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1.
Semin Oncol Nurs ; 39(4): 151418, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37045645

RESUMO

OBJECTIVES: To identify, critically appraise, and synthesize the available evidence on the effectiveness of digital health interventions to improve the quality of life or any of its four dimensions (physical, psychological, social, and spiritual) in women survivors of breast cancer who are in the extended or permanent survival stage. DATA SOURCES: Systematic review-Four databases were searched: PubMed, CINAHL, PsycINFO, and Web of Science. CONCLUSION: The clinical evidence shows a positive relationship or association between eHealth use and improved quality of life in breast cancer survivors at extended or permanent survival stage. However, the findings point to a deficit in the assessment of the social and spiritual domains that play a fundamental role in the quality of life of survivors. IMPLICATION FOR NURSING PRACTICE: The findings found reflect implications of great value for nursing practice because these professionals are the main users of digital health tools to provide them to patients. Using these digital tools contributes to improving evidence-based practice and providing greater efficiency and effectiveness in the care of long-term cancer survivors.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Telemedicina , Humanos , Feminino , Sobreviventes de Câncer/psicologia , Neoplasias da Mama/terapia , Qualidade de Vida , Sobreviventes
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120063, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34153547

RESUMO

The present work reports the effects of meso-tetrakis (4-sulfonatophenyl) porphyrin (TPPS4) aggregation on its excited states absorption spectra, triplet states quenching by molecular oxygen and singlet oxygen production. Experimental techniques such as optical absorption, Z-scan with a white light continuum source and the Laser Flash Photolysis were used to fulfil the study. J-aggregates possess reverse saturable absorption in the 505-660 nm spectral range with a peak centered close to 540 nm. These facts together with their fast relaxation time suggest that they can be employed as material for ultrafast optical limiting and switching. Even though aggregation reduces the porphyrin excited-state lifetimes and quantum yields, it does not reduce the probability of the contact between the quencher and the excited aggregate. Aggregation does not change the contribution of energy transfer mechanisms to triplet state quenching by molecular oxygen. The production of singlet oxygen, the intense absorption in the phototherapeutic window and the high efficiency of conversion of light energy into heat, allow consider J-aggregates as a theranostic agent for photomedicine. It is proposed to use J-aggregates for diagnostics by photoacoustic images and in combination with a near-infrared photodynamic/photothermal dual mode therapy, thus improving synergistically the therapeutic response.


Assuntos
Porfirinas , Oxigênio Singlete , Cinética , Oxigênio
3.
Trop Anim Health Prod ; 52(6): 3241-3250, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32783132

RESUMO

The objective of this research was to evaluate the productive and reproductive characteristics of the Caqueteño Creole cattle breed. Data was taken from 655 animals organized into 6 groups: group 1 (n = 185), pure Caqueteño Creole cattle breed (Caqueteño); group 2 (n = 34), Caqueteño Creole cattle breed crossing for multiracial animals (Caqueteño 50% × multiracial 50%); group 3 (n = 10) (Caqueteño 75% × Bos indicus 25%); group 4 (n = 56), crossbreed F1 (Bos taurus × B. indicus); group 5 (n = 168), animals with B. taurus percentage greater than 50% (B. taurus > 50%); group 6 (n = 202), animals with B. indicus percentage greater than 50% (B. indicus > 50%). Subsequently were done descriptive statistics and analysis of variance (ANOVA) with the LSD Fisher test (P < 0.05), with the software InfoStat version 2018. A significant difference was found (P < 0.05); in weight at birth (WB), Caqueteño presented the smallest value (29.8 kg); in daily weight gain (DWG), weight adjusted at 9 months (W9), and weight adjusted at 18 months (W18), Caqueteño presented highest values corresponding to 574.5 g/day, 183.0 kg, and 343.6 kg, respectively; in age at the first service (AFS), the lowest value was obtained by B. taurus × B. indicus (24.5 months), and in calving interval (CI), no significant differences were found (P > 0.05). In conclusion, the Caqueteño Creole cattle breed is efficient in the productive variables (daily weight gain, adjusted weight at 9 and 18 months); in age at the first service, the F1 group indicated precocity, followed by Caqueteño Creole.


