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1.
Glob Chang Biol ; 30(4): e17279, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619007

RESUMO

There are close links between solar UV radiation, climate change, and plastic pollution. UV-driven weathering is a key process leading to the degradation of plastics in the environment but also the formation of potentially harmful plastic fragments such as micro- and nanoplastic particles. Estimates of the environmental persistence of plastic pollution, and the formation of fragments, will need to take in account plastic dispersal around the globe, as well as projected UV radiation levels and climate change factors.


Assuntos
Energia Solar , Raios Ultravioleta , Raios Ultravioleta/efeitos adversos , Mudança Climática , Poluição Ambiental , Tempo (Meteorologia)
2.
Photochem Photobiol Sci ; 23(4): 629-650, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38512633

RESUMO

This Assessment Update by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) considers the interactive effects of solar UV radiation, global warming, and other weathering factors on plastics. The Assessment illustrates the significance of solar UV radiation in decreasing the durability of plastic materials, degradation of plastic debris, formation of micro- and nanoplastic particles and accompanying leaching of potential toxic compounds. Micro- and nanoplastics have been found in all ecosystems, the atmosphere, and in humans. While the potential biological risks are not yet well-established, the widespread and increasing occurrence of plastic pollution is reason for continuing research and monitoring. Plastic debris persists after its intended life in soils, water bodies and the atmosphere as well as in living organisms. To counteract accumulation of plastics in the environment, the lifetime of novel plastics or plastic alternatives should better match the functional life of products, with eventual breakdown releasing harmless substances to the environment.


Assuntos
Plásticos , Poluentes Químicos da Água , Humanos , Plásticos/toxicidade , Ecossistema , Raios Ultravioleta , Mudança Climática , Poluentes Químicos da Água/análise
3.
Rev. toxicol ; 40(1): 45-52, ene.-jun. 2023. tab
Artigo em Inglês | IBECS | ID: ibc-222867

RESUMO

Food system is continuously exposed to several safety hazards throughout manufacturing processes. Consequently, the understanding of these mechanisms, the likelihood of their occurrence, and the consequences involves the implementation of an appropriate risk assessment program. Hazard Analysis and Safety Critical Control Points (HACCP) is a powerful tool for self-control system which is fundamental to adapt the requirements of each sector and size of a company but however, is currently limited it at industrial level. In fact, as a result to its flexible application, the recommendations at European level for companies with less than 10 workers focused on a food safety management system (FSMS) based on the principles of good hygiene and manufacturing practices. Therefore, in order to help companies implementing self-monitoring systems, several reference guides have been created under the supervision of health authorities. For this purpose, the aim of these study was to create an abbreviated guide as an introduction to self-control in food safety for spanish micro-enterprises. It is presented as a summary of each prerequisite focused solely on understanding the meaning and documentation necessary to implement it. To carry out the research, European legislation and the main guides at national level, particularly from autonomous communities were took into account. Starting from this information, was provided a classification of the main plans related to prerequisites for hygiene and traceability fulfilling. Moreover, indications concerning the documentation which should be prepared for each one of the prerequisites was detailed. (AU)


