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1.
Eur Rev Med Pharmacol Sci ; 25(9): 3432-3439, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34002816

RESUMO

OBJECTIVE: Adenomyosis is the consequence of the myometrial invasion by endometrial glands and stroma. Transvaginal ultrasonography plays a decisive role in the diagnosis and monitoring of this pathology. Our study aims to evaluate the efficacy of LNG-IUS (Levonorgestrel Releasing Intrauterine System) as medical therapy. We analyzed both clinical symptoms and ultrasonographic aspects of menometrorrhagia and dysmenorrhea in patients with adenomyosis and the control group. PATIENTS AND METHODS: A prospective cohort study was carried out on 28 patients suffering from symptomatic adenomyosis treated with LNG-IUS. Adenomyosis was diagnosed through transvaginal ultrasonography by an expert sonographer. A control group of 27 symptomatic patients (menorrhagia and dysmenorrhea) without a transvaginal ultrasonographic diagnosis of adenomyosis was treated in the same way. The two cohorts were compared to the efficacy of LNG-IUS on menorrhagia and dysmenorrhea.  Patients are evaluated at the time of LNG-IUS insertion and six months after for: increased uterine volume, globulous uterine morphology, uterine symmetry, alterations in the junctional zone, heterogeneous myometrial texture, presence of myometrial cysts, hyperechogenic lines crossing the myometrium, adenomyomas, menstrual blood loss and dysmenorrhea. RESULTS: After six months, the uterine volume decreased significantly in both cohorts (p=0.005; p=0.005). Furthermore, uterine symmetry, visibility of the junctional zone, heterogeneity of myometrial texture, presence of myometrial cysts, hyperechogenic lines and adenomyomas improved in patients affected by adenomyosis (p>0.001; p>0.001; p>0.001; p=0.014; p=0.025; p=0.014). The blood loss decreased significantly in both the cohorts (p<0.001) and particularly in adenomyotic patients. Pain relief was observed in all the patients (p<0.001). CONCLUSIONS: LNG-IUS can be considered an effective treatment for managing symptoms and improving uterine morphology.


Assuntos
Adenomiose/tratamento farmacológico , Dismenorreia/tratamento farmacológico , Dispositivos Intrauterinos Medicados , Levanogestrel/uso terapêutico , Menorragia/tratamento farmacológico , Adenomiose/diagnóstico por imagem , Adulto , Estudos de Coortes , Dismenorreia/diagnóstico por imagem , Feminino , Humanos , Menorragia/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Prospectivos , Ultrassonografia
2.
Eur Rev Med Pharmacol Sci ; 23(14): 6035-6044, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31364105

RESUMO

OBJECTIVE: This is a pilot study to evaluate the effectiveness of the treatment with Vaginal Soft gels technology in the improvement of common signs and symptoms in postmenopausal, postpartum and with recurrent vulvovaginitis patients. These conditions may cause the onset of Vulvovaginal Atrophy (VVA) with effects on sexual activity, self-confidence and daily activities. The main symptoms are itching, irritation and dryness. Many therapies have been evaluated and almost all those without hormonal component have shown poor results. PATIENTS AND METHODS: Women diagnosed with severe VVA from January to September 2018 were recruited. The study groups were composed of 25 postmenopausal women, 30 post-partum women and 30 women with recurrent vulvovaginitis. For each group, patients were randomized 1:1 among those who carried out the experimental treatment and those that did not perform it. The efficacy of treatment was evaluated with a clinical visit in which Vaginal Health Index (VHI) was estimated. The symptomatology was determined through the questionnaire Female Sexual Function Index (FSFI). RESULTS: A significant improvement has been shown with regard to the sexual function (orgasm, lubrification, pain) in patients who performed the treatment. A significant increase in VHI has been evaluated in postmenopausal patients (4 months p=0.054, 6 months p=0.005) and in recurrent vulvovaginitis but not in post-partum patients (4 months p=0.681, 6 months p=0.109). An improvement of lubrication, satisfaction, orgasm, pain, as well as dyspareunia, was observed in the three study groups. CONCLUSIONS: In this pilot study the treatment with soft gels seems to be effective in improving sexual health and atrophy being a treatment available for all types of patients thanks to the absence of systemic and local side effects. It is an excellent alternative especially for patients who cannot use hormones. These findings must be confirmed by larger and randomized further studies.


