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1.
ACS Sens ; 8(8): 2898-2920, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37556357

RESUMO

Over the past decade, molecular imprinting (MI) technology has made tremendous progress, and the advancements in nanotechnology have been the major driving force behind the improvement of MI technology. The preparation of nanoscale imprinted materials, i.e., molecularly imprinted polymer nanoparticles (MIP NPs, also commonly called nanoMIPs), opened new horizons in terms of practical applications, including in the field of sensors. Currently, hydrogels are very promising for applications in bioanalytical assays and sensors due to their high biocompatibility and possibility to tune chemical composition, size (microgels, nanogels, etc.), and format (nanostructures, MIP film, fibers, etc.) to prepare optimized analyte-responsive imprinted materials. This review aims to highlight the recent progress on the use of hydrogel MIP NPs for biosensing purposes over the past decade, mainly focusing on their incorporation on sensing devices for detection of a fundamental class of biomolecules, the peptides and proteins. The review begins by directing its focus on the ability of MIPs to replace biological antibodies in (bio)analytical assays and highlight their great potential to face the current demands of chemical sensing in several fields, such as disease diagnosis, food safety, environmental monitoring, among others. After that, we address the general advantages of nanosized MIPs over macro/micro-MIP materials, such as higher affinity toward target analytes and improved binding kinetics. Then, we provide a general overview on hydrogel properties and their great advantages for applications in the field of Sensors, followed by a brief description on current popular routes for synthesis of imprinted hydrogel nanospheres targeting large biomolecules, namely precipitation polymerization and solid-phase synthesis, along with fruitful combination with epitope imprinting as reliable approaches for developing optimized protein-imprinted materials. In the second part of the review, we have provided the state of the art on the application of MIP nanogels for screening macromolecules with sensors having different transduction modes (optical, electrochemical, thermal, etc.) and design formats for single use, reusable, continuous monitoring, and even multiple analyte detection in specialized laboratories or in situ using mobile technology. Finally, we explore aspects about the development of this technology and its applications and discuss areas of future growth.


Assuntos
Nanosferas , Nanoestruturas , Polímeros/química , Nanogéis , Hidrogéis/química
2.
J Chromatogr A ; 1663: 462726, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-34954536

RESUMO

A fast method based on reversed-phase ultra-high-performance liquid chromatography using evaporative light scattering detection (RP-UHPLC-ELSD) was developed for monitoring the intermediates and end products of biodiesel production. Gradient elution of water, acetonitrile, and a mixture of acetonitrile:2-propanol:n-hexane was used. With a minimal and easy sample preparation, fatty acid methyl esters (FAME), fatty acid ethyl esters (FAEE), free fatty acids (FFA), monoacylglycerols (MAG), diacylglycerols (DAG), and triacylglycerols (TAG) were successfully separated. The developed method was used to monitor an ethylic enzymatic transesterification of soybean oil and to characterize the ester content of methyl and ethyl biodiesel. The ester content obtained was compared with the reference method by gas chromatography and flame ionization detector (GC-FID), with similar results for both methyl and ethyl biodiesel. The presented method is a simple and fast alternative, a 17 min run, to monitor the transesterification process, simultaneously quantifying all the analytes produced in the reaction: biodiesel and its intermediates. Limits of detection (LOD, between 29 and 307 ng) and quantification (LOQ, between 48 and 614 ng), linearity (R2>0.99), precision (between 0.30 and 6.58%), and accuracy (between 81.6 and 119.9%) were determined for the twenty-one compounds.