Assuntos
Peso Corporal , Bovinos/fisiologia , Reprodução , Animais , Bovinos/crescimento & desenvolvimento , Colômbia , Feminino , Masculino , Aumento de Peso
4.
Phys Chem Chem Phys ; 22(29): 16672-16680, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32658238

RESUMO

The wettability of graphene has been a topic under constant discussion in the literature since 2012. In this work we measured the contact angle (CA) of six different types of substrates (glass, quartz, Si3N4, Si/SiO2, sapphire and Si) with varying dielectric constants and surface roughnesses in order to calculate the surface free energy of graphene films to evaluate how the wetting properties of graphene-coated substrates are changed according to the underlying substrate. We used a residual-free transfer process to remove the high-quality graphene (CVD-Gr) grown onto copper foil. Afterwards, we performed an inert thermal treatment (Ar, at 300 °C for 30 minutes) to remove airborne contaminants from the graphene surface and evaluate the roughness of substrates by atomic force microscopy, the advancing and receding contact angles of two liquids (water and ethylene glycol), hysteresis, and surface free energy (polar and dispersive components) calculations. The presence of high-quality monolayer graphene (free of any air contaminants, polymer residues, etc.) led to a common wettability behaviour for all coated surfaces, regardless of the nature of the underlying substrate. This result can be understood in terms of the screening of van der Waals and dipole interactions by the electrons in graphene.

5.
Clín. investig. arterioscler. (Ed. impr.) ; 32(3): 101-110, mayo-jun. 2020. tab
Artigo em Espanhol | IBECS | ID: ibc-193354

RESUMO

ANTECEDENTES Y OBJETIVO: Los datos sobre la distribución de las dislipidemias en Colombia son limitados. El objetivo primario de este estudio fue describir la frecuencia de las dislipidemias; los objetivos secundarios fueron: la frecuencia de comorbilidades cardiovasculares, el uso de estatinas y otros hipolipemiantes, la frecuencia de intolerancia a estatinas, el porcentaje de pacientes en metas de c-LDL, y estimar la distribución del riesgo cardiovascular (RCV). MATERIALES Y MÉTODOS: Estudio transversal con recolección de datos retrospectiva que incluyó a 461 pacientes con diagnóstico de dislipidemia tratados en 17 centros cardiovasculares de alta complejidad en las 6 principales áreas geográficas y económicas de Colombia. RESULTADOS: La media (DE) de edad de los pacientes incluidos fue de 66,4 (±12,3) años. El 53,4% (246) eran mujeres. Las dislipidemias se distribuyeron así: dislipidemia mixta (51,4%), hipercolesterolemia (41,0%), hipertrigliceridemia (5,4%), hipercolesterolemia familiar (3,3%) y c-HDL bajo (0,7%). El medicamento más prescrito fue atorvastatina (75,7%), seguido de rosuvastatina (24,9%). El 55% del total de pacientes y el 28,6% de aquellos con enfermedad coronaria no estaban en metas de c-LDL a pesar del tratamiento. La frecuencia de intolerancia a estatinas fue del 2,6%. CONCLUSIONES: La dislipidemia mixta y la hipercolesterolemia son las dislipidemias más frecuentes. Un porcentaje considerable de pacientes en tratamiento, incluidos aquellos con enfermedad coronaria, no lograron sus objetivos de c-LDL. Este inadecuado control lipídico influye en el RCV y requiere un cambio en las estrategias terapéuticas, intensificando el tratamiento con estatinas o adicionando nuevos fármacos en los pacientes con mayor RCV


BACKGROUND AND OBJECTIVE: Data is scarce on the distribution of different types of dyslipidaemia in Colombia. The primary objective was to describe the frequency of dyslipidaemias. The secondary objectives were: frequency of cardiovascular comorbidity, statins and other lipid-lowering drugs use, frequency of statins intolerance, percentage of patients achieving c-LDL goals, and distribution of cardiovascular risk (CVR). MATERIALS AND METHODS: Cross-sectional study with retrospective data collection from 461 patients diagnosed with dyslipidaemia and treated in 17 highly specialised centres distributed into six geographic and economic regions of Colombia. RESULTS: Mean (SD) age was 66.4 (±12.3) years and 53.4% (246) were women. Dyslipidaemias were distributed as follows in order of frequency: mixed dyslipidaemia (51.4%), hypercholesterolaemia (41.0%), hypertriglyceridaemia (5.4%), familial hypercholesterolaemia (3.3%), and low c-HDL (0.7%). The most prescribed drugs were atorvastatin (75.7%) followed by rosuvastatin (24.9%). As for lipid control, 55% of all patients, and 28.6% of those with coronary heart disease, did not achieve their personal c-LDL goal despite treatment. The frequency of statin intolerance was 2.6% in this study. CONCLUSIONS: Mixed dyslipidaemia and hypercholesterolaemia are the most frequent dyslipidaemias in Colombia. A notable percentage of patients under treatment with lipid-lowering drugs, including those with coronary heart disease, did not achieve specific c-LDL goals. This poor lipid control may worsen patient's CVR, so that therapeutic strategies need to be changed, either with statin intensification or addition of new drugs in patients with higher CVR