Assuntos
Vaginite Atrófica/prevenção & controle , Cremes, Espumas e Géis Vaginais/administração & dosagem , Vulvovaginite/tratamento farmacológico , Vulvovaginite/psicologia , Adulto , Vaginite Atrófica/psicologia , Desenho de Equipamento , Feminino , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Pós-Menopausa , Período Pós-Parto , Distribuição Aleatória , Resultado do Tratamento , Cremes, Espumas e Géis Vaginais/química , Vulvovaginite/complicações , Adulto Jovem
3.
Anal Bioanal Chem ; 411(9): 1915-1926, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30610251

RESUMO

Deoxynivalenol (DON) is a toxic secondary metabolite produced by several species of Fusarium fungi, which can be predominantly found in agricultural crops such as wheat. In livestock, deoxynivalenol-contaminated grain can produce vomiting, feed refusal, weight loss, and diarrhea. This paper reports an electrochemical immunosensor for the detection of residual DON mycotoxin in food samples. The device uses electrochemical nanoprobes (CdSNP-AbDON) and antigen biofunctionalized magnetic µ-particles (DON-BSAMP) to detect the mycotoxin. CdSNP-AbDON are prepared by labelling the DON-specific antibodies with CdS nanoparticles (CdSNPs). Nanoparticle size and CdSNP-AbDON conjugation ratio are characterized using TEM images. The metal ions released by the CdSNP are reduced at the working electrode and read by anodic stripping voltammetry. DON can be detected in PBST buffer with an IC50 of 6.74 ± 0.19 µg L-1. The high detectability of the immunosensor developed allows detection of DON residues in 50-fold diluted wheat extracts. The limit of detection (LOD, IC90) accomplished in wheat is of 342.4 µg kg-1, which is below the maximum residue limit (MRL, 1750 µg kg-1 for unprocessed durum wheat, 750 µg kg-1 for cereals intended for direct human consumption) established by the EU for this mycotoxin. The working range is in the interval between 610 and 6210 µg kg-1. The performance of the immunosensor was compared with the ELISA assay. DON naturally contaminated wheat samples were analyzed with the immunosensor, showing acceptable recoveries. Graphical abstract.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Contaminação de Alimentos/análise , Sondas Moleculares , Micotoxinas/análise , Nanopartículas , Tricotecenos/análise , Triticum/química , Limite de Detecção , Microscopia Eletrônica de Transmissão , Reprodutibilidade dos Testes
4.
Food Chem ; 178: 156-63, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25704696

RESUMO

A rapid high-throughput immunochemical screening (HtiS) procedure for the analysis of the sulfonamide (SA)-sugar conjugated fraction of antibiotic contaminated honey samples has been developed. Studies performed with this matrix have indicated that sulfonamide antibiotics are conjugated to sugars rapidly and quantitatively, providing samples with very low SA immunoreactivity. Therefore, sulfonamides must be first released before the analysis, and for this purpose, a simple and fast sample preparation procedure has been established consisting of hydrolyzing the sample for 5 min, adjusting the pH and buffering the sample prior to the immunochemical analysis. Under these conditions, honey samples could be directly analyzed without any additional sample treatment, other than dilution. Recovery values of the whole analytical procedure were greater than 85%. The analysis of the same samples without the hydrolysis provided recovery values below 5%. Selectivity studies performed in hydrolyzed honey samples revealed that nine relevant sulfonamide antibiotics can be detected with limit of detection (LOD) values below the action limits established by some EU countries (Belgium, 20 µg kg(-1), United Kingdom or Switzerland, 50 µg kg(-1)).


