrospectivos , Stents/efectos adversos , Pancreatitis Aguda Necrotizante/cirugía , Drenaje/métodos , Plásticos , Necrosis/etiología , EndosonografíaRESUMEN
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. The modality of final resection of heterotopic pancreas depends on its size and the depth of gastric wall involvement. METHODS AND RESULTS: A 36-year-old woman was admitted for recurrent epigastralgia. Abdominal computed tomography (CT) scan revealed that an abscess had formed in the gastric antrum. After multidisciplinary discussion we decided for conservative treatment with intravenous antibiotics and further detailed endoscopic diagnostic. Esophagogastroduodenoscopy revealed a submucosal mass with a central fistula and intermittent pus secretion in the prepyloric region of the gastric antrum, which was subsequently drained with a double pigtail stent under endoscopic ultrasound (EUS) and fluoroscopy. The possibility of pancreatic fluid collection in the case of heterotopic pancreas was suggested during the EUS examination, and histology subsequently confirmed heterotopic pancreatic tissue. The patient was in good condition and without any abdominal pain. According to a control CT scan after 10 weeks, the fluid collection was completely resolved. Due to the possible recurrence of pancreatitis, resection of heterotopic pancreas was proposed to the patient. Since the lesion involved the muscularis propria of the gastric wall, surgical resection of the mass was indicated. CONCLUSION: Fluid collections after acute pancreatitis in heterotopic pancreas in the gastric antrum can be successfully managed by endoscopy.
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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. At the interface of these materials in newly designed structures, the formwork can be modified at the interface to give the concrete surface sufficient roughness and thus cohesion as required. This improves both the tensile and shear strength of the contact resulting in the enhanced capacity of the composite structure. In this study, a button foil was inserted into the formwork for the UHPC and then a part of NSC was made. The shear strength of the interface without any stress component in the transverse direction was measured on small-scale samples. It was to justify the possibility of the use of this interface in real constructions such as beams and columns. The main objective of further research is to design a composite beam using a UHPC shell as formwork for NSC and protrusions at the interface. It is expected that the U-shaped shell made of the UHPC could significantly contribute to the load-bearing capacity of the resulting composite NSC−UHPC structure and also to its enhanced durability. In addition, if the NSC is enclosed in a shell of UHPC, it can be made from various secondary materials, therefore it can decrease cement consumption by more than 50%.
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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. RESULTS: Only 31/111 (28â%) patients feel themselve as spiritual and/or religious. 72â% are neither spiritual nor religious. 51/111 see reflexion about their cancer disease as a specific ressource to overcome their actual cancer situation. Spiritual needs are religious in 35/112, existential in 67/112, inner peace in 90/112, and generativity in 84/112 patients. The accepted own religiosity and the actual stadium of disease are highly relevant impact factors on spiritual needs and ressources. HNC patients show a high part of depressive moods (WHO-5) and are (in trend) un-satisfied with their life and support situation. CONCLUSION: Up to 90â% of HNC patients have specific spiritual needs which are often hidden. Modern concepts of integrative oncology discover them, and enourage via these ressources the quality of life and the coping of cancer patients.
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Neoplasias de Cabeza y Cuello , Neoplasias , Terapias Espirituales , Femenino , Neoplasias de Cabeza y Cuello/terapia , Humanos , Masculino , Estudios Prospectivos , Calidad de Vida , Espiritualidad , Encuestas y CuestionariosRESUMEN
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. But it is also a target of possible gaming and achieving an adequate number of colonoscopies only from screening may be a problem for some practices. The aim of this study was to compare ADR for colonoscopies done for various indications and to look for correlations between the ADR of screening and all examinations. METHODS: We retrospectively assessed the quality indicators of all colonoscopies performed in a nonuniversity hospital, Frydek-Mistek, from January 2013 to December 2017. We calculated the ADR for all colonoscopies in patients over 50 years of age (subdivided into screening, surveillance, diagnostic) and separately only for screening colonoscopies. Correlations were made using the Pearson's correlation coeficient. RESULTS: The sample was composed of 6925 patients over 50 years of age (3620 men, 3305 women, mean age 66.2 years). The ADRs for screening and surveillance were higher than for diagnostic colonoscopies for all of the endoscopists, and the ADRs for all colonoscopies were lower than for screening, but sufficiently over 25%. There was a positive correlation between the ADR of screening and all colonoscopies (r=0.906, P<0.005). CONCLUSIONS: The calculation of ADR for all colonoscopies was possible in our endoscopic department, and there was a positive correlation with ADR for screening colonoscopies. ADR for all colonoscopies is a good tool for calculating real ADR from large sample sizes without gaming. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03730441).
