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Sandra L. Almeyda Zambrano Eben N. Broadbent Sam Shanee Noga Shanee Anneke Deluycker Michael Steinberg Scott A. Ford Alma Hernndez Jaramillo Robin Fernandez‐Hilario Carolina Lagos Castillo Angelica M. Almeyda Zambrano 《American journal of primatology》2019,81(8)
Habitat loss is one of the main threats to wildlife. Therefore, knowledge of habitat use and preference is essential for the design of conservation strategies and identification of priority sites for the protection of endangered species. The yellow‐tailed woolly monkey (Lagothrix flavicauda Humboldt, 1812), categorized as Critically Endangered on the IUCN Red List, is endemic to montane forests in northern Peru where its habitat is greatly threatened. We assessed how habitat use and preference in L. flavicauda are linked to forest structure and composition. The study took place near La Esperanza, in the Amazonas region, Peru. Our objective was to identify characteristics of habitat most utilized by L. flavicauda to provide information that will be useful for the selection of priority sites for conservation measures. Using presence records collected from May 2013 to February 2014 for one group of L. flavicauda, we classified the study site into three different use zones: low‐use, medium‐use, and high‐use. We assessed forest structure and composition for all use zones using 0.1 ha Gentry vegetation transects. Results show high levels of variation in plant species composition across the three use zones. Plants used as food resources had considerably greater density, dominance, and ecological importance in high‐use zones. High‐use zones presented similar structure to medium‐ and low‐use zones; thus it remains difficult to assess the influence of forest structure on habitat preference. We recommend focusing conservation efforts on areas with a similar floristic composition to the high‐use zones recorded in this study and suggest utilizing key alimentation species for reforestation efforts. 相似文献
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Ernesto Rodríguez Verónica Noya Laura Cervi María Laura Chiribao Natalie Brossard Carolina Chiale Carlos Carmona Cecilia Giacomini Teresa Freire 《PLoS neglected tropical diseases》2015,9(12)
Helminths express various carbohydrate-containing glycoconjugates on their surface, and they release glycan-rich excretion/secretion products that can be very important in their life cycles, infection and pathology. Recent evidence suggests that parasite glycoconjugates could play a role in the evasion of the immune response, leading to a modified Th2-polarized immune response that favors parasite survival in the host. Nevertheless, there is limited information about the nature or function of glycans produced by the trematode Fasciola hepatica, the causative agent of fasciolosis. In this paper, we investigate whether glycosylated molecules from F. hepatica participate in the modulation of host immunity. We also focus on dendritic cells, since they are an important target of immune-modulation by helminths, affecting their activity or function. Our results indicate that glycans from F. hepatica promote the production of IL-4 and IL-10, suppressing IFNγ production. During infection, this parasite is able to induce a semi-mature phenotype of DCs expressing low levels of MHCII and secrete IL-10. Furthermore, we show that parasite glycoconjugates mediate the modulation of LPS-induced maturation of DCs since their oxidation restores the capacity of LPS-treated DCs to secrete high levels of the pro-inflammatory cytokines IL-6 and IL-12/23p40 and low levels of the anti-inflammatory cytokine IL-10. Inhibition assays using carbohydrates suggest that the immune-modulation is mediated, at least in part, by the recognition of a mannose specific-CLR that signals by recruiting the phosphatase Php2. The results presented here contribute to the understanding of the role of parasite glycosylated molecules in the modulation of the host immunity and might be useful in the design of vaccines against fasciolosis. 相似文献
5.
AtCOX17 genes encode Arabidopsis thaliana homologs of the yeast metallochaperone Cox17p, involved in the delivery of copper for cytochrome c oxidase (COX) assembly. Two different AtCOX17 genes, located in chromosomes 1 and 3, are present in the Arabidopsis genome. Sequences available in data banks indicate that the presence of two genes is a common feature in monocots, but not in dicots, suggesting that Arabidopsis genes may be the result of a recent duplication. Sequences upstream from the translation start sites of AtCOX17 genes, which include an intron located in the 5' leader region, were introduced into plants in front of the gus gene. For both genes, expression was localized preferentially in young roots and anthers, but almost 10-fold higher β-glucuronidase activity levels were observed in plants transformed with AtCOX17-1 upstream regions. Both promoters were induced to different extents by wounding, treatment of leaves with the bacterial pathogen Pseudomonas syringae and incubation with agents that produce oxidative stress and metals. AtCOX17-2 showed similar responses to these factors, while AtCOX17-1 was more strongly induced by relatively low (10–100 μ M ) copper. The results indicate that both AtCOX17 genes have similar, though not identical, expression characteristics and suggest the existence in their promoters of elements involved in tissue-specific expression and in responses to factors that may produce mitochondrial or cell damage. It can be speculated that Arabidopsis COX17 accumulates under stress conditions to actively replace damaged or inactive cytochrome c oxidase to sustain cyanide-sensitive respiration in plant cells. 相似文献
6.
