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1.
Microbiol Spectr ; 12(4): e0274123, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38364080

RESUMO

Human populations can be affected in unpredictable ways by the emergence and spread of zoonotic diseases. The COVID-19 (coronavirus disease of 2019) pandemic was a reminder of how devastating these events can be if left unchecked. However, once they have spread globally, the impact of these diseases when entering non-exposed wildlife populations is unknown. The current study reports the infection of brown-headed spider monkeys (Ateles fusciceps) at a wildlife rescue center in Ecuador. Four monkeys were hospitalized, and all tested positive for SARS-CoV-2 (Severe acute respiratory syndrome coronavirus 2) by RT-qPCR (Quantitative Reverse Transcription PCR). Fecal samples (n = 12) from monkeys at the rescue center also tested positive; three zookeepers responsible for feeding and deworming the monkeys also tested positive, suggesting human-animal transmission. Whole genome sequencing identified most samples' omicron clade 22B BA.5 lineage. These findings highlight the threat posed by an emerging zoonotic disease in wildlife species and the importance of preventing spillover and spillback events during epidemic or pandemic events.IMPORTANCEAlthough COVID-19 (coronavirus disease of 2019) has been primarily contained in humans through widespread vaccination, the impact and incidence of SARS-CoV-2 (Severe acute respiratory syndrome coronavirus) and its transmission and epidemiology in wildlife may need to be addressed. In some natural environments, the proximity of animals to humans is difficult to control, creating perfect scenarios where susceptible wildlife can acquire the virus from humans. In these places, it is essential to understand how transmission can occur and to develop protocols to prevent infection. This study reports the infection of brown-headed spider monkeys with SARS-CoV-2, a red-listed monkey species, at a wildlife recovery center in Ecuador. This study reports the infection of brown-headed spider monkeys with SARS-CoV-2, indicating the potential for transmission between humans and wildlife primates and the importance of preventing such events in the future.


Assuntos
Atelinae , COVID-19 , Animais , Humanos , Animais Selvagens , COVID-19/epidemiologia , COVID-19/veterinária , Equador/epidemiologia , SARS-CoV-2/genética , Zoonoses/epidemiologia , América do Sul , Pandemias
2.
G3 (Bethesda) ; 14(3)2024 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-38244218

RESUMO

The Ecuadorian brown-headed spider monkey (Ateles fusciceps fusciceps) is currently considered one of the most endangered primates in the world and is classified as critically endangered [International union for conservation of nature (IUCN)]. It faces multiple threats, the most significant one being habitat loss due to deforestation in western Ecuador. Genomic tools are keys for the management of endangered species, but this requires a reference genome, which until now was unavailable for A. f. fusciceps. The present study reports the first whole-genome sequence and assembly of A. f. fusciceps generated using Oxford Nanopore long reads. DNA was extracted from a subadult male, and libraries were prepared for sequencing following the Ligation Sequencing Kit SQK-LSK112 workflow. Sequencing was performed using a MinION Mk1C sequencer. The sequencing reads were processed to generate a genome assembly. Two different assemblers were used to obtain draft genomes using raw reads, of which the Flye assembly was found to be superior. The final assembly has a total length of 2.63 Gb and contains 3,861 contigs, with an N50 of 7,560,531 bp. The assembly was analyzed for annotation completeness based on primate ortholog prediction using a high-resolution database, and was found to be 84.3% complete, with a low number of duplicated genes indicating a precise assembly. The annotation of the assembly predicted 31,417 protein-coding genes, comparable with other mammal assemblies. A reference genome for this critically endangered species will allow researchers to gain insight into the genetics of its populations and thus aid conservation and management efforts of this vulnerable species.


Assuntos
Atelinae , Nanoporos , Masculino , Animais , Equador , Espécies em Perigo de Extinção , Análise de Sequência de DNA , Sequenciamento de Nucleotídeos em Larga Escala , Mamíferos
4.
J Endovasc Ther ; : 15266028221148381, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36609171

