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1.
Braz. j. biol ; 84: e262697, 2024. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1394118

RESUMO

Garlic (Allium sativum) is an important cash food crop, and the biotechnology industry has considerable interest in the plant because of its medicinal importance. These medicinal properties are attributed to organosulphur compounds as the accumulation of these compounds varies according to genotype, locality, light quality, and cultivation practices. In this study, we compared a newly developed garlic variety NARC-G1 by National Agricultural Research Centre (NARC), Islamabad, Pakistan with three different garlic cultivars and highlighted the distinctive attributes like phenotypic characteristics, the content of allicin, elemental profile, and gene polymorphism. Phenotypic analysis showed NARC-G1 has significantly higher bulb weight (66.36g ± 18.58), single clove weight (5.87g ± 1.041), and clove width (17.41mm ± 0.95) which directly correlates to the size of the garlic. The analytical analysis showed the highest allicin content (4.82 ± 0.001) in NARC-G1. Genotyping of the alliinase in all four cultivars showed indels in the gene resulting in distinguishable changes in organosulphur compounds' profile. NARC-G1 is unique from other garlic cultivars and could be the best choice for mass production with proper cultivation and irrigation management. Moreover, for Pakistan NARC-G1 could be a potential contender to earn the industrial benefits with inland cultivation instead of importing garlic alleviating the economic burden.


O alho (Allium sativum) é uma importante cultura alimentar de rendimento e a indústria biotecnológica tem um interesse considerável na planta devido à sua importância medicinal. As propriedades medicinais são atribuídas aos compostos organossulfurados, enquanto o acúmulo de sulfóxidos de cisteína (CSOs) varia de acordo com genótipo, localidade, qualidade da luz e práticas de cultivo. Neste estudo, comparamos uma variedade de alho recém-desenvolvida NARC-G1 pelo Centro Nacional de Pesquisa Agropecuária (NARC), Islamabade, Paquistão, com três diferentes cultivares de alho, e destacamos os atributos distintivos, como características fenotípicas, conteúdo de alicina, perfil elementar e gene polimorfismo. A análise fenotípica mostrou que o NARC-G1 tem peso de bulbo significativamente maior (66.36g ± 18.58), peso de um único dente (5.87g ± 1.041) e largura do dente (17.41mm ± 0.95), o que se correlaciona diretamente com o tamanho do alho. A análise analítica indicou maior teor de alicina (4.82 ± 0.001) no NARC-G1. A genotipagem do gene da aliinase em todas as quatro cultivares mostrou indels no gene, resultando em mudanças distinguíveis no perfil das CSOs. O NARC-G1 é único em relação a outras cultivares de alho e pode ser a melhor escolha para produção em massa com cultivo adequado e manejo de irrigação. Além disso, para o Paquistão, o NARC-G1 pode ser um potencial candidato para obter os benefícios industriais com o cultivo no interior, em vez de importar alho, aliviando o ônus econômico.


Assuntos
Paquistão , Plantas Medicinais , Melhoramento Genético , Alho , Genótipo
2.
Eval Rev ; 47(4): 630-652, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36286594

RESUMO

The COVID-19 outbreak and the global uncertainty it causes produce an apparent panic in stock markets. Efforts to explain the economic spillover effects of COVID-19 can guide authorities to design a control policy against the financial impacts of pandemics. The paper examines the effects of the COVID-19 cases on the stock markets in the emerging Latin American countries of Argentina, Brazil, Chile, Colombia, Mexico, and Peru. The paper employs a continuous partial wavelet methodology to observe lead-lag relations between the daily variables of new COVID-19 cases and the stock market index for each Latin American country. Brazilian new COVID-19 cases led the Bovespa (BVSP) index to decline during the whole period, except February and June 2020, at one month-two month-frequency band. The wavelet and phase difference analyses indicate that, except for Brazil, COVID-19 cases did not affect the stock market indexes adversely during the whole sample period but did affect the stock exchange markets negatively during some sub-sample periods of the entire sample of each country. Dynamics of Latin American stock exchange markets in the short and long run can be explained by some other parameters of real and financial sectors and COVID-19 cases.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , América Latina/epidemiologia , Surtos de Doenças/prevenção & controle , Argentina/epidemiologia , Brasil/epidemiologia
3.
Front Cell Dev Biol ; 10: 811479, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35237599

