Human monoclonal islet specific autoantibodies share features of islet cell and 64 kDa antibodies

The first human monoclonal islet cell antibodies of the IgG class (MICA 1-6) obtained from an individual with Type 1 (insulin-dependent) diabetes mellitus were cytoplasmic islet cell antibodies selected by the indirect immunofluorescence test on pancreas sections. Surprisingly, they all recognized the 64 kDa autoantigen glutamate decarboxylase. In this study we investigated which typical features of cytoplasmic islet cell antibodies are represented by these monoclonals. We show by double immunofluorescence testing that MICA 1-6 stain pancreatic beta cells which is in agreement with the beta-cell specific expression of glutamate decarboxylase. In contrast an islet-reactive IgM monoclonal antibody obtained from a pre-diabetic individual stained all islet cells but lacked the tissue specificity of MICA 1-6 and must therefore be considered as a polyreactive IgM-antibody. We further demonstrate that MICA 1-6 revealed typical features of epitope sensitivity to biochemical treatment of the target tissue which has been demonstrated for islet cell antibodies, and which has been used to argue for a lipid rather than a protein nature of target antigens. Our results provide direct evidence that the epitopes recognized by the MICA are destroyed by methanol/chloroform treatment but reveal a high stability to Pronase digestion compared to proinsulin epitopes. Conformational protein epitopes in glutamate decarboxylase therefore show a sensitivity to biochemical treatment of sections such as ganglioside epitopes. MICA 1-6 share typical features of islet cell and 64 kDa antibodies and reveal that glutamate decarboxylase-reactive islet cell antibodies represent a subgroup of islet cell antibodies present in islet cell antibody-positive sera

Dinamica delle isole fluviali del Fiume Brenta tra Nove e Fontaniva

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Prova emprestada no processo civil

Divulgação dos SUMÁRIOS das obras recentemente incorporadas ao acervo da Biblioteca Ministro Oscar Saraiva do STJ. Em respeito à Lei de Direitos Autorais, não disponibilizamos a obra na íntegra.Localização na estante: 347.94(81) G195pCoordenado por: Teresa Arruda Alvim e Eduardo Talamini

Recombinant human preproinsulin expression, purification and reaction with insulin autoantibodies in sera from patients with insulin-dependent diabetes mellitus

A novel prokaryotic expression vector pGEX-6T was designed for high-level expression of recombinant fusion protein with a histidine-hexapeptide and glutathione-S-transferase at its N-terminus and the recombinant human preproinsulin at its C-terminus. Efficiency of expression was investigated in the Escherichia coli strain CAG456. The synthesized protein was sequestered in an insoluble form in inclusion bodies and was purified to homogeneity by one-step affinity chromatography based on the specific complex formation of the histidine-hexapeptide and a chelating matrix which was charged with Ni2+ ions. The antigenic nature of the purified recombinant preproinsulin fusion protein was evaluated by ELISA screening for insulin autoantibodies in selected sera from patients with recent-onset type 1 (insulin-dependent) diabetes mellitus classified by the existence of additional autoantibodies reactive against glutamic acid decarboxylase. 14% of the tested sera (n=43) conttained insulin autoantibodies which strongly recognized the recombinant human preproinsulin. Comparable measurements with both recombinant human preproinsulin and mature insulin suggested that the observed autoantigenicity of preproinsulin was mediated by the C-peptide or/and signal peptide

Association between Antibodies to the MR 67,000 Isoform of Glutamate Decarboxylase (GAD) and Type 1 (Insulin-Dependent) Diabetes Mellitus with Coexisting Autoimmune Polyendocrine Syndrome Type II

By using an immunoprecipitation assay, we analysed reactivity of autoantibodies to human recombinant GAD65 and GAD67 in sera from patients with autoimmune polyendocrine syndrome Type II (APS II) with and without Type 1 (insulin-dependent) diabetes mellitus (IDDM) compared to patients with organ-specific autoimmunity. Overall antibodies to GAD65 were correlated with IDDM in all study groups, whereas GAD67 antibodies were associated with IDDM when APS II coexists. Antibodies to GAD65 and GAD67 were detected in 13 (44.8%) and 7 (24.1%) out of 29 APS II patients with IDDM, but in only 4 (13.8%) and 2 (6.9%) out of 29 APS II patients without IDDM, respectively (p < 0.05). In short-standing IDDM (< 1 year), antibodies to GAD67 were significantly more frequent in patients with APS II (5 of 9 [55.6%] subjects) compared to matched diabetic patients without coexisting polyendocrinopathy (1 of 18 [5.6%] subjects) (p < 0.02). The levels of GAD65 (142 ± 90 AU) and GAD67 antibodies (178 ± 95 AU) were significantly higher in patients with polyglandular disease than in patients with isolated IDDM (91 ± 85 AU and 93 ± 57 AU) (p < 0.02). Interestingly, all 11 GAD67 antibody positive subjects also had GAD65 antibodies (p < 0.0001), and in 10 of 11 anti-GAD67 positive sera the GAD67 antibodies could be blocked by either GAD67 or GAD65, suggesting the presence of cross-reactive autoantibodies. No correlation was observed between GAD antibodies and age, sex or any particular associated autoimmune disease, besides IDDM. GAD antibodies were present in only 1 of 6 (16.7%) patients with APS Type I, in 1 of 26 (3.9%) patients with autoimmune thyroid disease but in none of the patients with Addison's disease (n = 16), pernicious anaemia (n = 7) or normal controls (n = 50). Our data suggest distinct antibody specificities reactive to GAD isoforms in APS II and IDDM, which might reflect different mechanisms of autoimmune response in IDDM with coexisting autoimmune polyendocrine autoimmunity