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Adenoma , Neoplasias Colorrectales , Adenoma/diagnóstico , Anciano , Colonoscopía , Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer , Femenino , Humanos , Masculino , Tamizaje Masivo , Estudios RetrospectivosRESUMEN
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 2nd study 292 tumor patients reported their pandemic-induced perceived changes and coping strategies by established questionnaires (WHO-5, MLQ, GrAw-7). An analysis of the HNC-data obtained by standardized questionnaires was performed. RESULTS: Study 1 had 91 HNC, study 2-84 HNC. Study 1 shows high stress levels for the majority of HNC (53,8â%). Personal fears regarding the own disease and therapies (39.6â%) are a central problem. The participants await physical (24.7â%) as well as psychological (21.3â%) consequences due to the pandemic and its current management. During the lockdown the isolation (banned visitors at any hospital) was discussed as critical main point by 58.5â% of HNC patients. Study 2 (after lockdown) underlined the mental stress caused by pandemic. Intensified relations within the families (58/100 points) as well as more intensive experience of nature and silence (58/60 points) are the most perceived changes in corona-times. HNC showed increased own inactivity (MLQ) and depressed well-being (WHO-5) and attention to the moment (GrAw-7). CONCLUSIONS: HNC patients have had high burden and fears due to the COVID-19 pandemic in spring 2020. Their views are important for further strategies to organize and stabilize the oncology service system during further pandemic periods.
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COVID-19 , Neoplasias de Cabeza y Cuello , Adaptación Psicológica , Control de Enfermedades Transmisibles , Neoplasias de Cabeza y Cuello/epidemiología , Neoplasias de Cabeza y Cuello/terapia , Humanos , Pandemias , SARS-CoV-2RESUMEN
Two Poaceae species, Agrostis capillaris and Festuca rubra, were selected for their potential as phytostabilizing plants in multicontaminated soils. These species are resistant to contamination and maintain high concentrations of contaminants at the root level. Nanoscale zero-valent iron (nZVI) is an engineered nanomaterial with the ability to stabilize metal(loid)s in soils; its potential toxicological effects in the selected species were studied in a germination test using: (i) control variant without soil; (ii) soil contaminated with Pb and Zn; and (iii) contaminated soil amended with 1% nZVI, as well as in an hydroponic experiment with the addition of nZVI 0, 25, 50 and 100 mg L-1. nZVI had no negative effects on seed germination or seedling growth, but was associated with an increase in shoot growth and reduction of the elongation inhibition rate (root-dependent) of F. rubra seedlings. However, applications of nZVI in the hydroponic solution had no effects on F. rubra but A. capillaris developed longer roots and more biomass. Increasing nZVI concentrations in the growing solution increased Mg and Fe uptake and reduced the Fe translocation factor. Our results indicate that nZVI has few toxic effects on the studied species.
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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. GASNGINAYL and SLWERLAYGI) were shown to bind high-resolution homology models of hNET in silico. In particular, one unique binding site has marked the sequence and structural similarities of both peptides, while most of the contribution to the interaction was attributed to the electrostatic energy of Asn and Arg (< - 228 kJ/mol). The peptides were comprehensively characterized by computational and spectroscopic methods showing ~ 21% ß-sheets/aggregation for GASNGINAYL and ~ 27% α-helix for SLWERLAYGI. After decorating 12-nm ferritin-based nanovehicles with cysteinated peptides, both peptides exhibited high potential for use in actively targeted neuroblastoma nanotherapy with exceptional in vitro biocompatibility and stability, showing minor yet distinct influences of the peptides on the global expression profiles. Upon binding to hNET with fast binding kinetics, GASNGINAYLC peptides enabled rapid endocytosis of ferritins into neuroblastoma cells, leading to apoptosis due to increased selective cytotoxicity of transported payload ellipticine. Peptide-coated nanovehicles significantly showed higher levels of early apoptosis after 6 h than non-coated nanovehicles (11% and 7.3%, respectively). Furthermore, targeting with the GASNGINAYLC peptide led to significantly higher degree of late apoptosis compared to the SLWERLAYGIC peptide (9.3% and 4.4%, respectively). These findings were supported by increased formation of reactive oxygen species, down-regulation of survivin and Bcl-2 and up-regulated p53. CONCLUSION: This novel homing nanovehicle employing GASNGINAYLC peptide was shown to induce rapid endocytosis of ellipticine-loaded ferritins into neuroblastoma cells in selective fashion and with successful payload. Future homing peptide development via lead optimization and functional analysis can pave the way towards efficient peptide-based active delivery of nanomedicines to neuroblastoma cells.