RESUMO

The G-protein-coupled estrogen receptor (GPER) mediates non-genomic action of estrogen. Due to its differential expression in some tumors as compared to the original healthy tissues, the GPER has been proposed as a therapeutic target. Accordingly, the non-steroidal GPER agonist G-1, which has often demonstrated marked cytotoxicity in experimental models, has been suggested as a novel anticancer agent for several sensitive tumors. We recently revealed that cell lines derived from acute T-cell (query) lymphoblastic leukemia (T-ALL) express the GPER. Here, we address the question whether G-1 is cytotoxic to T-ALL. We have shown that G-1 causes an early rise of intracellular Ca2+, arrests the cell cycle in G2/M, reduces viability, and provokes apoptosis in T-ALL cell lines. Importantly, G-1 caused destabilization and depolymerization of microtubules. We assume that it is a disturbance of the cytoskeleton that causes G-1 cytotoxic and cytostatic effects in our model. The observed cytotoxic effects, apparently, were not triggered by the interaction of G-1 with the GPER as pre-incubation with the highly selective GPER antagonist G-36 was ineffective in preventing the cytotoxicity of G-1. However, G-36 prevented the intracellular Ca2+ rise provoked by G-1. Finally, G-1 showed only a moderate negative effect on the activation of non-leukemic CD4+ lymphocytes. We suggest G-1 as a potential antileukemic drug.

4.
Front Physiol ; 12: 659291, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34393807

RESUMO

BACKGROUND: The protective effect of estrogen on the vasculature cannot be explained only by its action through the receptors ERα and ERß. G protein-coupled estrogen receptors (GPER)-which are widely distributed throughout the cardiovascular system-may also be involved in this response. However, little is known about GPER actions in hypertension. Therefore, in this study we evaluated the vascular response mediated by GPER using a specific agonist, G-1, in spontaneously hypertensive rats (SHR). We hypothesized that G-1 would induce a relaxing response in resistance mesenteric arteries from SHR of both sexes. METHODS: G-1 concentration-response curves (1 nM-10 µM) were performed in mesenteric arteries from SHR of both sexes (10-12-weeks-old, weighing 180-250 g). The effects of G-1 were evaluated before and after endothelial removal and incubation for 30 min with the inhibitors L-NAME (300 µM) and indomethacin (10 µM) alone or combined with clotrimazole (0.75 µM) or catalase (1,000 units/mL). GPER immunolocalization was also investigated, and vascular hydrogen peroxide (H2O2) and ROS were evaluated using dichlorofluorescein (DCF) and dihydroethidium (DHE) staining, respectively. RESULTS: GPER activation promoted a similar relaxing response in resistance mesenteric arteries of female and male hypertensive rats, but with the participation of different endothelial mediators. Males appear to be more dependent on the NO pathway, followed by the H2O2 pathway, and females on the endothelium and H2O2 pathway. CONCLUSION: These findings show that the GPER agonist G-1 can induce a relaxing response in mesenteric arteries from hypertensive rats of both sexes in a similar way, albeit with differential participation of endothelial mediators. These results contribute to the understanding of GPER activation on resistance mesenteric arteries in essential hypertension.

5.
Parasitol Res ; 120(2): 747-750, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33442817

RESUMO

Two domestic cats from the Patagonia rural area in Argentina were found to be naturally infected with Echinococcus granulosus sensu stricto/G1 genotype; so far, the only species/genotype of E. granulosus sensu lato complex described to infect domestic cats. The felines developed abdominal disseminated larval disease; the diagnosis was performed by ultrasound, exploratory laparotomy, and molecular techniques. These results indicate that cystic echinococcosis must be considered for differential diagnosis of felines with abdominal distension and/or observation of vesicles through ultrasound, from endemic areas. Even though cats and dogs are carnivores, differences in digestive physiology and immunological characteristics between them could allow the development of larval or adult worm parasites. Domestic cats with cystic echinococcosis show to be environmentally infected with E. granulosus s. s./G1 eggs.


Assuntos
Doenças do Gato/parasitologia , Equinococose/veterinária , Echinococcus granulosus/isolamento & purificação , Abdome/diagnóstico por imagem , Abdome/parasitologia , Animais , Argentina/epidemiologia , Doenças do Gato/diagnóstico , Gatos , Equinococose/diagnóstico , Equinococose/parasitologia , Echinococcus granulosus/crescimento & desenvolvimento , Genótipo , Larva/crescimento & desenvolvimento , Ultrassonografia
6.
Ann Med Surg (Lond) ; 60: 344-351, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33224488