El sistema alimentario está continuamente expuesto a varios riesgos de seguridad a lo largo de los procesos de fabricación. En consecuencia, la comprensión de estos mecanismos, la probabilidad de su ocurrencia y las consecuencias implica la implementación de un programa adecuado de evaluación de riesgos. El Análisis de Peligros y Puntos Críticos de Control de Seguridad (APPCC) es una poderosa herramienta para el sistema de autocontrol que es fundamental para adaptar los requisitos de cada sector y tamaño de una empresa pero que, sin embargo, actualmente está limitado a nivel industrial. De hecho, como consecuencia de su aplicación flexible, las recomendaciones a nivel europeo para empresas de menos de 10 trabajadores se centraron en un sistema de gestión de la seguridad alimentaria (SGSA) basado en los principios de buenas prácticas de higiene y fabricación. Por ello, con el fin de ayudar a las empresas a implementar sistemas de autocontrol, se han elaborado varias guías de referencia bajo la supervisión de las autoridades sanitarias. Para ello, el objetivo de este estudio fue crear una guía abreviada como introducción al autocontrol en seguridad alimentaria para microempresas españolas. Se presenta como un resumen de cada requisito previo enfocado únicamente en comprender el significado y la documentación necesaria para implementarlo. Para realizar la investigación se tuvo en cuenta la legislación europea y las principales guías a nivel nacional, en particular de las comunidades autónomas. A partir de esta información, se proporcionó una clasificación de los principales planes relacionados con los requisitos previos para el cumplimiento de la higiene y la trazabilidad. Además, se detallaron indicaciones sobre la documentación que se debe preparar para cada uno de los requisitos previos. (AU)


Assuntos
Humanos , Abastecimento de Alimentos , Análise de Perigos e Pontos Críticos de Controle , Indústria Alimentícia , Medição de Risco , Espanha
4.
Photochem Photobiol Sci ; 22(9): 2055-2069, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37227683

RESUMO

Cyanobacteria are challenged by daily fluctuations of light intensities and photoperiod in their natural habitats, which affect the physiology and fitness of cyanobacteria. Circadian rhythms (CRs), an important endogenous process found in all organisms including cyanobacteria, control their physiological activities and helps in coping with 24-h light/dark (LD) cycle. In cyanobacteria, physiological responses under rhythmic ultraviolet radiation (UVR) are poorly studied. Therefore, we studied the changes in photosynthetic pigments, and physiological parameters of Synechocystis sp. PCC 6803 under UVR and photosynthetically active radiation (PAR) of light/dark (LD) oscillations having the combinations of 0, 4:20, 8:16, 12:12, 16:8, 20:4, and 24:24 h. The LD 16:8 enhanced the growth, pigments, proteins, photosynthetic efficiency, and physiology of Synechocystis sp. PCC6803. Continuous light (LL 24) of UVR and PAR exerted negative impact on the photosynthetic pigments, and chlorophyll fluorescence. Significant increase in reactive oxygen species (ROS) resulted in loss of plasma membrane integrity followed by decreased viability of cells. The dark phase played a significant role in Synechocystis to withstand the LL 24 under PAR and UVR. This study offers detailed understanding of the physiological responses of the cyanobacterium to changing light environment.


Assuntos
Synechocystis , Synechocystis/metabolismo , Raios Ultravioleta , Fotossíntese , Espécies Reativas de Oxigênio/metabolismo , Ritmo Circadiano , Proteínas de Bactérias/metabolismo
5.
Life (Basel) ; 13(1)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36676121

RESUMO

A biofilm is an aggregation of surface-associated microbial cells that is confined in an extracellular polymeric substance (EPS) matrix. Infections caused by microbes that form biofilms are linked to a variety of animals, including insects and humans. Antibiotics and other antimicrobials can be used to remove or eradicate biofilms in order to treat infections. However, due to biofilm resistance to antibiotics and antimicrobials, clinical observations and experimental research clearly demonstrates that antibiotic and antimicrobial therapies alone are frequently insufficient to completely eradicate biofilm infections. Therefore, it becomes crucial and urgent for clinicians to properly treat biofilm infections with currently available antimicrobials and analyze the results. Numerous biofilm-fighting strategies have been developed as a result of advancements in nanoparticle synthesis with an emphasis on metal oxide np. This review focuses on several therapeutic strategies that are currently being used and also those that could be developed in the future. These strategies aim to address important structural and functional aspects of microbial biofilms as well as biofilms' mechanisms for drug resistance, including the EPS matrix, quorum sensing (QS), and dormant cell targeting. The NPs have demonstrated significant efficacy against bacterial biofilms in a variety of bacterial species. To overcome resistance, treatments such as nanotechnology, quorum sensing, and photodynamic therapy could be used.