RESUMO

PURPOSE: Thoracic endovascular aortic repair (TEVAR) has been described to be superior to an open surgical approach, and previous studies have found superiority in TEVAR by reducing overall morbidity and mortality rates. This study aimed to describe the outcomes of TEVAR for patients with thoracic aortic disease at a high complexity. MATERIALS AND METHODS: Descriptive study, developed by a retrospective review of a prospectively collected database. Patients aged above 18 years who underwent TEVAR between 2012 and 2022 were included. Patient demographics, perioperative data, surgical outcomes, morbidity, and mortality were described. Statistical and multivariate analyses were made. Statistical significance was reached when p values were <0.05. RESULTS: A total of 66 patients were included. Male patients were 60.61% and the mean age was 69.24 years. Associated aortic diseases were aneurysms (68.18%), ulcer-related (4.55%), intramural-related hematoma (7.58%), trauma-related pathology (1.52%), and aortic dissection (30.30%). The mean hospital stay was 18.10 days, and intensive care unit was required for 98.48%. At 30 days, the mortality rate was 10.61% and the reintervention rate was 21.21%. Increased intraoperative blood loss (p=0.001) and male sex (p=0.04) showed statistical relationship with mortality. Underweight patients have 6.7 and 11.4 times more risk of complications and endoleak compared with higher body mass index values (p=0.04, 95% confidence interval [CI]=0.82-7.21) and (p=0.02, 95% CI=1.31-12.57), respectively. CONCLUSION: Thoracic endovascular aortic repair seems to be a feasible option for patients with thoracic aortic pathologies, with adequate rates of mortality and morbidity. Underweight patients seem to have an increased risk of overall morbidity and increased risk for endoleak. Further prospective studies are needed to prove our results. CLINICAL IMPACT: Obesity and BMI are widely studied in the surgical literature. According to our study, there is a paradox regarding the outcomes of patients treated with TEVAR in terms of postoperative complications and mortality related to the body mass index. And shouldn't be considered as a high-risk feature in terms of postoperative morbidity and mortality in this procedure.

5.
Front Microbiol ; 13: 826571, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35317261

RESUMO

The crop Vitis vinifera (L.) is of great economic importance as Chile is one of the main wine-producing countries, reaching a vineyard area of 145,000 ha. This vine crop is usually very sensitive to local condition changes and agronomic practices; therefore, strategies to counteract the expected future decrease in water level for agricultural irrigation, temperature increase, extreme water stress (abiotic stress), as well as increase in pathogenic diseases (biotic stress) related to climate change will be of vital importance for this crop. Studies carried out in recent years have suggested that arbuscular mycorrhizal fungi (AMF) can provide key ecosystem services to host plants, such as water uptake implementation and enhanced absorption of nutrients such as P and N, which are key factors for improving the nutritional status of the vine. AMF use in viticulture will contribute also to sustainable agronomic management and bioprotection against pathogens. Here we will present (1) the current status of grapevines in Chile, (2) the main problems in grapevines related to water stress and associated with climate change, (3) the importance of AMF to face water stress and pathogens, and (4) the application of AMF as a biotechnological and sustainable tool in vineyards.

6.
Biomed Pharmacother ; 141: 111947, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34328122

RESUMO

Cardiac fibroblasts (CF) play an important role in the healing process and in pathological remodeling of cardiac tissue. As sentinel cells in the heart, they respond to inflammatory stimuli, expressing cytokines and cell adhesion proteins, which ultimately lead to increased recruitment of monocytes and enhancement of the inflammatory response. Angiotensin II (Ang II) triggers an inflammatory response, leading to cardiac tissue remodeling. On the other hand, RvD1 has been shown to contribute to the resolution of inflammation; however, its role in Ang II-treated CF has not been addressed until now. The present research aimed to study the effect of RvD1 on cytokine levels, cell adhesion proteins expression in a model of Ang II-triggered inflammatory response. CF from adult Sprague Dawley rats were used to study mRNA and protein levels of MCP-1, IL-6, TNF-a, IL-10, ICAM-1 and VCAM-1; and adhesion of spleen mononuclear cells to CF after Ang II stimulation. Our results show that Ang II increased IL-6, MCP-1 and TNF-a mRNA levels, but only increased IL-6 and MCP-1 protein levels. These effects were blocked by Losartan, but not by PD123369. Moreover, RvD1 was able to prevent all Ang II effects in CF. Additionally, RvD1 reduced the intracellular Ca2+ increase triggered by Ang II, indicating that RvD1 acts in an early manner to block Ang II signaling. Conclusion: our findings confirm the pro-resolutive effects of inflammation by RvD1, which at the cardiovascular level, could contribute to repair damaged cardiac tissue.