RESUMO

BACKGROUND: About 15%-25% of appendices removed to treat acute appendicitis present normal macro- and macroscopic morphology. The objective of this study was to verify an association of proinflammatory, neuroendocrine and immune mediators with morphologically normal appendices removed from patients with clinical laboratorial and imaging characteristics of acute appendicitis. MATERIALS AND METHODS: Appendices removed from 121 adult patients of both genders were distributed into three groups according to their following characteristics: group 1: 53 macro- and microscopically normal appendices from patients with clinical, laboratorial and imaging diagnosis of acute appendicitis; group 2: 24 inflamed appendices from patients with clinical, laboratorial, imaging and histopathological diagnosis of acute appendicitis; group 3: 44 normal appendices from patients submitted to right colectomy to treat localized ascending colon adenocarcinoma. All appendices were immunohistochemically studied for gastrin inhibitor peptide, mast cell tryptase, vascular endothelial growth factor; intestinal vasoactive peptide, tumor necrosis factor alpha, interleukin 1, prostaglandin E2, gene-protein product 9.5, CD8 T lymphocytes, synaptophysine, enolase, and S100 protein. RESULTS: The group 1 revealed increased levels of synaptophysine, enolase, mast cell tryptase and PGP-9.5 comparing with the other two groups. The group 2 presented increased levels of interleukin 1, CD8 T lymphocytes and prostaglandin E2 comparing with the other two groups. The group 3 confirmed the normal levels of all these neuroendocrine, immune and proinflammatory mediators. CONCLUSIONS: Morphologically normal appendices removed from patients with clinical and complementary exams indicating acute appendicitis have appendicular neuroimmunoendocrine disorder associated with the mediators synaptophysin, enolase, mast cell-related tryptase and gene-protein product 9.5.

7.
Front Immunol ; 11: 575076, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240264

RESUMO

HLA-G is considered to be an immune checkpoint molecule, a function that is closely linked to the structure and dynamics of the different HLA-G isoforms. Unfortunately, little is known about the structure and dynamics of these isoforms. For instance, there are only seven crystal structures of HLA-G molecules, being all related to a single isoform, and in some cases lacking important residues associated to the interaction with leukocyte receptors. In addition, they lack information on the dynamics of both membrane-bound HLA-G forms, and soluble forms. We took advantage of in silico strategies to disclose the dynamic behavior of selected HLA-G forms, including the membrane-bound HLA-G1 molecule, soluble HLA-G1 dimer, and HLA-G5 isoform. Both the membrane-bound HLA-G1 molecule and the soluble HLA-G1 dimer were quite stable. Residues involved in the interaction with ILT2 and ILT4 receptors (α3 domain) were very close to the lipid bilayer in the complete HLA-G1 molecule, which might limit accessibility. On the other hand, these residues can be completely exposed in the soluble HLA-G1 dimer, due to the free rotation of the disulfide bridge (Cys42/Cys42). In fact, we speculate that this free rotation of each protomer (i.e., the chains composing the dimer) could enable alternative binding modes for ILT2/ILT4 receptors, which in turn could be associated with greater affinity of the soluble HLA-G1 dimer. Structural analysis of the HLA-G5 isoform demonstrated higher stability for the complex containing the peptide and coupled ß2-microglobulin, while structures lacking such domains were significantly unstable. This study reports for the first time structural conformations for the HLA-G5 isoform and the dynamic behavior of HLA-G1 molecules under simulated biological conditions. All modeled structures were made available through GitHub (https://github.com/KavrakiLab/), enabling their use as templates for modeling other alleles and isoforms, as well as for other computational analyses to investigate key molecular interactions.


Assuntos
Membrana Celular/metabolismo , Antígenos HLA-G/metabolismo , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Antígenos HLA-G/química , Antígenos HLA-G/genética , Humanos , Bicamadas Lipídicas , Domínios e Motivos de Interação entre Proteínas , Isoformas de Proteínas , Multimerização Proteica , Estabilidade Proteica , Relação Estrutura-Atividade
8.
Cancers (Basel) ; 12(11)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33218150

RESUMO

Malignant gliomas are the most common malignant and aggressive primary brain tumors in adults, the prognosis being-especially for glioblastomas-extremely poor. There are no effective treatments yet. However, tyrosine kinase receptor (TKR) inhibitors and boron neutron capture therapy (BNCT), together, have been proposed as future therapeutic strategies. In this sense in our ongoing project of developing new anti-glioblastoma drugs, we identified a sunitinib-carborane hybrid agent, 1, with both in vitro selective cytotoxicity and excellent BNCT-behavior. Consequently, we studied the ability of compound 1 to inhibit TKRs, its promotion of cellular death processes, and its effects on the cell cycle. Moreover, we analyzed some relevant drug-like properties of 1, i.e., mutagenicity and ability to cross the blood-brain barrier. These results encouraged us to perform an in vivo anti-glioblastoma proof of concept assay. It turned out to be a selective FLT3, KIT, and PDGFR-ß inhibitor and increased the apoptotic glioma-cell numbers and arrested sub-G1-phase cell cycle. Its in vivo activity in immunosuppressed mice bearing U87 MG human glioblastoma evidenced excellent anti-tumor behavior.