Quantification of Small Non-Coding RNAs Allows an Accurate Comparison of miRNA Expression Profiles

MicroRNAs (miRNAs) are highly conserved ∼22-mer RNA molecules, encoded by plants and animals that regulate the expression of genes binding to the 3′-UTR of specific target mRNAs. The amount of miRNAs in a total RNA sample depends on the recovery efficiency that may be significantly affected by the different purification methods employed. Traditional approaches may be inefficient at recovering small RNAs, and common spectrophotometric determination is not adequate to quantify selectively these low molecular weight (LMW) species from total RNA samples. Here, we describe the use of qualitative and quantitative lab-on-a-chip tools for the analysis of these LMW RNA species. Our data emphasize the close correlation of LMW RNAs with the expression levels of some miRNAs. We therefore applied our result to the comparison of some miRNA expression profiles in different tissues. Finally, the methods we used in this paper allowed us to analyze the efficiency of extraction protocols, to study the small (but significant) differences among various preparations and to allow a proper comparison of some miRNA expression profiles in various tissues

Interindividual variation and consistency of migratory behavior in the Eurasian woodcock

Diverse spatio-temporal aspects of avian migration rely on relatively rigid endogenous programs. However, flexibility in migratory behavior may allow effective coping with unpredictable variation in ecological conditions that can occur during migration. We aimed at characterizing inter- and intraindividual variation of migratory behavior in a forest-dwelling wader species, the Eurasian woodcock Scolopax rusticola, focusing on spatio-temporal consistency across repeated migration episodes. By satellite-tracking birds from their wintering sites along the Italian peninsula to their breeding areas, we disclosed a remarkable variability in migration distances, with some birds flying more than 6,000 km to Central Asian breeding grounds (up to 101\ub0E). Prebreeding migration was faster and of shorter duration than postbreeding migration. Birds moving over longer distances migrated faster during prebreeding migration, and those breeding at northernmost latitudes left their wintering areas earlier. Moreover, birds making longer migrations departed earlier from their breeding sites. Breeding site fidelity was very high, whereas fidelity to wintering areas increased with age. Migration routes were significantly consistent, both among repeated migration episodes and between pre- and postbreeding migration. Prebreeding migration departure date was not significantly repeatable, whereas arrival date to the breeding areas was highly repeatable. Hence, interindividual variation in migratory behavior of woodcocks was mostly explained by the location of the breeding areas, and spatial consistency was relatively large through the entire annual cycle. Flexibility in prebreeding migration departure date may suggest that environmental effects have a larger influence on temporal than on spatial aspects of migratory behavior

Habitat selection of the roe deer Capreolus capreolus (Artiodactyla, Cervidae) in an agroforestry system

The present study aimed at assessing the habitat preferences of the most widespread and abundant ungulate in Italy, the roe deer, in the Vallevecchia protected area (Venice). This area has been the object of naturalistic management and continuous environmental improvements in the last decades. Currently, the area is characterized by a high habitat heterogeneity, including deciduous woodlands, pine forests, wetlands, and farmlands. The study was carried out during the summers of 2017 and 2020. Data were collected along standardized transects, and the geo-localized records were divided into the corresponding habitats to calculate the Jacobs Index. In addition, chi-square test was applied, with the calculation of Pearson residuals to estimate the significance of associations to the habitats. The analyses show that in Vallevecchia the roe deer prefers woods and permanent meadows. Conversely, this ungulate avoids pine forests, wetlands and farmlands, despite their potential as sources of food and shelter. In line with other studies on agroforestry systems, wooded areas were most likely preferred because they provide shelter from disturbing factors and thermal stress, while meadows were likely chosen for trophic reasons. In this respect, we point out that in the studied area the preference for meadows was most likely due also to the availability of sprouts all year round, deriving from the constant mowing activities implemented in this habitat. In addition, our investigation underlines that the roe deer normally avoids maize and wheat crops, in accordance with similar studies. Moreover, the analyses highlight the preference for farmlands only if woods and grasslands are not present in the adjoining areas. Conversely, the proximity of these habitats results in a low impact on crops. In addition to encouraging the enforcement of current management actions in Vallevecchia, our results represent a contribution to a more effective management of the roe deer in agroforestry systems, aimed at limiting its impact in anthropized contexts and at achieving the conditions for a better coexistence of this deer with human activities