6.
Toxicol Mech Methods ; 33(3): 215-221, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36016515

RESUMO

Food and feed contamination by nonlegislated mycotoxins beauvericin (BEA) and enniatin B (ENB) is a worldwide health concern in the present. The principal objective of this work is to assess some of the existing protocols to discover the single nucleotide variants (SNVs) in transcriptomic data obtained by RNA-seq from Jurkat cells in vitro samples individually exposed to BEA and ENB at three concentration levels (1.5, 3 and 5 µM). Moreover, previous transcriptomic results will be compared with new findings obtained using a different protocol. SNVs rs201003509 in BEA exposed cells and the rs36045790 in ENB were found in the differentially expressed genes in all doses compared to controls by means of the Genome Analysis Toolkit (GATK) Best Practices workflow. SNV-RNA-seq complementary pipeline did not show any SNV. Concerning gene expression, discrepant results were found for 1.5 µM BEA exposed cells compared with previous findings. However, 354 overlapped differentially expressed genes (DEGs) were identified in the three ENB concentrations used, with 147 matches with respect to the 245 DEGs found in the previous results. In conclusion, the two discovery SNVs protocols based on variant calling from RNA-seq used in this work displayed very different results and there were SNVs found manually not identified by any pipeline. Additionally, the new gene expression analysis reported comparable but non identical DEGs to the previous transcriptomic results obtained from these RNA-seq data.


Assuntos
Micotoxinas , Humanos , Micotoxinas/toxicidade , RNA-Seq , Transcriptoma , Perfilação da Expressão Gênica , Nucleotídeos
7.
Biology (Basel) ; 11(11)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36358319

RESUMO

A chemical analysis of water quality cannot detect some toxicants due to time constraints, high costs, and limited interactions for detection. Bioassays would offer a complementary means to assess pollution levels in water. Euglena is a flagellate green alga and an excellent system for toxicity testing thanks to its ease of culture, rapid growth, and quick response to environmental stresses. Herein, we examined the sensitivity of E. agilis to seven heavy metals by analyzing six end-point parameters: motility, velocity, cell compactness, upward swimming, r-value, and alignment. Notably, the velocity of E. agilis was most sensitive to cadmium (96.28 mg·L-1), copper (6.51 mg·L-1), manganese (103.28 mg·L-1), lead (78.04 mg·L-1), and zinc (101.90 mg·L-1), while r-values were most sensitive to arsenic (12.84 mg·L-1) and mercury (4.26 mg·L-1). In this study, velocity and r-values are presented as useful biomarkers for the assessment of metal toxicity in Euglena. The metals As, Cd, Cu, and Pb were suitable for this test. The advantages of the ecotoxicity test are its rapidity: It takes 10 min to obtain results, as opposed to the typical 3-4 d of exposure time with intensive labor. Moreover, this test can be performed at room temperature under dark conditions.

8.
Anticancer Res ; 42(10): 5035-5041, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36191985

RESUMO

Photosynthesis is the basis of almost all life on Earth. In addition to providing energy, plants and algae provide a plethora of secondary substances useful in the treatment of a number of illnesses including a wide array of cancer maladies. The first organisms on Earth used chemosynthesis for their energy needs. Photosynthetic bacteria utilize one of two different photosystems whereas cyanobacteria, eukaryotic algae and plants combine two photosystems in a linear electron transport chain. Accessory pigments such as various chlorophylls, carotenoids and phycobilins absorb the energy of impinging photons and funnel it to the reaction centers (P680 in photosystem II and P700 in photosystem I). Water is split photochemically, electrons are transported to reduce NADPH, oxygen is discarded as waste product, and protons accumulate inside the thylakoid vesicles in the chloroplasts. The resulting electrochemical gradient across the membrane is used to drive an ATPase. The produced ATP and NADPH+H+ are utilized in the Calvin cycle to fix CO2 and to produce fructose.