9.
Front Endocrinol (Lausanne) ; 11: 563165, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117280

RESUMO

GPER-1 is a novel membrane sited G protein-coupled estrogen receptor. Clinical studies have shown that patients suffering an estrogen receptor α (ERα)/GPER-1 positive, breast cancer have a lower survival rate than those who have developed ERα-positive/GPER-1 negative tumors. Moreover, absence of GPER-1 improves the prognosis of patients treated with tamoxifen, the most used selective estrogen receptor modulator to treat ERα-positive breast cancer. MCF-7 breast cancer cells were continuously treated with 1,000 nM tamoxifen for 7 days to investigate its effect on GPER-1 protein expression, cell proliferation and intracellular [Ca2+]i mobilization, a key signaling pathway. Breast cancer cells continuously treated with tamoxifen, exhibited a robust [Ca2+]i mobilization after stimulation with 1,000 nM tamoxifen, a response that was blunted by preincubation of cells with G15, a commercial GPER-1 antagonist. Continuously treated cells also displayed a high [Ca2+]i mobilization in response to a commercial GPER-1 agonist (G1) and to estrogen, in a magnitude that doubled the response observed in untreated cells and was almost completely abolished by G15. Proliferation of cells continuously treated with tamoxifen and stimulated with 2,000 nM tamoxifen, was also higher than that observed in untreated cells in a degree that was approximately 90% attributable to GPER-1. Finally, prolonged tamoxifen treatment did not increase ERα expression, but did overexpress the kinin B1 receptor, another GPCR, which we have previously shown is highly expressed in breast tumors and increases proliferation of breast cancer cells. Although we cannot fully extrapolate the results obtained in vitro to the patients, our results shed some light on the occurrence of drug resistance in breast cancer patients who are ERα/GPER-1 positive, have been treated with tamoxifen and display low survival rate. Overexpression of kinin B1 receptor may explain the increased proliferative response observed in breast tumors under continuous treatment with tamoxifen.


Assuntos
Antineoplásicos Hormonais/administração & dosagem , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Receptores de Estrogênio/biossíntese , Receptores Acoplados a Proteínas G/biossíntese , Tamoxifeno/administração & dosagem , Neoplasias da Mama/patologia , Proliferação de Células/fisiologia , Feminino , Humanos , Células MCF-7 , Receptores Acoplados a Proteínas G/agonistas , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia
10.
Molecules ; 25(17)2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32872363

RESUMO

In research on natural molecules with cytotoxic activity that can be used for the development of new anticancer agents, the cytotoxic activity of hexane, chloroform, and methanol extracts from the roots of Acacia schaffneri against colon, lung, and skin cancer cell lines was explored. The hexane extract showed the best activity with an average IC50 of 10.6 µg mL-1. From this extract, three diterpenoids, phyllocladan-16α,19-diol (1), phyllocladan-16α-ol (2), and phylloclad-16-en-3-ol (3), were isolated and characterized by their physical and spectroscopic properties. Diterpenoids 1 and 2 were tested against the same cancer cell lines, as well as their healthy counterparts, CCD841 CoN, MRC5, and VH10, respectively. Compound 1 showed moderate activity (IC50 values between 24 and 70 µg mL-1), although it showed a selective effect against cancer cell lines. Compound 2 was practically inactive. The cytotoxicity mechanism of 1 was analyzed by cell cycle, indicating that the compound induces G0/G1 cell cycle arrest. This effect might be generated by DNA alkylation damage. In addition, compound 1 decreased migration of HT29 cells.