Anton Pauw Sunshine A. Van Bael Halton A. Peters Steven D. Allison José L. C. Camargo Miguel Cifuentes-Jara Aurlstela Conserva Teresa Garcia Restom Tamara Heartsill-Scalley Scott A. Mangan Gabriela Nunez-lturri Elsie Rivera-Ocasio Mark Rountree Susanne Vetter Carolina Volkmer de Castllho 《Biotropica》2004,36(3):410-413
7.
Monica Rodolfo Carolina Salvi Cinzia Bassi Giorgio Parmiani 《Cancer immunology, immunotherapy : CII》1990,31(1):28-36
Summary We have used a BALB/c colonic adenocarcinoma (C-26) to evaluate the therapeutic potential of recombinant interleukin-2 (rIL-2) at high and low dosages in combination with or without lymphokine-activated killers (LAK) or tumor-specific, immune lymphocytes in either an adjuvant spontaneous or an artificial metastasis system. Most (80%) of the mice that underwent s.c. C-26 tumor excision were shown to die of spontaneous metastasis with lung involvement by 1–4 months after excision. Postsurgical systemic treatment with low-dose rIL-2 (3 × 104 U/day, i.p.) increased the survival rate to 31% as compared to 21% (not significant) in excised controls while administration of high-dose rIL-2 (8 × 104 U/day) led to 53% survival (P <0.01). Both LAK cells and C-26-tumor-immune lymphocytes given during rIL-2 treatment significantly increased the effects of rIL-2 at the low but not at the high-dose, with tumor-immune effectors resulting in the highest percentage (63%) of cures. When mice bearing 3-day artificial lung metastases of C-26 cells were treated with low- or high-dose rIL-2, in combination with or without LAK or tumor-immune lymphocytes, a highly significant reduction or abrogation of the number of lung foci was observed with all treatments, including those involving or tumor-immune lymphocytes alone. Assessment of survival benefit in these mice, however, showed survival prolongation, with 20% cures achieved by low-dose rIL-2 alone and up to 65% cures by LAK in combination with low-dose rIL-2. In this system of artificial metastasis high-dose rIL-2 alone increased the survival time but failed to cure the animals, and the addition of LAK was ineffective whereas that of tumor-immune lymphocytes led to 80% cure. These results suggest that tumorimmune lymphocytes are more effective than LAK when combined with rIL-2 and that caution is necessary in extrapolating findings obtained in artificial metastasis models. 相似文献
8.
Pathology of the human pulmonary paracoccidioidomycosis 总被引:1,自引:1,他引:0
Lungs of twelve patients with chronic paracoccidioidomycosis (Pb) were studied in an attempt to understand the pathogenesis of the pulmonary disease. Ribbons of the lung parenchyma including the hilar region and directed towards apical, basal and lateral regions were subdivided into sections from the hilar, intermediate and peripheral segments. The following histopathological reactions directly or indirectly related to P. brasiliensis were described and analysed in relation to the number of slides studied and the pulmonary region involved: (1) pneumonic reaction; (2) early granulomatous formation; (3) mature and healed granulomata; (4) mixed pattern (early and mature granuloma in the same pulmonary area visualized in the slide); (5) pulmonary fibrosis.It was concluded that chronic pulmonary Pb is a recurrent disease affecting equally both lungs. Fibrosis was connected mainly with the progressive evolution of the granulomata towards cicatrization and to a lesser degree probably to a direct induction by the fungi. Based chiefly on the tendency of the fibrosis to run around bronchi and to make up septa interconnecting bronchi and vessels it was hipothesized that these findings were the result of a previous chronic specific lymphangitis by the fungi. Hilar fibrosis would be the result of this lymphangitis and/or of the progression of the specific granulomatous reaction seen in the hilar lymph nodes.Non specific forms of arteritis and areas of destructive emphysema related to granulomatous inflammation and fibrosis were described. Three cases developed pulmonary hypertension. 相似文献
9.
Polypeptide composition of rat sperm outer dense fibers. A simple procedure to isolate the fibrillar complex 总被引:6,自引:0,他引:6
Treatment of caput or cauda epididymal rat sperm with a low concentration (0.05%) of the cationic detergent cetyltrimethylammonium bromide and 30 mM 2-mercaptoethanol solubilized most of the sperm structures except for the sperm head and the outer dense fiber-connecting piece complex. The latter were purified, and about 10% of these complexes are formed by nine fibers attached to the connecting piece. Of these fibers, two are shorter than the other seven and presumably correspond to fibers 3 and 8 (Fawcett, D.W. (1975) Dev. Biol. 44, 394-436). Electron microscopy confirmed the purity of the isolated outer dense fibers and revealed their characteristic irregular cross-sectional shape. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate showed six major polypeptides (Mr = 87,000, 30,400, 26,000, 18,400, 13,000, and 11,500) with a high content of serine, aspartic and glutamic acids, proline, cysteine, leucine, and tyrosine. Furthermore, several lines of evidence indicate a close structural relationship between the components of 30,400 and 26,000 Da. The six major components of the fibers are phosphorylated at serine residues. These results indicate that the major components of rat sperm outer dense fibers are a unique family of phosphoproteins. 相似文献
10.