Assuntos
Angiotensina II/toxicidade , Adesão Celular/efeitos dos fármacos , Citocinas/antagonistas & inibidores , Ácidos Docosa-Hexaenoicos/farmacologia , Monócitos/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Animais , Adesão Celular/fisiologia , Células Cultivadas , Citocinas/biossíntese , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Expressão Gênica , Masculino , Monócitos/metabolismo , Miócitos Cardíacos/metabolismo , Ratos , Ratos Sprague-Dawley
7.
Edumecentro ; 12(1): 30-45, ene.-mar. 2020. tab
Artigo em Espanhol | LILACS | ID: biblio-1089997

RESUMO

RESUMEN Fundamento: en la electrocardiografía es importante tener la habilidad de interpretar, además de confianza para lograr una definición certera en el diagnóstico y tratamiento. Objetivo: implementar un taller utilizando el aprendizaje basado en la simulación clínica para la interpretación del electrocardiograma. Métodos: se realizó un estudio de tipo descriptivo y longitudinal en la Facultad de Medicina de la Universidad Nacional Autónoma de México, durante 2018. Se utilizaron métodos teóricos: análisis-síntesis e inducción-deducción; y empíricos: una encuesta y un examen de interpretación de electrocardiograma antes y después del taller aplicado. Resultados: en la evaluación sobre la identificación del electrocardiograma hubo una mejoría significativa posterior a la realización del taller en aspectos como: la interpretación del ritmo, del eje cardíaco, de ondas y en la asignación de diagnósticos en un menor tiempo según el postest. Se constató la diferencia de resultados tanto en confianza, aptitudes obtenidas, resolución de dudas y de aprendizaje reflexivo centrados en la génesis de cada aspecto del electrocardiograma, lo que permitió al equipo de trabajo ubicarlos como puntos clave en la adquisición de habilidades prácticas e intelectuales. Conclusiones: la implementación del taller permitió una mejoría significativa en las habilidades de los estudiantes para la interpretación del electrocardiograma, lo cual condicionó que se sintieran más confiados en sus apreciaciones; por lo que se evidenció la efectividad de su aplicación.


ABSTRACT Background: in electrocardiography it is important to have the ability to interpret, as well as confidence to achieve an accurate definition in diagnosis and treatment. Objective: to implement a workshop using clinical simulation based learning for electrocardiogram interpretation. Methods: a descriptive and longitudinal study was carried out at the Faculty of Medicine of Mexico National Autonomous University, during 2018. Theoretical methods were used: analysis-synthesis and induction-deduction; and empirical: a survey and an electrocardiogram interpretation test before and after the applied workshop. Results: in the evaluation on the identification of the electrocardiogram there was a meaningful improvement after the workshop was carried out in aspects such as: the interpretation of the rhythm, of the cardiac axis, of waves and in the assignment of diagnoses in a shorter time according to the posttest. The difference in results was observed both in confidence, skills obtained, resolution of doubts and reflexive learning focused on the genesis of each aspect of the electrocardiogram, which allowed the working team to locate them as key points in the acquisition of practical and intellectual skills. Conclusions: the implementation of the workshop allowed a meaningful improvement in the students' abilities to interpret the electrocardiogram, which caused them to feel more confident in their assessments; so the effectiveness of its application was evidenced.


Assuntos
Eletrocardiografia , Estudantes de Medicina , Educação Médica , Aprendizagem
8.
Antioxidants (Basel) ; 8(12)2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31817022

RESUMO

Acute myocardial infarction is one of the leading causes of death worldwide and thus, an extensively studied disease. Nonetheless, the effects of ischemia/reperfusion injury elicited by oxidative stress on cardiac fibroblast function associated with tissue repair are not completely understood. Ascorbic acid, deferoxamine, and N-acetylcysteine (A/D/N) are antioxidants with known cardioprotective effects, but the potential beneficial effects of combining these antioxidants in the tissue repair properties of cardiac fibroblasts remain unknown. Thus, the aim of this study was to evaluate whether the pharmacological association of these antioxidants, at low concentrations, could confer protection to cardiac fibroblasts against simulated ischemia/reperfusion injury. To test this, neonatal rat cardiac fibroblasts were subjected to simulated ischemia/reperfusion in the presence or absence of A/D/N treatment added at the beginning of simulated reperfusion. Cell viability was assessed using trypan blue staining, and intracellular reactive oxygen species (ROS) production was assessed using a 2',7'-dichlorofluorescin diacetate probe. Cell death was measured by flow cytometry using propidium iodide. Cell signaling mechanisms, differentiation into myofibroblasts and pro-collagen I production were determined by Western blot, whereas migration was evaluated using the wound healing assay. Our results show that A/D/N association using a low concentration of each antioxidant increased cardiac fibroblast viability, but that their separate administration did not provide protection. In addition, A/D/N association attenuated oxidative stress triggered by simulated ischemia/reperfusion, induced phosphorylation of pro-survival extracellular-signal-regulated kinases 1/2 (ERK1/2) and PKB (protein kinase B)/Akt, and decreased phosphorylation of the pro-apoptotic proteins p38- mitogen-activated protein kinase (p38-MAPK) and c-Jun-N-terminal kinase (JNK). Moreover, treatment with A/D/N also reduced reperfusion-induced apoptosis, evidenced by a decrease in the sub-G1 population, lower fragmentation of pro-caspases 9 and 3, as well as increased B-cell lymphomaextra large protein (Bcl-xL)/Bcl-2-associated X protein (Bax) ratio. Furthermore, simulated ischemia/reperfusion abolished serum-induced migration, TGF-ß1 (transforming growth factor beta 1)-mediated cardiac fibroblast-to-cardiac myofibroblast differentiation, and angiotensin II-induced pro-collagen I synthesis, but these effects were prevented by treatment with A/D/N. In conclusion, this is the first study where a pharmacological combination of A/D/N, at low concentrations, protected cardiac fibroblast viability and function after simulated ischemia/reperfusion, and thereby represents a novel therapeutic approach for cardioprotection.