Assuntos
Fabaceae/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fracionamento Químico , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/isolamento & purificação
11.
DNA Repair (Amst) ; 96: 102971, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32987354

RESUMO

How a cell determines a given phenotype upon damaged DNA is an open problem. Cell fate decisions happen at cell cycle checkpoints and it is becoming clearer that the p53 pathway is a major regulator of cell fate decisions involving apoptosis or senescence upon DNA damage, especially at G1/S. However, recent results suggest that this pathway is also involved in autophagy induction upon DNA damage. To our knowledge, in this work we propose the first model of the DNA damage-induced G1/S checkpoint contemplating the decision between three phenotypes: apoptosis, senescence, and autophagy. The Boolean model is proposed based on experiments with U87 glioblastoma cells using the transfection of miR-16 that can induce a DNA damage response. The wild-type case of the model shows that DNA damage induces the checkpoint and the coexistence of the three phenotypes (tristable dynamics), each with a different probability. We also predict that the positive feedback involving ATM, miR-16, and Wip1 has an influence on the tristable state. The model predictions were compared to experiments of gain and loss of function in other three different cell lines (MCF-7, A549, and U2OS) presenting agreement. For p53-deficient cell lines such as HeLa, H1299, and PC-3, our model contemplates the experimental observation that the alternative AMPK pathway can compensate this deficiency. We conclude that at the G1/S checkpoint the p53 pathway (or, in its absence, the AMPK pathway) can regulate the induction of different phenotypes in a stochastic manner in the U87 cell line and others.


Assuntos
Autofagia , Dano ao DNA , Pontos de Checagem da Fase G1 do Ciclo Celular , Modelos Genéticos , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Apoptose , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Senescência Celular , Redes Reguladoras de Genes , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , MicroRNAs/metabolismo , Proteína Fosfatase 2C/metabolismo , Células Tumorais Cultivadas
12.
Toxicol Rep ; 7: 1157-1163, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983903

RESUMO

Aflatoxin M1 is a carcinogenic and genotoxic metabolite of Aflatoxins present in food contaminated by fungi for lactating cattle, it is excreted through milk and when used to make cheese, the toxin will also be transferred to the dairy. The contamination of unripened hard white cheese with AFM1 seems to vary according to the season of the year, possibly due to the change of foodstuff, from fresh pasture in the rainy season to dried foods in the dry season and vice versa. This research determined both the prevalence and contents of AFM1 in cheeses of local and Nicaraguan origin marketed in El Salvador, as well as the changes occurred according to the season and the association between levels of AFM1 with meteorological parameters. The significantly higher prevalence of AFM1 contamination in both local cheeses and Nicaraguans, was found in the dry season and the lowest in the rainy season (41 % vs. 20 %; 31 % vs. 0%, respectively), the same trend was observed in AFM1 contents (0.076 vs. 0.036 µg/kg; 0.050 vs. 0.021 µg/kg, respectively). A significant association was demonstrated between levels of AFM1 with the averages of accumulated rainfall and relative humidity according to the sampled season. The prevalence of AFM1 in cheeses indicate that El Salvador and Nicaragua are endemic to dairy contamination by that mycotoxin. Seasonal variation may be due to a lack of rainfall, that promotes the growth of aflatoxigenic fungi in the crops of raw materials, which will be used for feedstuff intended for dairy cattle, thus, the consumption of contaminated food will cause the temporary increase of AFM1 in milk and their derivatives.

13.
Psicol. ciênc. prof ; 40: e217509, jan.-maio 2020.
Artigo em Português | Index Psicologia - Periódicos, LILACS | ID: biblio-1143555

RESUMO

Resumo A mídia ocupa espaço expressivo na contemporaneidade, produzindo significações sobre fenômenos cotidianos, divulgando-os massivamente e, assim, definindo não só o que existe e o que faz parte da realidade, mas promovendo conotações valorativas sobre os acontecimentos. No contexto brasileiro, a mídia tem sido o principal vetor no que se refere às subjetivações sobre fenômenos da violência e da criminalidade. Tendo como objeto de pesquisa a repercussão no portal de notícias G1 de dois casos cujos protagonistas são jovens envolvidos em atos infracionais, este estudo mapeou as reportagens vinculadas a estes de modo a compreender as subjetividades produzidas, promovendo uma reflexão crítica a respeito da produção do "menor infrator" na mídia e seus desdobramentos. O método empregado para a realização do estudo foi a etnografia on-line, em consonância com os princípios da Teoria Ator-Rede. O rastreamento das matérias promoveu reflexões sobre a produção do "menor infrator", entre elas a percepção de que, tal como as políticas de subjetivação vetorizadas por esses dispositivos, as práticas que criminalizam a juventude pobre ocorrem de modo bastante sutil. É na constante ênfase dada pela mídia a elementos morais específicos e na arbitrariedade com a qual se destaca ou não a presença de transtornos psicológicos que vemos um caso ser tratado como punição merecida e o outro como tragédia. Assim, a veiculação de notícias que envolvem jovens tem se configurado uma importante tática de segregação e exclusão social, promovendo o apoio social às práticas de segurança pública que punem e exterminam jovens pobres.


