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1.
J Sci Food Agric ; 104(4): 2314-2325, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-37950679

RESUMO

BACKGROUND: Botrytis cinerea (Bc) is the causative agent of gray mold disease in wine grape bunches. Under particular climatic and edaphic conditions, typical of some wine regions, the grapes infected by this fungus can develop noble rot, the basic phenomenon for the production of sweet botrytized wines or some high-quality dry wines, such as Amarone. The possibility of early detection of noble rot on plants and at postharvest is an interesting option for managing botrytized wines. RESULTS: The present work aimed at early detection of noble rot and monitoring its development, at postharvest, on Trebbiano wine grapes by means of destructive and non-destructive analytical approaches (e.g., electronic nose and near-infrared spectroscopy). The development of Bc led to substantial modifications in grape composition, including dehydration, biosynthesis, and accumulation of different compounds due to Bc metabolism, grape stress responses, or both. However, these modifications are appreciable, notably at advanced stages of infection. Consequently, a specific focus was to monitor the infection in the first 72 h post inoculation for testing, potentially through non-destructive technologies, and to identify the real early stages of Bc development. CONCLUSION: The destructive chemical analyses performed over the 16 monitored days confirmed what is widely reported in the literature regarding the metabolic/compositional changes that occur following the development of Bc. Moreover, non-destructive technologies allowed us to identify the evolution of Bc, even at early stages of its presence. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Vitis , Vinho , Vitis/química , Vinho/análise , Botrytis/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho , Frutas/química
2.
J Pharmacol Exp Ther ; 373(1): 62-71, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31941719

RESUMO

The present study used human myeloid leukemia U937 cells, a versatile promonocytic cellular system that, based on its endoplasmic reticulum (ER)/mitochondria functional relationships, responds to low micromolar concentrations of arsenite with a single, defined mechanism of superoxide (O2 -.) formation. Under these conditions, we observe an initial Ca2+ mobilization from the ER associated with the mitochondrial accumulation of the cation, which is followed by Ca2+-dependent mitochondrial O2 -. (mitoO2 -.) formation. These events, which were barely detectable after 3 hours, were better appreciated at 6 hours. We found that markedly shorter exposure to arsenite and lower concentrations of arsenite are required to induce extensive O2 - formation in cells supplemented with inositol-1,4,5-trisphosphate receptor (IP3R) or ryanodine receptor (RyR) agonists. Indeed, nanomolar arsenite induced maximal O2 -. formation after only 10 minutes of exposure, and this response was uniquely dependent on the enforced mitochondrial Ca2+ accumulation. The dramatic anticipation of and sensitization to the effects of arsenite caused by the IP3R or RyR agonists were accompanied by a parallel significant genotoxic response in the absence of detectable mitochondrial dysfunction and cytotoxicity. We conclude that the prolonged, low-micromolar arsenite exposure paradigm resulting in mitoO2 -. formation is necessary to affect Ca2+ homeostasis and accumulate the cation in mitochondria. The arsenite requirements to promote mitoO2 -. formation in the presence of sufficient mitochondrial Ca2+ were instead remarkably lower in terms of both concentration and time of exposure. These conditions were associated with the induction of extensive DNA strand scission in the absence of detectable signs of toxicity. SIGNIFICANCE STATEMENT: In respiration-proficient cells, arsenite causes mitochondrial Ca2+ accumulation and Ca2+-dependent mitochondrial superoxide formation. We now report that the second event requires remarkably lower concentrations of and time of exposure to the metalloid than the former. Indeed, a brief exposure to nanomolar levels of arsenite produced maximal effects under conditions in which the mitochondrial Ca2+ concentration ([Ca2+]m) was increased by inositol-1,4,5-trisphosphate receptor or ryanodine receptor agonists. Hence, specific substances or conditions enhancing the [Ca2+]m may potentiate the deleterious effects of arsenite by selectively increasing mitochondrial superoxide formation.


