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  • 1
    In: Neotropical Biology and Conservation, Pensoft Publishers, Vol. 16, No. 2 ( 2021-05-20), p. 333-349
    Abstract: Wetlands currently have high rates of degradation, with more than 70% lost globally. In the central Monte Desert, Argentina, they are a scarce and limited resource for the biodiversity which depends on them. Waterbirds have been used as biological indicators of wetlands because they respond to fluctuations in food resources and to environmental changes in the short term. Here we analyse the seasonal variations in the structure of the waterbird assemblage from a relict wetland in this region. We carried out censuses of waterbirds in a 6-year period (between 2009 and 2019) during the southern summer and winter. We recorded 1875 individuals of 33 species of waterbirds during the summer and 677 individuals of 29 species during the winter. The grouping patterns of the waterbird assemblages differed between seasons (R = 0.35; p & lt; 0.01). Taxonomic diversity profiles showed greater diversity for all indexes ( q D) during the summer. The guild of invertivorous and omnivorous waders had a greater abundance of individuals during the summer ( p & lt; 0.05) and, together with the surface-feeding herbivores, contributed to the 87% of the dissimilarity of the assemblages between seasons. Phoenicopterus chilensis was the only species registered as threatened with national and international extinction. Relict wetlands, such as Laguna del Viborón, still have attributes of community diversity and represent the last refuges for waterbirds of the central Monte Desert. The information gathered in this study will contribute to the guidelines for integrated management plans and monitoring programmes for the conservation of the wetland and its biodiversity.
    Type of Medium: Online Resource
    ISSN: 2236-3777
    Language: Unknown
    Publisher: Pensoft Publishers
    Publication Date: 2021
    detail.hit.zdb_id: 2613449-4
    SSG: 12
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  • 2
    Online Resource
    Online Resource
    Springer Science and Business Media LLC ; 1941
    In:  Zeitschrift für Krebsforschung Vol. 51, No. 4-5 ( 1941-7), p. 487-496
    In: Zeitschrift für Krebsforschung, Springer Science and Business Media LLC, Vol. 51, No. 4-5 ( 1941-7), p. 487-496
    Type of Medium: Online Resource
    ISSN: 0171-5216 , 1432-1335
    RVK:
    Language: German
    Publisher: Springer Science and Business Media LLC
    Publication Date: 1941
    detail.hit.zdb_id: 1459285-X
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  • 3
    In: Zoologia, FapUNIFESP (SciELO), Vol. 35 ( 2018-08-30), p. 1-5
    Abstract: This communication describes the first records of byssal hairs on the postlarvae shells of Mytilusedulisplatensis d’Orbigny, 1842. The postlarvae used in this study were sampled on artificial collectors used for mussel culture in San Jorge Gulf, Sudoccidental Atlantic Ocean. A general description of the hairs is made as well as an exploratory analysis of their spatial distribution on the shell surface. The presence of these byssal hairs is suggested as a criterion to differentiate M.edulisplatensis from other mytilids.
    Type of Medium: Online Resource
    ISSN: 1984-4689
    Language: Unknown
    Publisher: FapUNIFESP (SciELO)
    Publication Date: 2018
    detail.hit.zdb_id: 2505776-5
    SSG: 12
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  • 4
    In: Microscopy Research and Technique, Wiley, Vol. 77, No. 10 ( 2014-10), p. 790-796
    Abstract: Non‐alcoholic fatty liver disease (NAFLD) is a clinical‐pathological syndrome that includes a wide spectrum of morphological alterations. In research, animal models are crucial in evaluating not only the pathogenesis of NAFLD and its progression, but also the therapeutic effects of various agents. Investigations on the ultrastructural features of NAFLD in humans are not copious, due to the difficulty to obtain human samples and to the long time of NAFLD to evolve. Translational comparative studies on the reliability of animal models in representing the histopathologic picture as seen in humans are missing. To overcome this lack of investigations, we compared the ultrastructural NAFLD features of an animal model versus human. Sprague‐Dawley rats were fed with a high fat diet (HFD) for 1–4 weeks, while control rats were fed with a standard diet. Human specimens were collected from patients with diagnosed fatty liver disease, undergoing liver biopsies or surgery. Rat and human samples were examined by light microscopy and by transmission and high resolution scanning electron microscopy. The present work demonstrated that NAFLD in animal model and in human, share overlapping ultrastructural features. In conclusion, animal HFD represent an appropriate tool in studying the pathogenesis of NAFLD. Microsc. Res. Tech. 77:790–796, 2014 . © 2014 Wiley Periodicals, Inc.