Abstract The media produce meanings about everyday phenomena, spreading them massively and creating value connotations about events. In Brazil, this has been the main vector when it comes to the subjectivities about the phenomena of violence and criminality. Taking as research object the repercussion of the G1 news portal about two cases where the protagonists are young boys involved in infractions, this study mapped the reports related to them in order to understand the produced subjectivities, promoting a critical reflection on the production of the "juvenile offender" in the media and its consequences. The method used to carry out the study was an on-line ethnography, in accordance with the principles of the Actor-Network Theory. The tracking of the subjects allowed to reflect on the production of the "juvenile offender", being one of them the perception that, just like the policies of subjectivation vectored by these devices, the practices that criminalize the poor and young population happen in a very subtle way. The constant emphasis given by the media to specific moral elements and the arbitrariness with which the presence of psychological disorders is highlighted or not shows one case being treated as a deserved punishment and the other as a tragedy. This is how the news coverage involving young people serves as an important tactic of segregation and social exclusion, promoting social support for public safety and security practices that punish and exterminate poor young people.


Resumen Los medios ocupan un espacio significativo en la contemporaneidad al producir significaciones acerca de los fenómenos cotidianos, divulgarlos masivamente y definir no solo lo que existe y lo que es parte de la realidad, sino también promocionar connotaciones valorativas sobre los acontecimientos. En el contexto brasileño, los medios han sido el principal vector en lo que se refiere a las subjetivaciones sobre los fenómenos de la violencia y de la criminalidad. Teniendo como el objeto de la investigación la repercusión en el portal de noticias G1 de dos casos que tienen como protagonistas jóvenes que se involucraron en actos delictivos, la investigación ha mapeado los reportajes vinculados para comprender las subjetividades producidas al hacer una reflexión crítica a respeto de la producción acerca del "menor infractor" en los medios y sus implicaciones. Se utilizó la etnografía en línea según los principios de la teoría actor-red como método de investigación. El rastreo de los reportajes permitió reflexionar sobre la producción acerca del "menor infractor", entre ellas la percepción de que, tal como las políticas de subjetivación vectorizadas por estas plataformas, las prácticas que criminalizan la juventud pobre ocurren de modo bastante sutil. Sin embargo, es en el constante énfasis dado por los medios a elementos morales específicos y en la arbitrariedad con la cual se destaca o no la presencia de trastornos psicológicos que vemos un caso ser tratado con la debida punición y el otro, como una tragedia. La difusión de noticias que involucran a los jóvenes se traduce en una importante táctica de segregación y exclusión social, fomentando el apoyo social a prácticas de seguridad pública que castigan y exterminan a los jóvenes pobres.


Assuntos
Humanos , Adolescente , Violência , Crime , Menores de Idade , Mídia Audiovisual , Meios de Comunicação de Massa , Antropologia Cultural , Percepção , População , Pobreza , Punição , Segurança , Apoio Social , Programas de Rastreamento , Criminosos , Mídias Sociais , Marginalização Social
14.
FEBS Lett ; 594(2): 227-239, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31545515

RESUMO

MicroRNA-34a-5p regulates the G1/S checkpoint in non-small cell lung cancer (NSCLC) cells. Forced expression of miR-34a-5p enhances p21 expression and promotes cellular senescence, whereas knockout of miR-34a-5p decreases senescence and increases apoptosis. This suggests that p21 is the main effector of a senescence-apoptosis switch in NSCLC cells; however, the molecular mechanisms controlling this switch are unclear. In this work, we propose a Boolean model of G1/S checkpoint regulation, contemplating the regulatory influences of p21 by miR-34a-5p. The predicted probabilities of our model are in excellent agreement with experimental data. Our model supports that p21 is the main effector of a senescence/apoptosis switch and that the disruption of the positive feedback involving ATM, miR-34a-5p, and the histone deacetylase HDAC1 abrogates senescence.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , MicroRNAs/genética , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Senescência Celular/genética , Regulação Neoplásica da Expressão Gênica/genética , Histona Desacetilase 1/genética , Humanos
15.
Br J Nutr ; 121(12): 1365-1375, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30887937

