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1.
Biomedicines ; 11(12)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38137537

RESUMO

Zika virus (ZIKV) has emerged as a significant public health threat, reaching pandemic levels in 2016. Human infection with ZIKV can manifest as either asymptomatic or as an acute illness characterized by symptoms such as fever and headache. Moreover, it has been associated with severe neurological complications in adults, including Guillain-Barre syndrome, and devastating fetal abnormalities, like microcephaly. The primary mode of transmission is through Aedes spp. mosquitoes, and with half of the world's population residing in regions where Aedes aegypti, the principal vector, thrives, the reemergence of ZIKV remains a concern. This comprehensive review provides insights into the pathogenesis of ZIKV and highlights the key cellular pathways activated upon ZIKV infection. Additionally, we explore the potential of utilizing microRNAs (miRNAs) and phytocompounds as promising strategies to combat ZIKV infection.

2.
Pest Manag Sci ; 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38153883

RESUMO

BACKGROUND: The common vole has invaded the agroecosystems of northwestern Spain, where outbreaks cause important crop damage and management costs. Little is yet known about the factors causing or modulating vole fluctuations. Here, we used 11 years of vole abundance monitoring data in 40 sites to study density-dependence and weather influence on vole dynamics. Our objective was to identify the population dynamics structure and determine whether there is direct or delayed density-dependence. An evaluation of climatic variables followed, to determine whether they influenced vole population peaks. RESULTS: First- and second-order outbreak dynamics were detected at 7 and 33 study sites, respectively, together with second-order variability in periodicity (2-3 to 4-5-year cycles). Vole population growth was explained by previous year abundance (mainly numbers in summer and spring) at 21 of the sites (52.5%), by weather variables at 11 sites (27.5%; precipitation or temperature in six and five sites, respectively), and by a combination of previous abundance and weather variables in eight sites (20%). CONCLUSIONS: We detected variability in vole spatiotemporal abundance dynamics, which differs in cyclicity and period. We also found regional variation in the relative importance of previous abundances and weather as factors modulating vole fluctuations. Most vole populations were cyclical, with variable periodicity across the region. Our study is a first step towards the development of predictive modeling, by disclosing relevant factors that might trigger vole outbreaks. It improves decision-making processes within integrated management dealing with mitigation of the agricultural impacts caused by voles. © 2023 Society of Chemical Industry.

3.
Pest Manag Sci ; 78(6): 2316-2323, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35243753

RESUMO

BACKGROUND: The common vole (Microtus arvalis) is a very destructive agricultural pest. Particularly in Europe, its monitoring is essential not only for adequate management and outbreak forecasting, but also for accurately determining the vole's impact on affected fields. In this study, several alternatives for estimating the damage to alfalfa fields by voles through unmanned vehicle systems (UASs) and multispectral cameras are presented. Currently, both the farmers and agencies involved in the integrated pest management (IPM) programs of voles do not have sufficiently precise methods for accurate assessments of the real impact to crops. RESULTS: Overall, the four multispectral classification methods presented showed similar performances. However, the normalized difference vegetation index (NDVI)-based segmentation exhibited the most accurate and reliable appraisal of the affected areas. Nevertheless, it must be noted that the simplest method, which was based on an automatic classification, provided results similar to those obtained by more complex methods. In addition, a significant direct relationship was found between the number of active burrows and damage to the alfalfa canopy. CONCLUSION: Unmanned vehicle systems, combined with multispectral imagery classification, are an effective and easily transferable methodology for the assessment and monitoring of common vole damage to agricultural plots. This combination of methods facilitates decision-making processes for IPM control strategies against this pest. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Arvicolinae , Produtos Agrícolas , Agricultura , Animais , Europa (Continente)
4.
J Fungi (Basel) ; 7(6)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073303