Assuntos
Arsenitos/toxicidade , Retículo Endoplasmático/efeitos dos fármacos , Metaloides/toxicidade , Mitocôndrias/efeitos dos fármacos , Superóxidos , Teratogênicos/toxicidade , Relação Dose-Resposta a Droga , Retículo Endoplasmático/metabolismo , Humanos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxidos/metabolismo , Fatores de Tempo , Células U937
3.
Biochem Pharmacol ; 198: 114973, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35189109

RESUMO

Arsenite, a well-established human carcinogen and toxic compound, promotes the formation of mitochondrial superoxide (mitoO2-) via a Ca2+-dependent mechanism, in which an initial stimulation of the inositol 1, 4, 5-trisphosphate receptor (IP3R) is followed by the activation of the ryanodine receptor (RyR), critical for providing Ca2+ to the mitochondria. We now report that, under the same conditions, arsenite triggers endoplasmic reticulum (ER) stress and a threefold increase in ER oxidoreductin 1α (ERO1 α) levels in proliferating U937 cells. EN460, an inhibitor of ERO1 α, recapitulated all the effects associated with RyR inhibition or downregulation, including prevention of RyR-induced Ca2+ accumulation in mitochondria and the resulting O2-. formation. Quantitatively similar results were obtained in inhibitor studies performed in terminally differentiated wild type C2C12 cells. Moreover, ERO1 α knockout C2C12 myotubes responded to arsenite as their wild type counterpart supplemented with EN460. As a final note, arsenite enhanced the expression of ERO1 α via a mechanism mediated by Ca2+ release from both the IP3R and RyR. We therefore conclude that arsenite activates a positive feedback amplification cycle between Ca2+ levels and ERO1 α in the ER, by which IP3R-dependent Ca2+ induces ERO1 α and ERO1 α promotes Ca2+ release via RyR, thereby amplifying the initial Ca2+ load and causing the mitochondrial accumulation of the cation, critical for mitoO2- formation.


Assuntos
Sinalização do Cálcio , Glicoproteínas de Membrana , Oxirredutases , Canal de Liberação de Cálcio do Receptor de Rianodina , Arsenitos/efeitos adversos , Cálcio/metabolismo , Humanos , Glicoproteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Oxirredutases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Células U937
4.
BMJ Open ; 11(7): e046364, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34244263

RESUMO

OBJECTIVE: Countries have major differences in the acceptance of face mask use for the prevention of COVID-19. This work aims at studying the information online in different countries in terms of information quality and content. DESIGN: Content analysis. METHOD: We analysed 450 webpages returned by searching the string 'are face masks dangerous' in Italy, the UK and the USA using three search engines (Bing, Duckduckgo and Google) in August 2020. The type of website and the stance about masks were assessed by two raters for each language and inter-rater agreement reported as Cohen's kappa. The text of the webpages was collected from the web using WebBootCaT and analysed using a corpus analysis software to identify issues mentioned. RESULTS: Most pages were news outlets, and few (2%-6%) from public health agencies. Webpages with a negative stance on masks were more frequent in Italian (28%) than English (19%). Google returned the highest number of mask-positive pages and Duckduckgo the lowest. Google also returned the lowest number of pages mentioning conspiracy theories and Duckduckgo the highest. Webpages in Italian scored lower than those in English in transparency (reporting authors, their credentials and backing the information with references). When issues about the use of face masks were analysed, mask effectiveness was the most discussed followed by hypercapnia (accumulation of carbon dioxide), contraindication in respiratory disease and hypoxia, with issues related to their contraindications in mental health conditions and disability mentioned by very few pages. CONCLUSIONS: This study suggests that: (1) public health agencies should increase their web presence in providing correct information on face masks; (2) search engines should improve the information quality criteria in their ranking; (3) the public should be more informed on issues related to the use of masks and disabilities, mental health and stigma arising for those people who cannot wear masks.


Assuntos
COVID-19 , Ferramenta de Busca , Humanos , Internet , Itália , Idioma , Máscaras , SARS-CoV-2
5.
Food Chem Toxicol ; 156: 112523, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34453993

RESUMO

Arsenite induces many critical effects associated with the formation of reactive oxygen species (ROS) through different mechanisms. We focused on Ca2+-dependent mitochondrial superoxide (mitoO2-.) formation and addressed questions on the effects of low concentrations of arsenite on the mobilization of the cation from the endoplasmic reticulum and the resulting mitochondrial accumulation. Using various differentiated and undifferentiated cell types uniquely expressing the inositol-1, 4, 5-triphosphate receptor (IP3R), or both the IP3R and the ryanodine receptor (RyR), we determined that expression of this second Ca2+ channel is an absolute requirement for mitoO2-. formation and for the ensuing mitochondrial dysfunction and downstream apoptosis. In arsenite-treated cells, RyR was recruited after IP3R stimulation and agonist studies provided an indirect indication for a close apposition between RyR and mitochondria. It was also interesting to observe that arsenite fails to promote mitochondrial Ca2+ accumulation, mitoO2-. formation and mitochondrial toxicity in RyR-devoid cells, in which the IP3R is in close contact with the mitochondria. We therefore conclude that low dose arsenite-induced mitoO2- formation, and the resulting mitochondrial dysfunction and toxicity, are prerequisite of cell types expressing the RyR in close apposition with mitochondria.