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Sistemas de Liberación de Medicamentos/métodos , Endocitosis/genética , Nanoestructuras/química , Neuroblastoma/metabolismo , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ferritinas/química , Humanos , Nanomedicina , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática/química , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática/genética , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática/metabolismo , Péptidos/química , Péptidos/genética , Péptidos/metabolismoRESUMEN
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). These lichens, post 4 h or 24 h of hydration, showed differences in their ChlF transients and values of major ChlF parameters, e.g., in the maximum quantum efficiency of PSII photochemistry (Fv/Fm), and yields of fluorescence and heat dissipation (Φf,d), of effective quantum efficiency of PSII photochemistry (ΦPSII) and of non-photochemical quenching (Φnpq), which may be due to quantitative and/or qualitative differences in the composition of their photobionts. For understanding the kinetics of hydration-induced activation of photosynthesis, we screened ΦPSII of these lichens and reported its non-linear stimulation on a minute time scale; half of the activation time (t1/2) was fastest ~4.05 ± 0.29 min for DP, which was followed by 5.46 ± 0.18 min for UA, and 13.95 ± 1.24 min for LP. Upon drying of fully activated lichen thallus, there was a slow decay, in hours, of relative water content (RWC) as well as of Fv/Fm. Raman spectral signatures were different for lichens having algal (in DP and UA) and cyanobacteria (in LP) photobionts, and there was a significant shift in ν1(C=C) Raman band of carotenoids post 24 h hydration as compared to their value at a dry state or post 4 h of hydration; this shift was decreased, when drying, in DP and LP but not in UA. We conclude that hydration nonlinearly activated photosynthetic apparatus/reactions of these lichens in minute time range but there was a de-novo synthesis of chlorophylls as well as of carotenoids post 24 h. Their dehydration-induced deactivation, however, was comparatively slow, in hours range, and there seemed a degradation of synthesized chlorophylls and carotenoids post dryness. We conclude that in extremophilic lichens, their photosynthetic partners, in particular, possess a complex survival and photoprotective strategy to be successful in the extreme terrestrial environments in Antarctica.
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Líquenes , Regiones Antárticas , Ascomicetos , Carotenoides/metabolismo , Clorofila , Clorofila A , Fluorescencia , Líquenes/metabolismo , Fotosíntesis , Espectrometría RamanRESUMEN
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. Antibacterial effect of RU-S4 was studied against Staphylococcus aureus (NCTC 8511), vancomycin-resistant Staphylococcus aureus (VRSA) (CCM 1767), methicillin-resistant Staphylococcus aureus (MRSA) (ST239: SCCmecIIIA), and hospital isolate Staphylococcus epidermidis. The antibacterial activity of RU-S4 was checked by growth curve analysis and the outcome was supported by optical microscopy imaging and fluorescence LIVE/DEAD cell imaging. In vivo (balb/c mice) infection model prepared with VRSA (CCM 1767) and treated with RU-S4. In our experimental conditions, all infected mice were cured. The interaction of coordination compound with bacterial cells were further confirmed by cryo-scanning electron microscope (Cryo-SEM). RU-S4 was completely non-toxic against mammalian cells and in mice and subsequently treated with synthesized RU-S4.