Assuntos
Antibacterianos/análise , Carboidratos/análise , Contaminação de Alimentos/análise , Mel/análise , Sulfonamidas/análise , Carboidratos/química , Ensaio de Imunoadsorção Enzimática , Hidrólise , Sulfonamidas/química
5.
Anal Bioanal Chem ; 405(24): 7885-95, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23907682

RESUMO

A new electrochemical magnetoimmunosensor (EMIS) has been developed for the screening of residues of sulfonamide antimicrobials in honey samples. The immunosensor is able to detect up to ten different sulfonamide congeners at levels below the action points established in some European countries (25 µg kg(-1)) after a hydrolysis step in which the sulfonamides are released from the corresponding conjugates formed in samples of this type. In spite of the complexity of the sample after the hydrolysis procedure, the EMIS could perform quantitative measurements, directly in these samples, without any additional sample cleanup or extraction step. For example, sulfapyridine, used as a reference, can be detected in hydrolyzed honey with a limit of detection (IC90) of 0.1 ± 0.03 µg kg(-1). Considering that the use of antibiotics for bee treatment is prohibited in the European Union, the immunosensor presented here could be an excellent screening tool. Moreover, several samples can be processed in parallel, which facilitates the analysis, reducing the necessity to use more costly confirmatory methods for just screening. As a proof of concept, a set of blind honey samples (spiked and incurred) were analyzed and the results were compared with those obtained by high-performance liquid chromatography-tandem mass spectrometry, demonstrating the potential of the EMIS as a screening tool.


Assuntos
Resíduos de Drogas/análise , Eletroquímica/instrumentação , Tecnologia de Alimentos/instrumentação , Tecnologia de Alimentos/métodos , Mel/análise , Magnetismo , Sulfonamidas/análise , Animais , Abelhas , Equipamentos e Provisões
6.
Biosens Bioelectron ; 43: 211-7, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23313703

RESUMO

A new electrochemical immunosensor has been developed to detect sulfonamide antibiotic residues in food samples. The immunosensor presented uses immunoreagents specifically developed for the broad recognition of the sulfonamide antibiotic family, a graphite composite electrode (GEC), biofunctionalized magnetic µ-particles and electrochemical nanoprobes prepared by labeling the specific antibodies with CdS nanoparticles (CdSNP). After the immunochemical reaction, the CdSNP are dissolved and the metal ions released are reduced at the electrode and read as in the form of current or charge signal, by the well-known anodic stripping technique. Due to the amplification effect on the amperometric/coulombimetric signal produced by the CdSNP, a high detectability can be reached. Thus, sulfapyridine (SPY), one of the most widely used sulfonamide congeners, can be detected in buffer with an IC50current of 0.20±0.25µgL(-1). The immunosensor has been applied to the analysis of residues of this antibiotic in honey samples. Due to the reported formation of sulfonamide-sugar conjugates in this type of matrix, honey samples are first hydrolyzed in acidic media. The use of magnetic particles minimizes the matrix effect allowing to reach a detectability (LOD, limit of detection) of 0.11µgkg(-1) (current measurements), far below the limits established in some countries for these types of residues in honey samples. Due to the use of magnetic racks, multiple samples can be run simultaneously. The whole analysis process can be performed in around 22min.


Assuntos
Antibacterianos/análise , Compostos de Cádmio/química , Condutometria/instrumentação , Análise de Alimentos/instrumentação , Contaminação de Alimentos/análise , Mel/análise , Imunoensaio/instrumentação , Compostos de Selênio/química , Técnicas Biossensoriais/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Eletricidade Estática
7.
J Chromatogr A ; 1218(29): 4727-37, 2011 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-21683367

RESUMO

Toremifene is a selective estrogen receptor modulator included in the list of prohibited substances in sport by the World Anti-doping Agency. The aim of the present study was to investigate toremifene metabolism in humans in order to elucidate the structures of the most abundant urinary metabolites and to define the best marker to detect toremifene administration through the analysis of urine samples. Toremifene (Fareston) was administered to healthy volunteers and the urine samples were subjected to different preparation methods to detect free metabolites as well as metabolites conjugated with glucuronic acid or sulphate. Urinary extracts were analyzed by LC-MS/MS with triple quadrupole analyzer using selected reaction monitoring mode. Transitions for potential metabolites were selected by using the theoretical [M+H](+) as precursor ion and m/z 72 or m/z 58 as product ions for N,N-dimethyl and N-desmethyl metabolites, respectively. Toremifene and 20 metabolites were detected in excretion study samples, excreted free or conjugated with glucuronic acid or sulphate. Structures for most abundant phase I metabolites were proposed using accurate mass measurements performed by QTOF MS, based on fragmentation pattern observed for those metabolites available as reference standards. Several metabolic pathways including mono- and di-hydroxylation, N-desmethylation, hydroxymethylation, oxidation, dehalogenation and combinations were proposed. All metabolites were detected up to one month after toremifene administration; the most abundant metabolites were detected in the free fraction and they were metabolites resulting from dehalogenation. Several of the metabolites elucidated in this work have not been reported until now in the scientific literature.