Assuntos
Complexo de Proteína do Fotossistema I , Complexo de Proteína do Fotossistema II , Adenosina Trifosfatases , Trifosfato de Adenosina , Dióxido de Carbono , Carotenoides , Transporte de Elétrons , Frutose , NADP , Oxigênio/metabolismo , Fotossíntese , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Ficobilinas , Prótons , Água
9.
Life (Basel) ; 12(10)2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36294957

RESUMO

Human exploration of space and other celestial bodies bears a multitude of challenges. The Earth-bound supply of material and food is restricted, and in situ resource utilisation (ISRU) is a prerequisite. Excellent candidates for delivering several services are unicellular algae, such as the space-approved flagellate Euglena gracilis. This review summarizes the main characteristics of this unicellular organism. Euglena has been exposed on various platforms that alter the impact of gravity to analyse its corresponding gravity-dependent physiological and molecular genetic responses. The sensory transduction chain of gravitaxis in E. gracilis has been identified. The molecular gravi-(mechano-)receptors are mechanosensory calcium channels (TRP channels). The inward gated calcium binds specifically to one of several calmodulins (CaM.2), which, in turn, activates an adenylyl cyclase. This enzyme uses ATP to produce cAMP, which induces protein kinase A, followed by the phosphorylation of a motor protein in the flagellum, initiating a course correction, and, finally, resulting in gravitaxis. During long space missions, a considerable amount of food, oxygen, and water has to be carried, and the exhaled carbon dioxide has to be removed. In this context, E. gracilis is an excellent candidate for biological life support systems, since it produces oxygen by photosynthesis, takes up carbon dioxide, and is even edible. Various species and mutants of Euglena are utilized as a producer of commercial food items, as well as a source of medicines, as it produces a number of vitamins, contains numerous trace elements, and synthesizes dietary proteins, lipids, and the reserve molecule paramylon. Euglena has anti-inflammatory, -oxidant, and -obesity properties.

10.
Food Chem Toxicol ; 158: 112661, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34762978

RESUMO

The world requests for raw materials used in animal feed has been steadily rising in the last years driven by higher demands for livestock production. Mycotoxins are frequent toxic metabolites present in these raw materials. The exposure of farm animals to mycotoxins could result in undesirable residues in animal-derived food products. Thus, the potential ingestion of edible animal products (milk, meat and fish) contaminated with mycotoxins constitutes a public health concern, since they enter the food chain and may cause adverse effects upon human health. The present review summarizes the state-of-the-art on the occurrence of mycotoxins in feed, their metabolism and carry-over into animal source foodstuffs, focusing particularly on the last decade. Maximum levels (MLs) for various mycotoxins have been established for a number of raw feed materials and animal food products. Such values are sometimes exceeded, however. Aflatoxins (AFs), fumonisins (FBs), ochratoxin A (OTA), trichothecenes (TCs) and zearalenone (ZEN) are the most prevalent mycotoxins in animal feed, with aflatoxin M1 (AFM1) predominating in milk and dairy products, and OTA in meat by-products. The co-occurrence of mycotoxins in feed raw materials tends to be the rule rather than the exception, and the carry-over of mycotoxins from feed to animal source foods is more than proven.


Assuntos
Ração Animal/análise , Contaminação de Alimentos/análise , Carne/análise , Micotoxinas/análise , Animais , Contaminação de Alimentos/estatística & dados numéricos
11.
Food Funct ; 12(22): 11250-11261, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34708849

