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Human parotid and submandibular glands were studied using histological techniques. Proteins rich in arginine, tyrosine, cystine-cysteine and tryptophan were present within secretory granules of seromucous acini and ducts of both glands. Acid phosphatase, ali-esterase, peroxidase and 3-beta-steroid-dehydrogenase were also demonstrated in the two glands. 相似文献
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Fadhlaoui-Zid Karima Cossu Piero Sanna Daria Scarpa Fabio Lai Tiziana Castelli Alberto Casu Marco Maltagliati Ferruccio 《Hydrobiologia》2021,848(18):4225-4240
Hydrobiologia - Recent research hypothesised that the Siculo-Tunisian Strait might fit, at least for some species, the picture of a genetic transitional zone instead of a sharp genetic break... 相似文献
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Andrea Cossu Ele Ferrannini Poupak Fallahi Alessandro Antonelli Leonardo A. Sechi 《Cytokine》2013,61(2):337-339
Recently Mycobacterium avium subsp. paratuberculosis (Map) was associated to type 1 diabetes mellitus (T1DM). In this study we investigated for Map presence in children affected by T1DM compared to healthy children. A pool of 212 sera from T1DM children at onset was compared to sera from 57 healthy children for humoral immune response towards the Map specific protein MAP3738c by ELISA. Serum concentrations of CXCL10 (pro-Th1) and CCL2 (pro-Th2) chemokines were also measured in both sera pool. Results showed that T1DM children had a stronger seropositivity towards MAP3738c protein compared to healthy children. Data highlighted also the correlation between serum activity of T1DM patients towards the specific protein of Map and the increase of CXCL10 concentration if compared to non-diabetic subjects. In conclusion, an immune response to Map in T1DM patients at onset was observed and this may indicate a role of the bacterium in triggering or precipitating the disease. 相似文献
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Geromy G. Moore Jacalyn L. Elliott Rakhi Singh Bruce W. Horn Joe W. Dorner Eric A. Stone Sofia N. Chulze German G. Barros Manjunath K. Naik Graeme C. Wright Kerstin Hell Ignazio Carbone 《PLoS pathogens》2013,9(8)
Aflatoxins are produced by Aspergillus flavus and A. parasiticus in oil-rich seed and grain crops and are a serious problem in agriculture, with aflatoxin B1 being the most carcinogenic natural compound known. Sexual reproduction in these species occurs between individuals belonging to different vegetative compatibility groups (VCGs). We examined natural genetic variation in 758 isolates of A. flavus, A. parasiticus and A. minisclerotigenes sampled from single peanut fields in the United States (Georgia), Africa (Benin), Argentina (Córdoba), Australia (Queensland) and India (Karnataka). Analysis of DNA sequence variation across multiple intergenic regions in the aflatoxin gene clusters of A. flavus, A. parasiticus and A. minisclerotigenes revealed significant linkage disequilibrium (LD) organized into distinct blocks that are conserved across different localities, suggesting that genetic recombination is nonrandom and a global occurrence. To assess the contributions of asexual and sexual reproduction to fixation and maintenance of toxin chemotype diversity in populations from each locality/species, we tested the null hypothesis of an equal number of MAT1-1 and MAT1-2 mating-type individuals, which is indicative of a sexually recombining population. All samples were clone-corrected using multi-locus sequence typing which associates closely with VCG. For both A. flavus and A. parasiticus, when the proportions of MAT1-1 and MAT1-2 were significantly different, there was more extensive LD in the aflatoxin cluster and populations were fixed for specific toxin chemotype classes, either the non-aflatoxigenic class in A. flavus or the B1-dominant and G1-dominant classes in A. parasiticus. A mating type ratio close to 1∶1 in A. flavus, A. parasiticus and A. minisclerotigenes was associated with higher recombination rates in the aflatoxin cluster and less pronounced chemotype differences in populations. This work shows that the reproductive nature of the population (more sexual versus more asexual) is predictive of aflatoxin chemotype diversity in these agriculturally important fungi. 相似文献
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Chiara Zoppellaro Anna Bin Paola Brun Serena Banzato Veronica Macchi Ignazio Castagliuolo Maria Cecilia Giron 《PloS one》2013,8(8)
Adenosine plays an important role in regulating intestinal motility and inflammatory processes. Previous studies in rodent models have demonstrated that adenosine metabolism and signalling are altered during chronic intestinal inflammatory diseases. However, the involvement of the adenosinergic system in the pathophysiology of gut dysmotility associated to a primary neurodysfunction is still unclear. Recently, we showed that the neurotropic Herpes simplex virus type-1 (HSV-1), orally inoculated to rodents, infects the rat enteric nervous system (ENS) and affects gut motor function without signs of systemic infection. In this study we examined whether changes in purinergic metabolism and signaling occur during permanent HSV-1 infection of rat ENS. Using isolated organ bath assays, we found that contraction mediated by adenosine engagement of A1 or A2A receptors was impaired at 1 and 6 weeks post-viral administration. Immunofluorescence studies revealed that viral infection of ENS led to a marked redistribution of adenosine receptors: A1 and A2B receptors were confined to the muscle layers whereas A2A and A3 receptors were expressed mainly in the myenteric plexus. Viral-induced ENS neurodysfunction influenced adenosine metabolism by increasing adenosine deaminase and CD73 levels in longitudinal muscle-myenteric plexus with no sign of frank inflammation. This study provides the first evidence for involvement of the adenosinergic system during HSV-1 infection of the ENS. As such, this may represent a valid therapeutic target for modulating gut contractility associated to a primary neurodysfunction. 相似文献
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