9.
Rev. adm. pública (Online) ; 53(4): 657-686, jul.-ago. 2019. tab, graf
Artigo em Português | LILACS | ID: biblio-1041650

RESUMO

Resumo Esta pesquisa objetivou identificar aspectos interferentes na implementação da gestão estratégica de pessoas (GEP) nos órgãos do Poder Legislativo Federal brasileiro e as possíveis relações entre eles. Por meio de entrevistas e grupos focais realizados com 16 gestores do Senado Federal (SF) e da Câmara dos Deputados (CD) foram identificados 21 aspectos interferentes, divididos em categorias institucionais, políticas, organizacionais e setoriais, bem como foram elaborados modelos teórico-empíricos das influências exercidas por cada um dos aspectos sobre os demais, a partir do que se concluiu que os condicionantes mais significativos teriam natureza política, pois definiriam os recursos e a autonomia disponíveis para as unidades de gestão de pessoas (GP) conduzirem o processo de implementação.


Resumen Esta investigación se propuso identificar aspectos interferentes en la implementación de la gestión estratégica de personas en los órganos del Legislativo Federal brasileño y las posibles relaciones entre ellos. Por medio de entrevistas y grupos focales realizados con 16 gestores del Senado Federal y de la Cámara de Diputados, se identificaron 21 aspectos interferentes, divididos en categorías institucionales, políticas, organizativas y sectoriales, así como se elaboraron modelos teórico-empíricos de las influencias ejercidas por cada uno de los aspectos sobre los demás, a partir de lo que se concluyó que los condicionantes más significativos tendrían naturaleza política, pues definirían los recursos y la autonomía disponibles para que las unidades de gestión de personas conduzcan el proceso de implementación.


Abstract This research aimed to identify interfering aspects in the implementation of strategic human resource management in Brazilian Federal Legislative bodies, as well as the possible relations between them. Through interviews and focus groups with 16 managers of the Federal Senate and the Chamber of Deputies, 21 interfering aspects were identified, divided into institutional, political, organizational, and sectoral categories. The study elaborated theoretical-empirical models of the influences exerted by each of the aspects on the others, which supported the conclusion that the most significant constraints are of political nature, since they would define the resources and the autonomy available to human resource management units to lead the implementation process.


Assuntos
Organização e Administração , Administração Pública , Poder Legislativo , Pessoas
10.
Bol. Hosp. Viña del Mar ; 75(4): 76-79, 2019.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1398170

RESUMO

Objetivos: Comparar los niveles plasmáticos de Vitamina D (VD) en adultos en dos períodos estacionales y evaluar algunos factores que afectan a estos niveles. Pacientes y métodos: Estudio de corte transversal en el que se estudiaron adultos en dos períodos de tiempo, agosto a octubre de 2018 (grupo 1) y febrero a abril de 2019 (grupo 2). Se midieron niveles plasmáticos de VD a ambos grupos. Se obtuvieron datos demográficos y clínicos, incluyendo el uso de suplementos de VD, a través de un cuestionario autoaplicado validado. Se clasificó el nivel de VD en deficiente (< 20 ng/dl), insuficiente (21-30 ng/dl), y suficiente (> 30 ng/dl). Se consideró adulto mayor (AM) a sujetos de ≥ 65 años. Resultados: 207 pacientes (104 en el grupo 1 y 103 en grupo 2), 165 fueron mujeres. Un 31,9% (n=66) tenía niveles deficientes de VD y un 42,5% (n=88) utilizaba algún tipo de suplemento de VD. Los niveles de VD fueron mayores en el grupo 2 (media 31,2 ng/dl) respecto al grupo 1 (media 24,1 ng/dl; p<0,0001), pero esta diferencia solo fue significativa en quienes tomaban suplementos de VD. Por otro lado, el uso de suplemento de VD se asoció a niveles más altos de VD (media 33,1 ng/ml; p<0.001). Además, hubo mayores niveles en pacientes mayores de 65 años (p<0,01). No hubo diferencias estadísticamente significativas en niveles de VD según sexo ni estado nutricional. Conclusión: Se observaron mayores niveles de VD en usuarios de suplementos de esta vitamina, sin diferencias según período estacional.