RESUMO

Microbial fermentation with lactic acid bacteria (LAB) is a natural food biopreservation method. Yellow mustard and milk whey are optimum substrates for LAB fermentation. The aim of the present study was to evaluate the bioaccessibility and bioavailability of bioactive compounds from yellow mustard flour and milk whey both with and without LAB fermentation. All extracts were subjected to a simulated digestion process. Total polyphenols, DL-3-phenyllactic acid (PLA), lactic acid, and the antioxidant activity were determined in the studied matrices before and after simulated digestion. Yellow mustard flour was significantly richer in total polyphenols, whereas significantly higher concentrations of PLA and lactic acid were observed in milk whey. Similar antioxidant activity was determined in both ingredients being in all cases strongly reduced after in vitro digestion. Higher bioaccessibility was found for polyphenols and PLA in milk whey. Transepithelial transport of total polyphenols was higher in yellow mustard flour compared to milk whey, reaching bioavailability values between 3-7% and 1-2%, respectively. PLA transepithelial transport was only significant in both fermented matrices with bioavailability around 4-6%. Transepithelial transport of lactic acid reached values of 31-34% (bioavailability ∼ 22%) and 15-78% (bioavailability ∼ 3%) in milk whey and yellow mustard flour, respectively. LAB fermentation showed beneficial effects on enriching extracts with PLA, lactic acid, and antioxidant activity, as well as increasing bioaccessibility of these acids in yellow mustard flour and total polyphenol bioavailability in milk whey. Results pointed to yellow mustard flour and milk whey as natural preservative ingredients used in the food industry, especially when fermented with LAB.


Assuntos
Antioxidantes , Lactobacillales/metabolismo , Leite/metabolismo , Mostardeira/química , Soro do Leite/metabolismo , Animais , Antioxidantes/química , Antioxidantes/farmacocinética , Disponibilidade Biológica , Células CACO-2 , Fermentação/fisiologia , Humanos , Lactatos/química , Lactatos/farmacocinética , Ácido Láctico/química , Ácido Láctico/farmacocinética
12.
3 Biotech ; 11(1): 10, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33442509

RESUMO

This study summarizes the response of a hot spring cyanobacterium Fischerella sp. strain HKAR-14, under simulated light conditions of ultraviolet radiation (UVR), photosynthetically active radiation (PAR), PAR + UV-A (PA) and PAR + UV-A + UV-B (PAB). Exposure to UVR caused a decline in growth and Chl a while total carotene content increased under PA and PAB. Maximum photochemical efficiency of photosystem II (F v /F m) and relative electron transport rate decreased significantly in PA and PAB exposure. Higher non-photochemical quenching and lower photochemical quenching values were observed in UVR-exposed samples as compared to the control. Levels of intracellular reactive oxygen species (ROS) increased significantly in PAB and PA. Fluorescence microscopic images showed an increase in green fluorescence, indicating the generation of ROS in UVR. The antioxidant machinery including superoxide dismutase, catalase and peroxidase showed an increase of 1.76-fold and 2.5-fold superoxide dismutase, 2.4-fold and 3.7-fold catalase, 1.83-fold and 2.5-fold peroxidase activities under PA and PAB, respectively. High-performance liquid chromatography equipped with photodiode array detector, electrospray ionization mass spectrometry, Fourier-transform infrared spectroscopy and nuclear magnetic resonance spectroscopy analyses reveal the occurrence of a single mycosporine-like amino acid, shinorine (λ max 332.3 ± 2 nm, m/z 333.1), with a retention time of 1.157 min. The electrochemical characterization of shinorine was determined by cyclic voltammetry. The shinorine molecule possesses electrochemical activity and represents diffusion-controlled process in 0.1 M (pH 7.0) phosphate buffer. An antioxidant assay of shinorine showed its efficient activity as antioxidant which increased in a dose-dependent manner.

