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421.
Rossana Perrone Omar Macadar Ana Silva 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2009,195(5):501-514
Brachyhypopomus pinnicaudatus (pulse-type weakly electric fish) is a gregarious species that displays reproductive behavior and agonistic encounters between
males only during the breeding season. During social interactions, in addition to its basal electric organ discharge (EOD),
fish emit social electric signals (SESs) in the contexts of reproduction and intrasexual aggression. We reproduced natural
behavior in laboratory settings: SESs recorded in the field are indistinguishable from those observed in our experimental
setup. SESs are nocturnal, change seasonally and exhibit sexual dimorphism. This study provides an exhaustive characterization
and classification of SESs produced by males and females during the breeding season. In male–female dyads, males produce accelerations
and chirps while females interrupt their EODs. The same SESs are observed in male–male dyads. We present a novel, thorough
classification of male chirps into four independent types (A, B, C, and M) based on their duration and internal structure.
The type M chirp is only observed in male–male dyads. Chirps and interruptions, both in male–female and male–male dyads, are
emitted in bouts, which are also grouped throughout the night. Our data suggest the existence of a sophisticated electric
dialog during reproductive and aggressive interaction whose precise timing and behavioral significance are being investigated. 相似文献
422.
Sabrina S.P. Damianse Gilvan C. Nascimento Viviane C.C. Rocha Ana Gisélia P.A. C. Nascimento Nadja C. Gaido Rossana S.S. Azulay Wellyandra C. dos Santos Vandilson P. Rodrigues Ana Rosa P. Quidute Marcelo Magalhães Manuel dos S. Faria 《Endocrine practice》2022,28(5):509-514
ObjectiveMultiple endocrine neoplasia type 1 (MEN1) is a rare genetic syndrome characterized by parathyroid, anterior pituitary, and/or duodenopancreatic neuroendocrine tumors. Studies have indicated that investigating primary hyperparathyroidism (pHPT) with subsequent genetic screening may be an essential tool for the early diagnosis of MEN1 in patients with pituitary tumors (PTs). This study aimed to investigate the presence of pHPT in patients with PTs and, subsequently, to screen for genetic mutations and related tumors in patients with MEN1 syndrome.MethodsThis study included 255 patients with PTs who were assessed for the presence of MEN1 by serum calcium and parathyroid hormone measurements. Mutation screening of the MEN1, CDKN1B, and AIP genes was performed in the index cases showing the MEN1 phenotype.ResultsFive patients with PTs presented a clinical condition compatible with MEN1. These patients had a younger age of onset and a more severe clinical condition. Genetic analysis identified a frameshift mutation in the MEN1 gene in one of the cases with the MEN1 phenotype, but point mutations in CDKN1B and AIP were not detected in any of these patients.ConclusionOur results show that periodic screening for pHPT in patients with PTs may be useful to detect MEN1 syndrome; thus, it is recommended in those patients with both findings a genetic analysis of MEN1 gene and an additional search of related tumors. By contrast, our data suggest that CDKN1B and AIP mutations do not seem to play a relevant role in the pathogenesis of MEN1. 相似文献
423.
Rossana de Aguiar Cordeiro Kharla Rabelo Nobre Patoilo Silviane Bandeira Praciano Delia Jessica Astete Medrano Francisca Jakelyne de Farias Marques Liline Maria Soares Martins Kelsen Dantas Eulalio Antônio de Deus Filho Maria do Amparo Salmito Cavalvanti Maria Auxiliadora Bezerra Fechine Raimunda Samia Nogueira Brilhante Zoilo Pires de Camargo Marcos Fábio Gadelha Rocha José Júlio Costa Sidrim 《Mycopathologia》2013,175(1-2):25-32
Serologic diagnosis has been presented as a safe alternative for coccidioidomycosis. However, commercial kits based on coccidioidal antibodies available in the USA are considered too expensive for laboratories outside that country. In this study, we describe the preparation of antigens for detection of human coccidioidal antibodies by the immunodiffusion test (ID) and enzyme immunoassay (EIA). Antigens were tested against serum samples from patients with coccidioidomycosis, histoplasmosis and paracoccidioidomycosis, as well as healthy individuals. The highest reactivity in the ID tests was seen in the F0-90 antigen. In the EIAs, the best results were obtained with the F60-90 antigen. None of the serum samples from healthy individuals were recognized by any of the antigen extracts tested by ID or EIA. In conclusion, the F0-90 and F60-90 antigens have the potential to be commercially employed in presumptive diagnosis of coccidioidomycosis by ID or EIA, respectively. The tests could improve serological diagnosis of coccidioidomycosis in South America. 相似文献
424.