Objectives:To compare plasmatic levels of vitamin D in adults in two seasonal periods and evaluate some factors affecting these levels. Patients and methods: Transversal cohort study in which adults were studied in two time periods, August to October 2018 (group 1) and February to April 2019 (group 2). Plasmatic levels of vitamin D were measured in both groups. Demographic and clinical details, including the use of vitamin D supplements, were obtained through a self-administered questionnaire. Results were classified as deficient (<20ng/dL), insufficient (21 ­ 30 ng/dL) and normal (>30 ng/dL). The elderly were defined to be the ≥65´s. Results: 207 patients (104 in group 1 and 103 in group 2), 165 were female. 31.9% (n=66) had deficient levels of vitamin D and 42,5% (n=88) used a vitamin D supplement. Vitamin D levels were higher in group 2 (median 31.2 ng/dL) compared with group 1 (median 24.1 ng/dL; p<0.0001), but this difference was significant only in those taking vitamin D supplements. On the other hand, use of vitamin D supplements was associated with higher vitamin D levels (median 33.1 ng/dL; p<0.001). Moreover, levels were higher in the over 65s (p<0.01). There were no statistically significant differences in vitamin D levels found between sexes or different nutritional states. Conclusion: Higher vitamin D levels were observed in persons taking vitamin D supplements. There were no seasonal differences.

11.
Food Chem ; 154: 117-26, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24518323

RESUMO

MPs (3-alkyl-2-methoxypyrazines) are grape-derived aroma compounds that are associated with detrimental herbaceous flavours in some wines. It is well known that several viticultural and environmental parameters can modulate MP concentrations in grapes, although comprehensive molecular studies have not been conducted in this field. Although the biosynthesis pathway of MPs has not been fully elucidated, four Vitis vinifera O-methyltransferase genes (VvOMT1-4) have been related to be involved in MP biosynthesis. We assessed whether different abiotic stresses induction have an impact on MP levels in grapes and wines from seeded and parthenocarpic fruits. Our results show that the timing of VvOMT3 expression is associated with the period of MPs accumulation in seeded fruits during both abiotic stresses, whereas no association was found in parthenocarpic fruits. These results are discussed in the context of how different viticultural practices can modulate VvOMT gene expression, which has a direct impact on MPs levels in wines.


Assuntos
Metiltransferases/genética , Proteínas de Plantas/genética , Pirazinas/metabolismo , Sementes/metabolismo , Vitis/enzimologia , Vias Biossintéticas , Aromatizantes/metabolismo , Frutas/química , Frutas/enzimologia , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Metiltransferases/metabolismo , Proteínas de Plantas/metabolismo , Sementes/química , Sementes/enzimologia , Sementes/genética , Vitis/química , Vitis/genética , Vitis/metabolismo , Vinho/análise
12.
Nucleic Acids Res ; 41(11): 5827-36, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23609537

RESUMO

5-Aza-2'-deoxycytidine (5-azadC) is a DNA methyltransferase (DNMT) inhibitor increasingly used in treatments of hematological diseases and works by being incorporated into DNA and trapping DNMT. It is unclear what DNA lesions are caused by 5-azadC and if such are substrates for DNA repair. Here, we identify that 5-azadC induces DNA damage as measured by γ-H2AX and 53BP1 foci. Furthermore, 5-azadC induces radial chromosomes and chromatid breaks that depend on active replication, which altogether suggest that trapped DNMT collapses oncoming replication forks into double-strand breaks. We demonstrate that RAD51-mediated homologous recombination (HR) is activated to repair 5-azadC collapsed replication forks. Fanconi anemia (FA) is a rare autosomal recessive disorder, and deaths are often associated with leukemia. Here, we show that FANCG-deficient cells fail to trigger HR-mediated repair of 5-azadC-induced lesions, leading to accumulation of chromatid breaks and inter-chromosomal radial fusions as well as hypersensitivity to the cytotoxic effects of 5-azadC. These data demonstrate that the FA pathway is important to protect from 5-azadC-induced toxicity. Altogether, our data demonstrate that cytotoxicity of the epigenetic drug 5-azadC can, at least in part, be explained by collapsed replication forks requiring FA-mediated HR for repair.