13.
Sci Total Environ ; 713: 136586, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31955090

RESUMO

Aquatic ecosystems cover over two thirds of our planet and play a pivotal role in stabilizing the global climate as well as providing a large array of services for a fast-growing human population. However, anthropogenic activities increasingly provoke deleterious impacts in aquatic ecosystems. In this paper we discuss five sources of anthropogenic pollution that affect marine and freshwater ecosystems: sewage, nutrients and terrigenous materials, crude oil, heavy metals and plastics. Using specific locations as examples, we show that land-based anthropogenic activities have repercussions in freshwater and marine environments, and we detail the direct and indirect effects that these pollutants have on a range of aquatic organisms, even when the pollutant source is distant from the sink. While the issues covered here do focus on specific locations, they exemplify emerging problems that are increasingly common around the world. All these issues are in dire need of stricter environmental policies and legislations particularly for pollution at industrial levels, as well as solutions to mitigate the effects of anthropogenic pollutants and restore the important services provided by aquatic ecosystems for future generations.

14.
Rev. toxicol ; 37(2): 106-110, 2020. tab
Artigo em Inglês | IBECS | ID: ibc-199309

RESUMO

Mycotoxins are common toxic metabolites present in cereals and vegetal raw materials, which are commonly included in animal feed. Ochratoxin A (OTA) has generally been detected in plant origin foodstuffs such as cereals, coffee, dried fruits, nuts, among others. However, it has been also detected in meat and meat by-products, especially those derived from pork, which is the most sensitive specie to OTA exposure. The exposure of farm animals to mycotoxins could lead to undesirable residues in food products of animal origin, which constitute an important part of daily diets. Thus, although contents reported in animal by-products are lower than those reported in products of vegetal origin, there is also a public health concern about the possible ingestion of edible animal products contaminated by mycotoxins, as their entry into the food chain may cause adverse effects on human health. No maximum levels have been set for OTA in animal by-products, although its presence in meat and meat products made from contaminated raw materials has been widely reported, reaching high levels in some cases. This review summarizes the state-of-the-art on the occurrence and the carry-over of OTA in meat products, especially focused on the last years


No disponible


Assuntos
Animais , Carne/análise , Ocratoxinas/análise , Contaminação de Alimentos
15.
Sci Total Environ ; 682: 239-246, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31121350

RESUMO

Aquatic and terrestrial organisms are being exposed to a number of anthropogenically-induced environmental stresses as a consequence of climate change. In addition, climate change is altering various linkages that exist between ecosystems on land and in water. Here we compare and contrast how climate change is altering aquatic and terrestrial environments and address some of the ways that the organisms in these ecosystems, especially the primary producers, are being affected by climate change factors, including changes in temperature, moisture, atmospheric carbon dioxide and solar UV radiation. Whereas there are some responses to climate change in common between terrestrial and aquatic ecosystems (e.g., changes in species composition and shifting geographic ranges and distributions), there are also responses that fundamentally differ between these two (e.g., responses to UV radiation). Climate change is also disrupting land-water connections in ways that influence biogeochemical and hydrologic cycles, and biosphere-atmosphere interactions in ways that can modify how aquatic and terrestrial ecosystems are affected by climate change and can influence climate change. The effects of climate change on these ecosystems are having wide-ranging effects on ecosystem biodiversity, structure and function and the abilities of these systems to provide essential services.


Assuntos
Mudança Climática , Ecossistema , Biodiversidade
16.
Photochem Photobiol Sci ; 18(3): 717-746, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30810561