RESUMO

Aspergillus sydowii is a moderate halophile fungus extensively studied for its biotechnological potential and halophile responses, which has also been reported as a coral reef pathogen. In a recent publication, the transcriptomic analysis of this fungus, when growing on wheat straw, showed that genes related to cell wall modification and cation transporters were upregulated under hypersaline conditions but not under 0.5 M NaCl, the optimal salinity for growth in this strain. This led us to study osmolyte accumulation as a mechanism to withstand moderate salinity. In this work, we show that A. sydowii accumulates trehalose, arabitol, mannitol, and glycerol with different temporal dynamics, which depend on whether the fungus is exposed to hypo- or hyperosmotic stress. The transcripts coding for enzymes responsible for polyalcohol synthesis were regulated in a stress-dependent manner. Interestingly, A. sydowii contains three homologs (Hog1, Hog2 and MpkC) of the Hog1 MAPK, the master regulator of hyperosmotic stress response in S. cerevisiae and other fungi. We show a differential regulation of these MAPKs under different salinity conditions, including sustained basal Hog1/Hog2 phosphorylation levels in the absence of NaCl or in the presence of 2.0 M NaCl, in contrast to what is observed in S. cerevisiae. These findings indicate that halophilic fungi such as A. sydowii utilize different osmoadaptation mechanisms to hypersaline conditions.

5.
J Fungi (Basel) ; 6(4)2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33260894

RESUMO

Water activity (aw) is critical for microbial growth, as it is severely restricted at aw < 0.90. Saturating NaCl concentrations (~5.0 M) induce extreme water deprivation (aw ≅ 0.75) and cellular stress responses. Halophilic fungi have cellular adaptations that enable osmotic balance and ionic/oxidative stress prevention to grow at high salinity. Here we studied the morphology, osmolyte synthesis, and oxidative stress defenses of the halophile Aspergillus sydowii EXF-12860 at 1.0 M and 5.13 M NaCl. Colony growth, pigmentation, exudate, and spore production were inhibited at NaCl-saturated media. Additionally, hyphae showed unpolarized growth, lower diameter, and increased septation, multicellularity and branching compared to optimal NaCl concentration. Trehalose, mannitol, arabitol, erythritol, and glycerol were produced in the presence of both 1.0 M and 5.13 M NaCl. Exposing A. sydowii cells to 5.13 M NaCl resulted in oxidative stress evidenced by an increase in antioxidant enzymes and lipid peroxidation biomarkers. Also, genes involved in cellular antioxidant defense systems were upregulated. This is the most comprehensive study that investigates the micromorphology and the adaptative cellular response of different non-enzymatic and enzymatic oxidative stress biomarkers in halophilic filamentous fungi.

6.
DNA Cell Biol ; 39(3): 484-497, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31999471

RESUMO

Inflammation plays a key role in carcinogenesis and metastasis. This process involves the inactivation of tumor suppressor molecules, yet the molecular mechanisms by which inflammation impairs tumor suppressors are not completely understood. In this study, we show that proinflammatory signals such as tumor necrosis factor (TNF) support lung cancer metastasis by reducing the levels of the tumor suppressor Merlin through regulation of miR-146a. Immunodeficient mice inoculated with A549 cells expressing high miR-146a levels and low Merlin protein levels exhibited reduced survival, which correlated with the number of metastatic nodes formed. Accordingly, restoring Merlin protein levels inhibited metastasis and increased survival of the mice. Consistent with these results, we found that elevated miR-146a expression levels correlated with low Merlin protein levels in human lung adenocarcinoma. Furthermore, human invasive and metastatic tumors showed higher TNF and miR-146a levels, but lower Merlin protein levels than noninvasive tumors. These findings indicate that upregulation of miR-146a by TNF in lung adenocarcinoma promotes Merlin protein inhibition and metastasis. Thus, we suggest that the ratio between miR-146a and Merlin protein levels could be a relevant molecular biomarker that can predict lung cancer progression and that the TNF/miR-146a/Merlin pathway is a promising new therapeutic target to inhibit lung adenocarcinoma progression.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/metabolismo , MicroRNAs/genética , Neurofibromina 2/genética , Fator de Necrose Tumoral alfa/metabolismo , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Metástase Neoplásica , Neurofibromina 2/metabolismo , Regulação para Cima
7.
Rev Med Chil ; 146(7): 876-884, 2018 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-30534887