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Antibacterianos/química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Rutenio/química , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Espectrometría RamanRESUMEN
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. Raman imaging of these phototrophic colonization reveals a pigment composition within the aggregates that helps in understanding some of their adaptation strategies to survive in this harsh polyextreme environment. The study is focused on methodical aspects of Raman imaging acquisition and subsequent data processing. Point imaging is compared with line imaging in terms of their image quality, spatial resolution, spectral signal-to-noise ratio, time requirements, and risk of laser-induced sample alteration. The roles of excitation wavelength, exposure time, and step size of the imaging grid on successful Raman imaging results are also discussed. Graphical abstract.
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Cianobacterias/química , Microbiología del Suelo , Espectrometría Raman , Clima Desértico , Ecosistema , Pigmentos Biológicos/análisis , Espectrometría Raman/métodosRESUMEN
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 Chenopodium album. 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 a fluorescence (ChlF) and infrared thermal imaging. ChlF imaging show time-dependent transport in acropetal direction through veins and increase of area affected by metribuzin and demonstrated the ability to distinguish between fast processes at the level of electron transport (1 - Vj) from slow processes at the level of non-photochemical energy dissipation (NPQ) or maximum efficiency of PSII photochemistry (Fv/Fm). The high-resolution resonance Raman images show zones of local increase of carotenoid signal 72 h after the herbicide application, surrounding the damaged tissue, which points to the activation of defense mechanisms. The shift in the carotenoid band indicates structural changes in carotenoids. Finally, the increase of leaf temperature in the region surrounding the spot of herbicide application and expanding in the direction to the leaf tip proves the metribuzin effect on slow stomata closure.
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Clorofila A/metabolismo , Rayos Infrarrojos , Imagen Óptica , Complejo de Proteína del Fotosistema II/metabolismo , Hojas de la Planta/metabolismo , Espectrometría Raman , Temperatura , Chenopodium/fisiología , Fluorescencia , Procesamiento de Señales Asistido por Computador , Factores de TiempoRESUMEN
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 4â¯h, 24â¯h, and 48â¯h) of hydration, and compared the data obtained from this lichen in "dry state" as well as in different "hydrated state". We found that dry state of this lichen has: (1) no variable ChlF, (2) high reflectance, with no red-edge and almost zero photochemical reflectance index (PRI), and (3) low-intensity Raman bands of their carotenoids. Furthermore, 4â¯h of hydration, increased its relative water content (RWC) by 93%, showed red-edge in reflectance spectra, and changed the maximum quantum yield of PSII photochemistry (Fv/Fm) from 0 to 0.57⯱â¯0.01. We found that reflectance indices, normalized difference index (NDVI) and PRI, significantly differed between brown and black/green surface areas, at all hydration stages; whereas, a shift in the Raman ν1(CC) band, between brown and black/green surface areas, occurred in 24â¯h or 48â¯h hydrated samples. These data indicate that hydration shortly (within 4â¯h) activated functions of photosynthetic apparatus, and the de novo synthesis of carotenoids occured in 24â¯h or 48â¯h. Furthermore, exposure to high irradiance (2000⯵molâ¯photonsâ¯m-2â¯s-1), in 48â¯h hydrated lichen, significantly reduced Fv/Fm (signifies photoinhibition) and increased PRI (represents changes in xanthophyll pigments). We conclude that the implication of such a correlative approach is highly useful for understanding survival and protective mechanisms on extremophile photosynthetic organisms.
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Clorofila A/análisis , Líquenes/metabolismo , Espectrometría Raman , Agua/química , Fluorescencia , Fotosíntesis , Procesamiento de Señales Asistido por ComputadorRESUMEN
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). In this analysis, only patients from Czech Republic, Hungary, Poland and Serbia were included. The primary efficacy variable was the proportion of subjects achieving a physician global assessment (PGA) of psoriasis status: "clear" or "almost clear" at week 12. RESULTS: In the 307 patients, 54% BIW/QW compared with 40% (QW/QW) (p = .02), achieved "clear"/"almost clear" for PGA of psoriasis at week 12 increasing, to 68% and 60%, respectively (p = .134) by week 24. Mean improvement from baseline in PASI were 59% versus 49% (p = .005) at week 6 and 87% versus 81% (p < .05) at week 24, for the BIW/QW and QW/QW groups, respectively. ETN was well tolerated in both groups over 24 weeks. CONCLUSIONS: Both dose regimens of ETN provided significant improvements in efficacy in PsA treatment and were well tolerated.
