Publications by authors named "Gustavo Gimenez"

Electrochemical sensors have become increasingly relevant in fields such as medicine, environmental monitoring, and industrial process control. Selectivity, specificity, sensitivity, signal reproducibility, and robustness are among the most important challenges for their development, especially when the target compound is present in low concentrations or in complex analytical matrices. In this context, electrode modification with Mesoporous Thin Films (MTFs) has aroused great interest in the past years.

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Bacterial wilt caused by the pathogen Ralstonia solanacearum is a devastating disease of potato crops. Harmonizing immunity to pathogens and crop yield is a balance between productive, economic, and environmental interests. In this work, the agronomic performance of two events of potato cultivar INIA Iporá expressing the Arabidopsis thaliana EFR gene (Iporá EFR 3 and Iporá EFR 12) previously selected for their high resistance to bacterial wilt was evaluated under pathogen-free conditions.

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Identification of allergenic IgE epitopes is instrumental for the development of novel diagnostic and prognostic methods in food allergy. In this work, we present the quantification and validation of a Bead-Based Epitope Assay (BBEA) that through multiplexing of epitopes and multiple sample processing enables completion of large experiments in a short period of time, using minimal quantities of patients' blood. Peptides that are uniquely coupled to beads are incubated with serum or plasma samples, and after a secondary fluorophore-labeled antibody is added, the level of fluorescence is quantified with a Luminex reader.

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Given its ability to induce both humoral and cellular immune responses, NY-ESO-1 has been considered a suitable antigen for a cancer vaccine. Despite promising results from early-phase clinical studies in patients with melanoma, NY-ESO-1 vaccine immunotherapy has not been widely investigated in larger trials; consequently, many questions remain as to the optimal vaccine formulation, predictive biomarkers, and sequencing and timing of vaccines in melanoma treatment. We conducted an adjuvant phase I/II clinical trial in high-risk resected melanoma to optimize the delivery of poly-ICLC, a TLR-3/MDA-5 agonist, as a component of vaccine formulation.

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Background: The consumption of lentil is common in the Mediterranean area and is one of the causes of IgE-mediated food allergy in many countries. Len c 1 is a well-defined allergen of lentil and approximately 80% of the patients with lentil allergy recognize the purified Len c 1 protein. We sought to identify IgE and IgG4 sequential epitopes of Len c 1 in patients with red and/or green lentil allergy.

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In this paper, a systematic study regarding the effect of the mesoporous structure over Au nanoparticles (NPs) growth inside and through the pores of mesoporous TiO2 thin films (MTTFs) is presented, and the effect of such characteristics over the composites' sensing capabilities is evaluated. Highly stable MTTFs with different pore diameters (range: 4-8 nm) and pore arrangements (body- and face-centered cubic) were synthesized and characterized. Au NPs were grown inside the pores, and it was demonstrated-through a careful physicochemical characterization-that the amount of incorporated Au and NP size depends on the pore array; being higher for bigger pore diameters and face-centered cubic structures.

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Mesoporous oxide thin films (MOTF) present very high surface areas and highly controlled monodisperse pores in the nanometer range. These features spurred their possible applications in separation membranes and permselective electrodes. However, their performance in real applications is limited by their reactivity.

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Background: In a recent trial of milk oral immunotherapy (MOIT) with or without omalizumab in 55 patients with milk allergy treated for 28 months, 44 of 55 subjects passed a 10-g desensitization milk protein challenge; 23 of 55 subjects passed the 10-g sustained unresponsiveness (SU) challenge 8 weeks after discontinuing MOIT.

Objective: We sought to determine whether IgE and IgG antibody binding to allergenic milk protein epitopes changes with MOIT and whether this could predict the development of SU.

Methods: By using a novel high-throughput Luminex-based assay to quantitate IgE and IgG antibody binding to 66 sequential epitopes on 5 milk proteins, serum samples from 47 subjects were evaluated before and after MOIT.

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Background: The majority of children with cow's milk allergy (CMA) tolerate baked milk. However, reactivity to fermented milk products such as yogurt/cheese has not been previously evaluated. We sought to determine whether children with CMA could tolerate yogurt/cheese and whether a patient's IgE and IgG4-binding pattern to milk protein epitopes could distinguish clinical reactivity.

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The aim of this study was to analyze the reproductive behavioral responses in Australian Merino rams, to identify those related to a faster training for semen collection with an artificial vagina. Eight Australian Merino rams, aged 1.5 years and with no prior sexual experience, were randomly selected from an extensively grazed flock.

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IgE epitope mapping of food allergens contributes to a better understanding of the pathogenesis of food allergy and may become an additional tool for food allergy diagnosis/prognosis. Microarray platforms which allow for simultaneous screening of a large number of peptides corresponding to the sequences of food allergens are ideally suited for large-scale IgE epitope mapping. Here we describe the method of performing a reliable and sensitive peptide microarray immunoassay, which was developed in our lab and results in the identification of candidate IgE epitope biomarkers useful in determining allergic disease severity and prognosis, as well as in the prediction of treatment outcomes.

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Background: Oral immunotherapy (OIT) with cow's milk (CM) has been reported to induce a number of specific antibody responses, but these remain to be fully characterized. Our objective was to explore whether IgE and IgG4 epitope binding profiles could predict the risk of side effects during CM OIT.

Methods: The study population consisted of 32 children (6-17 yr of age) with CM allergy: 26 children who successfully completed OIT and six children who discontinued therapy due to adverse reactions.

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Stability during digestion is considered an important feature in determining the allergenicity of food proteins. This study aimed to provide an immunological characterisation of the digestion products of the major cow's milk allergen β-casein (β-CN) produced by in vitro orogastrointestinal hydrolysis with simulated and human digestive fluids. β-CN was unaffected by oral digestion, but quickly broke down during the early stages of gastric digestion.

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Background: Patients with peanut allergy have highly stable pathologic antibody repertoires to the immunodominant B-cell epitopes of the major peanut allergens Ara h 1 to 3.

Objective: We used a peptide microarray technique to analyze the effect of treatment with peanut oral immunotherapy (OIT) on such repertoires.

Methods: Measurements of total peanut-specific IgE (psIgE) and peanut-specific IgG(4) (psIgG(4)) were made with CAP-FEIA.

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Background: Peanut allergy is relatively common, typically permanent, and often severe. Double-blind, placebo-controlled food challenge is considered the gold standard for the diagnosis of food allergy-related disorders. However, the complexity and potential of double-blind, placebo-controlled food challenge to cause life-threatening allergic reactions affects its clinical application.

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Peptides derived from dietary antigens such as bovine milk caseins are opioid receptor ligands and contribute to schizophrenia-associated hyperpeptidemia and hyperpeptiduria. The IgG antibody response to bovine caseins is increased in schizophrenia and recent onset psychosis. To identify specific casein peptide sequences that are antigenic in patients vs controls, we measured serum IgG binding to 10-26 amino acid long linear epitopes of casein with immunoassays for the entire group (n=95 recent onset psychosis; n=103 long-term schizophrenia; n=65 control), and with peptide microarray libraries in a casein-sensitive subset (n=14 recent onset; n=10 control).

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