RESUMO

BACKGROUND: In 2013 the Chilean regulatory sanitary agency issued a warning concerning dose adjustment and use restriction to avoid severe adverse effects of metoclopramide such tardive dyskinesia. AIM: To study dyskinesia type adverse effects in a population using metoclopramide. MATERIAL AND METHODS: A cross sectional observational study was conducted among patients pertaining to palliative care and diabetes mellitus programs and consuming 10 mg/day or more of metoclopramide. Patients were interrogated looking for extrapiramidal signs and symptoms using a questionnaire validated by two neurologists. RESULTS: In 40% of diabetic patients with gastroparesia and 35% of palliative care patients, extrapyramidal adverse reactions to metoclopramide were suspected. Palliative Care patients suffered the largest number of adverse events. The period of use and individual doses of the drug were largely above Chilean regulatory agency recommendations in all cases. CONCLUSIONS: A significant number of patients using metoclopramide could experience extrapyramidal adverse reactions.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Antagonistas dos Receptores de Dopamina D2/efeitos adversos , Metoclopramida/efeitos adversos , Dor/tratamento farmacológico , Chile , Estudos Transversais , Antagonistas dos Receptores de Dopamina D2/administração & dosagem , Feminino , Humanos , Masculino , Metoclopramida/administração & dosagem , Cuidados Paliativos , Farmacovigilância , Inquéritos e Questionários
8.
Rev. méd. Chile ; 146(7): 876-884, jul. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-961474

RESUMO

Background: In 2013 the Chilean regulatory sanitary agency issued a warning concerning dose adjustment and use restriction to avoid severe adverse effects of metoclopramide such tardive dyskinesia. Aim: To study dyskinesia type adverse effects in a population using metoclopramide. Material and Methods: A cross sectional observational study was conducted among patients pertaining to palliative care and diabetes mellitus programs and consuming 10 mg/day or more of metoclopramide. Patients were interrogated looking for extrapiramidal signs and symptoms using a questionnaire validated by two neurologists. Results: In 40% of diabetic patients with gastroparesia and 35% of palliative care patients, extrapyramidal adverse reactions to metoclopramide were suspected. Palliative Care patients suffered the largest number of adverse events. The period of use and individual doses of the drug were largely above Chilean regulatory agency recommendations in all cases. Conclusions: A significant number of patients using metoclopramide could experience extrapyramidal adverse reactions.


Assuntos
Humanos , Masculino , Feminino , Dor/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Antagonistas dos Receptores de Dopamina D2/efeitos adversos , Metoclopramida/efeitos adversos , Cuidados Paliativos , Chile , Estudos Transversais , Inquéritos e Questionários , Farmacovigilância , Antagonistas dos Receptores de Dopamina D2/administração & dosagem , Metoclopramida/administração & dosagem
9.
J Sci Food Agric ; 97(12): 4066-4074, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28397240

RESUMO

BACKGROUND: The phenolic composition of grapes is key when making decisions about harvest date and ensuring the quality of grapes. The present study aimed to investigate the relationship between the detailed phenolic composition of grapes and the agronomic parameters and hyperspectral indices, with the latter being measured via field radiometry techniques. RESULTS: Good correlations were found between phenolic composition (both anthocyanin and flavanol composition) and some hyperspectral indices related to vigor, such as the NDVI (normalized difference vegetation index) and the SAVI (soil adjusted vegetation index). The strongest correlations were observed between the phenolic composition of grape skin at harvest time and variables measured from grapes at veraison time, as well as variables determined from grapevines at harvest time. The potential usefulness of these hyperspectral indices calculated from measurements performed directly on grapes or grapevines for estimating the anthocyanin and flavanol composition of grape skins was indicated by the high coefficients of determination (R2 = 0.7955 and R2 = 0.8594, respectively) as obtained by means of principal component regression. CONCLUSION: According to the results of the present study, hyperspectral indices calculated from measurements performed directly on grapes at veraison time or on grapevines at harvest time may be useful for estimating the anthocyanin and flavanol composition of grape skins. This suggests that field radiometry might provide valuable information for estimating the phenolic composition of grapes, which may prove to be very useful when establishing strategies for harvest planning. © 2017 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Fenóis/química , Extratos Vegetais/química , Vitis/química , Agricultura , Frutas/química , Frutas/crescimento & desenvolvimento , Solo/química , Vitis/crescimento & desenvolvimento
10.
Biochem Biophys Res Commun ; 468(4): 594-600, 2015 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-26549232