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Dislipidemias/terapia , Dislipidemias/epidemiologia , Comorbidade , Colômbia/epidemiologia , Doenças Cardiovasculares/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipolipemiantes/uso terapêutico , Estudos Transversais , Dislipidemias/diagnóstico , Hipercolesterolemia/tratamento farmacológico , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Hipertrigliceridemia/tratamento farmacológico
6.
Clin Investig Arterioscler ; 32(3): 101-110, 2020.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32284160

RESUMO

BACKGROUND AND OBJECTIVE: Data is scarce on the distribution of different types of dyslipidaemia in Colombia. The primary objective was to describe the frequency of dyslipidaemias. The secondary objectives were: frequency of cardiovascular comorbidity, statins and other lipid-lowering drugs use, frequency of statins intolerance, percentage of patients achieving c-LDL goals, and distribution of cardiovascular risk (CVR). MATERIALS AND METHODS: Cross-sectional study with retrospective data collection from 461 patients diagnosed with dyslipidaemia and treated in 17 highly specialised centres distributed into six geographic and economic regions of Colombia. RESULTS: Mean (SD) age was 66.4 (±12.3) years and 53.4% (246) were women. Dyslipidaemias were distributed as follows in order of frequency: mixed dyslipidaemia (51.4%), hypercholesterolaemia (41.0%), hypertriglyceridaemia (5.4%), familial hypercholesterolaemia (3.3%), and low c-HDL (0.7%). The most prescribed drugs were atorvastatin (75.7%) followed by rosuvastatin (24.9%). As for lipid control, 55% of all patients, and 28.6% of those with coronary heart disease, did not achieve their personal c-LDL goal despite treatment. The frequency of statin intolerance was 2.6% in this study. CONCLUSIONS: Mixed dyslipidaemia and hypercholesterolaemia are the most frequent dyslipidaemias in Colombia. A notable percentage of patients under treatment with lipid-lowering drugs, including those with coronary heart disease, did not achieve specific c-LDL goals. This poor lipid control may worsen patient's CVR, so that therapeutic strategies need to be changed, either with statin intensification or addition of new drugs in patients with higher CVR.


Assuntos
Dislipidemias/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Hipolipemiantes/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , LDL-Colesterol/sangue , Colômbia/epidemiologia , Estudos Transversais , Dislipidemias/epidemiologia , Dislipidemias/fisiopatologia , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Hipolipemiantes/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
Phys Chem Chem Phys ; 21(42): 23521-23532, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31617508

RESUMO

Hybrid van der Waals heterojunctions based on organic polymers and 2D materials have emerged as a promising solution for developing more efficient optoelectronic devices. Herein, we investigated the charge transfer (CT) dynamics at the interface of the poly[3-hexylthiophene-2,5-diyl] (P3HT) organic polymer and a MoS2 monolayer. A global picture of the charge transfer dynamics of a P3HT/MoS2/SiO2 heterojunction was elucidated from photoluminescence (PL) spectroscopy and the fluorescence lifetime decay profile. Rapid interfacial charge transfer between P3HT and MoS2 was indicated by strong PL quenching and a reduction in the average fluorescence lifetime (τav) of the P3HT/MoS2/SiO2 heterojunction. The role of specific electronic states in the interfacial CT process was investigated by applying the core hole clock approach. CT times (τCT) on femtosecond and sub-femtosecond timescales were estimated using the S1s core-hole lifetime as the internal clock. Sub-femtosecond CT was observed for electrons excited to S3pz (0.34 fs) electronic states of MoS2 and to π* (C-C) (0.45 fs) electronic states of P3HT in the P3HT/MoS2/SiO2 heterojunction. These fast bidirectional CT processes result from strong coupling between these two electronic states in the P3HT/MoS2/SiO2 heterostructure. However, the reduction of the τCT values in the heterojunction compared with those of the isolated films shows that interfacial CT from the P3HT species to MoS2 is more efficient. Interfacial CT was not observed for electrons excited to electronic states S3px,y (MoS2) and σ* (S-C) (P3HT). We conclude that the π* (C-C) electronic state of the P3HT species is the main pathway for interfacial ultrafast CT in a P3HT/MoS2/SiO2 heterojunction.