    Type of Medium: Online Resource
    ISSN: 1059-910X , 1097-0029
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2014
    detail.hit.zdb_id: 1474912-9
    SSG: 11
    SSG: 12
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  • 5
    Online Resource
    Online Resource
    Wiley ; 2007
    In:  Microscopy Research and Technique Vol. 70, No. 7 ( 2007-07), p. 607-616
    In: Microscopy Research and Technique, Wiley, Vol. 70, No. 7 ( 2007-07), p. 607-616
    Type of Medium: Online Resource
    ISSN: 1059-910X , 1097-0029
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2007
    detail.hit.zdb_id: 1474912-9
    SSG: 11
    SSG: 12
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  • 6
    In: Microscopy Research and Technique, Wiley, Vol. 84, No. 4 ( 2021-04), p. 675-681
    Abstract: Morphological and ultrastructural investigations are crucial for the identification and characterization of species such as microalgae, microorganisms that greatly change their morphology and physiology during their life cycle. Transmission electron microscopy (TEM) is an excellent tool for the ultrastructural observation of cells and their components. To date, limited ultrastructural studies have been carried out on microalgae, due to the difficulties in sample preparation. The aim of this work is to establish an appropriate fixation method that allows to better preserve the algal ultrastructure and test the suitability of the thawed algae for TEM observation. Fresh and thawed algae ( Coccomyxa melkonianii SCCA 048) were fixed with different TEM fixation methods (a mix of glutaraldehyde and paraformaldehyde for several incubation times, sometimes preceded by a prefixation in cold methanol). The ultrastructural images obtained from fresh algae were compared to those obtained from frozen biomass. The best morphological results were achieved by fixing fresh algae in 1% paraformaldehyde and 1.25% glutaraldehyde for 5 hr. Pretreating with frozen methyl alcohol reduced fixation time to 2 hr. Both fresh and frozen algae ultrastructure were rather well preserved also with 1% paraformaldehyde and 1.25% glutaraldehyde for 2 hr. Ultrastuctural morphological images of the thawed algae demonstrated that also frozen samples can be used in TEM research, widening specimen suitability by means of this technique.
    Type of Medium: Online Resource
    ISSN: 1059-910X , 1097-0029
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2021
    detail.hit.zdb_id: 1474912-9
    SSG: 11
    SSG: 12
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  • 7
    In: Oral Diseases, Wiley, Vol. 20, No. 8 ( 2014-11), p. 796-802
    Abstract: Amisulpride is reported to inhibit clozapine‐induced sialorrhea. Preclinically, clozapine evokes muscarinic‐M1‐type‐mediated secretion that, however, amisulpride does not reduce. Instead, amisulpride, without causing any overt secretion per se , enhances both nerve‐ and autonomimetic‐evoked salivation by unknown mechanism(s). Hypothesizing that amisulpride prepares the gland for secretion, we looked for ultrastructural events indicating secretory activity in intercellular canaliculi of serous/seromucous cells, that is , density increase in protrusions (reflecting anchored granules) and in microbuds (reflecting recycling membranes and/or vesicle secretion) and decrease in microvilli (reflecting the cytoskeletal re‐arrangement related to exocytosis). Material and Methods Rat parotid and submandibular glands were exposed to amisulpride in vivo or in vitro . Glands were processed for transmission electron and scanning electron microscopy and then morphometrically assessed. Results Cells were packed with secretory granules. The density of protrusions increased in both glands, whereas significant and parallel changes in microvilli and microbuds occurred only in parotid glands, and in vitro . Conclusions Amisulpride induced ultrastructural signs of secretory activity but to varying extent; in submandibular glands, in contrast to parotid glands, changes were not brought beyond the granular anchoring stage. Amisulpride may provide an overall readiness for secretion that will result in augmented responses to agonists, a phenomenon of potential interest in dry‐mouth treatment.
    Type of Medium: Online Resource
    ISSN: 1354-523X , 1601-0825
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2014
    detail.hit.zdb_id: 2008428-6
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  • 8
    In: The Anatomical Record, Wiley, Vol. 298, No. 11 ( 2015-11), p. 1911-1918
    Abstract: Type 2 diabetes mellitus represents one of the principal diseases that afflict the world population and is often associated with malfunction of salivary glands and consequent oral diseases. We recently described significant ultrastructural alterations in the human submandibular gland in diabetic patients without evident oral pathologies. Herein, an analogs morphometrical investigation was focused on the parotid gland in order to evaluate if one of the two glands is more affected by diabetes. Parotid fragments from diabetic and nondiabetic patients were fixed, dehydrated, and processed for light and electron microscopy. Serous cells were randomly photographed and the density and size of several structures involved in the secretory process were examined by morphometry. Scanning electron microscopy images revealed significant changes in the number of apically docked granules and vesicles, suggesting that the last steps in exocytosis are somehow altered in diabetic cells. Other variables analyzed by light and transmission electron microscopy such as the size of acini and secretory granules did not show significant changes, but comparison with previous data obtained with submandibular gland cells demonstrated that the two glands are affected differently. Anat Rec, 298:1911–1918, 2015. © 2015 Wiley Periodicals, Inc.