Assuntos
Biocombustíveis , Cromatografia de Fase Reversa , Cromatografia Líquida de Alta Pressão , Ésteres , Ácidos Graxos
3.
Anal Chem ; 93(22): 7815-7824, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34038085

RESUMO

In this work, we describe an innovative methodology based on combined surface plasmon resonance (SPR) and electrochemical responses (eSPR) in the same immunoassay for screening CA 15-3 cancer biomarker with high sensitivity (and selectivity), in a very simple, label-free, accurate, and fully automated manner. Detection was achieved by performing two simple steps. In the first step, direct SPR was used to monitor CA 15-3 interaction with surface immobilized antibody. Two linear response ranges were obtained and the detection limit achieved is poor (LOD of 21 U mL-1). However, in the second detection step, electrochemical measurements at the SPR gold surface were performed to measure the decrease of redox probe peak current upon antigen-antibody interaction, providing a suitable amplification strategy to lower detection levels of CA 15-3 (LOD of 0.0998 U mL-1), without the need of additional complex and/or expensive amplification steps to enhance the sensitivity. Moreover, selectivity studies were performed against other common cancer biomarkers and the results showed that the eSPR immunosensor is selective for the CA 15-3 protein. Finally, the clinical applicability of the developed eSPR biosensing methodology was successfully applied to detect CA 15-3 in human serum samples at clinically relevant levels due to the high sensitivity of electrochemical readout. The same concept may be further extended to other proteins of interest.


Assuntos
Técnicas Biossensoriais , Ressonância de Plasmônio de Superfície , Eletroquímica , Ouro , Humanos , Imunoensaio , Limite de Detecção
4.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 37(5): 290-295, mayo 2019. tab, graf
Artigo em Inglês | IBECS | ID: ibc-189216

RESUMO

INTRODUCTION: The characteristics of D. fragilis infection are described, with special focus on the clinical and epidemiological aspects. MATERIALS AND METHODS: A retrospective and descriptive study was performed, including all the patients with Dientamoeba fragilis infection who attended a specialized unit between January 2012 and December 2017. PCR was used to diagnose D. fragilis. Patients were treated with metronidazole or paromomycin and reviewed at four and eight weeks post-treatment. Cure was defined as the negativization of all parasitological tests, in absence of symptoms. RESULTS: 163 patients were diagnosed. The most frequent symptoms were abdominal pain (36.2%), chronic diarrhoea (12.3%), anal itching (10.4%), abdominal discomfort (9.2%), skin disease (8%), acute diarrhoea (4.3%) and vomiting (4.3%). Fifty patients were asymptomatic. Forty-two patients had eosinophilia in blood. Thirty-eight cases (23.3%) had a coinfection by Enterobius vermicularis. One hundred and seven patients received treatment, sixty-one of them with metronidazole and the rest with paromomycin. Ninety-nine patients (91%) were cured. The rate of cure was 100% in the paromomycin group versus 86.8% in the metronidazole group (p = 0.005; OR: 1.173 [1.057-1.302]). The absence of cure was associated with E. vermicularis coinfection (p = 0.014; OR: 6.167 [1.432-26.563] and with longer duration of the symptoms (175 [± 159SD]) versus 84 [± 88SD] days, p = 0.014) but multivariable analysis did not confirm these associations. CONCLUSION: Dientamoeba fragilis is an important and underestimated cause of gastrointestinal disease in both the autochthonous and immigrant or traveller population. More studies are needed to clarify its optimal treatment and the role played by E. vermicularis in its transmission and maintenance