RESUMO

Diabetes mellitus is a global epidemic, characterised as a heterogeneous group of metabolic disorders associated with high risk of CVD. Green banana biomass, which is composed of resistant starches (RS) and cannot be hydrolysed by amylases, delays gastric emptying and modulates insulin sensitivity, thus contributing to improve metabolic disorders. The aim of the present study was to investigate the effects of consumption of RS from green banana biomass on body composition, fasting plasma glucose, glycated Hb (HbA1c) and homeostasis model assessment of insulin resistance in subjects with pre-diabetes or type 2 diabetes on top of treatment. Middle-aged subjects (n 113) of both sexes with pre-diabetes (HbA1c: 5·7-6·4 %) or diabetes (HbA1c ≥ 6·5 %) were randomised to receive nutritional support plus green banana biomass (40 g) (RS: approximately 4·5 g, G1, n 62) or diet alone (G2, n 51) for 24 weeks. Body composition, biochemical analyses and dietary intake were evaluated at the beginning and end of the study. In the experimental group (G1), consumption of RS was associated with reduction in HbA1c (P = 0·0001), fasting glucose (P = 0·021), diastolic blood pressure (P = 0·010), body weight (P = 0·002), BMI (P = 0·006), waist and hip circumferences (P < 0·01), fat mass percentage (P = 0·001) and increase in lean mass percentage (P = 0·011). In controls (G2), reductions were observed in waist and hip circumferences (P < 0·01), HbA1c (P = 0·002) and high-density lipoprotein-cholesterol (P = 0·020). In pre-diabetes or diabetes, non-significant differences were observed in the percentage reduction in HbA1c and fasting glucose in exploratory analyses. Our results indicate that the consumption of bioactive starches is a good dietary strategy to improve metabolic control and body composition.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Dieta/métodos , Musa , Estado Pré-Diabético/sangue , Amido/administração & dosagem , Biomassa , Glicemia/metabolismo , Composição Corporal/efeitos dos fármacos , Jejum/sangue , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Insulina/sangue , Resistência à Insulina , Masculino , Pessoa de Meia-Idade
16.
J Wildl Dis ; 55(3): 694-698, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30789781

RESUMO

Cystic echinococcosis (CE) is a zoonotic parasitic disease associated with Echinococcus granulosus. The parasite is maintained by domestic and wild canids as definitive hosts with several ungulate species as intermediate hosts in domestic and peridomestic transmission cycles. In Chile, CE is endemic, and the role of livestock and dogs (Canis lupus familiaris) in the cycle and the accidental infection of humans are widely documented at rural sites. However, the role of wild herbivores in wild cycles or the potential transmission of CE from livestock is still unknown in Chile and the rest of South America. We used molecular techniques to describe CE infecting a Patagonian huemul (Hippocamelus bisulcus) in Cerro Castillo National Reserve (Aysén region, Chile). We make inferences about the risk of disease spillover from sympatric domestic and wild species. The DNA-based molecular analysis revealed that the huemul was infected with E. granulosus G1 genotype, sharing haplotypes with other G1 samples collected from sheep (Ovis aries) and cattle (Bos taurus) worldwide. Geographic overlap between sheep and huemul populations in the reserve likely facilitates parasite spillover into wild deer populations, with shepherd or stray dogs and wild foxes (Lycalopex culpaeus) potentially acting as bridging hosts between livestock and the endangered huemul. Further studies are warranted to understand the implications of E. granulosus for huemul conservation throughout the Chilean Patagonia.


Assuntos
Cervos/parasitologia , Equinococose/veterinária , Echinococcus granulosus , Espécies em Perigo de Extinção , Animais , Chile/epidemiologia , Equinococose/epidemiologia , Equinococose/parasitologia , Echinococcus granulosus/genética , Echinococcus granulosus/isolamento & purificação , Feminino , Genótipo
17.
Infect Genet Evol ; 69: 255-266, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30763774

