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1.
Plant Biol (Stuttg) ; 25(6): 965-972, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37432095

RESUMO

Some chewing larvae are capable of inducing galls in the host vascular cylinder, e.g. Dasineura sp. (Cecidomyiidae) on Peumus boldus stems. Due to the medicinal and economic importance of P. boldus, the anatomical and functional implications of establishment of Dasineura sp. on P. boldus stems were investigated. We asked if establishment of Dasineura sp. in P. boldus stems induces abnormalities at the cellular and organizational level of the vascular system that increase during gall development in favour of the hydric status of the gall. Anatomical alterations induced in the stems during gall development were determined. Cytohistometric analyses in mature galls were compared to non-galled stems, and water potential and leaf area of non-galled stems were compared with galled stems. Dasineura sp. establishes in the vascular cambium, leading to delignification and rupture of xylem cells, inhibiting formation of phloem and perivascular sclerenchyma. Gall diameter increases together with larval feeding activity, producing a large larval chamber and numerous layers of nutritive tissue, vascular parenchyma, and sclerenchyma. These anatomical alterations do not affect the leaf area of galled stems but favour increased water flow towards these stems. The anatomical alterations induced by Dasineura sp. in P. boldus stems guarantee water and nutrient supply to the gall and larva. After the inducer exits stems, some host branches no longer have vascular connections with the plant body.


Assuntos
Peumus , Animais , Tumores de Planta , Larva , Folhas de Planta , Interações Hospedeiro-Parasita
3.
Tob Induc Dis ; 15: 41, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29142531

RESUMO

BACKGROUND: Several health organizations have adopted the 5A's brief intervention model (Ask, Advise, Assess, Assist, Arrange), based on evidence-based guidelines for smoking cessation. We examine individual, cognitive, behavioral, and organizational factors associated with the 5A's performance among clinical healthcare workers in Catalonia. We also investigate how these factors interact and potentially predict the implementation of each component of the 5A's. METHODS: A cross-sectional survey was conducted among clinical health workers enrolled in an online smoking cessation training course (n = 580). The survey included questions about individual characteristics as well as cognitive, behavioral, and organizational factors previously identified in research. We assessed self-reported performance of the 5A's, assessed on a scale from 0 to 10, and used Multivariate regression to examine factors associated with its performance. RESULTS: The performance means (standard deviation) were moderate for the first 3A's [Ask: 6.4 (3.1); Advise: 7.1 (2.7); Assess: 6.3 (2.8)] and low for the last 2A's [Assist: 4.4 (2.9); Arrange: 3.2 (3.3)]. We observed a high correlation between Assist and Arrange (r = 0.704, p < 0.001). Having positive experiences and feeling competent were positively associated with performing the 5A's model and having organizational support with Assist and Arrange. Personal tobacco use among healthcare workers was negatively associated with Advice and Arrange. CONCLUSIONS: Our study found that clinical healthcare workers do not perform the 5A's completely. The main barriers identified suggest the need of training and making available practical guidelines in healthcare services. Organizational support is essential for moving towards the implementation of Assist and Arrange.

4.
Cell Death Dis ; 4: e572, 2013 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-23559006

RESUMO

The ubiquitin-proteasome system and the autophagy-lysosome pathway are the two main mechanisms for eukaryotic intracellular protein degradation. Proteasome inhibitors are used for the treatment of some types of cancer, whereas autophagy seems to have a dual role in tumor cell survival and death. However, the relationship between both pathways has not been extensively studied in tumor cells. We have investigated both proteolytic systems in the human epithelial breast non-tumor cell line MCF10A and in the human epithelial breast tumor cell line MCF7. In basal condition, tumor cells showed a lower proteasome function but a higher autophagy activity when compared with MCF10A cells. Importantly, proteasome inhibition (PI) leads to different responses in both cell types. Tumor cells showed a dose-dependent glycogen synthase kinase-3 (GSK-3)ß inhibition, a huge increase in the expression of the transcription factor CHOP and an active processing of caspase-8. By contrast, MCF10A cells fully activated GSK-3ß and showed a lower expression of both CHOP and processed caspase-8. These molecular differences were reflected in a dose-dependent autophagy activation and cell death in tumor cells, while non-tumor cells exhibited the formation of inclusion bodies and a decrease in the cell death rate. Importantly, the behavior of the MCF7 cells can be reproduced in MCF10A cells when GSK-3ß and the proteasome were simultaneously inhibited. Under this situation, MCF10A cells strongly activated autophagy, showing minimal inclusion bodies, increased CHOP expression and cell death rate. These findings support GSK-3ß signaling as a key mechanism in regulating autophagy activation or inclusion formation in human tumor or non-tumor breast cells, respectively, which may shed new light on breast cancer control.