INTRODUCCIÓN: Se describen las características clínicas y epidemiológicas de la infección por Dientamoeba fragilis. MATERIAL Y MÉTODOS: Se realizó un estudio retrospectivo y descriptivo de los pacientes diagnosticados de infección por D. fragilis en una unidad especializada entre 2012-2017. El diagnóstico de D. fragilis se realizó mediante PCR. Los pacientes fueron tratados con metronidazol o paromomicina y revisados a las 4 y 8 semanas tras tratamiento. Se consideró a los pacientes curados tras negativización microbiológica en ausencia de síntomas. RESULTADOS: Se analizaron 163 pacientes. Los síntomas más frecuentes fueron: dolor abdominal (36,2%), diarrea crónica (12,3%), prurito anal (10,4%), malestar abdominal (9,2%), síntomas cutáneos (8%), diarrea aguda y vómitos (4,3%, respectivamente). Cincuenta pacientes estaban asintomáticos. Cuarenta y dos pacientes presentaron eosinofilia. En 38 pacientes se observó coinfección por Enterobius vermicularis. Ciento siete pacientes recibieron tratamiento, 61 con metronidazol y el resto con paromomicina, con una curación del 91%. La tasa de curación fue del 100% en los pacientes tratados con paromomicina y del 86,8% en el grupo del metronidazol (p = 0,005; OR: 1,173 [1,057-1,302]). La no curación se asoció a la coinfección por E. vermicularis (p = 0,014; OR: 6,167 [1,432-26,563]) y con la mayor duración de los síntomas (175 [± 159 DE] versus 84 [± 88 DE] días; p = 0,014), pero el análisis multivariable no confirmó dichas asociaciones. CONCLUSIÓN: D. fragilis es causa importante y subestimada de enfermedad gastrointestinal tanto en poblaciones autóctonas como inmigrantes o viajeros. Se necesitan más estudios para aclarar su tratamiento óptimo y el papel desempeñado por E. vermicularis en su tratamiento


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Dientamebíase/epidemiologia , Enterobius/microbiologia , Doenças Parasitárias/microbiologia , Estudos Retrospectivos , Dientamebíase/tratamento farmacológico , Metronidazol/uso terapêutico , Coinfecção/microbiologia
5.
Enferm Infecc Microbiol Clin (Engl Ed) ; 37(5): 290-295, 2019 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30274823

RESUMO

INTRODUCTION: The characteristics of D. fragilis infection are described, with special focus on the clinical and epidemiological aspects. MATERIALS AND METHODS: A retrospective and descriptive study was performed, including all the patients with Dientamoeba fragilis infection who attended a specialized unit between January 2012 and December 2017. PCR was used to diagnose D. fragilis. Patients were treated with metronidazole or paromomycin and reviewed at four and eight weeks post-treatment. Cure was defined as the negativization of all parasitological tests, in absence of symptoms. RESULTS: 163 patients were diagnosed. The most frequent symptoms were abdominal pain (36.2%), chronic diarrhoea (12.3%), anal itching (10.4%), abdominal discomfort (9.2%), skin disease (8%), acute diarrhoea (4.3%) and vomiting (4.3%). Fifty patients were asymptomatic. Forty-two patients had eosinophilia in blood. Thirty-eight cases (23.3%) had a coinfection by Enterobius vermicularis. One hundred and seven patients received treatment, sixty-one of them with metronidazole and the rest with paromomycin. Ninety-nine patients (91%) were cured. The rate of cure was 100% in the paromomycin group versus 86.8% in the metronidazole group (p=0.005; OR: 1.173 [1.057-1.302]). The absence of cure was associated with E. vermicularis coinfection (p=0.014; OR: 6.167 [1.432-26.563] and with longer duration of the symptoms (175 [±159SD]) versus 84 [±88SD] days, p=0.014) but multivariable analysis did not confirm these associations. CONCLUSION: Dientamoeba fragilis is an important and underestimated cause of gastrointestinal disease in both the autochthonous and immigrant or traveller population. More studies are needed to clarify its optimal treatment and the role played by E. vermicularis in its transmission and maintenance.


Assuntos
Dientamebíase , Adulto , Antiprotozoários/uso terapêutico , Dientamebíase/diagnóstico , Dientamebíase/tratamento farmacológico , Dientamebíase/epidemiologia , Feminino , Humanos , Masculino , Metronidazol/uso terapêutico , Pessoa de Meia-Idade , Paromomicina/uso terapêutico , Estudos Retrospectivos , Adulto Jovem
6.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 36(7): 423-427, ago.-sept. 2018. graf, tab
Artigo em Inglês | IBECS | ID: ibc-176723