Elibeth Mirasol-Meléndez Luis G. Brieba Corina Díaz-Quezada Marisol López-Hidalgo Elisa E. Figueroa-Angulo Leticia Ávila-González Rossana Arroyo-Verástegui Claudia G. Benítez-Cardoza 《Parasitology international》2018,67(4):444-453
Trichomonas vaginalis is the protist parasite that causes the most common, non-viral sexually transmitted infection called trichomonosis. Enolase is a moonlighting protein that apart from its canonical function as a glycolytic enzyme, serves as a plasminogen receptor on the cell surface of T. vaginalis and, in consequence, it has been stablished as a virulence factor in this parasite. In the Trichomonas vaginalis sequence database there are nine genes annotated as enolase. In this work, we analyzed these genes as well as their products. We found that seven out of nine genes might indeed perform enolase activity, whereas two genes might have been equivocally identified, or they might be pseudogenes. Furthermore, a combination of qRT-PCR and proteomic approaches was used to assess, for the first time, the expression of these genes in the highly virulent mexican isolate of T. vaginalis CNCD-147 at different iron concentrations. We could find peptides corresponding to enolases encoded by genes TVAG_464170, TVAG_043500 and TVAG_329460. Moreover, we identified two distinctive characteristics within enolases from Trichomonas vaginalis. One of them corresponds to three key substitutions within one of the loops of the active site, compared to host enolase. The other, is a unique N-terminal motif, composed of 15 to 18 residues, on all the potentially active enolases, whose function still has to be stablished. Both differential features merit further studies as potential drug and vaccine targets as well as diagnosis markers. These findings offer new possibilities to fight trichomonosis. 相似文献
425.
Dario Sirabella Elisa Cimetta Gordana Vunjak-Novakovic 《Experimental biology and medicine (Maywood, N.J.)》2015,240(8):1008-1018
The pressing need for effective cell therapy for the heart has led to the investigation of suitable cell sources for tissue replacement. In recent years, human pluripotent stem cell research expanded tremendously, in particular since the derivation of human-induced pluripotent stem cells. In parallel, bioengineering technologies have led to novel approaches for in vitro cell culture. The combination of these two fields holds potential for in vitro generation of high-fidelity heart tissue, both for basic research and for therapeutic applications. However, this new multidisciplinary science is still at an early stage. Many questions need to be answered and improvements need to be made before clinical applications become a reality. Here we discuss the current status of human stem cell differentiation into cardiomyocytes and the combined use of bioengineering approaches for cardiac tissue formation and maturation in developmental studies, disease modeling, drug testing, and regenerative medicine. 相似文献
426.
Giovanna Boi Carla Rossana Scalia Rossella Gendusa Susanna Ronchi Giorgio Cattoretti 《The journal of histochemistry and cytochemistry》2016,64(1):18-31
Drying of the tissue section, partial or total, during immunostaining negatively affects both the staining of tissue antigens and the ability to remove previously deposited antibody layers, particularly during sequential rounds of de-staining and re-staining for multiple antigens. The cause is a progressive loss of the protein-associated water up to the removal of the non-freezable water, a step which abolishes the immunoavailability of the epitope. In order to describe and prevent these adverse effects, we tested, among other substances, sugars, which are known to protect unicellular organisms from freezing and dehydration, and stabilize drugs and reagents in solid state form in medical devices. Disaccharides (lactose, sucrose) prevented the air drying-induced antigen masking and protected tissue-bound antigens and antibodies from air drying-induced damage. Complete removal of the bound antibody layers by chemical stripping was permitted if lactose was present during air drying. Lactose, sucrose and other disaccharides prevent air drying artifacts, allow homogeneous, consistent staining and the reuse of formalin-fixed, paraffin-embedded tissue sections for repeated immunostaining rounds by guaranteeing constant staining quality in suboptimal hydration conditions. 相似文献
427.
428.
429.
Dione B. Rolim Marcos F. G. Rocha Raimunda S. N. Brilhante Rossana A. Cordeiro Natanael P. Leito-Junior Timothy J. J. Inglis Jos J. C. Sidrim 《Applied microbiology》2009,75(4):1215-1218
Melioidosis has been considered an emerging disease in Brazil since the first cases were reported to occur in the northeast region. This study investigated two municipalities in Ceará state where melioidosis cases have been confirmed to occur. Burkholderia pseudomallei was isolated in 26 (4.3%) of 600 samples in the dry and rainy seasons. 相似文献
430.
Rossana DArienzo Francesco Maurano Paola Lavermicocca Ezio Ricca Mauro Rossi 《Cytokine》2009,48(3):254-259
Probiotic strains play an important role in modulating activities in the gut-associated lymphoid tissue. Elucidation of the mechanisms that mediate probiotic-driven immunomodulation may facilitate their therapeutic application for specific immune-mediated diseases or for prophylaxis. In this study, we explored the effect of different Lactobacillus spp. and Bifidobacterium lactis in transgenic mice expressing the human DQ8 heterodimer, a HLA molecule linked to Celiac Disease (CD). In vitro analysis on immature bone marrow-derived dendritic cells (iBMDCs) showed that all strains up-regulated surface B7-2 (CD86), indicative of DC maturation, however, with different intensity. No strain induced appreciable levels of IL-10 or IL-12 in iBMDCs, whereas TNF-α expression was essentially elicited by Lactobacillus paracasei and Lactobacillus fermentum. Interestingly, these strains were found also to increase the antigen-specific TNF-α secretion in vivo, following co-administration of probiotic bacteria in mice mucosally immunized with the gluten component gliadin. Together these findings highlighted the ability of probiotics to exert strain-specific inductive rather than suppressive effects both on the innate and adaptive immunity in a mouse model of food antigen sensitivity. 相似文献