RESUMO

This assessment summarises the current state of knowledge on the interactive effects of ozone depletion and climate change on aquatic ecosystems, focusing on how these affect exposures to UV radiation in both inland and oceanic waters. The ways in which stratospheric ozone depletion is directly altering climate in the southern hemisphere and the consequent extensive effects on aquatic ecosystems are also addressed. The primary objective is to synthesise novel findings over the past four years in the context of the existing understanding of ecosystem response to UV radiation and the interactive effects of climate change. If it were not for the Montreal Protocol, stratospheric ozone depletion would have led to high levels of exposure to solar UV radiation with much stronger negative effects on all trophic levels in aquatic ecosystems than currently experienced in both inland and oceanic waters. This "world avoided" scenario that has curtailed ozone depletion, means that climate change and other environmental variables will play the primary role in regulating the exposure of aquatic organisms to solar UV radiation. Reductions in the thickness and duration of snow and ice cover are increasing the levels of exposure of aquatic organisms to UV radiation. Climate change was also expected to increase exposure by causing shallow mixed layers, but new data show deepening in some regions and shoaling in others. In contrast, climate-change related increases in heavy precipitation and melting of glaciers and permafrost are increasing the concentration and colour of UV-absorbing dissolved organic matter (DOM) and particulates. This is leading to the "browning" of many inland and coastal waters, with consequent loss of the valuable ecosystem service in which solar UV radiation disinfects surface waters of parasites and pathogens. Many organisms can reduce damage due to exposure to UV radiation through behavioural avoidance, photoprotection, and photoenzymatic repair, but meta-analyses continue to confirm negative effects of UV radiation across all trophic levels. Modeling studies estimating photoinhibition of primary production in parts of the Pacific Ocean have demonstrated that the UV radiation component of sunlight leads to a 20% decrease in estimates of primary productivity. Exposure to UV radiation can also lead to positive effects on some organisms by damaging less UV-tolerant predators, competitors, and pathogens. UV radiation also contributes to the formation of microplastic pollutants and interacts with artificial sunscreens and other pollutants with adverse effects on aquatic ecosystems. Exposure to UV-B radiation can decrease the toxicity of some pollutants such as methyl mercury (due to its role in demethylation) but increase the toxicity of other pollutants such as some pesticides and polycyclic aromatic hydrocarbons. Feeding on microplastics by zooplankton can lead to bioaccumulation in fish. Microplastics are found in up to 20% of fish marketed for human consumption, potentially threatening food security. Depletion of stratospheric ozone has altered climate in the southern hemisphere in ways that have increased oceanic productivity and consequently the growth, survival and reproduction of many sea birds and mammals. In contrast, warmer sea surface temperatures related to these climate shifts are also correlated with declines in both kelp beds in Tasmania and corals in Brazil. This assessment demonstrates that knowledge of the interactive effects of ozone depletion, UV radiation, and climate change factors on aquatic ecosystems has advanced considerably over the past four years and confirms the importance of considering synergies between environmental factors.


Assuntos
Adaptação Biológica , Organismos Aquáticos/fisiologia , Mudança Climática , Perda de Ozônio , Raios Ultravioleta , Animais , Aquicultura , Organismos Aquáticos/efeitos da radiação , Ecossistema , Poluição Ambiental/efeitos adversos , Poluição Ambiental/análise , Peixes/fisiologia , Água Doce/análise , Camada de Gelo/química , Oceanos e Mares , Fotossíntese , Ozônio Estratosférico/análise , Raios Ultravioleta/efeitos adversos , Zooplâncton/fisiologia
17.
Front Plant Sci ; 10: 1621, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31969888

RESUMO

For long-term manned interplanetary missions it is not feasible to carry the necessary oxygen, food, and water to sustain the astronauts. In addition, the CO2 exhaled by the astronauts has to be removed from the cabin air. One alternative is to utilize photosynthetic organisms to uptake the CO2 and produce oxygen. In addition to higher plants, algae are perfect candidates for this purpose. They also serve to absorb wastes and clean the water. Cyanobacteria can be utilized as food supplement. Early ground-based systems include micro-ecological life support system alternative, closed equilibrated biological aquatic system, and the Biomass Production Chamber. The AQUARACK used the unicellular flagellate Euglena which produced the oxygen for fish in a connected compartment. A number of bioregenerative systems (AQUACELLS, OMEGAHAB) have been built for experiments on satellites. A later experiment was based on a 60-ml closed aquatic ecosystem launched on the Shenzhou 8 spacecraft containing several algae and a small snail living in adjacent chambers. Recently the Eu : CROPIS mission has been launched in a small satellite within a Deutschen Zentrum für Luft- und Raumfahrt (DLR) program. In addition to tomato plants, Euglena is included as oxygen producer. One new approach is to recycle urine on a bacterial filter to produce nitrogen fertilizer to grow vegetables.

