Celiac disease detection using a transglutaminase electrochemical immunosensor fabricated on nanohybrid screen-printed carbon electrodes

Celiac disease is a gluten-induced autoimmune enteropathy characterized by the presence of tissue tranglutaminase (tTG) autoantibodies. A disposable electrochemical immunosensor (EI) for the detection of IgA and IgG type anti-tTG autoantibodies in real patient’s samples is presented. Screen-printed carbon electrodes (SPCE) nanostructurized with carbon nanotubes and gold nanoparticles were used as the transducer surface. This transducer exhibits the excellent characteristics of carbon–metal nanoparticle hybrid conjugation and led to the amplification of the immunological interaction. The immunosensing strategy consisted of the immobilization of tTG on the nanostructured electrode surface followed by the electrochemical detection of the autoantibodies present in the samples using an alkaline phosphatase (AP) labelled anti-human IgA or IgG antibody. The analytical signal was based on the anodic redissolution of enzymatically generated silver by cyclic voltammetry. The results obtained were corroborated with a commercial ELISA kit indicating that the electrochemical immunosensor is a trustful analytical screening tool.

Voltammetric immunosensor for the diagnosis of celiac disease based on the quantification of anti-gliadin antibodies

Antibodies against gliadin are used to detect celiac disease (CD) in patients. An electrochemical immunosensor for the voltammetric detection of human anti-gliadin antibodies (AGA) IgA and AGA IgG in real serum samples is proposed. The transducer surface consists of screen-printed carbon electrodes modified with a carbon nanotube/gold nanoparticle hybrid system, which provides a very useful surface for the amplification of the immunological interactions. The immunosensing strategy is based on the immobilization of gliadin, the antigen for the autoantibodies of interest, onto the nanostructured surface. The antigen–antibody interaction is recorded using alkaline phosphatase labeled anti-human antibodies and a mixture of 3-indoxyl phosphate with silver ions (3-IP/Ag+) was used as the substrate. The analytical signal is based on the anodic redissolution of the enzymatically generated silver by cyclic voltammetry. The electrochemical behavior of this immunosensor was carefully evaluated assessing aspects as sensitivity, non-specific binding and matrix effects, and repeatability and reproducibility. The results were supported with a commercial ELISA test.

Celiac disease diagnosis and gluten-free food analytical control

Celiac disease (CD) is an autoimmune enteropathy, characterized by an inappropriate T-cell-mediated immune response to the ingestion of certain dietary cereal proteins in genetically susceptible individuals. This disorder presents environmental, genetic, and immunological components. CD presents a prevalence of up to 1% in populations of European ancestry, yet a high percentage of cases remain underdiagnosed. The diagnosis and treatment should be made early since untreated disease causes growth retardation and atypical symptoms, like infertility or neurological disorders. The diagnostic criteria for CD, which requires endoscopy with small bowel biopsy, have been changing over the last few decades, especially due to the advent of serological tests with higher sensitivity and specificity. The use of serological markers can be very useful to rule out clinical suspicious cases and also to help monitor the patients, after adherence to a gluten-free diet. Since the current treatment consists of a life-long glutenfree diet, which leads to significant clinical and histological improvement, the standardization of an assay to assess in an unequivocal way gluten in gluten-free foodstuff is of major importance.

An electrochemical deamidated gliadin antibody immunosensor for celiac disease clinical diagnosis

The first electrochemical immunosensor (EI) for the detection of antibodies against deamidated gliadin peptides (DGP) is described here. A disposable nanohybrid screen-printed carbon electrode modified with DGP was employed as the transducer's sensing surface. Real serumsampleswere successfully assayed and the results were corroborated with an ELISA kit. The presented EI is a promising analytical tool for celiac disease diagnosis.

Multiplexed electrochemical immunosensor for detection of celiac disease serological markers

Celiac disease (CD) is a gluten-induced autoimmune enteropathy characterized by the presence of antibodies against gliadin (AGA) and anti-tissue transglutaminase (anti-tTG) antibodies. A disposable electrochemical dual immunosensor for the simultaneous detection of IgA and IgG type AGA and antitTG antibodies in real patient’s samples is presented. The proposed immunosensor is based on a dual screen-printed carbon electrode, with two working electrodes, nanostructured with a carbon–metal hybrid system that worked as the transducer surface. The immunosensing strategy consisted of the immobilization of gliadin and tTG (i.e. CD specific antigens) on the nanostructured electrode surface. The electrochemical detection of the human antibodies present in the assayed serum samples was carried out through the antigen–antibody interaction and recorded using alkaline phosphatase labelled anti-human antibodies and a mixture of 3-indoxyl phosphate with silver ions was used as the substrate. The analytical signal was based on the anodic redissolution of enzymatically generated silver by cyclic voltammetry. The results obtained were corroborated with commercial ELISA kits indicating that the developed sensor can be a good alternative to the traditional methods allowing a decentralization of the analyses towards a point-of-care strategy.