Assuntos
Dopagem Esportivo , Espectrometria de Massas em Tandem/métodos , Toremifeno/urina , Cromatografia Líquida , Ácido Glucurônico , Humanos , Redes e Vias Metabólicas , Moduladores Seletivos de Receptor Estrogênico/metabolismo , Moduladores Seletivos de Receptor Estrogênico/urina , Toremifeno/metabolismo
8.
Gynecol Obstet Invest ; 71(3): 145-50, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21150154

RESUMO

BACKGROUND/AIMS: This study aims to evaluate the pelvic floor (PF) tension response during simulated increased intra-abdominal pressure (IAP) and the vaginal biomechanical properties. METHODS: A 3-dimensional computational finite element model for PF was developed based on magnetic resonance imaging from a nulliparous healthy volunteer. The model was used to simulate an IAP of 90 cm H(2)O and to evaluate the PF stresses in the longitudinal and transversal axes. The vaginal samples were obtained from 15 non-prolapsed female cadavers. A uniaxial tensile test to obtain stiffness and maximum stress of vaginal tissue in the longitudinal and transversal axes was performed. RESULTS: The simulated IAP was associated with a similar PF stress state in the longitudinal and transversal axes. The stiffness and maximum stress in vaginal tissues presented a great variability between subjects. There was no difference in the vaginal tissue elasticity (6.2 ± 1.5 vs. 5.4 ± 1.1 MPa; p = 0.592) and maximum stress (2.3 ± 0.5 vs. 2.6 ± 0.9 MPa; p = 0.692) regarding the measurements in the longitudinal and transversal axes. CONCLUSION: The isotropic biomechanical behavior of vagina is in agreement with the PF stress state response during increased IAP.


Assuntos
Abdome/fisiologia , Pressão , Vagina/fisiologia , Adolescente , Adulto , Fenômenos Biomecânicos/fisiologia , Simulação por Computador , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Modelos Biológicos , Diafragma da Pelve/fisiologia , Estresse Mecânico , Resistência à Tração , Adulto Jovem
10.
Anal Chim Acta ; 672(1-2): 3-8, 2010 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-20579481

RESUMO

A new rapid method which allows simultaneous one step detection of two analytes of different nature (2,4,6,-trichlorophenol (TCP) and ochratoxin A (OTA)) in red wine was developed. It was based on a column test with three separate immunolayers: two test layers and one control layer. Each layer consisted of sepharose gel with immobilized anti-OTA (OTA test layer), anti-TCP (TCP test layer) or anti-HRP (control layer) antibodies. Analytes bind to the antibodies in the corresponding test layer while sample flows through the column. Then a mixture of OTA-HRP and TCP-HRP in appropriate dilutions was used, followed by the application of chromogenic substrate. Colour development of the test layer occurred when the corresponding analyte was absent in the sample. HRP-conjugates bound to anti-HRP antibody in the control layer independently of presence or absence of analytes and a blue colour developed in the control layer. Cut-off values for both analytes were 2 microg L(-1). The described method was applied to the simultaneous detection of TCP and OTA in wine samples. To screen the analytes in red wine samples, clean-up columns were used for sample pre-treatment in combination with the test column. Results were confirmed by chromatographic methods.