Assuntos
Azacitidina/análogos & derivados , Replicação do DNA/efeitos dos fármacos , Inibidores Enzimáticos/toxicidade , Proteína do Grupo de Complementação G da Anemia de Fanconi/fisiologia , Reparo de DNA por Recombinação , Animais , Azacitidina/toxicidade , Linhagem Celular , Cromátides/efeitos dos fármacos , Cricetinae , Cricetulus , Quebras de DNA , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Decitabina , Leupeptinas/farmacologia , Inibidores de Proteassoma/farmacologia
13.
Mutat Res ; 738-739: 45-51, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22921906

RESUMO

In the last years a number of reports have shown that the so-called topoisomerase II (topo II) catalytic inhibitors are able to induce DNA and chromosome damage, an unexpected result taking into account that they do not stabilize topo II-DNA cleavable complexes, a feature of topo II poisons such as etoposide and amsacrine. Merbarone inhibits the catalytic activity of topo II by blocking DNA cleavage by the enzyme. While it was first reported that merbarone does not induce genotoxic effects in mammalian cells, this has been challenged by reports showing that the topo II inhibitor induces efficiently chromosome and DNA damage, and the question as to a possible behavior as a topo II poison has been put forward. Given these contradictory results, and the as yet incomplete knowledge of the molecular mechanism of action of merbarone, in the present study we have tried to further characterize the mechanism of action of merbarone on cell proliferation, cell cycle, as well as chromosome and DNA damage in cultured CHO cells. Merbarone was cytotoxic as well as genotoxic, inhibited topo II catalytic activity, and induced endoreduplication. We have also shown that merbarone-induced DNA damage depends upon ongoing DNA synthesis. Supporting this, inhibition of DNA synthesis causes reduction of DNA damage and increased cell survival.


Assuntos
Dano ao DNA/efeitos dos fármacos , Endorreduplicação/efeitos dos fármacos , Tiobarbitúricos/toxicidade , Inibidores da Topoisomerase II/toxicidade , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cricetinae , Cricetulus
14.
BMC Plant Biol ; 12: 111, 2012 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-22824090

RESUMO

BACKGROUND: Zinc (Zn) deficiency is one of the most widespread mineral nutritional problems that affect normal development in plants. Because Zn cannot passively diffuse across cell membranes, it must be transported into intracellular compartments for all biological processes where Zn is required. Several members of the Zinc-regulated transporters, Iron-regulated transporter-like Protein (ZIP) gene family have been characterized in plants, and have shown to be involved in metal uptake and transport. This study describes the first putative Zn transporter in grapevine. Unravelling its function may explain an important symptom of Zn deficiency in grapevines, which is the production of clusters with fewer and usually smaller berries than normal. RESULTS: We identified and characterized a putative Zn transporter from berries of Vitis vinifera L., named VvZIP3. Compared to other members of the ZIP family identified in the Vitis vinifera L. genome, VvZIP3 is mainly expressed in reproductive tissue - specifically in developing flowers - which correlates with the high Zn accumulation in these organs. Contrary to this, the low expression of VvZIP3 in parthenocarpic berries shows a relationship with the lower Zn accumulation in this tissue than in normal seeded berries where its expression is induced by Zn. The predicted protein sequence indicates strong similarity with several members of the ZIP family from Arabidopsis thaliana and other species. Moreover, VvZIP3 complemented the growth defect of a yeast Zn-uptake mutant, ZHY3, and is localized in the plasma membrane of plant cells, suggesting that VvZIP3 has the function of a Zn uptake transporter. CONCLUSIONS: Our results suggest that VvZIP3 encodes a putative plasma membrane Zn transporter protein member of the ZIP gene family that might play a role in Zn uptake and distribution during the early reproductive development in Vitis vinifera L., indicating that the availability of this micronutrient may be relevant for reproductive development.