RESUMO

INTRODUCTION: The results of a study on the household contacts of patients with D. fragilis infection are presented. METHODS: A prospective, descriptive study was carried out on all Dientamoeba fragilis-infected patients treated at the Tropical Medicine Unit of Hospital Universitario Central de Asturias between 2012- 2017 and their household contacts. Three stool samples per patient and three stool samples from each of their household contacts were concentrated and analysed. Polymerase chain reaction (PCR) was used to detect the presence of D. fragilis in all stool samples. Co-infection with E. vermicularis was studied in both groups. Patients and contacts who failed to deliver one or more samples for diagnosis and patients without household contacts were excluded. RESULTS: 44 Patients infected with D. fragilis, as well as their 97 household contacts were enrolled. 50.5% of household contacts had a positive PCR for D. fragilis. 20 were also coinfected with E. vermicularis. The presence of infection was significantly more frequent in patients with children (34/15 versus 24/24; p= 0.064; OR: 2.267 [0.988-5.199]), E. vermicularis infection in the children being 20/29 versus 0/48 (p = 0.0001), and in another family member being 29/20 versus 15/33 (p = 0.008; OR: 3.190 [1.384-7.352]). CONCLUSIONS: The prevalence of D. fragilis infection in household contacts was high. It was associated with the presence of children in the family nucleus and coinfection with E. vermicularis irrespective of gender, age, rural area or contact with animals


INTRODUCCIÓN: Los informes de sensibilidad acumulada son una herramienta valiosa para guiar el tratamiento empírico de infecciones urinarias, sobre todo en el contexto actual de crecientes tasas de resistencia. Nuestro objetivo es analizar la sensibilidad antimicrobiana de bacterias aisladas de urocultivos de pacientes pediátricos durante un período de 5 años. MÉTODOS: Estudio retrospectivo de los urocultivos del período 2011-2015. La identificación y estudios de sensibilidad se realizaron con el sistema Vitek-2 (BioMérieux(R)) y se interpretaron según los criterios de EUCAST. Se analizaron los datos de sensibilidad antimicrobiana según sexo y tramos de edad (neonatos, 1 mes-5 años, 5-15 años) y se compararon con los datos de mayores de 15 años. RESULTADOS: En el período analizado se procesaron 17.164 urocultivos de 7.924 pacientes menores de 16 años. Los porcentajes de sensibilidad en estos pacientes fueron: ampicilina 36,3%; amoxicilina/clavulánico 75,3%; cefuroxima 83,2%; cotrimoxazol 68,9%; ciprofloxacino 85,3%; fosfomicina 85,5%; nitrofurantoína 84,4%, y cefalosporinas de tercera generación 89-91%. Aminoglucósidos (>92%) y carbapenemas (95%) mantienen las mayores tasas de sensibilidad. La prevalencia de aislamientos productores de BLEE fue significativamente menor en niños menores de 16 años (1,5% vs. 4,1%). En menores de 16 años, los aislamientos de Escherichia coli procedentes de mujeres fueron significativamente (p < 0,0001) más sensibles a ampicilina (41% vs. 30%) y amoxicilina-clavulánico (82% vs. 72%) que en varones. CONCLUSIONES: La elaboración de informes de sensibilidad acumulados desglosados por edad o sexo permite detectar importantes diferencias. En nuestra área, cefuroxima puede considerarse como primera opción de tratamiento empírico en pacientes pediátricos


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Bacteroides fragilis/genética , Infecções por Bacteroides/diagnóstico , Infecções por Bacteroides/epidemiologia , Busca de Comunicante , Infecções por Bacteroides/transmissão , Reação em Cadeia da Polimerase , Estudos Prospectivos , Prevalência
7.
Anal Chem ; 90(13): 7989-7996, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29863846

RESUMO

In this work, we report for the first time the accumulation activity by energized rat heart mitochondria and the ionic transfer process at a liquid-liquid interface of a novel mitochondria-targeted antioxidant, named as AntiOxCIN4, which is structurally based on a hydroxycinnamic acid. Lipophilicity studies conducted at the water/1,6-dichlorohexane (DCH) interface allowed the building up of an ionic partition diagram of AntiOxCIN4 in accordance with the electrochemical data obtained. The partition coefficients of both positively charged (-2.3) and zwitterionic (0.2) forms of the antioxidant were determined. This study contributed to gaining an insight about the ability of the synthesized antioxidants to cross biomembrane barriers by using an interface between two immiscible electrolyte solutions (ITIES) as a model system.