8.
Nanoscale Res Lett ; 13(1): 40, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29404784

RESUMO

Interaction between porphyrins and quantum dots (QD) via energy and/or charge transfer is usually accompanied by reduction of the QD luminescence intensity and lifetime. However, for CdSe/ZnS-Cys QD water solutions, kept at 276 K during 3 months (aged QD), the significant increase in the luminescence intensity at the addition of meso-tetrakis (p-sulfonato-phenyl) porphyrin (TPPS4) has been observed in this study. Aggregation of QD during the storage provokes reduction in the quantum yield and lifetime of their luminescence. Using steady-state and time-resolved fluorescence techniques, we demonstrated that TPPS4 stimulated disaggregation of aged CdSe/ZnS-Cys QD in aqueous solutions, increasing the quantum yield of their luminescence, which finally reached that of the fresh-prepared QD. Disaggregation takes place due to increase in electrostatic repulsion between QD at their binding with negatively charged porphyrin molecules. Binding of just four porphyrin molecules per single QD was sufficient for total QD disaggregation. The analysis of QD luminescence decay curves demonstrated that disaggregation stronger affected the luminescence related with the electron-hole annihilation in the QD shell. The obtained results demonstrate the way to repair aged QD by adding of some molecules or ions to the solutions, stimulating QD disaggregation and restoring their luminescence characteristics, which could be important for QD biomedical applications, such as bioimaging and fluorescence diagnostics. On the other hand, the disaggregation is important for QD applications in biology and medicine since it reduces the size of the particles facilitating their internalization into living cells across the cell membrane.

9.
Colomb. med ; 48(4): 191-203, Oct.-Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-890878

RESUMO

Abstract The prevalence of Prediabetes in Colombia is high, and despite being recognized and categorized in the main Medical Guidelines and included in the International Classification of Diseases in Colombia, knowledge and awareness of it is limited amongst healthcare professionals and in the community. Our expert group recommends that educational programs emphasize a global approach to risk which includes a recognition of the importance of prediabetes and its evaluation along with and other risk factors such as a family history of DM2, overweight and obesity, dislipidemia and hypertension. Studies conducted in Colombia demonstrate the value of the FINDRIS questionnaire as a tool to identify subjects at risk of prediabetes and DM2, and we recommend that it should be systematic applied throughout the country as part of government policy. Prediabetes progresses to DM2 at an annual rate of 10%, but it has also been shown that prediabetes is an independent risk factor for cardiovascular outcomes. On this basis, the Committee recommends that once prediabetes is detected and diagnosed, immediate management of the disease begins through lifestyle changes, with follow up assessments performed at 3 and 6 months. If the patient does not respond with a weight loss of at least 5% and if the HbA1C values ​​are not normalized, pharmacological management should be initiated with a metformin dose of 500 mg / day, increasing up to 1,500 - 1,700 mg / day, according to tolerance.


Resumen La prevalencia de Prediabetes en Colombia es alta y a pesar estar reconocida y categorizada en las principales Guías Médicas y estar incluida en la Clasificación Internacional de Enfermedades vigente en Colombia, el conocimiento que de ella tiene el equipo de salud y la comunidad es limitada. El grupo de expertos recomienda que en los programas educativos se insista en un enfoque global del riesgo incluyendo la importancia de conocer y evaluar la prediabetes y otros factores de riesgo como antecedentes familiares de DM2, sobrepeso y obesidad, dislipidemia e hipertensión. Estudios realizados en Colombia demuestran la utilidad de la encuesta FINDRIS para identificar sujetos en riesgo de prediabetes y DM2 por lo que se recomienda que la aplicación del FINDRIS debe ser una política gubernamental y aplicada en todo el país. La Prediabetes progresa hacia DM2 a una tasa anual del 10% y se ha demostrado que independientemente de esto la Prediabetes es un factor de riesgo para desenlaces cardiovasculares por lo que el Comité recomienda que una vez detectada y diagnosticada, se inicie el manejo inmediato a través de cambios en el estilo de vida y realizar valoración a los 3 y 6 meses. Si el paciente no responde con una pérdida de peso de al menos el 5% y si no se normalizan los valores de HbA1C, iniciar manejo farmacológico con una dosis de 500 mg/día de metformina, escalando hasta 1,500 - 1,700 mg/día, según tolerancia.


Assuntos
Humanos , Estado Pré-Diabético/epidemiologia , Guias de Prática Clínica como Assunto , Diabetes Mellitus Tipo 2/epidemiologia , Estado Pré-Diabético/etiologia , Estado Pré-Diabético/terapia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/epidemiologia , Redução de Peso , Prevalência , Fatores de Risco , Colômbia/epidemiologia , Progressão da Doença , Consenso , Hipoglicemiantes/administração & dosagem , Estilo de Vida , Metformina/administração & dosagem
10.
Photochem Photobiol Sci ; 16(7): 1071-1078, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28513644

RESUMO

The cytotoxicity of nitrofurantoin (NFT) in the dark and after light exposure (UVA irradiation, λ = 385 nm) was evaluated in murine melanoma B16F10 cells. NFT induces both cell proliferation and inhibition of cell viability. The dominance of one or the other effect depends on the drug concentration, incubation time (tinc) and irradiation dose. The uptake of NFT in these cells, as well as its photocytotoxicity, reaches saturation after 24 hours of incubation. The mechanism of cell death in the dark is associated with the enzymatic release of nitric oxide (NO). The increase of NFT cytotoxicity under light irradiation is associated with the increase of NO concentration due to photorelease. NO photorelease by NFT in solution was confirmed by chemiluminescence, while NO formation in cells was confirmed by fluorescence microscopy using DAF-2DA, a specific indicator of NO in living cells. The NFT does not enter nuclei, distributing preferentially in the cell cytoplasm, as shown by fluorescence microscopy.