RESUMO

Worldwide rotaviruses A (RVA) are responsible for approximately 215,000 deaths annually among children aged <5 years. RVA G1P[8] remains associated with >50% of gastroenteritis cases in this age group. The aim of this study was to assess the genetic variability of G1P[8] strains detected in children with severe diarrhea in Belém, Pará, Brazil, during the post-rotavirus vaccine introduction era. Phylogenetic analysis clustered the VP4 and VP7 genes of 40 samples selected between 2009 and 2011 into lineages found to be different from the Rotarix® vaccine strain. A detailed investigation of their complete genotype constellations identified 2 reassortant viruses (5%), resulting from reassortments between the genogroups Wa-like and DS-1-like (G1-P[8]-I1-R2-C1-M1-A1-N1-T2-E1-H1) and Wa-like and AU-1-like (G1-P[8]-I1-R3-C1-M1-A1-N1-T1-E1-H1) genotype constellations. A comparison of the amino acid residues presents in the antigenic epitopes of VP7 and VP4, showed differences in the electrostatic charges distribution, between wild type Brazilian strains and the Rotarix® and RotaTeq® vaccine strains. These findings reflect the structural analyses of the antigenic regions of VP7 and VP4 of the RVA G1P[8] in children with gastroenteritis in Northern Brazil raising the hypothesis that structural modifications at these sites over time may account for the emergence of new strains that could possibly pose a challenge to current vaccines.


Assuntos
Diarreia/epidemiologia , Diarreia/virologia , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/genética , Antígenos Virais/química , Antígenos Virais/genética , Antígenos Virais/imunologia , Brasil/epidemiologia , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Diarreia/prevenção & controle , Variação Genética , Genoma Viral , Humanos , Filogenia , Vírus Reordenados/genética , Vírus Reordenados/imunologia , Rotavirus/imunologia , Infecções por Rotavirus/prevenção & controle , Análise de Sequência de DNA
18.
Exp Mol Pathol ; 107: 95-101, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30610843

RESUMO

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Given the comments of Dr Elisabeth Bik regarding this article "... the Western blot bands in all 400+ papers are all very regularly spaced and have a smooth appearance in the shape of a dumbbell or tadpole, without any of the usual smudges or stains. All bands are placed on similar looking backgrounds, suggesting they were copy/pasted from other sources, or computer generated", the journal requested the authors to provide the raw data. However, the authors were not able to fulfil this request and therefore the Editor-in-Chief decided to retract the article.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzopiranos/farmacologia , Indenos/farmacologia , MicroRNAs/biossíntese , Neuroma Acústico/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , MicroRNAs/efeitos dos fármacos , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Regulação para Cima
19.
Toxicol Rep ; 5: 671-678, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30009135

RESUMO

Aflatoxin M1 (AFM1) is a metabolite of Aflatoxin B1 (AFB1) and is excreted through cow´s milk. AFM1 contamination of milk is extended geographically and there might be seasons-related variations for both prevalence and contents, with higher than average values in regions with long periods of drought like El Salvador. Therefore, this project quantified AFM1 levels in raw cow milk and AFs in cattle feedstuffs, during the transitional dry-rainy seasons of two consecutive years and it determined the variation of occurrence and contents associated to drought. Significant variations were shown from year to year in the prevalence of contamination (30% vs. 20%) and in the average levels of AFM1 in milk (0.056 vs 0.039 µg/kg), associated with drought and increased temperature. The AFs median levels raised significantly with the drought period (from 22.5 to 10.3 µg/kg). A significant relationship was demonstrated between AFs levels and those of AFM1, both in the year with drought and without that condition. AFM1 positive cases and its levels in milk increase in drought and hot conditions, AFs levels in the cattle feed tend to be higher with the same, as well. Both relationship between AFs and AFM1 levels and their association with drought were demonstrated. So that, heat and drought stress conditions can evoke raising effects on both Aflatoxins level and occurrence due to AFM1 in milk is a carryover from AFs contaminated feedstuffs ingested by dairy cows.

20.
Food Chem ; 241: 113-121, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28958507

RESUMO

Aspergillus flavus is a filamentous fungus found in nature and characterized by the production of bright and colourful colonies. It grows on different substrates, producing secondary metabolites and, if present in foodstuffs, can be a source of health problems for humans and animals, as well as causing economic losses. Traditional methods for fungal identification are based on morphological characteristics, requiring specialists and being very time-consuming. The development of analytical alternatives might have advantages such as greater efficiency, more reproducibility and be less time-consuming. Thus, a qualitative analytical method to detect Aspergillus flavus in food samples, based on the identification of fungal chemical markers by HPLC-MS, was developed. The method comprises methanol extraction followed by HPLC-MS analysis, and was able to identify 14 fungus secondary metabolites, namely aflatoxin B1, aflatoxin G1, aspergillic acid, aspyrone, betaine, chrysogine, deacetyl parasiticolide A, flufuran, gregatin B, hydroxysydonic acid, nicotinic acid, phomaligin A, spinulosin and terrein.


Assuntos
Aspergillus flavus , Aflatoxina B1 , Aflatoxinas , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Reprodutibilidade dos Testes
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