Effects of a home-based exercise program in body composition, abdominal fat and lipid profile in patients with coronary artery disease

Introduction: Coronary artery disease and aging seems to be associated with a sedentary lifestyle, contributing to increased abdominal fat and consequently metabolic complications. The exercise can break this cycle by stimulating lipolysis and the use of fatty acids. In Europe there is still a lack of cardiac rehabilitation programmes in hospitals, therefore, this study aims to demonstrate the advantages of implementing home-based exercise programmes, as well as, their effects on cardiovascular prevention. This study analyzed the effects of a home-based exercise programme, in patients with coronary artery disease (myocardial infarction for 1 year), in body composition, abdominal fat, lipid profile. Methods: An ongoing randomized controlled trial with a sample of 20 participants were randomly allocated to intervention (n = 10) and control groups (n = 10). Intervention group performed a specific exercise programme during 8 weeks, consisting of ten home based exercises taking into account flexibility, muscle endurance and strength as well as cardiovascular endurance. Skinfolds thickness were measure to calculate the percentage of total fat: Skinfolds used were suprailiac, abdominal horizontal and vertical. Body mass index calculation and blood tests for lipidic profile were performed. Results: After eight weeks the intervention group decreased significantly the percentage of total fat (p < 0.05), the suprailiac skinfold (p < 0.05), the abdominal horizontal and vertical skinfold (p < 0.05) when compared with control group. In the intervention group it was observed after 8 weeks a significant decrease in body mass index, LDL-cholesterol and triglycerides. Conclusions: Home-based exercise programme influenced body composition, abdominal fat and lipid profile. These results highlight the importance of implementing home based exercises that are easy and cheap to implement in cardiac patients, in order to promote health and reduce cardiovascular risk factors.

Effects of microcurrents and physical exercise on the abdominal fat: a randomized controlled trial in patients with coronary artery disease

Objectives: Coronary artery disease are associated with decreased levels of physical activity, contributing to increases in abdominal fat and consequently the metabolic risk. The use of microcurrents is an innovative and effective method to increase lipolytic rate of abdominal adipocytes. This study aims to investigate the effects of microcurrents with a homebased exercise program on total, subcutaneous and visceral abdominal adipose tissue in subjects with coronary artery disease. Methods: This controlled trial included 44 subjects with myocardial infarction, randomly divided into Intervention Group 1 (IG1; n = 16), Intervention Group 2 (IG2; n = 12) and Control Group (CG; n = 16). IG1 performed a specific exercise program at home during 8 weeks, and IG2 additionally used microcurrents on the abdominal region before the exercise program. All groups were subjected to health education sessions. Computed Tomography was used to evaluate abdominal, subcutaneous and visceral fat, accelerometers to measure habitual physical activity and the semiquantitative Food Frequency Questionnaire for dietary intake. Results: After 8 weeks, IG2 showed a significantly decreased in subcutaneous fat (p ≤ 0.05) when compared to CG. Concerning visceral fat, both intervention groups showed a significant decrease in comparison to the CG (p ≤ 0.05). No significant changes were found between groups on dietary intake and habitual physical activity, except for sedentary activity that decreased significantly in IG2 in comparison with CG (p ≤ 0.05). Conclusions: This specific exercise program showed improvements in visceral fat in individuals with coronary artery disease. Microcurrent therapy associated with a home-based exercise program suggested a decreased in subcutaneous abdominal fat.

Effects of the Mediterranean diet and exercise in subjects with coronary artery disease

Introduction The association of the Mediterranean diet and exercise appears to have a protective role, reducing cardiovascular risk. This study investigated the effects of education sessions on the Mediterranean diet and an exercise program in modifying eating behaviors, body composition and abdominal fat. Methods An experimental study was performed on 20 subjects with known coronary heart disease randomly assigned to experimental (n=10) and control (n=10) groups. Both groups received education sessions on the Mediterranean diet, but the experimental group also followed an eight-week program of specific exercises. A semiquantitative food frequency questionnaire was administered to analyze food intake, bioimpedance was used to measure weight, fat mass and lean mass, and waist circumference was measured to calculate waist-to-height ratio. Results After eight weeks, protein (p<0.05) and cholesterol (p<0.05) intake in the experimental group had decreased significantly compared with the control group. Between the beginning and end of the study, there were significant decreases in the control group in carbohydrate (p<0.05) and saturated fat intake (p<0.05). In both groups the percentage of total fat (p<0.05) and fat mass (p<0.05) was significantly decreased. In the experimental group the waist-to-height ratio was significantly reduced (p<0.05). Conclusion The Mediterranean diet reduced carbohydrate and saturated fat intake, reflected in reduced fat mass. The association of the exercise program showed additional benefits in reduction of protein and cholesterol intake and abdominal fat.

Effects of microcurrents and physical exercise on the abdominal fat in patients with coronary artery disease

Introduction Coronary artery disease is associated with decreased levels of physical activity, contributing to increases in abdominal fat and consequently increasing metabolic risk. The innovative use of microcurrents may be an effective method to increase the lipolytic rate of abdominal adipocytes. This study aimed to investigate the effects of utilizing microcurrents in a home-based exercise program in subjects with coronary artery disease to assess changes in total, subcutaneous and visceral abdominal adipose tissue. Methods This controlled trial included 44 subjects with myocardial infarction, randomly divided into Intervention Group 1 (IG1; n = 16), Intervention Group 2 (IG2; n = 12) and Control Group (CG; n = 16). IG1 performed a specific exercise program at home during 8 weeks, and IG2 additionally used microcurrents on the abdominal region before the exercise program. All groups were given health education sessions. Computed tomography was used to evaluate abdominal, subcutaneous and visceral fat, accelerometers to measure habitual physical activity and the semi-quantitative food frequency questionnaire for dietary intake. Results After 8 weeks, IG2 showed a significantly decrease in subcutaneous fat (p ≤ 0.05) when compared to CG. Concerning visceral fat, both intervention groups showed a significant decrease in comparison to the CG (p ≤ 0.05). No significant changes were found between groups on dietary intake and habitual physical activity, except for sedentary activity that decreased significantly for IG2 in comparison with CG (p ≤ 0.05). Conclusion This specific home-based exercise program using microcurrent therapy for individuals with coronary artery disease showed improvements in visceral and subcutaneous abdominal fat.