18.
Int J Biol Sci ; 14(7): 784-790, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29910688

RESUMO

We have suggested that papillary renal cell tumor (PRCT) of the kidney arises from nephrogenic rest-like lesions. To approve our hypothesis, we worked up 14 kidneys bearing papillary and 14 ones with conventional renal cell carcinoma (CRCC) histologically and found 42 papillary lesions in average per kidney bearing PRCT. PRCTs are characterized by loss of the Y chromosome and trisomy of chromosomes 7 and 17. The MET and HNF1B are localized to chromosome 7q31 and 17q21 and are frequently amplified in PRCT. We have analyzed the expression of the mutant MET in hereditary PRCTs and precursor lesions and found duplication and expression of the mutated allele. Because both genes are involved in early stage of nephron development, we have analyzed the expression of MET and HNF1B by immunohistochemistry in fetal kidneys, precursor lesions and PRCTs. We detected strong expression of MET and HNF1B in distal compartment of S-shaped body of fetal kidneys and in nephrogenic rest-like precursor lesions. Our finding suggests an association between expression of MET and HNF1B in precursor lesions and development of PRCT. We propose a model involving chromosomal clonal evolution and corresponding gene expression for development of PRCTs from embryonic rests due to impaired differentiation. Our model suggests that PRCT have a natural history distinct from that of most common CRCC.


Assuntos
Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Alelos , Carcinogênese/genética , Carcinogênese/patologia , Transformação Celular Neoplásica/genética , Feminino , Fator 1-beta Nuclear de Hepatócito/genética , Fator 1-beta Nuclear de Hepatócito/metabolismo , Humanos , Rim/metabolismo , Masculino
19.
Food Chem Toxicol ; 114: 246-259, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29476792

RESUMO

Contamination of animal feed with mycotoxins still occurs very often, despite great efforts in preventing it. Animal feeds are contaminated, at low levels, with several mycotoxins, particularly with those produced by Aspergillus and Fusarium genera (Aflatoxin B1, Ochratoxin A, Zearalenone, Deoxynivalenol and Fumonisina B1). In animal feed, to date, only Aflatoxin B1 is limited through EU regulation. Consequently, mycotoxins cause serious disorders and diseases in farm animals. In 2009, the European Union (386/2009/EC) approved the use of mycotoxin-detoxifying agents, as feed additives, to prevent mycotoxicoses in farm animals. The present review gives an overview of the problem of multi-mycotoxin contamination of feed, and aims to classify mycotoxin adsorbing agents (minerals, organic, and synthetic) for feed decontamination, focusing on adsorbents with the ability to bind to multiple mycotoxins, which should have a more effective application in farms but they are still little studied in scientific literature.


Assuntos
Ração Animal/análise , Descontaminação/métodos , Micotoxinas/química , Adsorção , Animais , Descontaminação/instrumentação , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Micotoxinas/isolamento & purificação
20.
NPJ Microgravity ; 3: 13, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28649635

RESUMO

We have selected five evolutionary very different biological systems ranging from unicellular protists via algae and higher plants to human cells showing responses to the gravity vector of the Earth in order to compare their graviperception mechanisms. All these systems use a mass, which may either by a heavy statolith or the whole content of the cell heavier than the surrounding medium to operate on a gravireceptor either by exerting pressure or by pulling on a cytoskeletal element. In many cases the receptor seems to be a mechanosensitive ion channel activated by the gravitational force which allows a gated ion flux across the membrane when activated. This has been identified in many systems to be a calcium current, which in turn activates subsequent elements of the sensory transduction chain, such as calmodulin, which in turn results in the activation of ubiquitous enzymes, gene expression activation or silencing. Naturally, the subsequent responses to the gravity stimulus differ widely between the systems ranging from orientational movement and directed growth to physiological reactions and adaptation to the environmental conditions.

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