Assuntos
Autofagia/efeitos dos fármacos , Neoplasias da Mama/genética , Células Epiteliais/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/genética , Corpos de Inclusão/efeitos dos fármacos , Antineoplásicos/farmacologia , Autofagia/genética , Neoplasias da Mama/metabolismo , Caspase 8/genética , Caspase 8/metabolismo , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Corpos de Inclusão/metabolismo , Leupeptinas/farmacologia , Especificidade de Órgãos , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma/farmacologia , Proteólise/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Ubiquitina/genética , Ubiquitina/metabolismo
5.
Neurología (Barc., Ed. impr.) ; 28(2): 88-94, mar. 2013. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-110231

RESUMO

Introducción: El AD8 es un cuestionario al informador breve que puede ser autoaplicado y facilita la identificación de deterioro cognitivo (DC); nuestro objetivo es evaluar la utilidad diagnóstica (UD) de una versión espa˜nola. Material y métodos: Estudio transversal en una muestra clínica de díadas paciente/ informador, 330 sujetos con sospecha de DC o demencia (DEM) y 71 controles. Se ha evaluado la consistencia interna ( de Cronbach) y la validez (correlaciones parciales con estadio GDS, Fototest e índice funcional [IF]). La UD se ha evaluado para no DC vs DC (GDS 3-4) por medio del área bajo la curva ROC (aROC) y se ha considerado mejor punto de corte aquel que hacía máximo el índice de Youden. Resultados: En la muestra, 105 no tenían DC, 99 tenían DC sin DEM y 203 DEM. La consistencia interna es alta ( 0,90, IC del 95%, 0,89-0,92), al igual que las correlaciones con GDS (r = 0,72, p < 0,001), Fototest (r = —0,61, p < 0,001) e IF (r = 0,59, p < 0,001). El aROC del AD8 es 0,90 (IC del 95%, 0,86-0,93), sin diferencia significativa con la del Fototest (aROC 0,93, IC del 95%, 0,89-0,96); el mejor punto de corte es 3/4 con sensibilidad de 0,93 (IC del 95%, 0,88-0,96), especificidad de 0,81 (IC del 95%, 0,72-0,88) y el 88,8% de las clasificaciones correctas. El uso conjunto de AD8 y Fototest mejora de forma significativa la UD de ambos (aROC 0,96, IC del 95%, 0,93-0,98, p < 0,05). Conclusiones: La versión espa˜nola del AD8 conserva las cualidades psicométricas y la UD de la versión original; su uso combinado con el Fototest mejora de forma significativa la UD de ambos (AU)


Introduction: The AD8 is a brief informant-based questionnaire that may also be selfadministered, and which aids in identifying cognitive impairment (CI). Our goal is to assess the diagnostic accuracy (DA) of a Spanish version of that questionnaire. Material and methods: Cross-sectional study of a clinical sample of patient/informant dyads including 330 subjects with suspected CI or dementia (DEM) and 71 controls. We evaluated internal consistency (Cronbach’s alpha) and validity (partial correlations with GDS stage, Fototest results and functional index measure [FIM]). We assessed DA for CI vs no CI (GDS stage 3-4) using the area under the ROC curve (AUC), and the cut-off with the highest Youden index was determined to be optimal. Results: In the sample, 105 subjects had no CI, 99 had CI without DEM and 203 had DEM. Internal consistency was high ( 0.90, 95% confidence interval: 0.89-0.92), as were correlations with the GDS score (r=0.72, P<.001), Fototest results (r=−0.61, P<.001) and FIM (r=0.59, P<.001). The AUC for AD8 was 0.90 (95% confidence interval: 0.86-0.93), which was not significantly different from that of the Fototest (AUC 0.93, 95% confidence interval: 0.89-0.96). The optimal cut-off point was 3/4 with a sensitivity of 0.93 (95% confidence interval: 0.88-0.96) and a specificity of 0.81 (95% confidence interval: 0.72-0.88); 88.8% of the classifications were correct. Combined use of AD8 and the Fototest significantly improved the DA of both (AUC 0.96, 95% confidence interval: 0.93-0.98, P<.05). Conclusions: The Spanish version of the AD8 questionnaire preserves the psychometric qualities and DA of the original. Using this test in combination with the Fototest significantly increases the DA of both tests (AU)