Assuntos
Melanoma/tratamento farmacológico , Nitrofurantoína/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Raios Ultravioleta , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Melanoma/patologia , Camundongos , Nitrofurantoína/química , Fármacos Fotossensibilizantes/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
11.
Colomb Med (Cali) ; 48(4): 191-203, 2017 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-29662261

RESUMO

The prevalence of Prediabetes in Colombia is high, and despite being recognized and categorized in the main Medical Guidelines and included in the International Classification of Diseases in Colombia, knowledge and awareness of it is limited amongst healthcare professionals and in the community. Our expert group recommends that educational programs emphasize a global approach to risk which includes a recognition of the importance of prediabetes and its evaluation along with and other risk factors such as a family history of DM2, overweight and obesity, dislipidemia and hypertension. Studies conducted in Colombia demonstrate the value of the FINDRIS questionnaire as a tool to identify subjects at risk of prediabetes and DM2, and we recommend that it should be systematic applied throughout the country as part of government policy. Prediabetes progresses to DM2 at an annual rate of 10%, but it has also been shown that prediabetes is an independent risk factor for cardiovascular outcomes. On this basis, the Committee recommends that once prediabetes is detected and diagnosed, immediate management of the disease begins through lifestyle changes, with follow up assessments performed at 3 and 6 months. If the patient does not respond with a weight loss of at least 5% and if the HbA1C values ​​are not normalized, pharmacological management should be initiated with a metformin dose of 500 mg / day, increasing up to 1,500 - 1,700 mg / day, according to tolerance.


La prevalencia de Prediabetes en Colombia es alta y a pesar estar reconocida y categorizada en las principales Guías Médicas y estar incluida en la Clasificación Internacional de Enfermedades vigente en Colombia, el conocimiento que de ella tiene el equipo de salud y la comunidad es limitada. El grupo de expertos recomienda que en los programas educativos se insista en un enfoque global del riesgo incluyendo la importancia de conocer y evaluar la prediabetes y otros factores de riesgo como antecedentes familiares de DM2, sobrepeso y obesidad, dislipidemia e hipertensión. Estudios realizados en Colombia demuestran la utilidad de la encuesta FINDRIS para identificar sujetos en riesgo de prediabetes y DM2 por lo que se recomienda que la aplicación del FINDRIS debe ser una política gubernamental y aplicada en todo el país. La Prediabetes progresa hacia DM2 a una tasa anual del 10% y se ha demostrado que independientemente de esto la Prediabetes es un factor de riesgo para desenlaces cardiovasculares por lo que el Comité recomienda que una vez detectada y diagnosticada, se inicie el manejo inmediato a través de cambios en el estilo de vida y realizar valoración a los 3 y 6 meses. Si el paciente no responde con una pérdida de peso de al menos el 5% y si no se normalizan los valores de HbA1C, iniciar manejo farmacológico con una dosis de 500 mg/día de metformina, escalando hasta 1,500 - 1,700 mg/día, según tolerancia.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Guias de Prática Clínica como Assunto , Estado Pré-Diabético/epidemiologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Colômbia/epidemiologia , Consenso , Progressão da Doença , Humanos , Hipoglicemiantes/administração & dosagem , Estilo de Vida , Metformina/administração & dosagem , Estado Pré-Diabético/etiologia , Estado Pré-Diabético/terapia , Prevalência , Fatores de Risco , Redução de Peso
13.
Eur Biophys J ; 45(3): 219-27, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26518694

RESUMO

This study employed surface pressure isotherms and spectroscopic techniques to investigate the effect of quantum dots on the interaction between porphyrins and phospholipids using Langmuir monolayers and Langmuir-Blodgett films formed from negatively charged DMPA (the sodium salt of dimyristoyl-sn-glycero-phosphatidyl acid) and zwitterionic DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) as cell membrane models in the presence of 5,10,15,20-tetrakis(4-N-tetradecyl-pyridyl) porphyrin (TMPyP), 5,10,15,20-tetrakis(p-sulfonato-phenyl) porphyrin (TPPS4) and PEG-coated CdSe/ZnS quantum dots (QD). The porphyrins present at the monolayer subphase affected the organization of the lipids at the air/liquid interface, as shown by the changes in the surface pressure-surface area isotherms. QDs enhanced the interaction of TMPyP with DMPA, improving their transference from the liquid monolayers to solid supports. A higher amount of TMPyP was transferred to DMPA-Langmuir-Blodgett films when the QDs were present in the subphase as evidenced by the UV-Vis data. For DPPC the surface effects due to the presence of QDs are less evident.