Assuntos
Clorofenóis/análise , Ocratoxinas/análise , Vinho/análise , Anticorpos/imunologia , Clorofenóis/imunologia , Géis/química , Imunoensaio , Ocratoxinas/imunologia
11.
Nefrologia ; 30(1): 119-26, 2010.
Artigo em Espanhol | MEDLINE | ID: mdl-20098474

RESUMO

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in patients with chronic kidney disease (CKD). Cardiovascular risk assessment in this population is hampered by the failure of traditional risk factors to fully account for the elevated CVD risk, mainly due to the reverse epidemiology effect, and the presence of risk factors specifically related to uremia. Hereby, we present the protocol of a prospective study aimed to assess the predictive value of imaging techniques and biomarkers for CVD in patients with CKD. METHODS: From November 2009, 2.661 asymptomatic adult patients with stages 3-5D CKD will be recruited from nephrology services and dialysis units throughout Spain. Eight hundred forty-three participants without CKD (control group) will be also recruited. During the follow-up, CVD events and mortality will be recorded from all CKD patients. One trained itinerant team will carry out a carotid ultrasound to assess intima-media thickness and presence of plaques. A composite atherosclerosis score will be constructed based on carotid ultrasound data and ankle-brachial index. Presence and type of calcifications will be assessed in carotid, femoral and brachial arteries, and in cardiac valves, by ultrasound. Finally, blood samples will be collected from all participants to study biomarkers. DISCUSSION: The NEFRONA study will allow us to examine the usefulness of imaging techniques and biomarkers to assess atherosclerosis development and their predictive value in a Spanish population with CKD.


Assuntos
Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/etiologia , Nefropatias/complicações , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Doença Crônica , Feminino , Humanos , Nefropatias/sangue , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Valor Preditivo dos Testes , Fatores de Risco , Espanha , Ultrassonografia , Adulto Jovem
12.
Clin Nephrol ; 71(5): 475-81, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19473606

RESUMO

BACKGROUND: Chronic kidney disease is a widely recognized cardiovascular risk factor. Its detection within large populations depends upon the method used to estimate glomerular filtration. The Cockcroft and MDRD equations are widely used, although their accuracy is limited in certain cases. METHODS: The present study analyzes glomerular filtration values in 674 young, healthy subjects using five methods: Cockcroft, Cockcroft corrected for body surface, MDRD-4 Lund-Malmö and Sawyer formulas. Glomerular filtration values obtained with the first three methods were compared using ANOVA. The Spearman coefficient was calculated to estimate the correlation between MDRD-4 and Cockcroft values, and between Cockcroft values and body mass index. RESULTS: There was a slight glomerular filtration rate decrease (< 90 ml/min) seen in 394 subjects using the Cockcroft equation, and in 344 subjects using the MDRD-4 formula. The prevalence of chronic kidney disease (glomerular filtration < 60 ml/min) was seen in 3 subjects using the MDRD-4 equation and 161 subjects using the Cockcroft formula. There was significant discordance, by method, between values obtained, with 40% of the population being classified into different stages (> 90 or < 90 ml/min) depending on the formula used. In 8% of the population there was even greater discordance, because they had strictly normal renal function according to MDRD-4 (> 90 ml/min) but fell into chronic kidney disease Stage 3 (< 60 ml/min) according to the Cockcroft formula. There was poor correlation between glomerular filtration rates obtained using the Cockcroft and MDRD-4 equations, suggesting that the subjects with a glomerular filtration rate decrease detected by the two methods were not the same ones. There was correlation between body mass index and glomerular filtration rates obtained with Cockcroft, Cockcroft corrected for body surface and Sawyer formulas and not with MDRD and Lund-Malmö equations. CONCLUSIONS: There are important discrepancies between the methods used to assess renal function in healthy populations. These limitations must be taken into account when deciding on strategies for diagnosis and control of occult chronic kidney disease in the general population.