RESUMO

Inactivation of the tumor suppressor Merlin, by deleterious mutations or by protein degradation via sustained growth factor receptor signaling-mediated mechanisms, results in cell transformation and tumor development. In addition to these mechanisms, here we show that, miRNA-dependent negative regulation of Merlin protein levels also promotes cell transformation. We provide experimental evidences showing that miR-146a negatively regulates Merlin protein levels through its interaction with an evolutionary conserved sequence in the 3´ untranslated region of the NF2 mRNA. Merlin downregulation by miR-146a in A549 lung epithelial cells resulted in enhanced cell proliferation, migration and tissue invasion. Accordingly, stable miR-146a-transfectant cells formed tumors with metastatic capacity in vivo. Together our results uncover miRNAs as yet another negative mechanism controlling Merlin tumor suppressor functions.


Assuntos
Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Regulação para Baixo/genética , Humanos , Camundongos , Camundongos Nus , Invasividade Neoplásica/genética , Neoplasias Experimentais/genética , Neurofibromina 2
11.
Cancer Res ; 75(15): 3032-42, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26069249

RESUMO

Immune escape is a hallmark of cancer, but whether it relies upon extrinsic immune-selective pressure or is inherently orchestrated by oncogenic pathways is unresolved. To address this question, we took advantage of an in vitro model of sequentially transformed human mesenchymal stem cells (hMSC). Neoplastic transformation in this model increased the natural immune-evasive properties of hMSC, both by reducing their immunogenicity and by increasing their capacity to inhibit mitogen-driven T-cell proliferation. We also found that IFNγ signaling was globally affected in transformed hMSC. As a consequence, the natural inhibitory effect of hMSC on T-cell proliferation switched from an inducible mechanism depending on IFNγ signaling and mediated by indoleamine 2,3-dioxygenase to a constitutive mechanism that relied upon IL1ß involving both secreted and membrane-expressed molecules. After transformation, increased IL1ß expression both sustained the immunosuppressive properties of hMSC and increased their tumorigenicity. Thus, in this model system, IL1ß acted as intrinsic inflammatory mediator that exerted an autocrine influence on tumor growth by coordinately linking immune escape and tumorigenicity. Collectively, our findings show how oncogenes directly orchestrate inflammation and immune escape to drive the multistep process of cancer progression, independently of any need for immunoediting in the tumor microenvironment.


Assuntos
Inflamação/patologia , Células-Tronco Mesenquimais/imunologia , Células-Tronco Mesenquimais/patologia , Animais , Transformação Celular Neoplásica , Células Cultivadas , Humanos , Evasão da Resposta Imune/fisiologia , Inflamação/imunologia , Interferon gama/metabolismo , Interleucina-1beta/metabolismo , Camundongos Nus , Transdução de Sinais , Linfócitos T/metabolismo , Linfócitos T/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Cell Immunol ; 289(1-2): 174-84, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24841856

RESUMO

Stem cells from mesenchymal origin (MSC) exert a plethora of immunomodulatory effects. We created a neoplastic model based on in vitro step-wise transformation to assess whether oncogenic pathways have the capacity to mould the cross-talk of MSC and lymphocytes. Neoplastic MSC exhibit an increased inhibitory effect on T cell proliferation, either directly or mediated by myeloid derived suppressor cells. Additionally, transformation of MSC enhances T cell apoptosis without reducing either the percentage of CD25 expressing cells or the level of this protein expression. Malignant transformation drives MSC to lose dependency on nitric oxide for immunosuppression whilst increasing the constitutive production of PGE2. Our results indicate that oncogenesis tunes the interplay between MSC and immune cells, favoring cancer immune evasion.