Assuntos
Membrana Celular/química , Fosfolipídeos/química , Porfirinas/química , Pontos Quânticos/química
14.
Am J Physiol Renal Physiol ; 304(3): F289-99, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23097471

RESUMO

Hypertension affects one-third of the adult population of the world. The causes of hypertension are incompletely understood, but relative impairment of sodium excretion is central to its pathogenesis. Immune cell infiltration in the kidney is a constant finding in hypertension that in association with local angiotensin and oxidants causes a defect in sodium excretion. However, it is unclear if the T cell influx into the kidney responds to nonspecific chemokine cues or is due to antigen-driven immune attraction. We found that T cells in experimentally induced salt-driven hypertension present a CD4 clonal response to heat shock protein 70 (HSP70) that is overexpressed in the kidney. We used a highly preserved amino acid sequence within the HSP molecule to induce immune tolerance associated with the generation of IL-10 producing regulatory T cells. Immune tolerant rats to HSP70 developed minimal renal inflammation and were protected from the development of salt-sensitive hypertension. Adoptive transfer of T lymphocytes isolated from spleen of tolerized rats also reversed hypertension. HSP70 gene delivery to the renal vein of the kidneys of rats sensitized to HSP70 caused an increment in blood pressure in response to a high-salt diet. The HSP70 peptide used in this work induces a strong proliferative response in peripheral blood lymphocytes of patients with essential hypertension. These studies provide evidence that autoimmunity plays a role in salt-sensitive hypertension and identifies HSP70 expressed in the kidney as one key antigen. These findings raise the possibility of novel approaches to the treatment of this condition.


Assuntos
Autoimunidade/fisiologia , Proteínas de Choque Térmico HSP70/imunologia , Hipertensão/etiologia , Hipertensão/imunologia , Rim/metabolismo , Tolerância ao Sal/fisiologia , Adulto , Animais , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Feminino , Proteínas de Choque Térmico HSP70/farmacologia , Humanos , Hipertensão/fisiopatologia , Interleucina-10/metabolismo , Rim/imunologia , Rim/patologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Ratos , Ratos Wistar , Cloreto de Sódio na Dieta/efeitos adversos , Cloreto de Sódio na Dieta/farmacologia
15.
J Food Sci ; 76(2): C205-11, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21535736

RESUMO

UNLABELLED: A powerful technique was developed for the identification and quantification of 9 volatile compounds of beer, using headspace solid phase micro-extraction (HS/SPME) and gas chromatograph coupled to a mass spectrometer and a flame ionization detector (GC/MS/FID). Optimized parameters included type of fiber, desorption time, and exposure time. Optimization was achieved with standard solutions of the target compounds. All samples were analyzed in triplicate. An exposure time of 45 min with PDMS fiber in the sample headspace was enough to reach equilibrium of the phases. A desorption time of 15 min in the gas chromatograph injector was enough for the fiber to desorb the target compounds. It was found that less polar compounds were more readily absorbed by the fiber (for example, isoamyl acetate) than more polar compounds (for example, acetaldehyde), under the extraction conditions, due to the nature of the fiber. Extraction conditions are important criteria to perform a good quantification of volatile compounds. Concentrations found in sampled beer, for the compounds of interest, ranged between 0.32 and 41.7 ppm. Results show that the reproducibility of the technique depends on the compounds. Esters have higher values (RSD mean value 5.05%) than higher alcohols (RSD mean value 2.5%) and aldehydes (RSD 3.7%). The simplicity of the validated methodology enables its use as a regular quality control procedure for beer flavor analysis. PRACTICAL APPLICATION: This study describes a technique successfully used to identify and quantify volatiles of interest in beer that can be used for quality control purposes under normal brewery production conditions. The technique uses a gas chromatograph coupled to a mass spectrometer with a flame ionization detector.