Assuntos
Taxa de Filtração Glomerular/fisiologia , Falência Renal Crônica/diagnóstico , Adulto , Feminino , Humanos , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/fisiopatologia , Masculino , Prevalência , Valores de Referência , Espanha/epidemiologia
13.
Biosens Bioelectron ; 24(7): 2057-63, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19084389

RESUMO

An immunoassay-based strategy for folic acid in vitamin-fortified milk with electrochemical detection using magneto sensors is described for the first time. Among direct and indirect competitive formats, best performance was achieved with an indirect competitive immunoassay. The immunological reaction for folic acid (FA) detection was performed, for the first time on the magnetic bead as solid support by the covalent immobilization of a protein conjugate BSA-FA on tosyl-activated magnetic bead. Further competition for the specific antibody between FA in the food sample and FA immobilized on the magnetic bead was achieved, followed by the reaction with a secondary antibody conjugated with HRP (AntiIgG-HRP). Then, the modified magnetic beads were easily captured by a magneto sensor made of graphite-epoxy composite (m-GEC) which was also used as the transducer for the electrochemical detection. The performance of the immunoassay-based strategy with electrochemical detection using magneto sensors was successfully evaluated using spiked-milk samples and compared with a novel magneto-ELISA based on optical detection. The detection limit was found to be of the order of microgl(-1) (13.1 nmoll(-1), 5.8 microgl(-1)) for skimmed milk. Commercial vitamin-fortified milk samples were also evaluated obtaining good accuracy in the results. This novel strategy offers great promise for rapid, simple, cost-effective and on-site analysis of biological and food samples.


Assuntos
Eletroquímica/instrumentação , Ácido Fólico/análise , Análise de Alimentos/instrumentação , Alimentos Fortificados/análise , Imunoensaio/instrumentação , Magnetismo/instrumentação , Leite/química , Vitaminas/química , Animais , Técnicas Biossensoriais/instrumentação , Bovinos , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Biosens Bioelectron ; 24(6): 1592-7, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18829293

RESUMO

The detection of atrazine using a novel optical immunosensing technique based on negative dielectrophoresis (n-DEP) in microfluidic channels is described. Atrazine is a toxic triazine herbicide within the most frequently used. Polystyrene microparticles (6 microm diameters) modified with bovine serum albumin conjugated with atrazine (atrazine-BSA) were manipulated and captured when subjected to intense n-DEP electric fields. Specifically, particles were trapped when AC voltages with amplitudes of 10 V(peak) and frequencies over 1 MHz were applied to the electrodes. The immunological reaction occurring on the particles for detecting atrazine is based on an indirect competitive assay using a secondary anti-mouse immunogloburin G (IgG) antibody labeled with fluorescein isothiocyanate. The microfluidic device, with three-dimensional microelectrodes, was fabricated comprising two caged areas, allowing two simultaneous measurements inside the same microfluidic channel. The performance of this n-DEP immunosensing technique was evaluated using wine samples. The immunodevice showed a limit of detection for atrazine in buffer samples of 0.11 microgL(-1) and in pre-treated wine samples of 6.8 microg L(-1); these detection limits are lower than the maximum residue level (MRL) established by the European Community for residues of this herbicide in wine (50 microg L(-1)). This methodology offers great promise for rapid, simple, cost effective, and on-site analysis of biological, foods and beverages, and environmental samples.


Assuntos
Atrazina/análise , Técnicas Biossensoriais/instrumentação , Eletroforese/instrumentação , Monitoramento Ambiental/instrumentação , Poluentes Ambientais/análise , Imunoensaio/instrumentação , Praguicidas/análise , Técnicas Biossensoriais/métodos , Eletroforese/métodos , Monitoramento Ambiental/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Imunoensaio/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Biosens Bioelectron ; 22(8): 1707-15, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-17085033

RESUMO

A novel and very sensitive electrochemical immunosensing strategy for the detection of atrazine based on affinity biocomposite transducers is presented. Firstly, the graphite-epoxy composite transducer was bulk-modified with different universal affinity biomolecules, such as avidin and Protein A. Two strategies for the immobilization of the anti-atrazine antibodies on both biocomposite transducers were evaluated: 'wet-affinity' and 'dry-assisted affinity' immobilization. Finally, the performance of a novel anti-atrazine immunocomposite bulk-modified with anti-atrazine antibodies was also evaluated. The better immobilization performance of the anti-atrazine antibodies was achieved by 'dry-assisted affinity' immobilization on Protein A (2%) graphite-epoxy biocomposite (ProtA(2%)-GEB) as a transducer. The immunological reaction for the detection of atrazine performed on the ProtA(2%)-GEB biosensors is based on a direct competitive assay using atrazine-HRP tracer as the enzymatic label. The electrochemical detection is thus achieved through a suitable substrate and a mediator for the enzyme HRP. This novel strategy was successfully evaluated using spiked orange juice samples. The detection limit for atrazine in orange juices using the competitive electrochemical immunosensing assay was found to be 6 x 10(-3) microgL-1 (0.03 nmolL-1) thus this biosensing method accomplishes by far the LODs required for the European Community directives for potable water and food samples (0.1 microgL-1). This strategy offers great promise for rapid, simple, cost effective, and on-site biosensing of biological, food, and environmental samples.