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Artritis Psoriásica/tratamiento farmacológico , Etanercept/uso terapéutico , Psoriasis/tratamiento farmacológico , Adulto , Proteína C-Reactiva/análisis , Método Doble Ciego , Esquema de Medicación , Europa Oriental , Femenino , Humanos , Masculino , Persona de Mediana Edad , Piel/patología , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/antagonistas & inhibidoresRESUMEN
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. Change in the carotenoid composition (red-shift) within a transect through the cyanobacteria dominant microbial community (average thickness ~1 mm) was unambiguously revealed in their natural endolithic microhabitat. The amount of red shifted carotenoid, observed for the first time in a natural microbial ecosystem, is depth dependent, and increased with increasing proximity to the rock surface, as proven by resonance Raman imaging and point resonance Raman profiling. It is attributed to a light-dependent change in carotenoid conjugation, associated with the light-adaptation strategy of cyanobacteria. A hypothesis is proposed for the possible role of an orange carotenoid protein (OCP) mediated non-photochemical quenching (NPQ) mechanism that influences the observed spectral behavior. Simultaneously, information about the distribution of scytonemin and phycobiliproteins was obtained. Scytonemin was detected in the uppermost cyanobacteria aggregates. A reverse signal intensity gradient of phycobiliproteins was registered, increasing with deeper positions as a response of the cyanobacterial light harvesting complex to low-light conditions.
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Carotenoides/química , Cianobacterias , Clima Desértico , Carotenoides/metabolismo , Cianobacterias/aislamiento & purificación , Cianobacterias/metabolismo , Ecosistema , Microbiología Ambiental , Microscopía Confocal , Microscopía Fluorescente , Pigmentos Biológicos , Análisis EspectralRESUMEN
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. Strongly augmented relative content of phenolic compounds was observed in the case of amidosulfuron-treated plants, with a simultaneous decrease in the chlorophyll/carotenoid intensity ratio. The results were confirmed by in vivo measurement of flavonols using UV screening of ChlF. Herbicides from the group of carotenoid biosynthesis inhibitors significantly decreased both the maximum quantum efficiency of PSII and non-photochemical quenching as determined by ChlF. Resonance Raman imaging (mapping) data with high resolution (150,000-200,000 spectra) are presented, showing the distribution of carotenoids in H. annuus leaves treated by two of the herbicides acting as inhibitors of carotenoid biosynthesis (clomazone or diflufenican). Clear signs were observed that the treatment induced carotenoid depletion within sunflower leaves. The depletion spatial pattern registered differed depending on the type of herbicide applied.
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Clorofila/metabolismo , Helianthus/química , Herbicidas/toxicidad , Complejo de Proteína del Fotosistema II/química , Espectrometría Raman , Clorofila A , Flavonoles/análisis , Fluorescencia , Helianthus/efectos de los fármacos , Epidermis de la Planta/metabolismo , Hojas de la Planta/química , Estándares de ReferenciaRESUMEN
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. In this study, we characterized the basic properties and composition of quantum dots (QDs), obtained by the extracellular biosynthesis by Escherichia coli. Furthermore, the toxicity of the biosynthesized QDs was compared to QDs prepared by microwave synthesis. The obtained results revealed the presence of cyan CdTe QDs after removal of substantial amounts of organic compounds, which stabilized the nanoparticle surface. QDs toxicity was evaluated using three cell lines Human Foreskin Fibroblast (HFF), Human Prostate Cancer cells (PC-3) and Breast Cancer cells (MCF-7) and the MTT assay. The test revealed differences in the toxicity between variants of QDs, varying about 10% in the HFF and 30% in the MCF-7 cell lines. The toxicity of the biosynthesized QDs to the PC-3 cell lines was about 35% lower in comparison with the QDs prepared by microwave synthesis.
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Compuestos de Cadmio/toxicidad , Escherichia coli/metabolismo , Puntos Cuánticos/toxicidad , Telurio/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , HumanosRESUMEN
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. Colonoscopy still remains the gold standard for detection of colorectal neoplasias. In majority of countries worldwide programs for colorectal cancer screening are based on immunochemical fecal occult blood test followed by colonoscopy when positive.