Assuntos
Humanos , Demência/diagnóstico , Transtornos Cognitivos/diagnóstico , Psicometria/instrumentação , Sensibilidade e Especificidade , Inquéritos e Questionários , Testes Neuropsicológicos
6.
Neurologia ; 28(2): 88-94, 2013 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-22652137

RESUMO

INTRODUCTION: The AD8 is a brief informant-based questionnaire that may also be self-administered, and which aids in identifying cognitive impairment (CI). Our goal is to assess the diagnostic accuracy (DA) of a Spanish version of that questionnaire. MATERIAL AND METHODS: Cross-sectional study of a clinical sample of patient/informant dyads including 330 subjects with suspected CI or dementia (DEM) and 71 controls. We evaluated internal consistency (Cronbach's alpha) and validity (partial correlations with GDS stage, Fototest results and functional index measure [FIM]). We assessed DA for CI vs no CI (GDS stage 3-4) using the area under the ROC curve (AUC), and the cut-off with the highest Youden index was determined to be optimal. RESULTS: In the sample, 105 subjects had no CI, 99 had CI without DEM and 203 had DEM. Internal consistency was high (α 0.90, 95% confidence interval: 0.89-0.92), as were correlations with the GDS score (r=0.72, P<.001), Fototest results (r=-0.61, P<.001) and FIM (r=0.59, P<.001). The AUC for AD8 was 0.90 (95% confidence interval: 0.86-0.93), which was not significantly different from that of the Fototest (AUC 0.93, 95% confidence interval: 0.89-0.96). The optimal cut-off point was 3/4 with a sensitivity of 0.93 (95% confidence interval: 0.88-0.96) and a specificity of 0.81 (95% confidence interval: 0.72-0.88); 88.8% of the classifications were correct. Combined use of AD8 and the Fototest significantly improved the DA of both (AUC 0.96, 95% confidence interval: 0.93-0.98, P<.05). CONCLUSIONS: The Spanish version of the AD8 questionnaire preserves the psychometric qualities and DA of the original. Using this test in combination with the Fototest significantly increases the DA of both tests.


Assuntos
Transtornos Cognitivos/diagnóstico , Inquéritos e Questionários , Idoso , Idoso de 80 Anos ou mais , Transtornos Cognitivos/psicologia , Estudos Transversais , Interpretação Estatística de Dados , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes
7.
Lipids ; 40(5): 471-6, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-16094856

RESUMO

Paraoxonase 1 (PON 1) is an esterase with antioxidant properties that is present in HDL. Gln192Arg polymorphism (also named Q192R or Q/R) of the PON 1 gene that encodes this protein defines two alleles (Q and R). The R allele has been associated with higher cardiovascular risk. LDL size and susceptibility to oxidation also have been identified as cardiovascular risk factors. Our objective was to determine whether genetic variations in the Gln192Arg polymorphism influence LDL size and susceptibility to oxidation after the consumption of diets with different fat content. In our experiments, the participants (n = 98) underwent three 4-wk diets--one, saturated fat-enriched (SAT); another, monounsaturated fat-enriched (MONO); and a third, carbohydrate-enriched (CHO). We observed that LDL were smaller in the QQ group after the CHO diet vs. the SAT (P < 0.01) and MONO diets (P < 0.03). No differences in LDL size were found in QR/RR subjects. When we analyzed lag time of oxidation of LDL, we found that when carriers of the R allele (QR/RR) received the MONO diet, the lag period of LDL oxidation was longer as compared with the CHO diet. Otherwise, we found no differences in QQ homozygotes when we evaluated the lag time of oxidation of LDL after the three diets. These results suggest that the Glnl92Arg polymorphism of the paraoxonase gene influences LDL size and susceptibility to oxidation in response to diet.


Assuntos
Arildialquilfosfatase/genética , Carboidratos da Dieta/administração & dosagem , Lipoproteínas LDL/sangue , Adolescente , Adulto , Substituição de Aminoácidos , Arginina/genética , Gorduras na Dieta/administração & dosagem , Gorduras Insaturadas na Dieta/administração & dosagem , Feminino , Glutamina/genética , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético
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