Assuntos
Atrazina/análise , Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Resíduos de Praguicidas/análise , Atrazina/imunologia , Eletroquímica
16.
Biosens Bioelectron ; 22(9-10): 2184-91, 2007 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-17126544

RESUMO

A novel electrochemical immunosensing strategy for the detection of sulfonamide antibiotics in milk based on magnetic beads is presented. Among the different strategies for immobilizing the class-specific anti-sulfonamide antibody to the magnetic beads--such as those based on the use of Protein A or carboxylate modified magnetic beads - ,the best strategy was found to be the covalent bonding on tosyl-activated magnetic beads. The immunological reaction for the detection of sulfonamide antibiotics performed on the magnetic bead is based on a direct competitive assay using a tracer with HRP peroxidase for the enzymatic labelling. After the immunochemical reactions, the modified magnetic beads can be easily captured by a magneto sensor made of graphite-epoxy composite (m-GEC), which is also used as the transducer for the electrochemical immunosensing. The electrochemical detection is thus achieved through a suitable substrate for the enzyme HRP and an electrochemical mediator. The electrochemical approach is also compared with a novel magneto-ELISA with optical detection. The performance of the electrochemical immunosensing strategy based on magnetic beads was successfully evaluated using spiked milk samples, and the detection limit was found to be 1.44 microg L(-1) (5.92 nmol L(-1)) for raw full cream milk. This strategy offers great promise for rapid, simple, cost-effective and on-site analysis of biological, food and environmental samples.


Assuntos
Antibacterianos/análise , Eletroquímica , Magnetismo , Leite/química , Sulfonamidas/análise , Animais , Antibacterianos/imunologia , Imunoensaio , Sulfonamidas/imunologia
17.
Clin Nephrol ; 66(6): 411-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17176912

RESUMO

BACKGROUND: The role of mineral metabolism in cardiovascular pathologies has been studied almost exclusively in chronic kidney disease patients. There are no studies that relate mineral metabolism to pulse pressure in healthy populations. METHODS: 692 subjects were initially selected. After applying clinical exclusion criteria, 659 subjects were recruited. Creatinine clearance was then calculated to detect subjects with occult chronic kidney disease. Statistical analysis was applied to the remaining population after excluding subjects with occult chronic kidney disease (n = 466). Pulse pressure, creatinine clearance, calcium, phosphorus, intact parathormone, 25-hydroxivitamin D3 and Bsm I genotype of the vitamin D receptor were determined. Means and frequencies were compared by ANOVA and Chi-square, respectively. Multivariate analysis was applied to the whole population and then to Caucasians, Sub-Saharans, Caucasian men and Caucasian women separately. Pulse pressure (PP) was the dependent variable, and adjustments were made for clinical and laboratory data. RESULTS: The prevalence of occult chronic kidney disease was 32%. In subjects without kidney disease, phosphorus and vitamin D were independent predictors of elevated PP in Caucasian males whereas Bsm I genotype of the vitamin D was an independent predictor of elevated PP in the Caucasian population in both genders. No covariable showed relationship with PP in Sub-Saharan subjects. CONCLUSION: Mineral metabolism influences pulse pressure in Caucasian men.