    Type of Medium: Online Resource
    ISSN: 1932-8486 , 1932-8494
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2015
    detail.hit.zdb_id: 2273240-8
    detail.hit.zdb_id: 2109216-3
    SSG: 12
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  • 9
    Online Resource
    Online Resource
    Wiley ; 2021
    In:  The Anatomical Record Vol. 304, No. 12 ( 2021-12), p. 2879-2890
    In: The Anatomical Record, Wiley, Vol. 304, No. 12 ( 2021-12), p. 2879-2890
    Abstract: Among the pathologies affecting the salivary glands, the Sjögren's syndrome (SS), an autoimmune disease, causes progressive destruction of the glandular tissue. The effect of SS is particularly evident on the labial glands and the morphological analysis of these minor glands is considered useful for diagnosis. Cevimeline hydrochloride (SNI), a selective muscarinic agonist drug, is one of the elective treatments for the hyposalivation due to SS, acting not only on major salivary glands, but also on labial glands since their secretion is primarily under parasympathetic control. Aim of this study is to describe the morphology of human labial glands treated with SNI by light, transmission, and high‐resolution scanning electron microscopy. Moreover, a morphometric analysis was applied to the light and transmission electron microscopy micrographs to obtain data that were then compared with analogous data collected on control and carbachol‐treated labial glands. Following SNI administration, the mucous tubules exhibited enlarged lumina, which were filled with a dense mucous secretion. Occasionally, small broken debris of the cells were retrieved into the lumen. In the mucous secretory cells, some mucous droplets fused to form a large vacuole‐like structure. Similarly, the seromucous acini showed both dilated lumina and canaliculi. These above reported signs of secretion were confirmed through morphometric analysis and a milder action of SNI than carbachol on labial parenchyma was observed. This study confirmed that SNI also evoked secretion on labial glands and that its effect is more physiologic than that of the pan‐muscarinic agonists.
    Type of Medium: Online Resource
    ISSN: 1932-8486 , 1932-8494
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2021
    detail.hit.zdb_id: 2273240-8
    detail.hit.zdb_id: 2109216-3
    SSG: 12
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  • 10
    Online Resource
    Online Resource
    Wiley ; 2018
    In:  The Anatomical Record Vol. 301, No. 4 ( 2018-04), p. 711-716
    In: The Anatomical Record, Wiley, Vol. 301, No. 4 ( 2018-04), p. 711-716
    Abstract: Recently we reported on the detailed localization of melatonin (and its receptors) in human salivary glands, revealing that serous cells are able to store and secrete melatonin into saliva. Since we found that type 2 diabetic patients display reduced melatonin content in saliva, our next step was to examine the presence of melatonin in salivary glands removed from type 2 diabetic subjects. The resulting data were compared with those previously obtained by identical procedures in non‐diabetics, to establish if the diabetic status may affect melatonin distribution. Bioptic samples of diabetic parotid and submandibular glands were fixed, dehydrated, embedded in Epon Resin and processed to demonstrate melatonin reactivity by the immunogold staining method. The labeling density (expressed as the number of gold particles per μm 2 /granule) and the percentage of melatonin‐positive granules were assessed in diabetic samples. These values were compared with those in non‐diabetic samples and differences were evaluated. In parotid and submandibular diabetic glands the reactivity for melatonin was specifically associated with secretory granules and small vesicles in serous cells. Melatonin reactivity was higher in parotid than in submandibular glands. Our data were in line with those obtained in our previous study on non‐diabetic glands. Diabetic salivary glands showed a higher labeling density and a lower number of melatonin‐positive granules compared to non‐diabetic glands. Taken together, these data might explain the decreased salivary melatonin content and the associated oral problems observed in diabetics. Anat Rec, 301:711–716, 2018. © 2017 Wiley Periodicals, Inc.
    Type of Medium: Online Resource
    ISSN: 1932-8486 , 1932-8494
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2018
    detail.hit.zdb_id: 2273240-8
    detail.hit.zdb_id: 2109216-3
    SSG: 12
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