Assuntos
Cerveja/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise , Álcoois/análise , Aldeídos/análise , Ésteres/análise , Fermentação , Ionização de Chama/métodos , Pentanóis/análise
16.
Toxicol Ind Health ; 26(3): 163-74, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20176775

RESUMO

Oxidative stress is an important mechanism in mercury poisoning. We studied the effect of uric acid, a natural and potent reactive oxygen species and peroxynitrite scavenger, in HgCl( 2)-induced nephrotoxicity. Rats were injected with a unique dose of HgCl(2) (2.5 mg/kg body weight, subcutaneously) and then vehicle (for 3 days, twice daily) or HgCl(2) (unique dose) and intraperitoneal uric acid suspension (250 mg/kg body weight, twice daily, for 3 days), and then killed at 24, 48 and 72 hours after HgCl(2) administration (n = 5 for each group). At the end of the experimental study, kidneys and blood samples were taken. Tissues were prepared and examined under light microscopy. Uric acid significantly prevented the increase in plasma levels of creatinine and blood urea nitrogen (BUN); it helped maintain systemic nitrate/nitrite concentration and total antioxidant capacity. Uric acid attenuated the increase of renal lipid peroxidation and it markedly diminished nitrotyrosine signal and histopathological changes as early as 24 hours after HgCl(2) administration. Uric acid did not prevent a decrease in beta-actin signal caused by mercuric chloride, but it promoted a faster recovery when compared to the HgCl(2) alone group. Our results indicate that UA could play a beneficial role against HgCl(2) toxicity by preventing systemic and renal oxidative stress and tissue damage.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Rim/efeitos dos fármacos , Cloreto de Mercúrio/toxicidade , Ácido Úrico/farmacologia , Injúria Renal Aguda/metabolismo , Análise de Variância , Animais , Western Blotting , Interações Medicamentosas , Injeções Subcutâneas , Rim/metabolismo , Masculino , Cloreto de Mercúrio/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Ácido Úrico/administração & dosagem
17.
Basic Clin Pharmacol Toxicol ; 105(6): 416-24, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19821833

RESUMO

In this work, we aimed to study the effect of uric acid on gentamicin-induced nephrotoxicity. Male Sprague-Dawley rats were assigned to one of six groups (six rats each) which received intraperitoneal injections for 9 days: (S) saline; (UA) Uric acid alone; (G) Gentamicin alone; (G + UA) Gentamicin + uric acid; (G rec) Gentamicin recovery and (G + UA rec) Gentamicin + uric acid recovery. In (G rec) and (G + UA rec), rats recovered for 7 days after the last injection. Urine and blood samples were taken on day 0 and at the end of every stage. Kidneys were harvested for histological scoring, determination of renal malondialdehyde (MDA), zymography and western blots for matrix metalloprotease (MMP)-2 and MMP-9. Uric acid alone did not provoke changes in biochemical and histological parameters when compared to controls. Gentamicin alone increased significantly plasma creatinine and blood urea nitrogen and caused a moderate histological damage. When combined with uric acid, these conditions worsened. MMP-9 activity and expression was decreased in rats from group G + UA as compared with rats from group G, while activity of MMP-2 was similarly increased in both groups when compared to controls. The increase in renal MDA induced by gentamicin was not altered when it was combined with uric acid. During the recovery stage, all biochemical parameters returned to normal levels, though a trend for delay of tubular damage recovery was observed in group G + UA rec when compared with group G rec. The results indicate that uric acid worsens gentamicin-induced nephrotoxicity. The mechanism is likely to implicate down-regulation of MMP-9.


Assuntos
Antibacterianos/toxicidade , Gentamicinas/toxicidade , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Insuficiência Renal/induzido quimicamente , Ácido Úrico/farmacologia , Animais , Rim/química , Rim/efeitos dos fármacos , Rim/enzimologia , Testes de Função Renal , Necrose Tubular Aguda/induzido quimicamente , Necrose Tubular Aguda/etiologia , Necrose Tubular Aguda/patologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Proteinúria/induzido quimicamente , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Insuficiência Renal/patologia , Substâncias Reativas com Ácido Tiobarbitúrico/química , Fatores de Tempo , Ácido Úrico/sangue , Ácido Úrico/urina
18.
Kidney Int Suppl ; (111): S55-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19034328

RESUMO

Renal tubulointerstitial inflammation is a constant feature of experimental models of hypertension and likely plays a role in the pathogenesis of salt-sensitive hypertension. We have previously raised the possibility that the immune cell infiltration is driven by a low grade autoimmune reactivity directed to or facilitated by renal heat shock protein over expression. The present studies were done to gain insight on possible cell-mediated immune mechanisms in experimental hypertension by determining the renal expression of HSP70 and the proliferation index of T lymphocytes cultured with HSP70. We studied male Sprague-Dawley rats with inhibition of nitric oxide (NO) synthase (n=6), protein overload (PO) proteinuria (n=7) and short-term angiotensin II (Ang II) infusion (n=5), and their corresponding control groups. Each model was associated with 2 to 4 fold increase (P<0.05-0.001) in renal HSP70 expression. T cells isolated from the spleens demonstrated a significant two- to nine-fold response compared to controls (P<0.05 or lower for each comparison) when cultured with HSP70. These studies suggest that autoimmunity to stress proteins is involved in the sustained low-grade inflammatory infiltration that occurs in the tubulointerstitial areas of the hypertensive kidney.