Assuntos
Antioxidantes/química , Antioxidantes/metabolismo , Cicloexanos/química , Mitocôndrias/metabolismo , Água/química , Animais , Eletroquímica , Concentração de Íons de Hidrogênio , Ratos , Soluções
8.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29078992

RESUMO

INTRODUCTION: The results of a study on the household contacts of patients with D. fragilis infection are presented. METHODS: A prospective, descriptive study was carried out on all Dientamoeba fragilis-infected patients treated at the Tropical Medicine Unit of Hospital Universitario Central de Asturias between 2012- 2017 and their household contacts. Three stool samples per patient and three stool samples from each of their household contacts were concentrated and analysed. Polymerase chain reaction (PCR) was used to detect the presence of D. fragilis in all stool samples. Co-infection with E. vermicularis was studied in both groups. Patients and contacts who failed to deliver one or more samples for diagnosis and patients without household contacts were excluded. RESULTS: 44 Patients infected with D. fragilis, as well as their 97 household contacts were enrolled. 50.5% of household contacts had a positive PCR for D. fragilis. 20 were also coinfected with E. vermicularis. The presence of infection was significantly more frequent in patients with children (34/15 versus 24/24; p= 0.064; OR: 2.267 [0.988-5.199]), E. vermicularis infection in the children being 20/29 versus 0/48 (p=0.0001), and in another family member being 29/20 versus 15/33 (p=0.008; OR: 3.190 [1.384-7.352]). CONCLUSIONS: The prevalence of D. fragilis infection in household contacts was high. It was associated with the presence of children in the family nucleus and coinfection with E. vermicularis irrespective of gender, age, rural area or contact with animals.


Assuntos
Dientamoeba/isolamento & purificação , Dientamebíase/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/parasitologia , Busca de Comunicante , Dientamebíase/parasitologia , Dientamebíase/transmissão , Disenteria Amebiana/epidemiologia , Entamoeba/isolamento & purificação , Características da Família , Fezes/parasitologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Espanha/epidemiologia , Adulto Jovem
9.
J Med Chem ; 60(16): 7084-7098, 2017 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-28745898

RESUMO

Targeting mitochondrial oxidative stress is an effective therapeutic strategy. In this context, a rational design of mitochondriotropic antioxidants (compounds 22-27) based on a dietary antioxidant (caffeic acid) was performed. Jointly named as AntiOxCINs, these molecules take advantage of the known ability of the triphenylphosphonium cation to target active molecules to mitochondria. The study was guided by structure-activity-toxicity-property relationships, and we demonstrate in this work that the novel AntiOxCINs act as mitochondriotropic antioxidants. In general, AntiOxCINs derivatives prevented lipid peroxidation and acted as inhibitors of the mitochondrial permeability transition pore. AntiOxCINs toxicity profile was found to be dependent on the structural modifications performed on the dietary antioxidant. On the basis of mitochondrial and cytotoxicity/antioxidant cellular data, compound 25 emerged as a potential candidate for the development of a drug candidate with therapeutic application in mitochondrial oxidative stress-related diseases. Compound 25 increased GSH intracellular levels and showed no toxicity on mitochondrial morphology and function.