Assuntos
Arsenitos/toxicidade , Retículo Endoplasmático/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Superóxidos/metabolismo , Apoptose , Cálcio/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Retículo Endoplasmático/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo
6.
Cell Signal ; 70: 109591, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32126264

RESUMO

The main hallmark of many forms of familiar and sporadic amyotrophic lateral sclerosis (ALS) is a reduction in nuclear TDP-43 protein and its inclusion in cytoplasmic aggregates in motor neurons. In order to understand which cellular and molecular mechanisms underlie the mislocalization of TDP-43, we examined human skin fibroblasts from two individuals with familial ALS, both with mutations in TDP-43, and two individuals with sporadic ALS, both without TDP-43 mutations or mutations in other ALS related genes. We found that all ALS fibroblasts had a partially cytoplasmic localization of TDP-43 and had reduced cell metabolism as compared to fibroblasts from apparently healthy individuals. ALS fibroblasts showed an increase in global protein synthesis and an increase in 4E-BP1 and rpS6 phosphorylation, which is indicative of mTORC1 activity. We also observed a decrease in glutathione (GSH), which suggests that oxidative stress is elevated in ALS. ERK1/2 activity regulated the extent of oxidative stress and the localization of TDP-43 in the cytoplasm in all ALS fibroblasts. Lastly, ALS fibroblasts showed reduced stress granule formation in response to H2O2 stress. In conclusion, these findings identify specific cellular and molecular defects in ALS fibroblasts, thus providing insight into potential mechanisms that may also occur in degenerating motor neurons.


Assuntos
Esclerose Lateral Amiotrófica , Proteínas de Ligação a DNA/metabolismo , Fibroblastos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Pele , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Células Cultivadas , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Estresse Oxidativo , Pele/metabolismo , Pele/patologia
7.
Front Med (Lausanne) ; 7: 400, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32850905

RESUMO

The fact that Internet companies may record our personal data and track our online behavior for commercial or political purpose has emphasized aspects related to online privacy. This has also led to the development of search engines that promise no tracking and privacy. Search engines also have a major role in spreading low-quality health information such as that of anti-vaccine websites. This study investigates the relationship between search engines' approach to privacy and the scientific quality of the information they return. We analyzed the first 30 webpages returned searching "vaccines autism" in English, Spanish, Italian, and French. The results show that not only "alternative" search engines (Duckduckgo, Ecosia, Qwant, Swisscows, and Mojeek) but also other commercial engines (Bing, Yahoo) often return more anti-vaccine pages (10-53%) than Google.com (0%). Some localized versions of Google, however, returned more anti-vaccine webpages (up to 10%) than Google.com. Health information returned by search engines has an impact on public health and, specifically, in the acceptance of vaccines. The issue of information quality when seeking information for making health-related decisions also impact the ethical aspect represented by the right to an informed consent. Our study suggests that designing a search engine that is privacy savvy and avoids issues with filter bubbles that can result from user-tracking is necessary but insufficient; instead, mechanisms should be developed to test search engines from the perspective of information quality (particularly for health-related webpages) before they can be deemed trustworthy providers of public health information.

8.
Ann Chim ; 96(11-12): 743-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17217178

RESUMO

The chemical and trophic conditions of the surface waters of the lake Bracciano, near Roma, have been investigated all through the year 2005. Electrical conductivity, pH, alkalinity, hardness, total nitrogen, phosphorus content, chloride, fluoride and sulphate ions were measured. The results were compared with similar analyses formerly carried out by different authors, to achieve a right evaluation of the actual quality of the surface waters of the lake Bracciano all over the year 2005.


Assuntos
Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Cloretos/análise , Condutividade Elétrica , Monitoramento Ambiental , Fluoretos/análise , Água Doce/análise , Concentração de Íons de Hidrogênio , Itália , Nitrogênio/análise , Fósforo/análise , Sulfatos/análise , Poluição da Água/análise
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