Assuntos
Proliferação de Células/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/farmacologia , Hipertensão/patologia , Hipertensão/fisiopatologia , Tolerância ao Sal/fisiologia , Linfócitos T/patologia , Angiotensina II/farmacologia , Animais , Autoimunidade/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Proteínas de Choque Térmico HSP70/metabolismo , Hipertensão/metabolismo , Rim/metabolismo , Rim/patologia , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Proteinúria/metabolismo , Proteinúria/fisiopatologia , Ratos , Ratos Sprague-Dawley , Tolerância ao Sal/imunologia , Linfócitos T/efeitos dos fármacos
19.
Dis Aquat Organ ; 68(2): 175-80, 2006 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-16532608

RESUMO

We have previously reported that white spot syndrome virus-infected Penaeus vannamei (also called Litopenaeus vannamei) maintained at 32 degrees C show higher survival rates and a significant increase in number of apoptotic cells when compared to infected shrimp kept at 26 degrees C. As apoptosis plays an important part in the antiviral response of invertebrates, we hypothesized that this process would reduce WSSV replication, allowing the shrimp to control the disease and survive. To test this hypothesis, shrimp were orally infected and maintained at either 26 degrees C (Group 1) or 32 degrees C (Group 2), DNA was extracted from haemolymph collected at various times from 6 to 216 h post-infection, and the number of viral units was quantified by real time PCR using SYBR Green. In parallel, histological examination was carried out to confirm the WSSV infection and to rule out concomitant diseases. Linear regression of real time PCR units (rtPCRU) of WSSV from Group 1 showed a significant increase with time post-infection (r2 = 0.7383; p < 0.001). Conversely, there was no increase in rtPCRU with time post-infection in Group 2 (r2 = 0.142), indicating that hyperthermia inhibited, either directly or indirectly, viral replication. In addition, comparison between the groups showed no difference in WSSV rtPCRU up to 48 h post-infection. After 72 h, shrimp from Group 1 had a significantly higher viral rtPCRU (ANOVA, p < 0.001). We conclude that hyperthermia-associated WSSV rtPCRU reduction could reflect either an increase in the shrimp antiviral response, or a direct negative effect on viral replication, or both.


Assuntos
Temperatura Alta , Penaeidae/virologia , Vírus da Síndrome da Mancha Branca 1/crescimento & desenvolvimento , Animais , Primers do DNA/química , Modelos Lineares , Reação em Cadeia da Polimerase/métodos , Carga Viral/veterinária , Vírus da Síndrome da Mancha Branca 1/genética , Vírus da Síndrome da Mancha Branca 1/patogenicidade
20.
Fertil Steril ; 82(6): 1550-5, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15589858

RESUMO

OBJECTIVE: To evaluate the effect of estrogen therapy (ET) on endothelial nitric oxide (NO) production and in flow-mediated vasodilation (FMV). DESIGN: Randomized, crossover, double-blind, placebo-controlled study. SETTING: Healthy postmenopausal women in an academic research environment. PATIENT(S): Forty postmenopausal women between 45 and 72 years of age. INTERVENTION(S): Women received ET or placebo during two periods of 12 weeks that were separated by 2 weeks of washout. MAIN OUTCOME MEASURE(S): Flow-mediated vasodilation, nitrite and nitrate, lipid profile, creatinine, and glucose were measured at weeks 12 and 24. Student's t or Wilcoxon tests were used for comparative analyses, and kappa test and limit analysis determined variability. RESULT(S): After placebo treatment, nitrate and nitrite mean concentration was 8.28 +/- 1.17 mmol/L; it increased to 62.6 +/- 12.82 mmol/L after ET. Percentage FMV was 18.8 +/- 2.58 after the placebo period and did not change after ET (20.1 +/- 1.92) in the whole sample, but in the subgroup (n = 15) of younger women (45-50 years of age), percentage FMV increased from 13.6 +/- 3.6 after the placebo period to 22.2 +/- 3.5 after ET. CONCLUSION(S): An increase in plasma concentrations of nitrite and nitrate after ET was observed in all the women studied, but the improvement in FMV was observed only in the younger ones. These age-related differences in FMV in response to ET must be further investigated.


Assuntos
Envelhecimento/fisiologia , Estrogênios Conjugados (USP)/uso terapêutico , Nitratos/sangue , Nitritos/sangue , Pós-Menopausa/fisiologia , Vasodilatação/efeitos dos fármacos , Idoso , Artéria Braquial/fisiologia , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa/sangue , Valores de Referência , Fluxo Sanguíneo Regional/fisiologia , Vasodilatação/fisiologia
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