Assuntos
Antioxidantes/farmacologia , Ácidos Cafeicos/farmacologia , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/síntese química , Antioxidantes/toxicidade , Ácidos Cafeicos/síntese química , Ácidos Cafeicos/toxicidade , Ácido Glutâmico/metabolismo , Glutationa/metabolismo , Células Hep G2 , Humanos , Ferro/química , Quelantes de Ferro/síntese química , Quelantes de Ferro/farmacologia , Quelantes de Ferro/toxicidade , Peroxidação de Lipídeos/efeitos dos fármacos , Malatos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/antagonistas & inibidores , Poro de Transição de Permeabilidade Mitocondrial , Ratos , Ácido Succínico/metabolismo
10.
Sci Rep ; 7(1): 6842, 2017 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-28754950

RESUMO

Oxidative stress and mitochondrial dysfunction have been associated with metabolic and age-related diseases. Thus, the prevention of mitochondrial oxidative damage is nowadays a recognized pharmacological strategy to delay disease progression. Epidemiological studies suggested an association between the consumption of polyphenol-rich diet and the prevention of different pathologies, including diseases with a mitochondrial etiology. The development of mitochondrial-targeted antioxidants based on dietary antioxidants may decrease mitochondrial oxidative damage. Herein, we report the design and synthesis of two new mitochondriotropic antioxidants based on hydroxybenzoic acids (AntiOxBENs). The results obtained showed that the novel antioxidants are accumulated inside rat liver mitochondria driven by the organelle transmembrane electric potential and prevented lipid peroxidation, exhibiting low toxicity. Some of the observed effects on mitochondrial bioenergetics resulted from an increase of proton leakage through the mitochondrial inner membrane. The new derivatives present a higher lipophilicity than the parent compounds (protocatechuic and gallic acids) and similar antioxidant and iron chelating properties. AntiOxBENs are valid mitochondriotropic antioxidant prototypes, which can be optimized and used in a next future as drug candidates to prevent or slow mitochondrial oxidative stress associated to several pathologies.


Assuntos
Antioxidantes/farmacologia , Hidroxibenzoatos/farmacologia , Quelantes de Ferro/farmacologia , Mitocôndrias Hepáticas/efeitos dos fármacos , Animais , Antioxidantes/administração & dosagem , Antioxidantes/síntese química , Linhagem Celular , Respiração Celular , Suplementos Nutricionais , Células Hep G2 , Humanos , Hidroxibenzoatos/administração & dosagem , Hidroxibenzoatos/síntese química , Quelantes de Ferro/administração & dosagem , Quelantes de Ferro/síntese química , Masculino , Mitocôndrias Hepáticas/metabolismo , Ratos , Ratos Wistar
11.
Talanta ; 160: 653-679, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27591662

RESUMO

This work describes the state of the art of electrochemical devices for the detection of an important class of neurotransmitters: the catecholamines. This class of biogenic amines includes dopamine, noradrenaline (also called norepinephrine) and adrenaline (also called epinephrine). Researchers have focused on the role of catecholamine molecules within the human body because they are involved in many important biological functions and are commonly associated with several diseases, such as Alzheimer's and Parkinson. Furthermore, the release of catecholamines as a consequence of induced stimulus is an important indicator of reward-related behaviors, such as food, drink, sex and drug addiction. Thus, the development of simple, fast and sensitive electroanalytical methodologies for the determination of catecholamines is currently needed in clinical and biomedical fields, as they have the potential to serve as clinically relevant biomarkers for specific disease states or to monitor treatment efficacy. Currently, three main strategies have used by researchers to detect catecholamine molecules, namely: the use electrochemical materials in combination with, for example, HPLC or FIA, the incorporation of new materials/layers on the sensor surfaces (Tables 1-7) and in vivo detection, manly by using FSCV at CFMEs (Section 10). The developed methodologies were able not only to accurately detect catecholamines at relevant concentration levels, but to do so in the presence of co-existing interferences in samples detected (ascorbate, for example). This review examines the progress made in electrochemical sensors for the selective detection of catecholamines in the last 15 years, with special focus on highly innovative features introduced by nanotechnology. As the literature in rather extensive, we try to simplify this work by summarizing and grouping electrochemical sensors according to the manner their substrates were chemically modified. We also discuss the current and future of electrochemical sensors for catecholamines in terms of the analytical performance of the devices and emerging applications.