Assuntos
Comunicação Celular/imunologia , Transformação Celular Neoplásica/imunologia , Células-Tronco Mesenquimais/imunologia , Linfócitos T/imunologia , Animais , Apoptose/imunologia , Diferenciação Celular/imunologia , Proliferação de Células , Células Cultivadas , Dinoprostona/biossíntese , Feminino , Terapia de Imunossupressão , Subunidade alfa de Receptor de Interleucina-2/biossíntese , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Óxido Nítrico/imunologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/imunologia , Evasão Tumoral/imunologia , Proteína Supressora de Tumor p53/genética
13.
J Dent Educ ; 75(4): 485-95, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21460269

RESUMO

A revision of the clinical assessment system of the University of Puerto Rico School of Dental Medicine was initiated in 2007, with the goal of achieving a system that would be fully understood and used by both faculty and students to improve student performance throughout the curriculum. The transformation process was organized according to Kotter's Eight-Step Change Model. Some of the initial findings in 2007 were as follows: 87 percent of current daily clinical evaluations were scored at the scale's highest level, 33 percent of faculty members lacked knowledge of the evaluation system, and 60 percent of students reported that faculty members were not well calibrated. As a result of the transformation process, a pilot project has been implemented in the comprehensive clinical course for senior students. The revised assessment methods utilized are verbal daily feedback, clinical evaluations once every three months, a digital portfolio, and competency exams. There is also a productivity component included in the course grade. We conclude that adapting Kotter's model for use in the transformation process has been very useful; gaining support from both the administration and faculty has been essential; and the provision of continuous faculty development activities has been empowering. The American Dental Education Association Commission on Change and Innovation in Dental Education (ADEA CCI) Liaisons at the University of Puerto Rico School of Dental Medicine have been effective in producing a greater awareness among the faculty about the value of the competency-based curriculum and the need for change.


Assuntos
Educação Baseada em Competências , Educação em Odontologia/métodos , Avaliação Educacional , Modelos Educacionais , Currículo , Avaliação Educacional/métodos , Retroalimentação , Objetivos , Humanos , Inovação Organizacional , Porto Rico , Faculdades de Odontologia , Inquéritos e Questionários
14.
Rev. cuba. oftalmol ; 7(1-2): 53-9, ene.-dic. 1994. tab
Artigo em Espanhol | CUMED | ID: cum-5660

RESUMO

En los últimos años los estudios en pacientes con neuropatías han revelado cambios bioquímicos importantes que han explicado la pérdida de la visión por lesiones del nervio óptico con desmielización al nivel de la zona axial del nervio y en la cual los aminoácidos azufrados desempeñan un importante papel metabólico. Este estudio se encaminó a determinar la concentración plasmática de aminoácidos en pacientes con neuropatía epidémica diagnósticados en Cuba. Se encontró que la concentración plasmática de aminoácidos azufrados no cambió respecto al grupo control, por lo que creemos que el factor tóxico tenga un papel primordial. Sin embargo, se encontraron variaciones importantes en un grupo de aminoácidos que pensamos pueda deberse a cambios metabólicos de carácter nutricional que generalmente acompañan a esta enfermedad.


Assuntos
Humanos , Aminoácidos Sulfúricos/análise , Aminoácidos Sulfúricos/metabolismo , Aminoácidos Sulfúricos/sangue , Aminoácidos/análise , Aminoácidos/metabolismo , Aminoácidos/sangue , Distúrbios Nutricionais , Neurite Óptica/epidemiologia , Surtos de Doenças
15.
Rev. cuba. oftalmol ; 7(1/2): 53-9, ene.-dic. 1994. tab
Artigo em Espanhol | LILACS | ID: lil-158511

RESUMO

En los últimos años los estudios en pacientes con neuropatías han reveladocambios bioquímicos importantes que han explicado la pérdida de la visión por lesiones del nervio óptico con desmielización al nivel de la zona axial del nervio y en la cual los aminoácidos azufrados desempeñan un importante papel metabólico. Este estudio se encaminó a determinar la concentración plasmática de aminoácidos en pacientes con neuropatía epidémica diagnósticados en Cuba. Se encontró que la concentración plasmática de aminoácidos azufrados no cambió respecto al grupo control, por lo que creemos que el factor tóxico tenga un papel primordial. Sin embargo, se encontraron variaciones importantes en un grupo de aminoácidos que pensamos pueda deberse a cambios metabólicos de carácter nutricional que generalmente acpmpañan a esta enfermedad


Assuntos
Humanos , Aminoácidos Sulfúricos/análise , Aminoácidos Sulfúricos/metabolismo , Aminoácidos Sulfúricos/sangue , Aminoácidos/análise , Aminoácidos/metabolismo , Aminoácidos/sangue , Surtos de Doenças , Neurite Óptica/epidemiologia , Distúrbios Nutricionais
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