Assuntos
Proteínas de Transporte/genética , Vitis/genética , Zinco/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Transporte Biológico/genética , Proteínas de Transporte/metabolismo , DNA Complementar/genética , DNA Complementar/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Teste de Complementação Genética , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Dados de Sequência Molecular , Mutação , Cebolas/genética , Cebolas/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , RNA de Plantas/genética , Proteínas Recombinantes de Fusão , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência , Vitis/crescimento & desenvolvimento , Vitis/metabolismo , Zinco/análise , Zinco/farmacologia
15.
Viruses ; 4(2): 200-10, 2012 02.
Artigo em Inglês | MEDLINE | ID: mdl-22470832

RESUMO

Human rhinovirus (HRV) is a leading cause of acute respiratory infection (ARI) in young children and infants worldwide and has a high impact on morbidity and mortality in this population. Initially, HRV was classified into two species: HRV-A and HRV-B. Recently, a species called HRV-C and possibly another species, HRV-D, were identified. In Mexico, there is little information about the role of HRV as a cause of ARI, and the presence and importance of species such as HRV-C are not known. The aim of this study was to determine the clinical characteristics and genetic variability of HRV in Mexican children. Genetic characterization was carried out by phylogenetic analysis of the 5'-nontranslated region (5'-NTR) of the HRV genome. The results show that the newly identified HRV-C is circulating in Mexican children more frequently than HRV-B but not as frequently as HRV-A, which was the most frequent species. Most of the cases of the three species of HRV were in children under 2 years of age, and all species were associated with very mild and moderate ARI.


Assuntos
Resfriado Comum/patologia , Resfriado Comum/virologia , RNA Viral/genética , Rhinovirus/classificação , Rhinovirus/genética , Regiões 5' não Traduzidas , Distribuição por Idade , Criança , Pré-Escolar , Análise por Conglomerados , Resfriado Comum/epidemiologia , Feminino , Humanos , Lactente , Masculino , México/epidemiologia , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Rhinovirus/patogenicidade , Análise de Sequência de DNA
16.
Plant Cell Physiol ; 53(2): 485-94, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22247248

RESUMO

Boron (B) is an essential micronutrient for normal development of roots, shoots and reproductive tissues in plants. Due to its role in the structure of rhamnogalacturonan II, a polysaccharide required for pollen tube growth, B deficiency has been associated with the occurrence of parthenocarpic seedless grapes in some varieties of Vitis vinifera L. Despite that, it is unclear how B is mobilized and accumulated in reproductive tissues. Here we describe the characterization of an efflux B transporter, VvBOR1, homolog to AtBOR1, which is involved in B xylem loading in Arabidopsis thaliana roots. VvBOR1-green fluorescent protein (GFP) fusion protein expressed in A. thaliana localizes in the proximal plasma membrane domain in root pericycle cells, and VvBOR1 overexpression restores the wild-type phenotype in A. thaliana bor1-3 mutant plants exposed to B deficiency. Complementation of a mutant yeast strain indicates that VvBOR1 corresponds to a B efflux transporter. Transcriptional analyses during grapevine reproductive development show that the VvBOR1 gene is preferentially expressed in flowers at anthesis and a direct correlation between the expression pattern and B content in grapes was established, suggesting the involvement of this transporter in B accumulation in grapevine berries.


Assuntos
Antiporters/metabolismo , Boro/metabolismo , Proteínas de Plantas/metabolismo , Vitis/genética , Sequência de Aminoácidos , Antiporters/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Flores/metabolismo , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Teste de Complementação Genética , Proteínas de Fluorescência Verde/metabolismo , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/genética , Raízes de Plantas/citologia , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Alinhamento de Sequência , Vitis/metabolismo
17.
Mutat Res ; 694(1-2): 45-52, 2010 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-20883705

RESUMO

Catenations between sister chromatids result from DNA replication and must be resolved to ensure proper chromatid segregation in mitosis. Functionally active Topoisomerase II (Topo II), through its mechanism of concerted breaking and rejoining of double stranded DNA, is required to carry out this fundamental process. In previous studies we have shown that modifications in DNA sequence by halogenated pyrimidines and by the demethylating agent 5-azacytidine leads to malfunction of Topo II that results in an increased yield of endorreduplicated cells as a result of segregation failure. In the present work we have evaluated the possible influence of the methylating agent Budesonide to modify the frequency of endoreduplicated cells in AA8 Chinese hamster cell population. Our results seem to indicate that when Budesonide was administered for two consecutive cell cycles did induce an increase in the yield of endoreduplicated cells, as previously observed for the hypomethylating agent 5-azaC. We have also examined the possible relationship between extensive hypermethylation induced by Budesonide in DNA and stabilization of cleavable complexes by m-AMSA. Taken as a whole, our results show that the degree of methylation in DNA correlates with the effectiveness of m-AMSA to stabilize the Topo II-DNA complexes and to induce DNA cleavage. These findings evidence for the first time the functional importance of DNA hyper- and hypomethylation changes as epigenetic factors able to modulate Topo II activity for proper chromosome segregation.