Assuntos
Técnicas Biossensoriais , Catecolaminas/análise , Neurotransmissores/análise , Animais , Técnicas Eletroquímicas , Humanos , Nanotecnologia
12.
Nutr Res ; 36(1): 9-15, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26773776

RESUMO

Paraoxonase 1 (PON1) is an enzyme that prevents the peroxidation of lipoprotein and cell membranes. Our hypothesis is that the effect of the PON1 T(-107)C polymorphism on serum PON1 activity in healthy adult women is dependent on their fatty acid intake profile. This study included women (n = 39) who completed a food frequency questionnaire. Fatty acid intake was estimated based on the interview and a nutrient reference table. Blood samples were collected for genotyping and to measure serum PON1 activity. Serum PON1 activity was different among genotypes and was higher for women of the CC genotype (P < .001). Women in the study were categorized in 2 groups according to the median nutrient intake. Overall, there was a difference (P < .05) in serum PON1 activity between the CC and TT genotypes in women ingesting either above or below the median total fat, saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids, omega 3 (n-3) and omega 6 (n-6; P < .05). However, genotype effects on serum PON1 activity were not observed in women ingesting below the median (15:1) ratio of n-6/n-3 (P > .05) but were observed in women ingesting above the ratio of n-6/n-3 (P < .05). This is partly because women of the CC genotype had decreased PON1 activity when ingesting a lower ratio of n-6/n-3 diet (P < .05), while women of the TT genotype had increased PON1 activity (P < .05). In conclusion, the overall presence of the C allele was associated with increased serum PON1 activity, although a diet with high saturated fatty acid or a low ratio of n-6/n-3 reduced PON1 activity in women with the CC genotype.


Assuntos
Arildialquilfosfatase/genética , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-6/administração & dosagem , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Adolescente , Adulto , Arildialquilfosfatase/sangue , Arildialquilfosfatase/metabolismo , Brasil , Estudos Transversais , Deficiências Nutricionais/sangue , Deficiências Nutricionais/enzimologia , Deficiências Nutricionais/etiologia , Deficiências Nutricionais/genética , Ácidos Graxos Essenciais/deficiência , Ácidos Graxos Ômega-3/efeitos adversos , Ácidos Graxos Ômega-6/efeitos adversos , Ácidos Graxos Ômega-6/deficiência , Feminino , Estudos de Associação Genética , Hospitais Universitários , Humanos , Peroxidação de Lipídeos , Pessoa de Meia-Idade , Inquéritos Nutricionais , Adulto Jovem
13.
Anal Chem ; 85(3): 1582-90, 2013 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-23301839

RESUMO

In this work, the ion transfer mechanism of the anticancer drug daunorubicin (DNR) at a liquid/liquid interface has been studied for the first time. This study was carried out using electrochemical techniques, namely cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The lipophilicity of DNR was investigated at the water/1,6-dichlorohexane (DCH) interface, and the results obtained were presented in the form of an ionic partition diagram. The partition coefficients of both neutral and ionic forms of the drug were determined. The analytical parameter for the detection of DNR was also investigated in this work. An electrochemical DNR sensor is proposed by means of simple ion transfer at the water/DCH interface, using DPV as the quantification technique. Experimental conditions for the analytical determination of DNR were established, and a detection limit of 0.80 µM was obtained.


Assuntos
Antibióticos Antineoplásicos/química , Daunorrubicina/química , Técnicas Eletroquímicas/métodos , Óleos/química , Água/química , Antibióticos Antineoplásicos/metabolismo , Daunorrubicina/metabolismo , Humanos , Óleos/metabolismo , Água/metabolismo
14.
Talanta ; 88: 54-60, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22265469

RESUMO

In this work, ion transfer and facilitated ion transfer of ammonium ion by a lipophilic cyclodextrin is investigated at the water/1,6-dichlorohexane micro-interface, using electrochemical approaches (cyclic voltammetry, differential pulse voltammetry and square wave voltammetry). The association constant has been obtained for the complex between ammonium ion and the cyclodextrin. Experimental conditions for the analytical determination of ammonium ion were established and a detection limit of 0.12 µM was obtained. The amperometric sensor gave a current response proportional to the ammonium ion concentration in the range from 4.2 to 66 µM.