Assuntos
Pressão Sanguínea/fisiologia , Cálcio/metabolismo , Fósforo/metabolismo , Adulto , Calcifediol/metabolismo , Creatinina/sangue , Creatinina/urina , DNA/análise , Feminino , Genótipo , Humanos , Nefropatias/metabolismo , Nefropatias/fisiopatologia , Masculino , Hormônio Paratireóideo/metabolismo , Reação em Cadeia da Polimerase , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Valores de Referência , Fatores de Risco
18.
Anal Chem ; 78(6): 1780-8, 2006 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-16536412

RESUMO

A novel electrochemical immunosensing strategy for the detection of atrazine based on magnetic beads is presented. Different coupling strategies for the modification of the magnetic beads with the specific anti-atrazine antibody have been developed. The immunological reaction for the detection of atrazine performed on the magnetic bead is based on a direct competitive assay using a peroxidase (HRP) tracer as the enzymatic label. After the immunochemical reactions, the modified magnetic beads can be easily captured by a magnetosensor made of graphite-epoxy composite, which is also used as the transducer for the electrochemical immunosensing. The electrochemical detection is thus achieved through a suitable substrate and mediator for the enzyme HRP. The electrochemical approach is also compared with a novel magneto-ELISA based on optical detection. The performance of the electrochemical immunosensing strategy based on magnetic beads was successfully evaluated using spiked real orange juice samples. The detection limit for atrazine using the competitive electrochemical magnetoimmunosensing strategy with anti-atrazine-specific antibody covalent coupled with tosyl-activated magnetic beads was found to be 6 x 10(-3) microg L(-1) (0.027 nmol L(-1)). This strategy offers great promise for rapid, simple, cost-effective, and on-site analysis of biological, food, and environmental samples.


Assuntos
Atrazina/análise , Magnetismo , Resíduos de Praguicidas/análise , Anticorpos/química , Reações Antígeno-Anticorpo , Eletroquímica , Imunoensaio/instrumentação , Imunoensaio/métodos , Tamanho da Partícula , Sensibilidade e Especificidade
19.
Clin Nephrol ; 64(2): 163-6, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16114795

RESUMO

Several authors have documented beneficial effects of interferon (IFN) in chronic hepatitis C virus (HCV) infection among the dialysis population. Reports about mineral metabolism disturbances during IFN treatment are scarce, especially in dialysis patients. We report the case of a 49-year-old woman on hemodialysis with chronic HCV infection who developed significant decrease in serum calcium (Ca) and phosphorus (P) levels accompanied by relative hypoparathyroidism while being under treatment with alpha-IFN. These changes were closely related to IFN treatment, because they disappeared after INF was discontinued, reaching Ca and P levels which were similar to those of the pre-IFN period. Because IFN may induce immune disorders, several autoimmune markers were analyzed. All of them were negative or within the normal range. To further explore these mineral metabolism disturbances, a number ofparathyroid hormone (PTH) secretion-inhibiting factors, such as aluminum, magnesium, 25-hydroxyvitamin D, and calcitriol were excluded as a cause for these changes. We suggest that mineral metabolism should be carefully observed during interferon treatment in dialysis patients.


Assuntos
Hiperparatireoidismo/induzido quimicamente , Interferons/efeitos adversos , Falência Renal Crônica/terapia , Diálise Renal , Cálcio/sangue , Feminino , Rejeição de Enxerto , Hepatite C Crônica/complicações , Humanos , Interferons/uso terapêutico , Transplante de Rim , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Fósforo/sangue
20.
Anal Bioanal Chem ; 378(3): 563-75, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14564440

RESUMO

This paper is a review with more than 100 references discussing the immunochemical methods reported in the literature for the most important man-made chemicals with suspected endocrine disrupting activity. Details regarding immunizing hapten design, antibody production, and the features (limit of detection, dynamic range, specificity) of the most important immunochemical methods developed (ELISA, FIIA, immunosorbents, immunosensors, etc.) are presented for important environmental pollutants such as bisphenol A, phthalates, alkylphenol polyethoxylates, alkylphenols, polychlorinated biphenyl compounds, and dioxins. Availability of commercial reagents and methods is reported.


Assuntos
Glândulas Endócrinas/efeitos dos fármacos , Imunoensaio/métodos , Xenobióticos/análise , Animais , Cromatografia de Afinidade/métodos , Humanos , Xenobióticos/toxicidade
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