Assuntos
Budesonida/farmacologia , Metilação de DNA , DNA Topoisomerases Tipo II/genética , Animais , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Ciclo Celular , Núcleo Celular/metabolismo , Cromossomos/ultraestrutura , Cricetinae , Replicação do DNA , Citometria de Fluxo/métodos , Glucocorticoides/farmacologia , Humanos , Microscopia de Fluorescência/métodos , Mitose
18.
Toxicol In Vitro ; 23(6): 1110-5, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19490938

RESUMO

Ochratoxin A (OTA), a known nephrotoxin and carcinogenic mycotoxin, was investigated to examine its effectiveness to induce cytotoxicity and DNA damage (Comet assay), as well as its possible inhibition of topoisomerase II (topo II) catalytic activity in cultured Chinese hamster ovary (CHO) cells. The analysis of OTA-induced DNA strand breaks as well as the flow cytometric assessment of polyploidy has provided evidence that is consistent with the idea of a mixed mode of action of the mycotoxin: in addition to its genotoxic activity, OTA may also interfere with chromosome distribution during cell division.


Assuntos
Micotoxinas/toxicidade , Ocratoxinas/toxicidade , Poliploidia , Inibidores da Topoisomerase II , Animais , Células CHO , Células Cultivadas , Ensaio Cometa , Cricetinae , Cricetulus , Quebras de DNA/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , DNA Topoisomerases Tipo II/metabolismo , Citometria de Fluxo
19.
Toxicol In Vitro ; 23(3): 432-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19444924

RESUMO

Aneugenic compounds are able to cause chromosome missegregation during mitosis which results in aneuploidy in cells that are able to survive. Aneuploidy is considered a key early condition in the progression from a normal cell into a cancerous cell. The possible toxicity of therapeutic lithium has raised concern because lithium salts are currently widely prescribed as an efficient treatment of manic-depressive disorders and numerous undesirable side effects of long-term treatment have been reported to date. We have observed a dose-dependent cytotoxic effect of both Li2CO3 and LiCl in AA8 CHO cells, while no genotoxic damage was detected. Mitotic abnormalities such as multipolar anaphases and lagging chromosomes leading to the presence of micronuclei in the next interphase were frequently observed after treatment with lithium salts. Thus, the effectiveness of both lithium salts to induce alterations in the normal segregation of chromosomes could be ascribed to interference with proteins involved in the organization and/or function of the mitotic apparatus.


Assuntos
Aneugênicos/toxicidade , Aneuploidia , Antimaníacos/toxicidade , Carbonato de Lítio/toxicidade , Cloreto de Lítio/toxicidade , Mitose/efeitos dos fármacos , Animais , Células CHO , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Dano ao DNA , Relação Dose-Resposta a Droga , Micronúcleos com Defeito Cromossômico/induzido quimicamente
20.
Mutagenesis ; 24(3): 237-44, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19201781

RESUMO

Methylation of cytosine in CpG sequences of the DNA in mammalian cells is an epigenetic feature regulated very exactly that bears importance for events like gene expression, DNA replication, transcription and genetic imprinting. Changes in the DNA methylation pattern, both hypermethylation and hypomethylation, have been observed in the carcinogenic process. These changes, in general, influence the DNA conformation in such a way that certain proteins are disturbed in their interactions with the molecule. In this paper, we investigated in cultured Chinese hamster ovary cells the influence of hypomethylation induced by the substitution of 5-aza-2'-deoxycytidine for cytidine in DNA on topoisomerase type I (topo I) function, measured as the capacity of the enzyme inhibitor camptothecin (CPT) to stabilize the topoisomerase-DNA complexes and to induce DNA strand breakage. Our results demonstrate that the degree of methylation in DNA correlates with the effectiveness of CPT to stabilize the topo I-DNA complexes and to induce DNA cleavage. A protective effect of hypomethylation, as a whole, has been observed.


Assuntos
Azacitidina/análogos & derivados , Camptotecina/farmacologia , Quebras de DNA/efeitos dos fármacos , Metilação de DNA/fisiologia , DNA Topoisomerases Tipo I/metabolismo , Inibidores Enzimáticos/farmacologia , Epigênese Genética/fisiologia , Animais , Azacitidina/metabolismo , Células CHO , Ensaio Cometa , Cricetinae , Cricetulus , Decitabina , Eletroforese em Gel de Campo Pulsado , Inibidores da Topoisomerase I
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