Assuntos
Cicloexanos/química , Potenciometria/métodos , Compostos de Amônio Quaternário/análise , Água/química , Cátions , Ciclodextrinas/química , Limite de Detecção
15.
J Colloid Interface Sci ; 358(2): 626-34, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21481406

RESUMO

Thin films composed of oleylamine (OLA) and double-stranded deoxyribonucleic acid (dsDNA from Salmon testes) have been successfully constructed on polycrystalline Au surfaces using the electrostatic adsorption and self-assembly (SA) technique. The formation of the Au/OLA/dsDNA films was followed step-by-step by Quartz Crystal Microbalance with energy dissipation (QCM-D), Atomic Force Microscopy (AFM), and electrochemical techniques such as Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). The use of these techniques allowed the characterization and the follow up of the successful construction of the OLA/dsDNA composite film. The main advantages of the proposed methodology are the simplicity of the modification procedure, the stability of the dsDNA self-assembled film, and the potential employment of the dsDNA modified gold electrodes to study the interactions of DNA with target molecules.


Assuntos
Aminas/química , DNA/química , Ouro/química , Adsorção , Animais , Eletrodos , Métodos , Salmão , Propriedades de Superfície
16.
Phys Chem Chem Phys ; 12(46): 15190-4, 2010 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-20882253

RESUMO

Interfaces between two immiscible electrolyte solutions are recognized as a simplified model for biological systems and they can be of great relevance to the characterization of biomolecules and their role in biological systems. In this work, ion transfer and facilitated ion transfer of protonated catecholamines (dopamine and noradrenaline) by dibenzo-18-crown-6 are investigated at the water/1,6-dichlorohexane interface. The formation constant of the complex between both dopamine and noradrenaline with dibenzo-18-crown-6 was evaluated and the experimental conditions for the analytical determination of those catecholamines are established. These results can improve the understanding of the pharmacodynamics of the catecholamines, and contribute to the study of their interaction with biological membranes. Furthermore it can be used to develop an alternative method for the determination of neural signal transmission catecholamines.


Assuntos
Cicloexanos/química , Dopamina/análise , Norepinefrina/análise , Dopamina/química , Eletroquímica , Estrutura Molecular , Norepinefrina/química , Água/química
17.
Rev. bras. cancerol ; 37(1/4): 41-4, jan.-dez. 1991. ilus, tab
Artigo em Português | LILACS | ID: lil-157806

RESUMO

Foi realizado um estudo imuno-histoquímico para verificar a expressäo de enolase neurônio-específica (NSE), alfa 1-antitripsina (AAT) e alfa 1-antiquimotripsina (AAQT) em tumores malignos de células germinativas do ovário. As reaçöes imuno-histoquímicas foram realizadas em tecidos previamente fixados em formol e embebidos em parafina de sete disgerminomas, três tumores do seio endodérmico, três teratomas imaturos e um oriocarcinoma. Todos os tumores, exceto o coriocarcinoma, expressaram NSE. As reaçös com anticorpos anti-AAT e AAQT foram positivas em todos os tipos histológicos dos tumores. Estes dados sugerem que NSE, AAT ou AAQT podem ser mais um marcador para os tumores de células germinativas do ovário.


Assuntos
Humanos , alfa 1-Antiquimotripsina , alfa 1-Antitripsina , Coriocarcinoma/metabolismo , Disgerminoma/metabolismo , Germinoma/metabolismo , Biomarcadores Tumorais , Neoplasias Ovarianas/metabolismo , Fosfopiruvato Hidratase , Teratoma/metabolismo , Tumor do Seio Endodérmico/metabolismo , Imuno-Histoquímica
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